Release v0.29.3

This fixes an issue where if you try to write to the same destination as the
input file but you are not using absolute (or the same relative path) for both
the input and output, sharp/vips might produce errors such as:

someFile.jpg: unable to open for write
unix error: No such file or directory

.circleci/config.yml

@@ -0,0 +1,77 @@
+version: 2.1
+
+workflows:
+  build:
+    jobs:
+      - linux-arm64-glibc-node-12:
+          filters:
+            tags:
+              only: /^v.*/
+      - linux-arm64-musl-node-12:
+          filters:
+            tags:
+              only: /^v.*/
+      - linux-arm64-glibc-node-16:
+          filters:
+            tags:
+              only: /^v.*/
+      - linux-arm64-musl-node-16:
+          filters:
+            tags:
+              only: /^v.*/
+
+jobs:
+  linux-arm64-glibc-node-12:
+    resource_class: arm.medium
+    machine:
+      image: ubuntu-2004:202101-01
+    steps:
+      - checkout
+      - run: |
+          sudo docker run -dit --name sharp --volume "${PWD}:/mnt/sharp" --workdir /mnt/sharp arm64v8/debian:bullseye
+          sudo docker exec sharp sh -c "apt-get update && apt-get install -y build-essential git python3 curl"
+          sudo docker exec sharp sh -c "curl -s https://deb.nodesource.com/gpgkey/nodesource.gpg.key | apt-key add -"
+          sudo docker exec sharp sh -c "echo 'deb https://deb.nodesource.com/node_12.x sid main' >/etc/apt/sources.list.d/nodesource.list"
+          sudo docker exec sharp sh -c "apt-get update && apt-get install -y nodejs"
+      - run: sudo docker exec sharp sh -c "npm install --build-from-source --unsafe-perm"
+      - run: sudo docker exec sharp sh -c "npm test"
+      - run: "[[ -n $CIRCLE_TAG ]] && sudo docker exec --env prebuild_upload sharp sh -c \"npx prebuild --runtime napi --target 5 --upload=$prebuild_upload\" || true"
+  linux-arm64-glibc-node-16:
+    resource_class: arm.medium
+    machine:
+      image: ubuntu-2004:202101-01
+    steps:
+      - checkout
+      - run: |
+          sudo chown 0.0 ${PWD}
+          sudo docker run -dit --name sharp --volume "${PWD}:/mnt/sharp" --workdir /mnt/sharp arm64v8/debian:bullseye
+          sudo docker exec sharp sh -c "apt-get update && apt-get install -y build-essential git python3 curl"
+          sudo docker exec sharp sh -c "curl -s https://deb.nodesource.com/gpgkey/nodesource.gpg.key | apt-key add -"
+          sudo docker exec sharp sh -c "echo 'deb https://deb.nodesource.com/node_16.x sid main' >/etc/apt/sources.list.d/nodesource.list"
+          sudo docker exec sharp sh -c "apt-get update && apt-get install -y nodejs"
+      - run: sudo docker exec sharp sh -c "npm install --build-from-source --unsafe-perm"
+      - run: sudo docker exec sharp sh -c "npm test"
+  linux-arm64-musl-node-12:
+    resource_class: arm.medium
+    machine:
+      image: ubuntu-2004:202101-01
+    steps:
+      - checkout
+      - run: |
+          sudo docker run -dit --name sharp --volume "${PWD}:/mnt/sharp" --workdir /mnt/sharp node:12-alpine3.11
+          sudo docker exec sharp sh -c "apk add build-base git python3 --update-cache"
+      - run: sudo docker exec sharp sh -c "npm install --build-from-source --unsafe-perm"
+      - run: sudo docker exec sharp sh -c "npm test"
+      - run: "[[ -n $CIRCLE_TAG ]] && sudo docker exec --env prebuild_upload sharp sh -c \"npx prebuild --runtime napi --target 5 --upload=$prebuild_upload\" || true"
+  linux-arm64-musl-node-16:
+    resource_class: arm.medium
+    machine:
+      image: ubuntu-2004:202101-01
+    steps:
+      - checkout
+      - run: |
+          sudo chown 0.0 ${PWD}
+          sudo docker run -dit --name sharp --volume "${PWD}:/mnt/sharp" --workdir /mnt/sharp node:16-alpine3.11
+          sudo docker exec sharp sh -c "apk add build-base git python3 --update-cache"
+      - run: sudo docker exec sharp sh -c "npm install --build-from-source --unsafe-perm"
+      - run: sudo docker exec sharp sh -c "npm test"

.cirrus.yml

@@ -0,0 +1,16 @@
+freebsd_instance:
+  image_family: freebsd-13-0-snap
+
+task:
+  name: FreeBSD 13.0
+  env:
+    IGNORE_OSVERSION: yes
+  skip_notifications: true
+  prerequisites_script:
+    - pkg update -f
+    - pkg upgrade -y
+    - pkg install -y pkgconf vips node npm
+  install_script:
+    - npm install --build-from-source --unsafe-perm
+  test_script:
+    - npm test

.github/CONTRIBUTING.md

@@ -12,9 +12,12 @@ New bugs are assigned a `triage` label whilst under investigation.
 
 ## Submit a new feature request
 
-If a [similar request](https://github.com/lovell/sharp/labels/enhancement) exists, it's probably fastest to add a comment to it about your requirement.
+If a [similar request](https://github.com/lovell/sharp/labels/enhancement) exists,
+it's probably fastest to add a comment to it about your requirement.
 
-Implementation is usually straightforward if _libvips_ [already supports](https://jcupitt.github.io/libvips/API/current/) the feature you need.
+Implementation is usually straightforward if libvips
+[already supports](https://libvips.github.io/libvips/API/current/func-list.html)
+the feature you need.
 
 ## Submit a Pull Request to fix a bug
 
@@ -24,7 +27,7 @@ Please select the `master` branch as the destination for your Pull Request so yo
 
 Please squash your changes into a single commit using a command like `git rebase -i upstream/master`.
 
-To test C++ changes, you can compile the module using `npm install` and then run the tests using `npm test`.
+To test C++ changes, you can compile the module using `npm install --build-from-source` and then run the tests using `npm test`.
 
 ## Submit a Pull Request with a new feature
 
@@ -39,21 +42,15 @@ You deserve to add your details to the [list of contributors](https://github.com
 
 Any change that modifies the existing public API should be added to the relevant work-in-progress branch for inclusion in the next major release.
 
-| Release | WIP branch |
-| ------: | :--------- |
-| v0.20.0 | prebuild   |
-| v0.21.0 | teeth      |
-| v0.22.0 | uptake     |
-
 Please squash your changes into a single commit using a command like `git rebase -i upstream/<wip-branch>`.
 
 ### Add a new public method
 
-The API tries to be as fluent as possible. Image processing concepts follow the naming conventions from _libvips_ and, to a lesser extent, _ImageMagick_.
+The API tries to be as fluent as possible.
+Image processing concepts follow the naming conventions from libvips and, to a lesser extent, ImageMagick.
 
-Most methods have optional parameters and assume sensible defaults. Methods with mandatory parameters often have names like `doSomethingWith(X)`.
-
-Please ensure backwards compatibility where possible. Methods to modify previously default behaviour often have names like `withoutOptionY()` or `withExtraZ()`.
+Most methods have optional parameters and assume sensible defaults.
+Please ensure backwards compatibility where possible.
 
 Feel free to create a [new issue](https://github.com/lovell/sharp/issues/new) to gather feedback on a potential API change.
 
@@ -61,7 +58,7 @@ Feel free to create a [new issue](https://github.com/lovell/sharp/issues/new) to
 
 A method to be removed should be deprecated in the next major version then removed in the following major version.
 
-By way of example, the [bilinearInterpolation method](https://github.com/lovell/sharp/blob/v0.6.0/index.js#L155) present in v0.5.0 was deprecated in v0.6.0 and removed in v0.7.0.
+By way of example, the `background()` method present in v0.20.0 was deprecated in v0.21.0 and removed in v0.22.0.
 
 ## Documentation
 
@@ -69,7 +66,7 @@ The public API is documented with [JSDoc](http://usejsdoc.org/) annotated commen
 
 These can be converted to Markdown by running:
 ```sh
-npm run docs
+npm run docs-build
 ```
 
 Please include documentation updates in any Pull Request that modifies the public API.
@@ -90,20 +87,11 @@ Requires [Valgrind](http://valgrind.org/).
 npm run test-leak
 ```
 
-### Packaging tests
-
-Tests the installation on a number of Linux-based operating systems.
-Requires docker.
-
-```sh
-npm run test-packaging
-```
-
 ## Finally
 
 Please feel free to ask any questions via a
 [new issue](https://github.com/lovell/sharp/issues/new).
 
 If you're unable to post details publicly, please
-[e-mail](https://github.com/lovell/sharp/blob/master/package.json#L4)
+[e-mail](https://github.com/lovell/sharp/blob/master/package.json#L5)
 for private, paid consulting.

.github/FUNDING.yml

@@ -0,0 +1 @@
+open_collective: libvips

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Documentation
+    url: https://sharp.pixelplumbing.com/
+    about: Installation instructions, complete API documentation with examples, changelog

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,16 @@
+---
+name: Feature request
+about: Suggest an idea
+labels: enhancement
+
+---
+
+What are you trying to achieve?
+
+Have you searched for similar feature requests?
+
+What would you expect the API to look like?
+
+What alternatives have you considered?
+
+Is there a sample image that helps explain?

.github/ISSUE_TEMPLATE/installation.md

@@ -0,0 +1,22 @@
+---
+name: Installation
+about: Something went wrong during either 'npm install sharp' or 'require("sharp")'
+labels: installation
+
+---
+
+Did you see the [documentation relating to installation](https://sharp.pixelplumbing.com/install)?
+
+Have you ensured the architecture and platform of Node.js used for `npm install` is the same as the architecture and platform of Node.js used at runtime?
+
+Are you using the latest version? Is the version currently in use as reported by `npm ls sharp` the same as the latest version as reported by `npm view sharp dist-tags.latest`?
+
+If you are using npm v6 or earlier and installing as a `root` or `sudo` user, have you tried with the `npm install --unsafe-perm` flag?
+
+If you are using npm v7, does the user running `npm install` own the directory it is run in?
+
+If you are using the `ignore-scripts` feature of `npm`, have you tried with the `npm install --ignore-scripts=false` flag?
+
+What is the complete output of running `npm install --verbose sharp`? Have you checked this output for useful error messages?
+
+What is the output of running `npx envinfo --binaries --system`?

.github/ISSUE_TEMPLATE/possible-bug.md

@@ -0,0 +1,20 @@
+---
+name: Possible bug
+about: Installation of sharp was successful but then something unexpected occurred using one of its features
+labels: triage
+
+---
+
+<!-- If this issue relates to installation, please use https://github.com/lovell/sharp/issues/new?labels=installation&template=installation.md instead. -->
+
+Are you using the latest version? Is the version currently in use as reported by `npm ls sharp` the same as the latest version as reported by `npm view sharp dist-tags.latest`?
+
+What are the steps to reproduce?
+
+What is the expected behaviour?
+
+Are you able to provide a minimal, standalone code sample, without other dependencies, that demonstrates this problem?
+
+Are you able to provide a sample image that helps explain the problem?
+
+What is the output of running `npx envinfo --binaries --system`?

.github/ISSUE_TEMPLATE/question.md

@@ -0,0 +1,16 @@
+---
+name: Question
+about: For help understanding an existing feature
+labels: question
+
+---
+
+<!-- If this issue relates to installation, please use https://github.com/lovell/sharp/issues/new?labels=installation&template=installation.md instead. -->
+
+What are you trying to achieve?
+
+Have you searched for similar questions?
+
+Are you able to provide a minimal, standalone code sample that demonstrates this question?
+
+Are you able to provide a sample image that helps explain the question?

.github/workflows/ci-darwin-arm64v8.yml

@@ -0,0 +1,27 @@
+name: CI (MacStadium)
+on:
+  - push
+  - pull_request
+jobs:
+  CI:
+    runs-on: macos-m1
+    defaults:
+      run:
+        shell: /usr/bin/arch -arch arm64e /bin/bash -l {0}
+    steps:
+      - name: Dependencies
+        uses: actions/setup-node@v2
+        with:
+          node-version: 16
+          architecture: arm64
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Install
+        run: npm install --build-from-source --unsafe-perm
+      - name: Test
+        run: npm test
+      - name: Prebuild
+        if: startsWith(github.ref, 'refs/tags/')
+        env:
+          prebuild_upload: ${{ secrets.GITHUB_TOKEN }}
+        run: npx prebuild --runtime napi --target 5

.github/workflows/ci.yml

@@ -0,0 +1,81 @@
+name: CI (GitHub)
+on:
+  - push
+  - pull_request
+jobs:
+  CI:
+    runs-on: ${{ matrix.os }}
+    container: ${{ matrix.container }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: ubuntu-20.04
+            container: centos:7
+            nodejs_version: 12
+            coverage: true
+            prebuild: true
+          - os: ubuntu-20.04
+            container: centos:7
+            nodejs_version: 14
+          - os: ubuntu-20.04
+            container: centos:7
+            nodejs_version: 16
+          - os: ubuntu-20.04
+            container: node:12-alpine3.11
+            prebuild: true
+          - os: ubuntu-20.04
+            container: node:14-alpine3.11
+          - os: ubuntu-20.04
+            container: node:14-alpine3.13
+          - os: ubuntu-20.04
+            container: node:16-alpine3.11
+          - os: macos-10.15
+            nodejs_version: 12
+            prebuild: true
+          - os: macos-10.15
+            nodejs_version: 14
+          - os: macos-10.15
+            nodejs_version: 16
+          - os: windows-2019
+            nodejs_version: 12
+            prebuild: true
+          - os: windows-2019
+            nodejs_version: 14
+          - os: windows-2019
+            nodejs_version: 16
+    steps:
+      - name: Dependencies (Linux glibc)
+        if: contains(matrix.container, 'centos')
+        run: |
+          curl -sL https://rpm.nodesource.com/setup_${{ matrix.nodejs_version }}.x | bash -
+          yum install -y centos-release-scl
+          yum install -y devtoolset-10-gcc-c++ make git python3 nodejs
+          echo "/opt/rh/devtoolset-10/root/usr/bin" >> $GITHUB_PATH
+      - name: Dependencies (Linux musl)
+        if: contains(matrix.container, 'alpine')
+        run: apk add build-base git python3 --update-cache
+      - name: Dependencies (macOS, Windows)
+        if: contains(matrix.os, 'macos') || contains(matrix.os, 'windows')
+        uses: actions/setup-node@v1
+        with:
+          node-version: ${{ matrix.nodejs_version }}
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Fix working directory ownership
+        if: matrix.container
+        run: chown root.root .
+      - name: Install
+        run: npm install --build-from-source --unsafe-perm
+      - name: Test
+        run: npm test
+      - name: Coverage
+        if: matrix.coverage
+        uses: coverallsapp/github-action@v1.1.2
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+      - name: Prebuild
+        if: matrix.prebuild && startsWith(github.ref, 'refs/tags/')
+        env:
+          prebuild_upload: ${{ secrets.GITHUB_TOKEN }}
+        run: npx prebuild --runtime napi --target 5

.gitignore

@@ -12,3 +12,7 @@ vendor
 .gitattributes
 .DS_Store
 .nyc_output
+.vscode/
+package-lock.json
+.idea
+.firebase

.npmignore

@@ -1,13 +0,0 @@
-build
-node_modules
-coverage
-.editorconfig
-.gitattributes
-.gitignore
-test
-.travis.yml
-appveyor.yml
-mkdocs.yml
-vendor
-.nyc_output
-CONTRIBUTING.md

.prebuildrc

@@ -0,0 +1,4 @@
+{
+  "include-regex": "(sharp-.+\\.node|libvips-cpp\\.dll)",
+  "strip": true
+}

.travis.yml

@@ -1,34 +0,0 @@
-language: node_js
-matrix:
-  include:
-    - os: linux
-      dist: trusty
-      sudo: false
-      node_js: "4"
-    - os: linux
-      dist: trusty
-      sudo: false
-      node_js: "6"
-    - os: linux
-      dist: trusty
-      sudo: false
-      node_js: "8"
-    - os: linux
-      dist: trusty
-      sudo: false
-      node_js: "9"
-    - os: osx
-      osx_image: xcode8.3
-      node_js: "4"
-    - os: osx
-      osx_image: xcode8.3
-      node_js: "6"
-    - os: osx
-      osx_image: xcode8.3
-      node_js: "8"
-    - os: osx
-      osx_image: xcode8.3
-      node_js: "9"
-after_success:
-  - npm install coveralls
-  - cat ./coverage/lcov.info | ./node_modules/coveralls/bin/coveralls.js

README.md

@@ -1,15 +1,14 @@
 # sharp
 
-```sh
-npm install sharp
-```
+<img src="https://cdn.jsdelivr.net/gh/lovell/sharp@master/docs/image/sharp-logo.svg" width="160" height="160" alt="sharp logo" align="right">
 
 The typical use case for this high speed Node.js module
 is to convert large images in common formats to
-smaller, web-friendly JPEG, PNG and WebP images of varying dimensions.
+smaller, web-friendly JPEG, PNG, WebP and AVIF images of varying dimensions.
 
 Resizing an image is typically 4x-5x faster than using the
-quickest ImageMagick and GraphicsMagick settings.
+quickest ImageMagick and GraphicsMagick settings
+due to its use of [libvips](https://github.com/libvips/libvips).
 
 Colour spaces, embedded ICC profiles and alpha transparency channels are all handled correctly.
 Lanczos resampling ensures quality is not sacrificed for speed.
@@ -17,40 +16,76 @@ Lanczos resampling ensures quality is not sacrificed for speed.
 As well as image resizing, operations such as
 rotation, extraction, compositing and gamma correction are available.
 
-OS X, Windows (x64), Linux (x64, ARM) systems do not require
-the installation of any external runtime dependencies.
+Most modern macOS, Windows and Linux systems running Node.js >= 12.13.0
+do not require any additional install or runtime dependencies.
+
+## Documentation
+
+Visit [sharp.pixelplumbing.com](https://sharp.pixelplumbing.com/) for complete
+[installation instructions](https://sharp.pixelplumbing.com/install),
+[API documentation](https://sharp.pixelplumbing.com/api-constructor),
+[benchmark tests](https://sharp.pixelplumbing.com/performance) and
+[changelog](https://sharp.pixelplumbing.com/changelog).
 
 ## Examples
 
+```sh
+npm install sharp
+```
+
 ```javascript
 const sharp = require('sharp');
 ```
 
+### Callback
+
 ```javascript
 sharp(inputBuffer)
   .resize(320, 240)
-  .toFile('output.webp', (err, info) => ... );
-  // A Promises/A+ promise is returned when callback is not provided.
+  .toFile('output.webp', (err, info) => { ... });
 ```
 
+### Promise
+
 ```javascript
 sharp('input.jpg')
   .rotate()
   .resize(200)
+  .jpeg({ mozjpeg: true })
   .toBuffer()
-  .then( data => ... )
-  .catch( err => ... );
+  .then( data => { ... })
+  .catch( err => { ... });
 ```
 
+### Async/await
+
 ```javascript
-const roundedCorners = new Buffer(
+const semiTransparentRedPng = await sharp({
+  create: {
+    width: 48,
+    height: 48,
+    channels: 4,
+    background: { r: 255, g: 0, b: 0, alpha: 0.5 }
+  }
+})
+  .png()
+  .toBuffer();
+```
+
+### Stream
+
+```javascript
+const roundedCorners = Buffer.from(
   '<svg><rect x="0" y="0" width="200" height="200" rx="50" ry="50"/></svg>'
 );
 
 const roundedCornerResizer =
   sharp()
     .resize(200, 200)
-    .overlayWith(roundedCorners, { cutout: true })
+    .composite([{
+      input: roundedCorners,
+      blend: 'dest-in'
+    }])
     .png();
 
 readableStream
@@ -58,29 +93,22 @@ readableStream
   .pipe(writableStream);
 ```
 
-[![Test Coverage](https://coveralls.io/repos/lovell/sharp/badge.png?branch=master)](https://coveralls.io/r/lovell/sharp?branch=master)
+## Contributing
 
-### Documentation
-
-Visit [sharp.pixelplumbing.com](http://sharp.pixelplumbing.com/) for complete
-[installation instructions](http://sharp.pixelplumbing.com/page/install),
-[API documentation](http://sharp.pixelplumbing.com/page/api),
-[benchmark tests](http://sharp.pixelplumbing.com/page/performance) and
-[changelog](http://sharp.pixelplumbing.com/page/changelog).
-
-### Contributing
-
-A [guide for contributors](https://github.com/lovell/sharp/blob/master/CONTRIBUTING.md)
+A [guide for contributors](https://github.com/lovell/sharp/blob/master/.github/CONTRIBUTING.md)
 covers reporting bugs, requesting features and submitting code changes.
 
-### Licence
+[![Test Coverage](https://coveralls.io/repos/lovell/sharp/badge.svg?branch=master)](https://coveralls.io/r/lovell/sharp?branch=master)
+[![Node-API v5](https://img.shields.io/badge/Node--API-v5-green.svg)](https://nodejs.org/dist/latest/docs/api/n-api.html#n_api_n_api_version_matrix)
 
-Copyright 2013, 2014, 2015, 2016, 2017, 2018 Lovell Fuller and contributors.
+## Licensing
+
+Copyright 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021 Lovell Fuller and contributors.
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at
-[http://www.apache.org/licenses/LICENSE-2.0](http://www.apache.org/licenses/LICENSE-2.0.html)
+[https://www.apache.org/licenses/LICENSE-2.0](https://www.apache.org/licenses/LICENSE-2.0)
 
 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,

appveyor.yml

@@ -1,16 +1,17 @@
-os: Visual Studio 2015
+os: Visual Studio 2019
 version: "{build}"
 build: off
-platform: x64
+platform: x86
 environment:
   matrix:
-  - nodejs_version: "4"
-  - nodejs_version: "6"
-  - nodejs_version: "8"
-  - nodejs_version: "9"
+  - nodejs_version: "12"
+    prebuild: true
+  - nodejs_version: "14"
+  - nodejs_version: "16"
 install:
-  - ps: Install-Product node $env:nodejs_version x64
-  - npm install -g npm@5.3.x
-  - npm install
+  - ps: Update-NodeJsInstallation (Get-NodeJsLatestBuild $env:nodejs_version)
+  - npm install --build-from-source
 test_script:
   - npm test
+on_success:
+  - if [%prebuild%] == [true] if [%APPVEYOR_REPO_TAG%] == [true] npx prebuild --runtime napi --target 5

binding.gyp

@@ -1,37 +1,59 @@
 {
+  'variables': {
+    'vips_version': '<!(node -p "require(\'./lib/libvips\').minimumLibvipsVersion")',
+    'platform_and_arch': '<!(node -p "require(\'./lib/platform\')()")',
+    'sharp_vendor_dir': './vendor/<(vips_version)/<(platform_and_arch)'
+  },
   'targets': [{
     'target_name': 'libvips-cpp',
     'conditions': [
       ['OS == "win"', {
         # Build libvips C++ binding for Windows due to MSVC std library ABI changes
         'type': 'shared_library',
-        'variables': {
-          'download_vips': '<!(node -e "require(\'./binding\').download_vips()")'
-        },
         'defines': [
           'VIPS_CPLUSPLUS_EXPORTS',
           '_ALLOW_KEYWORD_MACROS'
         ],
         'sources': [
           'src/libvips/cplusplus/VError.cpp',
+          'src/libvips/cplusplus/VConnection.cpp',
           'src/libvips/cplusplus/VInterpolate.cpp',
           'src/libvips/cplusplus/VImage.cpp'
         ],
         'include_dirs': [
-          'vendor/include',
-          'vendor/include/glib-2.0',
-          'vendor/lib/glib-2.0/include'
-        ],
-        'libraries': [
-          '../vendor/lib/libvips.lib',
-          '../vendor/lib/libglib-2.0.lib',
-          '../vendor/lib/libgobject-2.0.lib'
+          '<(sharp_vendor_dir)/include',
+          '<(sharp_vendor_dir)/include/glib-2.0',
+          '<(sharp_vendor_dir)/lib/glib-2.0/include'
         ],
+        'link_settings': {
+          'library_dirs': ['<(sharp_vendor_dir)/lib'],
+          'libraries': [
+            'libvips.lib',
+            'libglib-2.0.lib',
+            'libgobject-2.0.lib'
+          ],
+        },
         'configurations': {
           'Release': {
             'msvs_settings': {
               'VCCLCompilerTool': {
-                'ExceptionHandling': 1
+                'ExceptionHandling': 1,
+                'Optimization': 1,
+                'WholeProgramOptimization': 'true'
+              },
+              'VCLibrarianTool': {
+                'AdditionalOptions': [
+                  '/LTCG:INCREMENTAL'
+                ]
+              },
+              'VCLinkerTool': {
+                'ImageHasSafeExceptionHandlers': 'false',
+                'OptimizeReferences': 2,
+                'EnableCOMDATFolding': 2,
+                'LinkIncremental': 1,
+                'AdditionalOptions': [
+                  '/LTCG:INCREMENTAL'
+                ]
               }
             },
             'msvs_disabled_warnings': [
@@ -45,41 +67,23 @@
       }]
     ]
   }, {
-    'target_name': 'sharp',
+    'target_name': 'sharp-<(platform_and_arch)',
+    'defines': [
+      'NAPI_VERSION=5'
+    ],
     'dependencies': [
+      '<!(node -p "require(\'node-addon-api\').gyp")',
       'libvips-cpp'
     ],
-    # Nested variables "pattern" borrowed from http://src.chromium.org/viewvc/chrome/trunk/src/build/common.gypi
     'variables': {
-      'variables': {
-        'variables': {
-          'conditions': [
-            ['OS != "win"', {
-              # Build the PKG_CONFIG_PATH environment variable with all possible combinations
-              'pkg_config_path': '<!(which brew >/dev/null 2>&1 && eval $(brew --env) && echo $PKG_CONFIG_LIBDIR || true):$PKG_CONFIG_PATH:/usr/local/lib/pkgconfig:/usr/lib/pkgconfig'
-            }, {
-              'pkg_config_path': ''
-            }]
-          ],
-        },
-        'conditions': [
-          ['OS != "win"', {
-            # Which version, if any, of libvips is available globally via pkg-config?
-            'global_vips_version': '<!(PKG_CONFIG_PATH="<(pkg_config_path)" pkg-config --modversion vips-cpp 2>/dev/null || true)'
-          }, {
-            'global_vips_version': ''
-          }]
-        ],
-        'pkg_config_path%': '<(pkg_config_path)'
-      },
-      'pkg_config_path%': '<(pkg_config_path)',
       'runtime_link%': 'shared',
       'conditions': [
         ['OS != "win"', {
-          # Does the globally available version of libvips, if any, meet the minimum version requirement?
-          'use_global_vips': '<!(GLOBAL_VIPS_VERSION="<(global_vips_version)" node -e "require(\'./binding\').use_global_vips()")'
+          'pkg_config_path': '<!(node -p "require(\'./lib/libvips\').pkgConfigPath()")',
+          'use_global_libvips': '<!(node -p "Boolean(require(\'./lib/libvips\').useGlobalLibvips()).toString()")'
         }, {
-          'use_global_vips': ''
+          'pkg_config_path': '',
+          'use_global_libvips': ''
         }]
       ]
     },
@@ -89,14 +93,14 @@
       'src/stats.cc',
       'src/operations.cc',
       'src/pipeline.cc',
-      'src/sharp.cc',
-      'src/utilities.cc'
+      'src/utilities.cc',
+      'src/sharp.cc'
     ],
     'include_dirs': [
-      '<!(node -e "require(\'nan\')")'
+      '<!(node -p "require(\'node-addon-api\').include_dir")',
     ],
     'conditions': [
-      ['use_global_vips == "true"', {
+      ['use_global_libvips == "true"', {
         # Use pkg-config for include and lib
         'include_dirs': ['<!@(PKG_CONFIG_PATH="<(pkg_config_path)" pkg-config --cflags-only-I vips-cpp vips glib-2.0 | sed s\/-I//g)'],
         'conditions': [
@@ -113,78 +117,55 @@
           }]
         ]
       }, {
-        # Attempt to download pre-built libvips and install locally within node_modules
+        # Use pre-built libvips stored locally within node_modules
         'include_dirs': [
-          'vendor/include',
-          'vendor/include/glib-2.0',
-          'vendor/lib/glib-2.0/include'
+          '<(sharp_vendor_dir)/include',
+          '<(sharp_vendor_dir)/include/glib-2.0',
+          '<(sharp_vendor_dir)/lib/glib-2.0/include'
         ],
         'conditions': [
           ['OS == "win"', {
             'defines': [
-              '_ALLOW_KEYWORD_MACROS'
+              '_ALLOW_KEYWORD_MACROS',
+              '_FILE_OFFSET_BITS=64'
             ],
-            'libraries': [
-              '../vendor/lib/libvips.lib',
-              '../vendor/lib/libglib-2.0.lib',
-              '../vendor/lib/libgobject-2.0.lib'
-            ]
+            'link_settings': {
+              'library_dirs': ['<(sharp_vendor_dir)/lib'],
+              'libraries': [
+                'libvips.lib',
+                'libglib-2.0.lib',
+                'libgobject-2.0.lib'
+              ]
+            }
           }],
           ['OS == "mac"', {
-            'variables': {
-              'download_vips': '<!(node -e "require(\'./binding\').download_vips()")'
+            'link_settings': {
+              'library_dirs': ['../<(sharp_vendor_dir)/lib'],
+              'libraries': [
+                'libvips-cpp.42.dylib'
+              ]
             },
-            'libraries': [
-              '../vendor/lib/libvips-cpp.42.dylib',
-              '../vendor/lib/libvips.42.dylib',
-              '../vendor/lib/libglib-2.0.0.dylib',
-              '../vendor/lib/libgobject-2.0.0.dylib',
-              # Ensure runtime linking is relative to sharp.node
-              '-rpath \'@loader_path/../../vendor/lib\''
-            ]
+            'xcode_settings': {
+              'OTHER_LDFLAGS': [
+                # Ensure runtime linking is relative to sharp.node
+                '-Wl,-rpath,\'@loader_path/../../<(sharp_vendor_dir)/lib\''
+              ]
+            }
           }],
           ['OS == "linux"', {
-            'variables': {
-              'download_vips': '<!(node -e "require(\'./binding\').download_vips()")'
-            },
             'defines': [
-              '_GLIBCXX_USE_CXX11_ABI=0'
+              '_GLIBCXX_USE_CXX11_ABI=1'
             ],
-            'libraries': [
-              '../vendor/lib/libvips-cpp.so',
-              '../vendor/lib/libvips.so',
-              '../vendor/lib/libglib-2.0.so',
-              '../vendor/lib/libgobject-2.0.so',
-              # Dependencies of dependencies, included for openSUSE support
-              '../vendor/lib/libcairo.so',
-              '../vendor/lib/libcroco-0.6.so',
-              '../vendor/lib/libexif.so',
-              '../vendor/lib/libffi.so',
-              '../vendor/lib/libfontconfig.so',
-              '../vendor/lib/libfreetype.so',
-              '../vendor/lib/libgdk_pixbuf-2.0.so',
-              '../vendor/lib/libgif.so',
-              '../vendor/lib/libgio-2.0.so',
-              '../vendor/lib/libgmodule-2.0.so',
-              '../vendor/lib/libgsf-1.so',
-              '../vendor/lib/libgthread-2.0.so',
-              '../vendor/lib/libharfbuzz.so',
-              '../vendor/lib/libjpeg.so',
-              '../vendor/lib/liblcms2.so',
-              '../vendor/lib/liborc-0.4.so',
-              '../vendor/lib/libpango-1.0.so',
-              '../vendor/lib/libpangocairo-1.0.so',
-              '../vendor/lib/libpangoft2-1.0.so',
-              '../vendor/lib/libpixman-1.so',
-              '../vendor/lib/libpng.so',
-              '../vendor/lib/librsvg-2.so',
-              '../vendor/lib/libtiff.so',
-              '../vendor/lib/libwebp.so',
-              '../vendor/lib/libxml2.so',
-              '../vendor/lib/libz.so',
-              # Ensure runtime linking is relative to sharp.node
-              '-Wl,--disable-new-dtags -Wl,-rpath=\'$${ORIGIN}/../../vendor/lib\''
-            ]
+            'link_settings': {
+              'library_dirs': ['../<(sharp_vendor_dir)/lib'],
+              'libraries': [
+                '-l:libvips-cpp.so.42'
+              ],
+              'ldflags': [
+                # Ensure runtime linking is relative to sharp.node
+                '-Wl,-s -Wl,--disable-new-dtags -Wl,-rpath=\'$$ORIGIN/../../<(sharp_vendor_dir)/lib\''
+              ]
+            }
           }]
         ]
       }]
@@ -193,91 +174,60 @@
       '-std=c++0x',
       '-fexceptions',
       '-Wall',
-      '-O3'
+      '-Os'
     ],
     'xcode_settings': {
       'CLANG_CXX_LANGUAGE_STANDARD': 'c++11',
-      'CLANG_CXX_LIBRARY': 'libc++',
-      'MACOSX_DEPLOYMENT_TARGET': '10.7',
+      'MACOSX_DEPLOYMENT_TARGET': '10.9',
       'GCC_ENABLE_CPP_EXCEPTIONS': 'YES',
       'GCC_ENABLE_CPP_RTTI': 'YES',
       'OTHER_CPLUSPLUSFLAGS': [
         '-fexceptions',
         '-Wall',
-        '-O3'
+        '-Oz'
       ]
     },
     'configurations': {
       'Release': {
-        'msvs_settings': {
-          'VCCLCompilerTool': {
-            'ExceptionHandling': 1
-          }
-        },
-        'msvs_disabled_warnings': [
-          4275
+        'conditions': [
+          ['OS == "linux"', {
+            'cflags_cc': [
+              '-Wno-cast-function-type'
+            ]
+          }],
+          ['target_arch == "arm"', {
+            'cflags_cc': [
+              '-Wno-psabi'
+            ]
+          }],
+          ['OS == "win"', {
+            'msvs_settings': {
+              'VCCLCompilerTool': {
+                'ExceptionHandling': 1,
+                'Optimization': 1,
+                'WholeProgramOptimization': 'true'
+              },
+              'VCLibrarianTool': {
+                'AdditionalOptions': [
+                  '/LTCG:INCREMENTAL'
+                ]
+              },
+              'VCLinkerTool': {
+                'ImageHasSafeExceptionHandlers': 'false',
+                'OptimizeReferences': 2,
+                'EnableCOMDATFolding': 2,
+                'LinkIncremental': 1,
+                'AdditionalOptions': [
+                  '/LTCG:INCREMENTAL'
+                ]
+              }
+            },
+            'msvs_disabled_warnings': [
+              4275
+            ]
+          }]
         ]
       }
     },
-  }, {
-    'target_name': 'win_copy_dlls',
-    'type': 'none',
-    'dependencies': [
-      'sharp'
-    ],
-    'conditions': [
-      ['OS == "win"', {
-        # Windows lacks support for rpath
-        'copies': [{
-          'destination': 'build/Release',
-          'files': [
-            'vendor/lib/libasprintf-0.dll',
-            'vendor/lib/libcairo-2.dll',
-            'vendor/lib/libcairo-gobject-2.dll',
-            'vendor/lib/libcairo-script-interpreter-2.dll',
-            'vendor/lib/libcharset-1.dll',
-            'vendor/lib/libcroco-0.6-3.dll',
-            'vendor/lib/libexif-12.dll',
-            'vendor/lib/libexpat-1.dll',
-            'vendor/lib/libffi-6.dll',
-            'vendor/lib/libfftw3-3.dll',
-            'vendor/lib/libfontconfig-1.dll',
-            'vendor/lib/libfreetype-6.dll',
-            'vendor/lib/libgcc_s_seh-1.dll',
-            'vendor/lib/libgdk_pixbuf-2.0-0.dll',
-            'vendor/lib/libgettextlib-0-19-8.dll',
-            'vendor/lib/libgettextpo-1.dll',
-            'vendor/lib/libgettextsrc-0-19-8.dll',
-            'vendor/lib/libgif-7.dll',
-            'vendor/lib/libgio-2.0-0.dll',
-            'vendor/lib/libglib-2.0-0.dll',
-            'vendor/lib/libgmodule-2.0-0.dll',
-            'vendor/lib/libgobject-2.0-0.dll',
-            'vendor/lib/libgsf-1-114.dll',
-            'vendor/lib/libgthread-2.0-0.dll',
-            'vendor/lib/libharfbuzz-0.dll',
-            'vendor/lib/libiconv-2.dll',
-            'vendor/lib/libintl-9.dll',
-            'vendor/lib/libjpeg-62.dll',
-            'vendor/lib/liblcms2-2.dll',
-            'vendor/lib/libpango-1.0-0.dll',
-            'vendor/lib/libpangocairo-1.0-0.dll',
-            'vendor/lib/libpangoft2-1.0-0.dll',
-            'vendor/lib/libpangowin32-1.0-0.dll',
-            'vendor/lib/libpixman-1-0.dll',
-            'vendor/lib/libpng16-16.dll',
-            'vendor/lib/libquadmath-0.dll',
-            'vendor/lib/librsvg-2-2.dll',
-            'vendor/lib/libssp-0.dll',
-            'vendor/lib/libstdc++-6.dll',
-            'vendor/lib/libtiff-5.dll',
-            'vendor/lib/libvips-42.dll',
-            'vendor/lib/libwebp-7.dll',
-            'vendor/lib/libxml2-2.dll',
-            'vendor/lib/zlib1.dll'
-          ]
-        }]
-      }]
-    ]
   }]
 }

binding.js

@@ -1,108 +0,0 @@
-'use strict';
-
-const fs = require('fs');
-const os = require('os');
-const path = require('path');
-
-const simpleGet = require('simple-get');
-const semver = require('semver');
-const tar = require('tar');
-const detectLibc = require('detect-libc');
-
-const agent = require('./lib/agent');
-const platform = require('./lib/platform');
-
-// Use NPM-provided environment variable where available, falling back to require-based method for Electron
-const minimumLibvipsVersion = process.env.npm_package_config_libvips || require('./package.json').config.libvips;
-
-const distBaseUrl = process.env.SHARP_DIST_BASE_URL || `https://github.com/lovell/sharp-libvips/releases/download/v${minimumLibvipsVersion}/`;
-
-// -- Helpers
-
-const unpack = function (tarPath, done) {
-  const vendorPath = path.join(__dirname, 'vendor');
-  fs.mkdirSync(vendorPath);
-  tar
-    .extract({
-      file: tarPath,
-      cwd: vendorPath,
-      strict: true
-    })
-    .then(done)
-    .catch(error);
-};
-
-const error = function (msg) {
-  if (msg instanceof Error) {
-    msg = msg.message;
-  }
-  process.stderr.write(`sharp: ${msg}\n`);
-  process.exit(1);
-};
-
-// -- Binary downloaders
-
-module.exports.download_vips = function () {
-  // Check for existing vendored binaries and verify platform matches
-  const currentPlatformId = platform();
-  try {
-    const vendorPlatformId = require(path.join(__dirname, 'vendor', 'platform.json'));
-    if (currentPlatformId === vendorPlatformId) {
-      return;
-    } else {
-      error(`'${vendorPlatformId}' binaries cannot be used on the '${currentPlatformId}' platform. Please remove the 'node_modules/sharp/vendor' directory and run 'npm install'.`);
-    }
-  } catch (err) {}
-  // Ensure Intel 64-bit or ARM
-  const arch = process.env.npm_config_arch || process.arch;
-  if (arch === 'ia32') {
-    error(`Intel Architecture 32-bit systems require manual installation of libvips >= ${minimumLibvipsVersion} - please see http://sharp.pixelplumbing.com/page/install`);
-  }
-  // Ensure glibc Linux
-  if (detectLibc.isNonGlibcLinux) {
-    error(`Use with ${detectLibc.family} libc requires manual installation of libvips >= ${minimumLibvipsVersion} - please see http://sharp.pixelplumbing.com/page/install`);
-  }
-  // Ensure glibc >= 2.13
-  if (detectLibc.family === detectLibc.GLIBC && detectLibc.version && semver.lt(`${detectLibc.version}.0`, '2.13.0')) {
-    error(`Use with glibc version ${detectLibc.version} requires manual installation of libvips >= ${minimumLibvipsVersion} - please see http://sharp.pixelplumbing.com/page/install`);
-  }
-  // Arch/platform-specific .tar.gz
-  const tarFilename = ['libvips', minimumLibvipsVersion, currentPlatformId].join('-') + '.tar.gz';
-  // Download to per-process temporary file
-  const tarPathTemp = path.join(os.tmpdir(), `${process.pid}-${tarFilename}`);
-  const tmpFile = fs.createWriteStream(tarPathTemp).on('close', function () {
-    unpack(tarPathTemp, function () {
-      // Attempt to remove temporary file
-      try {
-        fs.unlinkSync(tarPathTemp);
-      } catch (err) {}
-    });
-  });
-  const url = distBaseUrl + tarFilename;
-  const simpleGetOpt = {
-    url: url,
-    agent: agent()
-  };
-  simpleGet(simpleGetOpt, function (err, response) {
-    if (err) {
-      error(`${url} download failed: ${err.message}`);
-    }
-    if (response.statusCode !== 200) {
-      error(`${url} download failed: status ${response.statusCode}`);
-    }
-    response.pipe(tmpFile);
-  });
-};
-
-module.exports.use_global_vips = function () {
-  const globalVipsVersion = process.env.GLOBAL_VIPS_VERSION;
-  if (globalVipsVersion) {
-    const useGlobalVips = semver.gte(
-      globalVipsVersion,
-      minimumLibvipsVersion
-    );
-    process.stdout.write(useGlobalVips ? 'true' : 'false');
-  } else {
-    process.stdout.write('false');
-  }
-};

docs/README.md

@@ -0,0 +1,84 @@
+# sharp
+
+<img src="https://cdn.jsdelivr.net/gh/lovell/sharp@master/docs/image/sharp-logo.svg" width="160" height="160" alt="sharp logo" align="right">
+
+The typical use case for this high speed Node.js module
+is to convert large images in common formats to
+smaller, web-friendly JPEG, PNG, AVIF and WebP images of varying dimensions.
+
+Resizing an image is typically 4x-5x faster than using the
+quickest ImageMagick and GraphicsMagick settings
+due to its use of [libvips](https://github.com/libvips/libvips).
+
+Colour spaces, embedded ICC profiles and alpha transparency channels are all handled correctly.
+Lanczos resampling ensures quality is not sacrificed for speed.
+
+As well as image resizing, operations such as
+rotation, extraction, compositing and gamma correction are available.
+
+Most modern macOS, Windows and Linux systems running Node.js >= 12.13.0
+do not require any additional install or runtime dependencies.
+
+### Formats
+
+This module supports reading JPEG, PNG, WebP, AVIF, TIFF, GIF and SVG images.
+
+Output images can be in JPEG, PNG, WebP, AVIF and TIFF formats as well as uncompressed raw pixel data.
+
+Streams, Buffer objects and the filesystem can be used for input and output.
+
+A single input Stream can be split into multiple processing pipelines and output Streams.
+
+Deep Zoom image pyramids can be generated,
+suitable for use with "slippy map" tile viewers like
+[OpenSeadragon](https://github.com/openseadragon/openseadragon).
+
+### Fast
+
+This module is powered by the blazingly fast
+[libvips](https://github.com/libvips/libvips) image processing library,
+originally created in 1989 at Birkbeck College
+and currently maintained by a small team led by
+[John Cupitt](https://github.com/jcupitt).
+
+Only small regions of uncompressed image data
+are held in memory and processed at a time,
+taking full advantage of multiple CPU cores and L1/L2/L3 cache.
+
+Everything remains non-blocking thanks to _libuv_,
+no child processes are spawned and Promises/async/await are supported.
+
+### Optimal
+
+The features of `mozjpeg` and `pngquant` can be used
+to optimise the file size of JPEG and PNG images respectively,
+without having to invoke separate `imagemin` processes.
+
+Huffman tables are optimised when generating JPEG output images
+without having to use separate command line tools like
+[jpegoptim](https://github.com/tjko/jpegoptim) and
+[jpegtran](http://jpegclub.org/jpegtran/).
+
+PNG filtering is disabled by default,
+which for diagrams and line art often produces the same result
+as [pngcrush](https://pmt.sourceforge.io/pngcrush/).
+
+### Contributing
+
+A [guide for contributors](https://github.com/lovell/sharp/blob/master/.github/CONTRIBUTING.md)
+covers reporting bugs, requesting features and submitting code changes.
+
+### Licensing
+
+Copyright 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021 Lovell Fuller and contributors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+[https://www.apache.org/licenses/LICENSE-2.0](https://www.apache.org/licenses/LICENSE-2.0)
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

docs/api-channel.md

@@ -1,31 +1,84 @@
 <!-- Generated by documentation.js. Update this documentation by updating the source code. -->
 
-### Table of Contents
+## removeAlpha
 
--   [extractChannel](#extractchannel)
--   [joinChannel](#joinchannel)
--   [bandbool](#bandbool)
+Remove alpha channel, if any. This is a no-op if the image does not have an alpha channel.
+
+See also [flatten][1].
+
+### Examples
+
+```javascript
+sharp('rgba.png')
+  .removeAlpha()
+  .toFile('rgb.png', function(err, info) {
+    // rgb.png is a 3 channel image without an alpha channel
+  });
+```
+
+Returns **Sharp** 
+
+## ensureAlpha
+
+Ensure the output image has an alpha transparency channel.
+If missing, the added alpha channel will have the specified
+transparency level, defaulting to fully-opaque (1).
+This is a no-op if the image already has an alpha channel.
+
+### Parameters
+
+*   `alpha` **[number][2]** alpha transparency level (0=fully-transparent, 1=fully-opaque) (optional, default `1`)
+
+### Examples
+
+```javascript
+// rgba.png will be a 4 channel image with a fully-opaque alpha channel
+await sharp('rgb.jpg')
+  .ensureAlpha()
+  .toFile('rgba.png')
+```
+
+```javascript
+// rgba is a 4 channel image with a fully-transparent alpha channel
+const rgba = await sharp(rgb)
+  .ensureAlpha(0)
+  .toBuffer();
+```
+
+*   Throws **[Error][3]** Invalid alpha transparency level
+
+Returns **Sharp** 
+
+**Meta**
+
+*   **since**: 0.21.2
 
 ## extractChannel
 
 Extract a single channel from a multi-channel image.
 
-**Parameters**
+### Parameters
 
--   `channel` **([Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number) \| [String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String))** zero-indexed band number to extract, or `red`, `green` or `blue` as alternative to `0`, `1` or `2` respectively.
+*   `channel` **([number][2] | [string][4])** zero-indexed channel/band number to extract, or `red`, `green`, `blue` or `alpha`.
 
-**Examples**
+### Examples
 
 ```javascript
-sharp(input)
+// green.jpg is a greyscale image containing the green channel of the input
+await sharp(input)
   .extractChannel('green')
-  .toFile('input_green.jpg', function(err, info) {
-    // info.channels === 1
-    // input_green.jpg contains the green channel of the input image
-   });
+  .toFile('green.jpg');
 ```
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid channel
+```javascript
+// red1 is the red value of the first pixel, red2 the second pixel etc.
+const [red1, red2, ...] = await sharp(input)
+  .extractChannel(0)
+  .raw()
+  .toBuffer();
+```
+
+*   Throws **[Error][3]** Invalid channel
 
 Returns **Sharp** 
 
@@ -36,19 +89,20 @@ The meaning of the added channels depends on the output colourspace, set with `t
 By default the output image will be web-friendly sRGB, with additional channels interpreted as alpha channels.
 Channel ordering follows vips convention:
 
--   sRGB: 0: Red, 1: Green, 2: Blue, 3: Alpha.
--   CMYK: 0: Magenta, 1: Cyan, 2: Yellow, 3: Black, 4: Alpha.
+*   sRGB: 0: Red, 1: Green, 2: Blue, 3: Alpha.
+*   CMYK: 0: Magenta, 1: Cyan, 2: Yellow, 3: Black, 4: Alpha.
 
-Buffers may be any of the image formats supported by sharp: JPEG, PNG, WebP, GIF, SVG, TIFF or raw pixel image data.
+Buffers may be any of the image formats supported by sharp.
 For raw pixel input, the `options` object should contain a `raw` attribute, which follows the format of the attribute of the same name in the `sharp()` constructor.
 
-**Parameters**
+### Parameters
 
--   `images` **([Array](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Array)&lt;([String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String) \| [Buffer](https://nodejs.org/api/buffer.html))> | [String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String) \| [Buffer](https://nodejs.org/api/buffer.html))** one or more images (file paths, Buffers).
--   `options` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)** image options, see `sharp()` constructor.
+*   `images` **([Array][5]<([string][4] | [Buffer][6])> | [string][4] | [Buffer][6])** one or more images (file paths, Buffers).
+*   `options` **[Object][7]** image options, see `sharp()` constructor.
 
+<!---->
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+*   Throws **[Error][3]** Invalid parameters
 
 Returns **Sharp** 
 
@@ -56,11 +110,11 @@ Returns **Sharp**
 
 Perform a bitwise boolean operation on all input image channels (bands) to produce a single channel output image.
 
-**Parameters**
+### Parameters
 
--   `boolOp` **[String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String)** one of `and`, `or` or `eor` to perform that bitwise operation, like the C logic operators `&`, `|` and `^` respectively.
+*   `boolOp` **[string][4]** one of `and`, `or` or `eor` to perform that bitwise operation, like the C logic operators `&`, `|` and `^` respectively.
 
-**Examples**
+### Examples
 
 ```javascript
 sharp('3-channel-rgb-input.png')
@@ -72,6 +126,20 @@ sharp('3-channel-rgb-input.png')
   });
 ```
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+*   Throws **[Error][3]** Invalid parameters
 
 Returns **Sharp** 
+
+[1]: /api-operation#flatten
+
+[2]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number
+
+[3]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error
+
+[4]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String
+
+[5]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Array
+
+[6]: https://nodejs.org/api/buffer.html
+
+[7]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object

docs/api-colour.md

@@ -1,28 +1,17 @@
 <!-- Generated by documentation.js. Update this documentation by updating the source code. -->
 
-### Table of Contents
+## tint
 
--   [background](#background)
--   [greyscale](#greyscale)
--   [grayscale](#grayscale)
--   [toColourspace](#tocolourspace)
--   [toColorspace](#tocolorspace)
+Tint the image using the provided chroma while preserving the image luminance.
+An alpha channel may be present and will be unchanged by the operation.
 
-## background
+### Parameters
 
-Set the background for the `embed`, `flatten` and `extend` operations.
-The default background is `{r: 0, g: 0, b: 0, alpha: 1}`, black without transparency.
+*   `rgb` **([string][1] | [Object][2])** parsed by the [color][3] module to extract chroma values.
 
-Delegates to the _color_ module, which can throw an Error
-but is liberal in what it accepts, clipping values to sensible min/max.
-The alpha value is a float between `0` (transparent) and `1` (opaque).
+<!---->
 
-**Parameters**
-
--   `rgba` **([String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String) \| [Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object))** parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
-
-
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameter
+*   Throws **[Error][4]** Invalid parameter
 
 Returns **Sharp** 
 
@@ -35,9 +24,9 @@ This may be overridden by other sharp operations such as `toColourspace('b-w')`,
 which will produce an output image containing one color channel.
 An alpha channel may be present, and will be unchanged by the operation.
 
-**Parameters**
+### Parameters
 
--   `greyscale` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)**  (optional, default `true`)
+*   `greyscale` **[Boolean][5]**  (optional, default `true`)
 
 Returns **Sharp** 
 
@@ -45,9 +34,54 @@ Returns **Sharp**
 
 Alternative spelling of `greyscale`.
 
-**Parameters**
+### Parameters
 
--   `grayscale` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)**  (optional, default `true`)
+*   `grayscale` **[Boolean][5]**  (optional, default `true`)
+
+Returns **Sharp** 
+
+## pipelineColourspace
+
+Set the pipeline colourspace.
+
+The input image will be converted to the provided colourspace at the start of the pipeline.
+All operations will use this colourspace before converting to the output colourspace, as defined by [toColourspace][6].
+
+This feature is experimental and has not yet been fully-tested with all operations.
+
+### Parameters
+
+*   `colourspace` **[string][1]?** pipeline colourspace e.g. `rgb16`, `scrgb`, `lab`, `grey16` [...][7]
+
+### Examples
+
+```javascript
+// Run pipeline in 16 bits per channel RGB while converting final result to 8 bits per channel sRGB.
+await sharp(input)
+ .pipelineColourspace('rgb16')
+ .toColourspace('srgb')
+ .toFile('16bpc-pipeline-to-8bpc-output.png')
+```
+
+*   Throws **[Error][4]** Invalid parameters
+
+Returns **Sharp** 
+
+**Meta**
+
+*   **since**: 0.29.0
+
+## pipelineColorspace
+
+Alternative spelling of `pipelineColourspace`.
+
+### Parameters
+
+*   `colorspace` **[string][1]?** pipeline colorspace.
+
+<!---->
+
+*   Throws **[Error][4]** Invalid parameters
 
 Returns **Sharp** 
 
@@ -56,12 +90,20 @@ Returns **Sharp**
 Set the output colourspace.
 By default output image will be web-friendly sRGB, with additional channels interpreted as alpha channels.
 
-**Parameters**
+### Parameters
 
--   `colourspace` **[String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String)?** output colourspace e.g. `srgb`, `rgb`, `cmyk`, `lab`, `b-w` [...](https://github.com/jcupitt/libvips/blob/master/libvips/iofuncs/enumtypes.c#L568)
+*   `colourspace` **[string][1]?** output colourspace e.g. `srgb`, `rgb`, `cmyk`, `lab`, `b-w` [...][8]
 
+### Examples
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+```javascript
+// Output 16 bits per pixel RGB
+await sharp(input)
+ .toColourspace('rgb16')
+ .toFile('16-bpp.png')
+```
+
+*   Throws **[Error][4]** Invalid parameters
 
 Returns **Sharp** 
 
@@ -69,11 +111,28 @@ Returns **Sharp**
 
 Alternative spelling of `toColourspace`.
 
-**Parameters**
+### Parameters
 
--   `colorspace` **[String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String)?** output colorspace.
+*   `colorspace` **[string][1]?** output colorspace.
 
+<!---->
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+*   Throws **[Error][4]** Invalid parameters
 
 Returns **Sharp** 
+
+[1]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String
+
+[2]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object
+
+[3]: https://www.npmjs.org/package/color
+
+[4]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error
+
+[5]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean
+
+[6]: #tocolourspace
+
+[7]: https://github.com/libvips/libvips/blob/41cff4e9d0838498487a00623462204eb10ee5b8/libvips/iofuncs/enumtypes.c#L774
+
+[8]: https://github.com/libvips/libvips/blob/3c0bfdf74ce1dc37a6429bed47fa76f16e2cd70a/libvips/iofuncs/enumtypes.c#L777-L794

docs/api-composite.md

@@ -1,51 +1,60 @@
 <!-- Generated by documentation.js. Update this documentation by updating the source code. -->
 
-### Table of Contents
+## composite
 
--   [overlayWith](#overlaywith)
+Composite image(s) over the processed (resized, extracted etc.) image.
 
-## overlayWith
-
-Overlay (composite) an image over the processed (resized, extracted etc.) image.
-
-The overlay image must be the same size or smaller than the processed image.
+The images to composite must be the same size or smaller than the processed image.
 If both `top` and `left` options are provided, they take precedence over `gravity`.
 
-If the overlay image contains an alpha channel then composition with premultiplication will occur.
+The `blend` option can be one of `clear`, `source`, `over`, `in`, `out`, `atop`,
+`dest`, `dest-over`, `dest-in`, `dest-out`, `dest-atop`,
+`xor`, `add`, `saturate`, `multiply`, `screen`, `overlay`, `darken`, `lighten`,
+`colour-dodge`, `color-dodge`, `colour-burn`,`color-burn`,
+`hard-light`, `soft-light`, `difference`, `exclusion`.
 
-**Parameters**
+More information about blend modes can be found at
+[https://libvips.github.io/libvips/API/current/libvips-conversion.html#VipsBlendMode][1]
+and [https://www.cairographics.org/operators/][2]
 
--   `overlay` **([Buffer](https://nodejs.org/api/buffer.html) \| [String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String))** Buffer containing image data or String containing the path to an image file.
--   `options` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** 
-    -   `options.gravity` **[String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String)** gravity at which to place the overlay. (optional, default `'centre'`)
-    -   `options.top` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** the pixel offset from the top edge.
-    -   `options.left` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** the pixel offset from the left edge.
-    -   `options.tile` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** set to true to repeat the overlay image across the entire image with the given `gravity`. (optional, default `false`)
-    -   `options.cutout` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** set to true to apply only the alpha channel of the overlay image to the input image, giving the appearance of one image being cut out of another. (optional, default `false`)
-    -   `options.density` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** integral number representing the DPI for vector overlay image. (optional, default `72`)
-    -   `options.raw` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** describes overlay when using raw pixel data.
-        -   `options.raw.width` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-        -   `options.raw.height` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-        -   `options.raw.channels` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-    -   `options.create` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** describes a blank overlay to be created.
-        -   `options.create.width` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-        -   `options.create.height` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-        -   `options.create.channels` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 3-4
-        -   `options.create.background` **([String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String) \| [Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object))?** parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
+### Parameters
 
-**Examples**
+*   `images` **[Array][3]<[Object][4]>** Ordered list of images to composite
+
+    *   `images[].input` **([Buffer][5] | [String][6])?** Buffer containing image data, String containing the path to an image file, or Create object (see below)
+
+        *   `images[].input.create` **[Object][4]?** describes a blank overlay to be created.
+
+            *   `images[].input.create.width` **[Number][7]?** 
+            *   `images[].input.create.height` **[Number][7]?** 
+            *   `images[].input.create.channels` **[Number][7]?** 3-4
+            *   `images[].input.create.background` **([String][6] | [Object][4])?** parsed by the [color][8] module to extract values for red, green, blue and alpha.
+    *   `images[].blend` **[String][6]** how to blend this image with the image below. (optional, default `'over'`)
+    *   `images[].gravity` **[String][6]** gravity at which to place the overlay. (optional, default `'centre'`)
+    *   `images[].top` **[Number][7]?** the pixel offset from the top edge.
+    *   `images[].left` **[Number][7]?** the pixel offset from the left edge.
+    *   `images[].tile` **[Boolean][9]** set to true to repeat the overlay image across the entire image with the given `gravity`. (optional, default `false`)
+    *   `images[].premultiplied` **[Boolean][9]** set to true to avoid premultipling the image below. Equivalent to the `--premultiplied` vips option. (optional, default `false`)
+    *   `images[].density` **[Number][7]** number representing the DPI for vector overlay image. (optional, default `72`)
+    *   `images[].raw` **[Object][4]?** describes overlay when using raw pixel data.
+
+        *   `images[].raw.width` **[Number][7]?** 
+        *   `images[].raw.height` **[Number][7]?** 
+        *   `images[].raw.channels` **[Number][7]?** 
+    *   `images[].failOnError` **[boolean][9]** @see [constructor parameters][10] (optional, default `true`)
+    *   `images[].limitInputPixels` **([number][7] | [boolean][9])** @see [constructor parameters][10] (optional, default `268402689`)
+
+### Examples
 
 ```javascript
 sharp('input.png')
   .rotate(180)
   .resize(300)
-  .flatten()
-  .background('#ff6600')
-  .overlayWith('overlay.png', { gravity: sharp.gravity.southeast } )
+  .flatten( { background: '#ff6600' } )
+  .composite([{ input: 'overlay.png', gravity: 'southeast' }])
   .sharpen()
   .withMetadata()
-  .quality(90)
-  .webp()
+  .webp( { quality: 90 } )
   .toBuffer()
   .then(function(outputBuffer) {
     // outputBuffer contains upside down, 300px wide, alpha channel flattened
@@ -54,6 +63,32 @@ sharp('input.png')
   });
 ```
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+*   Throws **[Error][11]** Invalid parameters
 
 Returns **Sharp** 
+
+**Meta**
+
+*   **since**: 0.22.0
+
+[1]: https://libvips.github.io/libvips/API/current/libvips-conversion.html#VipsBlendMode
+
+[2]: https://www.cairographics.org/operators/
+
+[3]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Array
+
+[4]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object
+
+[5]: https://nodejs.org/api/buffer.html
+
+[6]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String
+
+[7]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number
+
+[8]: https://www.npmjs.org/package/color
+
+[9]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean
+
+[10]: /api-constructor#parameters
+
+[11]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error

docs/api-constructor.md

@@ -1,36 +1,58 @@
 <!-- Generated by documentation.js. Update this documentation by updating the source code. -->
 
-### Table of Contents
-
--   [Sharp](#sharp)
-    -   [format](#format)
-    -   [versions](#versions)
--   [queue](#queue)
-
 ## Sharp
 
-**Parameters**
+Constructor factory to create an instance of `sharp`, to which further methods are chained.
 
--   `input` **([Buffer](https://nodejs.org/api/buffer.html) \| [String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String))?** if present, can be
-     a Buffer containing JPEG, PNG, WebP, GIF, SVG, TIFF or raw pixel image data, or
-     a String containing the path to an JPEG, PNG, WebP, GIF, SVG or TIFF image file.
-     JPEG, PNG, WebP, GIF, SVG, TIFF or raw pixel image data can be streamed into the object when not present.
--   `options` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** if present, is an Object with optional attributes.
-    -   `options.failOnError` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** by default apply a "best effort"
-         to decode images, even if the data is corrupt or invalid. Set this flag to true
-         if you'd rather halt processing and raise an error when loading invalid images. (optional, default `false`)
-    -   `options.density` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** integral number representing the DPI for vector images. (optional, default `72`)
-    -   `options.raw` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** describes raw pixel input image data. See `raw()` for pixel ordering.
-        -   `options.raw.width` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-        -   `options.raw.height` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-        -   `options.raw.channels` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 1-4
-    -   `options.create` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** describes a new image to be created.
-        -   `options.create.width` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-        -   `options.create.height` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-        -   `options.create.channels` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 3-4
-        -   `options.create.background` **([String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String) \| [Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object))?** parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
+JPEG, PNG, WebP, AVIF or TIFF format image data can be streamed out from this object.
+When using Stream based output, derived attributes are available from the `info` event.
 
-**Examples**
+Non-critical problems encountered during processing are emitted as `warning` events.
+
+Implements the [stream.Duplex][1] class.
+
+### Parameters
+
+*   `input` **([Buffer][2] | [Uint8Array][3] | [Uint8ClampedArray][4] | [Int8Array][5] | [Uint16Array][6] | [Int16Array][7] | [Uint32Array][8] | [Int32Array][9] | [Float32Array][10] | [Float64Array][11] | [string][12])?** if present, can be
+    a Buffer / Uint8Array / Uint8ClampedArray containing JPEG, PNG, WebP, AVIF, GIF, SVG or TIFF image data, or
+    a TypedArray containing raw pixel image data, or
+    a String containing the filesystem path to an JPEG, PNG, WebP, AVIF, GIF, SVG or TIFF image file.
+    JPEG, PNG, WebP, AVIF, GIF, SVG, TIFF or raw pixel image data can be streamed into the object when not present.
+*   `options` **[Object][13]?** if present, is an Object with optional attributes.
+
+    *   `options.failOnError` **[boolean][14]** by default halt processing and raise an error when loading invalid images.
+        Set this flag to `false` if you'd rather apply a "best effort" to decode images, even if the data is corrupt or invalid. (optional, default `true`)
+    *   `options.limitInputPixels` **([number][15] | [boolean][14])** Do not process input images where the number of pixels
+        (width x height) exceeds this limit. Assumes image dimensions contained in the input metadata can be trusted.
+        An integral Number of pixels, zero or false to remove limit, true to use default limit of 268402689 (0x3FFF x 0x3FFF). (optional, default `268402689`)
+    *   `options.sequentialRead` **[boolean][14]** Set this to `true` to use sequential rather than random access where possible.
+        This can reduce memory usage and might improve performance on some systems. (optional, default `false`)
+    *   `options.density` **[number][15]** number representing the DPI for vector images in the range 1 to 100000. (optional, default `72`)
+    *   `options.pages` **[number][15]** number of pages to extract for multi-page input (GIF, WebP, AVIF, TIFF, PDF), use -1 for all pages. (optional, default `1`)
+    *   `options.page` **[number][15]** page number to start extracting from for multi-page input (GIF, WebP, AVIF, TIFF, PDF), zero based. (optional, default `0`)
+    *   `options.subifd` **[number][15]** subIFD (Sub Image File Directory) to extract for OME-TIFF, defaults to main image. (optional, default `-1`)
+    *   `options.level` **[number][15]** level to extract from a multi-level input (OpenSlide), zero based. (optional, default `0`)
+    *   `options.animated` **[boolean][14]** Set to `true` to read all frames/pages of an animated image (equivalent of setting `pages` to `-1`). (optional, default `false`)
+    *   `options.raw` **[Object][13]?** describes raw pixel input image data. See `raw()` for pixel ordering.
+
+        *   `options.raw.width` **[number][15]?** integral number of pixels wide.
+        *   `options.raw.height` **[number][15]?** integral number of pixels high.
+        *   `options.raw.channels` **[number][15]?** integral number of channels, between 1 and 4.
+        *   `options.raw.premultiplied` **[boolean][14]?** specifies that the raw input has already been premultiplied, set to `true`
+            to avoid sharp premultiplying the image. (optional, default `false`)
+    *   `options.create` **[Object][13]?** describes a new image to be created.
+
+        *   `options.create.width` **[number][15]?** integral number of pixels wide.
+        *   `options.create.height` **[number][15]?** integral number of pixels high.
+        *   `options.create.channels` **[number][15]?** integral number of channels, either 3 (RGB) or 4 (RGBA).
+        *   `options.create.background` **([string][12] | [Object][13])?** parsed by the [color][16] module to extract values for red, green, blue and alpha.
+        *   `options.create.noise` **[Object][13]?** describes a noise to be created.
+
+            *   `options.create.noise.type` **[string][12]?** type of generated noise, currently only `gaussian` is supported.
+            *   `options.create.noise.mean` **[number][15]?** mean of pixels in generated noise.
+            *   `options.create.noise.sigma` **[number][15]?** standard deviation of pixels in generated noise.
+
+### Examples
 
 ```javascript
 sharp('input.jpg')
@@ -61,7 +83,7 @@ sharp({
     width: 300,
     height: 200,
     channels: 4,
-    background: { r: 255, g: 0, b: 0, alpha: 128 }
+    background: { r: 255, g: 0, b: 0, alpha: 0.5 }
   }
 })
 .png()
@@ -69,43 +91,146 @@ sharp({
 .then( ... );
 ```
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
-
-Returns **[Sharp](#sharp)** 
-
-### format
-
-An Object containing nested boolean values representing the available input and output formats/methods.
-
-**Examples**
-
 ```javascript
-console.log(sharp.format);
+// Convert an animated GIF to an animated WebP
+await sharp('in.gif', { animated: true }).toFile('out.webp');
 ```
 
-Returns **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)** 
-
-### versions
-
-An Object containing the version numbers of libvips and its dependencies.
-
-**Examples**
-
 ```javascript
-console.log(sharp.versions);
-```
-
-## queue
-
-An EventEmitter that emits a `change` event when a task is either:
-
--   queued, waiting for _libuv_ to provide a worker thread
--   complete
-
-**Examples**
-
-```javascript
-sharp.queue.on('change', function(queueLength) {
-  console.log('Queue contains ' + queueLength + ' task(s)');
+// Read a raw array of pixels and save it to a png
+const input = Uint8Array.from([255, 255, 255, 0, 0, 0]); // or Uint8ClampedArray
+const image = sharp(input, {
+  // because the input does not contain its dimensions or how many channels it has
+  // we need to specify it in the constructor options
+  raw: {
+    width: 2,
+    height: 1,
+    channels: 3
+  }
 });
+await image.toFile('my-two-pixels.png');
 ```
+
+```javascript
+// Generate RGB Gaussian noise
+await sharp({
+  create: {
+    width: 300,
+    height: 200,
+    channels: 3,
+    noise: {
+      type: 'gaussian',
+      mean: 128,
+      sigma: 30
+    }
+ }
+}).toFile('noise.png');
+```
+
+*   Throws **[Error][17]** Invalid parameters
+
+Returns **[Sharp][18]** 
+
+## clone
+
+Take a "snapshot" of the Sharp instance, returning a new instance.
+Cloned instances inherit the input of their parent instance.
+This allows multiple output Streams and therefore multiple processing pipelines to share a single input Stream.
+
+### Examples
+
+```javascript
+const pipeline = sharp().rotate();
+pipeline.clone().resize(800, 600).pipe(firstWritableStream);
+pipeline.clone().extract({ left: 20, top: 20, width: 100, height: 100 }).pipe(secondWritableStream);
+readableStream.pipe(pipeline);
+// firstWritableStream receives auto-rotated, resized readableStream
+// secondWritableStream receives auto-rotated, extracted region of readableStream
+```
+
+```javascript
+// Create a pipeline that will download an image, resize it and format it to different files
+// Using Promises to know when the pipeline is complete
+const fs = require("fs");
+const got = require("got");
+const sharpStream = sharp({
+  failOnError: false
+});
+
+const promises = [];
+
+promises.push(
+  sharpStream
+    .clone()
+    .jpeg({ quality: 100 })
+    .toFile("originalFile.jpg")
+);
+
+promises.push(
+  sharpStream
+    .clone()
+    .resize({ width: 500 })
+    .jpeg({ quality: 80 })
+    .toFile("optimized-500.jpg")
+);
+
+promises.push(
+  sharpStream
+    .clone()
+    .resize({ width: 500 })
+    .webp({ quality: 80 })
+    .toFile("optimized-500.webp")
+);
+
+// https://github.com/sindresorhus/got#gotstreamurl-options
+got.stream("https://www.example.com/some-file.jpg").pipe(sharpStream);
+
+Promise.all(promises)
+  .then(res => { console.log("Done!", res); })
+  .catch(err => {
+    console.error("Error processing files, let's clean it up", err);
+    try {
+      fs.unlinkSync("originalFile.jpg");
+      fs.unlinkSync("optimized-500.jpg");
+      fs.unlinkSync("optimized-500.webp");
+    } catch (e) {}
+  });
+```
+
+Returns **[Sharp][18]** 
+
+[1]: http://nodejs.org/api/stream.html#stream_class_stream_duplex
+
+[2]: https://nodejs.org/api/buffer.html
+
+[3]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Uint8Array
+
+[4]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Uint8ClampedArray
+
+[5]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Int8Array
+
+[6]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Uint16Array
+
+[7]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Int16Array
+
+[8]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Uint32Array
+
+[9]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Int32Array
+
+[10]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Float32Array
+
+[11]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Float64Array
+
+[12]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String
+
+[13]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object
+
+[14]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean
+
+[15]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number
+
+[16]: https://www.npmjs.org/package/color
+
+[17]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error
+
+[18]: #sharp

docs/api-input.md

@@ -1,57 +1,43 @@
 <!-- Generated by documentation.js. Update this documentation by updating the source code. -->
 
-### Table of Contents
-
--   [clone](#clone)
--   [metadata](#metadata)
--   [stats](#stats)
--   [limitInputPixels](#limitinputpixels)
--   [sequentialRead](#sequentialread)
-
-## clone
-
-Take a "snapshot" of the Sharp instance, returning a new instance.
-Cloned instances inherit the input of their parent instance.
-This allows multiple output Streams and therefore multiple processing pipelines to share a single input Stream.
-
-**Examples**
-
-```javascript
-const pipeline = sharp().rotate();
-pipeline.clone().resize(800, 600).pipe(firstWritableStream);
-pipeline.clone().extract({ left: 20, top: 20, width: 100, height: 100 }).pipe(secondWritableStream);
-readableStream.pipe(pipeline);
-// firstWritableStream receives auto-rotated, resized readableStream
-// secondWritableStream receives auto-rotated, extracted region of readableStream
-```
-
-Returns **Sharp** 
-
 ## metadata
 
 Fast access to (uncached) image metadata without decoding any compressed image data.
-A Promises/A+ promise is returned when `callback` is not provided.
+A `Promise` is returned when `callback` is not provided.
 
--   `format`: Name of decoder used to decompress image data e.g. `jpeg`, `png`, `webp`, `gif`, `svg`
--   `width`: Number of pixels wide
--   `height`: Number of pixels high
--   `space`: Name of colour space interpretation e.g. `srgb`, `rgb`, `cmyk`, `lab`, `b-w` [...](https://github.com/jcupitt/libvips/blob/master/libvips/iofuncs/enumtypes.c#L636)
--   `channels`: Number of bands e.g. `3` for sRGB, `4` for CMYK
--   `depth`: Name of pixel depth format e.g. `uchar`, `char`, `ushort`, `float` [...](https://github.com/jcupitt/libvips/blob/master/libvips/iofuncs/enumtypes.c#L672)
--   `density`: Number of pixels per inch (DPI), if present
--   `hasProfile`: Boolean indicating the presence of an embedded ICC profile
--   `hasAlpha`: Boolean indicating the presence of an alpha transparency channel
--   `orientation`: Number value of the EXIF Orientation header, if present
--   `exif`: Buffer containing raw EXIF data, if present
--   `icc`: Buffer containing raw [ICC](https://www.npmjs.com/package/icc) profile data, if present
--   `iptc`: Buffer containing raw IPTC data, if present
--   `xmp`: Buffer containing raw XMP data, if present
+*   `format`: Name of decoder used to decompress image data e.g. `jpeg`, `png`, `webp`, `gif`, `svg`
+*   `size`: Total size of image in bytes, for Stream and Buffer input only
+*   `width`: Number of pixels wide (EXIF orientation is not taken into consideration)
+*   `height`: Number of pixels high (EXIF orientation is not taken into consideration)
+*   `space`: Name of colour space interpretation e.g. `srgb`, `rgb`, `cmyk`, `lab`, `b-w` [...][1]
+*   `channels`: Number of bands e.g. `3` for sRGB, `4` for CMYK
+*   `depth`: Name of pixel depth format e.g. `uchar`, `char`, `ushort`, `float` [...][2]
+*   `density`: Number of pixels per inch (DPI), if present
+*   `chromaSubsampling`: String containing JPEG chroma subsampling, `4:2:0` or `4:4:4` for RGB, `4:2:0:4` or `4:4:4:4` for CMYK
+*   `isProgressive`: Boolean indicating whether the image is interlaced using a progressive scan
+*   `pages`: Number of pages/frames contained within the image, with support for TIFF, HEIF, PDF, animated GIF and animated WebP
+*   `pageHeight`: Number of pixels high each page in a multi-page image will be.
+*   `loop`: Number of times to loop an animated image, zero refers to a continuous loop.
+*   `delay`: Delay in ms between each page in an animated image, provided as an array of integers.
+*   `pagePrimary`: Number of the primary page in a HEIF image
+*   `levels`: Details of each level in a multi-level image provided as an array of objects, requires libvips compiled with support for OpenSlide
+*   `subifds`: Number of Sub Image File Directories in an OME-TIFF image
+*   `background`: Default background colour, if present, for PNG (bKGD) and GIF images, either an RGB Object or a single greyscale value
+*   `compression`: The encoder used to compress an HEIF file, `av1` (AVIF) or `hevc` (HEIC)
+*   `hasProfile`: Boolean indicating the presence of an embedded ICC profile
+*   `hasAlpha`: Boolean indicating the presence of an alpha transparency channel
+*   `orientation`: Number value of the EXIF Orientation header, if present
+*   `exif`: Buffer containing raw EXIF data, if present
+*   `icc`: Buffer containing raw [ICC][3] profile data, if present
+*   `iptc`: Buffer containing raw IPTC data, if present
+*   `xmp`: Buffer containing raw XMP data, if present
+*   `tifftagPhotoshop`: Buffer containing raw TIFFTAG_PHOTOSHOP data, if present
 
-**Parameters**
+### Parameters
 
--   `callback` **[Function](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/function)?** called with the arguments `(err, metadata)`
+*   `callback` **[Function][4]?** called with the arguments `(err, metadata)`
 
-**Examples**
+### Examples
 
 ```javascript
 const image = sharp(inputJpg);
@@ -68,31 +54,37 @@ image
   });
 ```
 
-Returns **([Promise](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Promise)&lt;[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)> | Sharp)** 
+Returns **([Promise][5]<[Object][6]> | Sharp)** 
 
 ## stats
 
 Access to pixel-derived image statistics for every channel in the image.
-A Promise is returned when `callback` is not provided.
+A `Promise` is returned when `callback` is not provided.
 
--   `channels`: Array of channel statistics for each channel in the image. Each channel statistic contains
-    -   `min` (minimum value in the channel)
-    -   `max` (maximum value in the channel)
-    -   `sum` (sum of all values in a channel)
-    -   `squaresSum` (sum of squared values in a channel)
-    -   `mean` (mean of the values in a channel)
-    -   `stdev` (standard deviation for the values in a channel)
-    -   `minX` (x-coordinate of one of the pixel where the minimum lies)
-    -   `minY` (y-coordinate of one of the pixel where the minimum lies)
-    -   `maxX` (x-coordinate of one of the pixel where the maximum lies)
-    -   `maxY` (y-coordinate of one of the pixel where the maximum lies)
--   `isOpaque`: Value to identify if the image is opaque or transparent, based on the presence and use of alpha channel
+*   `channels`: Array of channel statistics for each channel in the image. Each channel statistic contains
+    *   `min` (minimum value in the channel)
+    *   `max` (maximum value in the channel)
+    *   `sum` (sum of all values in a channel)
+    *   `squaresSum` (sum of squared values in a channel)
+    *   `mean` (mean of the values in a channel)
+    *   `stdev` (standard deviation for the values in a channel)
+    *   `minX` (x-coordinate of one of the pixel where the minimum lies)
+    *   `minY` (y-coordinate of one of the pixel where the minimum lies)
+    *   `maxX` (x-coordinate of one of the pixel where the maximum lies)
+    *   `maxY` (y-coordinate of one of the pixel where the maximum lies)
+*   `isOpaque`: Is the image fully opaque? Will be `true` if the image has no alpha channel or if every pixel is fully opaque.
+*   `entropy`: Histogram-based estimation of greyscale entropy, discarding alpha channel if any (experimental)
+*   `sharpness`: Estimation of greyscale sharpness based on the standard deviation of a Laplacian convolution, discarding alpha channel if any (experimental)
+*   `dominant`: Object containing most dominant sRGB colour based on a 4096-bin 3D histogram (experimental)
 
-**Parameters**
+**Note**: Statistics are derived from the original input image. Any operations performed on the image must first be
+written to a buffer in order to run `stats` on the result (see third example).
 
--   `callback` **[Function](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/function)?** called with the arguments `(err, stats)`
+### Parameters
 
-**Examples**
+*   `callback` **[Function][4]?** called with the arguments `(err, stats)`
+
+### Examples
 
 ```javascript
 const image = sharp(inputJpg);
@@ -103,32 +95,29 @@ image
   });
 ```
 
-Returns **[Promise](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Promise)&lt;[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)>** 
+```javascript
+const { entropy, sharpness, dominant } = await sharp(input).stats();
+const { r, g, b } = dominant;
+```
 
-## limitInputPixels
+```javascript
+const image = sharp(input);
+// store intermediate result
+const part = await image.extract(region).toBuffer();
+// create new instance to obtain statistics of extracted region
+const stats = await sharp(part).stats();
+```
 
-Do not process input images where the number of pixels (width _ height) exceeds this limit.
-Assumes image dimensions contained in the input metadata can be trusted.
-The default limit is 268402689 (0x3FFF _ 0x3FFF) pixels.
+Returns **[Promise][5]<[Object][6]>** 
 
-**Parameters**
+[1]: https://libvips.github.io/libvips/API/current/VipsImage.html#VipsInterpretation
 
--   `limit` **([Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number) \| [Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean))** an integral Number of pixels, zero or false to remove limit, true to use default limit.
+[2]: https://libvips.github.io/libvips/API/current/VipsImage.html#VipsBandFormat
 
+[3]: https://www.npmjs.com/package/icc
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid limit
+[4]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/function
 
-Returns **Sharp** 
+[5]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Promise
 
-## sequentialRead
-
-An advanced setting that switches the libvips access method to `VIPS_ACCESS_SEQUENTIAL`.
-This will reduce memory usage and can improve performance on some systems.
-
-The default behaviour _before_ function call is `false`, meaning the libvips access method is not sequential.
-
-**Parameters**
-
--   `sequentialRead` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)**  (optional, default `true`)
-
-Returns **Sharp** 
+[6]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object

docs/api-operation.md

@@ -1,33 +1,16 @@
 <!-- Generated by documentation.js. Update this documentation by updating the source code. -->
 
-### Table of Contents
-
--   [rotate](#rotate)
--   [extract](#extract)
--   [flip](#flip)
--   [flop](#flop)
--   [sharpen](#sharpen)
--   [blur](#blur)
--   [extend](#extend)
--   [flatten](#flatten)
--   [trim](#trim)
--   [gamma](#gamma)
--   [negate](#negate)
--   [normalise](#normalise)
--   [normalize](#normalize)
--   [convolve](#convolve)
--   [threshold](#threshold)
--   [boolean](#boolean)
--   [linear](#linear)
-
 ## rotate
 
 Rotate the output image by either an explicit angle
 or auto-orient based on the EXIF `Orientation` tag.
 
-If an angle is provided, it is converted to a valid 90/180/270deg rotation.
+If an angle is provided, it is converted to a valid positive degree rotation.
 For example, `-450` will produce a 270deg rotation.
 
+When rotating by an angle other than a multiple of 90,
+the background colour can be provided with the `background` option.
+
 If no angle is provided, it is determined from the EXIF data.
 Mirroring is supported and may infer the use of a flip operation.
 
@@ -36,11 +19,14 @@ The use of `rotate` implies the removal of the EXIF `Orientation` tag, if any.
 Method order is important when both rotating and extracting regions,
 for example `rotate(x).extract(y)` will produce a different result to `extract(y).rotate(x)`.
 
-**Parameters**
+### Parameters
 
--   `angle` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** angle of rotation, must be a multiple of 90. (optional, default `auto`)
+*   `angle` **[number][1]** angle of rotation. (optional, default `auto`)
+*   `options` **[Object][2]?** if present, is an Object with optional attributes.
 
-**Examples**
+    *   `options.background` **([string][3] | [Object][2])** parsed by the [color][4] module to extract values for red, green, blue and alpha. (optional, default `"#000000"`)
+
+### Examples
 
 ```javascript
 const pipeline = sharp()
@@ -54,47 +40,7 @@ const pipeline = sharp()
 readableStream.pipe(pipeline);
 ```
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
-
-Returns **Sharp** 
-
-## extract
-
-Extract a region of the image.
-
--   Use `extract` before `resize` for pre-resize extraction.
--   Use `extract` after `resize` for post-resize extraction.
--   Use `extract` before and after for both.
-
-**Parameters**
-
--   `options` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)** 
-    -   `options.left` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** zero-indexed offset from left edge
-    -   `options.top` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** zero-indexed offset from top edge
-    -   `options.width` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** dimension of extracted image
-    -   `options.height` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** dimension of extracted image
-
-**Examples**
-
-```javascript
-sharp(input)
-  .extract({ left: left, top: top, width: width, height: height })
-  .toFile(output, function(err) {
-    // Extract a region of the input image, saving in the same format.
-  });
-```
-
-```javascript
-sharp(input)
-  .extract({ left: leftOffsetPre, top: topOffsetPre, width: widthPre, height: heightPre })
-  .resize(width, height)
-  .extract({ left: leftOffsetPost, top: topOffsetPost, width: widthPost, height: heightPost })
-  .toFile(output, function(err) {
-    // Extract a region, resize, then extract from the resized image
-  });
-```
-
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+*   Throws **[Error][5]** Invalid parameters
 
 Returns **Sharp** 
 
@@ -103,9 +49,9 @@ Returns **Sharp**
 Flip the image about the vertical Y axis. This always occurs after rotation, if any.
 The use of `flip` implies the removal of the EXIF `Orientation` tag, if any.
 
-**Parameters**
+### Parameters
 
--   `flip` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)**  (optional, default `true`)
+*   `flip` **[Boolean][6]**  (optional, default `true`)
 
 Returns **Sharp** 
 
@@ -114,12 +60,68 @@ Returns **Sharp**
 Flop the image about the horizontal X axis. This always occurs after rotation, if any.
 The use of `flop` implies the removal of the EXIF `Orientation` tag, if any.
 
-**Parameters**
+### Parameters
 
--   `flop` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)**  (optional, default `true`)
+*   `flop` **[Boolean][6]**  (optional, default `true`)
 
 Returns **Sharp** 
 
+## affine
+
+Perform an affine transform on an image. This operation will always occur after resizing, extraction and rotation, if any.
+
+You must provide an array of length 4 or a 2x2 affine transformation matrix.
+By default, new pixels are filled with a black background. You can provide a background color with the `background` option.
+A particular interpolator may also be specified. Set the `interpolator` option to an attribute of the `sharp.interpolator` Object e.g. `sharp.interpolator.nohalo`.
+
+In the case of a 2x2 matrix, the transform is:
+
+*   X = `matrix[0, 0]` \* (x + `idx`) + `matrix[0, 1]` \* (y + `idy`) + `odx`
+*   Y = `matrix[1, 0]` \* (x + `idx`) + `matrix[1, 1]` \* (y + `idy`) + `ody`
+
+where:
+
+*   x and y are the coordinates in input image.
+*   X and Y are the coordinates in output image.
+*   (0,0) is the upper left corner.
+
+### Parameters
+
+*   `matrix` **([Array][7]<[Array][7]<[number][1]>> | [Array][7]<[number][1]>)** affine transformation matrix
+*   `options` **[Object][2]?** if present, is an Object with optional attributes.
+
+    *   `options.background` **([String][3] | [Object][2])** parsed by the [color][4] module to extract values for red, green, blue and alpha. (optional, default `"#000000"`)
+    *   `options.idx` **[Number][1]** input horizontal offset (optional, default `0`)
+    *   `options.idy` **[Number][1]** input vertical offset (optional, default `0`)
+    *   `options.odx` **[Number][1]** output horizontal offset (optional, default `0`)
+    *   `options.ody` **[Number][1]** output vertical offset (optional, default `0`)
+    *   `options.interpolator` **[String][3]** interpolator (optional, default `sharp.interpolators.bicubic`)
+
+### Examples
+
+```javascript
+const pipeline = sharp()
+  .affine([[1, 0.3], [0.1, 0.7]], {
+     background: 'white',
+     interpolate: sharp.interpolators.nohalo
+  })
+  .toBuffer((err, outputBuffer, info) => {
+     // outputBuffer contains the transformed image
+     // info.width and info.height contain the new dimensions
+  });
+
+inputStream
+  .pipe(pipeline);
+```
+
+*   Throws **[Error][5]** Invalid parameters
+
+Returns **Sharp** 
+
+**Meta**
+
+*   **since**: 0.27.0
+
 ## sharpen
 
 Sharpen the image.
@@ -127,14 +129,30 @@ When used without parameters, performs a fast, mild sharpen of the output image.
 When a `sigma` is provided, performs a slower, more accurate sharpen of the L channel in the LAB colour space.
 Separate control over the level of sharpening in "flat" and "jagged" areas is available.
 
-**Parameters**
+### Parameters
 
--   `sigma` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** the sigma of the Gaussian mask, where `sigma = 1 + radius / 2`.
--   `flat` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** the level of sharpening to apply to "flat" areas. (optional, default `1.0`)
--   `jagged` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** the level of sharpening to apply to "jagged" areas. (optional, default `2.0`)
+*   `sigma` **[number][1]?** the sigma of the Gaussian mask, where `sigma = 1 + radius / 2`.
+*   `flat` **[number][1]** the level of sharpening to apply to "flat" areas. (optional, default `1.0`)
+*   `jagged` **[number][1]** the level of sharpening to apply to "jagged" areas. (optional, default `2.0`)
 
+<!---->
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+*   Throws **[Error][5]** Invalid parameters
+
+Returns **Sharp** 
+
+## median
+
+Apply median filter.
+When used without parameters the default window is 3x3.
+
+### Parameters
+
+*   `size` **[number][1]** square mask size: size x size (optional, default `3`)
+
+<!---->
+
+*   Throws **[Error][5]** Invalid parameters
 
 Returns **Sharp** 
 
@@ -144,64 +162,35 @@ Blur the image.
 When used without parameters, performs a fast, mild blur of the output image.
 When a `sigma` is provided, performs a slower, more accurate Gaussian blur.
 
-**Parameters**
+### Parameters
 
--   `sigma` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** a value between 0.3 and 1000 representing the sigma of the Gaussian mask, where `sigma = 1 + radius / 2`.
+*   `sigma` **[number][1]?** a value between 0.3 and 1000 representing the sigma of the Gaussian mask, where `sigma = 1 + radius / 2`.
 
+<!---->
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
-
-Returns **Sharp** 
-
-## extend
-
-Extends/pads the edges of the image with the colour provided to the `background` method.
-This operation will always occur after resizing and extraction, if any.
-
-**Parameters**
-
--   `extend` **([Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number) \| [Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object))** single pixel count to add to all edges or an Object with per-edge counts
-    -   `extend.top` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-    -   `extend.left` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-    -   `extend.bottom` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-    -   `extend.right` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-
-**Examples**
-
-```javascript
-// Resize to 140 pixels wide, then add 10 transparent pixels
-// to the top, left and right edges and 20 to the bottom edge
-sharp(input)
-  .resize(140)
-  .background({r: 0, g: 0, b: 0, alpha: 0})
-  .extend({top: 10, bottom: 20, left: 10, right: 10})
-  ...
-```
-
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+*   Throws **[Error][5]** Invalid parameters
 
 Returns **Sharp** 
 
 ## flatten
 
-Merge alpha transparency channel, if any, with `background`.
+Merge alpha transparency channel, if any, with a background, then remove the alpha channel.
 
-**Parameters**
+See also [removeAlpha][8].
 
--   `flatten` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)**  (optional, default `true`)
+### Parameters
 
-Returns **Sharp** 
+*   `options` **[Object][2]?** 
 
-## trim
+    *   `options.background` **([string][3] | [Object][2])** background colour, parsed by the [color][4] module, defaults to black. (optional, default `{r:0,g:0,b:0}`)
 
-Trim "boring" pixels from all edges that contain values within a percentage similarity of the top-left pixel.
+### Examples
 
-**Parameters**
-
--   `tolerance` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** value between 1 and 99 representing the percentage similarity. (optional, default `10`)
-
-
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+```javascript
+await sharp(rgbaInput)
+  .flatten({ background: '#F0A703' })
+  .toBuffer();
+```
 
 Returns **Sharp** 
 
@@ -213,12 +202,16 @@ This can improve the perceived brightness of a resized image in non-linear colou
 JPEG and WebP input images will not take advantage of the shrink-on-load performance optimisation
 when applying a gamma correction.
 
-**Parameters**
+Supply a second argument to use a different output gamma value, otherwise the first value is used in both cases.
 
--   `gamma` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** value between 1.0 and 3.0. (optional, default `2.2`)
+### Parameters
 
+*   `gamma` **[number][1]** value between 1.0 and 3.0. (optional, default `2.2`)
+*   `gammaOut` **[number][1]?** value between 1.0 and 3.0. (optional, defaults to same as `gamma`)
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+<!---->
+
+*   Throws **[Error][5]** Invalid parameters
 
 Returns **Sharp** 
 
@@ -226,9 +219,11 @@ Returns **Sharp**
 
 Produce the "negative" of the image.
 
-**Parameters**
+### Parameters
 
--   `negate` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)**  (optional, default `true`)
+*   `options` **[Object][2]?** 
+
+    *   `options.alpha` **[Boolean][6]** Whether or not to negate any alpha channel (optional, default `true`)
 
 Returns **Sharp** 
 
@@ -236,9 +231,9 @@ Returns **Sharp**
 
 Enhance output image contrast by stretching its luminance to cover the full dynamic range.
 
-**Parameters**
+### Parameters
 
--   `normalise` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)**  (optional, default `true`)
+*   `normalise` **[Boolean][6]**  (optional, default `true`)
 
 Returns **Sharp** 
 
@@ -246,26 +241,54 @@ Returns **Sharp**
 
 Alternative spelling of normalise.
 
-**Parameters**
+### Parameters
 
--   `normalize` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)**  (optional, default `true`)
+*   `normalize` **[Boolean][6]**  (optional, default `true`)
 
 Returns **Sharp** 
 
+## clahe
+
+Perform contrast limiting adaptive histogram equalization
+[CLAHE][9].
+
+This will, in general, enhance the clarity of the image by bringing out darker details.
+
+### Parameters
+
+*   `options` **[Object][2]** 
+
+    *   `options.width` **[number][1]** integer width of the region in pixels.
+    *   `options.height` **[number][1]** integer height of the region in pixels.
+    *   `options.maxSlope` **[number][1]** maximum value for the slope of the
+        cumulative histogram. A value of 0 disables contrast limiting. Valid values
+        are integers in the range 0-100 (inclusive) (optional, default `3`)
+
+<!---->
+
+*   Throws **[Error][5]** Invalid parameters
+
+Returns **Sharp** 
+
+**Meta**
+
+*   **since**: 0.28.3
+
 ## convolve
 
 Convolve the image with the specified kernel.
 
-**Parameters**
+### Parameters
 
--   `kernel` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)** 
-    -   `kernel.width` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** width of the kernel in pixels.
-    -   `kernel.height` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** width of the kernel in pixels.
-    -   `kernel.kernel` **[Array](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Array)&lt;[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)>** Array of length `width*height` containing the kernel values.
-    -   `kernel.scale` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** the scale of the kernel in pixels. (optional, default `sum`)
-    -   `kernel.offset` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** the offset of the kernel in pixels. (optional, default `0`)
+*   `kernel` **[Object][2]** 
 
-**Examples**
+    *   `kernel.width` **[number][1]** width of the kernel in pixels.
+    *   `kernel.height` **[number][1]** height of the kernel in pixels.
+    *   `kernel.kernel` **[Array][7]<[number][1]>** Array of length `width*height` containing the kernel values.
+    *   `kernel.scale` **[number][1]** the scale of the kernel in pixels. (optional, default `sum`)
+    *   `kernel.offset` **[number][1]** the offset of the kernel in pixels. (optional, default `0`)
+
+### Examples
 
 ```javascript
 sharp(input)
@@ -281,23 +304,25 @@ sharp(input)
   });
 ```
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+*   Throws **[Error][5]** Invalid parameters
 
 Returns **Sharp** 
 
 ## threshold
 
-Any pixel value greather than or equal to the threshold value will be set to 255, otherwise it will be set to 0.
+Any pixel value greater than or equal to the threshold value will be set to 255, otherwise it will be set to 0.
 
-**Parameters**
+### Parameters
 
--   `threshold` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** a value in the range 0-255 representing the level at which the threshold will be applied. (optional, default `128`)
--   `options` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** 
-    -   `options.greyscale` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** convert to single channel greyscale. (optional, default `true`)
-    -   `options.grayscale` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** alternative spelling for greyscale. (optional, default `true`)
+*   `threshold` **[number][1]** a value in the range 0-255 representing the level at which the threshold will be applied. (optional, default `128`)
+*   `options` **[Object][2]?** 
 
+    *   `options.greyscale` **[Boolean][6]** convert to single channel greyscale. (optional, default `true`)
+    *   `options.grayscale` **[Boolean][6]** alternative spelling for greyscale. (optional, default `true`)
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+<!---->
+
+*   Throws **[Error][5]** Invalid parameters
 
 Returns **Sharp** 
 
@@ -308,18 +333,21 @@ Perform a bitwise boolean operation with operand image.
 This operation creates an output image where each pixel is the result of
 the selected bitwise boolean `operation` between the corresponding pixels of the input images.
 
-**Parameters**
+### Parameters
 
--   `operand` **([Buffer](https://nodejs.org/api/buffer.html) \| [String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String))** Buffer containing image data or String containing the path to an image file.
--   `operator` **[String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String)** one of `and`, `or` or `eor` to perform that bitwise operation, like the C logic operators `&`, `|` and `^` respectively.
--   `options` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** 
-    -   `options.raw` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** describes operand when using raw pixel data.
-        -   `options.raw.width` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-        -   `options.raw.height` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
-        -   `options.raw.channels` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
+*   `operand` **([Buffer][10] | [string][3])** Buffer containing image data or string containing the path to an image file.
+*   `operator` **[string][3]** one of `and`, `or` or `eor` to perform that bitwise operation, like the C logic operators `&`, `|` and `^` respectively.
+*   `options` **[Object][2]?** 
 
+    *   `options.raw` **[Object][2]?** describes operand when using raw pixel data.
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+        *   `options.raw.width` **[number][1]?** 
+        *   `options.raw.height` **[number][1]?** 
+        *   `options.raw.channels` **[number][1]?** 
+
+<!---->
+
+*   Throws **[Error][5]** Invalid parameters
 
 Returns **Sharp** 
 
@@ -327,12 +355,113 @@ Returns **Sharp**
 
 Apply the linear formula a \* input + b to the image (levels adjustment)
 
-**Parameters**
+### Parameters
 
--   `a` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** multiplier (optional, default `1.0`)
--   `b` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** offset (optional, default `0.0`)
+*   `a` **[number][1]** multiplier (optional, default `1.0`)
+*   `b` **[number][1]** offset (optional, default `0.0`)
 
+<!---->
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+*   Throws **[Error][5]** Invalid parameters
 
 Returns **Sharp** 
+
+## recomb
+
+Recomb the image with the specified matrix.
+
+### Parameters
+
+*   `inputMatrix` **[Array][7]<[Array][7]<[number][1]>>** 3x3 Recombination matrix
+
+### Examples
+
+```javascript
+sharp(input)
+  .recomb([
+   [0.3588, 0.7044, 0.1368],
+   [0.2990, 0.5870, 0.1140],
+   [0.2392, 0.4696, 0.0912],
+  ])
+  .raw()
+  .toBuffer(function(err, data, info) {
+    // data contains the raw pixel data after applying the recomb
+    // With this example input, a sepia filter has been applied
+  });
+```
+
+*   Throws **[Error][5]** Invalid parameters
+
+Returns **Sharp** 
+
+**Meta**
+
+*   **since**: 0.21.1
+
+## modulate
+
+Transforms the image using brightness, saturation, hue rotation, and lightness.
+Brightness and lightness both operate on luminance, with the difference being that
+brightness is multiplicative whereas lightness is additive.
+
+### Parameters
+
+*   `options` **[Object][2]?** 
+
+    *   `options.brightness` **[number][1]?** Brightness multiplier
+    *   `options.saturation` **[number][1]?** Saturation multiplier
+    *   `options.hue` **[number][1]?** Degrees for hue rotation
+    *   `options.lightness` **[number][1]?** Lightness addend
+
+### Examples
+
+```javascript
+sharp(input)
+  .modulate({
+    brightness: 2 // increase brightness by a factor of 2
+  });
+
+sharp(input)
+  .modulate({
+    hue: 180 // hue-rotate by 180 degrees
+  });
+
+sharp(input)
+  .modulate({
+    lightness: 50 // increase lightness by +50
+  });
+
+// decreate brightness and saturation while also hue-rotating by 90 degrees
+sharp(input)
+  .modulate({
+    brightness: 0.5,
+    saturation: 0.5,
+    hue: 90
+  });
+```
+
+Returns **Sharp** 
+
+**Meta**
+
+*   **since**: 0.22.1
+
+[1]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number
+
+[2]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object
+
+[3]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String
+
+[4]: https://www.npmjs.org/package/color
+
+[5]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error
+
+[6]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean
+
+[7]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Array
+
+[8]: /api-channel#removealpha
+
+[9]: https://en.wikipedia.org/wiki/Adaptive_histogram_equalization#Contrast_Limited_AHE
+
+[10]: https://nodejs.org/api/buffer.html

docs/api-output.md

@@ -1,160 +1,161 @@
 <!-- Generated by documentation.js. Update this documentation by updating the source code. -->
 
-### Table of Contents
-
--   [toFile](#tofile)
--   [toBuffer](#tobuffer)
--   [withMetadata](#withmetadata)
--   [jpeg](#jpeg)
--   [png](#png)
--   [webp](#webp)
--   [tiff](#tiff)
--   [raw](#raw)
--   [toFormat](#toformat)
--   [tile](#tile)
-
 ## toFile
 
 Write output image data to a file.
 
 If an explicit output format is not selected, it will be inferred from the extension,
-with JPEG, PNG, WebP, TIFF, DZI, and libvips' V format supported.
+with JPEG, PNG, WebP, AVIF, TIFF, DZI, and libvips' V format supported.
 Note that raw pixel data is only supported for buffer output.
 
+By default all metadata will be removed, which includes EXIF-based orientation.
+See [withMetadata][1] for control over this.
+
+The caller is responsible for ensuring directory structures and permissions exist.
+
 A `Promise` is returned when `callback` is not provided.
 
-**Parameters**
+### Parameters
 
--   `fileOut` **[String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String)** the path to write the image data to.
--   `callback` **[Function](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/function)?** called on completion with two arguments `(err, info)`.
+*   `fileOut` **[string][2]** the path to write the image data to.
+*   `callback` **[Function][3]?** called on completion with two arguments `(err, info)`.
     `info` contains the output image `format`, `size` (bytes), `width`, `height`,
     `channels` and `premultiplied` (indicating if premultiplication was used).
     When using a crop strategy also contains `cropOffsetLeft` and `cropOffsetTop`.
 
+### Examples
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+```javascript
+sharp(input)
+  .toFile('output.png', (err, info) => { ... });
+```
 
-Returns **[Promise](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Promise)&lt;[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)>** when no callback is provided
+```javascript
+sharp(input)
+  .toFile('output.png')
+  .then(info => { ... })
+  .catch(err => { ... });
+```
+
+*   Throws **[Error][4]** Invalid parameters
+
+Returns **[Promise][5]<[Object][6]>** when no callback is provided
 
 ## toBuffer
 
 Write output to a Buffer.
-JPEG, PNG, WebP, TIFF and RAW output are supported.
-By default, the format will match the input image, except GIF and SVG input which become PNG output.
+JPEG, PNG, WebP, AVIF, TIFF and raw pixel data output are supported.
+
+If no explicit format is set, the output format will match the input image, except GIF and SVG input which become PNG output.
+
+By default all metadata will be removed, which includes EXIF-based orientation.
+See [withMetadata][1] for control over this.
 
 `callback`, if present, gets three arguments `(err, data, info)` where:
 
--   `err` is an error, if any.
--   `data` is the output image data.
--   `info` contains the output image `format`, `size` (bytes), `width`, `height`,
-    `channels` and `premultiplied` (indicating if premultiplication was used).
-    When using a crop strategy also contains `cropOffsetLeft` and `cropOffsetTop`.
+*   `err` is an error, if any.
+*   `data` is the output image data.
+*   `info` contains the output image `format`, `size` (bytes), `width`, `height`,
+
+`channels` and `premultiplied` (indicating if premultiplication was used).
+When using a crop strategy also contains `cropOffsetLeft` and `cropOffsetTop`.
 
 A `Promise` is returned when `callback` is not provided.
 
-**Parameters**
+### Parameters
 
--   `options` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** 
-    -   `options.resolveWithObject` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)?** Resolve the Promise with an Object containing `data` and `info` properties instead of resolving only with `data`.
--   `callback` **[Function](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/function)?** 
+*   `options` **[Object][6]?** 
 
-Returns **[Promise](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Promise)&lt;[Buffer](https://nodejs.org/api/buffer.html)>** when no callback is provided
+    *   `options.resolveWithObject` **[boolean][7]?** Resolve the Promise with an Object containing `data` and `info` properties instead of resolving only with `data`.
+*   `callback` **[Function][3]?** 
+
+### Examples
+
+```javascript
+sharp(input)
+  .toBuffer((err, data, info) => { ... });
+```
+
+```javascript
+sharp(input)
+  .toBuffer()
+  .then(data => { ... })
+  .catch(err => { ... });
+```
+
+```javascript
+sharp(input)
+  .toBuffer({ resolveWithObject: true })
+  .then(({ data, info }) => { ... })
+  .catch(err => { ... });
+```
+
+```javascript
+const { data, info } = await sharp('my-image.jpg')
+  // output the raw pixels
+  .raw()
+  .toBuffer({ resolveWithObject: true });
+
+// create a more type safe way to work with the raw pixel data
+// this will not copy the data, instead it will change `data`s underlying ArrayBuffer
+// so `data` and `pixelArray` point to the same memory location
+const pixelArray = new Uint8ClampedArray(data.buffer);
+
+// When you are done changing the pixelArray, sharp takes the `pixelArray` as an input
+const { width, height, channels } = info;
+await sharp(pixelArray, { raw: { width, height, channels } })
+  .toFile('my-changed-image.jpg');
+```
+
+Returns **[Promise][5]<[Buffer][8]>** when no callback is provided
 
 ## withMetadata
 
 Include all metadata (EXIF, XMP, IPTC) from the input image in the output image.
-The default behaviour, when `withMetadata` is not used, is to strip all metadata and convert to the device-independent sRGB colour space.
-This will also convert to and add a web-friendly sRGB ICC profile.
+This will also convert to and add a web-friendly sRGB ICC profile unless a custom
+output profile is provided.
 
-**Parameters**
+The default behaviour, when `withMetadata` is not used, is to convert to the device-independent
+sRGB colour space and strip all metadata, including the removal of any ICC profile.
 
--   `withMetadata` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** 
-    -   `withMetadata.orientation` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** value between 1 and 8, used to update the EXIF `Orientation` tag.
+### Parameters
 
+*   `options` **[Object][6]?** 
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+    *   `options.orientation` **[number][9]?** value between 1 and 8, used to update the EXIF `Orientation` tag.
+    *   `options.icc` **[string][2]?** filesystem path to output ICC profile, defaults to sRGB.
+    *   `options.exif` **[Object][6]<[Object][6]>** Object keyed by IFD0, IFD1 etc. of key/value string pairs to write as EXIF data. (optional, default `{}`)
+    *   `options.density` **[number][9]?** Number of pixels per inch (DPI).
 
-Returns **Sharp** 
+### Examples
 
-## jpeg
+```javascript
+sharp('input.jpg')
+  .withMetadata()
+  .toFile('output-with-metadata.jpg')
+  .then(info => { ... });
+```
 
-Use these JPEG options for output image.
+```javascript
+// Set "IFD0-Copyright" in output EXIF metadata
+const data = await sharp(input)
+  .withMetadata({
+    exif: {
+      IFD0: {
+        Copyright: 'Wernham Hogg'
+      }
+    }
+  })
+  .toBuffer();
 
-**Parameters**
+ * @example
+// Set output metadata to 96 DPI
+const data = await sharp(input)
+  .withMetadata({ density: 96 })
+  .toBuffer();
+```
 
--   `options` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** output options
-    -   `options.quality` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** quality, integer 1-100 (optional, default `80`)
-    -   `options.progressive` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** use progressive (interlace) scan (optional, default `false`)
-    -   `options.chromaSubsampling` **[String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String)** set to '4:4:4' to prevent chroma subsampling when quality &lt;= 90 (optional, default `'4:2:0'`)
-    -   `options.trellisQuantisation` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** apply trellis quantisation, requires mozjpeg (optional, default `false`)
-    -   `options.overshootDeringing` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** apply overshoot deringing, requires mozjpeg (optional, default `false`)
-    -   `options.optimiseScans` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** optimise progressive scans, forces progressive, requires mozjpeg (optional, default `false`)
-    -   `options.optimizeScans` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** alternative spelling of optimiseScans (optional, default `false`)
-    -   `options.force` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** force JPEG output, otherwise attempt to use input format (optional, default `true`)
-
-
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid options
-
-Returns **Sharp** 
-
-## png
-
-Use these PNG options for output image.
-
-**Parameters**
-
--   `options` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** 
-    -   `options.progressive` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** use progressive (interlace) scan (optional, default `false`)
-    -   `options.compressionLevel` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** zlib compression level, 0-9 (optional, default `9`)
-    -   `options.adaptiveFiltering` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** use adaptive row filtering (optional, default `false`)
-    -   `options.force` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** force PNG output, otherwise attempt to use input format (optional, default `true`)
-
-
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid options
-
-Returns **Sharp** 
-
-## webp
-
-Use these WebP options for output image.
-
-**Parameters**
-
--   `options` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** output options
-    -   `options.quality` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** quality, integer 1-100 (optional, default `80`)
-    -   `options.alphaQuality` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** quality of alpha layer, integer 0-100 (optional, default `100`)
-    -   `options.lossless` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** use lossless compression mode (optional, default `false`)
-    -   `options.nearLossless` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** use near_lossless compression mode (optional, default `false`)
-    -   `options.force` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** force WebP output, otherwise attempt to use input format (optional, default `true`)
-
-
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid options
-
-Returns **Sharp** 
-
-## tiff
-
-Use these TIFF options for output image.
-
-**Parameters**
-
--   `options` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** output options
-    -   `options.quality` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** quality, integer 1-100 (optional, default `80`)
-    -   `options.force` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** force TIFF output, otherwise attempt to use input format (optional, default `true`)
-    -   `options.compression` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** compression options: lzw, deflate, jpeg (optional, default `'jpeg'`)
-    -   `options.predictor` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** compression predictor options: none, horizontal, float (optional, default `'horizontal'`)
-    -   `options.xres` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** horizontal resolution in pixels/mm (optional, default `1.0`)
-    -   `options.yres` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** vertical resolution in pixels/mm (optional, default `1.0`)
-    -   `options.squash` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** squash 8-bit images down to 1 bit (optional, default `false`)
-
-
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid options
-
-Returns **Sharp** 
-
-## raw
-
-Force output to be raw, uncompressed uint8 pixel data.
+*   Throws **[Error][4]** Invalid parameters
 
 Returns **Sharp** 
 
@@ -162,32 +163,370 @@ Returns **Sharp**
 
 Force output to a given format.
 
-**Parameters**
+### Parameters
 
--   `format` **([String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String) \| [Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object))** as a String or an Object with an 'id' attribute
--   `options` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)** output options
+*   `format` **([string][2] | [Object][6])** as a string or an Object with an 'id' attribute
+*   `options` **[Object][6]** output options
 
+### Examples
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** unsupported format or options
+```javascript
+// Convert any input to PNG output
+const data = await sharp(input)
+  .toFormat('png')
+  .toBuffer();
+```
+
+*   Throws **[Error][4]** unsupported format or options
 
 Returns **Sharp** 
 
+## jpeg
+
+Use these JPEG options for output image.
+
+### Parameters
+
+*   `options` **[Object][6]?** output options
+
+    *   `options.quality` **[number][9]** quality, integer 1-100 (optional, default `80`)
+    *   `options.progressive` **[boolean][7]** use progressive (interlace) scan (optional, default `false`)
+    *   `options.chromaSubsampling` **[string][2]** set to '4:4:4' to prevent chroma subsampling otherwise defaults to '4:2:0' chroma subsampling (optional, default `'4:2:0'`)
+    *   `options.optimiseCoding` **[boolean][7]** optimise Huffman coding tables (optional, default `true`)
+    *   `options.optimizeCoding` **[boolean][7]** alternative spelling of optimiseCoding (optional, default `true`)
+    *   `options.mozjpeg` **[boolean][7]** use mozjpeg defaults, equivalent to `{ trellisQuantisation: true, overshootDeringing: true, optimiseScans: true, quantisationTable: 3 }` (optional, default `false`)
+    *   `options.trellisQuantisation` **[boolean][7]** apply trellis quantisation (optional, default `false`)
+    *   `options.overshootDeringing` **[boolean][7]** apply overshoot deringing (optional, default `false`)
+    *   `options.optimiseScans` **[boolean][7]** optimise progressive scans, forces progressive (optional, default `false`)
+    *   `options.optimizeScans` **[boolean][7]** alternative spelling of optimiseScans (optional, default `false`)
+    *   `options.quantisationTable` **[number][9]** quantization table to use, integer 0-8 (optional, default `0`)
+    *   `options.quantizationTable` **[number][9]** alternative spelling of quantisationTable (optional, default `0`)
+    *   `options.force` **[boolean][7]** force JPEG output, otherwise attempt to use input format (optional, default `true`)
+
+### Examples
+
+```javascript
+// Convert any input to very high quality JPEG output
+const data = await sharp(input)
+  .jpeg({
+    quality: 100,
+    chromaSubsampling: '4:4:4'
+  })
+  .toBuffer();
+```
+
+```javascript
+// Use mozjpeg to reduce output JPEG file size (slower)
+const data = await sharp(input)
+  .jpeg({ mozjpeg: true })
+  .toBuffer();
+```
+
+*   Throws **[Error][4]** Invalid options
+
+Returns **Sharp** 
+
+## png
+
+Use these PNG options for output image.
+
+By default, PNG output is full colour at 8 or 16 bits per pixel.
+Indexed PNG input at 1, 2 or 4 bits per pixel is converted to 8 bits per pixel.
+Set `palette` to `true` for slower, indexed PNG output.
+
+### Parameters
+
+*   `options` **[Object][6]?** 
+
+    *   `options.progressive` **[boolean][7]** use progressive (interlace) scan (optional, default `false`)
+    *   `options.compressionLevel` **[number][9]** zlib compression level, 0 (fastest, largest) to 9 (slowest, smallest) (optional, default `6`)
+    *   `options.adaptiveFiltering` **[boolean][7]** use adaptive row filtering (optional, default `false`)
+    *   `options.palette` **[boolean][7]** quantise to a palette-based image with alpha transparency support (optional, default `false`)
+    *   `options.quality` **[number][9]** use the lowest number of colours needed to achieve given quality, sets `palette` to `true` (optional, default `100`)
+    *   `options.colours` **[number][9]** maximum number of palette entries, sets `palette` to `true` (optional, default `256`)
+    *   `options.colors` **[number][9]** alternative spelling of `options.colours`, sets `palette` to `true` (optional, default `256`)
+    *   `options.dither` **[number][9]** level of Floyd-Steinberg error diffusion, sets `palette` to `true` (optional, default `1.0`)
+    *   `options.force` **[boolean][7]** force PNG output, otherwise attempt to use input format (optional, default `true`)
+
+### Examples
+
+```javascript
+// Convert any input to full colour PNG output
+const data = await sharp(input)
+  .png()
+  .toBuffer();
+```
+
+```javascript
+// Convert any input to indexed PNG output (slower)
+const data = await sharp(input)
+  .png({ palette: true })
+  .toBuffer();
+```
+
+*   Throws **[Error][4]** Invalid options
+
+Returns **Sharp** 
+
+## webp
+
+Use these WebP options for output image.
+
+### Parameters
+
+*   `options` **[Object][6]?** output options
+
+    *   `options.quality` **[number][9]** quality, integer 1-100 (optional, default `80`)
+    *   `options.alphaQuality` **[number][9]** quality of alpha layer, integer 0-100 (optional, default `100`)
+    *   `options.lossless` **[boolean][7]** use lossless compression mode (optional, default `false`)
+    *   `options.nearLossless` **[boolean][7]** use near_lossless compression mode (optional, default `false`)
+    *   `options.smartSubsample` **[boolean][7]** use high quality chroma subsampling (optional, default `false`)
+    *   `options.reductionEffort` **[number][9]** level of CPU effort to reduce file size, integer 0-6 (optional, default `4`)
+    *   `options.pageHeight` **[number][9]?** page height for animated output
+    *   `options.loop` **[number][9]** number of animation iterations, use 0 for infinite animation (optional, default `0`)
+    *   `options.delay` **[Array][10]<[number][9]>?** list of delays between animation frames (in milliseconds)
+    *   `options.force` **[boolean][7]** force WebP output, otherwise attempt to use input format (optional, default `true`)
+
+### Examples
+
+```javascript
+// Convert any input to lossless WebP output
+const data = await sharp(input)
+  .webp({ lossless: true })
+  .toBuffer();
+```
+
+```javascript
+// Optimise the file size of an animated WebP
+const outputWebp = await sharp(inputWebp, { animated: true })
+  .webp({ reductionEffort: 6 })
+  .toBuffer();
+```
+
+*   Throws **[Error][4]** Invalid options
+
+Returns **Sharp** 
+
+## gif
+
+Use these GIF options for output image.
+
+Requires libvips compiled with support for ImageMagick or GraphicsMagick.
+The prebuilt binaries do not include this - see
+[installing a custom libvips][11].
+
+### Parameters
+
+*   `options` **[Object][6]?** output options
+
+    *   `options.pageHeight` **[number][9]?** page height for animated output
+    *   `options.loop` **[number][9]** number of animation iterations, use 0 for infinite animation (optional, default `0`)
+    *   `options.delay` **[Array][10]<[number][9]>?** list of delays between animation frames (in milliseconds)
+    *   `options.force` **[boolean][7]** force GIF output, otherwise attempt to use input format (optional, default `true`)
+
+<!---->
+
+*   Throws **[Error][4]** Invalid options
+
+Returns **Sharp** 
+
+## jp2
+
+Use these JP2 options for output image.
+
+Requires libvips compiled with support for OpenJPEG.
+The prebuilt binaries do not include this - see
+[installing a custom libvips][11].
+
+### Parameters
+
+*   `options` **[Object][6]?** output options
+
+    *   `options.quality` **[number][9]** quality, integer 1-100 (optional, default `80`)
+    *   `options.lossless` **[boolean][7]** use lossless compression mode (optional, default `false`)
+    *   `options.tileWidth` **[number][9]** horizontal tile size (optional, default `512`)
+    *   `options.tileHeight` **[number][9]** vertical tile size (optional, default `512`)
+    *   `options.chromaSubsampling` **[string][2]** set to '4:2:0' to use chroma subsampling (optional, default `'4:4:4'`)
+
+### Examples
+
+```javascript
+// Convert any input to lossless JP2 output
+const data = await sharp(input)
+  .jp2({ lossless: true })
+  .toBuffer();
+```
+
+```javascript
+// Convert any input to very high quality JP2 output
+const data = await sharp(input)
+  .jp2({
+    quality: 100,
+    chromaSubsampling: '4:4:4'
+  })
+  .toBuffer();
+```
+
+*   Throws **[Error][4]** Invalid options
+
+Returns **Sharp** 
+
+**Meta**
+
+*   **since**: 0.29.1
+
+## tiff
+
+Use these TIFF options for output image.
+
+The `density` can be set in pixels/inch via [withMetadata][1] instead of providing `xres` and `yres` in pixels/mm.
+
+### Parameters
+
+*   `options` **[Object][6]?** output options
+
+    *   `options.quality` **[number][9]** quality, integer 1-100 (optional, default `80`)
+    *   `options.force` **[boolean][7]** force TIFF output, otherwise attempt to use input format (optional, default `true`)
+    *   `options.compression` **[string][2]** compression options: lzw, deflate, jpeg, ccittfax4 (optional, default `'jpeg'`)
+    *   `options.predictor` **[string][2]** compression predictor options: none, horizontal, float (optional, default `'horizontal'`)
+    *   `options.pyramid` **[boolean][7]** write an image pyramid (optional, default `false`)
+    *   `options.tile` **[boolean][7]** write a tiled tiff (optional, default `false`)
+    *   `options.tileWidth` **[number][9]** horizontal tile size (optional, default `256`)
+    *   `options.tileHeight` **[number][9]** vertical tile size (optional, default `256`)
+    *   `options.xres` **[number][9]** horizontal resolution in pixels/mm (optional, default `1.0`)
+    *   `options.yres` **[number][9]** vertical resolution in pixels/mm (optional, default `1.0`)
+    *   `options.bitdepth` **[number][9]** reduce bitdepth to 1, 2 or 4 bit (optional, default `8`)
+
+### Examples
+
+```javascript
+// Convert SVG input to LZW-compressed, 1 bit per pixel TIFF output
+sharp('input.svg')
+  .tiff({
+    compression: 'lzw',
+    bitdepth: 1
+  })
+  .toFile('1-bpp-output.tiff')
+  .then(info => { ... });
+```
+
+*   Throws **[Error][4]** Invalid options
+
+Returns **Sharp** 
+
+## avif
+
+Use these AVIF options for output image.
+
+Whilst it is possible to create AVIF images smaller than 16x16 pixels,
+most web browsers do not display these properly.
+
+AVIF image sequences are not supported.
+
+### Parameters
+
+*   `options` **[Object][6]?** output options
+
+    *   `options.quality` **[number][9]** quality, integer 1-100 (optional, default `50`)
+    *   `options.lossless` **[boolean][7]** use lossless compression (optional, default `false`)
+    *   `options.speed` **[number][9]** CPU effort vs file size, 0 (slowest/smallest) to 9 (fastest/largest) (optional, default `5`)
+    *   `options.chromaSubsampling` **[string][2]** set to '4:2:0' to use chroma subsampling (optional, default `'4:4:4'`)
+
+<!---->
+
+*   Throws **[Error][4]** Invalid options
+
+Returns **Sharp** 
+
+**Meta**
+
+*   **since**: 0.27.0
+
+## heif
+
+Use these HEIF options for output image.
+
+Support for patent-encumbered HEIC images requires the use of a
+globally-installed libvips compiled with support for libheif, libde265 and x265.
+
+### Parameters
+
+*   `options` **[Object][6]?** output options
+
+    *   `options.quality` **[number][9]** quality, integer 1-100 (optional, default `50`)
+    *   `options.compression` **[string][2]** compression format: av1, hevc (optional, default `'av1'`)
+    *   `options.lossless` **[boolean][7]** use lossless compression (optional, default `false`)
+    *   `options.speed` **[number][9]** CPU effort vs file size, 0 (slowest/smallest) to 9 (fastest/largest) (optional, default `5`)
+    *   `options.chromaSubsampling` **[string][2]** set to '4:2:0' to use chroma subsampling (optional, default `'4:4:4'`)
+
+<!---->
+
+*   Throws **[Error][4]** Invalid options
+
+Returns **Sharp** 
+
+**Meta**
+
+*   **since**: 0.23.0
+
+## raw
+
+Force output to be raw, uncompressed pixel data.
+Pixel ordering is left-to-right, top-to-bottom, without padding.
+Channel ordering will be RGB or RGBA for non-greyscale colourspaces.
+
+### Parameters
+
+*   `options` **[Object][6]?** output options
+
+    *   `options.depth` **[string][2]** bit depth, one of: char, uchar (default), short, ushort, int, uint, float, complex, double, dpcomplex (optional, default `'uchar'`)
+
+### Examples
+
+```javascript
+// Extract raw, unsigned 8-bit RGB pixel data from JPEG input
+const { data, info } = await sharp('input.jpg')
+  .raw()
+  .toBuffer({ resolveWithObject: true });
+```
+
+```javascript
+// Extract alpha channel as raw, unsigned 16-bit pixel data from PNG input
+const data = await sharp('input.png')
+  .ensureAlpha()
+  .extractChannel(3)
+  .toColourspace('b-w')
+  .raw({ depth: 'ushort' })
+  .toBuffer();
+```
+
+*   Throws **[Error][4]** Invalid options
+
 ## tile
 
 Use tile-based deep zoom (image pyramid) output.
 Set the format and options for tile images via the `toFormat`, `jpeg`, `png` or `webp` functions.
 Use a `.zip` or `.szi` file extension with `toFile` to write to a compressed archive file format.
 
-**Parameters**
+Warning: multiple sharp instances concurrently producing tile output can expose a possible race condition in some versions of libgsf.
 
--   `tile` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** 
-    -   `tile.size` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** tile size in pixels, a value between 1 and 8192. (optional, default `256`)
-    -   `tile.overlap` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** tile overlap in pixels, a value between 0 and 8192. (optional, default `0`)
-    -   `tile.angle` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** tile angle of rotation, must be a multiple of 90. (optional, default `0`)
-    -   `tile.container` **[String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String)** tile container, with value `fs` (filesystem) or `zip` (compressed file). (optional, default `'fs'`)
-    -   `tile.layout` **[String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String)** filesystem layout, possible values are `dz`, `zoomify` or `google`. (optional, default `'dz'`)
+### Parameters
 
-**Examples**
+*   `options` **[Object][6]?** 
+
+    *   `options.size` **[number][9]** tile size in pixels, a value between 1 and 8192. (optional, default `256`)
+    *   `options.overlap` **[number][9]** tile overlap in pixels, a value between 0 and 8192. (optional, default `0`)
+    *   `options.angle` **[number][9]** tile angle of rotation, must be a multiple of 90. (optional, default `0`)
+    *   `options.background` **([string][2] | [Object][6])** background colour, parsed by the [color][12] module, defaults to white without transparency. (optional, default `{r:255,g:255,b:255,alpha:1}`)
+    *   `options.depth` **[string][2]?** how deep to make the pyramid, possible values are `onepixel`, `onetile` or `one`, default based on layout.
+    *   `options.skipBlanks` **[number][9]** threshold to skip tile generation, a value 0 - 255 for 8-bit images or 0 - 65535 for 16-bit images (optional, default `-1`)
+    *   `options.container` **[string][2]** tile container, with value `fs` (filesystem) or `zip` (compressed file). (optional, default `'fs'`)
+    *   `options.layout` **[string][2]** filesystem layout, possible values are `dz`, `iiif`, `zoomify` or `google`. (optional, default `'dz'`)
+    *   `options.centre` **[boolean][7]** centre image in tile. (optional, default `false`)
+    *   `options.center` **[boolean][7]** alternative spelling of centre. (optional, default `false`)
+    *   `options.id` **[string][2]** when `layout` is `iiif`, sets the `@id` attribute of `info.json` (optional, default `'https://example.com/iiif'`)
+
+### Examples
 
 ```javascript
 sharp('input.tiff')
@@ -201,6 +540,50 @@ sharp('input.tiff')
   });
 ```
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
+*   Throws **[Error][4]** Invalid parameters
 
 Returns **Sharp** 
+
+## timeout
+
+Set a timeout for processing, in seconds.
+Use a value of zero to continue processing indefinitely, the default behaviour.
+
+The clock starts when libvips opens an input image for processing.
+Time spent waiting for a libuv thread to become available is not included.
+
+### Parameters
+
+*   `options` **[Object][6]** 
+
+    *   `options.seconds` **[number][9]** Number of seconds after which processing will be stopped
+
+Returns **Sharp** 
+
+**Meta**
+
+*   **since**: 0.29.2
+
+[1]: #withmetadata
+
+[2]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String
+
+[3]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/function
+
+[4]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error
+
+[5]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Promise
+
+[6]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object
+
+[7]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean
+
+[8]: https://nodejs.org/api/buffer.html
+
+[9]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number
+
+[10]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Array
+
+[11]: https://sharp.pixelplumbing.com/install#custom-libvips
+
+[12]: https://www.npmjs.org/package/color

docs/api-resize.md

@@ -1,174 +1,262 @@
 <!-- Generated by documentation.js. Update this documentation by updating the source code. -->
 
-### Table of Contents
-
--   [resize](#resize)
--   [crop](#crop)
--   [embed](#embed)
--   [max](#max)
--   [min](#min)
--   [ignoreAspectRatio](#ignoreaspectratio)
--   [withoutEnlargement](#withoutenlargement)
-
 ## resize
 
-Resize image to `width` x `height`.
-By default, the resized image is centre cropped to the exact size specified.
+Resize image to `width`, `height` or `width x height`.
 
-Possible kernels are:
+When both a `width` and `height` are provided, the possible methods by which the image should **fit** these are:
 
--   `nearest`: Use [nearest neighbour interpolation](http://en.wikipedia.org/wiki/Nearest-neighbor_interpolation).
--   `cubic`: Use a [Catmull-Rom spline](https://en.wikipedia.org/wiki/Centripetal_Catmull%E2%80%93Rom_spline).
--   `lanczos2`: Use a [Lanczos kernel](https://en.wikipedia.org/wiki/Lanczos_resampling#Lanczos_kernel) with `a=2`.
--   `lanczos3`: Use a Lanczos kernel with `a=3` (the default).
+*   `cover`: (default) Preserving aspect ratio, ensure the image covers both provided dimensions by cropping/clipping to fit.
+*   `contain`: Preserving aspect ratio, contain within both provided dimensions using "letterboxing" where necessary.
+*   `fill`: Ignore the aspect ratio of the input and stretch to both provided dimensions.
+*   `inside`: Preserving aspect ratio, resize the image to be as large as possible while ensuring its dimensions are less than or equal to both those specified.
+*   `outside`: Preserving aspect ratio, resize the image to be as small as possible while ensuring its dimensions are greater than or equal to both those specified.
 
-**Parameters**
+Some of these values are based on the [object-fit][1] CSS property.
 
--   `width` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** pixels wide the resultant image should be. Use `null` or `undefined` to auto-scale the width to match the height.
--   `height` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** pixels high the resultant image should be. Use `null` or `undefined` to auto-scale the height to match the width.
--   `options` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** 
-    -   `options.kernel` **[String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String)** the kernel to use for image reduction. (optional, default `'lanczos3'`)
-    -   `options.fastShrinkOnLoad` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** take greater advantage of the JPEG and WebP shrink-on-load feature, which can lead to a slight moiré pattern on some images. (optional, default `true`)
+When using a `fit` of `cover` or `contain`, the default **position** is `centre`. Other options are:
 
-**Examples**
+*   `sharp.position`: `top`, `right top`, `right`, `right bottom`, `bottom`, `left bottom`, `left`, `left top`.
+*   `sharp.gravity`: `north`, `northeast`, `east`, `southeast`, `south`, `southwest`, `west`, `northwest`, `center` or `centre`.
+*   `sharp.strategy`: `cover` only, dynamically crop using either the `entropy` or `attention` strategy.
 
-```javascript
-sharp(inputBuffer)
-  .resize(200, 300, {
-    kernel: sharp.kernel.nearest
-  })
-  .background('white')
-  .embed()
-  .toFile('output.tiff')
-  .then(function() {
-    // output.tiff is a 200 pixels wide and 300 pixels high image
-    // containing a nearest-neighbour scaled version, embedded on a white canvas,
-    // of the image data in inputBuffer
-  });
-```
-
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
-
-Returns **Sharp** 
-
-## crop
-
-Crop the resized image to the exact size specified, the default behaviour.
-
-Possible attributes of the optional `sharp.gravity` are `north`, `northeast`, `east`, `southeast`, `south`,
-`southwest`, `west`, `northwest`, `center` and `centre`.
+Some of these values are based on the [object-position][2] CSS property.
 
 The experimental strategy-based approach resizes so one dimension is at its target length
 then repeatedly ranks edge regions, discarding the edge with the lowest score based on the selected strategy.
 
--   `entropy`: focus on the region with the highest [Shannon entropy](https://en.wikipedia.org/wiki/Entropy_%28information_theory%29).
--   `attention`: focus on the region with the highest luminance frequency, colour saturation and presence of skin tones.
+*   `entropy`: focus on the region with the highest [Shannon entropy][3].
+*   `attention`: focus on the region with the highest luminance frequency, colour saturation and presence of skin tones.
 
-**Parameters**
+Possible interpolation kernels are:
 
--   `crop` **[String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String)** A member of `sharp.gravity` to crop to an edge/corner or `sharp.strategy` to crop dynamically. (optional, default `'centre'`)
+*   `nearest`: Use [nearest neighbour interpolation][4].
+*   `cubic`: Use a [Catmull-Rom spline][5].
+*   `mitchell`: Use a [Mitchell-Netravali spline][6].
+*   `lanczos2`: Use a [Lanczos kernel][7] with `a=2`.
+*   `lanczos3`: Use a Lanczos kernel with `a=3` (the default).
 
-**Examples**
+### Parameters
+
+*   `width` **[number][8]?** pixels wide the resultant image should be. Use `null` or `undefined` to auto-scale the width to match the height.
+*   `height` **[number][8]?** pixels high the resultant image should be. Use `null` or `undefined` to auto-scale the height to match the width.
+*   `options` **[Object][9]?** 
+
+    *   `options.width` **[String][10]?** alternative means of specifying `width`. If both are present this take priority.
+    *   `options.height` **[String][10]?** alternative means of specifying `height`. If both are present this take priority.
+    *   `options.fit` **[String][10]** how the image should be resized to fit both provided dimensions, one of `cover`, `contain`, `fill`, `inside` or `outside`. (optional, default `'cover'`)
+    *   `options.position` **[String][10]** position, gravity or strategy to use when `fit` is `cover` or `contain`. (optional, default `'centre'`)
+    *   `options.background` **([String][10] | [Object][9])** background colour when using a `fit` of `contain`, parsed by the [color][11] module, defaults to black without transparency. (optional, default `{r:0,g:0,b:0,alpha:1}`)
+    *   `options.kernel` **[String][10]** the kernel to use for image reduction. (optional, default `'lanczos3'`)
+    *   `options.withoutEnlargement` **[Boolean][12]** do not enlarge if the width *or* height are already less than the specified dimensions, equivalent to GraphicsMagick's `>` geometry option. (optional, default `false`)
+    *   `options.fastShrinkOnLoad` **[Boolean][12]** take greater advantage of the JPEG and WebP shrink-on-load feature, which can lead to a slight moiré pattern on some images. (optional, default `true`)
+
+### Examples
+
+```javascript
+sharp(input)
+  .resize({ width: 100 })
+  .toBuffer()
+  .then(data => {
+    // 100 pixels wide, auto-scaled height
+  });
+```
+
+```javascript
+sharp(input)
+  .resize({ height: 100 })
+  .toBuffer()
+  .then(data => {
+    // 100 pixels high, auto-scaled width
+  });
+```
+
+```javascript
+sharp(input)
+  .resize(200, 300, {
+    kernel: sharp.kernel.nearest,
+    fit: 'contain',
+    position: 'right top',
+    background: { r: 255, g: 255, b: 255, alpha: 0.5 }
+  })
+  .toFile('output.png')
+  .then(() => {
+    // output.png is a 200 pixels wide and 300 pixels high image
+    // containing a nearest-neighbour scaled version
+    // contained within the north-east corner of a semi-transparent white canvas
+  });
+```
 
 ```javascript
 const transformer = sharp()
-  .resize(200, 200)
-  .crop(sharp.strategy.entropy)
-  .on('error', function(err) {
-    console.log(err);
+  .resize({
+    width: 200,
+    height: 200,
+    fit: sharp.fit.cover,
+    position: sharp.strategy.entropy
   });
 // Read image data from readableStream
 // Write 200px square auto-cropped image data to writableStream
-readableStream.pipe(transformer).pipe(writableStream);
+readableStream
+  .pipe(transformer)
+  .pipe(writableStream);
 ```
 
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
-
-Returns **Sharp** 
-
-## embed
-
-Preserving aspect ratio, resize the image to the maximum `width` or `height` specified
-then embed on a background of the exact `width` and `height` specified.
-
-If the background contains an alpha value then WebP and PNG format output images will
-contain an alpha channel, even when the input image does not.
-
-**Parameters**
-
--   `embed` **[String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String)** A member of `sharp.gravity` to embed to an edge/corner. (optional, default `'centre'`)
-
-**Examples**
-
 ```javascript
-sharp('input.gif')
-  .resize(200, 300)
-  .background({r: 0, g: 0, b: 0, alpha: 0})
-  .embed()
-  .toFormat(sharp.format.webp)
-  .toBuffer(function(err, outputBuffer) {
-    if (err) {
-      throw err;
-    }
-    // outputBuffer contains WebP image data of a 200 pixels wide and 300 pixels high
-    // containing a scaled version, embedded on a transparent canvas, of input.gif
-  });
-```
-
--   Throws **[Error](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error)** Invalid parameters
-
-Returns **Sharp** 
-
-## max
-
-Preserving aspect ratio, resize the image to be as large as possible
-while ensuring its dimensions are less than or equal to the `width` and `height` specified.
-
-Both `width` and `height` must be provided via `resize` otherwise the behaviour will default to `crop`.
-
-**Examples**
-
-```javascript
-sharp(inputBuffer)
-  .resize(200, 200)
-  .max()
+sharp(input)
+  .resize(200, 200, {
+    fit: sharp.fit.inside,
+    withoutEnlargement: true
+  })
   .toFormat('jpeg')
   .toBuffer()
   .then(function(outputBuffer) {
-    // outputBuffer contains JPEG image data no wider than 200 pixels and no higher
-    // than 200 pixels regardless of the inputBuffer image dimensions
+    // outputBuffer contains JPEG image data
+    // no wider and no higher than 200 pixels
+    // and no larger than the input image
   });
 ```
 
-Returns **Sharp** 
+```javascript
+const scaleByHalf = await sharp(input)
+  .metadata()
+  .then(({ width }) => sharp(input)
+    .resize(Math.round(width * 0.5))
+    .toBuffer()
+  );
+```
 
-## min
-
-Preserving aspect ratio, resize the image to be as small as possible
-while ensuring its dimensions are greater than or equal to the `width` and `height` specified.
-
-Both `width` and `height` must be provided via `resize` otherwise the behaviour will default to `crop`.
+*   Throws **[Error][13]** Invalid parameters
 
 Returns **Sharp** 
 
-## ignoreAspectRatio
+## extend
 
-Ignoring the aspect ratio of the input, stretch the image to
-the exact `width` and/or `height` provided via `resize`.
+Extends/pads the edges of the image with the provided background colour.
+This operation will always occur after resizing and extraction, if any.
+
+### Parameters
+
+*   `extend` **([number][8] | [Object][9])** single pixel count to add to all edges or an Object with per-edge counts
+
+    *   `extend.top` **[number][8]**  (optional, default `0`)
+    *   `extend.left` **[number][8]**  (optional, default `0`)
+    *   `extend.bottom` **[number][8]**  (optional, default `0`)
+    *   `extend.right` **[number][8]**  (optional, default `0`)
+    *   `extend.background` **([String][10] | [Object][9])** background colour, parsed by the [color][11] module, defaults to black without transparency. (optional, default `{r:0,g:0,b:0,alpha:1}`)
+
+### Examples
+
+```javascript
+// Resize to 140 pixels wide, then add 10 transparent pixels
+// to the top, left and right edges and 20 to the bottom edge
+sharp(input)
+  .resize(140)
+  .extend({
+    top: 10,
+    bottom: 20,
+    left: 10,
+    right: 10,
+    background: { r: 0, g: 0, b: 0, alpha: 0 }
+  })
+  ...
+```
+
+```javascript
+// Add a row of 10 red pixels to the bottom
+sharp(input)
+  .extend({
+    bottom: 10,
+    background: 'red'
+  })
+  ...
+```
+
+*   Throws **[Error][13]** Invalid parameters
 
 Returns **Sharp** 
 
-## withoutEnlargement
+## extract
 
-Do not enlarge the output image if the input image width _or_ height are already less than the required dimensions.
-This is equivalent to GraphicsMagick's `>` geometry option:
-"_change the dimensions of the image only if its width or height exceeds the geometry specification_".
-Use with `max()` to preserve the image's aspect ratio.
+Extract/crop a region of the image.
 
-The default behaviour _before_ function call is `false`, meaning the image will be enlarged.
+*   Use `extract` before `resize` for pre-resize extraction.
+*   Use `extract` after `resize` for post-resize extraction.
+*   Use `extract` before and after for both.
 
-**Parameters**
+### Parameters
 
--   `withoutEnlargement` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)**  (optional, default `true`)
+*   `options` **[Object][9]** describes the region to extract using integral pixel values
+
+    *   `options.left` **[number][8]** zero-indexed offset from left edge
+    *   `options.top` **[number][8]** zero-indexed offset from top edge
+    *   `options.width` **[number][8]** width of region to extract
+    *   `options.height` **[number][8]** height of region to extract
+
+### Examples
+
+```javascript
+sharp(input)
+  .extract({ left: left, top: top, width: width, height: height })
+  .toFile(output, function(err) {
+    // Extract a region of the input image, saving in the same format.
+  });
+```
+
+```javascript
+sharp(input)
+  .extract({ left: leftOffsetPre, top: topOffsetPre, width: widthPre, height: heightPre })
+  .resize(width, height)
+  .extract({ left: leftOffsetPost, top: topOffsetPost, width: widthPost, height: heightPost })
+  .toFile(output, function(err) {
+    // Extract a region, resize, then extract from the resized image
+  });
+```
+
+*   Throws **[Error][13]** Invalid parameters
 
 Returns **Sharp** 
+
+## trim
+
+Trim "boring" pixels from all edges that contain values similar to the top-left pixel.
+Images consisting entirely of a single colour will calculate "boring" using the alpha channel, if any.
+
+The `info` response Object, obtained from callback of `.toFile()` or `.toBuffer()`,
+will contain `trimOffsetLeft` and `trimOffsetTop` properties.
+
+### Parameters
+
+*   `threshold` **[number][8]** the allowed difference from the top-left pixel, a number greater than zero. (optional, default `10`)
+
+<!---->
+
+*   Throws **[Error][13]** Invalid parameters
+
+Returns **Sharp** 
+
+[1]: https://developer.mozilla.org/en-US/docs/Web/CSS/object-fit
+
+[2]: https://developer.mozilla.org/en-US/docs/Web/CSS/object-position
+
+[3]: https://en.wikipedia.org/wiki/Entropy_%28information_theory%29
+
+[4]: http://en.wikipedia.org/wiki/Nearest-neighbor_interpolation
+
+[5]: https://en.wikipedia.org/wiki/Centripetal_Catmull%E2%80%93Rom_spline
+
+[6]: https://www.cs.utexas.edu/~fussell/courses/cs384g-fall2013/lectures/mitchell/Mitchell.pdf
+
+[7]: https://en.wikipedia.org/wiki/Lanczos_resampling#Lanczos_kernel
+
+[8]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number
+
+[9]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object
+
+[10]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String
+
+[11]: https://www.npmjs.org/package/color
+
+[12]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean
+
+[13]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error

docs/api-utility.md

@@ -1,27 +1,73 @@
 <!-- Generated by documentation.js. Update this documentation by updating the source code. -->
 
-### Table of Contents
+## format
 
--   [cache](#cache)
--   [concurrency](#concurrency)
--   [counters](#counters)
--   [simd](#simd)
+An Object containing nested boolean values representing the available input and output formats/methods.
+
+### Examples
+
+```javascript
+console.log(sharp.format);
+```
+
+Returns **[Object][1]** 
+
+## interpolators
+
+An Object containing the available interpolators and their proper values
+
+Type: [string][2]
+
+### nearest
+
+[Nearest neighbour interpolation][3]. Suitable for image enlargement only.
+
+### bilinear
+
+[Bilinear interpolation][4]. Faster than bicubic but with less smooth results.
+
+### bicubic
+
+[Bicubic interpolation][5] (the default).
+
+### locallyBoundedBicubic
+
+[LBB interpolation][6]. Prevents some "[acutance][7]" but typically reduces performance by a factor of 2.
+
+### nohalo
+
+[Nohalo interpolation][8]. Prevents acutance but typically reduces performance by a factor of 3.
+
+### vertexSplitQuadraticBasisSpline
+
+[VSQBS interpolation][9]. Prevents "staircasing" when enlarging.
+
+## versions
+
+An Object containing the version numbers of libvips and its dependencies.
+
+### Examples
+
+```javascript
+console.log(sharp.versions);
+```
 
 ## cache
 
-Gets or, when options are provided, sets the limits of _libvips'_ operation cache.
+Gets or, when options are provided, sets the limits of *libvips'* operation cache.
 Existing entries in the cache will be trimmed after any change in limits.
 This method always returns cache statistics,
 useful for determining how much working memory is required for a particular task.
 
-**Parameters**
+### Parameters
 
--   `options` **([Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object) \| [Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean))** Object with the following attributes, or Boolean where true uses default cache settings and false removes all caching (optional, default `true`)
-    -   `options.memory` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** is the maximum memory in MB to use for this cache (optional, default `50`)
-    -   `options.files` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** is the maximum number of files to hold open (optional, default `20`)
-    -   `options.items` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** is the maximum number of operations to cache (optional, default `100`)
+*   `options` **([Object][1] | [boolean][10])** Object with the following attributes, or boolean where true uses default cache settings and false removes all caching (optional, default `true`)
 
-**Examples**
+    *   `options.memory` **[number][11]** is the maximum memory in MB to use for this cache (optional, default `50`)
+    *   `options.files` **[number][11]** is the maximum number of files to hold open (optional, default `20`)
+    *   `options.items` **[number][11]** is the maximum number of operations to cache (optional, default `100`)
+
+### Examples
 
 ```javascript
 const stats = sharp.cache();
@@ -33,25 +79,29 @@ sharp.cache( { files: 0 } );
 sharp.cache(false);
 ```
 
-Returns **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)** 
+Returns **[Object][1]** 
 
 ## concurrency
 
 Gets or, when a concurrency is provided, sets
-the number of threads _libvips'_ should create to process each image.
-The default value is the number of CPU cores.
-A value of `0` will reset to this default.
+the number of threads *libvips'* should create to process each image.
+
+The default value is the number of CPU cores,
+except when using glibc-based Linux without jemalloc,
+where the default is `1` to help reduce memory fragmentation.
+
+A value of `0` will reset this to the number of CPU cores.
 
 The maximum number of images that can be processed in parallel
 is limited by libuv's `UV_THREADPOOL_SIZE` environment variable.
 
 This method always returns the current concurrency.
 
-**Parameters**
+### Parameters
 
--   `concurrency` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)?** 
+*   `concurrency` **[number][11]?** 
 
-**Examples**
+### Examples
 
 ```javascript
 const threads = sharp.concurrency(); // 4
@@ -59,22 +109,37 @@ sharp.concurrency(2); // 2
 sharp.concurrency(0); // 4
 ```
 
-Returns **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** concurrency
+Returns **[number][11]** concurrency
+
+## queue
+
+An EventEmitter that emits a `change` event when a task is either:
+
+*   queued, waiting for *libuv* to provide a worker thread
+*   complete
+
+### Examples
+
+```javascript
+sharp.queue.on('change', function(queueLength) {
+  console.log('Queue contains ' + queueLength + ' task(s)');
+});
+```
 
 ## counters
 
 Provides access to internal task counters.
 
--   queue is the number of tasks this module has queued waiting for _libuv_ to provide a worker thread from its pool.
--   process is the number of resize tasks currently being processed.
+*   queue is the number of tasks this module has queued waiting for *libuv* to provide a worker thread from its pool.
+*   process is the number of resize tasks currently being processed.
 
-**Examples**
+### Examples
 
 ```javascript
 const counters = sharp.counters(); // { queue: 2, process: 4 }
 ```
 
-Returns **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)** 
+Returns **[Object][1]** 
 
 ## simd
 
@@ -84,23 +149,42 @@ Requires libvips to have been compiled with liborc support.
 Improves the performance of `resize`, `blur` and `sharpen` operations
 by taking advantage of the SIMD vector unit of the CPU, e.g. Intel SSE and ARM NEON.
 
-This feature is currently off by default but future versions may reverse this.
-Versions of liborc prior to 0.4.25 are known to segfault under heavy load.
+### Parameters
 
-**Parameters**
+*   `simd` **[boolean][10]**  (optional, default `true`)
 
--   `simd` **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)**  (optional, default `false`)
-
-**Examples**
+### Examples
 
 ```javascript
 const simd = sharp.simd();
-// simd is `true` if SIMD is currently enabled
+// simd is `true` if the runtime use of liborc is currently enabled
 ```
 
 ```javascript
-const simd = sharp.simd(true);
-// attempts to enable the use of SIMD, returning true if available
+const simd = sharp.simd(false);
+// prevent libvips from using liborc at runtime
 ```
 
-Returns **[Boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** 
+Returns **[boolean][10]** 
+
+[1]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object
+
+[2]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String
+
+[3]: http://en.wikipedia.org/wiki/Nearest-neighbor_interpolation
+
+[4]: http://en.wikipedia.org/wiki/Bilinear_interpolation
+
+[5]: http://en.wikipedia.org/wiki/Bicubic_interpolation
+
+[6]: https://github.com/jcupitt/libvips/blob/master/libvips/resample/lbb.cpp#L100
+
+[7]: http://en.wikipedia.org/wiki/Acutance
+
+[8]: http://eprints.soton.ac.uk/268086/
+
+[9]: https://github.com/jcupitt/libvips/blob/master/libvips/resample/vsqbs.cpp#L48
+
+[10]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean
+
+[11]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number

docs/build.js

@@ -0,0 +1,25 @@
+'use strict';
+
+const fs = require('fs').promises;
+const path = require('path');
+const documentation = require('documentation');
+
+[
+  'constructor',
+  'input',
+  'resize',
+  'composite',
+  'operation',
+  'colour',
+  'channel',
+  'output',
+  'utility'
+].forEach(async (m) => {
+  const input = path.join('lib', `${m}.js`);
+  const output = path.join('docs', `api-${m}.md`);
+
+  const ast = await documentation.build(input, { shallow: true });
+  const markdown = await documentation.formats.md(ast, { markdownToc: false });
+
+  await fs.writeFile(output, markdown);
+});

docs/firebase.json

@@ -0,0 +1,116 @@
+{
+  "hosting": {
+    "site": "pixelplumbing-sharp",
+    "public": ".",
+    "ignore": [
+      ".*",
+      "build.js",
+      "firebase.json",
+      "image/**",
+      "search-index/**"
+    ],
+    "headers": [
+      {
+        "source": "**",
+        "headers": [
+          { "key": "Cache-Control", "value": "max-age=86400" },
+          { "key": "X-Content-Type-Options", "value": "nosniff" },
+          { "key": "X-Frame-Options", "value": "SAMEORIGIN" }
+        ]
+      }
+    ],
+    "redirects": [
+      {
+        "source": "**/install/**",
+        "destination": "/install",
+        "type": 301
+      },
+      {
+        "source": "/page/install",
+        "destination": "/install",
+        "type": 301
+      },
+      {
+        "source": "**/api-constructor/**",
+        "destination": "/api-constructor",
+        "type": 301
+      },
+      {
+        "source": "**/api-input/**",
+        "destination": "/api-input",
+        "type": 301
+      },
+      {
+        "source": "**/api-output/**",
+        "destination": "/api-output",
+        "type": 301
+      },
+      {
+        "source": "**/api-resize/**",
+        "destination": "/api-resize",
+        "type": 301
+      },
+      {
+        "source": "**/api-compsite/**",
+        "destination": "/api-compsite",
+        "type": 301
+      },
+      {
+        "source": "**/api-operation/**",
+        "destination": "/api-operation",
+        "type": 301
+      },
+      {
+        "source": "**/api-colour/**",
+        "destination": "/api-colour",
+        "type": 301
+      },
+      {
+        "source": "**/api-channel/**",
+        "destination": "/api-channel",
+        "type": 301
+      },
+      {
+        "source": "**/api-utility/**",
+        "destination": "/api-utility",
+        "type": 301
+      },
+      {
+        "source": "/page/api",
+        "destination": "/api-constructor",
+        "type": 301
+      },
+      {
+        "source": "**/performance/**",
+        "destination": "/performance",
+        "type": 301
+      },
+      {
+        "source": "/page/performance",
+        "destination": "/performance",
+        "type": 301
+      },
+      {
+        "source": "**/changelog/**",
+        "destination": "/changelog",
+        "type": 301
+      },
+      {
+        "source": "/page/changelog",
+        "destination": "/changelog",
+        "type": 301
+      },
+      {
+        "source": "/en/**",
+        "destination": "/",
+        "type": 301
+      }
+    ],
+    "rewrites": [
+      {
+        "source": "**",
+        "destination": "/index.html"
+      }
+    ]
+  }
+}

docs/humans.txt

@@ -0,0 +1,229 @@
+/* THANKS */
+
+Name: John Cupitt
+GitHub: https://github.com/jcupitt
+
+Name: Pierre Inglebert
+GitHub: https://github.com/pierreinglebert
+
+Name: Jonathan Ong
+GitHub: https://github.com/jonathanong
+
+Name: Chanon Sajjamanochai
+GitHub: https://github.com/chanon
+
+Name: Juliano Julio
+GitHub: https://github.com/julianojulio
+
+Name: Daniel Gasienica
+GitHub: https://github.com/gasi
+
+Name: Julian Walker
+GitHub: https://github.com/julianwa
+
+Name: Amit Pitaru
+GitHub: https://github.com/apitaru
+
+Name: Brandon Aaron
+GitHub: https://github.com/brandonaaron
+
+Name: Andreas Lind
+GitHub: https://github.com/papandreouGitHub:
+
+Name: Maurus Cuelenaere
+GitHub: https://github.com/mcuelenaere
+
+Name: Linus Unnebäck
+GitHub: https://github.com/LinusU
+
+Name: Victor Mateevitsi
+GitHub: https://github.com/mvictoras
+
+Name: Alaric Holloway
+GitHub: https://github.com/skedastik
+
+Name: Bernhard K. Weisshuhn
+GitHub: https://github.com/bkw
+
+Name: David A. Carley
+GitHub: https://github.com/dacarley
+
+Name: John Tobin
+GitHub: https://github.com/jtobinisaniceguy
+
+Name: Kenton Gray
+GitHub: https://github.com/kentongray
+
+Name: Felix Bünemann
+GitHub: https://github.com/felixbuenemann
+
+Name: Samy Al Zahrani
+GitHub: https://github.com/salzhrani
+
+Name: Chintan Thakkar
+GitHub: https://github.com/lemnisk8
+
+Name: F. Orlando Galashan
+GitHub: https://github.com/frulo
+
+Name: Kleis Auke Wolthuizen
+GitHub: https://github.com/kleisauke
+
+Name: Matt Hirsch
+GitHub: https://github.com/mhirsch
+
+Name: Rahul Nanwani
+GitHub: https://github.com/rnanwani
+
+Name: Matthias Thoemmes
+GitHub: https://github.com/cmtt
+
+Name: Patrick Paskaris
+GitHub: https://github.com/ppaskaris
+
+Name: Jérémy Lal
+GitHub: https://github.com/kapouer
+
+Name: Alice Monday
+GitHub: https://github.com/alice0meta
+
+Name: Kristo Jorgenson
+GitHub: https://github.com/kristojorg
+
+Name: Yves Bos
+GitHub: https://github.com/YvesBos
+
+Name: Nicolas Coden
+GitHub: https://github.com/ncoden
+
+Name: Matt Parrish
+GitHub: https://github.com/pbomb
+
+Name: Matthew McEachen
+GitHub: https://github.com/mceachen
+
+Name: Jarda Kotěšovec
+GitHub: https://github.com/jardakotesovec
+
+Name: Kenric D'Souza
+GitHub: https://github.com/AzureByte
+
+Name: Oleh Aleinyk
+GitHub: https://github.com/oaleynik
+
+Name: Marcel Bretschneider
+GitHub: https://github.com/3epnm
+
+Name: Andrea Bianco
+GitHub: https://github.com/BiancoA
+
+Name: Rik Heywood
+GitHub: https://github.com/rikh42
+
+Name: Thomas Parisot
+GitHub: https://github.com/oncletom
+
+Name: Nathan Graves
+GitHub: https://github.com/woolite64
+
+Name: Tom Lokhorst
+GitHub: https://github.com/tomlokhorst
+
+Name: Espen Hovlandsdal
+GitHub: https://github.com/rexxars
+
+Name: Sylvain Dumont
+GitHub: https://github.com/sylvaindumont
+
+Name: Alun Davies
+GitHub: https://github.com/alundavies
+
+Name: Aidan Hoolachan
+GitHub: https://github.com/ajhool
+
+Name: Axel Eirola
+GitHub: https://github.com/aeirola
+
+Name: Freezy
+GitHub: https://github.com/freezy
+
+Name: Julian Aubourg
+GitHub: https://github.com/jaubourg
+
+Name: Keith Belovay
+GitHub: https://github.com/fromkeith
+
+Name: Michael B. Klein
+GitHub: https://github.com/mbklein
+
+Name: Jakub Michálek
+GitHub: https://github.com/Goues
+
+Name: Ilya Ovdin
+GitHub: https://github.com/iovdin
+
+Name: Andargor
+GitHub: https://github.com/Andargor
+
+Name: Nicolas Stepien
+GitHub: https://github.com/MayhemYDG
+
+Name: Paul Neave
+GitHub: https://github.com/neave
+
+Name: Brendan Kennedy
+GitHub: https://github.com/rustyguts
+
+Name: Brychan Bennett-Odlum
+GitHub: https://github.com/BrychanOdlum
+
+Name: Edward Silverton
+GitHub: https://github.com/edsilv
+
+Name: Dumitru Deveatii
+GitHub: https://github.com/dimadeveatii
+
+Name: Roland Asmann
+GitHub: https://github.com/malice00
+
+Name: Roman Malieiev
+GitHub: https://github.com/romaleev
+
+Name: Jerome Vouillon
+GitHub: https://github.com/vouillon
+
+Name: Tomáš Szabo
+GitHub: https://github.com/deftomat
+
+Name: Robert O'Rourke
+GitHub: https://github.com/roborourke
+
+Name: Denis Soldatov
+GitHub: https://github.com/derom
+
+Name: Stefan Probst
+GitHub: https://github.com/stefanprobst
+
+Name: Thomas Beiganz
+GitHub: https://github.com/beig
+
+Name: Florian Busch
+GitHub: https://github.com/florian-busch
+
+Name: Matthieu Salettes
+GitHub: https://github.com/msalettes
+
+Name: Taneli Vatanen
+GitHub: https://github.com/Daiz
+
+Name: Mart Jansink
+GitHub: https://github.com/mart-jansink
+
+Name: Tenpi
+GitHub: https://github.com/Tenpi
+
+Name: Zaruike
+GitHub: https://github.com/Zaruike
+
+Name: Erlend F
+GitHub: https://github.com/erf

docs/image/sharp-logo-mono.svg

@@ -0,0 +1,11 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="86 86 550 550">
+<!-- Creative Commons CC0 1.0 Universal Public Domain Dedication -->
+  <defs>
+    <mask id="c">
+      <path fill="none" stroke="#fff" stroke-width="80" d="M258.411 285.777l200.176-26.8M244.113 466.413L451.44 438.66m.001 0V238.484m0-150.121v171.572l178.725-23.917m-359.843 19.584V477.22m2.387 156.95V462.591L93.984 486.515"/>
+      <path fill="none" stroke="#000" stroke-width="112" d="M451.441 610.246V438.66l178.725-23.91M269.688 112.59v171.58L90.964 308.093"/>
+    </mask>
+  </defs>
+  <path mask="url(#c)" fill="none" stroke="#000" stroke-width="80" d="M258.411 285.777l200.176-26.8M244.113 466.413L451.44 438.66m.001 0V238.484m0-150.121v171.572l178.725-23.917m-359.843 19.584V477.22m2.387 156.95V462.591L93.984 486.515"/>
+  <path fill="none" stroke="#000" stroke-width="80" d="M451.441 610.246V438.66l178.725-23.91M269.688 112.59v171.58L90.964 308.093"/>
+</svg>

docs/image/sharp-logo.svg

@@ -0,0 +1,5 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="86 86 550 550">
+<!-- Creative Commons CC0 1.0 Universal Public Domain Dedication -->
+<path fill="none" stroke="#9c0" stroke-width="80" d="M258.411 285.777l200.176-26.8M244.113 466.413L451.44 438.66M451.441 438.66V238.484M451.441 88.363v171.572l178.725-23.917M270.323 255.602V477.22M272.71 634.17V462.591L93.984 486.515"/>
+<path fill="none" stroke="#090" stroke-width="80" d="M451.441 610.246V438.66l178.725-23.91M269.688 112.59v171.58L90.964 308.093"/>
+</svg>

docs/index.md

@@ -1,127 +0,0 @@
-# sharp
-
-The typical use case for this high speed Node.js module
-is to convert large images in common formats to
-smaller, web-friendly JPEG, PNG and WebP images of varying dimensions.
-
-Resizing an image is typically 4x-5x faster than using the
-quickest ImageMagick and GraphicsMagick settings.
-
-Colour spaces, embedded ICC profiles and alpha transparency channels are all handled correctly.
-Lanczos resampling ensures quality is not sacrificed for speed.
-
-As well as image resizing, operations such as
-rotation, extraction, compositing and gamma correction are available.
-
-OS X, Windows (x64), Linux (x64, ARM) systems do not require
-the installation of any external runtime dependencies.
-
-[![Test Coverage](https://coveralls.io/repos/lovell/sharp/badge.png?branch=master)](https://coveralls.io/r/lovell/sharp?branch=master)
-
-### Formats
-
-This module supports reading JPEG, PNG, WebP, TIFF, GIF and SVG images.
-
-Output images can be in JPEG, PNG, WebP and TIFF formats as well as uncompressed raw pixel data.
-
-Streams, Buffer objects and the filesystem can be used for input and output.
-
-A single input Stream can be split into multiple processing pipelines and output Streams.
-
-Deep Zoom image pyramids can be generated,
-suitable for use with "slippy map" tile viewers like
-[OpenSeadragon](https://github.com/openseadragon/openseadragon)
-and [Leaflet](https://github.com/turban/Leaflet.Zoomify).
-
-### Fast
-
-This module is powered by the blazingly fast
-[libvips](https://github.com/jcupitt/libvips) image processing library,
-originally created in 1989 at Birkbeck College
-and currently maintained by
-[John Cupitt](https://github.com/jcupitt).
-
-Only small regions of uncompressed image data
-are held in memory and processed at a time,
-taking full advantage of multiple CPU cores and L1/L2/L3 cache.
-
-Everything remains non-blocking thanks to _libuv_,
-no child processes are spawned and Promises/A+ are supported.
-
-### Optimal
-
-Huffman tables are optimised when generating JPEG output images
-without having to use separate command line tools like
-[jpegoptim](https://github.com/tjko/jpegoptim) and
-[jpegtran](http://jpegclub.org/jpegtran/).
-
-PNG filtering is disabled by default,
-which for diagrams and line art often produces the same result
-as [pngcrush](https://pmt.sourceforge.io/pngcrush/).
-
-### Contributing
-
-A [guide for contributors](https://github.com/lovell/sharp/blob/master/CONTRIBUTING.md)
-covers reporting bugs, requesting features and submitting code changes.
-
-### Credits
-
-This module would never have been possible without
-the help and code contributions of the following people:
-
-* [John Cupitt](https://github.com/jcupitt)
-* [Pierre Inglebert](https://github.com/pierreinglebert)
-* [Jonathan Ong](https://github.com/jonathanong)
-* [Chanon Sajjamanochai](https://github.com/chanon)
-* [Juliano Julio](https://github.com/julianojulio)
-* [Daniel Gasienica](https://github.com/gasi)
-* [Julian Walker](https://github.com/julianwa)
-* [Amit Pitaru](https://github.com/apitaru)
-* [Brandon Aaron](https://github.com/brandonaaron)
-* [Andreas Lind](https://github.com/papandreou)
-* [Maurus Cuelenaere](https://github.com/mcuelenaere)
-* [Linus Unnebäck](https://github.com/LinusU)
-* [Victor Mateevitsi](https://github.com/mvictoras)
-* [Alaric Holloway](https://github.com/skedastik)
-* [Bernhard K. Weisshuhn](https://github.com/bkw)
-* [David A. Carley](https://github.com/dacarley)
-* [John Tobin](https://github.com/jtobinisaniceguy)
-* [Kenton Gray](https://github.com/kentongray)
-* [Felix Bünemann](https://github.com/felixbuenemann)
-* [Samy Al Zahrani](https://github.com/salzhrani)
-* [Chintan Thakkar](https://github.com/lemnisk8)
-* [F. Orlando Galashan](https://github.com/frulo)
-* [Kleis Auke Wolthuizen](https://github.com/kleisauke)
-* [Matt Hirsch](https://github.com/mhirsch)
-* [Rahul Nanwani](https://github.com/rnanwani)
-* [Matthias Thoemmes](https://github.com/cmtt)
-* [Patrick Paskaris](https://github.com/ppaskaris)
-* [Jérémy Lal](https://github.com/kapouer)
-* [Alice Monday](https://github.com/alice0meta)
-* [Kristo Jorgenson](https://github.com/kristojorg)
-* [Yves Bos](https://github.com/YvesBos)
-* [Nicolas Coden](https://github.com/ncoden)
-* [Matt Parrish](https://github.com/pbomb)
-* [Matthew McEachen](https://github.com/mceachen)
-* [Jarda Kotěšovec](https://github.com/jardakotesovec)
-* [Kenric D'Souza](https://github.com/AzureByte)
-* [Oleh Aleinyk](https://github.com/oaleynik)
-* [Marcel Bretschneider](https://github.com/3epnm)
-* [Andrea Bianco](https://github.com/BiancoA)
-
-Thank you!
-
-### Licence
-
-Copyright 2013, 2014, 2015, 2016, 2017, 2018 Lovell Fuller and contributors.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-[http://www.apache.org/licenses/LICENSE-2.0](http://www.apache.org/licenses/LICENSE-2.0.html)
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.

docs/install.md

@@ -8,84 +8,161 @@ npm install sharp
 yarn add sharp
 ```
 
-### Prerequisites
+## Prerequisites
 
-* Node v4.5.0+
-* C++11 compatible compiler such as gcc 4.8+, clang 3.0+ or MSVC 2013+
-* [node-gyp](https://github.com/TooTallNate/node-gyp#installation) and its dependencies (includes Python)
+* Node.js >= 12.13.0
 
-### Linux
+## Prebuilt binaries
 
-[![Ubuntu 16.04 Build Status](https://travis-ci.org/lovell/sharp.png?branch=master)](https://travis-ci.org/lovell/sharp)
+Ready-compiled sharp and libvips binaries are provided for use on the most common platforms:
 
-libvips and its dependencies are fetched and stored within `node_modules/sharp/vendor` during `npm install`.
-This involves an automated HTTPS download of approximately 7MB.
+* macOS x64 (>= 10.13)
+* macOS ARM64
+* Linux x64 (glibc >= 2.17, musl >= 1.1.24)
+* Linux ARM64 (glibc >= 2.29, musl >= 1.1.24)
+* Windows x64
+* Windows x86
 
-Most recent Linux-based operating systems with glibc running on x64 and ARMv6+ CPUs should "just work", e.g.:
+An ~7MB tarball containing libvips and its most commonly used dependencies
+is downloaded via HTTPS and stored within `node_modules/sharp/vendor` during `npm install`.
 
-* Debian 7, 8
-* Ubuntu 14.04, 16.04
-* Centos 7
-* Fedora
-* openSUSE 13.2
-* Archlinux
-* Raspbian Jessie
-* Amazon Linux 2017.03.1
-* Solus
+This provides support for the
+JPEG, PNG, WebP, AVIF, TIFF, GIF (input) and SVG (input) image formats.
 
-To use a globally-installed version of libvips instead of the provided binaries,
+The following platforms have prebuilt libvips but not sharp:
+
+* Linux ARMv7 (glibc >= 2.28)
+* Linux ARMv6 (glibc >= 2.28)
+* Windows ARM64
+
+The following platforms require compilation of both libvips and sharp from source:
+
+* Linux x86
+* Linux x64 (glibc <= 2.16, includes RHEL/CentOS 6)
+* Linux ARM64 (glibc <= 2.28)
+* Linux ARMv7 (glibc <= 2.27, musl)
+* Linux ARMv6 (glibc <= 2.27, musl)
+* Linux PowerPC
+* FreeBSD
+* OpenBSD
+
+## Common problems
+
+The architecture and platform of Node.js used for `npm install`
+must be the same as the architecture and platform of Node.js used at runtime.
+See the [cross-platform](#cross-platform) section if this is not the case.
+
+When using npm v6 or earlier, the `npm install --unsafe-perm` flag must be used when installing as `root` or a `sudo` user.
+
+When using npm v7, the user running `npm install` must own the directory it is run in.
+
+The `npm install --ignore-scripts=false` flag must be used when `npm` has been configured to ignore installation scripts.
+
+Check the output of running `npm install --verbose sharp` for useful error messages.
+
+## Apple M1
+
+Prebuilt sharp and libvips binaries are provided for macOS on ARM64 from sharp v0.29.0.
+
+Prebuilt libvips binaries were provided for macOS on ARM64 from sharp v0.28.0.
+
+## Cross-platform
+
+At `npm install` time, prebuilt binaries are automatically selected for the
+current OS platform and CPU architecture, where available.
+
+The target platform and/or architecture can be manually selected using the following flags.
+
+```sh
+npm install --platform=... --arch=... --arm-version=... sharp
+```
+
+* `--platform`: one of `linux`, `linuxmusl`, `darwin` or `win32`.
+* `--arch`: one of `x64`, `ia32`, `arm` or `arm64`.
+* `--arm-version`: one of `6`, `7` or `8` (`arm` defaults to `6`, `arm64` defaults to `8`).
+* `--sharp-install-force`: skip version compatibility checks.
+
+These values can also be set via environment variables,
+`npm_config_platform`, `npm_config_arch`, `npm_config_arm_version`
+and `SHARP_INSTALL_FORCE` respectively.
+
+For example, if the target machine has a 64-bit ARM CPU and is running Alpine Linux,
+use the following flags:
+
+```sh
+npm install --arch=arm64 --platform=linuxmusl sharp
+```
+
+## Custom libvips
+
+To use a custom, globally-installed version of libvips instead of the provided binaries,
 make sure it is at least the version listed under `config.libvips` in the `package.json` file
 and that it can be located using `pkg-config --modversion vips-cpp`.
 
-If you are using non-stadard paths (anything other than `/usr` or `/usr/local`),
-you might need to set `PKG_CONFIG_PATH` during `npm install`
-and `LD_LIBRARY_PATH` at runtime.
+For help compiling libvips from source, please see
+[https://libvips.github.io/libvips/install.html#building-libvips-from-a-source-tarball](https://libvips.github.io/libvips/install.html#building-libvips-from-a-source-tarball).
 
-This allows the use of newer versions of libvips with older versions of sharp.
+The use of a globally-installed libvips is unsupported on Windows.
 
-For 32-bit Intel CPUs and older Linux-based operating systems such as Centos 6,
-it is recommended to install a system-wide installation of libvips from source:
+## Building from source
 
-https://jcupitt.github.io/libvips/install.html#building-libvips-from-a-source-tarball
+This module will be compiled from source at `npm install` time when:
 
-#### Alpine Linux
+* a globally-installed libvips is detected (set the `SHARP_IGNORE_GLOBAL_LIBVIPS` environment variable to skip this),
+* prebuilt sharp binaries do not exist for the current platform, or
+* when the `npm install --build-from-source` flag is used.
 
-libvips is available in the
-[testing repository](https://pkgs.alpinelinux.org/packages?name=vips-dev):
+Building from source requires:
+
+* C++11 compiler
+* [node-gyp](https://github.com/nodejs/node-gyp#installation) and its dependencies
+
+## Custom prebuilt binaries
+
+This is an advanced approach that most people will not require.
+
+To install the prebuilt sharp binaries from a custom URL,
+set the `sharp_binary_host` npm config option
+or the `npm_config_sharp_binary_host` environment variable.
+
+To install the prebuilt sharp binaries from a directory on the local filesystem,
+set the `sharp_local_prebuilds` npm config option
+or the `npm_config_sharp_local_prebuilds` environment variable.
+
+To install the prebuilt libvips binaries from a custom URL,
+set the `sharp_libvips_binary_host` npm config option
+or the `npm_config_sharp_libvips_binary_host` environment variable.
+
+The version subpath and file name are appended to these.
+For example, if `sharp_libvips_binary_host` is set to `https://hostname/path`
+and the libvips version is `1.2.3` then the resultant URL will be
+`https://hostname/path/v1.2.3/libvips-1.2.3-platform-arch.tar.br`.
+
+See the Chinese mirror below for a further example.
+
+## Chinese mirror
+
+A mirror site based in China, provided by Alibaba, contains binaries for both sharp and libvips.
+
+To use this either set the following configuration:
 
 ```sh
-apk add vips-dev fftw-dev --update-cache --repository https://dl-3.alpinelinux.org/alpine/edge/testing/
+npm config set sharp_binary_host "https://npm.taobao.org/mirrors/sharp"
+npm config set sharp_libvips_binary_host "https://npm.taobao.org/mirrors/sharp-libvips"
+npm install sharp
 ```
 
-The smaller stack size of musl libc means
-libvips may need to be used without a cache
-via `sharp.cache(false)` to avoid a stack overflow.
+or set the following environment variables:
 
-### Mac OS
+```sh
+npm_config_sharp_binary_host="https://npm.taobao.org/mirrors/sharp" \
+  npm_config_sharp_libvips_binary_host="https://npm.taobao.org/mirrors/sharp-libvips" \
+  npm install sharp
+```
 
-[![OS X 10.9.5 Build Status](https://travis-ci.org/lovell/sharp.png?branch=master)](https://travis-ci.org/lovell/sharp)
+## FreeBSD
 
-libvips and its dependencies are fetched and stored within `node_modules/sharp/vendor` during `npm install`.
-This involves an automated HTTPS download of approximately 7MB.
-
-To use your own version of libvips instead of the provided binaries, make sure it is
-at least the version listed under `config.libvips` in the `package.json` file and
-that it can be located using `pkg-config --modversion vips-cpp`.
-
-### Windows x64
-
-[![Windows x64 Build Status](https://ci.appveyor.com/api/projects/status/pgtul704nkhhg6sg)](https://ci.appveyor.com/project/lovell/sharp)
-
-libvips and its dependencies are fetched and stored within `node_modules\sharp\vendor` during `npm install`.
-This involves an automated HTTPS download of approximately 12MB.
-
-Only 64-bit (x64) `node.exe` is supported.
-
-### FreeBSD
-
-libvips must be installed before `npm install` is run.
-
-This can be achieved via package or ports:
+The `vips` package must be installed before `npm install` is run.
 
 ```sh
 pkg install -y pkgconf vips
@@ -95,155 +172,78 @@ pkg install -y pkgconf vips
 cd /usr/ports/graphics/vips/ && make install clean
 ```
 
-FreeBSD's gcc v4 and v5 need `CXXFLAGS=-D_GLIBCXX_USE_C99` set for C++11 support due to
-https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=193528
+## Linux memory allocator
 
-### Heroku
+The default memory allocator on most glibc-based Linux systems
+(e.g. Debian, Red Hat) is unsuitable for long-running, multi-threaded
+processes that involve lots of small memory allocations.
 
-libvips and its dependencies are fetched and stored within `node_modules\sharp\vendor` during `npm install`.
-This involves an automated HTTPS download of approximately 7MB.
+For this reason, by default, sharp will limit the use of thread-based
+[concurrency](api-utility#concurrency) when the glibc allocator is
+detected at runtime.
 
-Set [NODE_MODULES_CACHE](https://devcenter.heroku.com/articles/nodejs-support#cache-behavior)
+To help avoid fragmentation and improve performance on these systems,
+the use of an alternative memory allocator such as
+[jemalloc](https://github.com/jemalloc/jemalloc) is recommended.
+
+Those using musl-based Linux (e.g. Alpine) and non-Linux systems are
+unaffected.
+
+## Heroku
+
+Add the
+[jemalloc buildpack](https://github.com/gaffneyc/heroku-buildpack-jemalloc)
+to reduce the effects of memory fragmentation.
+
+Set
+[NODE_MODULES_CACHE](https://devcenter.heroku.com/articles/nodejs-support#cache-behavior)
 to `false` when using the `yarn` package manager.
 
-### Docker
+## AWS Lambda
 
-[Marc Bachmann](https://github.com/marcbachmann) maintains an
-[Ubuntu-based Dockerfile for libvips](https://github.com/marcbachmann/dockerfile-libvips).
+The `node_modules` directory of the
+[deployment package](https://docs.aws.amazon.com/lambda/latest/dg/nodejs-package.html)
+must include binaries for the Linux x64 platform.
+
+When building your deployment package on machines other than Linux x64 (glibc),
+run the following additional command after `npm install`:
 
 ```sh
-docker pull marcbachmann/libvips
+npm install
+SHARP_IGNORE_GLOBAL_LIBVIPS=1 npm install --arch=x64 --platform=linux sharp
 ```
 
-[Will Jordan](https://github.com/wjordan) maintains an
-[Alpine-based Dockerfile for libvips](https://github.com/wjordan/dockerfile-libvips).
+To get the best performance select the largest memory available.
+A 1536 MB function provides ~12x more CPU time than a 128 MB function.
 
-```sh
-docker pull wjordan/libvips
+## Webpack
+
+Ensure sharp is added to the
+[externals](https://webpack.js.org/configuration/externals/)
+configuration.
+
+```js
+externals: {
+  'sharp': 'commonjs sharp'
+}
 ```
 
-[Tailor Brands](https://github.com/TailorBrands) maintain
-[Debian-based Dockerfiles for libvips and nodejs](https://github.com/TailorBrands/docker-libvips).
+## Worker threads
 
-```sh
-docker pull tailor/docker-libvips
+The main thread must call `require('sharp')`
+before worker threads are created
+to ensure shared libraries remain loaded in memory
+until after all threads are complete.
+
+## Known conflicts
+
+### Canvas and Windows
+
+The prebuilt binaries provided by `canvas` for Windows depend on the unmaintained GTK 2, last updated in 2011.
+
+These conflict with the modern, up-to-date binaries provided by sharp.
+
+If both modules are used in the same Windows process, the following error will occur:
 ```
-
-### AWS Lambda
-
-A [deployment package](http://docs.aws.amazon.com/lambda/latest/dg/nodejs-create-deployment-pkg.html) for the
-[Lambda Execution Environment](http://docs.aws.amazon.com/lambda/latest/dg/current-supported-versions.html)
-can be built using Docker.
-
-```sh
-rm -rf node_modules/sharp
-docker run -v "$PWD":/var/task lambci/lambda:build-nodejs6.10 npm install
+The specified procedure could not be found.
 ```
-
-Set the Lambda runtime to Node.js 6.10.
-
-To get the best performance select the largest memory available. A 1536 MB function provides ~12x more CPU time than a 128 MB function.
-
-### Build tools
-
-* [gulp-responsive](https://www.npmjs.com/package/gulp-responsive)
-* [grunt-sharp](https://www.npmjs.com/package/grunt-sharp)
-
-### Coding tools
-
-* [Sharp TypeScript Types](https://www.npmjs.com/package/@types/sharp)
-
-### CLI tools
-
-* [sharp-cli](https://www.npmjs.com/package/sharp-cli)
-
-### Security
-
-Many users of this module process untrusted, user-supplied images,
-but there are aspects of security to consider when doing so.
-
-It is possible to compile libvips with support for various third-party image loaders.
-Each of these libraries has undergone differing levels of security testing.
-
-Whilst tools such as [American Fuzzy Lop](http://lcamtuf.coredump.cx/afl/)
-and [Valgrind](http://valgrind.org/) have been used to test
-the most popular web-based formats, as well as libvips itself,
-you are advised to perform your own testing and sandboxing.
-
-ImageMagick in particular has a relatively large attack surface,
-which can be partially mitigated with a
-[policy.xml](http://www.imagemagick.org/script/resources.php)
-configuration file to prevent the use of coders known to be vulnerable.
-
-```xml
-<policymap>
-  <policy domain="coder" rights="none" pattern="EPHEMERAL" />
-  <policy domain="coder" rights="none" pattern="URL" />
-  <policy domain="coder" rights="none" pattern="HTTPS" />
-  <policy domain="coder" rights="none" pattern="MVG" />
-  <policy domain="coder" rights="none" pattern="MSL" />
-  <policy domain="coder" rights="none" pattern="TEXT" />
-  <policy domain="coder" rights="none" pattern="SHOW" />
-  <policy domain="coder" rights="none" pattern="WIN" />
-  <policy domain="coder" rights="none" pattern="PLT" />
-</policymap>
-```
-
-Set the `MAGICK_CONFIGURE_PATH` environment variable
-to the directory containing the `policy.xml` file.
-
-### Pre-compiled libvips binaries
-
-If a global installation of libvips that meets the
-minimum version requirement cannot be found,
-this module will attempt to download a pre-compiled bundle of libvips
-and its dependencies on Linux and Windows machines.
-
-Should you need to manually download and inspect these files,
-you can do so via https://github.com/lovell/sharp-libvips/releases
-
-Should you wish to install these from your own location,
-set the `SHARP_DIST_BASE_URL` environment variable, e.g.
-
-```sh
-SHARP_DIST_BASE_URL="https://hostname/path/" npm install sharp
-```
-
-to use `https://hostname/path/libvips-x.y.z-platform.tar.gz`.
-
-### Licences
-
-This module is licensed under the terms of the
-[Apache 2.0 Licence](https://github.com/lovell/sharp/blob/master/LICENSE).
-
-The libraries downloaded and used by this module
-are done so under the terms of the following licences,
-all of which are compatible with the Apache 2.0 Licence.
-
-Use of libraries under the terms of the LGPLv3 is via the
-"any later version" clause of the LGPLv2 or LGPLv2.1.
-
-| Library       | Used under the terms of                                                                                  |
-|---------------|----------------------------------------------------------------------------------------------------------|
-| cairo         | Mozilla Public License 2.0                                                                               |
-| expat         | MIT Licence                                                                                              |
-| fontconfig    | [fontconfig Licence](https://cgit.freedesktop.org/fontconfig/tree/COPYING) (BSD-like)                    |
-| freetype      | [freetype Licence](http://git.savannah.gnu.org/cgit/freetype/freetype2.git/tree/docs/FTL.TXT) (BSD-like) |
-| giflib        | MIT Licence                                                                                              |
-| glib          | LGPLv3                                                                                                   |
-| harfbuzz      | MIT Licence                                                                                              |
-| lcms          | MIT Licence                                                                                              |
-| libcroco      | LGPLv3                                                                                                   |
-| libexif       | LGPLv3                                                                                                   |
-| libffi        | MIT Licence                                                                                              |
-| libgsf        | LGPLv3                                                                                                   |
-| libjpeg-turbo | [zlib License, IJG License](https://github.com/libjpeg-turbo/libjpeg-turbo/blob/master/LICENSE.md)       |
-| libpng        | [libpng License](http://www.libpng.org/pub/png/src/libpng-LICENSE.txt)                                   |
-| librsvg       | LGPLv3                                                                                                   |
-| libtiff       | [libtiff License](http://www.libtiff.org/misc.html) (BSD-like)                                           |
-| libvips       | LGPLv3                                                                                                   |
-| libwebp       | New BSD License                                                                                          |
-| libxml2       | MIT Licence                                                                                              |
-| pango         | LGPLv3                                                                                                   |
-| pixman        | MIT Licence                                                                                              |
-| zlib          | [zlib Licence](https://github.com/madler/zlib/blob/master/zlib.h)                                        |

docs/performance.md

@@ -1,52 +1,50 @@
 # Performance
 
-### Test environment
+A test to benchmark the performance of this module relative to alternatives.
 
-* AWS EC2 eu-west-1 [c5.large](https://aws.amazon.com/ec2/instance-types/c5/) (2x Xeon Platinum 8124M CPU @ 3.00GHz)
-* Ubuntu 17.10 (hvm:ebs-ssd, 20180102, ami-0741d47e)
-* Node.js v8.9.4
+## The contenders
 
-### The contenders
-
-* [jimp](https://www.npmjs.com/package/jimp) v0.2.28 - Image processing in pure JavaScript. Bilinear interpolation only.
-* [pajk-lwip](https://www.npmjs.com/package/pajk-lwip) v0.2.0 (fork) - Wrapper around CImg that compiles dependencies from source.
-* [mapnik](https://www.npmjs.org/package/mapnik) v3.6.2 - Whilst primarily a map renderer, Mapnik contains bitmap image utilities.
-* [imagemagick-native](https://www.npmjs.com/package/imagemagick-native) v1.9.3 - Wrapper around libmagick++, supports Buffers only.
+* [jimp](https://www.npmjs.com/package/jimp) v0.16.1 - Image processing in pure JavaScript. Provides bicubic interpolation.
+* [mapnik](https://www.npmjs.org/package/mapnik) v4.5.8 - Whilst primarily a map renderer, Mapnik contains bitmap image utilities.
 * [imagemagick](https://www.npmjs.com/package/imagemagick) v0.1.3 - Supports filesystem only and "*has been unmaintained for a long time*".
 * [gm](https://www.npmjs.com/package/gm) v1.23.1 - Fully featured wrapper around GraphicsMagick's `gm` command line utility.
-* [images](https://www.npmjs.com/package/images) v3.0.1 - Compiles dependencies from source. Provides bicubic interpolation.
-* sharp v0.19.0 / libvips v8.6.1 - Caching within libvips disabled to ensure a fair comparison.
+* [@squoosh/lib](https://www.npmjs.com/package/@squoosh/lib) v0.4.0 - Image libraries transpiled to WebAssembly, includes GPLv3 code.
+* [@squoosh/cli](https://www.npmjs.com/package/@squoosh/cli) v0.7.2 - Command line wrapper around `@squoosh/lib`, avoids GPLv3 by spawning process.
+* sharp v0.28.0 / libvips v8.10.6 - Caching within libvips disabled to ensure a fair comparison.
 
-### The task
+## The task
 
 Decompress a 2725x2225 JPEG image,
 resize to 720x588 using Lanczos 3 resampling (where available),
 then compress to JPEG at a "quality" setting of 80.
 
-### Results
+## Test environment
+
+* AWS EC2 eu-west-1 [c5ad.xlarge](https://aws.amazon.com/ec2/instance-types/c5/) (4x AMD EPYC 7R32)
+* Ubuntu 21.04 (ami-0d7626a9c2ceab1ac)
+* Node.js 16.6.2
+
+## Results
 
 | Module             | Input  | Output | Ops/sec | Speed-up |
 | :----------------- | :----- | :----- | ------: | -------: |
-| jimp (bilinear)    | buffer | buffer |    1.14 |      1.0 |
-| lwip               | buffer | buffer |    1.86 |      1.6 |
-| mapnik             | buffer | buffer |    3.34 |      2.9 |
-| imagemagick-native | buffer | buffer |    4.13 |      3.6 |
-| gm                 | buffer | buffer |    4.21 |      3.7 |
-| gm                 | file   | file   |    4.27 |      3.7 |
-| imagemagick        | file   | file   |    4.67 |      4.1 |
-| images (bicubic)   | file   | file   |    6.22 |      5.5 |
-| sharp              | stream | stream |   24.43 |     21.4 |
-| sharp              | file   | file   |   25.97 |     22.7 |
-| sharp              | file   | buffer |   26.00 |     22.8 |
-| sharp              | buffer | file   |   26.33 |     23.0 |
-| sharp              | buffer | buffer |   26.43 |     23.1 |
+| jimp               | buffer | buffer |    0.83 |      1.0 |
+| squoosh-cli        | file   | file   |    1.09 |      1.3 |
+| squoosh-lib        | buffer | buffer |    1.83 |      2.2 |
+| mapnik             | buffer | buffer |    3.41 |      4.1 |
+| gm                 | buffer | buffer |    8.34 |     10.0 |
+| imagemagick        | file   | file   |    8.67 |     10.4 |
+| gm                 | file   | file   |    8.82 |     10.6 |
+| sharp              | stream | stream |   29.44 |     35.5 |
+| sharp              | file   | file   |   29.64 |     35.7 |
+| sharp              | buffer | buffer |   31.09 |     37.5 |
 
 Greater libvips performance can be expected with caching enabled (default)
 and using 8+ core machines, especially those with larger L1/L2 CPU caches.
 
 The I/O limits of the relevant (de)compression library will generally determine maximum throughput.
 
-### Benchmark test prerequisites
+## Running the benchmark test
 
 Requires _ImageMagick_, _GraphicsMagick_ and _Mapnik_:
 
@@ -57,19 +55,17 @@ brew install mapnik
 ```
 
 ```sh
-sudo apt-get install imagemagick libmagick++-dev graphicsmagick mapnik-dev
+sudo apt-get install build-essential imagemagick libmagick++-dev graphicsmagick libmapnik-dev
 ```
 
 ```sh
 sudo yum install ImageMagick-devel ImageMagick-c++-devel GraphicsMagick mapnik-devel
 ```
 
-### Running the benchmark test
-
 ```sh
 git clone https://github.com/lovell/sharp.git
 cd sharp
-npm install
+npm install --build-from-source
 cd test/bench
 npm install
 npm test

docs/robots.txt

@@ -0,0 +1,2 @@
+User-agent: *
+Disallow:

docs/search-index/build.js

@@ -0,0 +1,61 @@
+'use strict';
+
+const fs = require('fs');
+const path = require('path');
+const { extractDescription, extractKeywords, extractParameters } = require('./extract');
+
+const searchIndex = [];
+
+// Install
+const contents = fs.readFileSync(path.join(__dirname, '..', 'install.md'), 'utf8');
+const matches = contents.matchAll(
+  /## (?<title>[A-Za-z0-9 ]+)\n\n(?<body>[^#]+)/gs
+);
+for (const match of matches) {
+  const { title, body } = match.groups;
+  const description = extractDescription(body);
+
+  searchIndex.push({
+    t: title,
+    d: description,
+    k: extractKeywords(`${title} ${description}`),
+    l: `/install#${title.toLowerCase().replace(/ /g, '-')}`
+  });
+}
+
+// API
+[
+  'constructor',
+  'input',
+  'output',
+  'resize',
+  'composite',
+  'operation',
+  'channel',
+  'colour',
+  'utility'
+].forEach((section) => {
+  const contents = fs.readFileSync(path.join(__dirname, '..', `api-${section}.md`), 'utf8');
+  const matches = contents.matchAll(
+    /\n## (?<title>[A-Za-z]+)\n\n(?<firstparagraph>.+?)\n\n(?<parameters>### Parameters.+?Returns)?/gs
+  );
+  for (const match of matches) {
+    const { title, firstparagraph, parameters } = match.groups;
+    const description = firstparagraph.startsWith('###')
+      ? 'Constructor'
+      : extractDescription(firstparagraph);
+    const parameterNames = parameters ? extractParameters(parameters) : '';
+
+    searchIndex.push({
+      t: title,
+      d: description,
+      k: extractKeywords(`${title} ${description} ${parameterNames}`),
+      l: `/api-${section}#${title.toLowerCase()}`
+    });
+  }
+});
+
+fs.writeFileSync(
+  path.join(__dirname, '..', 'search-index.json'),
+  JSON.stringify(searchIndex)
+);

docs/search-index/extract.js

@@ -0,0 +1,30 @@
+'use strict';
+
+const stopWords = require('./stop-words');
+
+const extractDescription = (str) =>
+  str
+    .replace(/### Examples.*/sg, '')
+    .replace(/\(http[^)]+/g, '')
+    .replace(/\s+/g, ' ')
+    .replace(/[^A-Za-z0-9_/\-,. ]/g, '')
+    .replace(/\s+/g, ' ')
+    .substr(0, 180)
+    .trim();
+
+const extractParameters = (str) =>
+  [...str.matchAll(/options\.(?<name>[^.`]+)/gs)]
+    .map((match) => match.groups.name)
+    .join(' ');
+
+const extractKeywords = (str) =>
+  [
+    ...new Set(
+      str
+        .split(/[ -/]/)
+        .map((word) => word.toLowerCase().replace(/[^a-z]/g, ''))
+        .filter((word) => word.length > 2 && word.length < 15 && !stopWords.includes(word))
+    )
+  ].join(' ');
+
+module.exports = { extractDescription, extractKeywords, extractParameters };

docs/search-index/stop-words.js

@@ -0,0 +1,100 @@
+'use strict';
+
+module.exports = [
+  'about',
+  'after',
+  'all',
+  'allows',
+  'already',
+  'also',
+  'alternative',
+  'always',
+  'and',
+  'any',
+  'are',
+  'based',
+  'been',
+  'before',
+  'both',
+  'call',
+  'callback',
+  'can',
+  'containing',
+  'default',
+  'does',
+  'each',
+  'either',
+  'ensure',
+  'etc',
+  'every',
+  'except',
+  'for',
+  'from',
+  'get',
+  'gets',
+  'given',
+  'has',
+  'have',
+  'how',
+  'image',
+  'involve',
+  'its',
+  'least',
+  'lots',
+  'may',
+  'more',
+  'most',
+  'much',
+  'must',
+  'non',
+  'not',
+  'occur',
+  'occurs',
+  'options',
+  'other',
+  'out',
+  'over',
+  'perform',
+  'performs',
+  'provide',
+  'provided',
+  'ready',
+  'requires',
+  'returned',
+  'same',
+  'see',
+  'set',
+  'sets',
+  'should',
+  'since',
+  'spelling',
+  'such',
+  'support',
+  'supported',
+  'sure',
+  'take',
+  'than',
+  'that',
+  'the',
+  'their',
+  'then',
+  'there',
+  'therefore',
+  'these',
+  'this',
+  'under',
+  'unless',
+  'until',
+  'use',
+  'used',
+  'using',
+  'value',
+  'values',
+  'when',
+  'which',
+  'while',
+  'will',
+  'with',
+  'without',
+  'you'
+];

install/can-compile.js

@@ -0,0 +1,11 @@
+'use strict';
+
+const libvips = require('../lib/libvips');
+
+try {
+  if (!(libvips.useGlobalLibvips() || libvips.hasVendoredLibvips())) {
+    process.exitCode = 1;
+  }
+} catch (err) {
+  process.exitCode = 1;
+}

install/dll-copy.js

@@ -0,0 +1,37 @@
+'use strict';
+
+const fs = require('fs');
+const path = require('path');
+
+const libvips = require('../lib/libvips');
+const platform = require('../lib/platform');
+
+const minimumLibvipsVersion = libvips.minimumLibvipsVersion;
+
+const platformAndArch = platform();
+
+if (platformAndArch.startsWith('win32')) {
+  const buildReleaseDir = path.join(__dirname, '..', 'build', 'Release');
+  libvips.log(`Creating ${buildReleaseDir}`);
+  try {
+    libvips.mkdirSync(buildReleaseDir);
+  } catch (err) {}
+  const vendorLibDir = path.join(__dirname, '..', 'vendor', minimumLibvipsVersion, platformAndArch, 'lib');
+  libvips.log(`Copying DLLs from ${vendorLibDir} to ${buildReleaseDir}`);
+  try {
+    fs
+      .readdirSync(vendorLibDir)
+      .filter(function (filename) {
+        return /\.dll$/.test(filename);
+      })
+      .forEach(function (filename) {
+        fs.copyFileSync(
+          path.join(vendorLibDir, filename),
+          path.join(buildReleaseDir, filename)
+        );
+      });
+  } catch (err) {
+    libvips.log(err);
+    process.exit(1);
+  }
+}

install/libvips.js

@@ -0,0 +1,176 @@
+'use strict';
+
+const fs = require('fs');
+const os = require('os');
+const path = require('path');
+const stream = require('stream');
+const zlib = require('zlib');
+
+const detectLibc = require('detect-libc');
+const semverLessThan = require('semver/functions/lt');
+const semverSatisfies = require('semver/functions/satisfies');
+const simpleGet = require('simple-get');
+const tarFs = require('tar-fs');
+
+const agent = require('../lib/agent');
+const libvips = require('../lib/libvips');
+const platform = require('../lib/platform');
+
+const minimumGlibcVersionByArch = {
+  arm: '2.28',
+  arm64: '2.29',
+  x64: '2.17'
+};
+
+const hasSharpPrebuild = [
+  'darwin-x64',
+  'darwin-arm64',
+  'linux-arm64',
+  'linux-x64',
+  'linuxmusl-x64',
+  'linuxmusl-arm64',
+  'win32-ia32',
+  'win32-x64'
+];
+
+const { minimumLibvipsVersion, minimumLibvipsVersionLabelled } = libvips;
+const distHost = process.env.npm_config_sharp_libvips_binary_host || 'https://github.com/lovell/sharp-libvips/releases/download';
+const distBaseUrl = process.env.npm_config_sharp_dist_base_url || process.env.SHARP_DIST_BASE_URL || `${distHost}/v${minimumLibvipsVersionLabelled}/`;
+const installationForced = !!(process.env.npm_config_sharp_install_force || process.env.SHARP_INSTALL_FORCE);
+
+const fail = function (err) {
+  libvips.log(err);
+  if (err.code === 'EACCES') {
+    libvips.log('Are you trying to install as a root or sudo user? Try again with the --unsafe-perm flag');
+  }
+  libvips.log('Please see https://sharp.pixelplumbing.com/install for required dependencies');
+  process.exit(1);
+};
+
+const handleError = function (err) {
+  if (installationForced) {
+    libvips.log(`Installation warning: ${err.message}`);
+  } else {
+    throw err;
+  }
+};
+
+const extractTarball = function (tarPath, platformAndArch) {
+  const versionedVendorPath = path.join(__dirname, '..', 'vendor', minimumLibvipsVersion, platformAndArch);
+  libvips.mkdirSync(versionedVendorPath);
+
+  const ignoreVendorInclude = hasSharpPrebuild.includes(platformAndArch) && !process.env.npm_config_build_from_source;
+  const ignore = function (name) {
+    return ignoreVendorInclude && name.includes('include/');
+  };
+
+  stream.pipeline(
+    fs.createReadStream(tarPath),
+    new zlib.BrotliDecompress(),
+    tarFs.extract(versionedVendorPath, { ignore }),
+    function (err) {
+      if (err) {
+        if (/unexpected end of file/.test(err.message)) {
+          fail(new Error(`Please delete ${tarPath} as it is not a valid tarball`));
+        }
+        fail(err);
+      }
+    }
+  );
+};
+
+try {
+  const useGlobalLibvips = libvips.useGlobalLibvips();
+
+  if (useGlobalLibvips) {
+    const globalLibvipsVersion = libvips.globalLibvipsVersion();
+    libvips.log(`Detected globally-installed libvips v${globalLibvipsVersion}`);
+    libvips.log('Building from source via node-gyp');
+    process.exit(1);
+  } else if (libvips.hasVendoredLibvips()) {
+    libvips.log(`Using existing vendored libvips v${minimumLibvipsVersion}`);
+  } else {
+    // Is this arch/platform supported?
+    const arch = process.env.npm_config_arch || process.arch;
+    const platformAndArch = platform();
+    if (arch === 'ia32' && !platformAndArch.startsWith('win32')) {
+      throw new Error(`Intel Architecture 32-bit systems require manual installation of libvips >= ${minimumLibvipsVersion}`);
+    }
+    if (platformAndArch === 'darwin-arm64') {
+      throw new Error("Please run 'brew install vips' to install libvips on Apple M1 (ARM64) systems");
+    }
+    if (platformAndArch === 'freebsd-x64' || platformAndArch === 'openbsd-x64' || platformAndArch === 'sunos-x64') {
+      throw new Error(`BSD/SunOS systems require manual installation of libvips >= ${minimumLibvipsVersion}`);
+    }
+    // Linux libc version check
+    if (detectLibc.family === detectLibc.GLIBC && detectLibc.version && minimumGlibcVersionByArch[arch]) {
+      if (semverLessThan(`${detectLibc.version}.0`, `${minimumGlibcVersionByArch[arch]}.0`)) {
+        handleError(new Error(`Use with glibc ${detectLibc.version} requires manual installation of libvips >= ${minimumLibvipsVersion}`));
+      }
+    }
+    if (detectLibc.family === detectLibc.MUSL && detectLibc.version) {
+      if (semverLessThan(detectLibc.version, '1.1.24')) {
+        handleError(new Error(`Use with musl ${detectLibc.version} requires manual installation of libvips >= ${minimumLibvipsVersion}`));
+      }
+    }
+    // Node.js minimum version check
+    const supportedNodeVersion = process.env.npm_package_engines_node || require('../package.json').engines.node;
+    if (!semverSatisfies(process.versions.node, supportedNodeVersion)) {
+      handleError(new Error(`Expected Node.js version ${supportedNodeVersion} but found ${process.versions.node}`));
+    }
+
+    // Download to per-process temporary file
+    const tarFilename = ['libvips', minimumLibvipsVersion, platformAndArch].join('-') + '.tar.br';
+    const tarPathCache = path.join(libvips.cachePath(), tarFilename);
+    if (fs.existsSync(tarPathCache)) {
+      libvips.log(`Using cached ${tarPathCache}`);
+      extractTarball(tarPathCache, platformAndArch);
+    } else {
+      const url = distBaseUrl + tarFilename;
+      libvips.log(`Downloading ${url}`);
+      simpleGet({ url: url, agent: agent() }, function (err, response) {
+        if (err) {
+          fail(err);
+        } else if (response.statusCode === 404) {
+          fail(new Error(`Prebuilt libvips ${minimumLibvipsVersion} binaries are not yet available for ${platformAndArch}`));
+        } else if (response.statusCode !== 200) {
+          fail(new Error(`Status ${response.statusCode} ${response.statusMessage}`));
+        } else {
+          const tarPathTemp = path.join(os.tmpdir(), `${process.pid}-${tarFilename}`);
+          const tmpFileStream = fs.createWriteStream(tarPathTemp);
+          response
+            .on('error', function (err) {
+              tmpFileStream.destroy(err);
+            })
+            .on('close', function () {
+              if (!response.complete) {
+                tmpFileStream.destroy(new Error('Download incomplete (connection was terminated)'));
+              }
+            })
+            .pipe(tmpFileStream);
+          tmpFileStream
+            .on('error', function (err) {
+              // Clean up temporary file
+              try {
+                fs.unlinkSync(tarPathTemp);
+              } catch (e) {}
+              fail(err);
+            })
+            .on('close', function () {
+              try {
+                // Attempt to rename
+                fs.renameSync(tarPathTemp, tarPathCache);
+              } catch (err) {
+                // Fall back to copy and unlink
+                fs.copyFileSync(tarPathTemp, tarPathCache);
+                fs.unlinkSync(tarPathTemp);
+              }
+              extractTarball(tarPathCache, platformAndArch);
+            });
+        }
+      });
+    }
+  }
+} catch (err) {
+  fail(err);
+}

lib/agent.js

@@ -20,15 +20,18 @@ function env (key) {
 
 module.exports = function () {
   try {
-    const proxy = url.parse(proxies.map(env).find(is.string));
+    const proxy = new url.URL(proxies.map(env).find(is.string));
     const tunnel = proxy.protocol === 'https:'
       ? tunnelAgent.httpsOverHttps
       : tunnelAgent.httpsOverHttp;
+    const proxyAuth = proxy.username && proxy.password
+      ? `${decodeURIComponent(proxy.username)}:${decodeURIComponent(proxy.password)}`
+      : null;
     return tunnel({
       proxy: {
         port: Number(proxy.port),
         host: proxy.hostname,
-        proxyAuth: proxy.auth
+        proxyAuth
       }
     });
   } catch (err) {

lib/channel.js

@@ -12,35 +12,93 @@ const bool = {
   eor: 'eor'
 };
 
+/**
+ * Remove alpha channel, if any. This is a no-op if the image does not have an alpha channel.
+ *
+ * See also {@link /api-operation#flatten|flatten}.
+ *
+ * @example
+ * sharp('rgba.png')
+ *   .removeAlpha()
+ *   .toFile('rgb.png', function(err, info) {
+ *     // rgb.png is a 3 channel image without an alpha channel
+ *   });
+ *
+ * @returns {Sharp}
+ */
+function removeAlpha () {
+  this.options.removeAlpha = true;
+  return this;
+}
+
+/**
+ * Ensure the output image has an alpha transparency channel.
+ * If missing, the added alpha channel will have the specified
+ * transparency level, defaulting to fully-opaque (1).
+ * This is a no-op if the image already has an alpha channel.
+ *
+ * @since 0.21.2
+ *
+ * @example
+ * // rgba.png will be a 4 channel image with a fully-opaque alpha channel
+ * await sharp('rgb.jpg')
+ *   .ensureAlpha()
+ *   .toFile('rgba.png')
+ *
+ * @example
+ * // rgba is a 4 channel image with a fully-transparent alpha channel
+ * const rgba = await sharp(rgb)
+ *   .ensureAlpha(0)
+ *   .toBuffer();
+ *
+ * @param {number} [alpha=1] - alpha transparency level (0=fully-transparent, 1=fully-opaque)
+ * @returns {Sharp}
+ * @throws {Error} Invalid alpha transparency level
+ */
+function ensureAlpha (alpha) {
+  if (is.defined(alpha)) {
+    if (is.number(alpha) && is.inRange(alpha, 0, 1)) {
+      this.options.ensureAlpha = alpha;
+    } else {
+      throw is.invalidParameterError('alpha', 'number between 0 and 1', alpha);
+    }
+  } else {
+    this.options.ensureAlpha = 1;
+  }
+  return this;
+}
+
 /**
  * Extract a single channel from a multi-channel image.
  *
  * @example
- * sharp(input)
+ * // green.jpg is a greyscale image containing the green channel of the input
+ * await sharp(input)
  *   .extractChannel('green')
- *   .toFile('input_green.jpg', function(err, info) {
- *     // info.channels === 1
- *     // input_green.jpg contains the green channel of the input image
- *    });
+ *   .toFile('green.jpg');
  *
- * @param {Number|String} channel - zero-indexed band number to extract, or `red`, `green` or `blue` as alternative to `0`, `1` or `2` respectively.
+ * @example
+ * // red1 is the red value of the first pixel, red2 the second pixel etc.
+ * const [red1, red2, ...] = await sharp(input)
+ *   .extractChannel(0)
+ *   .raw()
+ *   .toBuffer();
+ *
+ * @param {number|string} channel - zero-indexed channel/band number to extract, or `red`, `green`, `blue` or `alpha`.
  * @returns {Sharp}
  * @throws {Error} Invalid channel
  */
 function extractChannel (channel) {
-  if (channel === 'red') {
-    channel = 0;
-  } else if (channel === 'green') {
-    channel = 1;
-  } else if (channel === 'blue') {
-    channel = 2;
+  const channelMap = { red: 0, green: 1, blue: 2, alpha: 3 };
+  if (Object.keys(channelMap).includes(channel)) {
+    channel = channelMap[channel];
   }
   if (is.integer(channel) && is.inRange(channel, 0, 4)) {
     this.options.extractChannel = channel;
   } else {
-    throw new Error('Cannot extract invalid channel ' + channel);
+    throw is.invalidParameterError('channel', 'integer or one of: red, green, blue, alpha', channel);
   }
-  return this;
+  return this.toColourspace('b-w');
 }
 
 /**
@@ -51,10 +109,10 @@ function extractChannel (channel) {
  * - sRGB: 0: Red, 1: Green, 2: Blue, 3: Alpha.
  * - CMYK: 0: Magenta, 1: Cyan, 2: Yellow, 3: Black, 4: Alpha.
  *
- * Buffers may be any of the image formats supported by sharp: JPEG, PNG, WebP, GIF, SVG, TIFF or raw pixel image data.
+ * Buffers may be any of the image formats supported by sharp.
  * For raw pixel input, the `options` object should contain a `raw` attribute, which follows the format of the attribute of the same name in the `sharp()` constructor.
  *
- * @param {Array<String|Buffer>|String|Buffer} images - one or more images (file paths, Buffers).
+ * @param {Array<string|Buffer>|string|Buffer} images - one or more images (file paths, Buffers).
  * @param {Object} options - image options, see `sharp()` constructor.
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
@@ -82,7 +140,7 @@ function joinChannel (images, options) {
  *     // then `O(1,1) = 0b11110111 & 0b10101010 & 0b00001111 = 0b00000010 = 2`.
  *   });
  *
- * @param {String} boolOp - one of `and`, `or` or `eor` to perform that bitwise operation, like the C logic operators `&`, `|` and `^` respectively.
+ * @param {string} boolOp - one of `and`, `or` or `eor` to perform that bitwise operation, like the C logic operators `&`, `|` and `^` respectively.
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
  */
@@ -90,7 +148,7 @@ function bandbool (boolOp) {
   if (is.string(boolOp) && is.inArray(boolOp, ['and', 'or', 'eor'])) {
     this.options.bandBoolOp = boolOp;
   } else {
-    throw new Error('Invalid bandbool operation ' + boolOp);
+    throw is.invalidParameterError('boolOp', 'one of: and, or, eor', boolOp);
   }
   return this;
 }
@@ -100,13 +158,13 @@ function bandbool (boolOp) {
  * @private
  */
 module.exports = function (Sharp) {
-  // Public instance functions
-  [
+  Object.assign(Sharp.prototype, {
+    // Public instance functions
+    removeAlpha,
+    ensureAlpha,
     extractChannel,
     joinChannel,
     bandbool
-  ].forEach(function (f) {
-    Sharp.prototype[f.name] = f;
   });
   // Class attributes
   Sharp.bool = bool;

lib/colour.js

@@ -16,25 +16,17 @@ const colourspace = {
 };
 
 /**
- * Set the background for the `embed`, `flatten` and `extend` operations.
- * The default background is `{r: 0, g: 0, b: 0, alpha: 1}`, black without transparency.
+ * Tint the image using the provided chroma while preserving the image luminance.
+ * An alpha channel may be present and will be unchanged by the operation.
  *
- * Delegates to the _color_ module, which can throw an Error
- * but is liberal in what it accepts, clipping values to sensible min/max.
- * The alpha value is a float between `0` (transparent) and `1` (opaque).
- *
- * @param {String|Object} rgba - parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
+ * @param {string|Object} rgb - parsed by the [color](https://www.npmjs.org/package/color) module to extract chroma values.
  * @returns {Sharp}
  * @throws {Error} Invalid parameter
  */
-function background (rgba) {
-  const colour = color(rgba);
-  this.options.background = [
-    colour.red(),
-    colour.green(),
-    colour.blue(),
-    Math.round(colour.alpha() * 255)
-  ];
+function tint (rgb) {
+  const colour = color(rgb);
+  this.options.tintA = colour.a();
+  this.options.tintB = colour.b();
   return this;
 }
 
@@ -62,16 +54,62 @@ function grayscale (grayscale) {
   return this.greyscale(grayscale);
 }
 
+/**
+ * Set the pipeline colourspace.
+ *
+ * The input image will be converted to the provided colourspace at the start of the pipeline.
+ * All operations will use this colourspace before converting to the output colourspace, as defined by {@link toColourspace}.
+ *
+ * This feature is experimental and has not yet been fully-tested with all operations.
+ *
+ * @since 0.29.0
+ *
+ * @example
+ * // Run pipeline in 16 bits per channel RGB while converting final result to 8 bits per channel sRGB.
+ * await sharp(input)
+ *  .pipelineColourspace('rgb16')
+ *  .toColourspace('srgb')
+ *  .toFile('16bpc-pipeline-to-8bpc-output.png')
+ *
+ * @param {string} [colourspace] - pipeline colourspace e.g. `rgb16`, `scrgb`, `lab`, `grey16` [...](https://github.com/libvips/libvips/blob/41cff4e9d0838498487a00623462204eb10ee5b8/libvips/iofuncs/enumtypes.c#L774)
+ * @returns {Sharp}
+ * @throws {Error} Invalid parameters
+ */
+function pipelineColourspace (colourspace) {
+  if (!is.string(colourspace)) {
+    throw is.invalidParameterError('colourspace', 'string', colourspace);
+  }
+  this.options.colourspaceInput = colourspace;
+  return this;
+}
+
+/**
+ * Alternative spelling of `pipelineColourspace`.
+ * @param {string} [colorspace] - pipeline colorspace.
+ * @returns {Sharp}
+ * @throws {Error} Invalid parameters
+ */
+function pipelineColorspace (colorspace) {
+  return this.pipelineColourspace(colorspace);
+}
+
 /**
  * Set the output colourspace.
  * By default output image will be web-friendly sRGB, with additional channels interpreted as alpha channels.
- * @param {String} [colourspace] - output colourspace e.g. `srgb`, `rgb`, `cmyk`, `lab`, `b-w` [...](https://github.com/jcupitt/libvips/blob/master/libvips/iofuncs/enumtypes.c#L568)
+ *
+ * @example
+ * // Output 16 bits per pixel RGB
+ * await sharp(input)
+ *  .toColourspace('rgb16')
+ *  .toFile('16-bpp.png')
+ *
+ * @param {string} [colourspace] - output colourspace e.g. `srgb`, `rgb`, `cmyk`, `lab`, `b-w` [...](https://github.com/libvips/libvips/blob/3c0bfdf74ce1dc37a6429bed47fa76f16e2cd70a/libvips/iofuncs/enumtypes.c#L777-L794)
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
  */
 function toColourspace (colourspace) {
   if (!is.string(colourspace)) {
-    throw new Error('Invalid output colourspace ' + colourspace);
+    throw is.invalidParameterError('colourspace', 'string', colourspace);
   }
   this.options.colourspace = colourspace;
   return this;
@@ -79,7 +117,7 @@ function toColourspace (colourspace) {
 
 /**
  * Alternative spelling of `toColourspace`.
- * @param {String} [colorspace] - output colorspace.
+ * @param {string} [colorspace] - output colorspace.
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
  */
@@ -87,20 +125,45 @@ function toColorspace (colorspace) {
   return this.toColourspace(colorspace);
 }
 
+/**
+ * Update a colour attribute of the this.options Object.
+ * @private
+ * @param {string} key
+ * @param {string|Object} value
+ * @throws {Error} Invalid value
+ */
+function _setBackgroundColourOption (key, value) {
+  if (is.defined(value)) {
+    if (is.object(value) || is.string(value)) {
+      const colour = color(value);
+      this.options[key] = [
+        colour.red(),
+        colour.green(),
+        colour.blue(),
+        Math.round(colour.alpha() * 255)
+      ];
+    } else {
+      throw is.invalidParameterError('background', 'object or string', value);
+    }
+  }
+}
+
 /**
  * Decorate the Sharp prototype with colour-related functions.
  * @private
  */
 module.exports = function (Sharp) {
-  // Public instance functions
-  [
-    background,
+  Object.assign(Sharp.prototype, {
+    // Public
+    tint,
     greyscale,
     grayscale,
+    pipelineColourspace,
+    pipelineColorspace,
     toColourspace,
-    toColorspace
-  ].forEach(function (f) {
-    Sharp.prototype[f.name] = f;
+    toColorspace,
+    // Private
+    _setBackgroundColourOption
   });
   // Class attributes
   Sharp.colourspace = colourspace;

lib/composite.js

@@ -3,24 +3,67 @@
 const is = require('./is');
 
 /**
- * Overlay (composite) an image over the processed (resized, extracted etc.) image.
+ * Blend modes.
+ * @member
+ * @private
+ */
+const blend = {
+  clear: 'clear',
+  source: 'source',
+  over: 'over',
+  in: 'in',
+  out: 'out',
+  atop: 'atop',
+  dest: 'dest',
+  'dest-over': 'dest-over',
+  'dest-in': 'dest-in',
+  'dest-out': 'dest-out',
+  'dest-atop': 'dest-atop',
+  xor: 'xor',
+  add: 'add',
+  saturate: 'saturate',
+  multiply: 'multiply',
+  screen: 'screen',
+  overlay: 'overlay',
+  darken: 'darken',
+  lighten: 'lighten',
+  'colour-dodge': 'colour-dodge',
+  'color-dodge': 'colour-dodge',
+  'colour-burn': 'colour-burn',
+  'color-burn': 'colour-burn',
+  'hard-light': 'hard-light',
+  'soft-light': 'soft-light',
+  difference: 'difference',
+  exclusion: 'exclusion'
+};
+
+/**
+ * Composite image(s) over the processed (resized, extracted etc.) image.
  *
- * The overlay image must be the same size or smaller than the processed image.
+ * The images to composite must be the same size or smaller than the processed image.
  * If both `top` and `left` options are provided, they take precedence over `gravity`.
  *
- * If the overlay image contains an alpha channel then composition with premultiplication will occur.
+ * The `blend` option can be one of `clear`, `source`, `over`, `in`, `out`, `atop`,
+ * `dest`, `dest-over`, `dest-in`, `dest-out`, `dest-atop`,
+ * `xor`, `add`, `saturate`, `multiply`, `screen`, `overlay`, `darken`, `lighten`,
+ * `colour-dodge`, `color-dodge`, `colour-burn`,`color-burn`,
+ * `hard-light`, `soft-light`, `difference`, `exclusion`.
+ *
+ * More information about blend modes can be found at
+ * https://libvips.github.io/libvips/API/current/libvips-conversion.html#VipsBlendMode
+ * and https://www.cairographics.org/operators/
+ *
+ * @since 0.22.0
  *
  * @example
  * sharp('input.png')
  *   .rotate(180)
  *   .resize(300)
- *   .flatten()
- *   .background('#ff6600')
- *   .overlayWith('overlay.png', { gravity: sharp.gravity.southeast } )
+ *   .flatten( { background: '#ff6600' } )
+ *   .composite([{ input: 'overlay.png', gravity: 'southeast' }])
  *   .sharpen()
  *   .withMetadata()
- *   .quality(90)
- *   .webp()
+ *   .webp( { quality: 90 } )
  *   .toBuffer()
  *   .then(function(outputBuffer) {
  *     // outputBuffer contains upside down, 300px wide, alpha channel flattened
@@ -28,63 +71,100 @@ const is = require('./is');
  *     // sharpened, with metadata, 90% quality WebP image data. Phew!
  *   });
  *
- * @param {(Buffer|String)} overlay - Buffer containing image data or String containing the path to an image file.
- * @param {Object} [options]
- * @param {String} [options.gravity='centre'] - gravity at which to place the overlay.
- * @param {Number} [options.top] - the pixel offset from the top edge.
- * @param {Number} [options.left] - the pixel offset from the left edge.
- * @param {Boolean} [options.tile=false] - set to true to repeat the overlay image across the entire image with the given `gravity`.
- * @param {Boolean} [options.cutout=false] - set to true to apply only the alpha channel of the overlay image to the input image, giving the appearance of one image being cut out of another.
- * @param {Number} [options.density=72] - integral number representing the DPI for vector overlay image.
- * @param {Object} [options.raw] - describes overlay when using raw pixel data.
- * @param {Number} [options.raw.width]
- * @param {Number} [options.raw.height]
- * @param {Number} [options.raw.channels]
- * @param {Object} [options.create] - describes a blank overlay to be created.
- * @param {Number} [options.create.width]
- * @param {Number} [options.create.height]
- * @param {Number} [options.create.channels] - 3-4
- * @param {String|Object} [options.create.background] - parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
+ * @param {Object[]} images - Ordered list of images to composite
+ * @param {Buffer|String} [images[].input] - Buffer containing image data, String containing the path to an image file, or Create object (see below)
+ * @param {Object} [images[].input.create] - describes a blank overlay to be created.
+ * @param {Number} [images[].input.create.width]
+ * @param {Number} [images[].input.create.height]
+ * @param {Number} [images[].input.create.channels] - 3-4
+ * @param {String|Object} [images[].input.create.background] - parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
+ * @param {String} [images[].blend='over'] - how to blend this image with the image below.
+ * @param {String} [images[].gravity='centre'] - gravity at which to place the overlay.
+ * @param {Number} [images[].top] - the pixel offset from the top edge.
+ * @param {Number} [images[].left] - the pixel offset from the left edge.
+ * @param {Boolean} [images[].tile=false] - set to true to repeat the overlay image across the entire image with the given `gravity`.
+ * @param {Boolean} [images[].premultiplied=false] - set to true to avoid premultipling the image below. Equivalent to the `--premultiplied` vips option.
+ * @param {Number} [images[].density=72] - number representing the DPI for vector overlay image.
+ * @param {Object} [images[].raw] - describes overlay when using raw pixel data.
+ * @param {Number} [images[].raw.width]
+ * @param {Number} [images[].raw.height]
+ * @param {Number} [images[].raw.channels]
+ * @param {boolean} [images[].failOnError=true] - @see {@link /api-constructor#parameters|constructor parameters}
+ * @param {number|boolean} [images[].limitInputPixels=268402689] - @see {@link /api-constructor#parameters|constructor parameters}
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
  */
-function overlayWith (overlay, options) {
-  this.options.overlay = this._createInputDescriptor(overlay, options, {
-    allowStream: false
-  });
-  if (is.object(options)) {
-    if (is.defined(options.tile)) {
-      if (is.bool(options.tile)) {
-        this.options.overlayTile = options.tile;
-      } else {
-        throw new Error('Invalid overlay tile ' + options.tile);
-      }
-    }
-    if (is.defined(options.cutout)) {
-      if (is.bool(options.cutout)) {
-        this.options.overlayCutout = options.cutout;
-      } else {
-        throw new Error('Invalid overlay cutout ' + options.cutout);
-      }
-    }
-    if (is.defined(options.left) || is.defined(options.top)) {
-      if (is.integer(options.left) && options.left >= 0 && is.integer(options.top) && options.top >= 0) {
-        this.options.overlayXOffset = options.left;
-        this.options.overlayYOffset = options.top;
-      } else {
-        throw new Error('Invalid overlay left ' + options.left + ' and/or top ' + options.top);
-      }
-    }
-    if (is.defined(options.gravity)) {
-      if (is.integer(options.gravity) && is.inRange(options.gravity, 0, 8)) {
-        this.options.overlayGravity = options.gravity;
-      } else if (is.string(options.gravity) && is.integer(this.constructor.gravity[options.gravity])) {
-        this.options.overlayGravity = this.constructor.gravity[options.gravity];
-      } else {
-        throw new Error('Unsupported overlay gravity ' + options.gravity);
-      }
-    }
+function composite (images) {
+  if (!Array.isArray(images)) {
+    throw is.invalidParameterError('images to composite', 'array', images);
   }
+  this.options.composite = images.map(image => {
+    if (!is.object(image)) {
+      throw is.invalidParameterError('image to composite', 'object', image);
+    }
+    const inputOptions = this._inputOptionsFromObject(image);
+    const composite = {
+      input: this._createInputDescriptor(image.input, inputOptions, { allowStream: false }),
+      blend: 'over',
+      tile: false,
+      left: 0,
+      top: 0,
+      hasOffset: false,
+      gravity: 0,
+      premultiplied: false
+    };
+    if (is.defined(image.blend)) {
+      if (is.string(blend[image.blend])) {
+        composite.blend = blend[image.blend];
+      } else {
+        throw is.invalidParameterError('blend', 'valid blend name', image.blend);
+      }
+    }
+    if (is.defined(image.tile)) {
+      if (is.bool(image.tile)) {
+        composite.tile = image.tile;
+      } else {
+        throw is.invalidParameterError('tile', 'boolean', image.tile);
+      }
+    }
+    if (is.defined(image.left)) {
+      if (is.integer(image.left)) {
+        composite.left = image.left;
+      } else {
+        throw is.invalidParameterError('left', 'integer', image.left);
+      }
+    }
+    if (is.defined(image.top)) {
+      if (is.integer(image.top)) {
+        composite.top = image.top;
+      } else {
+        throw is.invalidParameterError('top', 'integer', image.top);
+      }
+    }
+    if (is.defined(image.top) !== is.defined(image.left)) {
+      throw new Error('Expected both left and top to be set');
+    } else {
+      composite.hasOffset = is.integer(image.top) && is.integer(image.left);
+    }
+    if (is.defined(image.gravity)) {
+      if (is.integer(image.gravity) && is.inRange(image.gravity, 0, 8)) {
+        composite.gravity = image.gravity;
+      } else if (is.string(image.gravity) && is.integer(this.constructor.gravity[image.gravity])) {
+        composite.gravity = this.constructor.gravity[image.gravity];
+      } else {
+        throw is.invalidParameterError('gravity', 'valid gravity', image.gravity);
+      }
+    }
+    if (is.defined(image.premultiplied)) {
+      if (is.bool(image.premultiplied)) {
+        composite.premultiplied = image.premultiplied;
+      } else {
+        throw is.invalidParameterError('premultiplied', 'boolean', image.premultiplied);
+      }
+    }
+
+    return composite;
+  });
   return this;
 }
 
@@ -93,5 +173,6 @@ function overlayWith (overlay, options) {
  * @private
  */
 module.exports = function (Sharp) {
-  Sharp.prototype.overlayWith = overlayWith;
+  Sharp.prototype.composite = composite;
+  Sharp.blend = blend;
 };

lib/constructor.js

@@ -1,59 +1,30 @@
 'use strict';
 
-const path = require('path');
 const util = require('util');
 const stream = require('stream');
-const events = require('events');
-const semver = require('semver');
 const is = require('./is');
-const platform = require('./platform');
-const sharp = require('../build/Release/sharp.node');
 
-// Vendor platform
-(function () {
-  let vendorPlatformId;
-  try {
-    vendorPlatformId = require('../vendor/platform.json');
-  } catch (err) {
-    return;
-  }
-  const currentPlatformId = platform();
-  /* istanbul ignore if */
-  if (currentPlatformId !== vendorPlatformId) {
-    throw new Error(`'${vendorPlatformId}' binaries cannot be used on the '${currentPlatformId}' platform. Please remove the 'node_modules/sharp/vendor' directory and run 'npm rebuild'.`);
-  }
-})();
-
-// Versioning
-let versions = {
-  vips: sharp.libvipsVersion()
-};
-(function () {
-  // Does libvips meet minimum requirement?
-  const libvipsVersionMin = require('../package.json').config.libvips;
-  /* istanbul ignore if */
-  if (semver.lt(versions.vips, libvipsVersionMin)) {
-    throw new Error('Found libvips ' + versions.vips + ' but require at least ' + libvipsVersionMin);
-  }
-  // Include versions of dependencies, if present
-  try {
-    versions = require('../vendor/versions.json');
-  } catch (err) {}
-})();
+require('./libvips').hasVendoredLibvips();
+require('./sharp');
 
 // Use NODE_DEBUG=sharp to enable libvips warnings
 const debuglog = util.debuglog('sharp');
 
 /**
- * @class Sharp
- *
  * Constructor factory to create an instance of `sharp`, to which further methods are chained.
  *
- * JPEG, PNG, WebP or TIFF format image data can be streamed out from this object.
+ * JPEG, PNG, WebP, AVIF or TIFF format image data can be streamed out from this object.
  * When using Stream based output, derived attributes are available from the `info` event.
  *
+ * Non-critical problems encountered during processing are emitted as `warning` events.
+ *
  * Implements the [stream.Duplex](http://nodejs.org/api/stream.html#stream_class_stream_duplex) class.
  *
+ * @constructs Sharp
+ *
+ * @emits Sharp#info
+ * @emits Sharp#warning
+ *
  * @example
  * sharp('input.jpg')
  *   .resize(300, 200)
@@ -81,31 +52,80 @@ const debuglog = util.debuglog('sharp');
  *     width: 300,
  *     height: 200,
  *     channels: 4,
- *     background: { r: 255, g: 0, b: 0, alpha: 128 }
+ *     background: { r: 255, g: 0, b: 0, alpha: 0.5 }
  *   }
  * })
  * .png()
  * .toBuffer()
  * .then( ... );
  *
- * @param {(Buffer|String)} [input] - if present, can be
- *  a Buffer containing JPEG, PNG, WebP, GIF, SVG, TIFF or raw pixel image data, or
- *  a String containing the path to an JPEG, PNG, WebP, GIF, SVG or TIFF image file.
- *  JPEG, PNG, WebP, GIF, SVG, TIFF or raw pixel image data can be streamed into the object when not present.
+ * @example
+ * // Convert an animated GIF to an animated WebP
+ * await sharp('in.gif', { animated: true }).toFile('out.webp');
+ *
+ * @example
+ * // Read a raw array of pixels and save it to a png
+ * const input = Uint8Array.from([255, 255, 255, 0, 0, 0]); // or Uint8ClampedArray
+ * const image = sharp(input, {
+ *   // because the input does not contain its dimensions or how many channels it has
+ *   // we need to specify it in the constructor options
+ *   raw: {
+ *     width: 2,
+ *     height: 1,
+ *     channels: 3
+ *   }
+ * });
+ * await image.toFile('my-two-pixels.png');
+ *
+ * @example
+ * // Generate RGB Gaussian noise
+ * await sharp({
+ *   create: {
+ *     width: 300,
+ *     height: 200,
+ *     channels: 3,
+ *     noise: {
+ *       type: 'gaussian',
+ *       mean: 128,
+ *       sigma: 30
+ *     }
+ *  }
+ * }).toFile('noise.png');
+ *
+ * @param {(Buffer|Uint8Array|Uint8ClampedArray|Int8Array|Uint16Array|Int16Array|Uint32Array|Int32Array|Float32Array|Float64Array|string)} [input] - if present, can be
+ *  a Buffer / Uint8Array / Uint8ClampedArray containing JPEG, PNG, WebP, AVIF, GIF, SVG or TIFF image data, or
+ *  a TypedArray containing raw pixel image data, or
+ *  a String containing the filesystem path to an JPEG, PNG, WebP, AVIF, GIF, SVG or TIFF image file.
+ *  JPEG, PNG, WebP, AVIF, GIF, SVG, TIFF or raw pixel image data can be streamed into the object when not present.
  * @param {Object} [options] - if present, is an Object with optional attributes.
- * @param {Boolean} [options.failOnError=false] - by default apply a "best effort"
- *  to decode images, even if the data is corrupt or invalid. Set this flag to true
- *  if you'd rather halt processing and raise an error when loading invalid images.
- * @param {Number} [options.density=72] - integral number representing the DPI for vector images.
+ * @param {boolean} [options.failOnError=true] - by default halt processing and raise an error when loading invalid images.
+ *  Set this flag to `false` if you'd rather apply a "best effort" to decode images, even if the data is corrupt or invalid.
+ * @param {number|boolean} [options.limitInputPixels=268402689] - Do not process input images where the number of pixels
+ *  (width x height) exceeds this limit. Assumes image dimensions contained in the input metadata can be trusted.
+ *  An integral Number of pixels, zero or false to remove limit, true to use default limit of 268402689 (0x3FFF x 0x3FFF).
+ * @param {boolean} [options.sequentialRead=false] - Set this to `true` to use sequential rather than random access where possible.
+ *  This can reduce memory usage and might improve performance on some systems.
+ * @param {number} [options.density=72] - number representing the DPI for vector images in the range 1 to 100000.
+ * @param {number} [options.pages=1] - number of pages to extract for multi-page input (GIF, WebP, AVIF, TIFF, PDF), use -1 for all pages.
+ * @param {number} [options.page=0] - page number to start extracting from for multi-page input (GIF, WebP, AVIF, TIFF, PDF), zero based.
+ * @param {number} [options.subifd=-1] - subIFD (Sub Image File Directory) to extract for OME-TIFF, defaults to main image.
+ * @param {number} [options.level=0] - level to extract from a multi-level input (OpenSlide), zero based.
+ * @param {boolean} [options.animated=false] - Set to `true` to read all frames/pages of an animated image (equivalent of setting `pages` to `-1`).
  * @param {Object} [options.raw] - describes raw pixel input image data. See `raw()` for pixel ordering.
- * @param {Number} [options.raw.width]
- * @param {Number} [options.raw.height]
- * @param {Number} [options.raw.channels] - 1-4
+ * @param {number} [options.raw.width] - integral number of pixels wide.
+ * @param {number} [options.raw.height] - integral number of pixels high.
+ * @param {number} [options.raw.channels] - integral number of channels, between 1 and 4.
+ * @param {boolean} [options.raw.premultiplied] - specifies that the raw input has already been premultiplied, set to `true`
+ *  to avoid sharp premultiplying the image. (optional, default `false`)
  * @param {Object} [options.create] - describes a new image to be created.
- * @param {Number} [options.create.width]
- * @param {Number} [options.create.height]
- * @param {Number} [options.create.channels] - 3-4
- * @param {String|Object} [options.create.background] - parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
+ * @param {number} [options.create.width] - integral number of pixels wide.
+ * @param {number} [options.create.height] - integral number of pixels high.
+ * @param {number} [options.create.channels] - integral number of channels, either 3 (RGB) or 4 (RGBA).
+ * @param {string|Object} [options.create.background] - parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
+ * @param {Object} [options.create.noise] - describes a noise to be created.
+ * @param {string} [options.create.noise.type] - type of generated noise, currently only `gaussian` is supported.
+ * @param {number} [options.create.noise.mean] - mean of pixels in generated noise.
+ * @param {number} [options.create.noise.sigma] - standard deviation of pixels in generated noise.
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
  */
@@ -118,11 +138,6 @@ const Sharp = function (input, options) {
   }
   stream.Duplex.call(this);
   this.options = {
-    // input options
-    sequentialRead: false,
-    limitInputPixels: Math.pow(0x3FFF, 2),
-    // ICC profiles
-    iccProfilePath: path.join(__dirname, 'icc') + path.sep,
     // resize options
     topOffsetPre: -1,
     leftOffsetPre: -1,
@@ -135,10 +150,12 @@ const Sharp = function (input, options) {
     width: -1,
     height: -1,
     canvas: 'crop',
-    crop: 0,
-    embed: 0,
+    position: 0,
+    resizeBackground: [0, 0, 0, 255],
     useExifOrientation: false,
     angle: 0,
+    rotationAngle: 0,
+    rotationBackground: [0, 0, 0, 255],
     rotateBeforePreExtract: false,
     flip: false,
     flop: false,
@@ -146,40 +163,61 @@ const Sharp = function (input, options) {
     extendBottom: 0,
     extendLeft: 0,
     extendRight: 0,
+    extendBackground: [0, 0, 0, 255],
     withoutEnlargement: false,
+    affineMatrix: [],
+    affineBackground: [0, 0, 0, 255],
+    affineIdx: 0,
+    affineIdy: 0,
+    affineOdx: 0,
+    affineOdy: 0,
+    affineInterpolator: this.constructor.interpolators.bilinear,
     kernel: 'lanczos3',
     fastShrinkOnLoad: true,
     // operations
-    background: [0, 0, 0, 255],
+    tintA: 128,
+    tintB: 128,
     flatten: false,
+    flattenBackground: [0, 0, 0],
     negate: false,
+    negateAlpha: true,
+    medianSize: 0,
     blurSigma: 0,
     sharpenSigma: 0,
     sharpenFlat: 1,
     sharpenJagged: 2,
     threshold: 0,
     thresholdGrayscale: true,
-    trimTolerance: 0,
+    trimThreshold: 0,
     gamma: 0,
+    gammaOut: 0,
     greyscale: false,
-    normalise: 0,
+    normalise: false,
+    claheWidth: 0,
+    claheHeight: 0,
+    claheMaxSlope: 3,
+    brightness: 1,
+    saturation: 1,
+    hue: 0,
+    lightness: 0,
     booleanBufferIn: null,
     booleanFileIn: '',
     joinChannelIn: [],
     extractChannel: -1,
+    removeAlpha: false,
+    ensureAlpha: -1,
     colourspace: 'srgb',
-    // overlay
-    overlayGravity: 0,
-    overlayXOffset: -1,
-    overlayYOffset: -1,
-    overlayTile: false,
-    overlayCutout: false,
+    colourspaceInput: 'last',
+    composite: [],
     // output
     fileOut: '',
     formatOut: 'input',
     streamOut: false,
     withMetadata: false,
     withMetadataOrientation: -1,
+    withMetadataDensity: 0,
+    withMetadataIcc: '',
+    withMetadataStrs: {},
     resolveWithObject: false,
     // output format
     jpegQuality: 80,
@@ -188,63 +226,151 @@ const Sharp = function (input, options) {
     jpegTrellisQuantisation: false,
     jpegOvershootDeringing: false,
     jpegOptimiseScans: false,
+    jpegOptimiseCoding: true,
+    jpegQuantisationTable: 0,
     pngProgressive: false,
-    pngCompressionLevel: 9,
+    pngCompressionLevel: 6,
     pngAdaptiveFiltering: false,
+    pngPalette: false,
+    pngQuality: 100,
+    pngBitdepth: 8,
+    pngDither: 1,
+    jp2Quality: 80,
+    jp2TileHeight: 512,
+    jp2TileWidth: 512,
+    jp2Lossless: false,
+    jp2ChromaSubsampling: '4:4:4',
     webpQuality: 80,
     webpAlphaQuality: 100,
     webpLossless: false,
     webpNearLossless: false,
+    webpSmartSubsample: false,
+    webpReductionEffort: 4,
     tiffQuality: 80,
     tiffCompression: 'jpeg',
     tiffPredictor: 'horizontal',
-    tiffSquash: false,
+    tiffPyramid: false,
+    tiffBitdepth: 8,
+    tiffTile: false,
+    tiffTileHeight: 256,
+    tiffTileWidth: 256,
     tiffXres: 1.0,
     tiffYres: 1.0,
+    heifQuality: 50,
+    heifLossless: false,
+    heifCompression: 'av1',
+    heifSpeed: 5,
+    heifChromaSubsampling: '4:4:4',
+    rawDepth: 'uchar',
     tileSize: 256,
     tileOverlap: 0,
+    tileContainer: 'fs',
+    tileLayout: 'dz',
+    tileFormat: 'last',
+    tileDepth: 'last',
+    tileAngle: 0,
+    tileSkipBlanks: -1,
+    tileBackground: [255, 255, 255, 255],
+    tileCentre: false,
+    tileId: 'https://example.com/iiif',
+    timeoutSeconds: 0,
     linearA: 1,
     linearB: 0,
     // Function to notify of libvips warnings
-    debuglog: debuglog,
+    debuglog: warning => {
+      this.emit('warning', warning);
+      debuglog(warning);
+    },
     // Function to notify of queue length changes
     queueListener: function (queueLength) {
-      queue.emit('change', queueLength);
+      Sharp.queue.emit('change', queueLength);
     }
   };
   this.options.input = this._createInputDescriptor(input, options, { allowStream: true });
   return this;
 };
-util.inherits(Sharp, stream.Duplex);
+Object.setPrototypeOf(Sharp.prototype, stream.Duplex.prototype);
+Object.setPrototypeOf(Sharp, stream.Duplex);
 
 /**
- * An EventEmitter that emits a `change` event when a task is either:
- * - queued, waiting for _libuv_ to provide a worker thread
- * - complete
- * @member
+ * Take a "snapshot" of the Sharp instance, returning a new instance.
+ * Cloned instances inherit the input of their parent instance.
+ * This allows multiple output Streams and therefore multiple processing pipelines to share a single input Stream.
+ *
  * @example
- * sharp.queue.on('change', function(queueLength) {
- *   console.log('Queue contains ' + queueLength + ' task(s)');
+ * const pipeline = sharp().rotate();
+ * pipeline.clone().resize(800, 600).pipe(firstWritableStream);
+ * pipeline.clone().extract({ left: 20, top: 20, width: 100, height: 100 }).pipe(secondWritableStream);
+ * readableStream.pipe(pipeline);
+ * // firstWritableStream receives auto-rotated, resized readableStream
+ * // secondWritableStream receives auto-rotated, extracted region of readableStream
+ *
+ * @example
+ * // Create a pipeline that will download an image, resize it and format it to different files
+ * // Using Promises to know when the pipeline is complete
+ * const fs = require("fs");
+ * const got = require("got");
+ * const sharpStream = sharp({
+ *   failOnError: false
  * });
+ *
+ * const promises = [];
+ *
+ * promises.push(
+ *   sharpStream
+ *     .clone()
+ *     .jpeg({ quality: 100 })
+ *     .toFile("originalFile.jpg")
+ * );
+ *
+ * promises.push(
+ *   sharpStream
+ *     .clone()
+ *     .resize({ width: 500 })
+ *     .jpeg({ quality: 80 })
+ *     .toFile("optimized-500.jpg")
+ * );
+ *
+ * promises.push(
+ *   sharpStream
+ *     .clone()
+ *     .resize({ width: 500 })
+ *     .webp({ quality: 80 })
+ *     .toFile("optimized-500.webp")
+ * );
+ *
+ * // https://github.com/sindresorhus/got#gotstreamurl-options
+ * got.stream("https://www.example.com/some-file.jpg").pipe(sharpStream);
+ *
+ * Promise.all(promises)
+ *   .then(res => { console.log("Done!", res); })
+ *   .catch(err => {
+ *     console.error("Error processing files, let's clean it up", err);
+ *     try {
+ *       fs.unlinkSync("originalFile.jpg");
+ *       fs.unlinkSync("optimized-500.jpg");
+ *       fs.unlinkSync("optimized-500.webp");
+ *     } catch (e) {}
+ *   });
+ *
+ * @returns {Sharp}
  */
-const queue = new events.EventEmitter();
-Sharp.queue = queue;
-
-/**
- * An Object containing nested boolean values representing the available input and output formats/methods.
- * @example
- * console.log(sharp.format);
- * @returns {Object}
- */
-Sharp.format = sharp.format();
-
-/**
- * An Object containing the version numbers of libvips and its dependencies.
- * @member
- * @example
- * console.log(sharp.versions);
- */
-Sharp.versions = versions;
+function clone () {
+  // Clone existing options
+  const clone = this.constructor.call();
+  clone.options = Object.assign({}, this.options);
+  // Pass 'finish' event to clone for Stream-based input
+  if (this._isStreamInput()) {
+    this.on('finish', () => {
+      // Clone inherits input data
+      this._flattenBufferIn();
+      clone.options.bufferIn = this.options.bufferIn;
+      clone.emit('finish');
+    });
+  }
+  return clone;
+}
+Object.assign(Sharp.prototype, { clone });
 
 /**
  * Export constructor.

lib/input.js

@@ -2,28 +2,57 @@
 
 const color = require('color');
 const is = require('./is');
-const sharp = require('../build/Release/sharp.node');
+const sharp = require('./sharp');
+
+/**
+ * Extract input options, if any, from an object.
+ * @private
+ */
+function _inputOptionsFromObject (obj) {
+  const { raw, density, limitInputPixels, sequentialRead, failOnError, animated, page, pages, subifd } = obj;
+  return [raw, density, limitInputPixels, sequentialRead, failOnError, animated, page, pages, subifd].some(is.defined)
+    ? { raw, density, limitInputPixels, sequentialRead, failOnError, animated, page, pages, subifd }
+    : undefined;
+}
 
 /**
  * Create Object containing input and input-related options.
  * @private
  */
 function _createInputDescriptor (input, inputOptions, containerOptions) {
-  const inputDescriptor = { failOnError: false };
+  const inputDescriptor = {
+    failOnError: true,
+    limitInputPixels: Math.pow(0x3FFF, 2),
+    sequentialRead: false
+  };
   if (is.string(input)) {
     // filesystem
     inputDescriptor.file = input;
   } else if (is.buffer(input)) {
     // Buffer
+    if (input.length === 0) {
+      throw Error('Input Buffer is empty');
+    }
     inputDescriptor.buffer = input;
+  } else if (is.typedArray(input)) {
+    if (input.length === 0) {
+      throw Error('Input Bit Array is empty');
+    }
+    inputDescriptor.buffer = Buffer.from(input.buffer);
   } else if (is.plainObject(input) && !is.defined(inputOptions)) {
     // Plain Object descriptor, e.g. create
     inputOptions = input;
-  } else if (!is.defined(input) && is.object(containerOptions) && containerOptions.allowStream) {
-    // Stream
+    if (_inputOptionsFromObject(inputOptions)) {
+      // Stream with options
+      inputDescriptor.buffer = [];
+    }
+  } else if (!is.defined(input) && !is.defined(inputOptions) && is.object(containerOptions) && containerOptions.allowStream) {
+    // Stream without options
     inputDescriptor.buffer = [];
   } else {
-    throw new Error('Unsupported input ' + typeof input);
+    throw new Error(`Unsupported input '${input}' of type ${typeof input}${
+      is.defined(inputOptions) ? ` when also providing options of type ${typeof inputOptions}` : ''
+    }`);
   }
   if (is.object(inputOptions)) {
     // Fail on error
@@ -31,15 +60,35 @@ function _createInputDescriptor (input, inputOptions, containerOptions) {
       if (is.bool(inputOptions.failOnError)) {
         inputDescriptor.failOnError = inputOptions.failOnError;
       } else {
-        throw new Error('Invalid failOnError (boolean) ' + inputOptions.failOnError);
+        throw is.invalidParameterError('failOnError', 'boolean', inputOptions.failOnError);
       }
     }
     // Density
     if (is.defined(inputOptions.density)) {
-      if (is.integer(inputOptions.density) && is.inRange(inputOptions.density, 1, 2400)) {
+      if (is.inRange(inputOptions.density, 1, 100000)) {
         inputDescriptor.density = inputOptions.density;
       } else {
-        throw new Error('Invalid density (1 to 2400) ' + inputOptions.density);
+        throw is.invalidParameterError('density', 'number between 1 and 100000', inputOptions.density);
+      }
+    }
+    // limitInputPixels
+    if (is.defined(inputOptions.limitInputPixels)) {
+      if (is.bool(inputOptions.limitInputPixels)) {
+        inputDescriptor.limitInputPixels = inputOptions.limitInputPixels
+          ? Math.pow(0x3FFF, 2)
+          : 0;
+      } else if (is.integer(inputOptions.limitInputPixels) && inputOptions.limitInputPixels >= 0) {
+        inputDescriptor.limitInputPixels = inputOptions.limitInputPixels;
+      } else {
+        throw is.invalidParameterError('limitInputPixels', 'integer >= 0', inputOptions.limitInputPixels);
+      }
+    }
+    // sequentialRead
+    if (is.defined(inputOptions.sequentialRead)) {
+      if (is.bool(inputOptions.sequentialRead)) {
+        inputDescriptor.sequentialRead = inputOptions.sequentialRead;
+      } else {
+        throw is.invalidParameterError('sequentialRead', 'boolean', inputOptions.sequentialRead);
       }
     }
     // Raw pixel input
@@ -53,32 +102,130 @@ function _createInputDescriptor (input, inputOptions, containerOptions) {
         inputDescriptor.rawWidth = inputOptions.raw.width;
         inputDescriptor.rawHeight = inputOptions.raw.height;
         inputDescriptor.rawChannels = inputOptions.raw.channels;
+        inputDescriptor.rawPremultiplied = !!inputOptions.raw.premultiplied;
+
+        switch (input.constructor) {
+          case Uint8Array:
+          case Uint8ClampedArray:
+            inputDescriptor.rawDepth = 'uchar';
+            break;
+          case Int8Array:
+            inputDescriptor.rawDepth = 'char';
+            break;
+          case Uint16Array:
+            inputDescriptor.rawDepth = 'ushort';
+            break;
+          case Int16Array:
+            inputDescriptor.rawDepth = 'short';
+            break;
+          case Uint32Array:
+            inputDescriptor.rawDepth = 'uint';
+            break;
+          case Int32Array:
+            inputDescriptor.rawDepth = 'int';
+            break;
+          case Float32Array:
+            inputDescriptor.rawDepth = 'float';
+            break;
+          case Float64Array:
+            inputDescriptor.rawDepth = 'double';
+            break;
+          default:
+            inputDescriptor.rawDepth = 'uchar';
+            break;
+        }
       } else {
         throw new Error('Expected width, height and channels for raw pixel input');
       }
     }
+    // Multi-page input (GIF, TIFF, PDF)
+    if (is.defined(inputOptions.animated)) {
+      if (is.bool(inputOptions.animated)) {
+        inputDescriptor.pages = inputOptions.animated ? -1 : 1;
+      } else {
+        throw is.invalidParameterError('animated', 'boolean', inputOptions.animated);
+      }
+    }
+    if (is.defined(inputOptions.pages)) {
+      if (is.integer(inputOptions.pages) && is.inRange(inputOptions.pages, -1, 100000)) {
+        inputDescriptor.pages = inputOptions.pages;
+      } else {
+        throw is.invalidParameterError('pages', 'integer between -1 and 100000', inputOptions.pages);
+      }
+    }
+    if (is.defined(inputOptions.page)) {
+      if (is.integer(inputOptions.page) && is.inRange(inputOptions.page, 0, 100000)) {
+        inputDescriptor.page = inputOptions.page;
+      } else {
+        throw is.invalidParameterError('page', 'integer between 0 and 100000', inputOptions.page);
+      }
+    }
+    // Multi-level input (OpenSlide)
+    if (is.defined(inputOptions.level)) {
+      if (is.integer(inputOptions.level) && is.inRange(inputOptions.level, 0, 256)) {
+        inputDescriptor.level = inputOptions.level;
+      } else {
+        throw is.invalidParameterError('level', 'integer between 0 and 256', inputOptions.level);
+      }
+    }
+    // Sub Image File Directory (TIFF)
+    if (is.defined(inputOptions.subifd)) {
+      if (is.integer(inputOptions.subifd) && is.inRange(inputOptions.subifd, -1, 100000)) {
+        inputDescriptor.subifd = inputOptions.subifd;
+      } else {
+        throw is.invalidParameterError('subifd', 'integer between -1 and 100000', inputOptions.subifd);
+      }
+    }
     // Create new image
     if (is.defined(inputOptions.create)) {
       if (
         is.object(inputOptions.create) &&
         is.integer(inputOptions.create.width) && inputOptions.create.width > 0 &&
         is.integer(inputOptions.create.height) && inputOptions.create.height > 0 &&
-        is.integer(inputOptions.create.channels) && is.inRange(inputOptions.create.channels, 3, 4) &&
-        is.defined(inputOptions.create.background)
+        is.integer(inputOptions.create.channels)
       ) {
         inputDescriptor.createWidth = inputOptions.create.width;
         inputDescriptor.createHeight = inputOptions.create.height;
         inputDescriptor.createChannels = inputOptions.create.channels;
-        const background = color(inputOptions.create.background);
-        inputDescriptor.createBackground = [
-          background.red(),
-          background.green(),
-          background.blue(),
-          Math.round(background.alpha() * 255)
-        ];
+        // Noise
+        if (is.defined(inputOptions.create.noise)) {
+          if (!is.object(inputOptions.create.noise)) {
+            throw new Error('Expected noise to be an object');
+          }
+          if (!is.inArray(inputOptions.create.noise.type, ['gaussian'])) {
+            throw new Error('Only gaussian noise is supported at the moment');
+          }
+          if (!is.inRange(inputOptions.create.channels, 1, 4)) {
+            throw is.invalidParameterError('create.channels', 'number between 1 and 4', inputOptions.create.channels);
+          }
+          inputDescriptor.createNoiseType = inputOptions.create.noise.type;
+          if (is.number(inputOptions.create.noise.mean) && is.inRange(inputOptions.create.noise.mean, 0, 10000)) {
+            inputDescriptor.createNoiseMean = inputOptions.create.noise.mean;
+          } else {
+            throw is.invalidParameterError('create.noise.mean', 'number between 0 and 10000', inputOptions.create.noise.mean);
+          }
+          if (is.number(inputOptions.create.noise.sigma) && is.inRange(inputOptions.create.noise.sigma, 0, 10000)) {
+            inputDescriptor.createNoiseSigma = inputOptions.create.noise.sigma;
+          } else {
+            throw is.invalidParameterError('create.noise.sigma', 'number between 0 and 10000', inputOptions.create.noise.sigma);
+          }
+        } else if (is.defined(inputOptions.create.background)) {
+          if (!is.inRange(inputOptions.create.channels, 3, 4)) {
+            throw is.invalidParameterError('create.channels', 'number between 3 and 4', inputOptions.create.channels);
+          }
+          const background = color(inputOptions.create.background);
+          inputDescriptor.createBackground = [
+            background.red(),
+            background.green(),
+            background.blue(),
+            Math.round(background.alpha() * 255)
+          ];
+        } else {
+          throw new Error('Expected valid noise or background to create a new input image');
+        }
         delete inputDescriptor.buffer;
       } else {
-        throw new Error('Expected width, height, channels and background to create a new input image');
+        throw new Error('Expected valid width, height and channels to create a new input image');
       }
     }
   } else if (is.defined(inputOptions)) {
@@ -91,7 +238,7 @@ function _createInputDescriptor (input, inputOptions, containerOptions) {
  * Handle incoming Buffer chunk on Writable Stream.
  * @private
  * @param {Buffer} chunk
- * @param {String} encoding - unused
+ * @param {string} encoding - unused
  * @param {Function} callback
  */
 function _write (chunk, encoding, callback) {
@@ -100,9 +247,8 @@ function _write (chunk, encoding, callback) {
     /* istanbul ignore else */
     if (is.buffer(chunk)) {
       if (this.options.input.buffer.length === 0) {
-        const that = this;
-        this.on('finish', function () {
-          that.streamInFinished = true;
+        this.on('finish', () => {
+          this.streamInFinished = true;
         });
       }
       this.options.input.buffer.push(chunk);
@@ -128,55 +274,35 @@ function _flattenBufferIn () {
 /**
  * Are we expecting Stream-based input?
  * @private
- * @returns {Boolean}
+ * @returns {boolean}
  */
 function _isStreamInput () {
   return Array.isArray(this.options.input.buffer);
 }
 
-/**
- * Take a "snapshot" of the Sharp instance, returning a new instance.
- * Cloned instances inherit the input of their parent instance.
- * This allows multiple output Streams and therefore multiple processing pipelines to share a single input Stream.
- *
- * @example
- * const pipeline = sharp().rotate();
- * pipeline.clone().resize(800, 600).pipe(firstWritableStream);
- * pipeline.clone().extract({ left: 20, top: 20, width: 100, height: 100 }).pipe(secondWritableStream);
- * readableStream.pipe(pipeline);
- * // firstWritableStream receives auto-rotated, resized readableStream
- * // secondWritableStream receives auto-rotated, extracted region of readableStream
- *
- * @returns {Sharp}
- */
-function clone () {
-  const that = this;
-  // Clone existing options
-  const clone = this.constructor.call();
-  clone.options = Object.assign({}, this.options);
-  // Pass 'finish' event to clone for Stream-based input
-  if (this._isStreamInput()) {
-    this.on('finish', function () {
-      // Clone inherits input data
-      that._flattenBufferIn();
-      clone.options.bufferIn = that.options.bufferIn;
-      clone.emit('finish');
-    });
-  }
-  return clone;
-}
-
 /**
  * Fast access to (uncached) image metadata without decoding any compressed image data.
- * A Promises/A+ promise is returned when `callback` is not provided.
+ * A `Promise` is returned when `callback` is not provided.
  *
  * - `format`: Name of decoder used to decompress image data e.g. `jpeg`, `png`, `webp`, `gif`, `svg`
- * - `width`: Number of pixels wide
- * - `height`: Number of pixels high
- * - `space`: Name of colour space interpretation e.g. `srgb`, `rgb`, `cmyk`, `lab`, `b-w` [...](https://github.com/jcupitt/libvips/blob/master/libvips/iofuncs/enumtypes.c#L636)
+ * - `size`: Total size of image in bytes, for Stream and Buffer input only
+ * - `width`: Number of pixels wide (EXIF orientation is not taken into consideration)
+ * - `height`: Number of pixels high (EXIF orientation is not taken into consideration)
+ * - `space`: Name of colour space interpretation e.g. `srgb`, `rgb`, `cmyk`, `lab`, `b-w` [...](https://libvips.github.io/libvips/API/current/VipsImage.html#VipsInterpretation)
  * - `channels`: Number of bands e.g. `3` for sRGB, `4` for CMYK
- * - `depth`: Name of pixel depth format e.g. `uchar`, `char`, `ushort`, `float` [...](https://github.com/jcupitt/libvips/blob/master/libvips/iofuncs/enumtypes.c#L672)
+ * - `depth`: Name of pixel depth format e.g. `uchar`, `char`, `ushort`, `float` [...](https://libvips.github.io/libvips/API/current/VipsImage.html#VipsBandFormat)
  * - `density`: Number of pixels per inch (DPI), if present
+ * - `chromaSubsampling`: String containing JPEG chroma subsampling, `4:2:0` or `4:4:4` for RGB, `4:2:0:4` or `4:4:4:4` for CMYK
+ * - `isProgressive`: Boolean indicating whether the image is interlaced using a progressive scan
+ * - `pages`: Number of pages/frames contained within the image, with support for TIFF, HEIF, PDF, animated GIF and animated WebP
+ * - `pageHeight`: Number of pixels high each page in a multi-page image will be.
+ * - `loop`: Number of times to loop an animated image, zero refers to a continuous loop.
+ * - `delay`: Delay in ms between each page in an animated image, provided as an array of integers.
+ * - `pagePrimary`: Number of the primary page in a HEIF image
+ * - `levels`: Details of each level in a multi-level image provided as an array of objects, requires libvips compiled with support for OpenSlide
+ * - `subifds`: Number of Sub Image File Directories in an OME-TIFF image
+ * - `background`: Default background colour, if present, for PNG (bKGD) and GIF images, either an RGB Object or a single greyscale value
+ * - `compression`: The encoder used to compress an HEIF file, `av1` (AVIF) or `hevc` (HEIC)
  * - `hasProfile`: Boolean indicating the presence of an embedded ICC profile
  * - `hasAlpha`: Boolean indicating the presence of an alpha transparency channel
  * - `orientation`: Number value of the EXIF Orientation header, if present
@@ -184,6 +310,7 @@ function clone () {
  * - `icc`: Buffer containing raw [ICC](https://www.npmjs.com/package/icc) profile data, if present
  * - `iptc`: Buffer containing raw IPTC data, if present
  * - `xmp`: Buffer containing raw XMP data, if present
+ * - `tifftagPhotoshop`: Buffer containing raw TIFFTAG_PHOTOSHOP data, if present
  *
  * @example
  * const image = sharp(inputJpg);
@@ -203,12 +330,11 @@ function clone () {
  * @returns {Promise<Object>|Sharp}
  */
 function metadata (callback) {
-  const that = this;
   if (is.fn(callback)) {
     if (this._isStreamInput()) {
-      this.on('finish', function () {
-        that._flattenBufferIn();
-        sharp.metadata(that.options, callback);
+      this.on('finish', () => {
+        this._flattenBufferIn();
+        sharp.metadata(this.options, callback);
       });
     } else {
       sharp.metadata(this.options, callback);
@@ -216,10 +342,10 @@ function metadata (callback) {
     return this;
   } else {
     if (this._isStreamInput()) {
-      return new Promise(function (resolve, reject) {
-        that.on('finish', function () {
-          that._flattenBufferIn();
-          sharp.metadata(that.options, function (err, metadata) {
+      return new Promise((resolve, reject) => {
+        this.on('finish', () => {
+          this._flattenBufferIn();
+          sharp.metadata(this.options, (err, metadata) => {
             if (err) {
               reject(err);
             } else {
@@ -229,8 +355,8 @@ function metadata (callback) {
         });
       });
     } else {
-      return new Promise(function (resolve, reject) {
-        sharp.metadata(that.options, function (err, metadata) {
+      return new Promise((resolve, reject) => {
+        sharp.metadata(this.options, (err, metadata) => {
           if (err) {
             reject(err);
           } else {
@@ -244,7 +370,7 @@ function metadata (callback) {
 
 /**
  * Access to pixel-derived image statistics for every channel in the image.
- * A Promise is returned when `callback` is not provided.
+ * A `Promise` is returned when `callback` is not provided.
  *
  * - `channels`: Array of channel statistics for each channel in the image. Each channel statistic contains
  *     - `min` (minimum value in the channel)
@@ -257,7 +383,13 @@ function metadata (callback) {
  *     - `minY` (y-coordinate of one of the pixel where the minimum lies)
  *     - `maxX` (x-coordinate of one of the pixel where the maximum lies)
  *     - `maxY` (y-coordinate of one of the pixel where the maximum lies)
- * - `isOpaque`: Value to identify if the image is opaque or transparent, based on the presence and use of alpha channel
+ * - `isOpaque`: Is the image fully opaque? Will be `true` if the image has no alpha channel or if every pixel is fully opaque.
+ * - `entropy`: Histogram-based estimation of greyscale entropy, discarding alpha channel if any (experimental)
+ * - `sharpness`: Estimation of greyscale sharpness based on the standard deviation of a Laplacian convolution, discarding alpha channel if any (experimental)
+ * - `dominant`: Object containing most dominant sRGB colour based on a 4096-bin 3D histogram (experimental)
+ *
+ * **Note**: Statistics are derived from the original input image. Any operations performed on the image must first be
+ * written to a buffer in order to run `stats` on the result (see third example).
  *
  * @example
  * const image = sharp(inputJpg);
@@ -267,16 +399,26 @@ function metadata (callback) {
  *      // stats contains the channel-wise statistics array and the isOpaque value
  *   });
  *
+ * @example
+ * const { entropy, sharpness, dominant } = await sharp(input).stats();
+ * const { r, g, b } = dominant;
+ *
+ * @example
+ * const image = sharp(input);
+ * // store intermediate result
+ * const part = await image.extract(region).toBuffer();
+ * // create new instance to obtain statistics of extracted region
+ * const stats = await sharp(part).stats();
+ *
  * @param {Function} [callback] - called with the arguments `(err, stats)`
  * @returns {Promise<Object>}
  */
 function stats (callback) {
-  const that = this;
   if (is.fn(callback)) {
     if (this._isStreamInput()) {
-      this.on('finish', function () {
-        that._flattenBufferIn();
-        sharp.stats(that.options, callback);
+      this.on('finish', () => {
+        this._flattenBufferIn();
+        sharp.stats(this.options, callback);
       });
     } else {
       sharp.stats(this.options, callback);
@@ -284,10 +426,10 @@ function stats (callback) {
     return this;
   } else {
     if (this._isStreamInput()) {
-      return new Promise(function (resolve, reject) {
-        that.on('finish', function () {
-          that._flattenBufferIn();
-          sharp.stats(that.options, function (err, stats) {
+      return new Promise((resolve, reject) => {
+        this.on('finish', function () {
+          this._flattenBufferIn();
+          sharp.stats(this.options, (err, stats) => {
             if (err) {
               reject(err);
             } else {
@@ -297,8 +439,8 @@ function stats (callback) {
         });
       });
     } else {
-      return new Promise(function (resolve, reject) {
-        sharp.stats(that.options, function (err, stats) {
+      return new Promise((resolve, reject) => {
+        sharp.stats(this.options, (err, stats) => {
           if (err) {
             reject(err);
           } else {
@@ -310,61 +452,20 @@ function stats (callback) {
   }
 }
 
-/**
- * Do not process input images where the number of pixels (width * height) exceeds this limit.
- * Assumes image dimensions contained in the input metadata can be trusted.
- * The default limit is 268402689 (0x3FFF * 0x3FFF) pixels.
- * @param {(Number|Boolean)} limit - an integral Number of pixels, zero or false to remove limit, true to use default limit.
- * @returns {Sharp}
- * @throws {Error} Invalid limit
-*/
-function limitInputPixels (limit) {
-  // if we pass in false we represent the integer as 0 to disable
-  if (limit === false) {
-    limit = 0;
-  } else if (limit === true) {
-    limit = Math.pow(0x3FFF, 2);
-  }
-  if (is.integer(limit) && limit >= 0) {
-    this.options.limitInputPixels = limit;
-  } else {
-    throw is.invalidParameterError('limitInputPixels', 'integer', limit);
-  }
-  return this;
-}
-
-/**
- * An advanced setting that switches the libvips access method to `VIPS_ACCESS_SEQUENTIAL`.
- * This will reduce memory usage and can improve performance on some systems.
- *
- * The default behaviour *before* function call is `false`, meaning the libvips access method is not sequential.
- *
- * @param {Boolean} [sequentialRead=true]
- * @returns {Sharp}
- */
-function sequentialRead (sequentialRead) {
-  this.options.sequentialRead = is.bool(sequentialRead) ? sequentialRead : true;
-  return this;
-}
-
 /**
  * Decorate the Sharp prototype with input-related functions.
  * @private
  */
 module.exports = function (Sharp) {
-  [
+  Object.assign(Sharp.prototype, {
     // Private
+    _inputOptionsFromObject,
     _createInputDescriptor,
     _write,
     _flattenBufferIn,
     _isStreamInput,
     // Public
-    clone,
     metadata,
-    stats,
-    limitInputPixels,
-    sequentialRead
-  ].forEach(function (f) {
-    Sharp.prototype[f.name] = f;
+    stats
   });
 };

lib/is.js

@@ -21,7 +21,7 @@ const object = function (val) {
  * @private
  */
 const plainObject = function (val) {
-  return object(val) && Object.prototype.toString.call(val) === '[object Object]';
+  return Object.prototype.toString.call(val) === '[object Object]';
 };
 
 /**
@@ -45,7 +45,30 @@ const bool = function (val) {
  * @private
  */
 const buffer = function (val) {
-  return object(val) && val instanceof Buffer;
+  return val instanceof Buffer;
+};
+
+/**
+ * Is this value a typed array object?. E.g. Uint8Array or Uint8ClampedArray?
+ * @private
+ */
+const typedArray = function (val) {
+  if (defined(val)) {
+    switch (val.constructor) {
+      case Uint8Array:
+      case Uint8ClampedArray:
+      case Int8Array:
+      case Uint16Array:
+      case Int16Array:
+      case Uint32Array:
+      case Int32Array:
+      case Float32Array:
+      case Float64Array:
+        return true;
+    }
+  }
+
+  return false;
 };
 
 /**
@@ -69,7 +92,7 @@ const number = function (val) {
  * @private
  */
 const integer = function (val) {
-  return number(val) && val % 1 === 0;
+  return Number.isInteger(val);
 };
 
 /**
@@ -85,14 +108,14 @@ const inRange = function (val, min, max) {
  * @private
  */
 const inArray = function (val, list) {
-  return list.indexOf(val) !== -1;
+  return list.includes(val);
 };
 
 /**
  * Create an Error with a message relating to an invalid parameter.
  *
- * @param {String} name - parameter name.
- * @param {String} expected - description of the type/value/range expected.
+ * @param {string} name - parameter name.
+ * @param {string} expected - description of the type/value/range expected.
  * @param {*} actual - the value received.
  * @returns {Error} Containing the formatted message.
  * @private
@@ -110,6 +133,7 @@ module.exports = {
   fn: fn,
   bool: bool,
   buffer: buffer,
+  typedArray: typedArray,
   string: string,
   number: number,
   integer: integer,

lib/libvips.js

@@ -0,0 +1,108 @@
+'use strict';
+
+const fs = require('fs');
+const os = require('os');
+const path = require('path');
+const spawnSync = require('child_process').spawnSync;
+const semverCoerce = require('semver/functions/coerce');
+const semverGreaterThanOrEqualTo = require('semver/functions/gte');
+
+const platform = require('./platform');
+
+const env = process.env;
+const minimumLibvipsVersionLabelled = env.npm_package_config_libvips || /* istanbul ignore next */
+  require('../package.json').config.libvips;
+const minimumLibvipsVersion = semverCoerce(minimumLibvipsVersionLabelled).version;
+
+const spawnSyncOptions = {
+  encoding: 'utf8',
+  shell: true
+};
+
+const mkdirSync = function (dirPath) {
+  try {
+    fs.mkdirSync(dirPath, { recursive: true });
+  } catch (err) {
+    /* istanbul ignore next */
+    if (err.code !== 'EEXIST') {
+      throw err;
+    }
+  }
+};
+
+const cachePath = function () {
+  const npmCachePath = env.npm_config_cache || /* istanbul ignore next */
+    (env.APPDATA ? path.join(env.APPDATA, 'npm-cache') : path.join(os.homedir(), '.npm'));
+  mkdirSync(npmCachePath);
+  const libvipsCachePath = path.join(npmCachePath, '_libvips');
+  mkdirSync(libvipsCachePath);
+  return libvipsCachePath;
+};
+
+const log = function (item) {
+  if (item instanceof Error) {
+    console.error(`sharp: Installation error: ${item.message}`);
+  } else {
+    console.log(`sharp: ${item}`);
+  }
+};
+
+const isRosetta = function () {
+  /* istanbul ignore next */
+  if (process.platform === 'darwin' && process.arch === 'x64') {
+    const translated = spawnSync('sysctl sysctl.proc_translated', spawnSyncOptions).stdout;
+    return (translated || '').trim() === 'sysctl.proc_translated: 1';
+  }
+  return false;
+};
+
+const globalLibvipsVersion = function () {
+  if (process.platform !== 'win32') {
+    const globalLibvipsVersion = spawnSync(`PKG_CONFIG_PATH="${pkgConfigPath()}" pkg-config --modversion vips-cpp`, spawnSyncOptions).stdout;
+    /* istanbul ignore next */
+    return (globalLibvipsVersion || '').trim();
+  } else {
+    return '';
+  }
+};
+
+const hasVendoredLibvips = function () {
+  const vendorPath = path.join(__dirname, '..', 'vendor', minimumLibvipsVersion, platform());
+  return fs.existsSync(vendorPath);
+};
+
+const pkgConfigPath = function () {
+  if (process.platform !== 'win32') {
+    const brewPkgConfigPath = spawnSync('which brew >/dev/null 2>&1 && eval $(brew --env) && echo $PKG_CONFIG_LIBDIR', spawnSyncOptions).stdout || '';
+    return [brewPkgConfigPath.trim(), env.PKG_CONFIG_PATH, '/usr/local/lib/pkgconfig', '/usr/lib/pkgconfig']
+      .filter(function (p) { return !!p; })
+      .join(':');
+  } else {
+    return '';
+  }
+};
+
+const useGlobalLibvips = function () {
+  if (Boolean(env.SHARP_IGNORE_GLOBAL_LIBVIPS) === true) {
+    return false;
+  }
+  /* istanbul ignore next */
+  if (isRosetta()) {
+    return false;
+  }
+  const globalVipsVersion = globalLibvipsVersion();
+  return !!globalVipsVersion && /* istanbul ignore next */
+    semverGreaterThanOrEqualTo(globalVipsVersion, minimumLibvipsVersion);
+};
+
+module.exports = {
+  minimumLibvipsVersion,
+  minimumLibvipsVersionLabelled,
+  cachePath,
+  log,
+  globalLibvipsVersion,
+  hasVendoredLibvips,
+  pkgConfigPath,
+  useGlobalLibvips,
+  mkdirSync
+};

lib/operation.js

@@ -1,14 +1,18 @@
 'use strict';
 
+const color = require('color');
 const is = require('./is');
 
 /**
  * Rotate the output image by either an explicit angle
  * or auto-orient based on the EXIF `Orientation` tag.
  *
- * If an angle is provided, it is converted to a valid 90/180/270deg rotation.
+ * If an angle is provided, it is converted to a valid positive degree rotation.
  * For example, `-450` will produce a 270deg rotation.
  *
+ * When rotating by an angle other than a multiple of 90,
+ * the background colour can be provided with the `background` option.
+ *
  * If no angle is provided, it is determined from the EXIF data.
  * Mirroring is supported and may infer the use of a flip operation.
  *
@@ -28,64 +32,30 @@ const is = require('./is');
  *   });
  * readableStream.pipe(pipeline);
  *
- * @param {Number} [angle=auto] angle of rotation, must be a multiple of 90.
+ * @param {number} [angle=auto] angle of rotation.
+ * @param {Object} [options] - if present, is an Object with optional attributes.
+ * @param {string|Object} [options.background="#000000"] parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
  */
-function rotate (angle) {
+function rotate (angle, options) {
   if (!is.defined(angle)) {
     this.options.useExifOrientation = true;
   } else if (is.integer(angle) && !(angle % 90)) {
     this.options.angle = angle;
-  } else {
-    throw new Error('Unsupported angle: angle must be a positive/negative multiple of 90 ' + angle);
-  }
-  return this;
-}
-
-/**
- * Extract a region of the image.
- *
- * - Use `extract` before `resize` for pre-resize extraction.
- * - Use `extract` after `resize` for post-resize extraction.
- * - Use `extract` before and after for both.
- *
- * @example
- * sharp(input)
- *   .extract({ left: left, top: top, width: width, height: height })
- *   .toFile(output, function(err) {
- *     // Extract a region of the input image, saving in the same format.
- *   });
- * @example
- * sharp(input)
- *   .extract({ left: leftOffsetPre, top: topOffsetPre, width: widthPre, height: heightPre })
- *   .resize(width, height)
- *   .extract({ left: leftOffsetPost, top: topOffsetPost, width: widthPost, height: heightPost })
- *   .toFile(output, function(err) {
- *     // Extract a region, resize, then extract from the resized image
- *   });
- *
- * @param {Object} options
- * @param {Number} options.left - zero-indexed offset from left edge
- * @param {Number} options.top - zero-indexed offset from top edge
- * @param {Number} options.width - dimension of extracted image
- * @param {Number} options.height - dimension of extracted image
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
-function extract (options) {
-  const suffix = this.options.width === -1 && this.options.height === -1 ? 'Pre' : 'Post';
-  ['left', 'top', 'width', 'height'].forEach(function (name) {
-    const value = options[name];
-    if (is.integer(value) && value >= 0) {
-      this.options[name + (name === 'left' || name === 'top' ? 'Offset' : '') + suffix] = value;
-    } else {
-      throw new Error('Non-integer value for ' + name + ' of ' + value);
+  } else if (is.number(angle)) {
+    this.options.rotationAngle = angle;
+    if (is.object(options) && options.background) {
+      const backgroundColour = color(options.background);
+      this.options.rotationBackground = [
+        backgroundColour.red(),
+        backgroundColour.green(),
+        backgroundColour.blue(),
+        Math.round(backgroundColour.alpha() * 255)
+      ];
     }
-  }, this);
-  // Ensure existing rotation occurs before pre-resize extraction
-  if (suffix === 'Pre' && ((this.options.angle % 360) !== 0 || this.options.useExifOrientation === true)) {
-    this.options.rotateBeforePreExtract = true;
+  } else {
+    throw is.invalidParameterError('angle', 'numeric', angle);
   }
   return this;
 }
@@ -112,15 +82,112 @@ function flop (flop) {
   return this;
 }
 
+/**
+ * Perform an affine transform on an image. This operation will always occur after resizing, extraction and rotation, if any.
+ *
+ * You must provide an array of length 4 or a 2x2 affine transformation matrix.
+ * By default, new pixels are filled with a black background. You can provide a background color with the `background` option.
+ * A particular interpolator may also be specified. Set the `interpolator` option to an attribute of the `sharp.interpolator` Object e.g. `sharp.interpolator.nohalo`.
+ *
+ * In the case of a 2x2 matrix, the transform is:
+ * - X = `matrix[0, 0]` \* (x + `idx`) + `matrix[0, 1]` \* (y + `idy`) + `odx`
+ * - Y = `matrix[1, 0]` \* (x + `idx`) + `matrix[1, 1]` \* (y + `idy`) + `ody`
+ *
+ * where:
+ * - x and y are the coordinates in input image.
+ * - X and Y are the coordinates in output image.
+ * - (0,0) is the upper left corner.
+ *
+ * @since 0.27.0
+ *
+ * @example
+ * const pipeline = sharp()
+ *   .affine([[1, 0.3], [0.1, 0.7]], {
+ *      background: 'white',
+ *      interpolate: sharp.interpolators.nohalo
+ *   })
+ *   .toBuffer((err, outputBuffer, info) => {
+ *      // outputBuffer contains the transformed image
+ *      // info.width and info.height contain the new dimensions
+ *   });
+ *
+ * inputStream
+ *   .pipe(pipeline);
+ *
+ * @param {Array<Array<number>>|Array<number>} matrix - affine transformation matrix
+ * @param {Object} [options] - if present, is an Object with optional attributes.
+ * @param {String|Object} [options.background="#000000"] - parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
+ * @param {Number} [options.idx=0] - input horizontal offset
+ * @param {Number} [options.idy=0] - input vertical offset
+ * @param {Number} [options.odx=0] - output horizontal offset
+ * @param {Number} [options.ody=0] - output vertical offset
+ * @param {String} [options.interpolator=sharp.interpolators.bicubic] - interpolator
+ * @returns {Sharp}
+ * @throws {Error} Invalid parameters
+ */
+function affine (matrix, options) {
+  const flatMatrix = [].concat(...matrix);
+  if (flatMatrix.length === 4 && flatMatrix.every(is.number)) {
+    this.options.affineMatrix = flatMatrix;
+  } else {
+    throw is.invalidParameterError('matrix', '1x4 or 2x2 array', matrix);
+  }
+
+  if (is.defined(options)) {
+    if (is.object(options)) {
+      this._setBackgroundColourOption('affineBackground', options.background);
+      if (is.defined(options.idx)) {
+        if (is.number(options.idx)) {
+          this.options.affineIdx = options.idx;
+        } else {
+          throw is.invalidParameterError('options.idx', 'number', options.idx);
+        }
+      }
+      if (is.defined(options.idy)) {
+        if (is.number(options.idy)) {
+          this.options.affineIdy = options.idy;
+        } else {
+          throw is.invalidParameterError('options.idy', 'number', options.idy);
+        }
+      }
+      if (is.defined(options.odx)) {
+        if (is.number(options.odx)) {
+          this.options.affineOdx = options.odx;
+        } else {
+          throw is.invalidParameterError('options.odx', 'number', options.odx);
+        }
+      }
+      if (is.defined(options.ody)) {
+        if (is.number(options.ody)) {
+          this.options.affineOdy = options.ody;
+        } else {
+          throw is.invalidParameterError('options.ody', 'number', options.ody);
+        }
+      }
+      if (is.defined(options.interpolator)) {
+        if (is.inArray(options.interpolator, Object.values(this.constructor.interpolators))) {
+          this.options.affineInterpolator = options.interpolator;
+        } else {
+          throw is.invalidParameterError('options.interpolator', 'valid interpolator name', options.interpolator);
+        }
+      }
+    } else {
+      throw is.invalidParameterError('options', 'object', options);
+    }
+  }
+
+  return this;
+}
+
 /**
  * Sharpen the image.
  * When used without parameters, performs a fast, mild sharpen of the output image.
  * When a `sigma` is provided, performs a slower, more accurate sharpen of the L channel in the LAB colour space.
  * Separate control over the level of sharpening in "flat" and "jagged" areas is available.
  *
- * @param {Number} [sigma] - the sigma of the Gaussian mask, where `sigma = 1 + radius / 2`.
- * @param {Number} [flat=1.0] - the level of sharpening to apply to "flat" areas.
- * @param {Number} [jagged=2.0] - the level of sharpening to apply to "jagged" areas.
+ * @param {number} [sigma] - the sigma of the Gaussian mask, where `sigma = 1 + radius / 2`.
+ * @param {number} [flat=1.0] - the level of sharpening to apply to "flat" areas.
+ * @param {number} [jagged=2.0] - the level of sharpening to apply to "jagged" areas.
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
  */
@@ -139,7 +206,7 @@ function sharpen (sigma, flat, jagged) {
       if (is.number(flat) && is.inRange(flat, 0, 10000)) {
         this.options.sharpenFlat = flat;
       } else {
-        throw new Error('Invalid sharpen level for flat areas (0.0 - 10000.0) ' + flat);
+        throw is.invalidParameterError('flat', 'number between 0 and 10000', flat);
       }
     }
     // Control over jagged areas
@@ -147,11 +214,31 @@ function sharpen (sigma, flat, jagged) {
       if (is.number(jagged) && is.inRange(jagged, 0, 10000)) {
         this.options.sharpenJagged = jagged;
       } else {
-        throw new Error('Invalid sharpen level for jagged areas (0.0 - 10000.0) ' + jagged);
+        throw is.invalidParameterError('jagged', 'number between 0 and 10000', jagged);
       }
     }
   } else {
-    throw new Error('Invalid sharpen sigma (0.01 - 10000) ' + sigma);
+    throw is.invalidParameterError('sigma', 'number between 0.01 and 10000', sigma);
+  }
+  return this;
+}
+
+/**
+ * Apply median filter.
+ * When used without parameters the default window is 3x3.
+ * @param {number} [size=3] square mask size: size x size
+ * @returns {Sharp}
+ * @throws {Error} Invalid parameters
+ */
+function median (size) {
+  if (!is.defined(size)) {
+    // No arguments: default to 3x3
+    this.options.medianSize = 3;
+  } else if (is.integer(size) && is.inRange(size, 1, 1000)) {
+    // Numeric argument: specific sigma
+    this.options.medianSize = size;
+  } else {
+    throw is.invalidParameterError('size', 'integer between 1 and 1000', size);
   }
   return this;
 }
@@ -160,7 +247,7 @@ function sharpen (sigma, flat, jagged) {
  * Blur the image.
  * When used without parameters, performs a fast, mild blur of the output image.
  * When a `sigma` is provided, performs a slower, more accurate Gaussian blur.
- * @param {Number} [sigma] a value between 0.3 and 1000 representing the sigma of the Gaussian mask, where `sigma = 1 + radius / 2`.
+ * @param {number} [sigma] a value between 0.3 and 1000 representing the sigma of the Gaussian mask, where `sigma = 1 + radius / 2`.
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
  */
@@ -175,78 +262,29 @@ function blur (sigma) {
     // Numeric argument: specific sigma
     this.options.blurSigma = sigma;
   } else {
-    throw new Error('Invalid blur sigma (0.3 - 1000.0) ' + sigma);
+    throw is.invalidParameterError('sigma', 'number between 0.3 and 1000', sigma);
   }
   return this;
 }
 
 /**
- * Extends/pads the edges of the image with the colour provided to the `background` method.
- * This operation will always occur after resizing and extraction, if any.
+ * Merge alpha transparency channel, if any, with a background, then remove the alpha channel.
+ *
+ * See also {@link /api-channel#removealpha|removeAlpha}.
  *
  * @example
- * // Resize to 140 pixels wide, then add 10 transparent pixels
- * // to the top, left and right edges and 20 to the bottom edge
- * sharp(input)
- *   .resize(140)
- *   .background({r: 0, g: 0, b: 0, alpha: 0})
- *   .extend({top: 10, bottom: 20, left: 10, right: 10})
- *   ...
+ * await sharp(rgbaInput)
+ *   .flatten({ background: '#F0A703' })
+ *   .toBuffer();
  *
- * @param {(Number|Object)} extend - single pixel count to add to all edges or an Object with per-edge counts
- * @param {Number} [extend.top]
- * @param {Number} [extend.left]
- * @param {Number} [extend.bottom]
- * @param {Number} [extend.right]
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
-*/
-function extend (extend) {
-  if (is.integer(extend) && extend > 0) {
-    this.options.extendTop = extend;
-    this.options.extendBottom = extend;
-    this.options.extendLeft = extend;
-    this.options.extendRight = extend;
-  } else if (
-    is.object(extend) &&
-    is.integer(extend.top) && extend.top >= 0 &&
-    is.integer(extend.bottom) && extend.bottom >= 0 &&
-    is.integer(extend.left) && extend.left >= 0 &&
-    is.integer(extend.right) && extend.right >= 0
-  ) {
-    this.options.extendTop = extend.top;
-    this.options.extendBottom = extend.bottom;
-    this.options.extendLeft = extend.left;
-    this.options.extendRight = extend.right;
-  } else {
-    throw new Error('Invalid edge extension ' + extend);
-  }
-  return this;
-}
-
-/**
- * Merge alpha transparency channel, if any, with `background`.
- * @param {Boolean} [flatten=true]
+ * @param {Object} [options]
+ * @param {string|Object} [options.background={r: 0, g: 0, b: 0}] - background colour, parsed by the [color](https://www.npmjs.org/package/color) module, defaults to black.
  * @returns {Sharp}
  */
-function flatten (flatten) {
-  this.options.flatten = is.bool(flatten) ? flatten : true;
-  return this;
-}
-
-/**
- * Trim "boring" pixels from all edges that contain values within a percentage similarity of the top-left pixel.
- * @param {Number} [tolerance=10] value between 1 and 99 representing the percentage similarity.
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
-function trim (tolerance) {
-  if (!is.defined(tolerance)) {
-    this.options.trimTolerance = 10;
-  } else if (is.integer(tolerance) && is.inRange(tolerance, 1, 99)) {
-    this.options.trimTolerance = tolerance;
-  } else {
-    throw new Error('Invalid trim tolerance (1 to 99) ' + tolerance);
+function flatten (options) {
+  this.options.flatten = is.bool(options) ? options : true;
+  if (is.object(options)) {
+    this._setBackgroundColourOption('flattenBackground', options.background);
   }
   return this;
 }
@@ -257,29 +295,49 @@ function trim (tolerance) {
  * This can improve the perceived brightness of a resized image in non-linear colour spaces.
  * JPEG and WebP input images will not take advantage of the shrink-on-load performance optimisation
  * when applying a gamma correction.
- * @param {Number} [gamma=2.2] value between 1.0 and 3.0.
+ *
+ * Supply a second argument to use a different output gamma value, otherwise the first value is used in both cases.
+ *
+ * @param {number} [gamma=2.2] value between 1.0 and 3.0.
+ * @param {number} [gammaOut] value between 1.0 and 3.0. (optional, defaults to same as `gamma`)
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
  */
-function gamma (gamma) {
+function gamma (gamma, gammaOut) {
   if (!is.defined(gamma)) {
     // Default gamma correction of 2.2 (sRGB)
     this.options.gamma = 2.2;
   } else if (is.number(gamma) && is.inRange(gamma, 1, 3)) {
     this.options.gamma = gamma;
   } else {
-    throw new Error('Invalid gamma correction (1.0 to 3.0) ' + gamma);
+    throw is.invalidParameterError('gamma', 'number between 1.0 and 3.0', gamma);
+  }
+  if (!is.defined(gammaOut)) {
+    // Default gamma correction for output is same as input
+    this.options.gammaOut = this.options.gamma;
+  } else if (is.number(gammaOut) && is.inRange(gammaOut, 1, 3)) {
+    this.options.gammaOut = gammaOut;
+  } else {
+    throw is.invalidParameterError('gammaOut', 'number between 1.0 and 3.0', gammaOut);
   }
   return this;
 }
 
 /**
  * Produce the "negative" of the image.
- * @param {Boolean} [negate=true]
+ * @param {Object} [options]
+ * @param {Boolean} [options.alpha=true] Whether or not to negate any alpha channel
  * @returns {Sharp}
  */
-function negate (negate) {
-  this.options.negate = is.bool(negate) ? negate : true;
+function negate (options) {
+  this.options.negate = is.bool(options) ? options : true;
+  if (is.plainObject(options) && 'alpha' in options) {
+    if (!is.bool(options.alpha)) {
+      throw is.invalidParameterError('alpha', 'should be boolean value', options.alpha);
+    } else {
+      this.options.negateAlpha = options.alpha;
+    }
+  }
   return this;
 }
 
@@ -302,6 +360,47 @@ function normalize (normalize) {
   return this.normalise(normalize);
 }
 
+/**
+ * Perform contrast limiting adaptive histogram equalization
+ * {@link https://en.wikipedia.org/wiki/Adaptive_histogram_equalization#Contrast_Limited_AHE|CLAHE}.
+ *
+ * This will, in general, enhance the clarity of the image by bringing out darker details.
+ *
+ * @since 0.28.3
+ *
+ * @param {Object} options
+ * @param {number} options.width - integer width of the region in pixels.
+ * @param {number} options.height - integer height of the region in pixels.
+ * @param {number} [options.maxSlope=3] - maximum value for the slope of the
+ *  cumulative histogram. A value of 0 disables contrast limiting. Valid values
+ *  are integers in the range 0-100 (inclusive)
+ * @returns {Sharp}
+ * @throws {Error} Invalid parameters
+ */
+function clahe (options) {
+  if (!is.plainObject(options)) {
+    throw is.invalidParameterError('options', 'plain object', options);
+  }
+  if (!('width' in options) || !is.integer(options.width) || options.width <= 0) {
+    throw is.invalidParameterError('width', 'integer above zero', options.width);
+  } else {
+    this.options.claheWidth = options.width;
+  }
+  if (!('height' in options) || !is.integer(options.height) || options.height <= 0) {
+    throw is.invalidParameterError('height', 'integer above zero', options.height);
+  } else {
+    this.options.claheHeight = options.height;
+  }
+  if (!is.defined(options.maxSlope)) {
+    this.options.claheMaxSlope = 3;
+  } else if (!is.integer(options.maxSlope) || options.maxSlope < 0 || options.maxSlope > 100) {
+    throw is.invalidParameterError('maxSlope', 'integer 0-100', options.maxSlope);
+  } else {
+    this.options.claheMaxSlope = options.maxSlope;
+  }
+  return this;
+}
+
 /**
  * Convolve the image with the specified kernel.
  *
@@ -319,11 +418,11 @@ function normalize (normalize) {
  *   });
  *
  * @param {Object} kernel
- * @param {Number} kernel.width - width of the kernel in pixels.
- * @param {Number} kernel.height - width of the kernel in pixels.
- * @param {Array<Number>} kernel.kernel - Array of length `width*height` containing the kernel values.
- * @param {Number} [kernel.scale=sum] - the scale of the kernel in pixels.
- * @param {Number} [kernel.offset=0] - the offset of the kernel in pixels.
+ * @param {number} kernel.width - width of the kernel in pixels.
+ * @param {number} kernel.height - height of the kernel in pixels.
+ * @param {Array<number>} kernel.kernel - Array of length `width*height` containing the kernel values.
+ * @param {number} [kernel.scale=sum] - the scale of the kernel in pixels.
+ * @param {number} [kernel.offset=0] - the offset of the kernel in pixels.
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
  */
@@ -354,8 +453,8 @@ function convolve (kernel) {
 }
 
 /**
- * Any pixel value greather than or equal to the threshold value will be set to 255, otherwise it will be set to 0.
- * @param {Number} [threshold=128] - a value in the range 0-255 representing the level at which the threshold will be applied.
+ * Any pixel value greater than or equal to the threshold value will be set to 255, otherwise it will be set to 0.
+ * @param {number} [threshold=128] - a value in the range 0-255 representing the level at which the threshold will be applied.
  * @param {Object} [options]
  * @param {Boolean} [options.greyscale=true] - convert to single channel greyscale.
  * @param {Boolean} [options.grayscale=true] - alternative spelling for greyscale.
@@ -370,7 +469,7 @@ function threshold (threshold, options) {
   } else if (is.integer(threshold) && is.inRange(threshold, 0, 255)) {
     this.options.threshold = threshold;
   } else {
-    throw new Error('Invalid threshold (0 to 255) ' + threshold);
+    throw is.invalidParameterError('threshold', 'integer between 0 and 255', threshold);
   }
   if (!is.object(options) || options.greyscale === true || options.grayscale === true) {
     this.options.thresholdGrayscale = true;
@@ -386,13 +485,13 @@ function threshold (threshold, options) {
  * This operation creates an output image where each pixel is the result of
  * the selected bitwise boolean `operation` between the corresponding pixels of the input images.
  *
- * @param {Buffer|String} operand - Buffer containing image data or String containing the path to an image file.
- * @param {String} operator - one of `and`, `or` or `eor` to perform that bitwise operation, like the C logic operators `&`, `|` and `^` respectively.
+ * @param {Buffer|string} operand - Buffer containing image data or string containing the path to an image file.
+ * @param {string} operator - one of `and`, `or` or `eor` to perform that bitwise operation, like the C logic operators `&`, `|` and `^` respectively.
  * @param {Object} [options]
  * @param {Object} [options.raw] - describes operand when using raw pixel data.
- * @param {Number} [options.raw.width]
- * @param {Number} [options.raw.height]
- * @param {Number} [options.raw.channels]
+ * @param {number} [options.raw.width]
+ * @param {number} [options.raw.height]
+ * @param {number} [options.raw.channels]
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
  */
@@ -401,15 +500,15 @@ function boolean (operand, operator, options) {
   if (is.string(operator) && is.inArray(operator, ['and', 'or', 'eor'])) {
     this.options.booleanOp = operator;
   } else {
-    throw new Error('Invalid boolean operator ' + operator);
+    throw is.invalidParameterError('operator', 'one of: and, or, eor', operator);
   }
   return this;
 }
 
 /**
  * Apply the linear formula a * input + b to the image (levels adjustment)
- * @param {Number} [a=1.0] multiplier
- * @param {Number} [b=0.0] offset
+ * @param {number} [a=1.0] multiplier
+ * @param {number} [b=0.0] offset
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
  */
@@ -419,17 +518,127 @@ function linear (a, b) {
   } else if (is.number(a)) {
     this.options.linearA = a;
   } else {
-    throw new Error('Invalid linear transform multiplier ' + a);
+    throw is.invalidParameterError('a', 'numeric', a);
   }
-
   if (!is.defined(b)) {
     this.options.linearB = 0.0;
   } else if (is.number(b)) {
     this.options.linearB = b;
   } else {
-    throw new Error('Invalid linear transform offset ' + b);
+    throw is.invalidParameterError('b', 'numeric', b);
   }
+  return this;
+}
 
+/**
+ * Recomb the image with the specified matrix.
+ *
+ * @since 0.21.1
+ *
+ * @example
+ * sharp(input)
+ *   .recomb([
+ *    [0.3588, 0.7044, 0.1368],
+ *    [0.2990, 0.5870, 0.1140],
+ *    [0.2392, 0.4696, 0.0912],
+ *   ])
+ *   .raw()
+ *   .toBuffer(function(err, data, info) {
+ *     // data contains the raw pixel data after applying the recomb
+ *     // With this example input, a sepia filter has been applied
+ *   });
+ *
+ * @param {Array<Array<number>>} inputMatrix - 3x3 Recombination matrix
+ * @returns {Sharp}
+ * @throws {Error} Invalid parameters
+ */
+function recomb (inputMatrix) {
+  if (!Array.isArray(inputMatrix) || inputMatrix.length !== 3 ||
+      inputMatrix[0].length !== 3 ||
+      inputMatrix[1].length !== 3 ||
+      inputMatrix[2].length !== 3
+  ) {
+    // must pass in a kernel
+    throw new Error('Invalid recombination matrix');
+  }
+  this.options.recombMatrix = [
+    inputMatrix[0][0], inputMatrix[0][1], inputMatrix[0][2],
+    inputMatrix[1][0], inputMatrix[1][1], inputMatrix[1][2],
+    inputMatrix[2][0], inputMatrix[2][1], inputMatrix[2][2]
+  ].map(Number);
+  return this;
+}
+
+/**
+ * Transforms the image using brightness, saturation, hue rotation, and lightness.
+ * Brightness and lightness both operate on luminance, with the difference being that
+ * brightness is multiplicative whereas lightness is additive.
+ *
+ * @since 0.22.1
+ *
+ * @example
+ * sharp(input)
+ *   .modulate({
+ *     brightness: 2 // increase brightness by a factor of 2
+ *   });
+ *
+ * sharp(input)
+ *   .modulate({
+ *     hue: 180 // hue-rotate by 180 degrees
+ *   });
+ *
+ * sharp(input)
+ *   .modulate({
+ *     lightness: 50 // increase lightness by +50
+ *   });
+ *
+ * // decreate brightness and saturation while also hue-rotating by 90 degrees
+ * sharp(input)
+ *   .modulate({
+ *     brightness: 0.5,
+ *     saturation: 0.5,
+ *     hue: 90
+ *   });
+ *
+ * @param {Object} [options]
+ * @param {number} [options.brightness] Brightness multiplier
+ * @param {number} [options.saturation] Saturation multiplier
+ * @param {number} [options.hue] Degrees for hue rotation
+ * @param {number} [options.lightness] Lightness addend
+ * @returns {Sharp}
+ */
+function modulate (options) {
+  if (!is.plainObject(options)) {
+    throw is.invalidParameterError('options', 'plain object', options);
+  }
+  if ('brightness' in options) {
+    if (is.number(options.brightness) && options.brightness >= 0) {
+      this.options.brightness = options.brightness;
+    } else {
+      throw is.invalidParameterError('brightness', 'number above zero', options.brightness);
+    }
+  }
+  if ('saturation' in options) {
+    if (is.number(options.saturation) && options.saturation >= 0) {
+      this.options.saturation = options.saturation;
+    } else {
+      throw is.invalidParameterError('saturation', 'number above zero', options.saturation);
+    }
+  }
+  if ('hue' in options) {
+    if (is.integer(options.hue)) {
+      this.options.hue = options.hue % 360;
+    } else {
+      throw is.invalidParameterError('hue', 'number', options.hue);
+    }
+  }
+  if ('lightness' in options) {
+    if (is.number(options.lightness)) {
+      this.options.lightness = options.lightness;
+    } else {
+      throw is.invalidParameterError('lightness', 'number', options.lightness);
+    }
+  }
   return this;
 }
 
@@ -438,25 +647,25 @@ function linear (a, b) {
  * @private
  */
 module.exports = function (Sharp) {
-  [
+  Object.assign(Sharp.prototype, {
     rotate,
-    extract,
     flip,
     flop,
+    affine,
     sharpen,
+    median,
     blur,
-    extend,
     flatten,
-    trim,
     gamma,
     negate,
     normalise,
     normalize,
+    clahe,
     convolve,
     threshold,
     boolean,
-    linear
-  ].forEach(function (f) {
-    Sharp.prototype[f.name] = f;
+    linear,
+    recomb,
+    modulate
   });
 };

lib/platform.js

@@ -1,15 +1,25 @@
 'use strict';
 
-module.exports = function () {
-  const arch = process.env.npm_config_arch || process.arch;
-  const platform = process.env.npm_config_platform || process.platform;
+const detectLibc = require('detect-libc');
 
-  const platformId = [platform];
-  if (arch === 'arm' || arch === 'armhf' || arch === 'arm64') {
-    const armVersion = (arch === 'arm64') ? '8' : process.env.npm_config_armv || process.config.variables.arm_version || '6';
-    platformId.push(`armv${armVersion}`);
+const env = process.env;
+
+module.exports = function () {
+  const arch = env.npm_config_arch || process.arch;
+  const platform = env.npm_config_platform || process.platform;
+  /* istanbul ignore next */
+  const libc = (platform === 'linux' && detectLibc.isNonGlibcLinux) ? detectLibc.family : '';
+
+  const platformId = [`${platform}${libc}`];
+
+  if (arch === 'arm') {
+    const fallback = process.versions.electron ? '7' : '6';
+    platformId.push(`armv${env.npm_config_arm_version || process.config.variables.arm_version || fallback}`);
+  } else if (arch === 'arm64') {
+    platformId.push(`arm64v${env.npm_config_arm_version || '8'}`);
   } else {
     platformId.push(arch);
   }
+
   return platformId.join('-');
 };

lib/resize.js

@@ -3,7 +3,7 @@
 const is = require('./is');
 
 /**
- * Weighting to apply to image crop.
+ * Weighting to apply when using contain/cover fit.
  * @member
  * @private
  */
@@ -21,7 +21,23 @@ const gravity = {
 };
 
 /**
- * Strategies for automagic crop behaviour.
+ * Position to apply when using contain/cover fit.
+ * @member
+ * @private
+ */
+const position = {
+  top: 1,
+  right: 2,
+  bottom: 3,
+  left: 4,
+  'right top': 5,
+  'right bottom': 6,
+  'left bottom': 7,
+  'left top': 8
+};
+
+/**
+ * Strategies for automagic cover behaviour.
  * @member
  * @private
  */
@@ -38,45 +54,161 @@ const strategy = {
 const kernel = {
   nearest: 'nearest',
   cubic: 'cubic',
+  mitchell: 'mitchell',
   lanczos2: 'lanczos2',
   lanczos3: 'lanczos3'
 };
 
 /**
- * Resize image to `width` x `height`.
- * By default, the resized image is centre cropped to the exact size specified.
+ * Methods by which an image can be resized to fit the provided dimensions.
+ * @member
+ * @private
+ */
+const fit = {
+  contain: 'contain',
+  cover: 'cover',
+  fill: 'fill',
+  inside: 'inside',
+  outside: 'outside'
+};
+
+/**
+ * Map external fit property to internal canvas property.
+ * @member
+ * @private
+ */
+const mapFitToCanvas = {
+  contain: 'embed',
+  cover: 'crop',
+  fill: 'ignore_aspect',
+  inside: 'max',
+  outside: 'min'
+};
+
+/**
+ * @private
+ */
+function isRotationExpected (options) {
+  return (options.angle % 360) !== 0 || options.useExifOrientation === true || options.rotationAngle !== 0;
+}
+
+/**
+ * Resize image to `width`, `height` or `width x height`.
  *
- * Possible kernels are:
+ * When both a `width` and `height` are provided, the possible methods by which the image should **fit** these are:
+ * - `cover`: (default) Preserving aspect ratio, ensure the image covers both provided dimensions by cropping/clipping to fit.
+ * - `contain`: Preserving aspect ratio, contain within both provided dimensions using "letterboxing" where necessary.
+ * - `fill`: Ignore the aspect ratio of the input and stretch to both provided dimensions.
+ * - `inside`: Preserving aspect ratio, resize the image to be as large as possible while ensuring its dimensions are less than or equal to both those specified.
+ * - `outside`: Preserving aspect ratio, resize the image to be as small as possible while ensuring its dimensions are greater than or equal to both those specified.
+ *
+ * Some of these values are based on the [object-fit](https://developer.mozilla.org/en-US/docs/Web/CSS/object-fit) CSS property.
+ *
+ * When using a `fit` of `cover` or `contain`, the default **position** is `centre`. Other options are:
+ * - `sharp.position`: `top`, `right top`, `right`, `right bottom`, `bottom`, `left bottom`, `left`, `left top`.
+ * - `sharp.gravity`: `north`, `northeast`, `east`, `southeast`, `south`, `southwest`, `west`, `northwest`, `center` or `centre`.
+ * - `sharp.strategy`: `cover` only, dynamically crop using either the `entropy` or `attention` strategy.
+ *
+ * Some of these values are based on the [object-position](https://developer.mozilla.org/en-US/docs/Web/CSS/object-position) CSS property.
+ *
+ * The experimental strategy-based approach resizes so one dimension is at its target length
+ * then repeatedly ranks edge regions, discarding the edge with the lowest score based on the selected strategy.
+ * - `entropy`: focus on the region with the highest [Shannon entropy](https://en.wikipedia.org/wiki/Entropy_%28information_theory%29).
+ * - `attention`: focus on the region with the highest luminance frequency, colour saturation and presence of skin tones.
+ *
+ * Possible interpolation kernels are:
  * - `nearest`: Use [nearest neighbour interpolation](http://en.wikipedia.org/wiki/Nearest-neighbor_interpolation).
  * - `cubic`: Use a [Catmull-Rom spline](https://en.wikipedia.org/wiki/Centripetal_Catmull%E2%80%93Rom_spline).
+ * - `mitchell`: Use a [Mitchell-Netravali spline](https://www.cs.utexas.edu/~fussell/courses/cs384g-fall2013/lectures/mitchell/Mitchell.pdf).
  * - `lanczos2`: Use a [Lanczos kernel](https://en.wikipedia.org/wiki/Lanczos_resampling#Lanczos_kernel) with `a=2`.
  * - `lanczos3`: Use a Lanczos kernel with `a=3` (the default).
  *
  * @example
- * sharp(inputBuffer)
- *   .resize(200, 300, {
- *     kernel: sharp.kernel.nearest
- *   })
- *   .background('white')
- *   .embed()
- *   .toFile('output.tiff')
- *   .then(function() {
- *     // output.tiff is a 200 pixels wide and 300 pixels high image
- *     // containing a nearest-neighbour scaled version, embedded on a white canvas,
- *     // of the image data in inputBuffer
+ * sharp(input)
+ *   .resize({ width: 100 })
+ *   .toBuffer()
+ *   .then(data => {
+ *     // 100 pixels wide, auto-scaled height
  *   });
  *
- * @param {Number} [width] - pixels wide the resultant image should be. Use `null` or `undefined` to auto-scale the width to match the height.
- * @param {Number} [height] - pixels high the resultant image should be. Use `null` or `undefined` to auto-scale the height to match the width.
+ * @example
+ * sharp(input)
+ *   .resize({ height: 100 })
+ *   .toBuffer()
+ *   .then(data => {
+ *     // 100 pixels high, auto-scaled width
+ *   });
+ *
+ * @example
+ * sharp(input)
+ *   .resize(200, 300, {
+ *     kernel: sharp.kernel.nearest,
+ *     fit: 'contain',
+ *     position: 'right top',
+ *     background: { r: 255, g: 255, b: 255, alpha: 0.5 }
+ *   })
+ *   .toFile('output.png')
+ *   .then(() => {
+ *     // output.png is a 200 pixels wide and 300 pixels high image
+ *     // containing a nearest-neighbour scaled version
+ *     // contained within the north-east corner of a semi-transparent white canvas
+ *   });
+ *
+ * @example
+ * const transformer = sharp()
+ *   .resize({
+ *     width: 200,
+ *     height: 200,
+ *     fit: sharp.fit.cover,
+ *     position: sharp.strategy.entropy
+ *   });
+ * // Read image data from readableStream
+ * // Write 200px square auto-cropped image data to writableStream
+ * readableStream
+ *   .pipe(transformer)
+ *   .pipe(writableStream);
+ *
+ * @example
+ * sharp(input)
+ *   .resize(200, 200, {
+ *     fit: sharp.fit.inside,
+ *     withoutEnlargement: true
+ *   })
+ *   .toFormat('jpeg')
+ *   .toBuffer()
+ *   .then(function(outputBuffer) {
+ *     // outputBuffer contains JPEG image data
+ *     // no wider and no higher than 200 pixels
+ *     // and no larger than the input image
+ *   });
+ *
+ * @example
+ * const scaleByHalf = await sharp(input)
+ *   .metadata()
+ *   .then(({ width }) => sharp(input)
+ *     .resize(Math.round(width * 0.5))
+ *     .toBuffer()
+ *   );
+ *
+ * @param {number} [width] - pixels wide the resultant image should be. Use `null` or `undefined` to auto-scale the width to match the height.
+ * @param {number} [height] - pixels high the resultant image should be. Use `null` or `undefined` to auto-scale the height to match the width.
  * @param {Object} [options]
+ * @param {String} [options.width] - alternative means of specifying `width`. If both are present this take priority.
+ * @param {String} [options.height] - alternative means of specifying `height`. If both are present this take priority.
+ * @param {String} [options.fit='cover'] - how the image should be resized to fit both provided dimensions, one of `cover`, `contain`, `fill`, `inside` or `outside`.
+ * @param {String} [options.position='centre'] - position, gravity or strategy to use when `fit` is `cover` or `contain`.
+ * @param {String|Object} [options.background={r: 0, g: 0, b: 0, alpha: 1}] - background colour when using a `fit` of `contain`, parsed by the [color](https://www.npmjs.org/package/color) module, defaults to black without transparency.
  * @param {String} [options.kernel='lanczos3'] - the kernel to use for image reduction.
+ * @param {Boolean} [options.withoutEnlargement=false] - do not enlarge if the width *or* height are already less than the specified dimensions, equivalent to GraphicsMagick's `>` geometry option.
  * @param {Boolean} [options.fastShrinkOnLoad=true] - take greater advantage of the JPEG and WebP shrink-on-load feature, which can lead to a slight moiré pattern on some images.
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
  */
 function resize (width, height, options) {
   if (is.defined(width)) {
-    if (is.integer(width) && width > 0) {
+    if (is.object(width) && !is.defined(options)) {
+      options = width;
+    } else if (is.integer(width) && width > 0) {
       this.options.width = width;
     } else {
       throw is.invalidParameterError('width', 'positive integer', width);
@@ -94,6 +226,44 @@ function resize (width, height, options) {
     this.options.height = -1;
   }
   if (is.object(options)) {
+    // Width
+    if (is.defined(options.width)) {
+      if (is.integer(options.width) && options.width > 0) {
+        this.options.width = options.width;
+      } else {
+        throw is.invalidParameterError('width', 'positive integer', options.width);
+      }
+    }
+    // Height
+    if (is.defined(options.height)) {
+      if (is.integer(options.height) && options.height > 0) {
+        this.options.height = options.height;
+      } else {
+        throw is.invalidParameterError('height', 'positive integer', options.height);
+      }
+    }
+    // Fit
+    if (is.defined(options.fit)) {
+      const canvas = mapFitToCanvas[options.fit];
+      if (is.string(canvas)) {
+        this.options.canvas = canvas;
+      } else {
+        throw is.invalidParameterError('fit', 'valid fit', options.fit);
+      }
+    }
+    // Position
+    if (is.defined(options.position)) {
+      const pos = is.integer(options.position)
+        ? options.position
+        : strategy[options.position] || position[options.position] || gravity[options.position];
+      if (is.integer(pos) && (is.inRange(pos, 0, 8) || is.inRange(pos, 16, 17))) {
+        this.options.position = pos;
+      } else {
+        throw is.invalidParameterError('position', 'valid position/gravity/strategy', options.position);
+      }
+    }
+    // Background
+    this._setBackgroundColourOption('resizeBackground', options.background);
     // Kernel
     if (is.defined(options.kernel)) {
       if (is.string(kernel[options.kernel])) {
@@ -102,6 +272,10 @@ function resize (width, height, options) {
         throw is.invalidParameterError('kernel', 'valid kernel name', options.kernel);
       }
     }
+    // Without enlargement
+    if (is.defined(options.withoutEnlargement)) {
+      this._setBooleanOption('withoutEnlargement', options.withoutEnlargement);
+    }
     // Shrink on load
     if (is.defined(options.fastShrinkOnLoad)) {
       this._setBooleanOption('fastShrinkOnLoad', options.fastShrinkOnLoad);
@@ -111,157 +285,152 @@ function resize (width, height, options) {
 }
 
 /**
- * Crop the resized image to the exact size specified, the default behaviour.
- *
- * Possible attributes of the optional `sharp.gravity` are `north`, `northeast`, `east`, `southeast`, `south`,
- * `southwest`, `west`, `northwest`, `center` and `centre`.
- *
- * The experimental strategy-based approach resizes so one dimension is at its target length
- * then repeatedly ranks edge regions, discarding the edge with the lowest score based on the selected strategy.
- * - `entropy`: focus on the region with the highest [Shannon entropy](https://en.wikipedia.org/wiki/Entropy_%28information_theory%29).
- * - `attention`: focus on the region with the highest luminance frequency, colour saturation and presence of skin tones.
+ * Extends/pads the edges of the image with the provided background colour.
+ * This operation will always occur after resizing and extraction, if any.
  *
  * @example
- * const transformer = sharp()
- *   .resize(200, 200)
- *   .crop(sharp.strategy.entropy)
- *   .on('error', function(err) {
- *     console.log(err);
- *   });
- * // Read image data from readableStream
- * // Write 200px square auto-cropped image data to writableStream
- * readableStream.pipe(transformer).pipe(writableStream);
+ * // Resize to 140 pixels wide, then add 10 transparent pixels
+ * // to the top, left and right edges and 20 to the bottom edge
+ * sharp(input)
+ *   .resize(140)
+ *   .extend({
+ *     top: 10,
+ *     bottom: 20,
+ *     left: 10,
+ *     right: 10,
+ *     background: { r: 0, g: 0, b: 0, alpha: 0 }
+ *   })
+ *   ...
  *
- * @param {String} [crop='centre'] - A member of `sharp.gravity` to crop to an edge/corner or `sharp.strategy` to crop dynamically.
+* @example
+ * // Add a row of 10 red pixels to the bottom
+ * sharp(input)
+ *   .extend({
+ *     bottom: 10,
+ *     background: 'red'
+ *   })
+ *   ...
+ *
+ * @param {(number|Object)} extend - single pixel count to add to all edges or an Object with per-edge counts
+ * @param {number} [extend.top=0]
+ * @param {number} [extend.left=0]
+ * @param {number} [extend.bottom=0]
+ * @param {number} [extend.right=0]
+ * @param {String|Object} [extend.background={r: 0, g: 0, b: 0, alpha: 1}] - background colour, parsed by the [color](https://www.npmjs.org/package/color) module, defaults to black without transparency.
  * @returns {Sharp}
  * @throws {Error} Invalid parameters
- */
-function crop (crop) {
-  this.options.canvas = 'crop';
-  if (!is.defined(crop)) {
-    // Default
-    this.options.crop = gravity.center;
-  } else if (is.integer(crop) && is.inRange(crop, 0, 8)) {
-    // Gravity (numeric)
-    this.options.crop = crop;
-  } else if (is.string(crop) && is.integer(gravity[crop])) {
-    // Gravity (string)
-    this.options.crop = gravity[crop];
-  } else if (is.integer(crop) && crop >= strategy.entropy) {
-    // Strategy
-    this.options.crop = crop;
-  } else if (is.string(crop) && is.integer(strategy[crop])) {
-    // Strategy (string)
-    this.options.crop = strategy[crop];
-  } else {
-    throw is.invalidParameterError('crop', 'valid crop id/name/strategy', crop);
-  }
-  return this;
-}
-
-/**
- * Preserving aspect ratio, resize the image to the maximum `width` or `height` specified
- * then embed on a background of the exact `width` and `height` specified.
- *
- * If the background contains an alpha value then WebP and PNG format output images will
- * contain an alpha channel, even when the input image does not.
- *
- * @example
- * sharp('input.gif')
- *   .resize(200, 300)
- *   .background({r: 0, g: 0, b: 0, alpha: 0})
- *   .embed()
- *   .toFormat(sharp.format.webp)
- *   .toBuffer(function(err, outputBuffer) {
- *     if (err) {
- *       throw err;
- *     }
- *     // outputBuffer contains WebP image data of a 200 pixels wide and 300 pixels high
- *     // containing a scaled version, embedded on a transparent canvas, of input.gif
- *   });
- * @param {String} [embed='centre'] - A member of `sharp.gravity` to embed to an edge/corner.
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
-function embed (embed) {
-  this.options.canvas = 'embed';
-
-  if (!is.defined(embed)) {
-    // Default
-    this.options.embed = gravity.center;
-  } else if (is.integer(embed) && is.inRange(embed, 0, 8)) {
-    // Gravity (numeric)
-    this.options.embed = embed;
-  } else if (is.string(embed) && is.integer(gravity[embed])) {
-    // Gravity (string)
-    this.options.embed = gravity[embed];
-  } else {
-    throw is.invalidParameterError('embed', 'valid embed id/name', embed);
-  }
-
-  return this;
-}
-
-/**
- * Preserving aspect ratio, resize the image to be as large as possible
- * while ensuring its dimensions are less than or equal to the `width` and `height` specified.
- *
- * Both `width` and `height` must be provided via `resize` otherwise the behaviour will default to `crop`.
- *
- * @example
- * sharp(inputBuffer)
- *   .resize(200, 200)
- *   .max()
- *   .toFormat('jpeg')
- *   .toBuffer()
- *   .then(function(outputBuffer) {
- *     // outputBuffer contains JPEG image data no wider than 200 pixels and no higher
- *     // than 200 pixels regardless of the inputBuffer image dimensions
- *   });
- *
- * @returns {Sharp}
- */
-function max () {
-  this.options.canvas = 'max';
-  return this;
-}
-
-/**
- * Preserving aspect ratio, resize the image to be as small as possible
- * while ensuring its dimensions are greater than or equal to the `width` and `height` specified.
- *
- * Both `width` and `height` must be provided via `resize` otherwise the behaviour will default to `crop`.
- *
- * @returns {Sharp}
- */
-function min () {
-  this.options.canvas = 'min';
-  return this;
-}
-
-/**
- * Ignoring the aspect ratio of the input, stretch the image to
- * the exact `width` and/or `height` provided via `resize`.
- * @returns {Sharp}
- */
-function ignoreAspectRatio () {
-  this.options.canvas = 'ignore_aspect';
-  return this;
-}
-
-/**
- * Do not enlarge the output image if the input image width *or* height are already less than the required dimensions.
- * This is equivalent to GraphicsMagick's `>` geometry option:
- * "*change the dimensions of the image only if its width or height exceeds the geometry specification*".
- * Use with `max()` to preserve the image's aspect ratio.
- *
- * The default behaviour *before* function call is `false`, meaning the image will be enlarged.
- *
- * @param {Boolean} [withoutEnlargement=true]
- * @returns {Sharp}
 */
-function withoutEnlargement (withoutEnlargement) {
-  this.options.withoutEnlargement = is.bool(withoutEnlargement) ? withoutEnlargement : true;
+function extend (extend) {
+  if (is.integer(extend) && extend > 0) {
+    this.options.extendTop = extend;
+    this.options.extendBottom = extend;
+    this.options.extendLeft = extend;
+    this.options.extendRight = extend;
+  } else if (is.object(extend)) {
+    if (is.defined(extend.top)) {
+      if (is.integer(extend.top) && extend.top >= 0) {
+        this.options.extendTop = extend.top;
+      } else {
+        throw is.invalidParameterError('top', 'positive integer', extend.top);
+      }
+    }
+    if (is.defined(extend.bottom)) {
+      if (is.integer(extend.bottom) && extend.bottom >= 0) {
+        this.options.extendBottom = extend.bottom;
+      } else {
+        throw is.invalidParameterError('bottom', 'positive integer', extend.bottom);
+      }
+    }
+    if (is.defined(extend.left)) {
+      if (is.integer(extend.left) && extend.left >= 0) {
+        this.options.extendLeft = extend.left;
+      } else {
+        throw is.invalidParameterError('left', 'positive integer', extend.left);
+      }
+    }
+    if (is.defined(extend.right)) {
+      if (is.integer(extend.right) && extend.right >= 0) {
+        this.options.extendRight = extend.right;
+      } else {
+        throw is.invalidParameterError('right', 'positive integer', extend.right);
+      }
+    }
+    this._setBackgroundColourOption('extendBackground', extend.background);
+  } else {
+    throw is.invalidParameterError('extend', 'integer or object', extend);
+  }
+  return this;
+}
+
+/**
+ * Extract/crop a region of the image.
+ *
+ * - Use `extract` before `resize` for pre-resize extraction.
+ * - Use `extract` after `resize` for post-resize extraction.
+ * - Use `extract` before and after for both.
+ *
+ * @example
+ * sharp(input)
+ *   .extract({ left: left, top: top, width: width, height: height })
+ *   .toFile(output, function(err) {
+ *     // Extract a region of the input image, saving in the same format.
+ *   });
+ * @example
+ * sharp(input)
+ *   .extract({ left: leftOffsetPre, top: topOffsetPre, width: widthPre, height: heightPre })
+ *   .resize(width, height)
+ *   .extract({ left: leftOffsetPost, top: topOffsetPost, width: widthPost, height: heightPost })
+ *   .toFile(output, function(err) {
+ *     // Extract a region, resize, then extract from the resized image
+ *   });
+ *
+ * @param {Object} options - describes the region to extract using integral pixel values
+ * @param {number} options.left - zero-indexed offset from left edge
+ * @param {number} options.top - zero-indexed offset from top edge
+ * @param {number} options.width - width of region to extract
+ * @param {number} options.height - height of region to extract
+ * @returns {Sharp}
+ * @throws {Error} Invalid parameters
+ */
+function extract (options) {
+  const suffix = this.options.width === -1 && this.options.height === -1 ? 'Pre' : 'Post';
+  ['left', 'top', 'width', 'height'].forEach(function (name) {
+    const value = options[name];
+    if (is.integer(value) && value >= 0) {
+      this.options[name + (name === 'left' || name === 'top' ? 'Offset' : '') + suffix] = value;
+    } else {
+      throw is.invalidParameterError(name, 'integer', value);
+    }
+  }, this);
+  // Ensure existing rotation occurs before pre-resize extraction
+  if (suffix === 'Pre' && isRotationExpected(this.options)) {
+    this.options.rotateBeforePreExtract = true;
+  }
+  return this;
+}
+
+/**
+ * Trim "boring" pixels from all edges that contain values similar to the top-left pixel.
+ * Images consisting entirely of a single colour will calculate "boring" using the alpha channel, if any.
+ *
+ * The `info` response Object, obtained from callback of `.toFile()` or `.toBuffer()`,
+ * will contain `trimOffsetLeft` and `trimOffsetTop` properties.
+ *
+ * @param {number} [threshold=10] the allowed difference from the top-left pixel, a number greater than zero.
+ * @returns {Sharp}
+ * @throws {Error} Invalid parameters
+ */
+function trim (threshold) {
+  if (!is.defined(threshold)) {
+    this.options.trimThreshold = 10;
+  } else if (is.number(threshold) && threshold > 0) {
+    this.options.trimThreshold = threshold;
+  } else {
+    throw is.invalidParameterError('threshold', 'number greater than zero', threshold);
+  }
+  if (this.options.trimThreshold && isRotationExpected(this.options)) {
+    this.options.rotateBeforePreExtract = true;
+  }
   return this;
 }
 
@@ -270,19 +439,16 @@ function withoutEnlargement (withoutEnlargement) {
  * @private
  */
 module.exports = function (Sharp) {
-  [
+  Object.assign(Sharp.prototype, {
     resize,
-    crop,
-    embed,
-    max,
-    min,
-    ignoreAspectRatio,
-    withoutEnlargement
-  ].forEach(function (f) {
-    Sharp.prototype[f.name] = f;
+    extend,
+    extract,
+    trim
   });
   // Class attributes
   Sharp.gravity = gravity;
   Sharp.strategy = strategy;
   Sharp.kernel = kernel;
+  Sharp.fit = fit;
+  Sharp.position = position;
 };

lib/sharp.js

@@ -0,0 +1,31 @@
+'use strict';
+
+const platformAndArch = require('./platform')();
+
+/* istanbul ignore next */
+try {
+  module.exports = require(`../build/Release/sharp-${platformAndArch}.node`);
+} catch (err) {
+  // Bail early if bindings aren't available
+  const help = ['', 'Something went wrong installing the "sharp" module', '', err.message, '', 'Possible solutions:'];
+  if (/dylib/.test(err.message) && /Incompatible library version/.test(err.message)) {
+    help.push('- Update Homebrew: "brew update && brew upgrade vips"');
+  } else {
+    help.push(
+      '- Install with the --verbose flag and look for errors: "npm install --ignore-scripts=false --verbose sharp"',
+      `- Install for the current runtime: "npm install --platform=${process.platform} --arch=${process.arch} sharp"`
+    );
+  }
+  help.push(
+    '- Consult the installation documentation: https://sharp.pixelplumbing.com/install'
+  );
+  // Check loaded
+  if (process.platform === 'win32') {
+    const loadedModule = Object.keys(require.cache).find((i) => /[\\/]build[\\/]Release[\\/]sharp(.*)\.node$/.test(i));
+    if (loadedModule) {
+      const [, loadedPackage] = loadedModule.match(/node_modules[\\/]([^\\/]+)[\\/]/);
+      help.push(`- Ensure the version of sharp aligns with the ${loadedPackage} package: "npm ls sharp"`);
+    }
+  }
+  throw new Error(help.join('\n'));
+}

lib/utility.js

@@ -1,7 +1,53 @@
 'use strict';
 
+const events = require('events');
+const detectLibc = require('detect-libc');
+
 const is = require('./is');
-const sharp = require('../build/Release/sharp.node');
+const platformAndArch = require('./platform')();
+const sharp = require('./sharp');
+
+/**
+ * An Object containing nested boolean values representing the available input and output formats/methods.
+ * @member
+ * @example
+ * console.log(sharp.format);
+ * @returns {Object}
+ */
+const format = sharp.format();
+
+/**
+ * An Object containing the available interpolators and their proper values
+ * @readonly
+ * @enum {string}
+ */
+const interpolators = {
+  /** [Nearest neighbour interpolation](http://en.wikipedia.org/wiki/Nearest-neighbor_interpolation). Suitable for image enlargement only. */
+  nearest: 'nearest',
+  /** [Bilinear interpolation](http://en.wikipedia.org/wiki/Bilinear_interpolation). Faster than bicubic but with less smooth results. */
+  bilinear: 'bilinear',
+  /** [Bicubic interpolation](http://en.wikipedia.org/wiki/Bicubic_interpolation) (the default). */
+  bicubic: 'bicubic',
+  /** [LBB interpolation](https://github.com/jcupitt/libvips/blob/master/libvips/resample/lbb.cpp#L100). Prevents some "[acutance](http://en.wikipedia.org/wiki/Acutance)" but typically reduces performance by a factor of 2. */
+  locallyBoundedBicubic: 'lbb',
+  /** [Nohalo interpolation](http://eprints.soton.ac.uk/268086/). Prevents acutance but typically reduces performance by a factor of 3. */
+  nohalo: 'nohalo',
+  /** [VSQBS interpolation](https://github.com/jcupitt/libvips/blob/master/libvips/resample/vsqbs.cpp#L48). Prevents "staircasing" when enlarging. */
+  vertexSplitQuadraticBasisSpline: 'vsqbs'
+};
+
+/**
+ * An Object containing the version numbers of libvips and its dependencies.
+ * @member
+ * @example
+ * console.log(sharp.versions);
+ */
+let versions = {
+  vips: sharp.libvipsVersion()
+};
+try {
+  versions = require(`../vendor/${versions.vips}/${platformAndArch}/versions.json`);
+} catch (err) {}
 
 /**
  * Gets or, when options are provided, sets the limits of _libvips'_ operation cache.
@@ -16,10 +62,10 @@ const sharp = require('../build/Release/sharp.node');
  * sharp.cache( { files: 0 } );
  * sharp.cache(false);
  *
- * @param {Object|Boolean} [options=true] - Object with the following attributes, or Boolean where true uses default cache settings and false removes all caching
- * @param {Number} [options.memory=50] - is the maximum memory in MB to use for this cache
- * @param {Number} [options.files=20] - is the maximum number of files to hold open
- * @param {Number} [options.items=100] - is the maximum number of operations to cache
+ * @param {Object|boolean} [options=true] - Object with the following attributes, or boolean where true uses default cache settings and false removes all caching
+ * @param {number} [options.memory=50] - is the maximum memory in MB to use for this cache
+ * @param {number} [options.files=20] - is the maximum number of files to hold open
+ * @param {number} [options.items=100] - is the maximum number of operations to cache
  * @returns {Object}
  */
 function cache (options) {
@@ -41,8 +87,12 @@ cache(true);
 /**
  * Gets or, when a concurrency is provided, sets
  * the number of threads _libvips'_ should create to process each image.
- * The default value is the number of CPU cores.
- * A value of `0` will reset to this default.
+ *
+ * The default value is the number of CPU cores,
+ * except when using glibc-based Linux without jemalloc,
+ * where the default is `1` to help reduce memory fragmentation.
+ *
+ * A value of `0` will reset this to the number of CPU cores.
  *
  * The maximum number of images that can be processed in parallel
  * is limited by libuv's `UV_THREADPOOL_SIZE` environment variable.
@@ -54,12 +104,29 @@ cache(true);
  * sharp.concurrency(2); // 2
  * sharp.concurrency(0); // 4
  *
- * @param {Number} [concurrency]
- * @returns {Number} concurrency
+ * @param {number} [concurrency]
+ * @returns {number} concurrency
  */
 function concurrency (concurrency) {
   return sharp.concurrency(is.integer(concurrency) ? concurrency : null);
 }
+/* istanbul ignore next */
+if (detectLibc.family === detectLibc.GLIBC && !sharp._isUsingJemalloc()) {
+  // Reduce default concurrency to 1 when using glibc memory allocator
+  sharp.concurrency(1);
+}
+
+/**
+ * An EventEmitter that emits a `change` event when a task is either:
+ * - queued, waiting for _libuv_ to provide a worker thread
+ * - complete
+ * @member
+ * @example
+ * sharp.queue.on('change', function(queueLength) {
+ *   console.log('Queue contains ' + queueLength + ' task(s)');
+ * });
+ */
+const queue = new events.EventEmitter();
 
 /**
  * Provides access to internal task counters.
@@ -82,35 +149,32 @@ function counters () {
  * Improves the performance of `resize`, `blur` and `sharpen` operations
  * by taking advantage of the SIMD vector unit of the CPU, e.g. Intel SSE and ARM NEON.
  *
- * This feature is currently off by default but future versions may reverse this.
- * Versions of liborc prior to 0.4.25 are known to segfault under heavy load.
- *
  * @example
  * const simd = sharp.simd();
- * // simd is `true` if SIMD is currently enabled
+ * // simd is `true` if the runtime use of liborc is currently enabled
  * @example
- * const simd = sharp.simd(true);
- * // attempts to enable the use of SIMD, returning true if available
+ * const simd = sharp.simd(false);
+ * // prevent libvips from using liborc at runtime
  *
- * @param {Boolean} [simd=false]
- * @returns {Boolean}
+ * @param {boolean} [simd=true]
+ * @returns {boolean}
  */
 function simd (simd) {
   return sharp.simd(is.bool(simd) ? simd : null);
 }
-simd(false);
+simd(true);
 
 /**
  * Decorate the Sharp class with utility-related functions.
  * @private
  */
 module.exports = function (Sharp) {
-  [
-    cache,
-    concurrency,
-    counters,
-    simd
-  ].forEach(function (f) {
-    Sharp[f.name] = f;
-  });
+  Sharp.cache = cache;
+  Sharp.concurrency = concurrency;
+  Sharp.counters = counters;
+  Sharp.simd = simd;
+  Sharp.format = format;
+  Sharp.interpolators = interpolators;
+  Sharp.versions = versions;
+  Sharp.queue = queue;
 };

mkdocs.yml

@@ -1,25 +0,0 @@
-site_name: sharp
-site_url: http://sharp.pixelplumbing.com/
-repo_url: https://github.com/lovell/sharp
-site_description: High performance Node.js image processing, the fastest module to resize JPEG, PNG, WebP and TIFF images
-copyright: <a href="https://pixelplumbing.com/">pixelplumbing.com</a>
-google_analytics: ['UA-13034748-12', 'sharp.pixelplumbing.com']
-theme: readthedocs
-markdown_extensions:
-  - toc:
-      permalink: True
-pages:
-  - Home: index.md
-  - Installation: install.md
-  - API:
-    - Constructor: api-constructor.md
-    - Input: api-input.md
-    - Output: api-output.md
-    - "Resizing images": api-resize.md
-    - "Compositing images": api-composite.md
-    - "Image operations": api-operation.md
-    - "Colour manipulation": api-colour.md
-    - "Channel manipulation": api-channel.md
-    - Utilities: api-utility.md
-  - Performance: performance.md
-  - Changelog: changelog.md

package.json

@@ -1,7 +1,7 @@
 {
   "name": "sharp",
-  "description": "High performance Node.js image processing, the fastest module to resize JPEG, PNG, WebP and TIFF images",
-  "version": "0.19.1",
+  "description": "High performance Node.js image processing, the fastest module to resize JPEG, PNG, WebP, AVIF and TIFF images",
+  "version": "0.29.3",
   "author": "Lovell Fuller <npm@lovell.info>",
   "homepage": "https://github.com/lovell/sharp",
   "contributors": [
@@ -45,16 +45,62 @@
     "Kenric D'Souza <kenric.dsouza@gmail.com>",
     "Oleh Aleinyk <oleg.aleynik@gmail.com>",
     "Marcel Bretschneider <marcel.bretschneider@gmail.com>",
-    "Andrea Bianco <andrea.bianco@unibas.ch>"
+    "Andrea Bianco <andrea.bianco@unibas.ch>",
+    "Rik Heywood <rik@rik.org>",
+    "Thomas Parisot <hi@oncletom.io>",
+    "Nathan Graves <nathanrgraves+github@gmail.com>",
+    "Tom Lokhorst <tom@lokhorst.eu>",
+    "Espen Hovlandsdal <espen@hovlandsdal.com>",
+    "Sylvain Dumont <sylvain.dumont35@gmail.com>",
+    "Alun Davies <alun.owain.davies@googlemail.com>",
+    "Aidan Hoolachan <ajhoolachan21@gmail.com>",
+    "Axel Eirola <axel.eirola@iki.fi>",
+    "Freezy <freezy@xbmc.org>",
+    "Daiz <taneli.vatanen@gmail.com>",
+    "Julian Aubourg <j@ubourg.net>",
+    "Keith Belovay <keith@picthrive.com>",
+    "Michael B. Klein <mbklein@gmail.com>",
+    "Jordan Prudhomme <jordan@raboland.fr>",
+    "Ilya Ovdin <iovdin@gmail.com>",
+    "Andargor <andargor@yahoo.com>",
+    "Paul Neave <paul.neave@gmail.com>",
+    "Brendan Kennedy <brenwken@gmail.com>",
+    "Brychan Bennett-Odlum <git@brychan.io>",
+    "Edward Silverton <e.silverton@gmail.com>",
+    "Roman Malieiev <aromaleev@gmail.com>",
+    "Tomas Szabo <tomas.szabo@deftomat.com>",
+    "Robert O'Rourke <robert@o-rourke.org>",
+    "Guillermo Alfonso Varela Chouciño <guillevch@gmail.com>",
+    "Christian Flintrup <chr@gigahost.dk>",
+    "Manan Jadhav <manan@motionden.com>",
+    "Leon Radley <leon@radley.se>",
+    "alza54 <alza54@thiocod.in>",
+    "Jacob Smith <jacob@frende.me>",
+    "Michael Nutt <michael@nutt.im>",
+    "Brad Parham <baparham@gmail.com>",
+    "Taneli Vatanen <taneli.vatanen@gmail.com>",
+    "Joris Dugué <zaruike10@gmail.com>"
   ],
   "scripts": {
-    "clean": "rm -rf node_modules/ build/ vendor/ coverage/ test/fixtures/output.*",
-    "test": "semistandard && cc && nyc --reporter=lcov --branches=99 mocha --slow=5000 --timeout=60000 ./test/unit/*.js",
-    "coverage": "./test/coverage/report.sh",
+    "install": "(node install/libvips && node install/dll-copy && prebuild-install) || (node install/can-compile && node-gyp rebuild && node install/dll-copy)",
+    "clean": "rm -rf node_modules/ build/ vendor/ .nyc_output/ coverage/ test/fixtures/output.*",
+    "test": "npm run test-lint && npm run test-unit && npm run test-licensing",
+    "test-lint": "semistandard && cpplint",
+    "test-unit": "nyc --reporter=lcov --branches=99 mocha --slow=1000 --timeout=60000 ./test/unit/*.js",
+    "test-licensing": "license-checker --production --summary --onlyAllow=\"Apache-2.0;BSD;ISC;MIT\"",
+    "test-coverage": "./test/coverage/report.sh",
     "test-leak": "./test/leak/leak.sh",
-    "docs": "for m in constructor input resize composite operation colour channel output utility; do documentation build --shallow --format=md lib/$m.js >docs/api-$m.md; done"
+    "docs-build": "documentation lint lib && node docs/build && node docs/search-index/build",
+    "docs-serve": "cd docs && npx serve",
+    "docs-publish": "cd docs && npx firebase-tools deploy --project pixelplumbing --only hosting:pixelplumbing-sharp"
   },
   "main": "lib/index.js",
+  "files": [
+    "binding.gyp",
+    "install/**",
+    "lib/**",
+    "src/**"
+  ],
   "repository": {
     "type": "git",
     "url": "git://github.com/lovell/sharp"
@@ -63,9 +109,11 @@
     "jpeg",
     "png",
     "webp",
+    "avif",
     "tiff",
     "gif",
     "svg",
+    "jp2",
     "dzi",
     "image",
     "resize",
@@ -76,32 +124,46 @@
     "vips"
   ],
   "dependencies": {
-    "color": "^3.0.0",
+    "color": "^4.0.1",
     "detect-libc": "^1.0.3",
-    "nan": "^2.9.2",
-    "semver": "^5.5.0",
-    "simple-get": "^2.7.0",
-    "tar": "^4.4.0",
+    "node-addon-api": "^4.2.0",
+    "prebuild-install": "^7.0.0",
+    "semver": "^7.3.5",
+    "simple-get": "^4.0.0",
+    "tar-fs": "^2.1.1",
     "tunnel-agent": "^0.6.0"
   },
   "devDependencies": {
-    "async": "^2.6.0",
-    "cc": "^1.0.1",
-    "documentation": "^5.4.0",
-    "exif-reader": "^1.0.2",
-    "icc": "^1.0.0",
-    "mocha": "^5.0.1",
-    "nyc": "^11.5.0",
-    "rimraf": "^2.6.2",
-    "semistandard": "^12.0.1",
-    "unzip": "^0.1.11"
+    "async": "^3.2.2",
+    "cc": "^3.0.1",
+    "decompress-zip": "^0.3.3",
+    "documentation": "^13.2.5",
+    "exif-reader": "^1.0.3",
+    "icc": "^2.0.0",
+    "license-checker": "^25.0.1",
+    "mocha": "^9.1.3",
+    "mock-fs": "^5.1.2",
+    "nyc": "^15.1.0",
+    "prebuild": "^11.0.0",
+    "rimraf": "^3.0.2",
+    "semistandard": "^16.0.1"
   },
   "license": "Apache-2.0",
   "config": {
-    "libvips": "8.6.1"
+    "libvips": "8.11.3",
+    "runtime": "napi",
+    "target": 5
   },
   "engines": {
-    "node": ">=4.5.0"
+    "node": ">=12.13.0"
+  },
+  "funding": {
+    "url": "https://opencollective.com/libvips"
+  },
+  "binary": {
+    "napi_versions": [
+      5
+    ]
   },
   "semistandard": {
     "env": [
@@ -111,10 +173,7 @@
   "cc": {
     "linelength": "120",
     "filter": [
-      "build/c++11",
-      "build/include",
-      "runtime/indentation_namespace",
-      "runtime/references"
+      "build/include"
     ]
   }
 }

src/common.cc

@@ -1,4 +1,4 @@
-// Copyright 2013, 2014, 2015, 2016, 2017 Lovell Fuller and contributors.
+// Copyright 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Lovell Fuller and contributors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -17,11 +17,10 @@
 #include <string.h>
 #include <vector>
 #include <queue>
-#include <mutex>
+#include <map>
+#include <mutex>  // NOLINT(build/c++11)
 
-#include <node.h>
-#include <node_buffer.h>
-#include <nan.h>
+#include <napi.h>
 #include <vips/vips8>
 
 #include "common.h"
@@ -30,49 +29,109 @@ using vips::VImage;
 
 namespace sharp {
 
-  // Convenience methods to access the attributes of a v8::Object
-  bool HasAttr(v8::Handle<v8::Object> obj, std::string attr) {
-    return Nan::Has(obj, Nan::New(attr).ToLocalChecked()).FromJust();
+  // Convenience methods to access the attributes of a Napi::Object
+  bool HasAttr(Napi::Object obj, std::string attr) {
+    return obj.Has(attr);
   }
-  std::string AttrAsStr(v8::Handle<v8::Object> obj, std::string attr) {
-    return *Nan::Utf8String(Nan::Get(obj, Nan::New(attr).ToLocalChecked()).ToLocalChecked());
+  std::string AttrAsStr(Napi::Object obj, std::string attr) {
+    return obj.Get(attr).As<Napi::String>();
+  }
+  std::string AttrAsStr(Napi::Object obj, unsigned int const attr) {
+    return obj.Get(attr).As<Napi::String>();
+  }
+  uint32_t AttrAsUint32(Napi::Object obj, std::string attr) {
+    return obj.Get(attr).As<Napi::Number>().Uint32Value();
+  }
+  int32_t AttrAsInt32(Napi::Object obj, std::string attr) {
+    return obj.Get(attr).As<Napi::Number>().Int32Value();
+  }
+  int32_t AttrAsInt32(Napi::Object obj, unsigned int const attr) {
+    return obj.Get(attr).As<Napi::Number>().Int32Value();
+  }
+  double AttrAsDouble(Napi::Object obj, std::string attr) {
+    return obj.Get(attr).As<Napi::Number>().DoubleValue();
+  }
+  double AttrAsDouble(Napi::Object obj, unsigned int const attr) {
+    return obj.Get(attr).As<Napi::Number>().DoubleValue();
+  }
+  bool AttrAsBool(Napi::Object obj, std::string attr) {
+    return obj.Get(attr).As<Napi::Boolean>().Value();
+  }
+  std::vector<double> AttrAsVectorOfDouble(Napi::Object obj, std::string attr) {
+    Napi::Array napiArray = obj.Get(attr).As<Napi::Array>();
+    std::vector<double> vectorOfDouble(napiArray.Length());
+    for (unsigned int i = 0; i < napiArray.Length(); i++) {
+      vectorOfDouble[i] = AttrAsDouble(napiArray, i);
+    }
+    return vectorOfDouble;
+  }
+  std::vector<int32_t> AttrAsInt32Vector(Napi::Object obj, std::string attr) {
+    Napi::Array array = obj.Get(attr).As<Napi::Array>();
+    std::vector<int32_t> vector(array.Length());
+    for (unsigned int i = 0; i < array.Length(); i++) {
+      vector[i] = AttrAsInt32(array, i);
+    }
+    return vector;
   }
 
-  // Create an InputDescriptor instance from a v8::Object describing an input image
-  InputDescriptor* CreateInputDescriptor(
-    v8::Handle<v8::Object> input, std::vector<v8::Local<v8::Object>> &buffersToPersist
-  ) {
-    Nan::HandleScope();
+  // Create an InputDescriptor instance from a Napi::Object describing an input image
+  InputDescriptor* CreateInputDescriptor(Napi::Object input) {
     InputDescriptor *descriptor = new InputDescriptor;
     if (HasAttr(input, "file")) {
       descriptor->file = AttrAsStr(input, "file");
     } else if (HasAttr(input, "buffer")) {
-      v8::Local<v8::Object> buffer = AttrAs<v8::Object>(input, "buffer");
-      descriptor->bufferLength = node::Buffer::Length(buffer);
-      descriptor->buffer = node::Buffer::Data(buffer);
-      buffersToPersist.push_back(buffer);
+      Napi::Buffer<char> buffer = input.Get("buffer").As<Napi::Buffer<char>>();
+      descriptor->bufferLength = buffer.Length();
+      descriptor->buffer = buffer.Data();
+      descriptor->isBuffer = TRUE;
     }
-    descriptor->failOnError = AttrTo<bool>(input, "failOnError");
+    descriptor->failOnError = AttrAsBool(input, "failOnError");
     // Density for vector-based input
     if (HasAttr(input, "density")) {
-      descriptor->density = AttrTo<uint32_t>(input, "density");
+      descriptor->density = AttrAsDouble(input, "density");
     }
     // Raw pixel input
     if (HasAttr(input, "rawChannels")) {
-      descriptor->rawChannels = AttrTo<uint32_t>(input, "rawChannels");
-      descriptor->rawWidth = AttrTo<uint32_t>(input, "rawWidth");
-      descriptor->rawHeight = AttrTo<uint32_t>(input, "rawHeight");
+      descriptor->rawDepth = static_cast<VipsBandFormat>(
+        vips_enum_from_nick(nullptr, VIPS_TYPE_BAND_FORMAT,
+        AttrAsStr(input, "rawDepth").data()));
+      descriptor->rawChannels = AttrAsUint32(input, "rawChannels");
+      descriptor->rawWidth = AttrAsUint32(input, "rawWidth");
+      descriptor->rawHeight = AttrAsUint32(input, "rawHeight");
+      descriptor->rawPremultiplied = AttrAsBool(input, "rawPremultiplied");
+    }
+    // Multi-page input (GIF, TIFF, PDF)
+    if (HasAttr(input, "pages")) {
+      descriptor->pages = AttrAsInt32(input, "pages");
+    }
+    if (HasAttr(input, "page")) {
+      descriptor->page = AttrAsUint32(input, "page");
+    }
+    // Multi-level input (OpenSlide)
+    if (HasAttr(input, "level")) {
+      descriptor->level = AttrAsUint32(input, "level");
+    }
+    // subIFD (OME-TIFF)
+    if (HasAttr(input, "subifd")) {
+      descriptor->subifd = AttrAsInt32(input, "subifd");
     }
     // Create new image
     if (HasAttr(input, "createChannels")) {
-      descriptor->createChannels = AttrTo<uint32_t>(input, "createChannels");
-      descriptor->createWidth = AttrTo<uint32_t>(input, "createWidth");
-      descriptor->createHeight = AttrTo<uint32_t>(input, "createHeight");
-      v8::Local<v8::Object> createBackground = AttrAs<v8::Object>(input, "createBackground");
-      for (unsigned int i = 0; i < 4; i++) {
-        descriptor->createBackground[i] = AttrTo<double>(createBackground, i);
+      descriptor->createChannels = AttrAsUint32(input, "createChannels");
+      descriptor->createWidth = AttrAsUint32(input, "createWidth");
+      descriptor->createHeight = AttrAsUint32(input, "createHeight");
+      if (HasAttr(input, "createNoiseType")) {
+        descriptor->createNoiseType = AttrAsStr(input, "createNoiseType");
+        descriptor->createNoiseMean = AttrAsDouble(input, "createNoiseMean");
+        descriptor->createNoiseSigma = AttrAsDouble(input, "createNoiseSigma");
+      } else {
+        descriptor->createBackground = AttrAsVectorOfDouble(input, "createBackground");
       }
     }
+    // Limit input images to a given number of pixels, where pixels = width * height
+    descriptor->limitInputPixels = AttrAsUint32(input, "limitInputPixels");
+    // Allow switch from random to sequential access
+    descriptor->access = AttrAsBool(input, "sequentialRead") ? VIPS_ACCESS_SEQUENTIAL : VIPS_ACCESS_RANDOM;
     return descriptor;
   }
 
@@ -95,9 +154,25 @@ namespace sharp {
   bool IsWebp(std::string const &str) {
     return EndsWith(str, ".webp") || EndsWith(str, ".WEBP");
   }
+  bool IsGif(std::string const &str) {
+    return EndsWith(str, ".gif") || EndsWith(str, ".GIF");
+  }
+  bool IsJp2(std::string const &str) {
+    return EndsWith(str, ".jp2") || EndsWith(str, ".jpx") || EndsWith(str, ".j2k") || EndsWith(str, ".j2c")
+      || EndsWith(str, ".JP2") || EndsWith(str, ".JPX") || EndsWith(str, ".J2K") || EndsWith(str, ".J2C");
+  }
   bool IsTiff(std::string const &str) {
     return EndsWith(str, ".tif") || EndsWith(str, ".tiff") || EndsWith(str, ".TIF") || EndsWith(str, ".TIFF");
   }
+  bool IsHeic(std::string const &str) {
+    return EndsWith(str, ".heic") || EndsWith(str, ".HEIC");
+  }
+  bool IsHeif(std::string const &str) {
+    return EndsWith(str, ".heif") || EndsWith(str, ".HEIF") || IsHeic(str) || IsAvif(str);
+  }
+  bool IsAvif(std::string const &str) {
+    return EndsWith(str, ".avif") || EndsWith(str, ".AVIF");
+  }
   bool IsDz(std::string const &str) {
     return EndsWith(str, ".dzi") || EndsWith(str, ".DZI");
   }
@@ -119,43 +194,74 @@ namespace sharp {
       case ImageType::WEBP: id = "webp"; break;
       case ImageType::TIFF: id = "tiff"; break;
       case ImageType::GIF: id = "gif"; break;
+      case ImageType::JP2: id = "jp2"; break;
       case ImageType::SVG: id = "svg"; break;
+      case ImageType::HEIF: id = "heif"; break;
       case ImageType::PDF: id = "pdf"; break;
       case ImageType::MAGICK: id = "magick"; break;
       case ImageType::OPENSLIDE: id = "openslide"; break;
       case ImageType::PPM: id = "ppm"; break;
       case ImageType::FITS: id = "fits"; break;
-      case ImageType::VIPS: id = "v"; break;
+      case ImageType::EXR: id = "exr"; break;
+      case ImageType::VIPS: id = "vips"; break;
       case ImageType::RAW: id = "raw"; break;
       case ImageType::UNKNOWN: id = "unknown"; break;
+      case ImageType::MISSING: id = "missing"; break;
     }
     return id;
   }
 
+  /**
+   * Regenerate this table with something like:
+   *
+   * $ vips -l foreign | grep -i load | awk '{ print $2, $1; }'
+   *
+   * Plus a bit of editing.
+   */
+  std::map<std::string, ImageType> loaderToType = {
+    { "VipsForeignLoadJpegFile", ImageType::JPEG },
+    { "VipsForeignLoadJpegBuffer", ImageType::JPEG },
+    { "VipsForeignLoadPngFile", ImageType::PNG },
+    { "VipsForeignLoadPngBuffer", ImageType::PNG },
+    { "VipsForeignLoadWebpFile", ImageType::WEBP },
+    { "VipsForeignLoadWebpBuffer", ImageType::WEBP },
+    { "VipsForeignLoadTiffFile", ImageType::TIFF },
+    { "VipsForeignLoadTiffBuffer", ImageType::TIFF },
+    { "VipsForeignLoadGifFile", ImageType::GIF },
+    { "VipsForeignLoadGifBuffer", ImageType::GIF },
+    { "VipsForeignLoadNsgifFile", ImageType::GIF },
+    { "VipsForeignLoadNsgifBuffer", ImageType::GIF },
+    { "VipsForeignLoadJp2kBuffer", ImageType::JP2 },
+    { "VipsForeignLoadJp2kFile", ImageType::JP2 },
+    { "VipsForeignLoadSvgFile", ImageType::SVG },
+    { "VipsForeignLoadSvgBuffer", ImageType::SVG },
+    { "VipsForeignLoadHeifFile", ImageType::HEIF },
+    { "VipsForeignLoadHeifBuffer", ImageType::HEIF },
+    { "VipsForeignLoadPdfFile", ImageType::PDF },
+    { "VipsForeignLoadPdfBuffer", ImageType::PDF },
+    { "VipsForeignLoadMagickFile", ImageType::MAGICK },
+    { "VipsForeignLoadMagickBuffer", ImageType::MAGICK },
+    { "VipsForeignLoadMagick7File", ImageType::MAGICK },
+    { "VipsForeignLoadMagick7Buffer", ImageType::MAGICK },
+    { "VipsForeignLoadOpenslide", ImageType::OPENSLIDE },
+    { "VipsForeignLoadPpmFile", ImageType::PPM },
+    { "VipsForeignLoadFits", ImageType::FITS },
+    { "VipsForeignLoadOpenexr", ImageType::EXR },
+    { "VipsForeignLoadVips", ImageType::VIPS },
+    { "VipsForeignLoadVipsFile", ImageType::VIPS },
+    { "VipsForeignLoadRaw", ImageType::RAW }
+  };
+
   /*
     Determine image format of a buffer.
   */
   ImageType DetermineImageType(void *buffer, size_t const length) {
     ImageType imageType = ImageType::UNKNOWN;
     char const *load = vips_foreign_find_load_buffer(buffer, length);
-    if (load != NULL) {
-      std::string const loader = load;
-      if (EndsWith(loader, "JpegBuffer")) {
-        imageType = ImageType::JPEG;
-      } else if (EndsWith(loader, "PngBuffer")) {
-        imageType = ImageType::PNG;
-      } else if (EndsWith(loader, "WebpBuffer")) {
-        imageType = ImageType::WEBP;
-      } else if (EndsWith(loader, "TiffBuffer")) {
-        imageType = ImageType::TIFF;
-      } else if (EndsWith(loader, "GifBuffer")) {
-        imageType = ImageType::GIF;
-      } else if (EndsWith(loader, "SvgBuffer")) {
-        imageType = ImageType::SVG;
-      } else if (EndsWith(loader, "PdfBuffer")) {
-        imageType = ImageType::PDF;
-      } else if (EndsWith(loader, "MagickBuffer")) {
-        imageType = ImageType::MAGICK;
+    if (load != nullptr) {
+      auto it = loaderToType.find(load);
+      if (it != loaderToType.end()) {
+        imageType = it->second;
       }
     }
     return imageType;
@@ -168,52 +274,51 @@ namespace sharp {
     ImageType imageType = ImageType::UNKNOWN;
     char const *load = vips_foreign_find_load(file);
     if (load != nullptr) {
-      std::string const loader = load;
-      if (EndsWith(loader, "JpegFile")) {
-        imageType = ImageType::JPEG;
-      } else if (EndsWith(loader, "Png")) {
-        imageType = ImageType::PNG;
-      } else if (EndsWith(loader, "WebpFile")) {
-        imageType = ImageType::WEBP;
-      } else if (EndsWith(loader, "Openslide")) {
-        imageType = ImageType::OPENSLIDE;
-      } else if (EndsWith(loader, "TiffFile")) {
-        imageType = ImageType::TIFF;
-      } else if (EndsWith(loader, "GifFile")) {
-        imageType = ImageType::GIF;
-      } else if (EndsWith(loader, "SvgFile")) {
-        imageType = ImageType::SVG;
-      } else if (EndsWith(loader, "PdfFile")) {
-        imageType = ImageType::PDF;
-      } else if (EndsWith(loader, "Ppm")) {
-        imageType = ImageType::PPM;
-      } else if (EndsWith(loader, "Fits")) {
-        imageType = ImageType::FITS;
-      } else if (EndsWith(loader, "Vips")) {
-        imageType = ImageType::VIPS;
-      } else if (EndsWith(loader, "Magick") || EndsWith(loader, "MagickFile")) {
-        imageType = ImageType::MAGICK;
+      auto it = loaderToType.find(load);
+      if (it != loaderToType.end()) {
+        imageType = it->second;
+      }
+    } else {
+      if (EndsWith(vips::VError().what(), " does not exist\n")) {
+        imageType = ImageType::MISSING;
       }
     }
     return imageType;
   }
 
+  /*
+    Does this image type support multiple pages?
+  */
+  bool ImageTypeSupportsPage(ImageType imageType) {
+    return
+      imageType == ImageType::WEBP ||
+      imageType == ImageType::MAGICK ||
+      imageType == ImageType::GIF ||
+      imageType == ImageType::JP2 ||
+      imageType == ImageType::TIFF ||
+      imageType == ImageType::HEIF ||
+      imageType == ImageType::PDF;
+  }
+
   /*
     Open an image from the given InputDescriptor (filesystem, compressed buffer, raw pixel data)
   */
-  std::tuple<VImage, ImageType> OpenInput(InputDescriptor *descriptor, VipsAccess accessMethod) {
+  std::tuple<VImage, ImageType> OpenInput(InputDescriptor *descriptor) {
     VImage image;
     ImageType imageType;
-    if (descriptor->buffer != nullptr) {
+    if (descriptor->isBuffer) {
       if (descriptor->rawChannels > 0) {
         // Raw, uncompressed pixel data
         image = VImage::new_from_memory(descriptor->buffer, descriptor->bufferLength,
-          descriptor->rawWidth, descriptor->rawHeight, descriptor->rawChannels, VIPS_FORMAT_UCHAR);
+          descriptor->rawWidth, descriptor->rawHeight, descriptor->rawChannels, descriptor->rawDepth);
         if (descriptor->rawChannels < 3) {
           image.get_image()->Type = VIPS_INTERPRETATION_B_W;
         } else {
           image.get_image()->Type = VIPS_INTERPRETATION_sRGB;
         }
+        if (descriptor->rawPremultiplied) {
+          image = image.unpremultiply();
+        }
         imageType = ImageType::RAW;
       } else {
         // Compressed data
@@ -221,20 +326,33 @@ namespace sharp {
         if (imageType != ImageType::UNKNOWN) {
           try {
             vips::VOption *option = VImage::option()
-              ->set("access", accessMethod)
+              ->set("access", descriptor->access)
               ->set("fail", descriptor->failOnError);
+            if (imageType == ImageType::SVG) {
+              option->set("unlimited", TRUE);
+            }
             if (imageType == ImageType::SVG || imageType == ImageType::PDF) {
-              option->set("dpi", static_cast<double>(descriptor->density));
+              option->set("dpi", descriptor->density);
             }
             if (imageType == ImageType::MAGICK) {
               option->set("density", std::to_string(descriptor->density).data());
             }
+            if (ImageTypeSupportsPage(imageType)) {
+              option->set("n", descriptor->pages);
+              option->set("page", descriptor->page);
+            }
+            if (imageType == ImageType::OPENSLIDE) {
+              option->set("level", descriptor->level);
+            }
+            if (imageType == ImageType::TIFF) {
+              option->set("subifd", descriptor->subifd);
+            }
             image = VImage::new_from_buffer(descriptor->buffer, descriptor->bufferLength, nullptr, option);
             if (imageType == ImageType::SVG || imageType == ImageType::PDF || imageType == ImageType::MAGICK) {
-              SetDensity(image, descriptor->density);
+              image = SetDensity(image, descriptor->density);
             }
-          } catch (...) {
-            throw vips::VError("Input buffer has corrupt header");
+          } catch (vips::VError const &err) {
+            throw vips::VError(std::string("Input buffer has corrupt header: ") + err.what());
           }
         } else {
           throw vips::VError("Input buffer contains unsupported image format");
@@ -243,43 +361,84 @@ namespace sharp {
     } else {
       if (descriptor->createChannels > 0) {
         // Create new image
-        std::vector<double> background = {
-          descriptor->createBackground[0],
-          descriptor->createBackground[1],
-          descriptor->createBackground[2]
-        };
-        if (descriptor->createChannels == 4) {
-          background.push_back(descriptor->createBackground[3]);
+        if (descriptor->createNoiseType == "gaussian") {
+          int const channels = descriptor->createChannels;
+          image = VImage::new_matrix(descriptor->createWidth, descriptor->createHeight);
+          std::vector<VImage> bands = {};
+          bands.reserve(channels);
+          for (int _band = 0; _band < channels; _band++) {
+            bands.push_back(image.gaussnoise(
+              descriptor->createWidth,
+              descriptor->createHeight,
+              VImage::option()->set("mean", descriptor->createNoiseMean)->set("sigma", descriptor->createNoiseSigma)));
+          }
+          image = image.bandjoin(bands);
+          image = image.cast(VipsBandFormat::VIPS_FORMAT_UCHAR);
+          if (channels < 3) {
+            image = image.colourspace(VIPS_INTERPRETATION_B_W);
+          } else {
+            image = image.colourspace(VIPS_INTERPRETATION_sRGB);
+          }
+        } else {
+          std::vector<double> background = {
+            descriptor->createBackground[0],
+            descriptor->createBackground[1],
+            descriptor->createBackground[2]
+          };
+          if (descriptor->createChannels == 4) {
+            background.push_back(descriptor->createBackground[3]);
+          }
+          image = VImage::new_matrix(descriptor->createWidth, descriptor->createHeight).new_from_image(background);
         }
-        image = VImage::new_matrix(descriptor->createWidth, descriptor->createHeight).new_from_image(background);
         image.get_image()->Type = VIPS_INTERPRETATION_sRGB;
         imageType = ImageType::RAW;
       } else {
         // From filesystem
         imageType = DetermineImageType(descriptor->file.data());
+        if (imageType == ImageType::MISSING) {
+          throw vips::VError("Input file is missing");
+        }
         if (imageType != ImageType::UNKNOWN) {
           try {
             vips::VOption *option = VImage::option()
-              ->set("access", accessMethod)
+              ->set("access", descriptor->access)
               ->set("fail", descriptor->failOnError);
+            if (imageType == ImageType::SVG) {
+              option->set("unlimited", TRUE);
+            }
             if (imageType == ImageType::SVG || imageType == ImageType::PDF) {
-              option->set("dpi", static_cast<double>(descriptor->density));
+              option->set("dpi", descriptor->density);
             }
             if (imageType == ImageType::MAGICK) {
               option->set("density", std::to_string(descriptor->density).data());
             }
+            if (ImageTypeSupportsPage(imageType)) {
+              option->set("n", descriptor->pages);
+              option->set("page", descriptor->page);
+            }
+            if (imageType == ImageType::OPENSLIDE) {
+              option->set("level", descriptor->level);
+            }
+            if (imageType == ImageType::TIFF) {
+              option->set("subifd", descriptor->subifd);
+            }
             image = VImage::new_from_file(descriptor->file.data(), option);
             if (imageType == ImageType::SVG || imageType == ImageType::PDF || imageType == ImageType::MAGICK) {
-              SetDensity(image, descriptor->density);
+              image = SetDensity(image, descriptor->density);
             }
-          } catch (...) {
-            throw vips::VError("Input file has corrupt header");
+          } catch (vips::VError const &err) {
+            throw vips::VError(std::string("Input file has corrupt header: ") + err.what());
           }
         } else {
-          throw vips::VError("Input file is missing or of an unsupported image format");
+          throw vips::VError("Input file contains unsupported image format");
         }
       }
     }
+    // Limit input images to a given number of pixels, where pixels = width * height
+    if (descriptor->limitInputPixels > 0 &&
+      static_cast<uint64_t>(image.width() * image.height()) > static_cast<uint64_t>(descriptor->limitInputPixels)) {
+      throw vips::VError("Input image exceeds pixel limit");
+    }
     return std::make_tuple(image, imageType);
   }
 
@@ -295,12 +454,7 @@ namespace sharp {
     Uses colour space interpretation with number of channels to guess this.
   */
   bool HasAlpha(VImage image) {
-    int const bands = image.bands();
-    VipsInterpretation const interpretation = image.interpretation();
-    return (
-      (bands == 2 && interpretation == VIPS_INTERPRETATION_B_W) ||
-      (bands == 4 && interpretation != VIPS_INTERPRETATION_CMYK) ||
-      (bands == 5 && interpretation == VIPS_INTERPRETATION_CMYK));
+    return image.has_alpha();
   }
 
   /*
@@ -317,15 +471,62 @@ namespace sharp {
   /*
     Set EXIF Orientation of image.
   */
-  void SetExifOrientation(VImage image, int const orientation) {
-    image.set(VIPS_META_ORIENTATION, orientation);
+  VImage SetExifOrientation(VImage image, int const orientation) {
+    VImage copy = image.copy();
+    copy.set(VIPS_META_ORIENTATION, orientation);
+    return copy;
   }
 
   /*
     Remove EXIF Orientation from image.
   */
-  void RemoveExifOrientation(VImage image) {
-    vips_image_remove(image.get_image(), VIPS_META_ORIENTATION);
+  VImage RemoveExifOrientation(VImage image) {
+    VImage copy = image.copy();
+    copy.remove(VIPS_META_ORIENTATION);
+    return copy;
+  }
+
+  /*
+    Set animation properties if necessary.
+    Non-provided properties will be loaded from image.
+  */
+  VImage SetAnimationProperties(VImage image, int pageHeight, std::vector<int> delay, int loop) {
+    bool hasDelay = delay.size() != 1 || delay.front() != -1;
+
+    if (pageHeight == 0 && image.get_typeof(VIPS_META_PAGE_HEIGHT) == G_TYPE_INT) {
+      pageHeight = image.get_int(VIPS_META_PAGE_HEIGHT);
+    }
+
+    if (!hasDelay && image.get_typeof("delay") == VIPS_TYPE_ARRAY_INT) {
+      delay = image.get_array_int("delay");
+      hasDelay = true;
+    }
+
+    if (loop == -1 && image.get_typeof("loop") == G_TYPE_INT) {
+      loop = image.get_int("loop");
+    }
+
+    if (pageHeight == 0) return image;
+
+    // It is necessary to create the copy as otherwise, pageHeight will be ignored!
+    VImage copy = image.copy();
+
+    copy.set(VIPS_META_PAGE_HEIGHT, pageHeight);
+    if (hasDelay) copy.set("delay", delay);
+    if (loop != -1) copy.set("loop", loop);
+
+    return copy;
+  }
+
+  /*
+    Remove animation properties from image.
+  */
+  VImage RemoveAnimationProperties(VImage image) {
+    VImage copy = image.copy();
+    copy.remove(VIPS_META_PAGE_HEIGHT);
+    copy.remove("delay");
+    copy.remove("loop");
+    return copy;
   }
 
   /*
@@ -345,40 +546,42 @@ namespace sharp {
   /*
     Set pixels/mm resolution based on a pixels/inch density.
   */
-  void SetDensity(VImage image, const int density) {
-    const double pixelsPerMm = static_cast<double>(density) / 25.4;
-    image.set("Xres", pixelsPerMm);
-    image.set("Yres", pixelsPerMm);
-    image.set(VIPS_META_RESOLUTION_UNIT, "in");
+  VImage SetDensity(VImage image, const double density) {
+    const double pixelsPerMm = density / 25.4;
+    VImage copy = image.copy();
+    copy.get_image()->Xres = pixelsPerMm;
+    copy.get_image()->Yres = pixelsPerMm;
+    return copy;
   }
 
   /*
     Check the proposed format supports the current dimensions.
   */
   void AssertImageTypeDimensions(VImage image, ImageType const imageType) {
+    const int height = image.get_typeof(VIPS_META_PAGE_HEIGHT) == G_TYPE_INT
+      ? image.get_int(VIPS_META_PAGE_HEIGHT)
+      : image.height();
     if (imageType == ImageType::JPEG) {
-      if (image.width() > 65535 || image.height() > 65535) {
+      if (image.width() > 65535 || height > 65535) {
         throw vips::VError("Processed image is too large for the JPEG format");
       }
-    } else if (imageType == ImageType::PNG) {
-      if (image.width() > 2147483647 || image.height() > 2147483647) {
-        throw vips::VError("Processed image is too large for the PNG format");
-      }
     } else if (imageType == ImageType::WEBP) {
-      if (image.width() > 16383 || image.height() > 16383) {
+      if (image.width() > 16383 || height > 16383) {
         throw vips::VError("Processed image is too large for the WebP format");
       }
+    } else if (imageType == ImageType::GIF) {
+      if (image.width() > 65535 || height > 65535) {
+        throw vips::VError("Processed image is too large for the GIF format");
+      }
     }
   }
 
   /*
     Called when a Buffer undergoes GC, required to support mixed runtime libraries in Windows
   */
-  void FreeCallback(char* data, void* hint) {
-    if (data != nullptr) {
-      g_free(data);
-    }
-  }
+  std::function<void(void*, char*)> FreeCallback = [](void*, char* data) {
+    g_free(data);
+  };
 
   /*
     Temporary buffer of warnings
@@ -407,6 +610,33 @@ namespace sharp {
     return warning;
   }
 
+  /*
+    Attach an event listener for progress updates, used to detect timeout
+  */
+  void SetTimeout(VImage image, int const seconds) {
+    if (seconds > 0) {
+      VipsImage *im = image.get_image();
+      if (im->progress_signal == NULL) {
+        int *timeout = VIPS_NEW(im, int);
+        *timeout = seconds;
+        g_signal_connect(im, "eval", G_CALLBACK(VipsProgressCallBack), timeout);
+        vips_image_set_progress(im, TRUE);
+      }
+    }
+  }
+
+  /*
+    Event listener for progress updates, used to detect timeout
+  */
+  void VipsProgressCallBack(VipsImage *im, VipsProgress *progress, int *timeout) {
+    // printf("VipsProgressCallBack progress=%d run=%d timeout=%d\n", progress->percent, progress->run, *timeout);
+    if (*timeout > 0 && progress->run >= *timeout) {
+      vips_image_set_kill(im, TRUE);
+      vips_error("timeout", "%d%% complete", progress->percent);
+      *timeout = 0;
+    }
+  }
+
   /*
     Calculate the (left, top) coordinates of the output image
     within the input image, applying the given gravity during an embed.
@@ -526,26 +756,18 @@ namespace sharp {
     int top = 0;
 
     // assign only if valid
-    if (x >= 0 && x < (inWidth - outWidth)) {
+    if (x < (inWidth - outWidth)) {
       left = x;
     } else if (x >= (inWidth - outWidth)) {
       left = inWidth - outWidth;
     }
 
-    if (y >= 0 && y < (inHeight - outHeight)) {
+    if (y < (inHeight - outHeight)) {
       top = y;
     } else if (y >= (inHeight - outHeight)) {
       top = inHeight - outHeight;
     }
 
-    // the resulting left and top could have been outside the image after calculation from bottom/right edges
-    if (left < 0) {
-      left = 0;
-    }
-    if (top < 0) {
-      top = 0;
-    }
-
     return std::make_tuple(left, top);
   }
 
@@ -583,17 +805,79 @@ namespace sharp {
   /*
     Convert RGBA value to another colourspace
   */
-  std::vector<double> GetRgbaAsColourspace(std::vector<double> const rgba, VipsInterpretation const interpretation) {
+  std::vector<double> GetRgbaAsColourspace(std::vector<double> const rgba,
+    VipsInterpretation const interpretation, bool premultiply) {
     int const bands = static_cast<int>(rgba.size());
-    if (bands < 3 || interpretation == VIPS_INTERPRETATION_sRGB || interpretation == VIPS_INTERPRETATION_RGB) {
+    if (bands < 3) {
       return rgba;
-    } else {
-      VImage pixel = VImage::new_matrix(1, 1);
-      pixel.set("bands", bands);
-      pixel = pixel.new_from_image(rgba);
-      pixel = pixel.colourspace(interpretation, VImage::option()->set("source_space", VIPS_INTERPRETATION_sRGB));
-      return pixel(0, 0);
     }
+    VImage pixel = VImage::new_matrix(1, 1);
+    pixel.set("bands", bands);
+    pixel = pixel
+      .new_from_image(rgba)
+      .colourspace(interpretation, VImage::option()->set("source_space", VIPS_INTERPRETATION_sRGB));
+    if (premultiply) {
+      pixel = pixel.premultiply();
+    }
+    return pixel(0, 0);
+  }
+
+  /*
+    Apply the alpha channel to a given colour
+  */
+  std::tuple<VImage, std::vector<double>> ApplyAlpha(VImage image, std::vector<double> colour, bool premultiply) {
+    // Scale up 8-bit values to match 16-bit input image
+    double const multiplier = sharp::Is16Bit(image.interpretation()) ? 256.0 : 1.0;
+    // Create alphaColour colour
+    std::vector<double> alphaColour;
+    if (image.bands() > 2) {
+      alphaColour = {
+        multiplier * colour[0],
+        multiplier * colour[1],
+        multiplier * colour[2]
+      };
+    } else {
+      // Convert sRGB to greyscale
+      alphaColour = { multiplier * (
+        0.2126 * colour[0] +
+        0.7152 * colour[1] +
+        0.0722 * colour[2])
+      };
+    }
+    // Add alpha channel to alphaColour colour
+    if (colour[3] < 255.0 || HasAlpha(image)) {
+      alphaColour.push_back(colour[3] * multiplier);
+    }
+    // Ensure alphaColour colour uses correct colourspace
+    alphaColour = sharp::GetRgbaAsColourspace(alphaColour, image.interpretation(), premultiply);
+    // Add non-transparent alpha channel, if required
+    if (colour[3] < 255.0 && !HasAlpha(image)) {
+      image = image.bandjoin(
+        VImage::new_matrix(image.width(), image.height()).new_from_image(255 * multiplier));
+    }
+    return std::make_tuple(image, alphaColour);
+  }
+
+  /*
+    Removes alpha channel, if any.
+  */
+  VImage RemoveAlpha(VImage image) {
+    if (HasAlpha(image)) {
+      image = image.extract_band(0, VImage::option()->set("n", image.bands() - 1));
+    }
+    return image;
+  }
+
+  /*
+    Ensures alpha channel, if missing.
+  */
+  VImage EnsureAlpha(VImage image, double const value) {
+    if (!HasAlpha(image)) {
+      std::vector<double> alpha;
+      alpha.push_back(value * sharp::MaximumImageAlpha(image.interpretation()));
+      image = image.bandjoin_const(alpha);
+    }
+    return image;
   }
 
 }  // namespace sharp

src/common.h

@@ -1,4 +1,4 @@
-// Copyright 2013, 2014, 2015, 2016, 2017 Lovell Fuller and contributors.
+// Copyright 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Lovell Fuller and contributors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -19,23 +19,24 @@
 #include <tuple>
 #include <vector>
 
-#include <node.h>
-#include <nan.h>
+#include <napi.h>
 #include <vips/vips8>
 
 // Verify platform and compiler compatibility
 
-#if (VIPS_MAJOR_VERSION < 8 || (VIPS_MAJOR_VERSION == 8 && VIPS_MINOR_VERSION < 6))
-#error libvips version 8.6.1+ is required - see sharp.pixelplumbing.com/page/install
+#if (VIPS_MAJOR_VERSION < 8) || \
+  (VIPS_MAJOR_VERSION == 8 && VIPS_MINOR_VERSION < 11) || \
+  (VIPS_MAJOR_VERSION == 8 && VIPS_MINOR_VERSION == 11 && VIPS_MICRO_VERSION < 3)
+#error "libvips version 8.11.3+ is required - please see https://sharp.pixelplumbing.com/install"
 #endif
 
 #if ((!defined(__clang__)) && defined(__GNUC__) && (__GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 6)))
-#error GCC version 4.6+ is required for C++11 features - see sharp.pixelplumbing.com/page/install#prerequisites
+#error "GCC version 4.6+ is required for C++11 features - please see https://sharp.pixelplumbing.com/install"
 #endif
 
 #if (defined(__clang__) && defined(__has_feature))
 #if (!__has_feature(cxx_range_for))
-#error clang version 3.0+ is required for C++11 features - see sharp.pixelplumbing.com/page/install#prerequisites
+#error "clang version 3.0+ is required for C++11 features - please see https://sharp.pixelplumbing.com/install"
 #endif
 #endif
 
@@ -43,71 +44,93 @@ using vips::VImage;
 
 namespace sharp {
 
-  struct InputDescriptor {
+  struct InputDescriptor {  // NOLINT(runtime/indentation_namespace)
     std::string name;
     std::string file;
     char *buffer;
     bool failOnError;
+    int limitInputPixels;
+    VipsAccess access;
     size_t bufferLength;
-    int density;
+    bool isBuffer;
+    double density;
+    VipsBandFormat rawDepth;
     int rawChannels;
     int rawWidth;
     int rawHeight;
+    bool rawPremultiplied;
+    int pages;
+    int page;
+    int level;
+    int subifd;
     int createChannels;
     int createWidth;
     int createHeight;
-    double createBackground[4];
+    std::vector<double> createBackground;
+    std::string createNoiseType;
+    double createNoiseMean;
+    double createNoiseSigma;
 
     InputDescriptor():
       buffer(nullptr),
-      failOnError(FALSE),
+      failOnError(TRUE),
+      limitInputPixels(0x3FFF * 0x3FFF),
+      access(VIPS_ACCESS_RANDOM),
       bufferLength(0),
-      density(72),
+      isBuffer(FALSE),
+      density(72.0),
+      rawDepth(VIPS_FORMAT_UCHAR),
       rawChannels(0),
       rawWidth(0),
       rawHeight(0),
+      rawPremultiplied(false),
+      pages(1),
+      page(0),
+      level(0),
+      subifd(-1),
       createChannels(0),
       createWidth(0),
-      createHeight(0) {
-        createBackground[0] = 0.0;
-        createBackground[1] = 0.0;
-        createBackground[2] = 0.0;
-        createBackground[3] = 255.0;
-      }
+      createHeight(0),
+      createBackground{ 0.0, 0.0, 0.0, 255.0 },
+      createNoiseMean(0.0),
+      createNoiseSigma(0.0) {}
   };
 
-  // Convenience methods to access the attributes of a v8::Object
-  bool HasAttr(v8::Handle<v8::Object> obj, std::string attr);
-  std::string AttrAsStr(v8::Handle<v8::Object> obj, std::string attr);
-  template<typename T> v8::Local<T> AttrAs(v8::Handle<v8::Object> obj, std::string attr) {
-    return Nan::Get(obj, Nan::New(attr).ToLocalChecked()).ToLocalChecked().As<T>();
-  }
-  template<typename T> T AttrTo(v8::Handle<v8::Object> obj, std::string attr) {
-    return Nan::To<T>(Nan::Get(obj, Nan::New(attr).ToLocalChecked()).ToLocalChecked()).FromJust();
-  }
-  template<typename T> T AttrTo(v8::Handle<v8::Object> obj, int attr) {
-    return Nan::To<T>(Nan::Get(obj, attr).ToLocalChecked()).FromJust();
-  }
+  // Convenience methods to access the attributes of a Napi::Object
+  bool HasAttr(Napi::Object obj, std::string attr);
+  std::string AttrAsStr(Napi::Object obj, std::string attr);
+  std::string AttrAsStr(Napi::Object obj, unsigned int const attr);
+  uint32_t AttrAsUint32(Napi::Object obj, std::string attr);
+  int32_t AttrAsInt32(Napi::Object obj, std::string attr);
+  int32_t AttrAsInt32(Napi::Object obj, unsigned int const attr);
+  double AttrAsDouble(Napi::Object obj, std::string attr);
+  double AttrAsDouble(Napi::Object obj, unsigned int const attr);
+  bool AttrAsBool(Napi::Object obj, std::string attr);
+  std::vector<double> AttrAsVectorOfDouble(Napi::Object obj, std::string attr);
+  std::vector<int32_t> AttrAsInt32Vector(Napi::Object obj, std::string attr);
 
-  // Create an InputDescriptor instance from a v8::Object describing an input image
-  InputDescriptor* CreateInputDescriptor(
-    v8::Handle<v8::Object> input, std::vector<v8::Local<v8::Object>> &buffersToPersist);
+  // Create an InputDescriptor instance from a Napi::Object describing an input image
+  InputDescriptor* CreateInputDescriptor(Napi::Object input);
 
   enum class ImageType {
     JPEG,
     PNG,
     WEBP,
+    JP2,
     TIFF,
     GIF,
     SVG,
+    HEIF,
     PDF,
     MAGICK,
     OPENSLIDE,
     PPM,
     FITS,
+    EXR,
     VIPS,
     RAW,
-    UNKNOWN
+    UNKNOWN,
+    MISSING
   };
 
   // How many tasks are in the queue?
@@ -120,7 +143,12 @@ namespace sharp {
   bool IsJpeg(std::string const &str);
   bool IsPng(std::string const &str);
   bool IsWebp(std::string const &str);
+  bool IsJp2(std::string const &str);
+  bool IsGif(std::string const &str);
   bool IsTiff(std::string const &str);
+  bool IsHeic(std::string const &str);
+  bool IsHeif(std::string const &str);
+  bool IsAvif(std::string const &str);
   bool IsDz(std::string const &str);
   bool IsDzZip(std::string const &str);
   bool IsV(std::string const &str);
@@ -140,10 +168,15 @@ namespace sharp {
   */
   ImageType DetermineImageType(char const *file);
 
+  /*
+    Does this image type support multiple pages?
+  */
+  bool ImageTypeSupportsPage(ImageType imageType);
+
   /*
     Open an image from the given InputDescriptor (filesystem, compressed buffer, raw pixel data)
   */
-  std::tuple<VImage, ImageType> OpenInput(InputDescriptor *descriptor, VipsAccess accessMethod);
+  std::tuple<VImage, ImageType> OpenInput(InputDescriptor *descriptor);
 
   /*
     Does this image have an embedded profile?
@@ -164,12 +197,23 @@ namespace sharp {
   /*
     Set EXIF Orientation of image.
   */
-  void SetExifOrientation(VImage image, int const orientation);
+  VImage SetExifOrientation(VImage image, int const orientation);
 
   /*
     Remove EXIF Orientation from image.
   */
-  void RemoveExifOrientation(VImage image);
+  VImage RemoveExifOrientation(VImage image);
+
+  /*
+    Set animation properties if necessary.
+    Non-provided properties will be loaded from image.
+  */
+  VImage SetAnimationProperties(VImage image, int pageHeight, std::vector<int> delay, int loop);
+
+  /*
+    Remove animation properties from image.
+  */
+  VImage RemoveAnimationProperties(VImage image);
 
   /*
     Does this image have a non-default density?
@@ -184,7 +228,7 @@ namespace sharp {
   /*
     Set pixels/mm resolution based on a pixels/inch density.
   */
-  void SetDensity(VImage image, const int density);
+  VImage SetDensity(VImage image, const double density);
 
   /*
     Check the proposed format supports the current dimensions.
@@ -194,7 +238,7 @@ namespace sharp {
   /*
     Called when a Buffer undergoes GC, required to support mixed runtime libraries in Windows
   */
-  void FreeCallback(char* data, void* hint);
+  extern std::function<void(void*, char*)> FreeCallback;
 
   /*
     Called with warnings from the glib-registered "VIPS" domain
@@ -206,6 +250,16 @@ namespace sharp {
   */
   std::string VipsWarningPop();
 
+  /*
+    Attach an event listener for progress updates, used to detect timeout
+  */
+  void SetTimeout(VImage image, int const timeoutSeconds);
+
+  /*
+    Event listener for progress updates, used to detect timeout
+  */
+  void VipsProgressCallBack(VipsImage *image, VipsProgress *progress, int *timeoutSeconds);
+
   /*
     Calculate the (left, top) coordinates of the output image
     within the input image, applying the given gravity during an embed.
@@ -251,7 +305,23 @@ namespace sharp {
   /*
     Convert RGBA value to another colourspace
   */
-  std::vector<double> GetRgbaAsColourspace(std::vector<double> const rgba, VipsInterpretation const interpretation);
+  std::vector<double> GetRgbaAsColourspace(std::vector<double> const rgba,
+    VipsInterpretation const interpretation, bool premultiply);
+
+  /*
+    Apply the alpha channel to a given colour
+   */
+  std::tuple<VImage, std::vector<double>> ApplyAlpha(VImage image, std::vector<double> colour, bool premultiply);
+
+  /*
+    Removes alpha channel, if any.
+  */
+  VImage RemoveAlpha(VImage image);
+
+  /*
+    Ensures alpha channel, if missing.
+  */
+  VImage EnsureAlpha(VImage image, double const value);
 
 }  // namespace sharp
 

src/libvips/cplusplus/VConnection.cpp

@@ -0,0 +1,152 @@
+/* Object part of the VSource and VTarget class
+ */
+
+/*
+
+    Copyright (C) 1991-2001 The National Gallery
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+    02110-1301  USA
+
+ */
+
+/*
+
+    These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
+
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif /*HAVE_CONFIG_H*/
+#include <vips/intl.h>
+
+#include <vips/vips8>
+
+#include <vips/debug.h>
+
+/*
+#define VIPS_DEBUG
+#define VIPS_DEBUG_VERBOSE
+ */
+
+VIPS_NAMESPACE_START
+
+VSource 
+VSource::new_from_descriptor( int descriptor )
+{
+	VipsSource *input;
+
+	if( !(input = vips_source_new_from_descriptor( descriptor )) )
+		throw VError();
+
+	VSource out( input ); 
+
+	return( out ); 
+}
+
+VSource 
+VSource::new_from_file( const char *filename )
+{
+	VipsSource *input;
+
+	if( !(input = vips_source_new_from_file( filename )) )
+		throw VError();
+
+	VSource out( input ); 
+
+	return( out ); 
+}
+
+VSource 
+VSource::new_from_blob( VipsBlob *blob )
+{
+	VipsSource *input;
+
+	if( !(input = vips_source_new_from_blob( blob )) )
+		throw VError();
+
+	VSource out( input ); 
+
+	return( out ); 
+}
+
+VSource 
+VSource::new_from_memory( const void *data, 
+	size_t size )
+{
+	VipsSource *input;
+
+	if( !(input = vips_source_new_from_memory( data, size )) )
+		throw VError();
+
+	VSource out( input ); 
+
+	return( out ); 
+}
+
+VSource 
+VSource::new_from_options( const char *options )
+{
+	VipsSource *input;
+
+	if( !(input = vips_source_new_from_options( options )) )
+		throw VError();
+
+	VSource out( input ); 
+
+	return( out ); 
+}
+
+VTarget 
+VTarget::new_to_descriptor( int descriptor )
+{
+	VipsTarget *output;
+
+	if( !(output = vips_target_new_to_descriptor( descriptor )) )
+		throw VError();
+
+	VTarget out( output ); 
+
+	return( out ); 
+}
+
+VTarget 
+VTarget::new_to_file( const char *filename )
+{
+	VipsTarget *output;
+
+	if( !(output = vips_target_new_to_file( filename )) )
+		throw VError();
+
+	VTarget out( output ); 
+
+	return( out ); 
+}
+
+VTarget 
+VTarget::new_to_memory()
+{
+	VipsTarget *output;
+
+	if( !(output = vips_target_new_to_memory()) )
+		throw VError();
+
+	VTarget out( output ); 
+
+	return( out ); 
+}
+
+VIPS_NAMESPACE_END

src/libvips/cplusplus/VError.cpp

@@ -32,8 +32,6 @@
 #endif /*HAVE_CONFIG_H*/
 #include <vips/intl.h>
 
-#include <iostream>
-
 #include <vips/vips8>
 
 VIPS_NAMESPACE_START

src/libvips/cplusplus/VInterpolate.cpp

@@ -60,17 +60,4 @@ VInterpolate::new_from_name( const char *name, VOption *options )
 	return( out ); 
 }
 
-VOption *
-VOption::set( const char *name, VInterpolate value )
-{
-	Pair *pair = new Pair( name );
-
-	pair->input = true;
-	g_value_init( &pair->value, VIPS_TYPE_INTERPOLATE );
-	g_value_set_object( &pair->value, value.get_interpolate() );
-	options.push_back( pair );
-
-	return( this );
-}
-
 VIPS_NAMESPACE_END

src/metadata.cc

@@ -1,4 +1,4 @@
-// Copyright 2013, 2014, 2015, 2016, 2017 Lovell Fuller and contributors.
+// Copyright 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Lovell Fuller and contributors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -15,28 +15,16 @@
 #include <numeric>
 #include <vector>
 
-#include <node.h>
-#include <nan.h>
+#include <napi.h>
 #include <vips/vips8>
 
 #include "common.h"
 #include "metadata.h"
 
-class MetadataWorker : public Nan::AsyncWorker {
+class MetadataWorker : public Napi::AsyncWorker {
  public:
-  MetadataWorker(
-    Nan::Callback *callback, MetadataBaton *baton, Nan::Callback *debuglog,
-    std::vector<v8::Local<v8::Object>> const buffersToPersist) :
-    Nan::AsyncWorker(callback, "sharp:MetadataWorker"),
-    baton(baton), debuglog(debuglog),
-    buffersToPersist(buffersToPersist) {
-    // Protect Buffer objects from GC, keyed on index
-    std::accumulate(buffersToPersist.begin(), buffersToPersist.end(), 0,
-      [this](uint32_t index, v8::Local<v8::Object> const buffer) -> uint32_t {
-        SaveToPersistent(index, buffer);
-        return index + 1;
-      });
-  }
+  MetadataWorker(Napi::Function callback, MetadataBaton *baton, Napi::Function debuglog) :
+    Napi::AsyncWorker(callback), baton(baton), debuglog(Napi::Persistent(debuglog)) {}
   ~MetadataWorker() {}
 
   void Execute() {
@@ -46,7 +34,7 @@ class MetadataWorker : public Nan::AsyncWorker {
     vips::VImage image;
     sharp::ImageType imageType = sharp::ImageType::UNKNOWN;
     try {
-      std::tie(image, imageType) = OpenInput(baton->input, VIPS_ACCESS_SEQUENTIAL);
+      std::tie(image, imageType) = OpenInput(baton->input);
     } catch (vips::VError const &err) {
       (baton->err).append(err.what());
     }
@@ -62,7 +50,49 @@ class MetadataWorker : public Nan::AsyncWorker {
       if (sharp::HasDensity(image)) {
         baton->density = sharp::GetDensity(image);
       }
+      if (image.get_typeof("jpeg-chroma-subsample") == VIPS_TYPE_REF_STRING) {
+        baton->chromaSubsampling = image.get_string("jpeg-chroma-subsample");
+      }
+      if (image.get_typeof("interlaced") == G_TYPE_INT) {
+        baton->isProgressive = image.get_int("interlaced") == 1;
+      }
+      if (image.get_typeof("palette-bit-depth") == G_TYPE_INT) {
+        baton->paletteBitDepth = image.get_int("palette-bit-depth");
+      }
+      if (image.get_typeof(VIPS_META_N_PAGES) == G_TYPE_INT) {
+        baton->pages = image.get_int(VIPS_META_N_PAGES);
+      }
+      if (image.get_typeof(VIPS_META_PAGE_HEIGHT) == G_TYPE_INT) {
+        baton->pageHeight = image.get_int(VIPS_META_PAGE_HEIGHT);
+      }
+      if (image.get_typeof("loop") == G_TYPE_INT) {
+        baton->loop = image.get_int("loop");
+      }
+      if (image.get_typeof("delay") == VIPS_TYPE_ARRAY_INT) {
+        baton->delay = image.get_array_int("delay");
+      }
+      if (image.get_typeof("heif-primary") == G_TYPE_INT) {
+        baton->pagePrimary = image.get_int("heif-primary");
+      }
+      if (image.get_typeof("heif-compression") == VIPS_TYPE_REF_STRING) {
+        baton->compression = image.get_string("heif-compression");
+      }
+      if (image.get_typeof("openslide.level-count") == VIPS_TYPE_REF_STRING) {
+        int const levels = std::stoi(image.get_string("openslide.level-count"));
+        for (int l = 0; l < levels; l++) {
+          std::string prefix = "openslide.level[" + std::to_string(l) + "].";
+          int const width = std::stoi(image.get_string((prefix + "width").data()));
+          int const height = std::stoi(image.get_string((prefix + "height").data()));
+          baton->levels.push_back(std::pair<int, int>(width, height));
+        }
+      }
+      if (image.get_typeof(VIPS_META_N_SUBIFDS) == G_TYPE_INT) {
+        baton->subifds = image.get_int(VIPS_META_N_SUBIFDS);
+      }
       baton->hasProfile = sharp::HasProfile(image);
+      if (image.get_typeof("background") == VIPS_TYPE_ARRAY_DOUBLE) {
+        baton->background = image.get_array_double("background");
+      }
       // Derived attributes
       baton->hasAlpha = sharp::HasAlpha(image);
       baton->orientation = sharp::ExifOrientation(image);
@@ -83,9 +113,9 @@ class MetadataWorker : public Nan::AsyncWorker {
         baton->iccLength = iccLength;
       }
       // IPTC
-      if (image.get_typeof(VIPS_META_IPCT_NAME) == VIPS_TYPE_BLOB) {
+      if (image.get_typeof(VIPS_META_IPTC_NAME) == VIPS_TYPE_BLOB) {
         size_t iptcLength;
-        void const *iptc = image.get_blob(VIPS_META_IPCT_NAME, &iptcLength);
+        void const *iptc = image.get_blob(VIPS_META_IPTC_NAME, &iptcLength);
         baton->iptc = static_cast<char *>(g_malloc(iptcLength));
         memcpy(baton->iptc, iptc, iptcLength);
         baton->iptcLength = iptcLength;
@@ -98,6 +128,14 @@ class MetadataWorker : public Nan::AsyncWorker {
         memcpy(baton->xmp, xmp, xmpLength);
         baton->xmpLength = xmpLength;
       }
+      // TIFFTAG_PHOTOSHOP
+      if (image.get_typeof(VIPS_META_PHOTOSHOP_NAME) == VIPS_TYPE_BLOB) {
+        size_t tifftagPhotoshopLength;
+        void const *tifftagPhotoshop = image.get_blob(VIPS_META_PHOTOSHOP_NAME, &tifftagPhotoshopLength);
+        baton->tifftagPhotoshop = static_cast<char *>(g_malloc(tifftagPhotoshopLength));
+        memcpy(baton->tifftagPhotoshop, tifftagPhotoshop, tifftagPhotoshopLength);
+        baton->tifftagPhotoshopLength = tifftagPhotoshopLength;
+      }
     }
 
     // Clean up
@@ -105,102 +143,143 @@ class MetadataWorker : public Nan::AsyncWorker {
     vips_thread_shutdown();
   }
 
-  void HandleOKCallback() {
-    using Nan::New;
-    using Nan::Set;
-    Nan::HandleScope();
-
-    v8::Local<v8::Value> argv[2] = { Nan::Null(), Nan::Null() };
-    if (!baton->err.empty()) {
-      argv[0] = Nan::Error(baton->err.data());
-    } else {
-      // Metadata Object
-      v8::Local<v8::Object> info = New<v8::Object>();
-      Set(info, New("format").ToLocalChecked(), New<v8::String>(baton->format).ToLocalChecked());
-      Set(info, New("width").ToLocalChecked(), New<v8::Uint32>(baton->width));
-      Set(info, New("height").ToLocalChecked(), New<v8::Uint32>(baton->height));
-      Set(info, New("space").ToLocalChecked(), New<v8::String>(baton->space).ToLocalChecked());
-      Set(info, New("channels").ToLocalChecked(), New<v8::Uint32>(baton->channels));
-      Set(info, New("depth").ToLocalChecked(), New<v8::String>(baton->depth).ToLocalChecked());
-      if (baton->density > 0) {
-        Set(info, New("density").ToLocalChecked(), New<v8::Uint32>(baton->density));
-      }
-      Set(info, New("hasProfile").ToLocalChecked(), New<v8::Boolean>(baton->hasProfile));
-      Set(info, New("hasAlpha").ToLocalChecked(), New<v8::Boolean>(baton->hasAlpha));
-      if (baton->orientation > 0) {
-        Set(info, New("orientation").ToLocalChecked(), New<v8::Uint32>(baton->orientation));
-      }
-      if (baton->exifLength > 0) {
-        Set(info,
-          New("exif").ToLocalChecked(),
-          Nan::NewBuffer(baton->exif, baton->exifLength, sharp::FreeCallback, nullptr).ToLocalChecked());
-      }
-      if (baton->iccLength > 0) {
-        Set(info,
-          New("icc").ToLocalChecked(),
-          Nan::NewBuffer(baton->icc, baton->iccLength, sharp::FreeCallback, nullptr).ToLocalChecked());
-      }
-      if (baton->iptcLength > 0) {
-        Set(info,
-          New("iptc").ToLocalChecked(),
-          Nan::NewBuffer(baton->iptc, baton->iptcLength, sharp::FreeCallback, nullptr).ToLocalChecked());
-      }
-      if (baton->xmpLength > 0) {
-        Set(info,
-          New("xmp").ToLocalChecked(),
-          Nan::NewBuffer(baton->xmp, baton->xmpLength, sharp::FreeCallback, nullptr).ToLocalChecked());
-      }
-      argv[1] = info;
-    }
-
-    // Dispose of Persistent wrapper around input Buffers so they can be garbage collected
-    std::accumulate(buffersToPersist.begin(), buffersToPersist.end(), 0,
-      [this](uint32_t index, v8::Local<v8::Object> const buffer) -> uint32_t {
-        GetFromPersistent(index);
-        return index + 1;
-      });
-    delete baton->input;
-    delete baton;
+  void OnOK() {
+    Napi::Env env = Env();
+    Napi::HandleScope scope(env);
 
     // Handle warnings
     std::string warning = sharp::VipsWarningPop();
     while (!warning.empty()) {
-      v8::Local<v8::Value> message[1] = { New(warning).ToLocalChecked() };
-      debuglog->Call(1, message, async_resource);
+      debuglog.Call({ Napi::String::New(env, warning) });
       warning = sharp::VipsWarningPop();
     }
 
-    // Return to JavaScript
-    callback->Call(2, argv, async_resource);
+    if (baton->err.empty()) {
+      Napi::Object info = Napi::Object::New(env);
+      info.Set("format", baton->format);
+      if (baton->input->bufferLength > 0) {
+        info.Set("size", baton->input->bufferLength);
+      }
+      info.Set("width", baton->width);
+      info.Set("height", baton->height);
+      info.Set("space", baton->space);
+      info.Set("channels", baton->channels);
+      info.Set("depth", baton->depth);
+      if (baton->density > 0) {
+        info.Set("density", baton->density);
+      }
+      if (!baton->chromaSubsampling.empty()) {
+        info.Set("chromaSubsampling", baton->chromaSubsampling);
+      }
+      info.Set("isProgressive", baton->isProgressive);
+      if (baton->paletteBitDepth > 0) {
+        info.Set("paletteBitDepth", baton->paletteBitDepth);
+      }
+      if (baton->pages > 0) {
+        info.Set("pages", baton->pages);
+      }
+      if (baton->pageHeight > 0) {
+        info.Set("pageHeight", baton->pageHeight);
+      }
+      if (baton->loop >= 0) {
+        info.Set("loop", baton->loop);
+      }
+      if (!baton->delay.empty()) {
+        int i = 0;
+        Napi::Array delay = Napi::Array::New(env, static_cast<size_t>(baton->delay.size()));
+        for (int const d : baton->delay) {
+          delay.Set(i++, d);
+        }
+        info.Set("delay", delay);
+      }
+      if (baton->pagePrimary > -1) {
+        info.Set("pagePrimary", baton->pagePrimary);
+      }
+      if (!baton->compression.empty()) {
+        info.Set("compression", baton->compression);
+      }
+      if (!baton->levels.empty()) {
+        int i = 0;
+        Napi::Array levels = Napi::Array::New(env, static_cast<size_t>(baton->levels.size()));
+        for (std::pair<int, int> const &l : baton->levels) {
+          Napi::Object level = Napi::Object::New(env);
+          level.Set("width", l.first);
+          level.Set("height", l.second);
+          levels.Set(i++, level);
+        }
+        info.Set("levels", levels);
+      }
+      if (baton->subifds > 0) {
+        info.Set("subifds", baton->subifds);
+      }
+      if (!baton->background.empty()) {
+        if (baton->background.size() == 3) {
+          Napi::Object background = Napi::Object::New(env);
+          background.Set("r", baton->background[0]);
+          background.Set("g", baton->background[1]);
+          background.Set("b", baton->background[2]);
+          info.Set("background", background);
+        } else {
+          info.Set("background", baton->background[0]);
+        }
+      }
+      info.Set("hasProfile", baton->hasProfile);
+      info.Set("hasAlpha", baton->hasAlpha);
+      if (baton->orientation > 0) {
+        info.Set("orientation", baton->orientation);
+      }
+      if (baton->exifLength > 0) {
+        info.Set("exif", Napi::Buffer<char>::New(env, baton->exif, baton->exifLength, sharp::FreeCallback));
+      }
+      if (baton->iccLength > 0) {
+        info.Set("icc", Napi::Buffer<char>::New(env, baton->icc, baton->iccLength, sharp::FreeCallback));
+      }
+      if (baton->iptcLength > 0) {
+        info.Set("iptc", Napi::Buffer<char>::New(env, baton->iptc, baton->iptcLength, sharp::FreeCallback));
+      }
+      if (baton->xmpLength > 0) {
+        info.Set("xmp", Napi::Buffer<char>::New(env, baton->xmp, baton->xmpLength, sharp::FreeCallback));
+      }
+      if (baton->tifftagPhotoshopLength > 0) {
+        info.Set("tifftagPhotoshop",
+          Napi::Buffer<char>::New(env, baton->tifftagPhotoshop, baton->tifftagPhotoshopLength, sharp::FreeCallback));
+      }
+      Callback().MakeCallback(Receiver().Value(), { env.Null(), info });
+    } else {
+      Callback().MakeCallback(Receiver().Value(), { Napi::Error::New(env, baton->err).Value() });
+    }
+
+    delete baton->input;
+    delete baton;
   }
 
  private:
   MetadataBaton* baton;
-  Nan::Callback *debuglog;
-  std::vector<v8::Local<v8::Object>> buffersToPersist;
+  Napi::FunctionReference debuglog;
 };
 
 /*
   metadata(options, callback)
 */
-NAN_METHOD(metadata) {
-  // Input Buffers must not undergo GC compaction during processing
-  std::vector<v8::Local<v8::Object>> buffersToPersist;
-
+Napi::Value metadata(const Napi::CallbackInfo& info) {
   // V8 objects are converted to non-V8 types held in the baton struct
   MetadataBaton *baton = new MetadataBaton;
-  v8::Local<v8::Object> options = info[0].As<v8::Object>();
+  Napi::Object options = info[0].As<Napi::Object>();
 
   // Input
-  baton->input = sharp::CreateInputDescriptor(sharp::AttrAs<v8::Object>(options, "input"), buffersToPersist);
+  baton->input = sharp::CreateInputDescriptor(options.Get("input").As<Napi::Object>());
 
   // Function to notify of libvips warnings
-  Nan::Callback *debuglog = new Nan::Callback(sharp::AttrAs<v8::Function>(options, "debuglog"));
+  Napi::Function debuglog = options.Get("debuglog").As<Napi::Function>();
 
   // Join queue for worker thread
-  Nan::Callback *callback = new Nan::Callback(info[1].As<v8::Function>());
-  Nan::AsyncQueueWorker(new MetadataWorker(callback, baton, debuglog, buffersToPersist));
+  Napi::Function callback = info[1].As<Napi::Function>();
+  MetadataWorker *worker = new MetadataWorker(callback, baton, debuglog);
+  worker->Receiver().Set("options", options);
+  worker->Queue();
 
   // Increment queued task counter
   g_atomic_int_inc(&sharp::counterQueue);
+
+  return info.Env().Undefined();
 }

src/metadata.h

@@ -1,4 +1,4 @@
-// Copyright 2013, 2014, 2015, 2016, 2017 Lovell Fuller and contributors.
+// Copyright 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Lovell Fuller and contributors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -16,7 +16,7 @@
 #define SRC_METADATA_H_
 
 #include <string>
-#include <nan.h>
+#include <napi.h>
 
 #include "./common.h"
 
@@ -31,6 +31,18 @@ struct MetadataBaton {
   int channels;
   std::string depth;
   int density;
+  std::string chromaSubsampling;
+  bool isProgressive;
+  int paletteBitDepth;
+  int pages;
+  int pageHeight;
+  int loop;
+  std::vector<int> delay;
+  int pagePrimary;
+  std::string compression;
+  std::vector<std::pair<int, int>> levels;
+  int subifds;
+  std::vector<double> background;
   bool hasProfile;
   bool hasAlpha;
   int orientation;
@@ -42,6 +54,8 @@ struct MetadataBaton {
   size_t iptcLength;
   char *xmp;
   size_t xmpLength;
+  char *tifftagPhotoshop;
+  size_t tifftagPhotoshopLength;
   std::string err;
 
   MetadataBaton():
@@ -50,6 +64,13 @@ struct MetadataBaton {
     height(0),
     channels(0),
     density(0),
+    isProgressive(false),
+    paletteBitDepth(0),
+    pages(0),
+    pageHeight(0),
+    loop(-1),
+    pagePrimary(-1),
+    subifds(0),
     hasProfile(false),
     hasAlpha(false),
     orientation(0),
@@ -60,9 +81,11 @@ struct MetadataBaton {
     iptc(nullptr),
     iptcLength(0),
     xmp(nullptr),
-    xmpLength(0) {}
+    xmpLength(0),
+    tifftagPhotoshop(nullptr),
+    tifftagPhotoshopLength(0) {}
 };
 
-NAN_METHOD(metadata);
+Napi::Value metadata(const Napi::CallbackInfo& info);
 
 #endif  // SRC_METADATA_H_

src/operations.cc

@@ -1,4 +1,4 @@
-// Copyright 2013, 2014, 2015, 2016, 2017 Lovell Fuller and contributors.
+// Copyright 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Lovell Fuller and contributors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -27,129 +27,31 @@ using vips::VImage;
 using vips::VError;
 
 namespace sharp {
-
   /*
-    Composite overlayImage over image at given position
-    Assumes alpha channels are already premultiplied and will be unpremultiplied after
+   * Tint an image using the specified chroma, preserving the original image luminance
    */
-  VImage Composite(VImage image, VImage overlayImage, int const left, int const top) {
-    if (HasAlpha(overlayImage)) {
-      // Alpha composite
-      if (overlayImage.width() < image.width() || overlayImage.height() < image.height()) {
-        // Enlarge overlay
-        std::vector<double> const background { 0.0, 0.0, 0.0, 0.0 };
-        overlayImage = overlayImage.embed(left, top, image.width(), image.height(), VImage::option()
-          ->set("extend", VIPS_EXTEND_BACKGROUND)
-          ->set("background", background));
-      }
-      return AlphaComposite(image, overlayImage);
-    } else {
-      if (HasAlpha(image)) {
-        // Add alpha channel to overlayImage so channels match
-        double const multiplier = sharp::Is16Bit(overlayImage.interpretation()) ? 256.0 : 1.0;
-        overlayImage = overlayImage.bandjoin(
-          VImage::new_matrix(overlayImage.width(), overlayImage.height()).new_from_image(255 * multiplier));
-      }
-      return image.insert(overlayImage, left, top);
+  VImage Tint(VImage image, double const a, double const b) {
+    // Get original colourspace
+    VipsInterpretation typeBeforeTint = image.interpretation();
+    if (typeBeforeTint == VIPS_INTERPRETATION_RGB) {
+      typeBeforeTint = VIPS_INTERPRETATION_sRGB;
     }
-  }
-
-  VImage AlphaComposite(VImage dst, VImage src) {
-    // Split src into non-alpha and alpha channels
-    VImage srcWithoutAlpha = src.extract_band(0, VImage::option()->set("n", src.bands() - 1));
-    VImage srcAlpha = src[src.bands() - 1] * (1.0 / 255.0);
-
-    // Split dst into non-alpha and alpha channels
-    VImage dstWithoutAlpha = dst.extract_band(0, VImage::option()->set("n", dst.bands() - 1));
-    VImage dstAlpha = dst[dst.bands() - 1] * (1.0 / 255.0);
-
-    //
-    // Compute normalized output alpha channel:
-    //
-    // References:
-    // - http://en.wikipedia.org/wiki/Alpha_compositing#Alpha_blending
-    // - https://github.com/jcupitt/ruby-vips/issues/28#issuecomment-9014826
-    //
-    // out_a = src_a + dst_a * (1 - src_a)
-    //                         ^^^^^^^^^^^
-    //                            t0
-    VImage t0 = srcAlpha.linear(-1.0, 1.0);
-    VImage outAlphaNormalized = srcAlpha + dstAlpha * t0;
-
-    //
-    // Compute output RGB channels:
-    //
-    // Wikipedia:
-    // out_rgb = (src_rgb * src_a + dst_rgb * dst_a * (1 - src_a)) / out_a
-    //                                                ^^^^^^^^^^^
-    //                                                    t0
-    //
-    // Omit division by `out_a` since `Compose` is supposed to output a
-    // premultiplied RGBA image as reversal of premultiplication is handled
-    // externally.
-    //
-    VImage outRGBPremultiplied = srcWithoutAlpha + dstWithoutAlpha * t0;
-
-    // Combine RGB and alpha channel into output image:
-    return outRGBPremultiplied.bandjoin(outAlphaNormalized * 255.0);
-  }
-
-  /*
-    Cutout src over dst with given gravity.
-   */
-  VImage Cutout(VImage mask, VImage dst, const int gravity) {
-    using sharp::CalculateCrop;
-    using sharp::HasAlpha;
-    using sharp::MaximumImageAlpha;
-
-    bool maskHasAlpha = HasAlpha(mask);
-
-    if (!maskHasAlpha && mask.bands() > 1) {
-      throw VError("Overlay image must have an alpha channel or one band");
+    // Extract luminance
+    VImage luminance = image.colourspace(VIPS_INTERPRETATION_LAB)[0];
+    // Create the tinted version by combining the L from the original and the chroma from the tint
+    std::vector<double> chroma {a, b};
+    VImage tinted = luminance
+      .bandjoin(chroma)
+      .copy(VImage::option()->set("interpretation", VIPS_INTERPRETATION_LAB))
+      .colourspace(typeBeforeTint);
+    // Attach original alpha channel, if any
+    if (HasAlpha(image)) {
+      // Extract original alpha channel
+      VImage alpha = image[image.bands() - 1];
+      // Join alpha channel to normalised image
+      tinted = tinted.bandjoin(alpha);
     }
-    if (!HasAlpha(dst)) {
-      throw VError("Image to be overlaid must have an alpha channel");
-    }
-    if (mask.width() > dst.width() || mask.height() > dst.height()) {
-      throw VError("Overlay image must have same dimensions or smaller");
-    }
-
-    // Enlarge overlay mask, if required
-    if (mask.width() < dst.width() || mask.height() < dst.height()) {
-      // Calculate the (left, top) coordinates of the output image within the input image, applying the given gravity.
-      int left;
-      int top;
-      std::tie(left, top) = CalculateCrop(dst.width(), dst.height(), mask.width(), mask.height(), gravity);
-      // Embed onto transparent background
-      std::vector<double> background { 0.0, 0.0, 0.0, 0.0 };
-      mask = mask.embed(left, top, dst.width(), dst.height(), VImage::option()
-              ->set("extend", VIPS_EXTEND_BACKGROUND)
-              ->set("background", background));
-    }
-
-    // we use the mask alpha if it has alpha
-    if (maskHasAlpha) {
-      mask = mask.extract_band(mask.bands() - 1, VImage::option()->set("n", 1));;
-    }
-
-    // Split dst into an optional alpha
-    VImage dstAlpha = dst.extract_band(dst.bands() - 1, VImage::option()->set("n", 1));
-
-    // we use the dst non-alpha
-    dst = dst.extract_band(0, VImage::option()->set("n", dst.bands() - 1));
-
-    // the range of the mask and the image need to match .. one could be
-    // 16-bit, one 8-bit
-    double const dstMax = MaximumImageAlpha(dst.interpretation());
-    double const maskMax = MaximumImageAlpha(mask.interpretation());
-
-    // combine the new mask and the existing alpha ... there are
-    // many ways of doing this, mult is the simplest
-    mask = dstMax * ((mask / maskMax) * (dstAlpha / dstMax));
-
-    // append the mask to the image data ... the mask might be float now,
-    // we must cast the format down to match the image data
-    return dst.bandjoin(mask.cast(dst.format()));
+    return tinted;
   }
 
   /*
@@ -190,21 +92,39 @@ namespace sharp {
     return image;
   }
 
+  /*
+   * Contrast limiting adapative histogram equalization (CLAHE)
+   */
+  VImage Clahe(VImage image, int const width, int const height, int const maxSlope) {
+    return image.hist_local(width, height, VImage::option()->set("max_slope", maxSlope));
+  }
+
   /*
    * Gamma encoding/decoding
    */
   VImage Gamma(VImage image, double const exponent) {
     if (HasAlpha(image)) {
       // Separate alpha channel
-      VImage imageWithoutAlpha = image.extract_band(0,
-        VImage::option()->set("n", image.bands() - 1));
       VImage alpha = image[image.bands() - 1];
-      return imageWithoutAlpha.gamma(VImage::option()->set("exponent", exponent)).bandjoin(alpha);
+      return RemoveAlpha(image).gamma(VImage::option()->set("exponent", exponent)).bandjoin(alpha);
     } else {
       return image.gamma(VImage::option()->set("exponent", exponent));
     }
   }
 
+  /**
+   * Produce the "negative" of the image.
+   */
+  VImage Negate(VImage image, bool const negateAlpha) {
+    if (HasAlpha(image) && !negateAlpha) {
+      // Separate alpha channel
+      VImage alpha = image[image.bands() - 1];
+      return RemoveAlpha(image).invert().bandjoin(alpha);
+    } else {
+      return image.invert();
+    }
+  }
+
   /*
    * Gaussian blur. Use sigma of -1.0 for fast blur.
    */
@@ -243,6 +163,49 @@ namespace sharp {
     return image.conv(kernel);
   }
 
+  /*
+   * Recomb with a Matrix of the given bands/channel size.
+   * Eg. RGB will be a 3x3 matrix.
+   */
+  VImage Recomb(VImage image, std::unique_ptr<double[]> const &matrix) {
+    double *m = matrix.get();
+    image = image.colourspace(VIPS_INTERPRETATION_sRGB);
+    return image
+      .recomb(image.bands() == 3
+        ? VImage::new_from_memory(
+          m, 9 * sizeof(double), 3, 3, 1, VIPS_FORMAT_DOUBLE
+        )
+        : VImage::new_matrixv(4, 4,
+          m[0], m[1], m[2], 0.0,
+          m[3], m[4], m[5], 0.0,
+          m[6], m[7], m[8], 0.0,
+          0.0, 0.0, 0.0, 1.0));
+  }
+
+  VImage Modulate(VImage image, double const brightness, double const saturation,
+                  int const hue, double const lightness) {
+    if (HasAlpha(image)) {
+      // Separate alpha channel
+      VImage alpha = image[image.bands() - 1];
+      return RemoveAlpha(image)
+        .colourspace(VIPS_INTERPRETATION_LCH)
+        .linear(
+          { brightness, saturation, 1},
+          { lightness, 0.0, static_cast<double>(hue) }
+        )
+        .colourspace(VIPS_INTERPRETATION_sRGB)
+        .bandjoin(alpha);
+    } else {
+      return image
+        .colourspace(VIPS_INTERPRETATION_LCH)
+        .linear(
+          { brightness, saturation, 1 },
+          { lightness, 0.0, static_cast<double>(hue) }
+        )
+        .colourspace(VIPS_INTERPRETATION_sRGB);
+    }
+  }
+
   /*
    * Sharpen flat and jagged areas. Use sigma of -1.0 for fast sharpen.
    */
@@ -289,55 +252,35 @@ namespace sharp {
     return image.boolean(imageR, boolean);
   }
 
-  VImage Trim(VImage image, int const tolerance) {
-    using sharp::MaximumImageAlpha;
-    // An equivalent of ImageMagick's -trim in C++ ... automatically remove
-    // "boring" image edges.
-
-    // We use .project to sum the rows and columns of a 0/255 mask image, the first
-    // non-zero row or column is the object edge. We make the mask image with an
-    // amount-different-from-background image plus a threshold.
-
-    // find the value of the pixel at (0, 0) ... we will search for all pixels
-    // significantly different from this
-    std::vector<double> background = image(0, 0);
-
-    double const max = MaximumImageAlpha(image.interpretation());
-
-    // we need to smooth the image, subtract the background from every pixel, take
-    // the absolute value of the difference, then threshold
-    VImage mask = (image.median(3) - background).abs() > (max * tolerance / 100);
-
-    // sum mask rows and columns, then search for the first non-zero sum in each
-    // direction
-    VImage rows;
-    VImage columns = mask.project(&rows);
-
-    VImage profileLeftV;
-    VImage profileLeftH = columns.profile(&profileLeftV);
-
-    VImage profileRightV;
-    VImage profileRightH = columns.fliphor().profile(&profileRightV);
-
-    VImage profileTopV;
-    VImage profileTopH = rows.profile(&profileTopV);
-
-    VImage profileBottomV;
-    VImage profileBottomH = rows.flipver().profile(&profileBottomV);
-
-    int left = static_cast<int>(floor(profileLeftV.min()));
-    int right = columns.width() - static_cast<int>(floor(profileRightV.min()));
-    int top = static_cast<int>(floor(profileTopH.min()));
-    int bottom = rows.height() - static_cast<int>(floor(profileBottomH.min()));
-
-    int width = right - left;
-    int height = bottom - top;
-
-    if (width <= 0 || height <= 0) {
-      throw VError("Unexpected error while trimming. Try to lower the tolerance");
+  /*
+    Trim an image
+  */
+  VImage Trim(VImage image, double const threshold) {
+    if (image.width() < 3 && image.height() < 3) {
+      throw VError("Image to trim must be at least 3x3 pixels");
+    }
+    // Top-left pixel provides the background colour
+    VImage background = image.extract_area(0, 0, 1, 1);
+    if (HasAlpha(background)) {
+      background = background.flatten();
+    }
+    int left, top, width, height;
+    left = image.find_trim(&top, &width, &height, VImage::option()
+      ->set("background", background(0, 0))
+      ->set("threshold", threshold));
+    if (width == 0 || height == 0) {
+      if (HasAlpha(image)) {
+        // Search alpha channel
+        VImage alpha = image[image.bands() - 1];
+        VImage backgroundAlpha = alpha.extract_area(0, 0, 1, 1);
+        left = alpha.find_trim(&top, &width, &height, VImage::option()
+          ->set("background", backgroundAlpha(0, 0))
+          ->set("threshold", threshold));
+      }
+      if (width == 0 || height == 0) {
+        throw VError("Unexpected error while trimming. Try to lower the tolerance");
+      }
     }
-
-    // and now crop the original image
     return image.extract_area(left, top, width, height);
   }
 
@@ -347,12 +290,22 @@ namespace sharp {
   VImage Linear(VImage image, double const a, double const b) {
     if (HasAlpha(image)) {
       // Separate alpha channel
-      VImage imageWithoutAlpha = image.extract_band(0,
-        VImage::option()->set("n", image.bands() - 1));
       VImage alpha = image[image.bands() - 1];
-      return imageWithoutAlpha.linear(a, b).bandjoin(alpha);
+      return RemoveAlpha(image).linear(a, b).bandjoin(alpha);
     } else {
       return image.linear(a, b);
     }
   }
+
+  /*
+   * Ensure the image is in a given colourspace
+   */
+  VImage EnsureColourspace(VImage image, VipsInterpretation colourspace) {
+    if (colourspace != VIPS_INTERPRETATION_LAST && image.interpretation() != colourspace) {
+      image = image.colourspace(colourspace,
+        VImage::option()->set("source_space", image.interpretation()));
+    }
+    return image;
+  }
+
 }  // namespace sharp

src/operations.h

@@ -1,4 +1,4 @@
-// Copyright 2013, 2014, 2015, 2016, 2017 Lovell Fuller and contributors.
+// Copyright 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Lovell Fuller and contributors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -26,36 +26,30 @@ using vips::VImage;
 namespace sharp {
 
   /*
-    Alpha composite src over dst with given gravity.
-    Assumes alpha channels are already premultiplied and will be unpremultiplied after.
+   * Tint an image using the specified chroma, preserving the original image luminance
    */
-  VImage Composite(VImage src, VImage dst, const int gravity);
-
-  /*
-    Composite overlayImage over image at given position
-   */
-  VImage Composite(VImage image, VImage overlayImage, int const x, int const y);
-
-  /*
-    Alpha composite overlayImage over image, assumes matching dimensions
-  */
-  VImage AlphaComposite(VImage image, VImage overlayImage);
-
-  /*
-    Cutout src over dst with given gravity.
-  */
-  VImage Cutout(VImage src, VImage dst, const int gravity);
+  VImage Tint(VImage image, double const a, double const b);
 
   /*
    * Stretch luminance to cover full dynamic range.
    */
   VImage Normalise(VImage image);
 
+  /*
+   * Contrast limiting adapative histogram equalization (CLAHE)
+   */
+  VImage Clahe(VImage image, int const width, int const height, int const maxSlope);
+
   /*
    * Gamma encoding/decoding
    */
   VImage Gamma(VImage image, double const exponent);
 
+  /*
+   * Produce the "negative" of the image.
+   */
+  VImage Negate(VImage image, bool const negateAlpha);
+
   /*
    * Gaussian blur. Use sigma of -1.0 for fast blur.
    */
@@ -90,13 +84,30 @@ namespace sharp {
   /*
     Trim an image
   */
-  VImage Trim(VImage image, int const tolerance);
+  VImage Trim(VImage image, double const threshold);
 
   /*
    * Linear adjustment (a * in + b)
    */
   VImage Linear(VImage image, double const a, double const b);
 
+  /*
+   * Recomb with a Matrix of the given bands/channel size.
+   * Eg. RGB will be a 3x3 matrix.
+   */
+  VImage Recomb(VImage image, std::unique_ptr<double[]> const &matrix);
+
+  /*
+   * Modulate brightness, saturation, hue and lightness
+   */
+  VImage Modulate(VImage image, double const brightness, double const saturation,
+                  int const hue, double const lightness);
+
+  /*
+   * Ensure the image is in a given colourspace
+   */
+  VImage EnsureColourspace(VImage image, VipsInterpretation colourspace);
+
 }  // namespace sharp
 
 #endif  // SRC_OPERATIONS_H_

src/pipeline.h

@@ -1,4 +1,4 @@
-// Copyright 2013, 2014, 2015, 2016, 2017 Lovell Fuller and contributors.
+// Copyright 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Lovell Fuller and contributors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -18,13 +18,14 @@
 #include <memory>
 #include <string>
 #include <vector>
+#include <unordered_map>
 
-#include <nan.h>
+#include <napi.h>
 #include <vips/vips8>
 
 #include "./common.h"
 
-NAN_METHOD(pipeline);
+Napi::Value pipeline(const Napi::CallbackInfo& info);
 
 enum class Canvas {
   CROP,
@@ -34,20 +35,34 @@ enum class Canvas {
   IGNORE_ASPECT
 };
 
+struct Composite {
+  sharp::InputDescriptor *input;
+  VipsBlendMode mode;
+  int gravity;
+  int left;
+  int top;
+  bool hasOffset;
+  bool tile;
+  bool premultiplied;
+
+  Composite():
+    input(nullptr),
+    mode(VIPS_BLEND_MODE_OVER),
+    gravity(0),
+    left(0),
+    top(0),
+    hasOffset(false),
+    tile(false),
+    premultiplied(false) {}
+};
+
 struct PipelineBaton {
   sharp::InputDescriptor *input;
-  std::string iccProfilePath;
-  int limitInputPixels;
   std::string formatOut;
   std::string fileOut;
   void *bufferOut;
   size_t bufferOutLength;
-  sharp::InputDescriptor *overlay;
-  int overlayGravity;
-  int overlayXOffset;
-  int overlayYOffset;
-  bool overlayTile;
-  bool overlayCutout;
+  std::vector<Composite *> composite;
   std::vector<sharp::InputDescriptor *> joinChannelIn;
   int topOffsetPre;
   int leftOffsetPre;
@@ -61,31 +76,48 @@ struct PipelineBaton {
   int height;
   int channels;
   Canvas canvas;
-  int crop;
-  int embed;
+  int position;
+  std::vector<double> resizeBackground;
   bool hasCropOffset;
   int cropOffsetLeft;
   int cropOffsetTop;
   bool premultiplied;
+  bool tileCentre;
   std::string kernel;
   bool fastShrinkOnLoad;
-  double background[4];
+  double tintA;
+  double tintB;
   bool flatten;
+  std::vector<double> flattenBackground;
   bool negate;
+  bool negateAlpha;
   double blurSigma;
+  double brightness;
+  double saturation;
+  int hue;
+  double lightness;
+  int medianSize;
   double sharpenSigma;
   double sharpenFlat;
   double sharpenJagged;
   int threshold;
   bool thresholdGrayscale;
-  int trimTolerance;
+  double trimThreshold;
+  int trimOffsetLeft;
+  int trimOffsetTop;
   double linearA;
   double linearB;
   double gamma;
+  double gammaOut;
   bool greyscale;
   bool normalise;
+  int claheWidth;
+  int claheHeight;
+  int claheMaxSlope;
   bool useExifOrientation;
   int angle;
+  double rotationAngle;
+  std::vector<double> rotationBackground;
   bool rotateBeforePreExtract;
   bool flip;
   bool flop;
@@ -93,30 +125,64 @@ struct PipelineBaton {
   int extendBottom;
   int extendLeft;
   int extendRight;
+  std::vector<double> extendBackground;
   bool withoutEnlargement;
-  VipsAccess accessMethod;
+  std::vector<double> affineMatrix;
+  std::vector<double> affineBackground;
+  double affineIdx;
+  double affineIdy;
+  double affineOdx;
+  double affineOdy;
+  vips::VInterpolate affineInterpolator;
   int jpegQuality;
   bool jpegProgressive;
   std::string jpegChromaSubsampling;
   bool jpegTrellisQuantisation;
+  int jpegQuantisationTable;
   bool jpegOvershootDeringing;
   bool jpegOptimiseScans;
+  bool jpegOptimiseCoding;
   bool pngProgressive;
   int pngCompressionLevel;
   bool pngAdaptiveFiltering;
+  bool pngPalette;
+  int pngQuality;
+  int pngBitdepth;
+  double pngDither;
+  int jp2Quality;
+  bool jp2Lossless;
+  int jp2TileHeight;
+  int jp2TileWidth;
+  std::string jp2ChromaSubsampling;
   int webpQuality;
   int webpAlphaQuality;
   bool webpNearLossless;
   bool webpLossless;
+  bool webpSmartSubsample;
+  int webpReductionEffort;
   int tiffQuality;
   VipsForeignTiffCompression tiffCompression;
   VipsForeignTiffPredictor tiffPredictor;
-  bool tiffSquash;
+  bool tiffPyramid;
+  int tiffBitdepth;
+  bool tiffTile;
+  int tiffTileHeight;
+  int tiffTileWidth;
   double tiffXres;
   double tiffYres;
+  int heifQuality;
+  VipsForeignHeifCompression heifCompression;
+  int heifSpeed;
+  std::string heifChromaSubsampling;
+  bool heifLossless;
+  VipsBandFormat rawDepth;
   std::string err;
   bool withMetadata;
   int withMetadataOrientation;
+  double withMetadataDensity;
+  std::string withMetadataIcc;
+  std::unordered_map<std::string, std::string> withMetadataStrs;
+  int timeoutSeconds;
   std::unique_ptr<double[]> convKernel;
   int convKernelWidth;
   int convKernelHeight;
@@ -126,75 +192,131 @@ struct PipelineBaton {
   VipsOperationBoolean booleanOp;
   VipsOperationBoolean bandBoolOp;
   int extractChannel;
+  bool removeAlpha;
+  double ensureAlpha;
+  VipsInterpretation colourspaceInput;
   VipsInterpretation colourspace;
+  int pageHeight;
+  std::vector<int> delay;
+  int loop;
   int tileSize;
   int tileOverlap;
   VipsForeignDzContainer tileContainer;
   VipsForeignDzLayout tileLayout;
   std::string tileFormat;
   int tileAngle;
+  std::vector<double> tileBackground;
+  int tileSkipBlanks;
+  VipsForeignDzDepth tileDepth;
+  std::string tileId;
+  std::unique_ptr<double[]> recombMatrix;
 
   PipelineBaton():
     input(nullptr),
-    limitInputPixels(0),
     bufferOutLength(0),
-    overlay(nullptr),
-    overlayGravity(0),
-    overlayXOffset(-1),
-    overlayYOffset(-1),
-    overlayTile(false),
-    overlayCutout(false),
     topOffsetPre(-1),
     topOffsetPost(-1),
     channels(0),
     canvas(Canvas::CROP),
-    crop(0),
-    embed(0),
+    position(0),
+    resizeBackground{ 0.0, 0.0, 0.0, 255.0 },
     hasCropOffset(false),
     cropOffsetLeft(0),
     cropOffsetTop(0),
     premultiplied(false),
+    tintA(128.0),
+    tintB(128.0),
     flatten(false),
+    flattenBackground{ 0.0, 0.0, 0.0 },
     negate(false),
+    negateAlpha(true),
     blurSigma(0.0),
+    brightness(1.0),
+    saturation(1.0),
+    hue(0),
+    lightness(0),
+    medianSize(0),
     sharpenSigma(0.0),
     sharpenFlat(1.0),
     sharpenJagged(2.0),
     threshold(0),
     thresholdGrayscale(true),
-    trimTolerance(0),
+    trimThreshold(0.0),
+    trimOffsetLeft(0),
+    trimOffsetTop(0),
     linearA(1.0),
     linearB(0.0),
     gamma(0.0),
     greyscale(false),
     normalise(false),
+    claheWidth(0),
+    claheHeight(0),
+    claheMaxSlope(3),
     useExifOrientation(false),
     angle(0),
+    rotationAngle(0.0),
+    rotationBackground{ 0.0, 0.0, 0.0, 255.0 },
     flip(false),
     flop(false),
     extendTop(0),
     extendBottom(0),
     extendLeft(0),
     extendRight(0),
+    extendBackground{ 0.0, 0.0, 0.0, 255.0 },
     withoutEnlargement(false),
+    affineMatrix{ 1.0, 0.0, 0.0, 1.0 },
+    affineBackground{ 0.0, 0.0, 0.0, 255.0 },
+    affineIdx(0),
+    affineIdy(0),
+    affineOdx(0),
+    affineOdy(0),
+    affineInterpolator(vips::VInterpolate::new_from_name("bicubic")),
     jpegQuality(80),
     jpegProgressive(false),
     jpegChromaSubsampling("4:2:0"),
     jpegTrellisQuantisation(false),
+    jpegQuantisationTable(0),
     jpegOvershootDeringing(false),
     jpegOptimiseScans(false),
+    jpegOptimiseCoding(true),
     pngProgressive(false),
-    pngCompressionLevel(9),
+    pngCompressionLevel(6),
     pngAdaptiveFiltering(false),
+    pngPalette(false),
+    pngQuality(100),
+    pngBitdepth(8),
+    pngDither(1.0),
+    jp2Quality(80),
+    jp2Lossless(false),
+    jp2TileHeight(512),
+    jp2TileWidth(512),
+    jp2ChromaSubsampling("4:4:4"),
     webpQuality(80),
+    webpAlphaQuality(100),
+    webpNearLossless(false),
+    webpLossless(false),
+    webpSmartSubsample(false),
+    webpReductionEffort(4),
     tiffQuality(80),
     tiffCompression(VIPS_FOREIGN_TIFF_COMPRESSION_JPEG),
     tiffPredictor(VIPS_FOREIGN_TIFF_PREDICTOR_HORIZONTAL),
-    tiffSquash(false),
+    tiffPyramid(false),
+    tiffBitdepth(8),
+    tiffTile(false),
+    tiffTileHeight(256),
+    tiffTileWidth(256),
     tiffXres(1.0),
     tiffYres(1.0),
+    heifQuality(50),
+    heifCompression(VIPS_FOREIGN_HEIF_COMPRESSION_AV1),
+    heifSpeed(5),
+    heifChromaSubsampling("4:4:4"),
+    heifLossless(false),
+    rawDepth(VIPS_FORMAT_UCHAR),
     withMetadata(false),
     withMetadataOrientation(-1),
+    withMetadataDensity(0.0),
+    timeoutSeconds(0),
     convKernelWidth(0),
     convKernelHeight(0),
     convKernelScale(0.0),
@@ -203,17 +325,21 @@ struct PipelineBaton {
     booleanOp(VIPS_OPERATION_BOOLEAN_LAST),
     bandBoolOp(VIPS_OPERATION_BOOLEAN_LAST),
     extractChannel(-1),
+    removeAlpha(false),
+    ensureAlpha(-1.0),
+    colourspaceInput(VIPS_INTERPRETATION_LAST),
     colourspace(VIPS_INTERPRETATION_LAST),
+    pageHeight(0),
+    delay{-1},
+    loop(-1),
     tileSize(256),
     tileOverlap(0),
     tileContainer(VIPS_FOREIGN_DZ_CONTAINER_FS),
     tileLayout(VIPS_FOREIGN_DZ_LAYOUT_DZ),
-    tileAngle(0){
-      background[0] = 0.0;
-      background[1] = 0.0;
-      background[2] = 0.0;
-      background[3] = 255.0;
-    }
+    tileAngle(0),
+    tileBackground{ 255.0, 255.0, 255.0, 255.0 },
+    tileSkipBlanks(-1),
+    tileDepth(VIPS_FOREIGN_DZ_DEPTH_LAST) {}
 };
 
 #endif  // SRC_PIPELINE_H_

src/sharp.cc

@@ -1,4 +1,4 @@
-// Copyright 2013, 2014, 2015, 2016, 2017 Lovell Fuller and contributors.
+// Copyright 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Lovell Fuller and contributors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -12,8 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include <node.h>
-#include <nan.h>
+#include <napi.h>
 #include <vips/vips8>
 
 #include "common.h"
@@ -22,33 +21,32 @@
 #include "utilities.h"
 #include "stats.h"
 
-NAN_MODULE_INIT(init) {
+static void* sharp_vips_init(void*) {
+  g_setenv("VIPS_MIN_STACK_SIZE", "2m", FALSE);
   vips_init("sharp");
+  return nullptr;
+}
+
+Napi::Object init(Napi::Env env, Napi::Object exports) {
+  static GOnce sharp_vips_init_once = G_ONCE_INIT;
+  g_once(&sharp_vips_init_once, static_cast<GThreadFunc>(sharp_vips_init), nullptr);
 
   g_log_set_handler("VIPS", static_cast<GLogLevelFlags>(G_LOG_LEVEL_WARNING),
     static_cast<GLogFunc>(sharp::VipsWarningCallback), nullptr);
 
   // Methods available to JavaScript
-  Nan::Set(target, Nan::New("metadata").ToLocalChecked(),
-    Nan::GetFunction(Nan::New<v8::FunctionTemplate>(metadata)).ToLocalChecked());
-  Nan::Set(target, Nan::New("pipeline").ToLocalChecked(),
-    Nan::GetFunction(Nan::New<v8::FunctionTemplate>(pipeline)).ToLocalChecked());
-  Nan::Set(target, Nan::New("cache").ToLocalChecked(),
-    Nan::GetFunction(Nan::New<v8::FunctionTemplate>(cache)).ToLocalChecked());
-  Nan::Set(target, Nan::New("concurrency").ToLocalChecked(),
-    Nan::GetFunction(Nan::New<v8::FunctionTemplate>(concurrency)).ToLocalChecked());
-  Nan::Set(target, Nan::New("counters").ToLocalChecked(),
-    Nan::GetFunction(Nan::New<v8::FunctionTemplate>(counters)).ToLocalChecked());
-  Nan::Set(target, Nan::New("simd").ToLocalChecked(),
-    Nan::GetFunction(Nan::New<v8::FunctionTemplate>(simd)).ToLocalChecked());
-  Nan::Set(target, Nan::New("libvipsVersion").ToLocalChecked(),
-    Nan::GetFunction(Nan::New<v8::FunctionTemplate>(libvipsVersion)).ToLocalChecked());
-  Nan::Set(target, Nan::New("format").ToLocalChecked(),
-    Nan::GetFunction(Nan::New<v8::FunctionTemplate>(format)).ToLocalChecked());
-  Nan::Set(target, Nan::New("_maxColourDistance").ToLocalChecked(),
-    Nan::GetFunction(Nan::New<v8::FunctionTemplate>(_maxColourDistance)).ToLocalChecked());
-  Nan::Set(target, Nan::New("stats").ToLocalChecked(),
-    Nan::GetFunction(Nan::New<v8::FunctionTemplate>(stats)).ToLocalChecked());
+  exports.Set("metadata", Napi::Function::New(env, metadata));
+  exports.Set("pipeline", Napi::Function::New(env, pipeline));
+  exports.Set("cache", Napi::Function::New(env, cache));
+  exports.Set("concurrency", Napi::Function::New(env, concurrency));
+  exports.Set("counters", Napi::Function::New(env, counters));
+  exports.Set("simd", Napi::Function::New(env, simd));
+  exports.Set("libvipsVersion", Napi::Function::New(env, libvipsVersion));
+  exports.Set("format", Napi::Function::New(env, format));
+  exports.Set("_maxColourDistance", Napi::Function::New(env, _maxColourDistance));
+  exports.Set("_isUsingJemalloc", Napi::Function::New(env, _isUsingJemalloc));
+  exports.Set("stats", Napi::Function::New(env, stats));
+  return exports;
 }
 
-NODE_MODULE(sharp, init)
+NODE_API_MODULE(sharp, init)

src/stats.cc

@@ -1,4 +1,4 @@
-// Copyright 2013, 2014, 2015, 2016, 2017 Lovell Fuller and contributors.
+// Copyright 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Lovell Fuller and contributors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -16,28 +16,16 @@
 #include <vector>
 #include <iostream>
 
-#include <node.h>
-#include <nan.h>
+#include <napi.h>
 #include <vips/vips8>
 
 #include "common.h"
 #include "stats.h"
 
-class StatsWorker : public Nan::AsyncWorker {
+class StatsWorker : public Napi::AsyncWorker {
  public:
-  StatsWorker(
-    Nan::Callback *callback, StatsBaton *baton, Nan::Callback *debuglog,
-    std::vector<v8::Local<v8::Object>> const buffersToPersist) :
-    Nan::AsyncWorker(callback, "sharp:StatsWorker"),
-    baton(baton), debuglog(debuglog),
-    buffersToPersist(buffersToPersist) {
-    // Protect Buffer objects from GC, keyed on index
-    std::accumulate(buffersToPersist.begin(), buffersToPersist.end(), 0,
-      [this](uint32_t index, v8::Local<v8::Object> const buffer) -> uint32_t {
-        SaveToPersistent(index, buffer);
-        return index + 1;
-      });
-  }
+  StatsWorker(Napi::Function callback, StatsBaton *baton, Napi::Function debuglog) :
+    Napi::AsyncWorker(callback), baton(baton), debuglog(Napi::Persistent(debuglog)) {}
   ~StatsWorker() {}
 
   const int STAT_MIN_INDEX = 0;
@@ -54,40 +42,64 @@ class StatsWorker : public Nan::AsyncWorker {
   void Execute() {
     // Decrement queued task counter
     g_atomic_int_dec_and_test(&sharp::counterQueue);
-    using Nan::New;
-    using Nan::Set;
-    using sharp::MaximumImageAlpha;
 
     vips::VImage image;
-    vips::VImage stats;
     sharp::ImageType imageType = sharp::ImageType::UNKNOWN;
-
     try {
-      std::tie(image, imageType) = OpenInput(baton->input, baton->accessMethod);
+      std::tie(image, imageType) = OpenInput(baton->input);
     } catch (vips::VError const &err) {
       (baton->err).append(err.what());
     }
     if (imageType != sharp::ImageType::UNKNOWN) {
       try {
-        stats = image.stats();
-        int bands = image.bands();
-        double const max = MaximumImageAlpha(image.interpretation());
+        vips::VImage stats = image.stats();
+        int const bands = image.bands();
         for (int b = 1; b <= bands; b++) {
-          ChannelStats cStats(static_cast<int>(stats.getpoint(STAT_MIN_INDEX, b).front()),
-                              static_cast<int>(stats.getpoint(STAT_MAX_INDEX, b).front()),
-                              stats.getpoint(STAT_SUM_INDEX, b).front(), stats.getpoint(STAT_SQ_SUM_INDEX, b).front(),
-                              stats.getpoint(STAT_MEAN_INDEX, b).front(), stats.getpoint(STAT_STDEV_INDEX, b).front(),
-                              static_cast<int>(stats.getpoint(STAT_MINX_INDEX, b).front()),
-                              static_cast<int>(stats.getpoint(STAT_MINY_INDEX, b).front()),
-                              static_cast<int>(stats.getpoint(STAT_MAXX_INDEX, b).front()),
-                              static_cast<int>(stats.getpoint(STAT_MAXY_INDEX, b).front()));
+          ChannelStats cStats(
+            static_cast<int>(stats.getpoint(STAT_MIN_INDEX, b).front()),
+            static_cast<int>(stats.getpoint(STAT_MAX_INDEX, b).front()),
+            stats.getpoint(STAT_SUM_INDEX, b).front(),
+            stats.getpoint(STAT_SQ_SUM_INDEX, b).front(),
+            stats.getpoint(STAT_MEAN_INDEX, b).front(),
+            stats.getpoint(STAT_STDEV_INDEX, b).front(),
+            static_cast<int>(stats.getpoint(STAT_MINX_INDEX, b).front()),
+            static_cast<int>(stats.getpoint(STAT_MINY_INDEX, b).front()),
+            static_cast<int>(stats.getpoint(STAT_MAXX_INDEX, b).front()),
+            static_cast<int>(stats.getpoint(STAT_MAXY_INDEX, b).front()));
           baton->channelStats.push_back(cStats);
         }
-
-        // alpha layer is there and the last band i.e. alpha has its max value greater than 0)
-        if (sharp::HasAlpha(image) && stats.getpoint(STAT_MIN_INDEX, bands).front() != max) {
-          baton->isOpaque = false;
+        // Image is not opaque when alpha layer is present and contains a non-mamixa value
+        if (sharp::HasAlpha(image)) {
+          double const minAlpha = static_cast<double>(stats.getpoint(STAT_MIN_INDEX, bands).front());
+          if (minAlpha != sharp::MaximumImageAlpha(image.interpretation())) {
+            baton->isOpaque = false;
+          }
         }
+        // Convert to greyscale
+        vips::VImage greyscale = image.colourspace(VIPS_INTERPRETATION_B_W)[0];
+        // Estimate entropy via histogram of greyscale value frequency
+        baton->entropy = std::abs(greyscale.hist_find().hist_entropy());
+        // Estimate sharpness via standard deviation of greyscale laplacian
+        if (image.width() > 1 || image.height() > 1) {
+          VImage laplacian = VImage::new_matrixv(3, 3,
+            0.0,  1.0, 0.0,
+            1.0, -4.0, 1.0,
+            0.0,  1.0, 0.0);
+          laplacian.set("scale", 9.0);
+          baton->sharpness = greyscale.conv(laplacian).deviate();
+        }
+        // Most dominant sRGB colour via 4096-bin 3D histogram
+        vips::VImage hist = sharp::RemoveAlpha(image)
+          .colourspace(VIPS_INTERPRETATION_sRGB)
+          .hist_find_ndim(VImage::option()->set("bins", 16));
+        std::complex<double> maxpos = hist.maxpos();
+        int const dx = static_cast<int>(std::real(maxpos));
+        int const dy = static_cast<int>(std::imag(maxpos));
+        std::vector<double> pel = hist(dx, dy);
+        int const dz = std::distance(pel.begin(), std::find(pel.begin(), pel.end(), hist.max()));
+        baton->dominantRed = dx * 16 + 8;
+        baton->dominantGreen = dy * 16 + 8;
+        baton->dominantBlue = dz * 16 + 8;
       } catch (vips::VError const &err) {
         (baton->err).append(err.what());
       }
@@ -98,92 +110,84 @@ class StatsWorker : public Nan::AsyncWorker {
     vips_thread_shutdown();
   }
 
-  void HandleOKCallback() {
-    using Nan::New;
-    using Nan::Set;
-    Nan::HandleScope();
-
-    v8::Local<v8::Value> argv[2] = { Nan::Null(), Nan::Null() };
-    if (!baton->err.empty()) {
-      argv[0] = Nan::Error(baton->err.data());
-    } else {
-      // Stats Object
-      v8::Local<v8::Object> info = New<v8::Object>();
-      v8::Local<v8::Array> channels = New<v8::Array>();
-
-      std::vector<ChannelStats>::iterator it;
-      int i = 0;
-      for (it=baton->channelStats.begin() ; it < baton->channelStats.end(); it++, i++) {
-        v8::Local<v8::Object> channelStat = New<v8::Object>();
-        Set(channelStat, New("min").ToLocalChecked(), New<v8::Number>(it->min));
-        Set(channelStat, New("max").ToLocalChecked(), New<v8::Number>(it->max));
-        Set(channelStat, New("sum").ToLocalChecked(), New<v8::Number>(it->sum));
-        Set(channelStat, New("squaresSum").ToLocalChecked(), New<v8::Number>(it->squaresSum));
-        Set(channelStat, New("mean").ToLocalChecked(), New<v8::Number>(it->mean));
-        Set(channelStat, New("stdev").ToLocalChecked(), New<v8::Number>(it->stdev));
-        Set(channelStat, New("minX").ToLocalChecked(), New<v8::Number>(it->minX));
-        Set(channelStat, New("minY").ToLocalChecked(), New<v8::Number>(it->minY));
-        Set(channelStat, New("maxX").ToLocalChecked(), New<v8::Number>(it->maxX));
-        Set(channelStat, New("maxY").ToLocalChecked(), New<v8::Number>(it->maxY));
-        channels->Set(i, channelStat);
-      }
-
-      Set(info, New("channels").ToLocalChecked(), channels);
-      Set(info, New("isOpaque").ToLocalChecked(), New<v8::Boolean>(baton->isOpaque));
-      argv[1] = info;
-    }
-
-    // Dispose of Persistent wrapper around input Buffers so they can be garbage collected
-    std::accumulate(buffersToPersist.begin(), buffersToPersist.end(), 0,
-      [this](uint32_t index, v8::Local<v8::Object> const buffer) -> uint32_t {
-        GetFromPersistent(index);
-        return index + 1;
-      });
-    delete baton->input;
-    delete baton;
+  void OnOK() {
+    Napi::Env env = Env();
+    Napi::HandleScope scope(env);
 
     // Handle warnings
     std::string warning = sharp::VipsWarningPop();
     while (!warning.empty()) {
-      v8::Local<v8::Value> message[1] = { New(warning).ToLocalChecked() };
-      debuglog->Call(1, message, async_resource);
+      debuglog.Call({ Napi::String::New(env, warning) });
       warning = sharp::VipsWarningPop();
     }
 
-    // Return to JavaScript
-    callback->Call(2, argv, async_resource);
+    if (baton->err.empty()) {
+      // Stats Object
+      Napi::Object info = Napi::Object::New(env);
+      Napi::Array channels = Napi::Array::New(env);
+
+      std::vector<ChannelStats>::iterator it;
+      int i = 0;
+      for (it = baton->channelStats.begin(); it < baton->channelStats.end(); it++, i++) {
+        Napi::Object channelStat = Napi::Object::New(env);
+        channelStat.Set("min", it->min);
+        channelStat.Set("max", it->max);
+        channelStat.Set("sum", it->sum);
+        channelStat.Set("squaresSum", it->squaresSum);
+        channelStat.Set("mean", it->mean);
+        channelStat.Set("stdev", it->stdev);
+        channelStat.Set("minX", it->minX);
+        channelStat.Set("minY", it->minY);
+        channelStat.Set("maxX", it->maxX);
+        channelStat.Set("maxY", it->maxY);
+        channels.Set(i, channelStat);
+      }
+
+      info.Set("channels", channels);
+      info.Set("isOpaque", baton->isOpaque);
+      info.Set("entropy", baton->entropy);
+      info.Set("sharpness", baton->sharpness);
+      Napi::Object dominant = Napi::Object::New(env);
+      dominant.Set("r", baton->dominantRed);
+      dominant.Set("g", baton->dominantGreen);
+      dominant.Set("b", baton->dominantBlue);
+      info.Set("dominant", dominant);
+      Callback().MakeCallback(Receiver().Value(), { env.Null(), info });
+    } else {
+      Callback().MakeCallback(Receiver().Value(), { Napi::Error::New(env, baton->err).Value() });
+    }
+
+    delete baton->input;
+    delete baton;
   }
 
  private:
   StatsBaton* baton;
-  Nan::Callback *debuglog;
-  std::vector<v8::Local<v8::Object>> buffersToPersist;
+  Napi::FunctionReference debuglog;
 };
 
 /*
   stats(options, callback)
 */
-NAN_METHOD(stats) {
-  using sharp::AttrTo;
-
-  // Input Buffers must not undergo GC compaction during processing
-  std::vector<v8::Local<v8::Object>> buffersToPersist;
-
+Napi::Value stats(const Napi::CallbackInfo& info) {
   // V8 objects are converted to non-V8 types held in the baton struct
   StatsBaton *baton = new StatsBaton;
-  v8::Local<v8::Object> options = info[0].As<v8::Object>();
+  Napi::Object options = info[0].As<Napi::Object>();
 
   // Input
-  baton->input = sharp::CreateInputDescriptor(sharp::AttrAs<v8::Object>(options, "input"), buffersToPersist);
-  baton->accessMethod = AttrTo<bool>(options, "sequentialRead") ? VIPS_ACCESS_SEQUENTIAL : VIPS_ACCESS_RANDOM;
+  baton->input = sharp::CreateInputDescriptor(options.Get("input").As<Napi::Object>());
 
   // Function to notify of libvips warnings
-  Nan::Callback *debuglog = new Nan::Callback(sharp::AttrAs<v8::Function>(options, "debuglog"));
+  Napi::Function debuglog = options.Get("debuglog").As<Napi::Function>();
 
   // Join queue for worker thread
-  Nan::Callback *callback = new Nan::Callback(info[1].As<v8::Function>());
-  Nan::AsyncQueueWorker(new StatsWorker(callback, baton, debuglog, buffersToPersist));
+  Napi::Function callback = info[1].As<Napi::Function>();
+  StatsWorker *worker = new StatsWorker(callback, baton, debuglog);
+  worker->Receiver().Set("options", options);
+  worker->Queue();
 
   // Increment queued task counter
   g_atomic_int_inc(&sharp::counterQueue);
+
+  return info.Env().Undefined();
 }

src/stats.h

@@ -1,4 +1,4 @@
-// Copyright 2013, 2014, 2015, 2016, 2017 Lovell Fuller and contributors.
+// Copyright 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Lovell Fuller and contributors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -16,7 +16,7 @@
 #define SRC_STATS_H_
 
 #include <string>
-#include <nan.h>
+#include <napi.h>
 
 #include "./common.h"
 
@@ -33,12 +33,8 @@ struct ChannelStats {
   int maxX;
   int maxY;
 
-  ChannelStats():
-    min(0), max(0), sum(0), squaresSum(0), mean(0), stdev(0)
-    , minX(0), minY(0), maxX(0), maxY(0) {}
-
-    ChannelStats(int minVal, int maxVal, double sumVal, double squaresSumVal,
-                  double meanVal, double stdevVal, int minXVal, int minYVal, int maxXVal, int maxYVal):
+  ChannelStats(int minVal, int maxVal, double sumVal, double squaresSumVal,
+    double meanVal, double stdevVal, int minXVal, int minYVal, int maxXVal, int maxYVal):
     min(minVal), max(maxVal), sum(sumVal), squaresSum(squaresSumVal),
     mean(meanVal), stdev(stdevVal), minX(minXVal), minY(minYVal), maxX(maxXVal), maxY(maxYVal) {}
 };
@@ -46,20 +42,29 @@ struct ChannelStats {
 struct StatsBaton {
   // Input
   sharp::InputDescriptor *input;
-  VipsAccess accessMethod;
 
   // Output
   std::vector<ChannelStats> channelStats;
   bool isOpaque;
+  double entropy;
+  double sharpness;
+  int dominantRed;
+  int dominantGreen;
+  int dominantBlue;
 
   std::string err;
 
   StatsBaton():
     input(nullptr),
-    isOpaque(true)
+    isOpaque(true),
+    entropy(0.0),
+    sharpness(0.0),
+    dominantRed(0),
+    dominantGreen(0),
+    dominantBlue(0)
     {}
 };
 
-NAN_METHOD(stats);
+Napi::Value stats(const Napi::CallbackInfo& info);
 
 #endif  // SRC_STATS_H_

src/utilities.cc

@@ -1,4 +1,4 @@
-// Copyright 2013, 2014, 2015, 2016, 2017 Lovell Fuller and contributors.
+// Copyright 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Lovell Fuller and contributors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -15,8 +15,7 @@
 #include <cmath>
 #include <string>
 
-#include <node.h>
-#include <nan.h>
+#include <napi.h>
 #include <vips/vips8>
 #include <vips/vector.h>
 
@@ -24,182 +23,145 @@
 #include "operations.h"
 #include "utilities.h"
 
-using v8::Boolean;
-using v8::Integer;
-using v8::Local;
-using v8::Number;
-using v8::Object;
-using v8::String;
-
-using Nan::HandleScope;
-using Nan::New;
-using Nan::Set;
-using Nan::ThrowError;
-using Nan::To;
-using Nan::Utf8String;
-
 /*
   Get and set cache limits
 */
-NAN_METHOD(cache) {
-  HandleScope();
+Napi::Value cache(const Napi::CallbackInfo& info) {
+  Napi::Env env = info.Env();
 
   // Set memory limit
-  if (info[0]->IsInt32()) {
-    vips_cache_set_max_mem(To<int32_t>(info[0]).FromJust() * 1048576);
+  if (info[0].IsNumber()) {
+    vips_cache_set_max_mem(info[0].As<Napi::Number>().Int32Value() * 1048576);
   }
   // Set file limit
-  if (info[1]->IsInt32()) {
-    vips_cache_set_max_files(To<int32_t>(info[1]).FromJust());
+  if (info[1].IsNumber()) {
+    vips_cache_set_max_files(info[1].As<Napi::Number>().Int32Value());
   }
   // Set items limit
-  if (info[2]->IsInt32()) {
-    vips_cache_set_max(To<int32_t>(info[2]).FromJust());
+  if (info[2].IsNumber()) {
+    vips_cache_set_max(info[2].As<Napi::Number>().Int32Value());
   }
 
   // Get memory stats
-  Local<Object> memory = New<Object>();
-  Set(memory, New("current").ToLocalChecked(),
-    New<Integer>(static_cast<int>(round(vips_tracked_get_mem() / 1048576))));
-  Set(memory, New("high").ToLocalChecked(),
-    New<Integer>(static_cast<int>(round(vips_tracked_get_mem_highwater() / 1048576))));
-  Set(memory, New("max").ToLocalChecked(),
-    New<Integer>(static_cast<int>(round(vips_cache_get_max_mem() / 1048576))));
+  Napi::Object memory = Napi::Object::New(env);
+  memory.Set("current", round(vips_tracked_get_mem() / 1048576));
+  memory.Set("high", round(vips_tracked_get_mem_highwater() / 1048576));
+  memory.Set("max", round(vips_cache_get_max_mem() / 1048576));
   // Get file stats
-  Local<Object> files = New<Object>();
-  Set(files, New("current").ToLocalChecked(), New<Integer>(vips_tracked_get_files()));
-  Set(files, New("max").ToLocalChecked(), New<Integer>(vips_cache_get_max_files()));
+  Napi::Object files = Napi::Object::New(env);
+  files.Set("current", vips_tracked_get_files());
+  files.Set("max", vips_cache_get_max_files());
 
   // Get item stats
-  Local<Object> items = New<Object>();
-  Set(items, New("current").ToLocalChecked(), New<Integer>(vips_cache_get_size()));
-  Set(items, New("max").ToLocalChecked(), New<Integer>(vips_cache_get_max()));
+  Napi::Object items = Napi::Object::New(env);
+  items.Set("current", vips_cache_get_size());
+  items.Set("max", vips_cache_get_max());
 
-  Local<Object> cache = New<Object>();
-  Set(cache, New("memory").ToLocalChecked(), memory);
-  Set(cache, New("files").ToLocalChecked(), files);
-  Set(cache, New("items").ToLocalChecked(), items);
-  info.GetReturnValue().Set(cache);
+  Napi::Object cache = Napi::Object::New(env);
+  cache.Set("memory", memory);
+  cache.Set("files", files);
+  cache.Set("items", items);
+  return cache;
 }
 
 /*
   Get and set size of thread pool
 */
-NAN_METHOD(concurrency) {
-  HandleScope();
-
+Napi::Value concurrency(const Napi::CallbackInfo& info) {
   // Set concurrency
-  if (info[0]->IsInt32()) {
-    vips_concurrency_set(To<int32_t>(info[0]).FromJust());
+  if (info[0].IsNumber()) {
+    vips_concurrency_set(info[0].As<Napi::Number>().Int32Value());
   }
   // Get concurrency
-  info.GetReturnValue().Set(New<Integer>(vips_concurrency_get()));
+  return Napi::Number::New(info.Env(), vips_concurrency_get());
 }
 
 /*
   Get internal counters (queued tasks, processing tasks)
 */
-NAN_METHOD(counters) {
-  using sharp::counterProcess;
-  using sharp::counterQueue;
-
-  HandleScope();
-  Local<Object> counters = New<Object>();
-  Set(counters, New("queue").ToLocalChecked(), New<Integer>(counterQueue));
-  Set(counters, New("process").ToLocalChecked(), New<Integer>(counterProcess));
-  info.GetReturnValue().Set(counters);
+Napi::Value counters(const Napi::CallbackInfo& info) {
+  Napi::Object counters = Napi::Object::New(info.Env());
+  counters.Set("queue", sharp::counterQueue);
+  counters.Set("process", sharp::counterProcess);
+  return counters;
 }
 
 /*
   Get and set use of SIMD vector unit instructions
 */
-NAN_METHOD(simd) {
-  HandleScope();
-
+Napi::Value simd(const Napi::CallbackInfo& info) {
   // Set state
-  if (info[0]->IsBoolean()) {
-    vips_vector_set_enabled(To<bool>(info[0]).FromJust());
+  if (info[0].IsBoolean()) {
+    vips_vector_set_enabled(info[0].As<Napi::Boolean>().Value());
   }
   // Get state
-  info.GetReturnValue().Set(New<Boolean>(vips_vector_isenabled()));
+  return Napi::Boolean::New(info.Env(), vips_vector_isenabled());
 }
 
 /*
   Get libvips version
 */
-NAN_METHOD(libvipsVersion) {
-  HandleScope();
+Napi::Value libvipsVersion(const Napi::CallbackInfo& info) {
   char version[9];
   g_snprintf(version, sizeof(version), "%d.%d.%d", vips_version(0), vips_version(1), vips_version(2));
-  info.GetReturnValue().Set(New(version).ToLocalChecked());
+  return Napi::String::New(info.Env(), version);
 }
 
 /*
   Get available input/output file/buffer/stream formats
 */
-NAN_METHOD(format) {
-  HandleScope();
-
-  // Attribute names
-  Local<String> attrId = New("id").ToLocalChecked();
-  Local<String> attrInput = New("input").ToLocalChecked();
-  Local<String> attrOutput = New("output").ToLocalChecked();
-  Local<String> attrFile = New("file").ToLocalChecked();
-  Local<String> attrBuffer = New("buffer").ToLocalChecked();
-  Local<String> attrStream = New("stream").ToLocalChecked();
-
-  // Which load/save operations are available for each compressed format?
-  Local<Object> format = New<Object>();
-  for (std::string f : {
-    "jpeg", "png", "webp", "tiff", "magick", "openslide", "dz", "ppm", "fits", "gif", "svg", "pdf", "v"
+Napi::Value format(const Napi::CallbackInfo& info) {
+  Napi::Env env = info.Env();
+  Napi::Object format = Napi::Object::New(env);
+  for (std::string const f : {
+    "jpeg", "png", "webp", "tiff", "magick", "openslide", "dz",
+    "ppm", "fits", "gif", "svg", "heif", "pdf", "vips", "jp2k"
   }) {
     // Input
-    Local<Boolean> hasInputFile =
-      New<Boolean>(vips_type_find("VipsOperation", (f + "load").c_str()));
-    Local<Boolean> hasInputBuffer =
-      New<Boolean>(vips_type_find("VipsOperation", (f + "load_buffer").c_str()));
-    Local<Object> input = New<Object>();
-    Set(input, attrFile, hasInputFile);
-    Set(input, attrBuffer, hasInputBuffer);
-    Set(input, attrStream, hasInputBuffer);
+    Napi::Boolean hasInputFile =
+      Napi::Boolean::New(env, vips_type_find("VipsOperation", (f + "load").c_str()));
+    Napi::Boolean hasInputBuffer =
+      Napi::Boolean::New(env, vips_type_find("VipsOperation", (f + "load_buffer").c_str()));
+    Napi::Object input = Napi::Object::New(env);
+    input.Set("file", hasInputFile);
+    input.Set("buffer", hasInputBuffer);
+    input.Set("stream", hasInputBuffer);
     // Output
-    Local<Boolean> hasOutputFile =
-      New<Boolean>(vips_type_find("VipsOperation", (f + "save").c_str()));
-    Local<Boolean> hasOutputBuffer =
-      New<Boolean>(vips_type_find("VipsOperation", (f + "save_buffer").c_str()));
-    Local<Object> output = New<Object>();
-    Set(output, attrFile, hasOutputFile);
-    Set(output, attrBuffer, hasOutputBuffer);
-    Set(output, attrStream, hasOutputBuffer);
+    Napi::Boolean hasOutputFile =
+      Napi::Boolean::New(env, vips_type_find("VipsOperation", (f + "save").c_str()));
+    Napi::Boolean hasOutputBuffer =
+      Napi::Boolean::New(env, vips_type_find("VipsOperation", (f + "save_buffer").c_str()));
+    Napi::Object output = Napi::Object::New(env);
+    output.Set("file", hasOutputFile);
+    output.Set("buffer", hasOutputBuffer);
+    output.Set("stream", hasOutputBuffer);
     // Other attributes
-    Local<Object> container = New<Object>();
-    Local<String> formatId = New(f).ToLocalChecked();
-    Set(container, attrId, formatId);
-    Set(container, attrInput, input);
-    Set(container, attrOutput, output);
+    Napi::Object container = Napi::Object::New(env);
+    container.Set("id", f);
+    container.Set("input", input);
+    container.Set("output", output);
     // Add to set of formats
-    Set(format, formatId, container);
+    format.Set(f, container);
   }
 
   // Raw, uncompressed data
-  Local<Object> raw = New<Object>();
-  Local<String> rawId = New("raw").ToLocalChecked();
-  Set(raw, attrId, rawId);
-  Set(format, rawId, raw);
-  Local<Boolean> supported = New<Boolean>(true);
-  Local<Boolean> unsupported = New<Boolean>(false);
-  Local<Object> rawInput = New<Object>();
-  Set(rawInput, attrFile, unsupported);
-  Set(rawInput, attrBuffer, supported);
-  Set(rawInput, attrStream, supported);
-  Set(raw, attrInput, rawInput);
-  Local<Object> rawOutput = New<Object>();
-  Set(rawOutput, attrFile, unsupported);
-  Set(rawOutput, attrBuffer, supported);
-  Set(rawOutput, attrStream, supported);
-  Set(raw, attrOutput, rawOutput);
+  Napi::Boolean supported = Napi::Boolean::New(env, true);
+  Napi::Boolean unsupported = Napi::Boolean::New(env, false);
+  Napi::Object rawInput = Napi::Object::New(env);
+  rawInput.Set("file", unsupported);
+  rawInput.Set("buffer", supported);
+  rawInput.Set("stream", supported);
+  Napi::Object rawOutput = Napi::Object::New(env);
+  rawOutput.Set("file", unsupported);
+  rawOutput.Set("buffer", supported);
+  rawOutput.Set("stream", supported);
+  Napi::Object raw = Napi::Object::New(env);
+  raw.Set("id", "raw");
+  raw.Set("input", rawInput);
+  raw.Set("output", rawOutput);
+  format.Set("raw", raw);
 
-  info.GetReturnValue().Set(format);
+  return format;
 }
 
 /*
@@ -207,65 +169,75 @@ NAN_METHOD(format) {
   Calculates the maximum colour distance using the DE2000 algorithm
   between two images of the same dimensions and number of channels.
 */
-NAN_METHOD(_maxColourDistance) {
-  using vips::VImage;
-  using vips::VError;
-  using sharp::DetermineImageType;
-  using sharp::ImageType;
-  using sharp::HasAlpha;
-
-  HandleScope();
+Napi::Value _maxColourDistance(const Napi::CallbackInfo& info) {
+  Napi::Env env = info.Env();
 
   // Open input files
   VImage image1;
-  ImageType imageType1 = DetermineImageType(*Utf8String(info[0]));
-  if (imageType1 != ImageType::UNKNOWN) {
+  sharp::ImageType imageType1 = sharp::DetermineImageType(info[0].As<Napi::String>().Utf8Value().data());
+  if (imageType1 != sharp::ImageType::UNKNOWN) {
     try {
-      image1 = VImage::new_from_file(*Utf8String(info[0]));
+      image1 = VImage::new_from_file(info[0].As<Napi::String>().Utf8Value().c_str());
     } catch (...) {
-      return ThrowError("Input file 1 has corrupt header");
+      throw Napi::Error::New(env, "Input file 1 has corrupt header");
     }
   } else {
-    return ThrowError("Input file 1 is of an unsupported image format");
+    throw Napi::Error::New(env, "Input file 1 is of an unsupported image format");
   }
   VImage image2;
-  ImageType imageType2 = DetermineImageType(*Utf8String(info[1]));
-  if (imageType2 != ImageType::UNKNOWN) {
+  sharp::ImageType imageType2 = sharp::DetermineImageType(info[1].As<Napi::String>().Utf8Value().data());
+  if (imageType2 != sharp::ImageType::UNKNOWN) {
     try {
-      image2 = VImage::new_from_file(*Utf8String(info[1]));
+      image2 = VImage::new_from_file(info[1].As<Napi::String>().Utf8Value().c_str());
     } catch (...) {
-      return ThrowError("Input file 2 has corrupt header");
+      throw Napi::Error::New(env, "Input file 2 has corrupt header");
     }
   } else {
-    return ThrowError("Input file 2 is of an unsupported image format");
+    throw Napi::Error::New(env, "Input file 2 is of an unsupported image format");
   }
   // Ensure same number of channels
   if (image1.bands() != image2.bands()) {
-    return ThrowError("mismatchedBands");
+    throw Napi::Error::New(env, "mismatchedBands");
   }
   // Ensure same dimensions
   if (image1.width() != image2.width() || image1.height() != image2.height()) {
-    return ThrowError("mismatchedDimensions");
+    throw Napi::Error::New(env, "mismatchedDimensions");
   }
 
   double maxColourDistance;
   try {
     // Premultiply and remove alpha
-    if (HasAlpha(image1)) {
+    if (sharp::HasAlpha(image1)) {
       image1 = image1.premultiply().extract_band(1, VImage::option()->set("n", image1.bands() - 1));
     }
-    if (HasAlpha(image2)) {
+    if (sharp::HasAlpha(image2)) {
       image2 = image2.premultiply().extract_band(1, VImage::option()->set("n", image2.bands() - 1));
     }
     // Calculate colour distance
     maxColourDistance = image1.dE00(image2).max();
-  } catch (VError err) {
-    return ThrowError(err.what());
+  } catch (vips::VError const &err) {
+    throw Napi::Error::New(env, err.what());
   }
 
   // Clean up libvips' per-request data and threads
   vips_error_clear();
   vips_thread_shutdown();
 
-  info.GetReturnValue().Set(New<Number>(maxColourDistance));
+  return Napi::Number::New(env, maxColourDistance);
 }
+
+#if defined(__GNUC__)
+// mallctl will be resolved by the runtime linker when jemalloc is being used
+extern "C" {
+  int mallctl(const char *name, void *oldp, size_t *oldlenp, void *newp, size_t newlen) __attribute__((weak));
+}
+Napi::Value _isUsingJemalloc(const Napi::CallbackInfo& info) {
+  Napi::Env env = info.Env();
+  return Napi::Boolean::New(env, mallctl != nullptr);
+}
+#else
+Napi::Value _isUsingJemalloc(const Napi::CallbackInfo& info) {
+  Napi::Env env = info.Env();
+  return Napi::Boolean::New(env, false);
+}
+#endif

src/utilities.h

@@ -1,4 +1,4 @@
-// Copyright 2013, 2014, 2015, 2016, 2017 Lovell Fuller and contributors.
+// Copyright 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Lovell Fuller and contributors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -15,14 +15,15 @@
 #ifndef SRC_UTILITIES_H_
 #define SRC_UTILITIES_H_
 
-#include <nan.h>
+#include <napi.h>
 
-NAN_METHOD(cache);
-NAN_METHOD(concurrency);
-NAN_METHOD(counters);
-NAN_METHOD(simd);
-NAN_METHOD(libvipsVersion);
-NAN_METHOD(format);
-NAN_METHOD(_maxColourDistance);
+Napi::Value cache(const Napi::CallbackInfo& info);
+Napi::Value concurrency(const Napi::CallbackInfo& info);
+Napi::Value counters(const Napi::CallbackInfo& info);
+Napi::Value simd(const Napi::CallbackInfo& info);
+Napi::Value libvipsVersion(const Napi::CallbackInfo& info);
+Napi::Value format(const Napi::CallbackInfo& info);
+Napi::Value _maxColourDistance(const Napi::CallbackInfo& info);
+Napi::Value _isUsingJemalloc(const Napi::CallbackInfo& info);
 
 #endif  // SRC_UTILITIES_H_

test/bench/package.json

@@ -8,19 +8,18 @@
     "test": "node perf && node random && node parallel"
   },
   "devDependencies": {
-    "async": "^2.6.0",
-    "benchmark": "^2.1.4",
-    "gm": "^1.23.1",
-    "imagemagick": "^0.1.3",
-    "imagemagick-native": "^1.9.3",
-    "images": "^3.0.1",
-    "jimp": "^0.2.28",
-    "mapnik": "^3.6.2",
-    "pajk-lwip": "^0.2.0",
-    "semver": "^5.4.1"
+    "@squoosh/cli": "0.7.2",
+    "@squoosh/lib": "0.4.0",
+    "async": "3.2.1",
+    "benchmark": "2.1.4",
+    "gm": "1.23.1",
+    "imagemagick": "0.1.3",
+    "jimp": "0.16.1",
+    "mapnik": "4.5.8",
+    "semver": "7.3.5"
   },
   "license": "Apache-2.0",
   "engines": {
-    "node": ">=4"
+    "node": "16"
   }
 }

test/bench/perf.js

@@ -1,6 +1,8 @@
 'use strict';
 
+const os = require('os');
 const fs = require('fs');
+const { exec } = require('child_process');
 
 const async = require('async');
 const assert = require('assert');
@@ -12,37 +14,25 @@ const gm = require('gm');
 const imagemagick = require('imagemagick');
 const mapnik = require('mapnik');
 const jimp = require('jimp');
-let images;
-try {
-  images = require('images');
-} catch (err) {
-  console.log('Excluding node-images');
-}
-let imagemagickNative;
-try {
-  imagemagickNative = require('imagemagick-native');
-} catch (err) {
-  console.log('Excluding imagemagick-native');
-}
-let lwip;
-try {
-  lwip = require('pajk-lwip');
-} catch (err) {
-  console.log('Excluding lwip');
-}
+const squoosh = require('@squoosh/lib');
 
 const fixtures = require('../fixtures');
 
+const outputJpg = fixtures.path('output.jpg');
+const outputPng = fixtures.path('output.png');
+const outputWebP = fixtures.path('output.webp');
+
 const width = 720;
 const height = 588;
 
 // Disable libvips cache to ensure tests are as fair as they can be
 sharp.cache(false);
-// Enable use of SIMD
-sharp.simd(true);
+
+// Spawn one thread per CPU
+sharp.concurrency(os.cpus().length);
 
 async.series({
-  'jpeg': function (callback) {
+  jpeg: function (callback) {
     const inputJpgBuffer = fs.readFileSync(fixtures.inputJpg);
     const jpegSuite = new Benchmark.Suite('jpeg');
     // jimp
@@ -54,7 +44,7 @@ async.series({
             throw err;
           } else {
             image
-              .resize(width, height)
+              .resize(width, height, jimp.RESIZE_BICUBIC)
               .quality(80)
               .getBuffer(jimp.MIME_JPEG, function (err) {
                 if (err) {
@@ -74,9 +64,9 @@ async.series({
             throw err;
           } else {
             image
-              .resize(width, height)
+              .resize(width, height, jimp.RESIZE_BICUBIC)
               .quality(80)
-              .write(fixtures.outputJpg, function (err) {
+              .write(outputJpg, function (err) {
                 if (err) {
                   throw err;
                 } else {
@@ -87,51 +77,65 @@ async.series({
         });
       }
     });
-    // lwip
-    if (typeof lwip !== 'undefined') {
-      jpegSuite.add('lwip-file-file', {
-        defer: true,
-        fn: function (deferred) {
-          lwip.open(fixtures.inputJpg, function (err, image) {
-            if (err) {
-              throw err;
-            }
-            image.resize(width, height, 'lanczos', function (err, image) {
-              if (err) {
-                throw err;
+    // squoosh-cli
+    jpegSuite.add('squoosh-cli-file-file', {
+      defer: true,
+      fn: function (deferred) {
+        exec(`./node_modules/.bin/squoosh-cli \
+          --output-dir ${os.tmpdir()} \
+          --resize '{"enabled":true,"width":${width},"height":${height},"method":"lanczos3","premultiply":false,"linearRGB":false}' \
+          --mozjpeg '{"quality":80,"progressive":false,"optimize_coding":true,"quant_table":0,"trellis_multipass":false,"chroma_subsample":2,"separate_chroma_quality":false}' \
+          "${fixtures.inputJpg}"`, function (err) {
+          if (err) {
+            throw err;
+          }
+          deferred.resolve();
+        });
+      }
+    });
+    // squoosh-lib (GPLv3)
+    jpegSuite.add('squoosh-lib-buffer-buffer', {
+      defer: true,
+      fn: function (deferred) {
+        const pool = new squoosh.ImagePool();
+        const image = pool.ingestImage(inputJpgBuffer);
+        image.decoded
+          .then(function () {
+            return image.preprocess({
+              resize: {
+                enabled: true,
+                width,
+                height,
+                method: 'lanczos3',
+                premultiply: false,
+                linearRGB: false
               }
-              image.writeFile(fixtures.outputJpg, {quality: 80}, function (err) {
-                if (err) {
-                  throw err;
-                }
-                deferred.resolve();
-              });
             });
-          });
-        }
-      }).add('lwip-buffer-buffer', {
-        defer: true,
-        fn: function (deferred) {
-          lwip.open(inputJpgBuffer, 'jpg', function (err, image) {
-            if (err) {
-              throw err;
-            }
-            image.resize(width, height, 'lanczos', function (err, image) {
-              if (err) {
-                throw err;
+          })
+          .then(function () {
+            return image.encode({
+              mozjpeg: {
+                quality: 80,
+                progressive: false,
+                optimize_coding: true,
+                quant_table: 0,
+                trellis_multipass: false,
+                chroma_subsample: 2,
+                separate_chroma_quality: false
               }
-              image.toBuffer('jpg', {quality: 80}, function (err, buffer) {
-                if (err) {
-                  throw err;
-                }
-                assert.notStrictEqual(null, buffer);
-                deferred.resolve();
-              });
             });
+          })
+          .then(function () {
+            return pool.close();
+          })
+          .then(function () {
+            return image.encodedWith.mozjpeg;
+          })
+          .then(function () {
+            deferred.resolve();
           });
-        }
-      });
-    }
+      }
+    });
     // mapnik
     jpegSuite.add('mapnik-file-file', {
       defer: true,
@@ -142,7 +146,7 @@ async.series({
             .resize(width, height, {
               scaling_method: mapnik.imageScaling.lanczos
             })
-            .save(fixtures.outputJpg, 'jpeg:quality=80', function (err) {
+            .save(outputJpg, 'jpeg:quality=80', function (err) {
               if (err) throw err;
               deferred.resolve();
             });
@@ -170,7 +174,7 @@ async.series({
       fn: function (deferred) {
         imagemagick.resize({
           srcPath: fixtures.inputJpg,
-          dstPath: fixtures.outputJpg,
+          dstPath: outputJpg,
           quality: 0.8,
           width: width,
           height: height,
@@ -185,29 +189,6 @@ async.series({
         });
       }
     });
-    // imagemagick-native
-    if (typeof imagemagickNative !== 'undefined') {
-      jpegSuite.add('imagemagick-native-buffer-buffer', {
-        defer: true,
-        fn: function (deferred) {
-          imagemagickNative.convert({
-            srcData: inputJpgBuffer,
-            quality: 80,
-            width: width,
-            height: height,
-            format: 'JPEG',
-            filter: 'Lanczos'
-          }, function (err, buffer) {
-            if (err) {
-              throw err;
-            } else {
-              assert.notStrictEqual(null, buffer);
-              deferred.resolve();
-            }
-          });
-        }
-      });
-    }
     // gm
     jpegSuite.add('gm-buffer-file', {
       defer: true,
@@ -216,7 +197,7 @@ async.series({
           .filter('Lanczos')
           .resize(width, height)
           .quality(80)
-          .write(fixtures.outputJpg, function (err) {
+          .write(outputJpg, function (err) {
             if (err) {
               throw err;
             } else {
@@ -247,7 +228,7 @@ async.series({
           .filter('Lanczos')
           .resize(width, height)
           .quality(80)
-          .write(fixtures.outputJpg, function (err) {
+          .write(outputJpg, function (err) {
             if (err) {
               throw err;
             } else {
@@ -272,21 +253,13 @@ async.series({
           });
       }
     });
-    // images
-    if (typeof images !== 'undefined') {
-      jpegSuite.add('images-file-file', function () {
-        images(fixtures.inputJpg)
-          .resize(width, height)
-          .save(fixtures.outputJpg, { quality: 80 });
-      });
-    }
     // sharp
     jpegSuite.add('sharp-buffer-file', {
       defer: true,
       fn: function (deferred) {
         sharp(inputJpgBuffer)
           .resize(width, height)
-          .toFile(fixtures.outputJpg, function (err) {
+          .toFile(outputJpg, function (err) {
             if (err) {
               throw err;
             } else {
@@ -313,7 +286,7 @@ async.series({
       fn: function (deferred) {
         sharp(fixtures.inputJpg)
           .resize(width, height)
-          .toFile(fixtures.outputJpg, function (err) {
+          .toFile(outputJpg, function (err) {
             if (err) {
               throw err;
             } else {
@@ -325,7 +298,7 @@ async.series({
       defer: true,
       fn: function (deferred) {
         const readable = fs.createReadStream(fixtures.inputJpg);
-        const writable = fs.createWriteStream(fixtures.outputJpg);
+        const writable = fs.createWriteStream(outputJpg);
         writable.on('finish', function () {
           deferred.resolve();
         });
@@ -356,6 +329,9 @@ async.series({
           .then(function (buffer) {
             assert.notStrictEqual(null, buffer);
             deferred.resolve();
+          })
+          .catch(function (err) {
+            throw err;
           });
       }
     }).on('cycle', function (event) {
@@ -553,8 +529,7 @@ async.series({
     }).add('sharp-sequentialRead', {
       defer: true,
       fn: function (deferred) {
-        sharp(inputJpgBuffer)
-          .sequentialRead()
+        sharp(inputJpgBuffer, { sequentialRead: true })
           .resize(width, height)
           .toBuffer(function (err, buffer) {
             if (err) {
@@ -569,8 +544,10 @@ async.series({
       defer: true,
       fn: function (deferred) {
         sharp(inputJpgBuffer)
-          .resize(width, height)
-          .crop(sharp.strategy.entropy)
+          .resize(width, height, {
+            fit: 'cover',
+            position: sharp.strategy.entropy
+          })
           .toBuffer(function (err, buffer) {
             if (err) {
               throw err;
@@ -584,8 +561,10 @@ async.series({
       defer: true,
       fn: function (deferred) {
         sharp(inputJpgBuffer)
-          .resize(width, height)
-          .crop(sharp.strategy.attention)
+          .resize(width, height, {
+            fit: 'cover',
+            position: sharp.strategy.attention
+          })
           .toBuffer(function (err, buffer) {
             if (err) {
               throw err;
@@ -654,8 +633,9 @@ async.series({
   },
   // PNG
   png: function (callback) {
-    const inputPngBuffer = fs.readFileSync(fixtures.inputPng);
+    const inputPngBuffer = fs.readFileSync(fixtures.inputPngAlphaPremultiplicationLarge);
     const pngSuite = new Benchmark.Suite('png');
+    const minSamples = 64;
     // jimp
     pngSuite.add('jimp-buffer-buffer', {
       defer: true,
@@ -666,6 +646,8 @@ async.series({
           } else {
             image
               .resize(width, height)
+              .deflateLevel(6)
+              .filterType(0)
               .getBuffer(jimp.MIME_PNG, function (err) {
                 if (err) {
                   throw err;
@@ -679,13 +661,15 @@ async.series({
     }).add('jimp-file-file', {
       defer: true,
       fn: function (deferred) {
-        jimp.read(fixtures.inputPng, function (err, image) {
+        jimp.read(fixtures.inputPngAlphaPremultiplicationLarge, function (err, image) {
           if (err) {
             throw err;
           } else {
             image
               .resize(width, height)
-              .write(fixtures.outputPng, function (err) {
+              .deflateLevel(6)
+              .filterType(0)
+              .write(outputPng, function (err) {
                 if (err) {
                   throw err;
                 } else {
@@ -696,36 +680,11 @@ async.series({
         });
       }
     });
-    // lwip
-    if (typeof lwip !== 'undefined') {
-      pngSuite.add('lwip-buffer-buffer', {
-        defer: true,
-        fn: function (deferred) {
-          lwip.open(inputPngBuffer, 'png', function (err, image) {
-            if (err) {
-              throw err;
-            }
-            image.resize(width, height, 'lanczos', function (err, image) {
-              if (err) {
-                throw err;
-              }
-              image.toBuffer('png', function (err, buffer) {
-                if (err) {
-                  throw err;
-                }
-                assert.notStrictEqual(null, buffer);
-                deferred.resolve();
-              });
-            });
-          });
-        }
-      });
-    }
     // mapnik
     pngSuite.add('mapnik-file-file', {
       defer: true,
       fn: function (deferred) {
-        mapnik.Image.open(fixtures.inputPng, function (err, img) {
+        mapnik.Image.open(fixtures.inputPngAlphaPremultiplicationLarge, function (err, img) {
           if (err) throw err;
           img.premultiply(function (err, img) {
             if (err) throw err;
@@ -735,7 +694,7 @@ async.series({
               if (err) throw err;
               img.demultiply(function (err, img) {
                 if (err) throw err;
-                img.save(fixtures.outputPng, 'png', function (err) {
+                img.save(outputPng, 'png', function (err) {
                   if (err) throw err;
                   deferred.resolve();
                 });
@@ -772,11 +731,15 @@ async.series({
       defer: true,
       fn: function (deferred) {
         imagemagick.resize({
-          srcPath: fixtures.inputPng,
-          dstPath: fixtures.outputPng,
+          srcPath: fixtures.inputPngAlphaPremultiplicationLarge,
+          dstPath: outputPng,
           width: width,
           height: height,
-          filter: 'Lanczos'
+          filter: 'Lanczos',
+          customArgs: [
+            '-define', 'PNG:compression-level=6',
+            '-define', 'PNG:compression-filter=0'
+          ]
         }, function (err) {
           if (err) {
             throw err;
@@ -786,30 +749,16 @@ async.series({
         });
       }
     });
-    // imagemagick-native
-    if (typeof imagemagickNative !== 'undefined') {
-      pngSuite.add('imagemagick-native-buffer-buffer', {
-        defer: true,
-        fn: function (deferred) {
-          imagemagickNative.convert({
-            srcData: inputPngBuffer,
-            width: width,
-            height: height,
-            format: 'PNG',
-            filter: 'Lanczos'
-          });
-          deferred.resolve();
-        }
-      });
-    }
     // gm
     pngSuite.add('gm-file-file', {
       defer: true,
       fn: function (deferred) {
-        gm(fixtures.inputPng)
+        gm(fixtures.inputPngAlphaPremultiplicationLarge)
           .filter('Lanczos')
           .resize(width, height)
-          .write(fixtures.outputPng, function (err) {
+          .define('PNG:compression-level=6')
+          .define('PNG:compression-filter=0')
+          .write(outputPng, function (err) {
             if (err) {
               throw err;
             } else {
@@ -820,9 +769,11 @@ async.series({
     }).add('gm-file-buffer', {
       defer: true,
       fn: function (deferred) {
-        gm(fixtures.inputPng)
+        gm(fixtures.inputPngAlphaPremultiplicationLarge)
           .filter('Lanczos')
           .resize(width, height)
+          .define('PNG:compression-level=6')
+          .define('PNG:compression-filter=0')
           .toBuffer(function (err, buffer) {
             if (err) {
               throw err;
@@ -833,21 +784,15 @@ async.series({
           });
       }
     });
-    // images
-    if (typeof images !== 'undefined') {
-      pngSuite.add('images-file-file', function () {
-        images(fixtures.inputPng)
-          .resize(width, height)
-          .save(fixtures.outputPng);
-      });
-    }
     // sharp
     pngSuite.add('sharp-buffer-file', {
       defer: true,
+      minSamples,
       fn: function (deferred) {
         sharp(inputPngBuffer)
           .resize(width, height)
-          .toFile(fixtures.outputPng, function (err) {
+          .png({ compressionLevel: 6 })
+          .toFile(outputPng, function (err) {
             if (err) {
               throw err;
             } else {
@@ -857,9 +802,11 @@ async.series({
       }
     }).add('sharp-buffer-buffer', {
       defer: true,
+      minSamples,
       fn: function (deferred) {
         sharp(inputPngBuffer)
           .resize(width, height)
+          .png({ compressionLevel: 6 })
           .toBuffer(function (err, buffer) {
             if (err) {
               throw err;
@@ -871,10 +818,12 @@ async.series({
       }
     }).add('sharp-file-file', {
       defer: true,
+      minSamples,
       fn: function (deferred) {
-        sharp(fixtures.inputPng)
+        sharp(fixtures.inputPngAlphaPremultiplicationLarge)
           .resize(width, height)
-          .toFile(fixtures.outputPng, function (err) {
+          .png({ compressionLevel: 6 })
+          .toFile(outputPng, function (err) {
             if (err) {
               throw err;
             } else {
@@ -884,9 +833,11 @@ async.series({
       }
     }).add('sharp-file-buffer', {
       defer: true,
+      minSamples,
       fn: function (deferred) {
-        sharp(fixtures.inputPng)
+        sharp(fixtures.inputPngAlphaPremultiplicationLarge)
           .resize(width, height)
+          .png({ compressionLevel: 6 })
           .toBuffer(function (err, buffer) {
             if (err) {
               throw err;
@@ -898,10 +849,11 @@ async.series({
       }
     }).add('sharp-progressive', {
       defer: true,
+      minSamples,
       fn: function (deferred) {
         sharp(inputPngBuffer)
           .resize(width, height)
-          .png({ progressive: true })
+          .png({ compressionLevel: 6, progressive: true })
           .toBuffer(function (err, buffer) {
             if (err) {
               throw err;
@@ -913,10 +865,27 @@ async.series({
       }
     }).add('sharp-adaptiveFiltering', {
       defer: true,
+      minSamples,
       fn: function (deferred) {
         sharp(inputPngBuffer)
           .resize(width, height)
-          .png({ adaptiveFiltering: true })
+          .png({ adaptiveFiltering: true, compressionLevel: 6 })
+          .toBuffer(function (err, buffer) {
+            if (err) {
+              throw err;
+            } else {
+              assert.notStrictEqual(null, buffer);
+              deferred.resolve();
+            }
+          });
+      }
+    }).add('sharp-compressionLevel=9', {
+      defer: true,
+      minSamples,
+      fn: function (deferred) {
+        sharp(inputPngBuffer)
+          .resize(width, height)
+          .png({ compressionLevel: 9 })
           .toBuffer(function (err, buffer) {
             if (err) {
               throw err;
@@ -941,7 +910,7 @@ async.series({
       fn: function (deferred) {
         sharp(inputWebPBuffer)
           .resize(width, height)
-          .toFile(fixtures.outputWebP, function (err) {
+          .toFile(outputWebP, function (err) {
             if (err) {
               throw err;
             } else {
@@ -968,7 +937,7 @@ async.series({
       fn: function (deferred) {
         sharp(fixtures.inputWebP)
           .resize(width, height)
-          .toFile(fixtures.outputWebP, function (err) {
+          .toFile(outputWebP, function (err) {
             if (err) {
               throw err;
             } else {

test/bench/random.js

@@ -23,7 +23,7 @@ new Benchmark.Suite('random').add('imagemagick', {
   fn: function (deferred) {
     imagemagick.resize({
       srcPath: fixtures.inputJpg,
-      dstPath: fixtures.outputJpg,
+      dstPath: fixtures.path('output.jpg'),
       quality: 0.8,
       width: randomDimension(),
       height: randomDimension(),

test/fixtures/circle.svg

@@ -0,0 +1,3 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 8 8">
+      <circle r="3.75" cx="4" cy="4" fill="deeppink" />
+</svg>