v0.11.3

Convert blur and sharpen parameters to double instead of int.
This was broken during the nan v2 upgrade by commit b7e0a6f.

.gitignore

@@ -2,7 +2,7 @@ build
 node_modules
 coverage
 test/bench/node_modules
-test/fixtures/output.*
+test/fixtures/output*
 test/leak/libvips.supp
 
 # Mac OS X

.jshintrc

@@ -2,8 +2,9 @@
   "strict": true,
   "node": true,
   "maxparams": 4,
-  "maxcomplexity": 11,
+  "maxcomplexity": 13,
   "globals": {
+    "before": true,
     "describe": true,
     "it": true
   }

.npmignore

@@ -6,3 +6,5 @@ coverage
 .gitignore
 test
 .travis.yml
+appveyor.yml
+mkdocs.yml

.travis.yml

@@ -2,8 +2,16 @@ language: node_js
 node_js:
   - "0.10"
   - "0.12"
-  - iojs
+  - "iojs-v2"
+  - "iojs-v3"
+addons:
+  apt:
+    sources:
+    - ubuntu-toolchain-r-test
+    packages:
+    - g++-4.8
 before_install:
+  - sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.8 90
   - curl -s https://raw.githubusercontent.com/lovell/sharp/master/preinstall.sh | sudo bash -
 after_success:
   - cat ./coverage/lcov.info | ./node_modules/coveralls/bin/coveralls.js

CONTRIBUTING.md

@@ -30,9 +30,16 @@ 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`.
+
 ## Submit a Pull Request with a new feature
 
-Please add JavaScript [unit tests](https://github.com/lovell/sharp/tree/master/test/unit) to cover your new feature. A test coverage report for the JavaScript code is generated in the `coverage/lcov-report` directory.
+Please add JavaScript [unit tests](https://github.com/lovell/sharp/tree/master/test/unit) to cover your new feature.
+A test coverage report for the JavaScript code is generated in the `coverage/lcov-report` directory.
+
+Where possible, the functional tests use gradient-based perceptual hashes
+based on [dHash](http://www.hackerfactor.com/blog/index.php?/archives/529-Kind-of-Like-That.html)
+to compare expected vs actual images.
 
 You deserve to add your details to the [list of contributors](https://github.com/lovell/sharp/blob/master/package.json#L5).
 
@@ -40,9 +47,9 @@ Any change that modifies the existing public API should be added to the relevant
 
 | Release | WIP branch |
 | ------: | :--------- |
-|  v0.9.0 | intake     |
-| v0.10.0 | judgement  |
 | v0.11.0 | knife      |
+| v0.12.0 | look       |
+| v0.13.0 | mind       |
 
 Please squash your changes into a single commit using a command like `git rebase -i upstream/<wip-branch>`.
 
@@ -72,11 +79,10 @@ npm test
 
 ### Memory leak tests
 
-Requires _valgrind_.
+Requires [Valgrind](http://valgrind.org/).
 
 ```sh
-cd sharp/test/leak
-./leak.sh
+npm run test-leak
 ```
 
 ## Finally

README.md

@@ -1,642 +1,30 @@
 # sharp
 
-* [Installation](https://github.com/lovell/sharp#installation)
-* [Usage examples](https://github.com/lovell/sharp#usage-examples)
-* [API](https://github.com/lovell/sharp#api)
-* [Contributing](https://github.com/lovell/sharp#contributing)
-* [Testing](https://github.com/lovell/sharp#testing)
-* [Performance](https://github.com/lovell/sharp#performance)
-* [Thanks](https://github.com/lovell/sharp#thanks)
-* [Licence](https://github.com/lovell/sharp#licence)
-
-The typical use case for this high speed Node.js module is to convert large images of many formats to smaller, web-friendly JPEG, PNG and WebP images of varying dimensions.
-
-This module supports reading and writing JPEG, PNG and WebP images to and from Streams, Buffer objects and the filesystem.
-It also supports reading images of many other types from the filesystem via libmagick or libgraphicsmagick if present.
-Colour spaces, embedded ICC profiles and alpha transparency channels are all handled correctly.
-
-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. Resizing an image is typically 4x faster than using the quickest ImageMagick and GraphicsMagick settings.
-
-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 can be disabled, which for diagrams and line art often produces the same result as [pngcrush](http://pmt.sourceforge.net/pngcrush/).
-
-Everything remains non-blocking thanks to _libuv_, no child processes are spawned and Promises/A+ are supported.
-
-Anyone who has used the Node.js bindings for [GraphicsMagick](https://github.com/aheckmann/gm) will find the API similarly fluent.
-
-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).
-
-## Installation
-
-	npm install sharp
-
-### Prerequisites
-
-* Node.js v0.10+
-* [libvips](https://github.com/jcupitt/libvips) v7.40.0+ (7.42.0+ recommended)
-
-To install the most suitable version of libvips on the following Operating Systems:
-
-* Mac OS
-  * Homebrew
-  * MacPorts
-* Debian Linux
-  * Debian 7, 8
-  * Ubuntu 12.04, 14.04, 14.10, 15.04
-  * Mint 13, 17
-* Red Hat Linux
-  * RHEL/Centos/Scientific 6, 7
-  * Fedora 21, 22
-  * Amazon Linux 2014.09
-
-run the following as a user with `sudo` access:
-
-	curl -s https://raw.githubusercontent.com/lovell/sharp/master/preinstall.sh | sudo bash -
-
-or run the following as `root`:
-
-	curl -s https://raw.githubusercontent.com/lovell/sharp/master/preinstall.sh | bash -
-
-The [preinstall.sh](https://github.com/lovell/sharp/blob/master/preinstall.sh) script requires `curl` and `pkg-config`.
-
-### Mac OS tips
-
-Manual install via homebrew:
-
-	brew install homebrew/science/vips --with-webp --with-graphicsmagick
-
-A missing or incorrectly configured _Xcode Command Line Tools_ installation [can lead](https://github.com/lovell/sharp/issues/80) to a `library not found for -ljpeg` error. If so, please try:
-
-	xcode-select --install
-
-The _gettext_ dependency of _libvips_ [can lead](https://github.com/lovell/sharp/issues/9) to a `library not found for -lintl` error. If so, please try:
-
-	brew link gettext --force
-
-### Heroku
-
-[Alessandro Tagliapietra](https://github.com/alex88) maintains an [Heroku buildpack for libvips](https://github.com/alex88/heroku-buildpack-vips) and its dependencies.
-
-### Docker
-
-[Marc Bachmann](https://github.com/marcbachmann) maintains a [Dockerfile for libvips](https://github.com/marcbachmann/dockerfile-libvips).
-
-	docker pull marcbachmann/libvips
-
-### Build tools
-
-* [gulp-responsive](https://www.npmjs.com/package/gulp-responsive)
-* [gulp-sharp](https://www.npmjs.com/package/gulp-sharp)
-* [grunt-sharp](https://www.npmjs.com/package/grunt-sharp)
-
-## Usage examples
-
-```javascript
-var sharp = require('sharp');
-```
-
-```javascript
-sharp('input.jpg').resize(300, 200).toFile('output.jpg', function(err) {
-  if (err) {
-    throw err;
-  }
-  // output.jpg is a 300 pixels wide and 200 pixels high image
-  // containing a scaled and cropped version of input.jpg
-});
-```
-
-```javascript
-var transformer = sharp().resize(300, 200).crop(sharp.gravity.north);
-readableStream.pipe(transformer).pipe(writableStream);
-// Read image data from readableStream, resize and write image data to writableStream
-```
-
-```javascript
-var image = sharp(inputJpg);
-image.metadata(function(err, metadata) {
-  image.resize(Math.floor(metadata.width / 2)).webp().toBuffer(function(err, outputBuffer, info) {
-    // outputBuffer contains a WebP image half the width and height of the original JPEG
-  });
-});
-```
-
-```javascript
-var pipeline = sharp()
-  .rotate()
-  .resize(null, 200)
-  .progressive()
-  .toBuffer(function(err, outputBuffer, info) {
-    if (err) {
-      throw err;
-    }
-    // outputBuffer contains 200px high progressive JPEG image data,
-    // auto-rotated using EXIF Orientation tag
-    // info.width and info.height contain the dimensions of the resized image
-  });
-readableStream.pipe(pipeline);
-```
-
-```javascript
-sharp('input.png')
-  .rotate(180)
-  .resize(300)
-  .flatten()
-  .background('#ff6600')
-  .sharpen()
-  .withMetadata()
-  .quality(90)
-  .webp()
-  .toBuffer()
-  .then(function(outputBuffer) {
-    // outputBuffer contains upside down, 300px wide, alpha channel flattened
-    // onto orange background, sharpened, with metadata, 90% quality WebP image
-    // data
-  });
-```
-
-```javascript
-http.createServer(function(request, response) {
-  response.writeHead(200, {'Content-Type': 'image/webp'});
-  sharp('input.jpg').rotate().resize(200).webp().pipe(response);
-}).listen(8000);
-// Create HTTP server that always returns auto-rotated 'input.jpg',
-// resized to 200 pixels wide, in WebP format
-```
-
-```javascript
-sharp(input)
-  .extract(top, left, width, height)
-  .toFile(output);
-  // Extract a region of the input image, saving in the same format.
-```
-
-```javascript
-sharp(input)
-  .extract(topOffsetPre, leftOffsetPre, widthPre, heightPre)
-  .resize(width, height)
-  .extract(topOffsetPost, leftOffsetPost, widthPost, heightPost)
-  .toFile(output);
-  // Extract a region, resize, then extract from the resized image
-```
-
-```javascript
-sharp(inputBuffer)
-  .resize(200, 300)
-  .interpolateWith(sharp.interpolator.nohalo)
-  .background('white')
-  .embed()
-  .toFile('output.tiff')
-  .then(function() {
-    // output.tiff is a 200 pixels wide and 300 pixels high image
-    // containing a nohalo scaled version, embedded on a white canvas,
-    // of the image data in inputBuffer
-  });
-```
-
-```javascript
-sharp('input.gif')
-  .resize(200, 300)
-  .background({r: 0, g: 0, b: 0, a: 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
-  });
-```
-
-```javascript
-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
-  });
-```
-
-## API
-
-### Input methods
-
-#### sharp([input])
-
-Constructor to which further methods are chained. `input`, if present, can be one of:
-
-* Buffer containing JPEG, PNG, WebP or TIFF image data, or
-* String containing the filename of an image, with most major formats supported.
-
-The object returned implements the [stream.Duplex](http://nodejs.org/api/stream.html#stream_class_stream_duplex) class.
-
-JPEG, PNG, WebP or TIFF format image data can be streamed into the object when `input` is not provided.
-
-JPEG, PNG or WebP format image data can be streamed out from this object.
-
-#### metadata([callback])
-
-Fast access to image metadata without decoding any compressed image data.
-
-`callback`, if present, gets the arguments `(err, metadata)` where `metadata` has the attributes:
-
-* `format`: Name of decoder to be used to decompress image data e.g. `jpeg`, `png`, `webp` (for file-based input additionally `tiff` and `magick`)
-* `width`: Number of pixels wide
-* `height`: Number of pixels high
-* `space`: Name of colour space interpretation e.g. `srgb`, `rgb`, `scrgb`, `cmyk`, `lab`, `xyz`, `b-w` [...](https://github.com/jcupitt/libvips/blob/master/libvips/iofuncs/enumtypes.c#L522)
-* `channels`: Number of bands e.g. `3` for sRGB, `4` for CMYK
-* `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
-
-A Promises/A+ promise is returned when `callback` is not provided.
-
-#### 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.
-
-#### limitInputPixels(pixels)
-
-Do not process input images where the number of pixels (width * height) exceeds this limit.
-
-`pixels` is the integral Number of pixels, with a value between 1 and the default 268402689 (0x3FFF * 0x3FFF).
-
-### Image transformation options
-
-#### resize(width, [height])
-
-Scale output to `width` x `height`. By default, the resized image is cropped to the exact size specified.
-
-`width` is the integral Number of pixels wide the resultant image should be, between 1 and 16383 (0x3FFF). Use `null` or `undefined` to auto-scale the width to match the height.
-
-`height` is the integral Number of pixels high the resultant image should be, between 1 and 16383. Use `null` or `undefined` to auto-scale the height to match the width.
-
-#### extract(top, left, width, height)
-
-Extract a region of the image. Can be used with or without a `resize` operation.
-
-`top` and `left` are the offset, in pixels, from the top-left corner.
-
-`width` and `height` are the dimensions of the extracted image.
-
-Use `extract` before `resize` for pre-resize extraction. Use `extract` after `resize` for post-resize extraction. Use `extract` before and after for both.
-
-#### crop([gravity])
-
-Crop the resized image to the exact size specified, the default behaviour.
-
-`gravity`, if present, is an attribute of the `sharp.gravity` Object e.g. `sharp.gravity.north`.
-
-Possible values are `north`, `east`, `south`, `west`, `center` and `centre`. The default gravity is `center`/`centre`.
-
-#### max()
-
-Preserving aspect ratio, resize the image to the maximum `width` or `height` specified.
-
-Both `width` and `height` must be provided via `resize` otherwise the behaviour will default to `crop`.
-
-#### background(rgba)
-
-Set the background for the `embed` and `flatten` operations.
-
-`rgba` is parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
-
-The alpha value is a float between `0` (transparent) and `1` (opaque).
-
-The default background is `{r: 0, g: 0, b: 0, a: 1}`, black without transparency.
-
-#### 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.
-
-#### flatten()
-
-Merge alpha transparency channel, if any, with `background`.
-
-#### rotate([angle])
-
-Rotate the output image by either an explicit angle or auto-orient based on the EXIF `Orientation` tag.
-
-`angle`, if present, is a Number with a value of `0`, `90`, `180` or `270`.
-
-Use this method without `angle` to determine the angle from EXIF data. Mirroring is supported and may infer the use of a `flip` operation.
-
-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)`.
-
-#### flip()
-
-Flip the image about the vertical Y axis. This always occurs after rotation, if any.
-
-#### flop()
-
-Flop the image about the horizontal X axis. This always occurs after rotation, if any.
-
-#### withoutEnlargement()
-
-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".
-
-#### blur([sigma])
-
-When used without parameters, performs a fast, mild blur of the output image. This typically reduces performance by 10%.
-
-When a `sigma` is provided, performs a slower, more accurate Gaussian blur. This typically reduces performance by 25%.
-
-* `sigma`, if present, is a Number between 0.3 and 1000 representing the approximate blur radius in pixels.
-
-#### sharpen([radius], [flat], [jagged])
-
-When used without parameters, performs a fast, mild sharpen of the output image. This typically reduces performance by 10%.
-
-When a `radius` 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. This typically reduces performance by 50%.
-
-* `radius`, if present, is an integral Number representing the sharpen mask radius in pixels.
-* `flat`, if present, is a Number representing the level of sharpening to apply to "flat" areas, defaulting to a value of 1.0.
-* `jagged`, if present, is a Number representing the level of sharpening to apply to "jagged" areas, defaulting to a value of 2.0.
-
-#### interpolateWith(interpolator)
-
-Use the given interpolator for image resizing, where `interpolator` is an attribute of the `sharp.interpolator` Object e.g. `sharp.interpolator.bicubic`.
-
-Possible interpolators, in order of performance, are:
-
-* `nearest`: Use [nearest neighbour interpolation](http://en.wikipedia.org/wiki/Nearest-neighbor_interpolation), suitable for image enlargement only.
-* `bilinear`: Use [bilinear interpolation](http://en.wikipedia.org/wiki/Bilinear_interpolation), the default and fastest image reduction interpolation.
-* `bicubic`: Use [bicubic interpolation](http://en.wikipedia.org/wiki/Bicubic_interpolation), which typically reduces performance by 5%.
-* `vertexSplitQuadraticBasisSpline`: Use [VSQBS interpolation](https://github.com/jcupitt/libvips/blob/master/libvips/resample/vsqbs.cpp#L48), which prevents "staircasing" and typically reduces performance by 5%.
-* `locallyBoundedBicubic`: Use [LBB interpolation](https://github.com/jcupitt/libvips/blob/master/libvips/resample/lbb.cpp#L100), which prevents some "[acutance](http://en.wikipedia.org/wiki/Acutance)" and typically reduces performance by a factor of 2.
-* `nohalo`: Use [Nohalo interpolation](http://eprints.soton.ac.uk/268086/), which prevents acutance and typically reduces performance by a factor of 3.
-
-#### gamma([gamma])
-
-Apply a gamma correction by reducing the encoding (darken) pre-resize at a factor of `1/gamma` then increasing the encoding (brighten) post-resize at a factor of `gamma`.
-
-`gamma`, if present, is a Number betweem 1 and 3. The default value is `2.2`, a suitable approximation for sRGB images.
-
-This can improve the perceived brightness of a resized image in non-linear colour spaces.
-
-JPEG input images will not take advantage of the shrink-on-load performance optimisation when applying a gamma correction.
-
-#### grayscale() / greyscale()
-
-Convert to 8-bit greyscale; 256 shades of grey.
-
-This is a linear operation. If the input image is in a non-linear colour space such as sRGB, use `gamma()` with `greyscale()` for the best results.
-
-The output image will still be web-friendly sRGB and contain three (identical) channels.
-
-### Output options
-
-#### jpeg()
-
-Use JPEG format for the output image.
-
-#### png()
-
-Use PNG format for the output image.
-
-#### webp()
-
-Use WebP format for the output image.
-
-#### raw()
-
-_Requires libvips 7.42.0+_
-
-Provide raw, uncompressed uint8 (unsigned char) image data for Buffer and Stream based output.
-
-The number of channels depends on the input image and selected options.
-
-* 1 channel for images converted to `greyscale()`, with each byte representing one pixel.
-* 3 channels for colour images without alpha transparency, with bytes ordered \[red, green, blue, red, green, blue, etc.\]).
-* 4 channels for colour images with alpha transparency, with bytes ordered \[red, green, blue, alpha, red, green, blue, alpha, etc.\].
-
-#### toFormat(format)
-
-Convenience method for the above output format methods, where `format` is either:
-
-* an attribute of the `sharp.format` Object e.g. `sharp.format.jpeg`, or
-* a String containing `jpeg`, `png`, `webp` or `raw`.
-
-#### quality(quality)
-
-The output quality to use for lossy JPEG, WebP and TIFF output formats. The default quality is `80`.
-
-`quality` is a Number between 1 and 100.
-
-#### progressive()
-
-Use progressive (interlace) scan for JPEG and PNG output. This typically reduces compression performance by 30% but results in an image that can be rendered sooner when decompressed.
-
-#### withMetadata()
-
-Include all metadata (EXIF, XMP, IPTC) from the input image in the output image. This will also convert to and add the latest web-friendly v2 sRGB ICC profile.
-
-The default behaviour is to strip all metadata and convert to the device-independent sRGB colour space.
-
-#### withoutChromaSubsampling()
-
-Disable the use of [chroma subsampling](http://en.wikipedia.org/wiki/Chroma_subsampling) with JPEG output (4:4:4).
-
-This can improve colour representation at higher quality settings (90+),
-but usually increases output file size and typically reduces performance by 25%.
-
-The default behaviour is to use chroma subsampling (4:2:0).
-
-#### compressionLevel(compressionLevel)
-
-An advanced setting for the _zlib_ compression level of the lossless PNG output format. The default level is `6`.
-
-`compressionLevel` is a Number between 0 and 9.
-
-#### withoutAdaptiveFiltering()
-
-_Requires libvips 7.42.0+_
-
-An advanced setting to disable adaptive row filtering for the lossless PNG output format.
-
-### Output methods
-
-#### toFile(filename, [callback])
-
-`filename` is a String containing the filename to write the image data to. The format is inferred from the extension, with JPEG, PNG, WebP and TIFF supported.
-
-`callback`, if present, is called with two arguments `(err, info)` where:
-
-* `err` contains an error message, if any.
-* `info` contains the output image `format`, `size` (bytes), `width` and `height`.
-
-A Promises/A+ promise is returned when `callback` is not provided.
-
-#### toBuffer([callback])
-
-Write image data to a Buffer, the format of which will match the input image by default. JPEG, PNG and WebP are supported.
-
-`callback`, if present, gets three arguments `(err, buffer, info)` where:
-
-* `err` is an error message, if any.
-* `buffer` is the output image data.
-* `info` contains the output image `format`, `size` (bytes), `width` and `height`.
-
-A Promises/A+ promise is returned when `callback` is not provided.
-
-### Utility methods
-
-#### sharp.cache([memory], [items])
-
-If `memory` or `items` are provided, set the limits of _libvips'_ operation cache.
-
-* `memory` is the maximum memory in MB to use for this cache, with a default value of 100
-* `items` is the maximum number of operations to cache, with a default value of 500
-
-This method always returns cache statistics, useful for determining how much working memory is required for a particular task.
-
-```javascript
-var stats = sharp.cache(); // { current: 75, high: 99, memory: 100, items: 500 }
-sharp.cache(200); // { current: 75, high: 99, memory: 200, items: 500 }
-sharp.cache(50, 200); // { current: 49, high: 99, memory: 50, items: 200}
-```
-
-#### sharp.concurrency([threads])
-
-`threads`, if provided, is the Number of threads _libvips'_ should create for processing each image. The default value is the number of CPU cores. A value of `0` will reset to this default.
-
-This method always returns the current concurrency.
-
-```javascript
-var threads = sharp.concurrency(); // 4
-sharp.concurrency(2); // 2
-sharp.concurrency(0); // 4
-```
-
-The maximum number of images that can be processed in parallel is limited by libuv's `UV_THREADPOOL_SIZE` environment variable.
-
-#### sharp.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.
-
-```javascript
-var counters = sharp.counters(); // { queue: 2, process: 4 }
-```
-
-## Contributing
-
-A [guide for contributors](https://github.com/lovell/sharp/blob/master/CONTRIBUTING.md) covers reporting bugs, requesting features and submitting code changes.
-
-## Testing
-
-### Functional tests
-
-#### Coverage
+The typical use case for this high speed Node.js module
+is to convert large images of many formats to
+smaller, web-friendly JPEG, PNG and WebP images of varying dimensions.
 
 [![Test Coverage](https://coveralls.io/repos/lovell/sharp/badge.png?branch=master)](https://coveralls.io/r/lovell/sharp?branch=master)
 
-#### Ubuntu 12.04
+### Documentation
 
-[![Ubuntu 12.04 Build Status](https://travis-ci.org/lovell/sharp.png?branch=master)](https://travis-ci.org/lovell/sharp)
+Visit [sharp.dimens.io](http://sharp.dimens.io/) for
+complete installation instructions, API documentation,
+benchmark tests and a changelog.
 
-#### Centos 6.5
+### Contributing
 
-[![Centos 6.5 Build Status](https://snap-ci.com/lovell/sharp/branch/master/build_image)](https://snap-ci.com/lovell/sharp/branch/master)
+A [guide for contributors](https://github.com/lovell/sharp/blob/master/CONTRIBUTING.md)
+covers reporting bugs, requesting features and submitting code changes.
 
-### Benchmark tests
-
-```
-cd sharp/test/bench
-npm install
-npm test
-```
-
-Requires both _ImageMagick_ and _GraphicsMagick_:
-
-```
-brew install imagemagick
-brew install graphicsmagick
-```
-
-```
-sudo apt-get install -qq imagemagick graphicsmagick libmagickcore-dev
-```
-
-```
-sudo yum install ImageMagick
-sudo yum install -y http://download.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
-sudo yum install -y --enablerepo=epel GraphicsMagick
-```
-
-## Performance
-
-### Test environment
-
-* AWS EC2 [c3.xlarge](http://aws.amazon.com/ec2/instance-types/#Compute_Optimized)
-* Ubuntu 14.04
-* libvips 7.40.8
-* liborc 0.4.22
-
-### The contenders
-
-* [imagemagick-native](https://github.com/mash/node-imagemagick-native) v1.2.2 - Supports Buffers only
-* [imagemagick](https://github.com/yourdeveloper/node-imagemagick) v0.1.3 - Supports filesystem only and "has been unmaintained for a long time".
-* [gm](https://github.com/aheckmann/gm) v1.16.0 - Fully featured wrapper around GraphicsMagick.
-* sharp v0.6.2 - Caching within libvips disabled to ensure a fair comparison.
-
-### The task
-
-Decompress a 2725x2225 JPEG image, resize and crop to 720x480, then compress to JPEG.
-
-### Results
-
-| Module                | Input  | Output | Ops/sec | Speed-up |
-| :-------------------- | :----- | :----- | ------: | -------: |
-| imagemagick-native    | buffer | buffer |    1.58 |        1 |
-| imagemagick           | file   | file   |    6.23 |      3.9 |
-| gm                    | buffer | file   |    5.32 |      3.4 |
-| gm                    | buffer | buffer |    5.32 |      3.4 |
-| gm                    | file   | file   |    5.36 |      3.4 |
-| gm                    | file   | buffer |    5.36 |      3.4 |
-| sharp                 | buffer | file   |   22.05 |     14.0 |
-| sharp                 | buffer | buffer |   22.14 |     14.0 |
-| sharp                 | file   | file   |   21.79 |     13.8 |
-| sharp                 | file   | buffer |   21.90 |     13.9 |
-| sharp                 | stream | stream |   20.87 |     13.2 |
-| sharp +promise        | file   | buffer |   21.89 |     13.9 |
-| sharp +sharpen        | file   | buffer |   19.69 |     12.5 |
-| sharp +progressive    | file   | buffer |   16.93 |     10.7 |
-| sharp +sequentialRead | file   | buffer |   21.60 |     13.7 |
-
-You can expect greater performance with caching enabled (default) and using 8+ core machines.
-
-## Thanks
-
-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)
-
-Thank you!
-
-## Licence
+### Licence
 
 Copyright 2013, 2014, 2015 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)
+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,

appveyor.yml

@@ -0,0 +1,28 @@
+os: Visual Studio 2015
+version: "{build}"
+build: off
+platform: x64
+environment:
+  VIPS_VERSION_MAJOR_MINOR: 8.0
+  VIPS_VERSION_PATCH: 2
+  VIPS_WARNING: 0
+  matrix:
+  - nodejs_version: "0.10"
+    nodejs_exec: "node"
+  - nodejs_version: "0.12"
+    nodejs_exec: "node"
+  - nodejs_version: "2"
+    nodejs_exec: "iojs"
+  - nodejs_version: "3"
+    nodejs_exec: "iojs"
+install:
+  - ps: $env:VIPS_VERSION = "$env:VIPS_VERSION_MAJOR_MINOR.$env:VIPS_VERSION_PATCH"
+  - ps: Write-Output "Fetching http://www.vips.ecs.soton.ac.uk/supported/$env:VIPS_VERSION_MAJOR_MINOR/win32/vips-dev-$env:VIPS_VERSION.zip"
+  - ps: Start-FileDownload http://www.vips.ecs.soton.ac.uk/supported/$env:VIPS_VERSION_MAJOR_MINOR/win32/vips-dev-$env:VIPS_VERSION.zip -FileName c:\vips-dev-$env:VIPS_VERSION.zip
+  - ps: Invoke-Expression "& 7z -y x c:\vips-dev-$env:VIPS_VERSION.zip -oc:\ | FIND /V `"ing  `""
+  - ps: $env:VIPS_HOME = "c:\vips-dev-$env:VIPS_VERSION"
+  - ps: $env:PATH = "$env:VIPS_HOME\bin;$env:PATH"
+  - ps: Install-Product node $env:nodejs_version x86
+  - npm install --arch=ia32 --msvs_version=2013
+test_script:
+  - npm run-script test-win32-%nodejs_exec%

binding.gyp

@@ -3,20 +3,56 @@
     'target_name': 'sharp',
     'sources': [
       'src/common.cc',
-      'src/utilities.cc',
       'src/metadata.cc',
-      'src/resize.cc',
-      'src/sharp.cc'
+      'src/operations.cc',
+      'src/pipeline.cc',
+      'src/sharp.cc',
+      'src/utilities.cc'
     ],
-    'variables': {
-      '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'
-    },
-    'libraries': [
-      '<!(PKG_CONFIG_PATH="<(PKG_CONFIG_PATH)" pkg-config --libs vips)'
-    ],
-    'include_dirs': [
-      '<!(PKG_CONFIG_PATH="<(PKG_CONFIG_PATH)" pkg-config --cflags vips glib-2.0)',
-      '<!(node -e "require(\'nan\')")'
+    'conditions': [
+        ['OS=="win"', {
+            'library_dirs': [
+                '$(VIPS_HOME)/lib'
+            ],
+            'libraries': [
+                'libvips.dll.a',
+                'glib-2.0.lib',
+                'gobject-2.0.lib',
+                'gthread-2.0.lib',
+                'gmodule-2.0.lib',
+                'liblcms2.dll.a',
+                'libxml2.lib',
+                'intl.lib',
+                'libjpeg.dll.a',
+                'libexif.dll.a',
+                'libpng.lib',
+                'libtiff.dll.a',
+                'libMagickWand-6.Q16.dll.a',
+                'libMagickCore-6.Q16.dll.a',
+                'pango-1.0.lib',
+                'pangoft2-1.0.lib',
+                'libgsf-1.dll.a',
+                'libopenslide.dll.a',
+                'libfftw3.dll.a'
+            ],
+            'include_dirs': [
+                '$(VIPS_HOME)/include',
+                '$(VIPS_HOME)/include/glib-2.0',
+                '$(VIPS_HOME)/lib/glib-2.0/include',
+                '<!(node -e "require(\'nan\')")'
+            ]
+        }, {
+            'variables': {
+                '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'
+            },
+            'libraries': [
+                '<!(PKG_CONFIG_PATH="<(PKG_CONFIG_PATH)" pkg-config --libs vips)'
+            ],
+            'include_dirs': [
+                '<!(PKG_CONFIG_PATH="<(PKG_CONFIG_PATH)" pkg-config --cflags vips glib-2.0)',
+                '<!(node -e "require(\'nan\')")'
+            ]
+        }]
     ],
     'cflags_cc': [
       '-std=c++0x',
@@ -33,6 +69,20 @@
         '-O3'
       ],
       'MACOSX_DEPLOYMENT_TARGET': '10.7'
-    }
+    },
+    'msvs_settings': {
+      'VCCLCompilerTool': {
+        'ExceptionHandling': 1 # /EHsc
+      }
+    },
+    'configurations': {
+      'Release': {
+        'msvs_settings': {
+          'VCCLCompilerTool': {
+            'ExceptionHandling': 1,
+          }
+        }
+      }
+    },
   }]
 }

docs/api.md

@@ -0,0 +1,597 @@
+# API
+
+```javascript
+var sharp = require('sharp');
+```
+
+### Input
+
+#### sharp([input])
+
+Constructor to which further methods are chained. `input`, if present, can be one of:
+
+* Buffer containing JPEG, PNG, WebP, GIF* or TIFF image data, or
+* String containing the filename of an image, with most major formats supported.
+
+The object returned implements the
+[stream.Duplex](http://nodejs.org/api/stream.html#stream_class_stream_duplex) class.
+
+JPEG, PNG, WebP, GIF* or TIFF format image data
+can be streamed into the object when `input` is not provided.
+
+JPEG, PNG or WebP format image data can be streamed out from this object.
+
+\* libvips 8.0.0+ is required for Buffer/Stream input of GIF and other `magick` formats.
+
+```javascript
+sharp('input.jpg')
+  .resize(300, 200)
+  .toFile('output.jpg', function(err) {
+    // output.jpg is a 300 pixels wide and 200 pixels high image
+    // containing a scaled and cropped version of input.jpg
+  });
+```
+
+#### metadata([callback])
+
+Fast access to image metadata without decoding any compressed image data.
+
+`callback`, if present, gets the arguments `(err, metadata)` where `metadata` has the attributes:
+
+* `format`: Name of decoder to be used to decompress image data e.g. `jpeg`, `png`, `webp` (for file-based input additionally `tiff`, `magick` and `openslide`)
+* `width`: Number of pixels wide
+* `height`: Number of pixels high
+* `space`: Name of colour space interpretation e.g. `srgb`, `rgb`, `scrgb`, `cmyk`, `lab`, `xyz`, `b-w` [...](https://github.com/jcupitt/libvips/blob/master/libvips/iofuncs/enumtypes.c#L522)
+* `channels`: Number of bands e.g. `3` for sRGB, `4` for CMYK
+* `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
+
+A Promises/A+ promise is returned when `callback` is not provided.
+
+```javascript
+var image = sharp(inputJpg);
+image
+  .metadata()
+  .then(function(metadata) {
+    return image
+      .resize(Math.round(metadata.width / 2))
+      .webp()
+      .toBuffer();
+  })
+  .then(function(data) {
+    // data contains a WebP image half the width and height of the original JPEG
+  });
+```
+
+#### clone()
+
+Takes a "snapshot" of the 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.
+
+```javascript
+var pipeline = sharp().rotate();
+pipeline.clone().resize(800, 600).pipe(firstWritableStream);
+pipeline.clone().extract(20, 20, 100, 100).pipe(secondWritableStream);
+readableStream.pipe(pipeline);
+// firstWritableStream receives auto-rotated, resized readableStream
+// secondWritableStream receives auto-rotated, extracted region of readableStream
+```
+
+#### 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.
+
+#### limitInputPixels(pixels)
+
+Do not process input images where the number of pixels (width * height) exceeds this limit.
+
+`pixels` is the integral Number of pixels, with a value between 1 and the default 268402689 (0x3FFF * 0x3FFF).
+
+### Resizing
+
+#### resize([width], [height])
+
+Scale output to `width` x `height`. By default, the resized image is cropped to the exact size specified.
+
+`width` is the integral Number of pixels wide the resultant image should be, between 1 and 16383 (0x3FFF). Use `null` or `undefined` to auto-scale the width to match the height.
+
+`height` is the integral Number of pixels high the resultant image should be, between 1 and 16383. Use `null` or `undefined` to auto-scale the height to match the width.
+
+#### crop([gravity])
+
+Crop the resized image to the exact size specified, the default behaviour.
+
+`gravity`, if present, is a String or an attribute of the `sharp.gravity` Object e.g. `sharp.gravity.north`.
+
+Possible values are `north`, `east`, `south`, `west`, `center` and `centre`. The default gravity is `center`/`centre`.
+
+```javascript
+var transformer = sharp()
+  .resize(300, 200)
+  .crop(sharp.gravity.north)
+  .on('error', function(err) {
+    console.log(err);
+  });
+// Read image data from readableStream, resize and write image data to writableStream
+readableStream.pipe(transformer).pipe(writableStream);
+```
+
+#### 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.
+
+```javascript
+sharp('input.gif')
+  .resize(200, 300)
+  .background({r: 0, g: 0, b: 0, a: 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
+  });
+```
+
+#### 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`.
+
+```javascript
+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
+  });
+```
+
+#### 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`.
+
+#### withoutEnlargement()
+
+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*".
+
+#### ignoreAspectRatio()
+
+Ignoring the aspect ratio of the input, stretch the image to the exact `width` and/or `height` provided via `resize`.
+
+#### interpolateWith(interpolator)
+
+Use the given interpolator for image resizing, where `interpolator` is an attribute of the `sharp.interpolator` Object e.g. `sharp.interpolator.bicubic`.
+
+Possible interpolators, in order of performance, are:
+
+* `nearest`: Use [nearest neighbour interpolation](http://en.wikipedia.org/wiki/Nearest-neighbor_interpolation), suitable for image enlargement only.
+* `bilinear`: Use [bilinear interpolation](http://en.wikipedia.org/wiki/Bilinear_interpolation), the default and fastest image reduction interpolation.
+* `bicubic`: Use [bicubic interpolation](http://en.wikipedia.org/wiki/Bicubic_interpolation), which typically reduces performance by 5%.
+* `vertexSplitQuadraticBasisSpline`: Use [VSQBS interpolation](https://github.com/jcupitt/libvips/blob/master/libvips/resample/vsqbs.cpp#L48), which prevents "staircasing" and typically reduces performance by 5%.
+* `locallyBoundedBicubic`: Use [LBB interpolation](https://github.com/jcupitt/libvips/blob/master/libvips/resample/lbb.cpp#L100), which prevents some "[acutance](http://en.wikipedia.org/wiki/Acutance)" and typically reduces performance by a factor of 2.
+* `nohalo`: Use [Nohalo interpolation](http://eprints.soton.ac.uk/268086/), which prevents acutance and typically reduces performance by a factor of 3.
+
+```javascript
+sharp(inputBuffer)
+  .resize(200, 300)
+  .interpolateWith(sharp.interpolator.nohalo)
+  .background('white')
+  .embed()
+  .toFile('output.tiff')
+  .then(function() {
+    // output.tiff is a 200 pixels wide and 300 pixels high image
+    // containing a nohalo scaled version, embedded on a white canvas,
+    // of the image data in inputBuffer
+  });
+```
+
+### Operations
+
+#### extract(top, left, width, height)
+
+Extract a region of the image. Can be used with or without a `resize` operation.
+
+`top` and `left` are the offset, in pixels, from the top-left corner.
+
+`width` and `height` are the dimensions of the extracted image.
+
+Use `extract` before `resize` for pre-resize extraction. Use `extract` after `resize` for post-resize extraction. Use `extract` before and after for both.
+
+```javascript
+sharp(input)
+  .extract(top, left, width, height)
+  .toFile(output, function(err) {
+    // Extract a region of the input image, saving in the same format.
+  });
+```
+
+```javascript
+sharp(input)
+  .extract(topOffsetPre, leftOffsetPre, widthPre, heightPre)
+  .resize(width, height)
+  .extract(topOffsetPost, leftOffsetPost, widthPost, heightPost)
+  .toFile(output, function(err) {
+    // Extract a region, resize, then extract from the resized image
+  });
+```
+
+#### background(rgba)
+
+Set the background for the `embed` and `flatten` operations.
+
+`rgba` is parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
+
+The alpha value is a float between `0` (transparent) and `1` (opaque).
+
+The default background is `{r: 0, g: 0, b: 0, a: 1}`, black without transparency.
+
+#### flatten()
+
+Merge alpha transparency channel, if any, with `background`.
+
+#### rotate([angle])
+
+Rotate the output image by either an explicit angle or auto-orient based on the EXIF `Orientation` tag.
+
+`angle`, if present, is a Number with a value of `0`, `90`, `180` or `270`.
+
+Use this method without `angle` to determine the angle from EXIF data. Mirroring is supported and may infer the use of a `flip` operation.
+
+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)`.
+
+The use of `rotate` implies the removal of the EXIF `Orientation` tag, if any.
+
+```javascript
+var pipeline = sharp()
+  .rotate()
+  .resize(null, 200)
+  .progressive()
+  .toBuffer(function(err, outputBuffer, info) {
+    if (err) {
+      throw err;
+    }
+    // outputBuffer contains 200px high progressive JPEG image data,
+    // auto-rotated using EXIF Orientation tag
+    // info.width and info.height contain the dimensions of the resized image
+  });
+readableStream.pipe(pipeline);
+```
+
+#### flip()
+
+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.
+
+#### flop()
+
+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.
+
+#### blur([sigma])
+
+When used without parameters, performs a fast, mild blur of the output image. This typically reduces performance by 10%.
+
+When a `sigma` is provided, performs a slower, more accurate Gaussian blur. This typically reduces performance by 25%.
+
+* `sigma`, if present, is a Number between 0.3 and 1000 representing the approximate blur radius in pixels.
+
+#### sharpen([radius], [flat], [jagged])
+
+When used without parameters, performs a fast, mild sharpen of the output image. This typically reduces performance by 10%.
+
+When a `radius` 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. This typically reduces performance by 50%.
+
+* `radius`, if present, is an integral Number representing the sharpen mask radius in pixels.
+* `flat`, if present, is a Number representing the level of sharpening to apply to "flat" areas, defaulting to a value of 1.0.
+* `jagged`, if present, is a Number representing the level of sharpening to apply to "jagged" areas, defaulting to a value of 2.0.
+
+#### gamma([gamma])
+
+Apply a gamma correction by reducing the encoding (darken) pre-resize at a factor of `1/gamma` then increasing the encoding (brighten) post-resize at a factor of `gamma`.
+
+`gamma`, if present, is a Number betweem 1 and 3. The default value is `2.2`, a suitable approximation for sRGB images.
+
+This can improve the perceived brightness of a resized image in non-linear colour spaces.
+
+JPEG input images will not take advantage of the shrink-on-load performance optimisation when applying a gamma correction.
+
+#### grayscale() / greyscale()
+
+Convert to 8-bit greyscale; 256 shades of grey.
+
+This is a linear operation. If the input image is in a non-linear colour space such as sRGB, use `gamma()` with `greyscale()` for the best results.
+
+The output image will still be web-friendly sRGB and contain three (identical) channels.
+
+#### normalize() / normalise()
+
+Enhance output image contrast by stretching its luminance to cover the full dynamic range. This typically reduces performance by 30%.
+
+#### overlayWith(filename)
+
+_Experimental_
+
+Alpha composite `filename` over the processed (resized, extracted) image. The dimensions of the two images must match.
+
+* `filename` is a String containing the filename of an image with an alpha channel.
+
+```javascript
+sharp('input.png')
+  .rotate(180)
+  .resize(300)
+  .flatten()
+  .background('#ff6600')
+  .overlayWith('overlay.png')
+  .sharpen()
+  .withMetadata()
+  .quality(90)
+  .webp()
+  .toBuffer()
+  .then(function(outputBuffer) {
+    // outputBuffer contains upside down, 300px wide, alpha channel flattened
+    // onto orange background, composited with overlay.png, sharpened,
+    // with metadata, 90% quality WebP image data. Phew!
+  });
+```
+
+### Output
+
+#### toFile(filename, [callback])
+
+`filename` is a String containing the filename to write the image data to. The format is inferred from the extension, with JPEG, PNG, WebP, TIFF and DZI supported.
+
+`callback`, if present, is called with two arguments `(err, info)` where:
+
+* `err` contains an error message, if any.
+* `info` contains the output image `format`, `size` (bytes), `width` and `height`.
+
+A Promises/A+ promise is returned when `callback` is not provided.
+
+#### toBuffer([callback])
+
+Write image data to a Buffer, the format of which will match the input image by default. JPEG, PNG and WebP are supported.
+
+`callback`, if present, gets three arguments `(err, buffer, info)` where:
+
+* `err` is an error message, if any.
+* `buffer` is the output image data.
+* `info` contains the output image `format`, `size` (bytes), `width` and `height`.
+
+A Promises/A+ promise is returned when `callback` is not provided.
+
+#### jpeg()
+
+Use JPEG format for the output image.
+
+#### png()
+
+Use PNG format for the output image.
+
+#### webp()
+
+Use WebP format for the output image.
+
+#### raw()
+
+_Requires libvips 7.42.0+_
+
+Provide raw, uncompressed uint8 (unsigned char) image data for Buffer and Stream based output.
+
+The number of channels depends on the input image and selected options.
+
+* 1 channel for images converted to `greyscale()`, with each byte representing one pixel.
+* 3 channels for colour images without alpha transparency, with bytes ordered \[red, green, blue, red, green, blue, etc.\]).
+* 4 channels for colour images with alpha transparency, with bytes ordered \[red, green, blue, alpha, red, green, blue, alpha, etc.\].
+
+#### toFormat(format)
+
+Convenience method for the above output format methods, where `format` is either:
+
+* an attribute of the `sharp.format` Object e.g. `sharp.format.jpeg`, or
+* a String containing `jpeg`, `png`, `webp` or `raw`.
+
+#### quality(quality)
+
+The output quality to use for lossy JPEG, WebP and TIFF output formats. The default quality is `80`.
+
+`quality` is a Number between 1 and 100.
+
+#### progressive()
+
+Use progressive (interlace) scan for JPEG and PNG output. This typically reduces compression performance by 30% but results in an image that can be rendered sooner when decompressed.
+
+#### withMetadata([metadata])
+
+Include all metadata (EXIF, XMP, IPTC) from the input image in the output image.
+This will also convert to and add the latest web-friendly v2 sRGB ICC profile.
+
+The optional `metadata` parameter, if present, is an Object with the attributes to update.
+New attributes cannot be inserted, only existing attributes updated.
+
+* `orientation` is an integral Number between 0 and 7, used to update the value of the EXIF `Orientation` tag.
+This has no effect if the input image does not have an EXIF `Orientation` tag.
+
+The default behaviour, when `withMetadata` is not used, is to strip all metadata and convert to the device-independent sRGB colour space.
+
+#### tile([size], [overlap])
+
+The size and overlap, in pixels, of square Deep Zoom image pyramid tiles.
+
+* `size` is an integral Number between 1 and 8192. The default value is 256 pixels.
+* `overlap` is an integral Number between 0 and 8192. The default value is 0 pixels.
+
+```javascript
+sharp('input.tiff').tile(256).toFile('output.dzi', function(err, info) {
+  // The output.dzi file is the XML format Deep Zoom definition
+  // The output_files directory contains 256x256 pixel tiles grouped by zoom level
+});
+```
+
+#### withoutChromaSubsampling()
+
+Disable the use of [chroma subsampling](http://en.wikipedia.org/wiki/Chroma_subsampling) with JPEG output (4:4:4).
+
+This can improve colour representation at higher quality settings (90+),
+but usually increases output file size and typically reduces performance by 25%.
+
+The default behaviour is to use chroma subsampling (4:2:0).
+
+#### compressionLevel(compressionLevel)
+
+An advanced setting for the _zlib_ compression level of the lossless PNG output format. The default level is `6`.
+
+`compressionLevel` is a Number between 0 and 9.
+
+#### withoutAdaptiveFiltering()
+
+_Requires libvips 7.42.0+_
+
+An advanced setting to disable adaptive row filtering for the lossless PNG output format.
+
+#### trellisQuantisation() / trellisQuantization()
+
+_Requires libvips 8.0.0+ compiled against mozjpeg 3.0+_
+
+An advanced setting to apply the use of
+[trellis quantisation](http://en.wikipedia.org/wiki/Trellis_quantization) with JPEG output.
+Reduces file size and slightly increases relative quality at the cost of increased compression time.
+
+#### overshootDeringing()
+
+_Requires libvips 8.0.0+ compiled against mozjpeg 3.0+_
+
+An advanced setting to reduce the effects of
+[ringing](http://en.wikipedia.org/wiki/Ringing_%28signal%29) in JPEG output,
+in particular where black text appears on a white background (or vice versa).
+
+#### optimiseScans() / optimizeScans()
+
+_Requires libvips 8.0.0+ compiled against mozjpeg 3.0+_
+
+An advanced setting for progressive (interlace) JPEG output.
+Calculates which spectrum of DCT coefficients uses the fewest bits.
+Usually reduces file size at the cost of increased compression time.
+
+### Attributes
+
+#### format
+
+An Object containing nested boolean values
+representing the available input and output formats/methods,
+for example:
+
+```javascript
+> console.dir(sharp.format);
+
+{ jpeg: { id: 'jpeg',
+    input: { file: true, buffer: true, stream: true },
+    output: { file: true, buffer: true, stream: true } },
+  png: { id: 'png',
+    input: { file: true, buffer: true, stream: true },
+    output: { file: true, buffer: true, stream: true } },
+  webp: { id: 'webp',
+    input: { file: true, buffer: true, stream: true },
+    output: { file: true, buffer: true, stream: true } },
+  tiff: { id: 'tiff',
+    input: { file: true, buffer: true, stream: true },
+    output: { file: true, buffer: false, stream: false } },
+  magick: { id: 'magick',
+    input: { file: true, buffer: true, stream: true },
+    output: { file: false, buffer: false, stream: false } },
+  raw: { id: 'raw',
+    input: { file: false, buffer: false, stream: false },
+    output: { file: false, buffer: true, stream: true } } }
+```
+
+#### queue
+
+An EventEmitter that emits a `change` event when a task is either:
+
+* queued, waiting for _libuv_ to provide a worker thread
+* complete
+
+```javascript
+sharp.queue.on('change', function(queueLength) {
+  console.log('Queue contains ' + queueLength + ' task(s)');
+});
+```
+
+### Utilities
+
+#### sharp.cache([memory], [items])
+
+If `memory` or `items` are provided, set the limits of _libvips'_ operation cache.
+
+* `memory` is the maximum memory in MB to use for this cache, with a default value of 100
+* `items` is the maximum number of operations to cache, with a default value of 500
+
+This method always returns cache statistics, useful for determining how much working memory is required for a particular task.
+
+```javascript
+var stats = sharp.cache(); // { current: 75, high: 99, memory: 100, items: 500 }
+sharp.cache(200); // { current: 75, high: 99, memory: 200, items: 500 }
+sharp.cache(50, 200); // { current: 49, high: 99, memory: 50, items: 200}
+```
+
+#### sharp.concurrency([threads])
+
+`threads`, if provided, is the Number of threads _libvips'_ should create for processing each image. The default value is the number of CPU cores. A value of `0` will reset to this default.
+
+This method always returns the current concurrency.
+
+```javascript
+var threads = sharp.concurrency(); // 4
+sharp.concurrency(2); // 2
+sharp.concurrency(0); // 4
+```
+
+The maximum number of images that can be processed in parallel is limited by libuv's `UV_THREADPOOL_SIZE` environment variable.
+
+#### sharp.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.
+
+```javascript
+var counters = sharp.counters(); // { queue: 2, process: 4 }
+```

docs/changelog.md

@@ -0,0 +1,87 @@
+# Changelog
+
+### v0.11 - "*knife*"
+
+#### v0.11.3 - 8<sup>th</sup> September 2015
+
+* Intrepret blurSigma, sharpenFlat, and sharpenJagged as double precision.
+  [#263](https://github.com/lovell/sharp/pull/263)
+  [@chrisriley](https://github.com/chrisriley)
+
+#### v0.11.2 - 28<sup>th</sup> August 2015
+
+* Allow crop gravity to be provided as a String.
+  [#255](https://github.com/lovell/sharp/pull/255)
+  [@papandreou](https://github.com/papandreou)
+* Add support for io.js v3 and Node v4.
+  [#246](https://github.com/lovell/sharp/issues/246)
+
+#### v0.11.1 - 12<sup>th</sup> August 2015
+
+* Silence MSVC warning: "C4530: C++ exception handler used, but unwind semantics are not enabled".
+  [#244](https://github.com/lovell/sharp/pull/244)
+  [@TheThing](https://github.com/TheThing)
+
+* Suppress gamma correction for input image with alpha transparency.
+  [#249](https://github.com/lovell/sharp/issues/249)
+  [@compeak](https://github.com/compeak)
+
+#### v0.11.0 - 15<sup>th</sup> July 2015
+
+* Allow alpha transparency compositing via new `overlayWith` method.
+  [#97](https://github.com/lovell/sharp/issues/97)
+  [@gasi](https://github.com/gasi)
+
+* Expose raw ICC profile data as a Buffer when using `metadata`.
+  [#129](https://github.com/lovell/sharp/issues/129)
+  [@homerjam](https://github.com/homerjam)
+
+* Allow image header updates via a parameter passed to existing `withMetadata` method.
+  Provide initial support for EXIF `Orientation` tag,
+  which if present is now removed when using `rotate`, `flip` or `flop`.
+  [#189](https://github.com/lovell/sharp/issues/189)
+  [@h2non](https://github.com/h2non)
+
+* Tighten constructor parameter checks.
+  [#221](https://github.com/lovell/sharp/issues/221)
+  [@mikemorris](https://github.com/mikemorris)
+
+* Allow one input Stream to be shared with two or more output Streams via new `clone` method.
+  [#235](https://github.com/lovell/sharp/issues/235)
+  [@jaubourg](https://github.com/jaubourg)
+
+* Use `round` instead of `floor` when auto-scaling dimensions to avoid floating-point rounding errors.
+  [#238](https://github.com/lovell/sharp/issues/238)
+  [@richardadjogah](https://github.com/richardadjogah)
+
+### v0.10 - "*judgment*"
+
+#### v0.10.1 - 1<sup>st</sup> June 2015
+
+* Allow embed of image with alpha transparency onto non-transparent background.
+  [#204](https://github.com/lovell/sharp/issues/204)
+  [@mikemliu](https://github.com/mikemliu)
+
+* Include C standard library for `atoi` as Xcode 6.3 appears to no longer do this.
+  [#228](https://github.com/lovell/sharp/issues/228)
+  [@doggan](https://github.com/doggan)
+
+#### v0.10.0 - 23<sup>rd</sup> April 2015
+
+* Add support for Windows (x86).
+  [#19](https://github.com/lovell/sharp/issues/19)
+  [@DullReferenceException](https://github.com/DullReferenceException)
+  [@itsananderson](https://github.com/itsananderson)
+
+* Add support for Openslide input and DeepZoom output.
+  [#146](https://github.com/lovell/sharp/issues/146)
+  [@mvictoras](https://github.com/mvictoras)
+
+* Allow arbitrary aspect ratios when resizing images via new `ignoreAspectRatio` method.
+  [#192](https://github.com/lovell/sharp/issues/192)
+  [@skedastik](https://github.com/skedastik)
+
+* Enhance output image contrast by stretching its luminance to cover the full dynamic range via new `normalize` method.
+  [#194](https://github.com/lovell/sharp/issues/194)
+  [@bkw](https://github.com/bkw)
+  [@codingforce](https://github.com/codingforce)

docs/index.md

@@ -0,0 +1,103 @@
+# sharp
+
+The typical use case for this high speed Node.js module
+is to convert large images of many formats to
+smaller, web-friendly JPEG, PNG and WebP images of varying dimensions.
+
+Resizing an image is typically 4x faster than using
+the quickest ImageMagick and GraphicsMagick settings.
+
+[![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, OpenSlide,
+GIF and other libmagick-supported formats.
+
+Output images can be in JPEG, PNG and WebP 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).
+
+### Features
+
+As well as image resizing, operations such as
+rotation, extraction, compositing and gamma correction are available.
+
+Colour spaces, embedded ICC profiles and alpha transparency channels
+are all handled correctly.
+
+### 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 can be disabled,
+which for diagrams and line art often produces the same result
+as [pngcrush](http://pmt.sourceforge.net/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)
+
+Thank you!
+
+### Licence
+
+Copyright 2013, 2014, 2015 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

@@ -0,0 +1,123 @@
+# Installation
+
+```sh
+npm install sharp
+```
+
+### Prerequisites
+
+* Node.js v0.10+ or io.js
+* [libvips](https://github.com/jcupitt/libvips) v7.40.0+ (7.42.0+ recommended)
+* C++11 compatible compiler such as gcc 4.6+, clang 3.0+ or MSVC 2013 (io.js v3+ requires gcc 4.8+)
+
+### Linux
+
+[![Ubuntu 12.04 Build Status](https://travis-ci.org/lovell/sharp.png?branch=master)](https://travis-ci.org/lovell/sharp)
+[![Centos 6.5 Build Status](https://snap-ci.com/lovell/sharp/branch/master/build_image)](https://snap-ci.com/lovell/sharp/branch/master)
+
+For a system-wide installation of the most suitable version of
+libvips and its dependencies on the following Operating Systems:
+
+* Debian 7, 8
+* Ubuntu 12.04, 14.04, 14.10, 15.04
+* Mint 13, 17
+* RHEL/Centos/Scientific 6, 7
+* Fedora 21, 22
+* Amazon Linux 2014.09, 2015.03
+* OpenSuse 13
+
+run the following as a user with `sudo` access:
+
+```sh
+curl -s https://raw.githubusercontent.com/lovell/sharp/master/preinstall.sh | sudo bash -
+```
+
+or run the following as `root`:
+
+```sh
+curl -s https://raw.githubusercontent.com/lovell/sharp/master/preinstall.sh | bash -
+```
+
+The [preinstall.sh](https://github.com/lovell/sharp/blob/master/preinstall.sh) script requires `curl` and `pkg-config`.
+
+Add `--with-openslide` to enable OpenSlide support:
+
+```sh
+curl -s https://raw.githubusercontent.com/lovell/sharp/master/preinstall.sh | sudo bash -s -- --with-openslide
+```
+
+#### Ubuntu LTS
+
+libvips v7.40.6 is available via a PPA.
+
+##### 12.04
+
+```sh
+sudo add-apt-repository -y ppa:lovell/precise-backport-vips
+sudo apt-get update
+sudo apt-get install -y libvips-dev libgsf-1-dev
+```
+
+##### 14.04
+
+```sh
+sudo add-apt-repository -y ppa:lovell/trusty-backport-vips
+sudo apt-get update
+sudo apt-get install -y libvips-dev libgsf-1-dev
+```
+
+### Mac OS
+
+[![OS X 10.9.5 Build Status](https://travis-ci.org/lovell/sharp-osx-ci.png?branch=master)](https://travis-ci.org/lovell/sharp-osx-ci)
+
+Install libvips via homebrew:
+
+```sh
+brew install homebrew/science/vips --with-webp --with-graphicsmagick
+```
+
+A missing or incorrectly configured _Xcode Command Line Tools_ installation
+[can lead](https://github.com/lovell/sharp/issues/80) to a
+`library not found for -ljpeg` error.
+If so, please try: `xcode-select --install`.
+
+The _gettext_ dependency of _libvips_
+[can lead](https://github.com/lovell/sharp/issues/9)
+to a `library not found for -lintl` error.
+If so, please try `brew link gettext --force`.
+
+### Windows
+
+[![Windows Server 2012 Build Status](https://ci.appveyor.com/api/projects/status/pgtul704nkhhg6sg)](https://ci.appveyor.com/project/lovell/sharp)
+
+Requires x86 32-bit Node.js or io.js (use `iojs.exe` rather than `node.exe`).
+
+The WebP format is currently unsupported.
+
+1. Ensure the [node-gyp prerequisites](https://github.com/TooTallNate/node-gyp#installation) are met.
+2. [Download](http://www.vips.ecs.soton.ac.uk/supported/current/win32/) and unzip `vips-dev.x.y.z.zip`.
+3. Set the `VIPS_HOME` environment variable to the full path of the `vips-dev-x.y.z` directory.
+4. Add `vips-dev-x.y.z\bin` to `PATH`.
+
+Versions of MSVC more recent than 2013 may require the use of `npm install --arch=ia32 --msvs_version=2013`.
+
+### Heroku
+
+[Alessandro Tagliapietra](https://github.com/alex88) maintains an
+[Heroku buildpack for libvips](https://github.com/alex88/heroku-buildpack-vips)
+and its dependencies.
+
+### Docker
+
+[Marc Bachmann](https://github.com/marcbachmann) maintains a
+[Dockerfile for libvips](https://github.com/marcbachmann/dockerfile-libvips).
+
+```sh
+docker pull marcbachmann/libvips
+```
+
+### Build tools
+
+* [gulp-responsive](https://www.npmjs.com/package/gulp-responsive)
+* [gulp-sharp](https://www.npmjs.com/package/gulp-sharp)
+* [grunt-sharp](https://www.npmjs.com/package/grunt-sharp)

docs/performance.md

@@ -0,0 +1,63 @@
+# Performance
+
+### Test environment
+
+* AWS EC2 [c4.xlarge](http://aws.amazon.com/ec2/instance-types/#c4)
+* Ubuntu 15.04
+* Node.js 0.12.7
+* libvips 8.0.2
+* liborc 0.4.22
+
+### The contenders
+
+* [lwip](https://www.npmjs.com/package/lwip) 0.0.7 - Wrapper around CImg, compiles dependencies from source
+* [imagemagick-native](https://www.npmjs.com/package/imagemagick-native) git@45d4e2e - Wrapper around libmagick++, supports Buffers only.
+* [imagemagick](https://www.npmjs.com/package/imagemagick) 0.1.3 - Supports filesystem only and "*has been unmaintained for a long time*".
+* [gm](https://www.npmjs.com/package/gm) 1.18.1 - Fully featured wrapper around GraphicsMagick's `convert` command line utility.
+* sharp 0.11.0 - Caching within libvips disabled to ensure a fair comparison.
+
+### The task
+
+Decompress a 2725x2225 JPEG image, resize to 720x480 using bilinear interpolation, then compress to JPEG.
+
+### Results
+
+| Module             | Input  | Output | Ops/sec | Speed-up |
+| :----------------- | :----- | :----- | ------: | -------: |
+| lwip               | file   | file   |    1.75 |        1 |
+| lwip               | buffer | buffer |    2.21 |      1.3 |
+| imagemagick-native | buffer | buffer |    7.13 |      4.1 |
+| gm                 | buffer | buffer |    7.27 |      4.2 |
+| gm                 | file   | file   |    7.33 |      4.2 |
+| imagemagick        | file   | file   |   10.04 |      5.7 |
+| sharp              | stream | stream |   23.12 |     13.2 |
+| sharp              | file   | file   |   24.43 |     14.0 |
+| sharp              | file   | buffer |   24.55 |     14.0 |
+| sharp              | buffer | file   |   24.86 |     14.2 |
+| sharp              | buffer | buffer |   24.92 |     14.2 |
+
+Greater performance can be expected with caching enabled (default) and using 8+ core machines.
+
+The I/O limits of the relevant (de)compression library will generally determine maximum throughput.
+
+### Benchmark test prerequisites
+
+Requires both _ImageMagick_ and _GraphicsMagick_:
+
+```sh
+brew install imagemagick
+brew install graphicsmagick
+```
+
+```sh
+sudo apt-get install imagemagick graphicsmagick libmagick++-dev
+```
+
+### Running the benchmark test
+
+```sh
+git clone https://github.com/lovell/sharp.git
+cd sharp/test/bench
+npm install
+npm test
+```

index.js

@@ -3,6 +3,7 @@
 var path = require('path');
 var util = require('util');
 var stream = require('stream');
+var events = require('events');
 
 var semver = require('semver');
 var color = require('color');
@@ -41,7 +42,7 @@ var Sharp = function(input) {
     heightPost: -1,
     width: -1,
     height: -1,
-    canvas: 'c',
+    canvas: 'crop',
     gravity: 0,
     angle: 0,
     rotateBeforePreExtract: false,
@@ -58,6 +59,9 @@ var Sharp = function(input) {
     sharpenJagged: 2,
     gamma: 0,
     greyscale: false,
+    normalize: 0,
+    // overlay
+    overlayPath: '',
     // output options
     output: '__input',
     progressive: false,
@@ -65,39 +69,46 @@ var Sharp = function(input) {
     compressionLevel: 6,
     withoutAdaptiveFiltering: false,
     withoutChromaSubsampling: false,
+    trellisQuantisation: false,
+    overshootDeringing: false,
+    optimiseScans: false,
     streamOut: false,
-    withMetadata: false
+    withMetadata: false,
+    withMetadataOrientation: -1,
+    tileSize: 256,
+    tileOverlap: 0,
+    // Function to notify of queue length changes
+    queueListener: function(queueLength) {
+      module.exports.queue.emit('change', queueLength);
+    }
   };
   if (typeof input === 'string') {
     // input=file
     this.options.fileIn = input;
   } else if (typeof input === 'object' && input instanceof Buffer) {
     // input=buffer
-    if (
-      (input.length > 3) &&
-      // JPEG
-      (input[0] === 0xFF && input[1] === 0xD8) ||
-      // PNG
-      (input[0] === 0x89 && input[1] === 0x50) ||
-      // WebP
-      (input[0] === 0x52 && input[1] === 0x49) ||
-      // TIFF
-      (input[0] === 0x4D && input[1] === 0x4D && input[2] === 0x00 && (input[3] === 0x2A || input[3] === 0x2B)) ||
-      (input[0] === 0x49 && input[1] === 0x49 && (input[2] === 0x2A || input[2] === 0x2B) && input[3] === 0x00)
-    ) {
-      this.options.bufferIn = input;
-    } else {
-      throw new Error('Buffer contains an unsupported image format. JPEG, PNG, WebP and TIFF are currently supported.');
-    }
-  } else {
+    this.options.bufferIn = input;
+  } else if (typeof input === 'undefined') {
     // input=stream
     this.options.streamIn = true;
+  } else {
+    throw new Error('Unsupported input ' + typeof input);
   }
   return this;
 };
 module.exports = Sharp;
 util.inherits(Sharp, stream.Duplex);
 
+/*
+  EventEmitter singleton emits queue length 'change' events
+*/
+module.exports.queue = new events.EventEmitter();
+
+/*
+  Supported image formats
+*/
+module.exports.format = sharp.format();
+
 /*
   Handle incoming chunk on Writable Stream
 */
@@ -129,9 +140,11 @@ Sharp.prototype._write = function(chunk, encoding, callback) {
 module.exports.gravity = {'center': 0, 'centre': 0, 'north': 1, 'east': 2, 'south': 3, 'west': 4};
 
 Sharp.prototype.crop = function(gravity) {
-  this.options.canvas = 'c';
+  this.options.canvas = 'crop';
   if (typeof gravity === 'number' && !Number.isNaN(gravity) && gravity >= 0 && gravity <= 4) {
     this.options.gravity = gravity;
+  } else if (typeof gravity === 'string' && typeof module.exports.gravity[gravity] === 'number') {
+    this.options.gravity = module.exports.gravity[gravity];
   } else {
     throw new Error('Unsupported crop gravity ' + gravity);
   }
@@ -169,12 +182,26 @@ Sharp.prototype.background = function(rgba) {
 };
 
 Sharp.prototype.embed = function() {
-  this.options.canvas = 'e';
+  this.options.canvas = 'embed';
   return this;
 };
 
 Sharp.prototype.max = function() {
-  this.options.canvas = 'm';
+  this.options.canvas = 'max';
+  return this;
+};
+
+Sharp.prototype.min = function() {
+  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 the resize method.
+*/
+Sharp.prototype.ignoreAspectRatio = function() {
+  this.options.canvas = 'ignore_aspect';
   return this;
 };
 
@@ -183,6 +210,17 @@ Sharp.prototype.flatten = function(flatten) {
   return this;
 };
 
+Sharp.prototype.overlayWith = function(overlayPath) {
+  if (typeof overlayPath !== 'string') {
+    throw new Error('The overlay path must be a string');
+  }
+  if (overlayPath === '') {
+    throw new Error('The overlay path cannot be empty');
+  }
+  this.options.overlayPath = overlayPath;
+  return this;
+};
+
 /*
   Rotate output image by 0, 90, 180 or 270 degrees
   Auto-rotation based on the EXIF Orientation tag is represented by an angle of -1
@@ -297,7 +335,18 @@ module.exports.interpolator = {
   vertexSplitQuadraticBasisSpline: 'vsqbs'
 };
 Sharp.prototype.interpolateWith = function(interpolator) {
-  this.options.interpolator = interpolator;
+  var isValid = false;
+  for (var key in module.exports.interpolator) {
+    if (module.exports.interpolator[key] === interpolator) {
+      isValid = true;
+      break;
+    }
+  }
+  if (isValid) {
+    this.options.interpolator = interpolator;
+  } else {
+    throw new Error('Invalid interpolator ' + interpolator);
+  }
   return this;
 };
 
@@ -317,6 +366,19 @@ Sharp.prototype.gamma = function(gamma) {
   return this;
 };
 
+/*
+  Enhance output image contrast by stretching its luminance to cover the full dynamic range
+*/
+Sharp.prototype.normalize = function(normalize) {
+  if (process.platform !== 'win32') {
+    this.options.normalize = (typeof normalize === 'boolean') ? normalize : true;
+  } else {
+    console.error('normalize unavailable on win32 platform');
+  }
+  return this;
+};
+Sharp.prototype.normalise = Sharp.prototype.normalize;
+
 /*
   Convert to greyscale
 */
@@ -337,7 +399,7 @@ Sharp.prototype.sequentialRead = function(sequentialRead) {
 };
 
 Sharp.prototype.quality = function(quality) {
-  if (!Number.isNaN(quality) && quality >= 1 && quality <= 100) {
+  if (!Number.isNaN(quality) && quality >= 1 && quality <= 100 && quality % 1 === 0) {
     this.options.quality = quality;
   } else {
     throw new Error('Invalid quality (1 to 100) ' + quality);
@@ -377,8 +439,95 @@ Sharp.prototype.withoutChromaSubsampling = function(withoutChromaSubsampling) {
   return this;
 };
 
+/*
+  Apply trellis quantisation to JPEG output - requires libvips 8.0.0+ compiled against mozjpeg 3.0+
+*/
+Sharp.prototype.trellisQuantisation = function(trellisQuantisation) {
+  if (semver.gte(libvipsVersion, '8.0.0')) {
+    this.options.trellisQuantisation = (typeof trellisQuantisation === 'boolean') ? trellisQuantisation : true;
+  } else {
+    console.error('trellisQuantisation requires libvips 8.0.0+');
+  }
+  return this;
+};
+Sharp.prototype.trellisQuantization = Sharp.prototype.trellisQuantisation;
+
+/*
+  Apply overshoot deringing to JPEG output - requires libvips 8.0.0+ compiled against mozjpeg 3.0+
+*/
+Sharp.prototype.overshootDeringing = function(overshootDeringing) {
+  if (semver.gte(libvipsVersion, '8.0.0')) {
+    this.options.overshootDeringing = (typeof overshootDeringing === 'boolean') ? overshootDeringing : true;
+  } else {
+    console.error('overshootDeringing requires libvips 8.0.0+');
+  }
+  return this;
+};
+
+/*
+  Optimise scans in progressive JPEG output - requires libvips 8.0.0+ compiled against mozjpeg 3.0+
+*/
+Sharp.prototype.optimiseScans = function(optimiseScans) {
+  if (semver.gte(libvipsVersion, '8.0.0')) {
+    this.options.optimiseScans = (typeof optimiseScans === 'boolean') ? optimiseScans : true;
+    if (this.options.optimiseScans) {
+      this.progressive();
+    }
+  } else {
+    console.error('optimiseScans requires libvips 8.0.0+');
+  }
+  return this;
+};
+Sharp.prototype.optimizeScans = Sharp.prototype.optimiseScans;
+
+/*
+  Include all metadata (EXIF, XMP, IPTC) from the input image in the output image
+  Optionally provide an Object with attributes to update:
+    orientation: numeric value for EXIF Orientation tag
+*/
 Sharp.prototype.withMetadata = function(withMetadata) {
   this.options.withMetadata = (typeof withMetadata === 'boolean') ? withMetadata : true;
+  if (typeof withMetadata === 'object') {
+    if ('orientation' in withMetadata) {
+      if (
+        typeof withMetadata.orientation === 'number' &&
+        !Number.isNaN(withMetadata.orientation) &&
+        withMetadata.orientation % 1 === 0 &&
+        withMetadata.orientation >=0 &&
+        withMetadata.orientation <= 7
+      ) {
+        this.options.withMetadataOrientation = withMetadata.orientation;
+      } else {
+        throw new Error('Invalid orientation (0 to 7) ' + withMetadata.orientation);
+      }
+    }
+  }
+  return this;
+};
+
+/*
+  Tile size and overlap for Deep Zoom output
+*/
+Sharp.prototype.tile = function(size, overlap) {
+  // Size of square tiles, in pixels
+  if (typeof size !== 'undefined' && size !== null) {
+    if (!Number.isNaN(size) && size % 1 === 0 && size >= 1 && size <= 8192) {
+      this.options.tileSize = size;
+    } else {
+      throw new Error('Invalid tile size (1 to 8192) ' + size);
+    }
+  }
+  // Overlap of tiles, in pixels
+  if (typeof overlap !== 'undefined' && overlap !== null) {
+    if (!Number.isNaN(overlap) && overlap % 1 === 0 && overlap >=0 && overlap <= 8192) {
+      if (overlap > this.options.tileSize) {
+        throw new Error('Tile overlap ' + overlap + ' cannot be larger than tile size ' + this.options.tileSize);
+      }
+      this.options.tileOverlap = overlap;
+    } else {
+      throw new Error('Invalid tile overlap (0 to 8192) ' + overlap);
+    }
+  }
   return this;
 };
 
@@ -409,7 +558,7 @@ Sharp.prototype.resize = function(width, height) {
   Assumes the image dimensions contained in the file header can be trusted
 */
 Sharp.prototype.limitInputPixels = function(limit) {
-  if (typeof limit === 'number' && !Number.isNaN(limit) && limit % 1 === 0 && limit > 0 && limit <= maximum.pixels) {
+  if (typeof limit === 'number' && !Number.isNaN(limit) && limit % 1 === 0 && limit > 0) {
     this.options.limitInputPixels = limit;
   } else {
     throw new Error('Invalid pixel limit (1 to ' + maximum.pixels + ') ' + limit);
@@ -438,7 +587,7 @@ Sharp.prototype.toFile = function(output, callback) {
       }
     } else {
       this.options.output = output;
-      return this._sharp(callback);
+      return this._pipeline(callback);
     }
   }
   return this;
@@ -448,7 +597,7 @@ Sharp.prototype.toFile = function(output, callback) {
   Write output to a Buffer
 */
 Sharp.prototype.toBuffer = function(callback) {
-  return this._sharp(callback);
+  return this._pipeline(callback);
 };
 
 /*
@@ -479,7 +628,8 @@ Sharp.prototype.webp = function() {
   Force raw, uint8 output
 */
 Sharp.prototype.raw = function() {
-  if (semver.gte(libvipsVersion, '7.42.0')) {
+  var supportsRawOutput = module.exports.format.raw.output;
+  if (supportsRawOutput.file || supportsRawOutput.buffer || supportsRawOutput.stream) {
     this.options.output = '__raw';
   } else {
     console.error('Raw output requires libvips 7.42.0+');
@@ -489,15 +639,15 @@ Sharp.prototype.raw = function() {
 
 /*
   Force output to a given format
+  @param format is either the id as a String or an Object with an 'id' attribute
 */
-module.exports.format = {'jpeg': 'jpeg', 'png': 'png', 'webp': 'webp', 'raw': 'raw'};
 Sharp.prototype.toFormat = function(format) {
-  if (
-    typeof format === 'string' &&
-    typeof module.exports.format[format] === 'string' &&
-    typeof this[format] === 'function'
-  ) {
-    this[format]();
+  var id = format;
+  if (typeof format === 'object') {
+    id = format.id;
+  }
+  if (typeof id === 'string' && typeof module.exports.format[id] === 'object' && typeof this[id] === 'function') {
+    this[id]();
   } else {
     throw new Error('Unsupported format ' + format);
   }
@@ -510,7 +660,7 @@ Sharp.prototype.toFormat = function(format) {
 Sharp.prototype._read = function() {
   if (!this.options.streamOut) {
     this.options.streamOut = true;
-    this._sharp();
+    this._pipeline();
   }
 };
 
@@ -518,18 +668,18 @@ Sharp.prototype._read = function() {
   Invoke the C++ image processing pipeline
   Supports callback, stream and promise variants
 */
-Sharp.prototype._sharp = function(callback) {
+Sharp.prototype._pipeline = function(callback) {
   var that = this;
   if (typeof callback === 'function') {
     // output=file/buffer
     if (this.options.streamIn) {
       // output=file/buffer, input=stream
       this.on('finish', function() {
-        sharp.resize(that.options, callback);
+        sharp.pipeline(that.options, callback);
       });
     } else {
       // output=file/buffer, input=file/buffer
-      sharp.resize(this.options, callback);
+      sharp.pipeline(this.options, callback);
     }
     return this;
   } else if (this.options.streamOut) {
@@ -537,9 +687,9 @@ Sharp.prototype._sharp = function(callback) {
     if (this.options.streamIn) {
       // output=stream, input=stream
       this.on('finish', function() {
-        sharp.resize(that.options, function(err, data) {
+        sharp.pipeline(that.options, function(err, data) {
           if (err) {
-            that.emit('error', new Error(err));
+            that.emit('error', err);
           } else {
             that.push(data);
           }
@@ -548,9 +698,9 @@ Sharp.prototype._sharp = function(callback) {
       });
     } else {
       // output=stream, input=file/buffer
-      sharp.resize(this.options, function(err, data) {
+      sharp.pipeline(this.options, function(err, data) {
         if (err) {
-          that.emit('error', new Error(err));
+          that.emit('error', err);
         } else {
           that.push(data);
         }
@@ -564,7 +714,7 @@ Sharp.prototype._sharp = function(callback) {
       // output=promise, input=stream
       return new BluebirdPromise(function(resolve, reject) {
         that.on('finish', function() {
-          sharp.resize(that.options, function(err, data) {
+          sharp.pipeline(that.options, function(err, data) {
             if (err) {
               reject(err);
             } else {
@@ -576,7 +726,7 @@ Sharp.prototype._sharp = function(callback) {
     } else {
       // output=promise, input=file/buffer
       return new BluebirdPromise(function(resolve, reject) {
-        sharp.resize(that.options, function(err, data) {
+        sharp.pipeline(that.options, function(err, data) {
           if (err) {
             reject(err);
           } else {
@@ -607,22 +757,22 @@ Sharp.prototype.metadata = function(callback) {
     if (this.options.streamIn) {
       return new BluebirdPromise(function(resolve, reject) {
         that.on('finish', function() {
-          sharp.metadata(that.options, function(err, data) {
+          sharp.metadata(that.options, function(err, metadata) {
             if (err) {
               reject(err);
             } else {
-              resolve(data);
+              resolve(metadata);
             }
           });
         });
       });
     } else {
       return new BluebirdPromise(function(resolve, reject) {
-        sharp.metadata(that.options, function(err, data) {
+        sharp.metadata(that.options, function(err, metadata) {
           if (err) {
             reject(err);
           } else {
-            resolve(data);
+            resolve(metadata);
           }
         });
       });
@@ -630,6 +780,24 @@ Sharp.prototype.metadata = function(callback) {
   }
 };
 
+/*
+  Clone new instance using existing options.
+  Cloned instances share the same input.
+*/
+Sharp.prototype.clone = function() {
+  // Clone existing options
+  var clone = new Sharp();
+  util._extend(clone.options, this.options);
+  clone.streamIn = false;
+  // Pass 'finish' event to clone for Stream-based input
+  this.on('finish', function() {
+    // Clone inherits input data
+    clone.options.bufferIn = this.options.bufferIn;
+    clone.emit('finish');
+  });
+  return clone;
+};
+
 /*
   Get and set cache memory and item limits
 */

mkdocs.yml

@@ -0,0 +1,17 @@
+site_name: sharp
+site_url: http://sharp.dimens.io/
+repo_url: https://github.com/lovell/sharp
+site_description: The fastest Node.js module for resizing JPEG, PNG, WebP and TIFF images. Uses the libvips library.
+copyright: <a href="https://dimens.io/">dimens.io</a>
+google_analytics: ['UA-13034748-12', 'sharp.dimens.io']
+theme: readthedocs
+markdown_extensions:
+  - toc:
+      permalink: True
+dev_addr: 0.0.0.0:10101
+pages:
+  - Home: index.md
+  - Installation: install.md
+  - API: api.md
+  - Performance: performance.md
+  - Changelog: changelog.md

package.json

@@ -1,6 +1,6 @@
 {
   "name": "sharp",
-  "version": "0.9.2",
+  "version": "0.11.3",
   "author": "Lovell Fuller <npm@lovell.info>",
   "contributors": [
     "Pierre Inglebert <pierre.inglebert@gmail.com>",
@@ -11,11 +11,22 @@
     "Julian Walker <julian@fiftythree.com>",
     "Amit Pitaru <pitaru.amit@gmail.com>",
     "Brandon Aaron <hello.brandon@aaron.sh>",
-    "Andreas Lind <andreas@one.com>"
+    "Andreas Lind <andreas@one.com>",
+    "Maurus Cuelenaere <mcuelenaere@gmail.com>",
+    "Linus Unnebäck <linus@folkdatorn.se>",
+    "Victor Mateevitsi <mvictoras@gmail.com>",
+    "Alaric Holloway <alaric.holloway@gmail.com>",
+    "Bernhard K. Weisshuhn <bkw@codingforce.com>",
+    "Chris Riley <criley@primedia.com>"
   ],
   "description": "High performance Node.js module to resize JPEG, PNG, WebP and TIFF images using the libvips library",
   "scripts": {
-    "test": "VIPS_WARNING=0 node ./node_modules/istanbul/lib/cli.js cover ./node_modules/mocha/bin/_mocha -- --slow=5000 --timeout=10000 ./test/unit/*.js"
+    "clean": "rm -rf test/fixtures/output.*",
+    "test": "VIPS_WARNING=0 node ./node_modules/istanbul/lib/cli.js cover ./node_modules/mocha/bin/_mocha -- --slow=5000 --timeout=20000 ./test/unit/*.js",
+    "test-clean": "npm run clean && npm install && npm test",
+    "test-leak": "./test/leak/leak.sh",
+    "test-win32-node": "node ./node_modules/mocha/bin/mocha --slow=5000 --timeout=30000 ./test/unit/*.js",
+    "test-win32-iojs": "iojs ./node_modules/mocha/bin/mocha --slow=5000 --timeout=30000 ./test/unit/*.js"
   },
   "main": "index.js",
   "repository": {
@@ -27,6 +38,7 @@
     "png",
     "webp",
     "tiff",
+    "dzi",
     "resize",
     "thumbnail",
     "crop",
@@ -34,19 +46,24 @@
     "vips"
   ],
   "dependencies": {
-    "bluebird": "^2.9.9",
-    "color": "^0.7.3",
-    "nan": "^1.6.2",
-    "semver": "^4.3.0"
+    "bluebird": "^2.9.34",
+    "color": "^0.10.1",
+    "nan": "^2.0.8",
+    "semver": "^5.0.1"
   },
   "devDependencies": {
-    "mocha": "^2.1.0",
-    "mocha-jshint": "^0.0.9",
-    "istanbul": "^0.3.5",
-    "coveralls": "^2.11.2",
-    "node-cpplint": "^0.4.0"
+    "async": "^1.4.2",
+    "coveralls": "^2.11.4",
+    "exif-reader": "1.0.0",
+    "icc": "^0.0.2",
+    "istanbul": "^0.3.19",
+    "mocha": "^2.3.2",
+    "mocha-jshint": "^2.2.3",
+    "node-cpplint": "^0.4.0",
+    "rimraf": "^2.4.3",
+    "bufferutil": "^1.2.1"
   },
-  "license": "Apache 2.0",
+  "license": "Apache-2.0",
   "engines": {
     "node": ">=0.10"
   }

preinstall.sh

@@ -2,7 +2,6 @@
 
 # Ensures libvips is installed and attempts to install it if not
 # Currently supports:
-# * Mac OS
 # * Debian Linux
 #   * Debian 7, 8
 #   * Ubuntu 12.04, 14.04, 14.10, 15.04
@@ -10,53 +9,106 @@
 # * Red Hat Linux
 #   * RHEL/Centos/Scientific 6, 7
 #   * Fedora 21, 22
-#   * Amazon Linux 2014.09
+#   * Amazon Linux 2014.09, 2015.03
 
 vips_version_minimum=7.40.0
-vips_version_latest_major=7.42
-vips_version_latest_minor=2
+vips_version_latest_major_minor=8.0
+vips_version_latest_patch=2
+
+openslide_version_minimum=3.4.0
+openslide_version_latest_major_minor=3.4
+openslide_version_latest_patch=1
 
 install_libvips_from_source() {
-  echo "Compiling libvips $vips_version_latest_major.$vips_version_latest_minor from source"
-  curl -O http://www.vips.ecs.soton.ac.uk/supported/$vips_version_latest_major/vips-$vips_version_latest_major.$vips_version_latest_minor.tar.gz
-  tar zvxf vips-$vips_version_latest_major.$vips_version_latest_minor.tar.gz
-  cd vips-$vips_version_latest_major.$vips_version_latest_minor
-  ./configure --enable-debug=no --enable-docs=no --enable-cxx=yes --without-python --without-orc --without-fftw --without-gsf $1
+  echo "Compiling libvips $vips_version_latest_major_minor.$vips_version_latest_patch from source"
+  curl -O http://www.vips.ecs.soton.ac.uk/supported/$vips_version_latest_major_minor/vips-$vips_version_latest_major_minor.$vips_version_latest_patch.tar.gz
+  tar zvxf vips-$vips_version_latest_major_minor.$vips_version_latest_patch.tar.gz
+  cd vips-$vips_version_latest_major_minor.$vips_version_latest_patch
+  ./configure --disable-debug --disable-docs --disable-static --disable-introspection --enable-cxx=yes --without-python --without-orc --without-fftw $1
   make
   make install
   cd ..
-  rm -rf vips-$vips_version_latest_major.$vips_version_latest_minor
-  rm vips-$vips_version_latest_major.$vips_version_latest_minor.tar.gz
+  rm -rf vips-$vips_version_latest_major_minor.$vips_version_latest_patch
+  rm vips-$vips_version_latest_major_minor.$vips_version_latest_patch.tar.gz
   ldconfig
-  echo "Installed libvips $vips_version_latest_major.$vips_version_latest_minor"
+  echo "Installed libvips $vips_version_latest_major_minor.$vips_version_latest_patch"
+}
+
+install_libopenslide_from_source() {
+  echo "Compiling openslide $openslide_version_latest_major_minor.$openslide_version_latest_patch from source"
+  curl -O -L https://github.com/openslide/openslide/releases/download/v$openslide_version_latest_major_minor.$openslide_version_latest_patch/openslide-$openslide_version_latest_major_minor.$openslide_version_latest_patch.tar.gz
+  tar xzvf openslide-$openslide_version_latest_major_minor.$openslide_version_latest_patch.tar.gz
+  cd openslide-$openslide_version_latest_major_minor.$openslide_version_latest_patch
+  PKG_CONFIG_PATH=$pkg_config_path ./configure $1
+  make
+  make install
+  cd ..
+  rm -rf openslide-$openslide_version_latest_major_minor.$openslide_version_latest_patch
+  rm openslide-$openslide_version_latest_major_minor.$openslide_version_latest_patch.tar.gz
+  ldconfig
+  echo "Installed libopenslide $openslide_version_latest_major_minor.$openslide_version_latest_patch"
 }
 
 sorry() {
-  echo "Sorry, I don't yet know how to install libvips on $1"
+  echo "Sorry, I don't yet know how to install lib$1 on $2"
   exit 1
 }
 
-# Is libvips already installed, and is it at least the minimum required version?
+pkg_config_path="$PKG_CONFIG_PATH:/usr/local/lib/pkgconfig:/usr/lib/pkgconfig"
 
-if ! type pkg-config >/dev/null; then
-  sorry "a system without pkg-config"
+check_if_library_exists() {
+  PKG_CONFIG_PATH=$pkg_config_path pkg-config --exists $1
+  if [ $? -eq 0 ]; then
+    version_found=$(PKG_CONFIG_PATH=$pkg_config_path pkg-config --modversion $1)
+    PKG_CONFIG_PATH=$pkg_config_path pkg-config --atleast-version=$2 $1
+    if [ $? -eq 0 ]; then
+      # Found suitable version of libvips
+      echo "Found lib$1 $version_found"
+      return 1
+    fi
+    echo "Found lib$1 $version_found but require $2"
+  else
+    echo "Could not find lib$1 using a PKG_CONFIG_PATH of '$pkg_config_path'"
+  fi
+  return 0
+}
+
+enable_openslide=0
+# Is libvips already installed, and is it at least the minimum required version?
+if [ $# -eq 1 ]; then
+  if [ "$1" = "--with-openslide" ]; then
+    echo "Installing vips with openslide support"
+    enable_openslide=1
+  else
+    echo "Sorry, $1 is not supported. Did you mean --with-openslide?"
+    exit 1
+  fi
 fi
 
-pkg_config_path_homebrew=`which brew >/dev/null 2>&1 && eval $(brew --env) && echo $PKG_CONFIG_LIBDIR || true`
-pkg_config_path="$pkg_config_path_homebrew:$PKG_CONFIG_PATH:/usr/local/lib/pkgconfig:/usr/lib/pkgconfig"
+if ! type pkg-config >/dev/null; then
+  sorry "vips" "a system without pkg-config"
+fi
 
-PKG_CONFIG_PATH=$pkg_config_path pkg-config --exists vips
-if [ $? -eq 0 ]; then
-  vips_version_found=$(PKG_CONFIG_PATH=$pkg_config_path pkg-config --modversion vips)
-  pkg-config --atleast-version=$vips_version_minimum vips
-  if [ $? -eq 0 ]; then
-    # Found suitable version of libvips
-    echo "Found libvips $vips_version_found"
-    exit 0
+openslide_exists=0
+if [ $enable_openslide -eq 1 ]; then
+  check_if_library_exists "openslide" "$openslide_version_minimum"
+  openslide_exists=$?
+fi
+
+check_if_library_exists "vips" "$vips_version_minimum"
+vips_exists=$?
+if [ $vips_exists -eq 1 ] && [ $enable_openslide -eq 1 ]; then
+  if [ $openslide_exists -eq 1 ]; then
+    # Check if vips compiled with openslide support
+    vips_with_openslide=`vips list classes | grep -i opensli`
+    if [ -z $vips_with_openslide ]; then
+      echo "Vips compiled without openslide support."
+    else
+      exit 0
+    fi
   fi
-  echo "Found libvips $vips_version_found but require $vips_version_minimum"
-else
-  echo "Could not find libvips using a PKG_CONFIG_PATH of '$pkg_config_path'"
+elif [ $vips_exists -eq 1 ] && [ $enable_openslide -eq 0 ]; then
+  exit 0
 fi
 
 # Verify root/sudo access
@@ -65,101 +117,208 @@ if [ "$(id -u)" -ne "0" ]; then
   exit 1
 fi
 
+# OS-specific installations of libopenslide follows
+# Either openslide does not exist, or vips is installed without openslide support
+if [ $enable_openslide -eq 1 ] && [ -z $vips_with_openslide ] && [ $openslide_exists -eq 0 ]; then
+  if [ -f /etc/debian_version ]; then
+    # Debian Linux
+    DISTRO=$(lsb_release -c -s)
+    echo "Detected Debian Linux '$DISTRO'"
+    case "$DISTRO" in
+      jessie|vivid)
+        # Debian 8, Ubuntu 15
+        echo "Installing libopenslide via apt-get"
+        apt-get install -y libopenslide-dev
+        ;;
+      trusty|utopic|qiana|rebecca|rafaela)
+        # Ubuntu 14, Mint 17
+        echo "Installing libopenslide dependencies via apt-get"
+        apt-get install -y automake build-essential curl zlib1g-dev libopenjpeg-dev libpng12-dev libjpeg-dev libtiff5-dev libgdk-pixbuf2.0-dev libxml2-dev libsqlite3-dev libcairo2-dev libglib2.0-dev sqlite3 libsqlite3-dev
+        install_libopenslide_from_source
+        ;;
+      precise|wheezy|maya)
+        # Debian 7, Ubuntu 12.04, Mint 13
+        echo "Installing libopenslide dependencies via apt-get"
+        apt-get install -y automake build-essential curl zlib1g-dev libopenjpeg-dev libpng12-dev libjpeg-dev libtiff5-dev libgdk-pixbuf2.0-dev libxml2-dev libsqlite3-dev libcairo2-dev libglib2.0-dev sqlite3 libsqlite3-dev
+        install_libopenslide_from_source
+        ;;
+      *)
+        # Unsupported Debian-based OS
+        sorry "openslide" "Debian-based $DISTRO"
+        ;;
+    esac
+  elif [ -f /etc/redhat-release ]; then
+    # Red Hat Linux
+    RELEASE=$(cat /etc/redhat-release)
+    echo "Detected Red Hat Linux '$RELEASE'"
+    case $RELEASE in
+      "Red Hat Enterprise Linux release 7."*|"CentOS Linux release 7."*|"Scientific Linux release 7."*)
+        # RHEL/CentOS 7
+        echo "Installing libopenslide dependencies via yum"
+        yum groupinstall -y "Development Tools"
+        yum install -y tar curl libpng-devel libjpeg-devel libxml2-devel zlib-devel openjpeg-devel libtiff-devel gdk-pixbuf2-devel sqlite-devel cairo-devel glib2-devel
+        install_libopenslide_from_source "--prefix=/usr"
+        ;;
+      "Red Hat Enterprise Linux release 6."*|"CentOS release 6."*|"Scientific Linux release 6."*)
+        # RHEL/CentOS 6
+        echo "Installing libopenslide dependencies via yum"
+        yum groupinstall -y "Development Tools"
+        yum install -y tar curl libpng-devel libjpeg-devel libxml2-devel zlib-devel openjpeg-devel libtiff-devel gdk-pixbuf2-devel sqlite-devel cairo-devel glib2-devel
+        install_libopenslide_from_source "--prefix=/usr"
+        ;;
+      "Fedora release 21 "*|"Fedora release 22 "*)
+        # Fedora 21, 22
+        echo "Installing libopenslide via yum"
+        yum install -y openslide-devel
+        ;;
+      *)
+        # Unsupported RHEL-based OS
+        sorry "openslide" "$RELEASE"
+        ;;
+    esac
+  elif [ -f /etc/os-release ]; then
+    RELEASE=$(cat /etc/os-release | grep VERSION)
+    echo "Detected OpenSuse Linux '$RELEASE'"
+    case $RELEASE in
+      *"13.2"*)
+      echo "Installing libopenslide via zypper"
+      zypper --gpg-auto-import-keys install -y libopenslide-devel
+      ;;
+    esac
+  elif [ -f /etc/SuSE-brand ]; then
+    RELEASE=$(cat /etc/SuSE-brand | grep VERSION)
+    echo "Detected OpenSuse Linux '$RELEASE'"
+    case $RELEASE in
+      *"13.1")
+      echo "Installing libopenslide dependencies via zypper"
+      zypper --gpg-auto-import-keys install -y --type pattern devel_basis
+      zypper --gpg-auto-import-keys install -y tar curl libpng16-devel libjpeg-turbo libjpeg8-devel libxml2-devel zlib-devel openjpeg-devel libtiff-devel libgdk_pixbuf-2_0-0 sqlite3-devel cairo-devel glib2-devel
+      install_libopenslide_from_source
+      ;;
+    esac
+  else
+    # Unsupported OS
+    sorry "openslide" "$(uname -a)"
+  fi
+fi
+
 # OS-specific installations of libvips follows
 
-case $(uname -s) in
-  *[Dd]arwin*)
-    # Mac OS
-    echo "Detected Mac OS"
-    if type "brew" > /dev/null; then
-      echo "Installing libvips via homebrew"
-      brew install homebrew/science/vips --with-webp --with-graphicsmagick
-    elif type "port" > /dev/null; then
-      echo "Installing libvips via MacPorts"
-      port install vips
-    else
-      sorry "Mac OS without homebrew or MacPorts"
-    fi
+if [ -f /etc/debian_version ]; then
+  # Debian Linux
+  DISTRO=$(lsb_release -c -s)
+  echo "Detected Debian Linux '$DISTRO'"
+  case "$DISTRO" in
+    jessie|vivid)
+      # Debian 8, Ubuntu 15
+      if [ $enable_openslide -eq 1 ]; then
+        echo "Recompiling vips with openslide support"
+        install_libvips_from_source
+      else
+        echo "Installing libvips via apt-get"
+        apt-get install -y libvips-dev libgsf-1-dev
+      fi
+      ;;
+    trusty|utopic|qiana|rebecca|rafaela)
+      # Ubuntu 14, Mint 17
+      echo "Installing libvips dependencies via apt-get"
+      apt-get install -y automake build-essential gobject-introspection gtk-doc-tools libglib2.0-dev libjpeg-dev libpng12-dev libwebp-dev libtiff5-dev libexif-dev libgsf-1-dev liblcms2-dev libxml2-dev swig libmagickcore-dev curl
+      install_libvips_from_source
+      ;;
+    precise|wheezy|maya)
+      # Debian 7, Ubuntu 12.04, Mint 13
+      echo "Installing libvips dependencies via apt-get"
+      add-apt-repository -y ppa:lyrasis/precise-backports
+      apt-get update
+      apt-get install -y automake build-essential gobject-introspection gtk-doc-tools libglib2.0-dev libjpeg-dev libpng12-dev libwebp-dev libtiff4-dev libexif-dev libgsf-1-dev liblcms2-dev libxml2-dev swig libmagickcore-dev curl
+      install_libvips_from_source
+      ;;
+    *)
+      # Unsupported Debian-based OS
+      sorry "vips" "Debian-based $DISTRO"
+      ;;
+  esac
+elif [ -f /etc/redhat-release ]; then
+  # Red Hat Linux
+  RELEASE=$(cat /etc/redhat-release)
+  echo "Detected Red Hat Linux '$RELEASE'"
+  case $RELEASE in
+    "Red Hat Enterprise Linux release 7."*|"CentOS Linux release 7."*|"Scientific Linux release 7."*)
+      # RHEL/CentOS 7
+      echo "Installing libvips dependencies via yum"
+      yum groupinstall -y "Development Tools"
+      yum install -y gtk-doc libxml2-devel libjpeg-turbo-devel libpng-devel libtiff-devel libexif-devel libgsf-devel lcms-devel ImageMagick-devel gobject-introspection-devel libwebp-devel curl
+      install_libvips_from_source "--prefix=/usr"
+      ;;
+    "Red Hat Enterprise Linux release 6."*|"CentOS release 6."*|"Scientific Linux release 6."*)
+      # RHEL/CentOS 6
+      echo "Installing libvips dependencies via yum"
+      yum groupinstall -y "Development Tools"
+      yum install -y gtk-doc libxml2-devel libjpeg-turbo-devel libpng-devel libtiff-devel libexif-devel libgsf-devel lcms-devel ImageMagick-devel curl
+      yum install -y http://li.nux.ro/download/nux/dextop/el6/x86_64/nux-dextop-release-0-2.el6.nux.noarch.rpm
+      yum install -y --enablerepo=nux-dextop gobject-introspection-devel
+      yum install -y http://rpms.famillecollet.com/enterprise/remi-release-6.rpm
+      yum install -y --enablerepo=remi libwebp-devel
+      install_libvips_from_source "--prefix=/usr"
+      ;;
+    "Fedora release 21 "*|"Fedora release 22 "*)
+      # Fedora 21, 22
+      if [ $enable_openslide -eq 1 ]; then
+        echo "Installing libvips dependencies via yum"
+        yum groupinstall -y "Development Tools"
+        yum install -y gcc-c++ gtk-doc libxml2-devel libjpeg-turbo-devel libpng-devel libtiff-devel libexif-devel lcms-devel ImageMagick-devel gobject-introspection-devel libwebp-devel curl
+        echo "Compiling vips with openslide support"
+        install_libvips_from_source "--prefix=/usr"
+      else
+        echo "Installing libvips via yum"
+        yum install -y vips-devel
+      fi
+      ;;
+    *)
+      # Unsupported RHEL-based OS
+      sorry "vips" "$RELEASE"
+      ;;
+  esac
+elif [ -f /etc/system-release ]; then
+  # Probably Amazon Linux
+  RELEASE=$(cat /etc/system-release)
+  case $RELEASE in
+    "Amazon Linux AMI release 2014.09"|"Amazon Linux AMI release 2015.03")
+      # Amazon Linux
+      echo "Detected '$RELEASE'"
+      echo "Installing libvips dependencies via yum"
+      yum groupinstall -y "Development Tools"
+      yum install -y gtk-doc libxml2-devel libjpeg-turbo-devel libpng-devel libtiff-devel libexif-devel libgsf-devel lcms-devel ImageMagick-devel gobject-introspection-devel libwebp-devel curl
+      install_libvips_from_source "--prefix=/usr"
+      ;;
+    *)
+      # Unsupported Amazon Linux version
+      sorry "vips" "$RELEASE"
+      ;;
+  esac
+elif [ -f /etc/os-release ]; then
+  RELEASE=$(cat /etc/os-release | grep VERSION)
+  echo "Detected OpenSuse Linux '$RELEASE'"
+  case $RELEASE in
+    *"13.2"*)
+    echo "Installing libvips dependencies via zypper"
+    zypper --gpg-auto-import-keys install -y --type pattern devel_basis
+    zypper --gpg-auto-import-keys install -y tar curl gtk-doc libxml2-devel libjpeg-turbo libjpeg8-devel libpng16-devel libtiff-devel libexif-devel liblcms2-devel ImageMagick-devel gobject-introspection-devel libwebp-devel
+    install_libvips_from_source
     ;;
-  *)
-    if [ -f /etc/debian_version ]; then
-      # Debian Linux
-      DISTRO=$(lsb_release -c -s)
-      echo "Detected Debian Linux '$DISTRO'"
-      case "$DISTRO" in
-        jessie|vivid)
-          # Debian 8, Ubuntu 15
-          echo "Installing libvips via apt-get"
-          apt-get install -y libvips-dev
-          ;;
-        trusty|utopic|qiana|rebecca)
-          # Ubuntu 14, Mint 17
-          echo "Installing libvips dependencies via apt-get"
-          apt-get install -y automake build-essential gobject-introspection gtk-doc-tools libglib2.0-dev libjpeg-turbo8-dev libpng12-dev libwebp-dev libtiff5-dev libexif-dev liblcms2-dev libxml2-dev swig libmagickcore-dev curl
-          install_libvips_from_source
-          ;;
-        precise|wheezy|maya)
-          # Debian 7, Ubuntu 12.04, Mint 13
-          echo "Installing libvips dependencies via apt-get"
-          add-apt-repository -y ppa:lyrasis/precise-backports
-          apt-get update
-          apt-get install -y automake build-essential gobject-introspection gtk-doc-tools libglib2.0-dev libjpeg-turbo8-dev libpng12-dev libwebp-dev libtiff4-dev libexif-dev liblcms2-dev libxml2-dev swig libmagickcore-dev curl
-          install_libvips_from_source
-          ;;
-        *)
-          # Unsupported Debian-based OS
-          sorry "Debian-based $DISTRO"
-          ;;
-      esac
-    elif [ -f /etc/redhat-release ]; then
-      # Red Hat Linux
-      RELEASE=$(cat /etc/redhat-release)
-      echo "Detected Red Hat Linux '$RELEASE'"
-      case $RELEASE in
-        "Red Hat Enterprise Linux release 7."*|"CentOS Linux release 7."*|"Scientific Linux release 7."*)
-          # RHEL/CentOS 7
-          echo "Installing libvips dependencies via yum"
-          yum groupinstall -y "Development Tools"
-          yum install -y gtk-doc libxml2-devel libjpeg-turbo-devel libpng-devel libtiff-devel libexif-devel lcms-devel ImageMagick-devel gobject-introspection-devel libwebp-devel curl
-          install_libvips_from_source "--prefix=/usr"
-          ;;
-        "Red Hat Enterprise Linux release 6."*|"CentOS release 6."*|"Scientific Linux release 6."*)
-          # RHEL/CentOS 6
-          echo "Installing libvips dependencies via yum"
-          yum groupinstall -y "Development Tools"
-          yum install -y gtk-doc libxml2-devel libjpeg-turbo-devel libpng-devel libtiff-devel libexif-devel lcms-devel ImageMagick-devel curl
-          yum install -y http://li.nux.ro/download/nux/dextop/el6/x86_64/nux-dextop-release-0-2.el6.nux.noarch.rpm
-          yum install -y --enablerepo=nux-dextop gobject-introspection-devel
-          yum install -y http://rpms.famillecollet.com/enterprise/remi-release-6.rpm
-          yum install -y --enablerepo=remi libwebp-devel
-          install_libvips_from_source "--prefix=/usr"
-          ;;
-        "Fedora release 21 "*|"Fedora release 22 "*)
-          # Fedora 21, 22
-          echo "Installing libvips via yum"
-          yum install -y vips-devel
-          ;;
-        *)
-          # Unsupported RHEL-based OS
-          sorry "$RELEASE"
-          ;;
-      esac
-    elif [ -f /etc/system-release ]; then
-      # Probably Amazon Linux
-      RELEASE=$(cat /etc/system-release)
-      case $RELEASE in
-        "Amazon Linux AMI release 2014.09")
-          # Amazon Linux
-          echo "Detected '$RELEASE'"
-          echo "Installing libvips dependencies via yum"
-          yum groupinstall -y "Development Tools"
-          yum install -y gtk-doc libxml2-devel libjpeg-turbo-devel libpng-devel libtiff-devel libexif-devel lcms-devel ImageMagick-devel gobject-introspection-devel libwebp-devel curl
-          install_libvips_from_source "--prefix=/usr"
-          ;;
-      esac
-    else
-      # Unsupported OS
-      sorry "$(uname -a)"
-    fi
+  esac
+elif [ -f /etc/SuSE-brand ]; then
+  RELEASE=$(cat /etc/SuSE-brand | grep VERSION)
+  echo "Detected OpenSuse Linux '$RELEASE'"
+  case $RELEASE in
+    *"13.1")
+    echo "Installing libvips dependencies via zypper"
+    zypper --gpg-auto-import-keys install -y --type pattern devel_basis
+    zypper --gpg-auto-import-keys install -y tar curl gtk-doc libxml2-devel libjpeg-turbo libjpeg8-devel libpng16-devel libtiff-devel libexif-devel liblcms2-devel ImageMagick-devel gobject-introspection-devel libwebp-devel
+    install_libvips_from_source
     ;;
-esac
+  esac
+else
+  # Unsupported OS
+  sorry "vips" "$(uname -a)"
+fi

src/common.cc

@@ -1,9 +1,32 @@
+#include <cstdlib>
 #include <string>
 #include <string.h>
 #include <vips/vips.h>
 
 #include "common.h"
 
+// Verify platform and compiler compatibility
+
+#if (VIPS_MAJOR_VERSION < 7 || (VIPS_MAJOR_VERSION == 7 && VIPS_MINOR_VERSION < 40))
+#error libvips version 7.40.0+ required - see http://sharp.dimens.io/page/install
+#endif
+
+#ifdef _WIN64
+#error Windows 64-bit is currently unsupported - see http://sharp.dimens.io/page/install#windows
+#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 http://sharp.dimens.io/page/install#prerequisites
+#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 http://sharp.dimens.io/page/install#prerequisites
+#endif
+#endif
+
+#define EXIF_IFD0_ORIENTATION "exif-ifd0-Orientation"
+
 namespace sharp {
 
   // How many tasks are in the queue?
@@ -28,19 +51,8 @@ namespace sharp {
   bool IsTiff(std::string const &str) {
     return EndsWith(str, ".tif") || EndsWith(str, ".tiff") || EndsWith(str, ".TIF") || EndsWith(str, ".TIFF");
   }
-
-  // Buffer content checkers
-  unsigned char const MARKER_JPEG[] = {0xff, 0xd8};
-  unsigned char const MARKER_PNG[] = {0x89, 0x50};
-  unsigned char const MARKER_WEBP[] = {0x52, 0x49};
-
-  static bool buffer_is_tiff(char *buffer, size_t len) {
-    return (
-      len >= 4 && (
-        (buffer[0] == 'M' && buffer[1] == 'M' && buffer[2] == '\0' && (buffer[3] == '*' || buffer[3] == '+')) ||
-        (buffer[0] == 'I' && buffer[1] == 'I' && (buffer[2] == '*' || buffer[2] == '+') && buffer[3] == '\0')
-      )
-    );
+  bool IsDz(std::string const &str) {
+    return EndsWith(str, ".dzi") || EndsWith(str, ".DZI");
   }
 
   /*
@@ -48,15 +60,19 @@ namespace sharp {
   */
   ImageType DetermineImageType(void *buffer, size_t const length) {
     ImageType imageType = ImageType::UNKNOWN;
-    if (length >= 4) {
-      if (memcmp(MARKER_JPEG, buffer, 2) == 0) {
+    char const *load = vips_foreign_find_load_buffer(buffer, length);
+    if (load != NULL) {
+      std::string loader = load;
+      if (EndsWith(loader, "JpegBuffer")) {
         imageType = ImageType::JPEG;
-      } else if (memcmp(MARKER_PNG, buffer, 2) == 0) {
+      } else if (EndsWith(loader, "PngBuffer")) {
         imageType = ImageType::PNG;
-      } else if (memcmp(MARKER_WEBP, buffer, 2) == 0) {
+      } else if (EndsWith(loader, "WebpBuffer")) {
         imageType = ImageType::WEBP;
-      } else if (buffer_is_tiff(static_cast<char*>(buffer), length)) {
+      } else if (EndsWith(loader, "TiffBuffer")) {
         imageType = ImageType::TIFF;
+      } else if (EndsWith(loader, "MagickBuffer")) {
+        imageType = ImageType::MAGICK;
       }
     }
     return imageType;
@@ -65,35 +81,31 @@ namespace sharp {
   /*
     Initialise and return a VipsImage from a buffer. Supports JPEG, PNG, WebP and TIFF.
   */
-  VipsImage* InitImage(ImageType imageType, void *buffer, size_t const length, VipsAccess const access) {
-    VipsImage *image = NULL;
-    if (imageType == ImageType::JPEG) {
-      vips_jpegload_buffer(buffer, length, &image, "access", access, NULL);
-    } else if (imageType == ImageType::PNG) {
-      vips_pngload_buffer(buffer, length, &image, "access", access, NULL);
-    } else if (imageType == ImageType::WEBP) {
-      vips_webpload_buffer(buffer, length, &image, "access", access, NULL);
-    } else if (imageType == ImageType::TIFF) {
-      vips_tiffload_buffer(buffer, length, &image, "access", access, NULL);
-    }
-    return image;
+  VipsImage* InitImage(void *buffer, size_t const length, VipsAccess const access) {
+    return vips_image_new_from_buffer(buffer, length, NULL, "access", access, NULL);
   }
 
   /*
-    Inpect the first 2-4 bytes of a file to determine image format
+    Determine image format, reads the first few bytes of the file
   */
   ImageType DetermineImageType(char const *file) {
     ImageType imageType = ImageType::UNKNOWN;
-    if (vips_foreign_is_a("jpegload", file)) {
-      imageType = ImageType::JPEG;
-    } else if (vips_foreign_is_a("pngload", file)) {
-      imageType = ImageType::PNG;
-    } else if (vips_foreign_is_a("webpload", file)) {
-      imageType = ImageType::WEBP;
-    } else if (vips_foreign_is_a("tiffload", file)) {
-      imageType = ImageType::TIFF;
-    } else if(vips_foreign_is_a("magickload", file)) {
-      imageType = ImageType::MAGICK;
+    char const *load = vips_foreign_find_load(file);
+    if (load != NULL) {
+      std::string 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, "Magick") || EndsWith(loader, "MagickFile")) {
+        imageType = ImageType::MAGICK;
+      }
     }
     return imageType;
   }
@@ -101,20 +113,8 @@ namespace sharp {
   /*
     Initialise and return a VipsImage from a file.
   */
-  VipsImage* InitImage(ImageType imageType, char const *file, VipsAccess const access) {
-    VipsImage *image = NULL;
-    if (imageType == ImageType::JPEG) {
-      vips_jpegload(file, &image, "access", access, NULL);
-    } else if (imageType == ImageType::PNG) {
-      vips_pngload(file, &image, "access", access, NULL);
-    } else if (imageType == ImageType::WEBP) {
-      vips_webpload(file, &image, "access", access, NULL);
-    } else if (imageType == ImageType::TIFF) {
-      vips_tiffload(file, &image, "access", access, NULL);
-    } else if (imageType == ImageType::MAGICK) {
-      vips_magickload(file, &image, "access", access, NULL);
-    }
-    return image;
+  VipsImage* InitImage(char const *file, VipsAccess const access) {
+    return vips_image_new_from_file(file, "access", access, NULL);
   }
 
   /*
@@ -143,20 +143,39 @@ namespace sharp {
     int orientation = 0;
     const char *exif;
     if (
-      vips_image_get_typeof(image, "exif-ifd0-Orientation") != 0 &&
-      !vips_image_get_string(image, "exif-ifd0-Orientation", &exif)
+      vips_image_get_typeof(image, EXIF_IFD0_ORIENTATION) != 0 &&
+      !vips_image_get_string(image, EXIF_IFD0_ORIENTATION, &exif)
     ) {
       orientation = atoi(&exif[0]);
     }
     return orientation;
   }
 
+  /*
+    Set EXIF Orientation of image.
+  */
+  void SetExifOrientation(VipsImage *image, int const orientation) {
+    char exif[3];
+    g_snprintf(exif, sizeof(exif), "%d", orientation);
+    vips_image_set_string(image, EXIF_IFD0_ORIENTATION, exif);
+  }
+
+  /*
+    Remove EXIF Orientation from image.
+  */
+  void RemoveExifOrientation(VipsImage *image) {
+    SetExifOrientation(image, 0);
+  }
+
   /*
     Returns the window size for the named interpolator. For example,
     a window size of 3 means a 3x3 pixel grid is used for the calculation.
   */
   int InterpolatorWindowSize(char const *name) {
     VipsInterpolate *interpolator = vips_interpolate_new(name);
+    if (interpolator == NULL) {
+      return -1;
+    }
     int window_size = vips_interpolate_get_window_size(interpolator);
     g_object_unref(interpolator);
     return window_size;

src/common.h

@@ -1,6 +1,8 @@
 #ifndef SRC_COMMON_H_
 #define SRC_COMMON_H_
 
+#include <string>
+
 namespace sharp {
 
   enum class ImageType {
@@ -9,7 +11,8 @@ namespace sharp {
     PNG,
     WEBP,
     TIFF,
-    MAGICK
+    MAGICK,
+    OPENSLIDE
   };
 
   // How many tasks are in the queue?
@@ -23,6 +26,7 @@ namespace sharp {
   bool IsPng(std::string const &str);
   bool IsWebp(std::string const &str);
   bool IsTiff(std::string const &str);
+  bool IsDz(std::string const &str);
 
   /*
     Determine image format of a buffer.
@@ -37,12 +41,12 @@ namespace sharp {
   /*
     Initialise and return a VipsImage from a buffer. Supports JPEG, PNG, WebP and TIFF.
   */
-  VipsImage* InitImage(ImageType imageType, void *buffer, size_t const length, VipsAccess const access);
+  VipsImage* InitImage(void *buffer, size_t const length, VipsAccess const access);
 
   /*
     Initialise and return a VipsImage from a file.
   */
-  VipsImage* InitImage(ImageType imageType, char const *file, VipsAccess const access);
+  VipsImage* InitImage(char const *file, VipsAccess const access);
 
   /*
     Does this image have an embedded profile?
@@ -60,6 +64,16 @@ namespace sharp {
   */
   int ExifOrientation(VipsImage const *image);
 
+  /*
+    Set EXIF Orientation of image.
+  */
+  void SetExifOrientation(VipsImage *image, int const orientation);
+
+  /*
+    Remove EXIF Orientation from image.
+  */
+  void RemoveExifOrientation(VipsImage *image);
+
   /*
     Returns the window size for the named interpolator. For example,
     a window size of 3 means a 3x3 pixel grid is used for the calculation.

src/metadata.cc

@@ -16,6 +16,19 @@ using v8::Boolean;
 using v8::Function;
 using v8::Exception;
 
+using Nan::AsyncQueueWorker;
+using Nan::AsyncWorker;
+using Nan::Callback;
+using Nan::HandleScope;
+using Nan::Utf8String;
+using Nan::Has;
+using Nan::Get;
+using Nan::Set;
+using Nan::New;
+using Nan::NewBuffer;
+using Nan::Null;
+using Nan::Error;
+
 using sharp::ImageType;
 using sharp::DetermineImageType;
 using sharp::InitImage;
@@ -27,7 +40,7 @@ using sharp::counterQueue;
 struct MetadataBaton {
   // Input
   std::string fileIn;
-  void* bufferIn;
+  char *bufferIn;
   size_t bufferInLength;
   // Output
   std::string format;
@@ -38,17 +51,33 @@ struct MetadataBaton {
   bool hasProfile;
   bool hasAlpha;
   int orientation;
+  char *exif;
+  size_t exifLength;
+  char *icc;
+  size_t iccLength;
   std::string err;
 
   MetadataBaton():
     bufferInLength(0),
-    orientation(0) {}
+    orientation(0),
+    exifLength(0),
+    iccLength(0) {}
 };
 
-class MetadataWorker : public NanAsyncWorker {
+/*
+  Delete input char[] buffer and notify V8 of memory deallocation
+  Used as the callback function for the "postclose" signal
+*/
+static void DeleteBuffer(VipsObject *object, char *buffer) {
+  if (buffer != NULL) {
+    delete[] buffer;
+  }
+}
+
+class MetadataWorker : public AsyncWorker {
 
  public:
-  MetadataWorker(NanCallback *callback, MetadataBaton *baton) : NanAsyncWorker(callback), baton(baton) {}
+  MetadataWorker(Callback *callback, MetadataBaton *baton) : AsyncWorker(callback), baton(baton) {}
   ~MetadataWorker() {}
 
   void Execute() {
@@ -57,23 +86,28 @@ class MetadataWorker : public NanAsyncWorker {
 
     ImageType imageType = ImageType::UNKNOWN;
     VipsImage *image = NULL;
-    if (baton->bufferInLength > 1) {
+    if (baton->bufferInLength > 0) {
       // From buffer
       imageType = DetermineImageType(baton->bufferIn, baton->bufferInLength);
       if (imageType != ImageType::UNKNOWN) {
-        image = InitImage(imageType, baton->bufferIn, baton->bufferInLength, VIPS_ACCESS_RANDOM);
-        if (image == NULL) {
+        image = InitImage(baton->bufferIn, baton->bufferInLength, VIPS_ACCESS_RANDOM);
+        if (image != NULL) {
+          // Listen for "postclose" signal to delete input buffer
+          g_signal_connect(image, "postclose", G_CALLBACK(DeleteBuffer), baton->bufferIn);
+        } else {
           (baton->err).append("Input buffer has corrupt header");
           imageType = ImageType::UNKNOWN;
+          DeleteBuffer(NULL, baton->bufferIn);
         }
       } else {
         (baton->err).append("Input buffer contains unsupported image format");
+        DeleteBuffer(NULL, baton->bufferIn);
       }
     } else {
       // From file
       imageType = DetermineImageType(baton->fileIn.c_str());
       if (imageType != ImageType::UNKNOWN) {
-        image = InitImage(imageType, baton->fileIn.c_str(), VIPS_ACCESS_RANDOM);
+        image = InitImage(baton->fileIn.c_str(), VIPS_ACCESS_RANDOM);
         if (image == NULL) {
           (baton->err).append("Input file has corrupt header");
           imageType = ImageType::UNKNOWN;
@@ -90,6 +124,7 @@ class MetadataWorker : public NanAsyncWorker {
         case ImageType::WEBP: baton->format = "webp"; break;
         case ImageType::TIFF: baton->format = "tiff"; break;
         case ImageType::MAGICK: baton->format = "magick"; break;
+        case ImageType::OPENSLIDE: baton->format = "openslide"; break;
         case ImageType::UNKNOWN: break;
       }
       // VipsImage attributes
@@ -101,6 +136,26 @@ class MetadataWorker : public NanAsyncWorker {
       // Derived attributes
       baton->hasAlpha = HasAlpha(image);
       baton->orientation = ExifOrientation(image);
+      // EXIF
+      if (vips_image_get_typeof(image, VIPS_META_EXIF_NAME) == VIPS_TYPE_BLOB) {
+        void* exif;
+        size_t exifLength;
+        if (!vips_image_get_blob(image, VIPS_META_EXIF_NAME, &exif, &exifLength)) {
+          baton->exifLength = exifLength;
+          baton->exif = static_cast<char*>(malloc(exifLength));
+          memcpy(baton->exif, exif, exifLength);
+        }
+      }
+      // ICC profile
+      if (vips_image_get_typeof(image, VIPS_META_ICC_NAME) == VIPS_TYPE_BLOB) {
+        void* icc;
+        size_t iccLength;
+        if (!vips_image_get_blob(image, VIPS_META_ICC_NAME, &icc, &iccLength)) {
+          baton->iccLength = iccLength;
+          baton->icc = static_cast<char*>(malloc(iccLength));
+          memcpy(baton->icc, icc, iccLength);
+        }
+      }
       // Drop image reference
       g_object_unref(image);
     }
@@ -110,24 +165,30 @@ class MetadataWorker : public NanAsyncWorker {
   }
 
   void HandleOKCallback () {
-    NanScope();
+    HandleScope();
 
-    Handle<Value> argv[2] = { NanNull(), NanNull() };
+    Local<Value> argv[2] = { Null(), Null() };
     if (!baton->err.empty()) {
       // Error
-      argv[0] = Exception::Error(NanNew<String>(baton->err.data(), baton->err.size()));
+      argv[0] = Error(baton->err.c_str());
     } else {
       // Metadata Object
-      Local<Object> info = NanNew<Object>();
-      info->Set(NanNew<String>("format"), NanNew<String>(baton->format));
-      info->Set(NanNew<String>("width"), NanNew<Number>(baton->width));
-      info->Set(NanNew<String>("height"), NanNew<Number>(baton->height));
-      info->Set(NanNew<String>("space"), NanNew<String>(baton->space));
-      info->Set(NanNew<String>("channels"), NanNew<Number>(baton->channels));
-      info->Set(NanNew<String>("hasProfile"), NanNew<Boolean>(baton->hasProfile));
-      info->Set(NanNew<String>("hasAlpha"), NanNew<Boolean>(baton->hasAlpha));
+      Local<Object> info = New<Object>();
+      Set(info, New("format").ToLocalChecked(), New<String>(baton->format).ToLocalChecked());
+      Set(info, New("width").ToLocalChecked(), New<Number>(baton->width));
+      Set(info, New("height").ToLocalChecked(), New<Number>(baton->height));
+      Set(info, New("space").ToLocalChecked(), New<String>(baton->space).ToLocalChecked());
+      Set(info, New("channels").ToLocalChecked(), New<Number>(baton->channels));
+      Set(info, New("hasProfile").ToLocalChecked(), New<Boolean>(baton->hasProfile));
+      Set(info, New("hasAlpha").ToLocalChecked(), New<Boolean>(baton->hasAlpha));
       if (baton->orientation > 0) {
-        info->Set(NanNew<String>("orientation"), NanNew<Number>(baton->orientation));
+        Set(info, New("orientation").ToLocalChecked(), New<Number>(baton->orientation));
+      }
+      if (baton->exifLength > 0) {
+        Set(info, New("exif").ToLocalChecked(), NewBuffer(baton->exif, baton->exifLength).ToLocalChecked());
+      }
+      if (baton->iccLength > 0) {
+        Set(info, New("icc").ToLocalChecked(), NewBuffer(baton->icc, baton->iccLength).ToLocalChecked());
       }
       argv[1] = info;
     }
@@ -145,27 +206,27 @@ class MetadataWorker : public NanAsyncWorker {
   metadata(options, callback)
 */
 NAN_METHOD(metadata) {
-  NanScope();
+  HandleScope();
 
   // V8 objects are converted to non-V8 types held in the baton struct
   MetadataBaton *baton = new MetadataBaton;
-  Local<Object> options = args[0]->ToObject();
+  Local<Object> options = info[0].As<Object>();
 
   // Input filename
-  baton->fileIn = *String::Utf8Value(options->Get(NanNew<String>("fileIn"))->ToString());
+  baton->fileIn = *Utf8String(Get(options, New("fileIn").ToLocalChecked()).ToLocalChecked());
   // Input Buffer object
-  if (options->Get(NanNew<String>("bufferIn"))->IsObject()) {
-    Local<Object> buffer = options->Get(NanNew<String>("bufferIn"))->ToObject();
+  if (node::Buffer::HasInstance(Get(options, New("bufferIn").ToLocalChecked()).ToLocalChecked())) {
+    Local<Object> buffer = Get(options, New("bufferIn").ToLocalChecked()).ToLocalChecked().As<Object>();
+    // Take a copy of the input Buffer to avoid problems with V8 heap compaction
     baton->bufferInLength = node::Buffer::Length(buffer);
-    baton->bufferIn = node::Buffer::Data(buffer);
+    baton->bufferIn = new char[baton->bufferInLength];
+    memcpy(baton->bufferIn, node::Buffer::Data(buffer), baton->bufferInLength);
   }
 
   // Join queue for worker thread
-  NanCallback *callback = new NanCallback(args[1].As<v8::Function>());
-  NanAsyncQueueWorker(new MetadataWorker(callback, baton));
+  Callback *callback = new Callback(info[1].As<Function>());
+  AsyncQueueWorker(new MetadataWorker(callback, baton));
 
   // Increment queued task counter
   g_atomic_int_inc(&counterQueue);
-
-  NanReturnUndefined();
 }

src/operations.cc

@@ -0,0 +1,333 @@
+#include <vips/vips.h>
+
+#include "common.h"
+#include "operations.h"
+
+namespace sharp {
+
+  /*
+    Alpha composite src over dst
+    Assumes alpha channels are already premultiplied and will be unpremultiplied after
+   */
+  int Composite(VipsObject *context, VipsImage *src, VipsImage *dst, VipsImage **out) {
+    using sharp::HasAlpha;
+
+    // Split src into non-alpha and alpha
+    VipsImage *srcWithoutAlpha;
+    if (vips_extract_band(src, &srcWithoutAlpha, 0, "n", src->Bands - 1, NULL))
+      return -1;
+    vips_object_local(context, srcWithoutAlpha);
+    VipsImage *srcAlpha;
+    if (vips_extract_band(src, &srcAlpha, src->Bands - 1, "n", 1, NULL))
+      return -1;
+    vips_object_local(context, srcAlpha);
+
+    // Split dst into non-alpha and alpha channels
+    VipsImage *dstWithoutAlpha;
+    VipsImage *dstAlpha;
+    if (HasAlpha(dst)) {
+      // Non-alpha: extract all-but-last channel
+      if (vips_extract_band(dst, &dstWithoutAlpha, 0, "n", dst->Bands - 1, NULL)) {
+        return -1;
+      }
+      vips_object_local(context, dstWithoutAlpha);
+      // Alpha: Extract last channel
+      if (vips_extract_band(dst, &dstAlpha, dst->Bands - 1, "n", 1, NULL)) {
+        return -1;
+      }
+      vips_object_local(context, dstAlpha);
+    } else {
+      // Non-alpha: Copy reference
+      dstWithoutAlpha = dst;
+      // Alpha: Use blank, opaque (0xFF) image
+      VipsImage *black;
+      if (vips_black(&black, dst->Xsize, dst->Ysize, NULL)) {
+        return -1;
+      }
+      vips_object_local(context, black);
+      if (vips_invert(black, &dstAlpha, NULL)) {
+        return -1;
+      }
+      vips_object_local(context, dstAlpha);
+    }
+
+    // Compute normalized input alpha channels:
+    VipsImage *srcAlphaNormalized;
+    if (vips_linear1(srcAlpha, &srcAlphaNormalized, 1.0 / 255.0, 0.0, NULL))
+      return -1;
+    vips_object_local(context, srcAlphaNormalized);
+
+    VipsImage *dstAlphaNormalized;
+    if (vips_linear1(dstAlpha, &dstAlphaNormalized, 1.0 / 255.0, 0.0, NULL))
+      return -1;
+    vips_object_local(context, dstAlphaNormalized);
+
+    //
+    // 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
+    //                 ^^^^^^^^^^^^^^^^^^^
+    //                         t1
+    VipsImage *t0;
+    if (vips_linear1(srcAlphaNormalized, &t0, -1.0, 1.0, NULL))
+      return -1;
+    vips_object_local(context, t0);
+
+    VipsImage *t1;
+    if (vips_multiply(dstAlphaNormalized, t0, &t1, NULL))
+      return -1;
+    vips_object_local(context, t1);
+
+    VipsImage *outAlphaNormalized;
+    if (vips_add(srcAlphaNormalized, t1, &outAlphaNormalized, NULL))
+      return -1;
+    vips_object_local(context, outAlphaNormalized);
+
+    //
+    // 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.
+    //
+    VipsImage *t2;
+    if (vips_multiply(dstWithoutAlpha, t0, &t2, NULL))
+      return -1;
+    vips_object_local(context, t2);
+
+    VipsImage *outRGBPremultiplied;
+    if (vips_add(srcWithoutAlpha, t2, &outRGBPremultiplied, NULL))
+      return -1;
+    vips_object_local(context, outRGBPremultiplied);
+
+    // Denormalize output alpha channel:
+    VipsImage *outAlpha;
+    if (vips_linear1(outAlphaNormalized, &outAlpha, 255.0, 0.0, NULL))
+      return -1;
+    vips_object_local(context, outAlpha);
+
+    // Combine RGB and alpha channel into output image:
+    return vips_bandjoin2(outRGBPremultiplied, outAlpha, out, NULL);
+  }
+
+  /*
+   * Premultiply alpha channel of `image`.
+   */
+  int Premultiply(VipsObject *context, VipsImage *image, VipsImage **out) {
+#if (VIPS_MAJOR_VERSION >= 9 || (VIPS_MAJOR_VERSION >= 8 && VIPS_MINOR_VERSION >= 1))
+    return vips_premultiply(image, out, NULL);
+#else
+    VipsImage *imageRGB;
+    if (vips_extract_band(image, &imageRGB, 0, "n", image->Bands - 1, NULL))
+      return -1;
+    vips_object_local(context, imageRGB);
+
+    VipsImage *imageAlpha;
+    if (vips_extract_band(image, &imageAlpha, image->Bands - 1, "n", 1, NULL))
+      return -1;
+    vips_object_local(context, imageAlpha);
+
+    VipsImage *imageAlphaNormalized;
+    if (vips_linear1(imageAlpha, &imageAlphaNormalized, 1.0 / 255.0, 0.0, NULL))
+      return -1;
+    vips_object_local(context, imageAlphaNormalized);
+
+    VipsImage *imageRGBPremultiplied;
+    if (vips_multiply(imageRGB, imageAlphaNormalized, &imageRGBPremultiplied, NULL))
+      return -1;
+    vips_object_local(context, imageRGBPremultiplied);
+
+    return vips_bandjoin2(imageRGBPremultiplied, imageAlpha, out, NULL);
+#endif
+  }
+
+  /*
+   * Unpremultiply alpha channel of `image`.
+   */
+  int Unpremultiply(VipsObject *context, VipsImage *image, VipsImage **out) {
+#if (VIPS_MAJOR_VERSION >= 9 || (VIPS_MAJOR_VERSION >= 8 && VIPS_MINOR_VERSION >= 1))
+    return vips_unpremultiply(image, out, NULL);
+#else
+    VipsImage *imageRGBPremultipliedTransformed;
+    if (vips_extract_band(image, &imageRGBPremultipliedTransformed, 0, "n", image->Bands - 1, NULL))
+      return -1;
+    vips_object_local(context, imageRGBPremultipliedTransformed);
+
+    VipsImage *imageAlphaTransformed;
+    if (vips_extract_band(image, &imageAlphaTransformed, image->Bands - 1, "n", 1, NULL))
+      return -1;
+    vips_object_local(context, imageAlphaTransformed);
+
+    VipsImage *imageAlphaNormalizedTransformed;
+    if (vips_linear1(imageAlphaTransformed, &imageAlphaNormalizedTransformed, 1.0 / 255.0, 0.0, NULL))
+      return -1;
+    vips_object_local(context, imageAlphaNormalizedTransformed);
+
+    VipsImage *imageRGBUnpremultipliedTransformed;
+    if (vips_divide(imageRGBPremultipliedTransformed, imageAlphaNormalizedTransformed, &imageRGBUnpremultipliedTransformed, NULL))
+      return -1;
+    vips_object_local(context, imageRGBUnpremultipliedTransformed);
+
+    return vips_bandjoin2(imageRGBUnpremultipliedTransformed, imageAlphaTransformed, out, NULL);
+#endif
+  }
+
+  /*
+   * Stretch luminance to cover full dynamic range.
+   */
+  int Normalize(VipsObject *context, VipsImage *image, VipsImage **out) {
+#ifndef _WIN32
+    // Get original colourspace
+    VipsInterpretation typeBeforeNormalize = image->Type;
+    if (typeBeforeNormalize == VIPS_INTERPRETATION_RGB) {
+      typeBeforeNormalize = VIPS_INTERPRETATION_sRGB;
+    }
+    // Convert to LAB colourspace
+    VipsImage *lab;
+    if (vips_colourspace(image, &lab, VIPS_INTERPRETATION_LAB, NULL)) {
+      return -1;
+    }
+    vips_object_local(context, lab);
+    // Extract luminance
+    VipsImage *luminance;
+    if (vips_extract_band(lab, &luminance, 0, "n", 1, NULL)) {
+      return -1;
+    }
+    vips_object_local(context, luminance);
+    // Extract chroma
+    VipsImage *chroma;
+    if (vips_extract_band(lab, &chroma, 1, "n", 2, NULL)) {
+      return -1;
+    }
+    vips_object_local(context, chroma);
+    // Find luminance range
+    VipsImage *stats;
+    if (vips_stats(luminance, &stats, NULL)) {
+      return -1;
+    }
+    vips_object_local(context, stats);
+    double min = *VIPS_MATRIX(stats, 0, 0);
+    double max = *VIPS_MATRIX(stats, 1, 0);
+    if (min != max) {
+      double f = 100.0 / (max - min);
+      double a = -(min * f);
+      // Scale luminance
+      VipsImage *luminance100;
+      if (vips_linear1(luminance, &luminance100, f, a, NULL)) {
+        return -1;
+      }
+      vips_object_local(context, luminance100);
+      // Join scaled luminance to chroma
+      VipsImage *normalizedLab;
+      if (vips_bandjoin2(luminance100, chroma, &normalizedLab, NULL)) {
+        return -1;
+      }
+      vips_object_local(context, normalizedLab);
+      // Convert to original colourspace
+      VipsImage *normalized;
+      if (vips_colourspace(normalizedLab, &normalized, typeBeforeNormalize, NULL)) {
+        return -1;
+      }
+      vips_object_local(context, normalized);
+      // Attach original alpha channel, if any
+      if (HasAlpha(image)) {
+        // Extract original alpha channel
+        VipsImage *alpha;
+        if (vips_extract_band(image, &alpha, image->Bands - 1, "n", 1, NULL)) {
+          return -1;
+        }
+        vips_object_local(context, alpha);
+        // Join alpha channel to normalised image
+        VipsImage *normalizedAlpha;
+        if (vips_bandjoin2(normalized, alpha, &normalizedAlpha, NULL)) {
+          return -1;
+        }
+        vips_object_local(context, normalizedAlpha);
+        *out = normalizedAlpha;
+      } else {
+        *out = normalized;
+      }
+    } else {
+      // Cannot normalise zero-range image
+      *out = image;
+    }
+#else
+    // The normalize operation is currently unsupported on Windows
+    // See https://github.com/lovell/sharp/issues/152
+    *out = image;
+#endif
+    return 0;
+  }
+
+  /*
+   * Gaussian blur (use sigma <0 for fast blur)
+   */
+  int Blur(VipsObject *context, VipsImage *image, VipsImage **out, double sigma) {
+    VipsImage *blurred;
+    if (sigma < 0.0) {
+      // Fast, mild blur - averages neighbouring pixels
+      VipsImage *blur = vips_image_new_matrixv(3, 3,
+        1.0, 1.0, 1.0,
+        1.0, 1.0, 1.0,
+        1.0, 1.0, 1.0);
+      vips_image_set_double(blur, "scale", 9);
+      vips_object_local(context, blur);
+      if (vips_conv(image, &blurred, blur, NULL)) {
+        return -1;
+      }
+    } else {
+      // Slower, accurate Gaussian blur
+      // Create Gaussian function for standard deviation
+      VipsImage *gaussian;
+      if (vips_gaussmat(&gaussian, sigma, 0.2, "separable", TRUE, "integer", TRUE, NULL)) {
+        return -1;
+      }
+      vips_object_local(context, gaussian);
+      // Apply Gaussian function
+      if (vips_convsep(image, &blurred, gaussian, "precision", VIPS_PRECISION_INTEGER, NULL)) {
+        return -1;
+      }
+    }
+    vips_object_local(context, blurred);
+    *out = blurred;
+    return 0;
+  }
+
+  /*
+   * Sharpen flat and jagged areas. Use radius of -1 for fast sharpen.
+   */
+  int Sharpen(VipsObject *context, VipsImage *image, VipsImage **out, int radius, double flat, double jagged) {
+    VipsImage *sharpened;
+    if (radius == -1) {
+      // Fast, mild sharpen
+      VipsImage *sharpen = vips_image_new_matrixv(3, 3,
+        -1.0, -1.0, -1.0,
+        -1.0, 32.0, -1.0,
+        -1.0, -1.0, -1.0);
+      vips_image_set_double(sharpen, "scale", 24);
+      vips_object_local(context, sharpen);
+      if (vips_conv(image, &sharpened, sharpen, NULL)) {
+        return -1;
+      }
+    } else {
+      // Slow, accurate sharpen in LAB colour space, with control over flat vs jagged areas
+      if (vips_sharpen(image, &sharpened, "radius", radius, "m1", flat, "m2", jagged, NULL)) {
+        return -1;
+      }
+    }
+    vips_object_local(context, sharpened);
+    *out = sharpened;
+    return 0;
+  }
+}  // namespace sharp

src/operations.h

@@ -0,0 +1,39 @@
+#ifndef SRC_OPERATIONS_H_
+#define SRC_OPERATIONS_H_
+
+namespace sharp {
+
+  /*
+    Composite images `src` and `dst` with premultiplied alpha channel and output
+    image with premultiplied alpha.
+   */
+  int Composite(VipsObject *context, VipsImage *src, VipsImage *dst, VipsImage **out);
+
+  /*
+   * Premultiply alpha channel of `image`.
+   */
+  int Premultiply(VipsObject *context, VipsImage *image, VipsImage **out);
+
+  /*
+   * Unpremultiply alpha channel of `image`.
+   */
+  int Unpremultiply(VipsObject *context, VipsImage *image, VipsImage **out);
+
+  /*
+   * Stretch luminance to cover full dynamic range.
+   */
+  int Normalize(VipsObject *context, VipsImage *image, VipsImage **out);
+
+  /*
+   * Gaussian blur. Use sigma of -1 for fast blur.
+   */
+  int Blur(VipsObject *context, VipsImage *image, VipsImage **out, double sigma);
+
+  /*
+   * Sharpen flat and jagged areas. Use radius of -1 for fast sharpen.
+   */
+  int Sharpen(VipsObject *context, VipsImage *image, VipsImage **out, int radius, double flat, double jagged);
+
+}  // namespace sharp
+
+#endif  // SRC_OPERATIONS_H_

src/pipeline.h

@@ -0,0 +1,8 @@
+#ifndef SRC_PIPELINE_H_
+#define SRC_PIPELINE_H_
+
+#include "nan.h"
+
+NAN_METHOD(pipeline);
+
+#endif  // SRC_PIPELINE_H_

src/resize.h

@@ -1,8 +0,0 @@
-#ifndef SRC_RESIZE_H_
-#define SRC_RESIZE_H_
-
-#include "nan.h"
-
-NAN_METHOD(resize);
-
-#endif  // SRC_RESIZE_H_

src/sharp.cc

@@ -5,11 +5,10 @@
 
 #include "common.h"
 #include "metadata.h"
-#include "resize.h"
+#include "pipeline.h"
 #include "utilities.h"
 
-extern "C" void init(v8::Handle<v8::Object> target) {
-  NanScope();
+NAN_MODULE_INIT(init) {
   vips_init("sharp");
 
   // Set libvips operation cache limits
@@ -17,12 +16,22 @@ extern "C" void init(v8::Handle<v8::Object> target) {
   vips_cache_set_max(500); // 500 operations
 
   // Methods available to JavaScript
-  NODE_SET_METHOD(target, "metadata", metadata);
-  NODE_SET_METHOD(target, "resize", resize);
-  NODE_SET_METHOD(target, "cache", cache);
-  NODE_SET_METHOD(target, "concurrency", concurrency);
-  NODE_SET_METHOD(target, "counters", counters);
-  NODE_SET_METHOD(target, "libvipsVersion", libvipsVersion);
+  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("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());
 }
 
 NODE_MODULE(sharp, init)

src/utilities.cc

@@ -4,77 +4,255 @@
 #include "nan.h"
 
 #include "common.h"
+#include "operations.h"
 #include "utilities.h"
 
 using v8::Local;
 using v8::Object;
 using v8::Number;
 using v8::String;
+using v8::Boolean;
 
-using sharp::counterQueue;
-using sharp::counterProcess;
+using Nan::HandleScope;
+using Nan::New;
+using Nan::Set;
+using Nan::ThrowError;
+using Nan::To;
+using Nan::Utf8String;
 
 /*
   Get and set cache memory and item limits
 */
 NAN_METHOD(cache) {
-  NanScope();
+  HandleScope();
 
   // Set cache memory limit
-  if (args[0]->IsInt32()) {
-    int newMax = args[0]->Int32Value() * 1048576;
-    int oldMax = vips_cache_get_max_mem();
-    vips_cache_set_max_mem(newMax);
-
-    // Notify the V8 garbage collector of delta in max cache size
-    NanAdjustExternalMemory(newMax - oldMax);
+  if (info[0]->IsInt32()) {
+    vips_cache_set_max_mem(To<int32_t>(info[0]).FromJust() * 1048576);
   }
 
   // Set cache items limit
-  if (args[1]->IsInt32()) {
-    vips_cache_set_max(args[1]->Int32Value());
+  if (info[1]->IsInt32()) {
+    vips_cache_set_max(To<int32_t>(info[1]).FromJust());
   }
 
   // Get cache statistics
-  Local<Object> cache = NanNew<Object>();
-  cache->Set(NanNew<String>("current"), NanNew<Number>(vips_tracked_get_mem() / 1048576));
-  cache->Set(NanNew<String>("high"), NanNew<Number>(vips_tracked_get_mem_highwater() / 1048576));
-  cache->Set(NanNew<String>("memory"), NanNew<Number>(vips_cache_get_max_mem() / 1048576));
-  cache->Set(NanNew<String>("items"), NanNew<Number>(vips_cache_get_max()));
-  NanReturnValue(cache);
+  Local<Object> cache = New<Object>();
+  Set(cache, New("current").ToLocalChecked(), New<Number>(vips_tracked_get_mem() / 1048576));
+  Set(cache, New("high").ToLocalChecked(), New<Number>(vips_tracked_get_mem_highwater() / 1048576));
+  Set(cache, New("memory").ToLocalChecked(), New<Number>(vips_cache_get_max_mem() / 1048576));
+  Set(cache, New("items").ToLocalChecked(), New<Number>(vips_cache_get_max()));
+  info.GetReturnValue().Set(cache);
 }
 
 /*
   Get and set size of thread pool
 */
 NAN_METHOD(concurrency) {
-  NanScope();
+  HandleScope();
 
   // Set concurrency
-  if (args[0]->IsInt32()) {
-    vips_concurrency_set(args[0]->Int32Value());
+  if (info[0]->IsInt32()) {
+    vips_concurrency_set(To<int32_t>(info[0]).FromJust());
   }
   // Get concurrency
-  NanReturnValue(NanNew<Number>(vips_concurrency_get()));
+  info.GetReturnValue().Set(New<Number>(vips_concurrency_get()));
 }
 
 /*
   Get internal counters (queued tasks, processing tasks)
 */
 NAN_METHOD(counters) {
-  NanScope();
-  Local<Object> counters = NanNew<Object>();
-  counters->Set(NanNew<String>("queue"), NanNew<Number>(counterQueue));
-  counters->Set(NanNew<String>("process"), NanNew<Number>(counterProcess));
-  NanReturnValue(counters);
+  using sharp::counterProcess;
+  using sharp::counterQueue;
+
+  HandleScope();
+  Local<Object> counters = New<Object>();
+  Set(counters, New("queue").ToLocalChecked(), New<Number>(counterQueue));
+  Set(counters, New("process").ToLocalChecked(), New<Number>(counterProcess));
+  info.GetReturnValue().Set(counters);
 }
 
 /*
   Get libvips version
 */
 NAN_METHOD(libvipsVersion) {
-  NanScope();
+  HandleScope();
   char version[9];
-  snprintf(version, sizeof(version), "%d.%d.%d", vips_version(0), vips_version(1), vips_version(2));
-  NanReturnValue(NanNew<String>(version));
+  g_snprintf(version, sizeof(version), "%d.%d.%d", vips_version(0), vips_version(1), vips_version(2));
+  info.GetReturnValue().Set(New(version).ToLocalChecked());
+}
+
+/*
+  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"}) {
+    // 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);
+    // 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);
+    // 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);
+    // Add to set of formats
+    Set(format, formatId, container);
+  }
+
+  // Raw, uncompressed data
+  Local<Object> raw = New<Object>();
+  Local<String> rawId = New("raw").ToLocalChecked();
+  Set(raw, attrId, rawId);
+  Set(format, rawId, raw);
+  // No support for raw input yet, so always false
+  Local<Boolean> unsupported = New<Boolean>(false);
+  Local<Object> rawInput = New<Object>();
+  Set(rawInput, attrFile, unsupported);
+  Set(rawInput, attrBuffer, unsupported);
+  Set(rawInput, attrStream, unsupported);
+  Set(raw, attrInput, rawInput);
+  // Raw output via Buffer/Stream is available in libvips >= 7.42.0
+  Local<Boolean> hasOutputBufferRaw = New<Boolean>(vips_version(0) >= 8 || (vips_version(0) == 7 && vips_version(1) >= 42));
+  Local<Object> rawOutput = New<Object>();
+  Set(rawOutput, attrFile, unsupported);
+  Set(rawOutput, attrBuffer, hasOutputBufferRaw);
+  Set(rawOutput, attrStream, hasOutputBufferRaw);
+  Set(raw, attrOutput, rawOutput);
+
+  info.GetReturnValue().Set(format);
+}
+
+/*
+  Synchronous, internal-only method used by some of the functional tests.
+  Calculates the maximum colour distance using the DE2000 algorithm
+  between two images of the same dimensions and number of channels.
+*/
+NAN_METHOD(_maxColourDistance) {
+  using sharp::Premultiply;
+  using sharp::DetermineImageType;
+  using sharp::ImageType;
+  using sharp::InitImage;
+  using sharp::HasAlpha;
+
+  HandleScope();
+
+  // Create "hook" VipsObject to hang image references from
+  VipsObject *hook = reinterpret_cast<VipsObject*>(vips_image_new());
+
+  // Open input files
+  VipsImage *image1 = NULL;
+  ImageType imageType1 = DetermineImageType(*Utf8String(info[0]));
+  if (imageType1 != ImageType::UNKNOWN) {
+    image1 = InitImage(*Utf8String(info[0]), VIPS_ACCESS_SEQUENTIAL);
+    if (image1 == NULL) {
+      g_object_unref(hook);
+      return ThrowError("Input file 1 has corrupt header");
+    } else {
+      vips_object_local(hook, image1);
+    }
+  } else {
+    g_object_unref(hook);
+    return ThrowError("Input file 1 is of an unsupported image format");
+  }
+  VipsImage *image2 = NULL;
+  ImageType imageType2 = DetermineImageType(*Utf8String(info[1]));
+  if (imageType2 != ImageType::UNKNOWN) {
+    image2 = InitImage(*Utf8String(info[1]), VIPS_ACCESS_SEQUENTIAL);
+    if (image2 == NULL) {
+      g_object_unref(hook);
+      return ThrowError("Input file 2 has corrupt header");
+    } else {
+      vips_object_local(hook, image2);
+    }
+  } else {
+    g_object_unref(hook);
+    return ThrowError("Input file 2 is of an unsupported image format");
+  }
+
+  // Ensure same number of channels
+  if (image1->Bands != image2->Bands) {
+    g_object_unref(hook);
+    return ThrowError("mismatchedBands");
+  }
+  // Ensure same dimensions
+  if (image1->Xsize != image2->Xsize || image1->Ysize != image2->Ysize) {
+    g_object_unref(hook);
+    return ThrowError("mismatchedDimensions");
+  }
+
+  // Premultiply and remove alpha
+  if (HasAlpha(image1)) {
+    VipsImage *imagePremultiplied1;
+    if (Premultiply(hook, image1, &imagePremultiplied1)) {
+      g_object_unref(hook);
+      return ThrowError(vips_error_buffer());
+    }
+    vips_object_local(hook, imagePremultiplied1);
+    VipsImage *imagePremultipliedNoAlpha1;
+    if (vips_extract_band(image1, &imagePremultipliedNoAlpha1, 1, "n", image1->Bands - 1, NULL)) {
+      g_object_unref(hook);
+      return ThrowError(vips_error_buffer());
+    }
+    vips_object_local(hook, imagePremultipliedNoAlpha1);
+    image1 = imagePremultipliedNoAlpha1;
+  }
+  if (HasAlpha(image2)) {
+    VipsImage *imagePremultiplied2;
+    if (Premultiply(hook, image2, &imagePremultiplied2)) {
+      g_object_unref(hook);
+      return ThrowError(vips_error_buffer());
+    }
+    vips_object_local(hook, imagePremultiplied2);
+    VipsImage *imagePremultipliedNoAlpha2;
+    if (vips_extract_band(image2, &imagePremultipliedNoAlpha2, 1, "n", image2->Bands - 1, NULL)) {
+      g_object_unref(hook);
+      return ThrowError(vips_error_buffer());
+    }
+    vips_object_local(hook, imagePremultipliedNoAlpha2);
+    image2 = imagePremultipliedNoAlpha2;
+  }
+  // Calculate colour distance
+  VipsImage *difference;
+  if (vips_dE00(image1, image2, &difference, NULL)) {
+    g_object_unref(hook);
+    return ThrowError(vips_error_buffer());
+  }
+  vips_object_local(hook, difference);
+  // Extract maximum distance
+  double maxColourDistance;
+  if (vips_max(difference, &maxColourDistance, NULL)) {
+    g_object_unref(hook);
+    return ThrowError(vips_error_buffer());
+  }
+  g_object_unref(hook);
+  info.GetReturnValue().Set(New<Number>(maxColourDistance));
 }

src/utilities.h

@@ -7,5 +7,7 @@ NAN_METHOD(cache);
 NAN_METHOD(concurrency);
 NAN_METHOD(counters);
 NAN_METHOD(libvipsVersion);
+NAN_METHOD(format);
+NAN_METHOD(_maxColourDistance);
 
 #endif  // SRC_UTILITIES_H_

test/bench/package.json

@@ -9,13 +9,14 @@
   },
   "devDependencies": {
     "imagemagick": "^0.1.3",
-    "imagemagick-native": "^1.7.0",
-    "gm": "^1.17.0",
-    "async": "^0.9.0",
-    "semver": "^4.3.0",
+    "imagemagick-native": "^1.8.0",
+    "gm": "^1.18.1",
+    "lwip": "^0.0.7",
+    "async": "^1.4.2",
+    "semver": "^5.0.1",
     "benchmark": "^1.0.0"
   },
-  "license": "Apache 2.0",
+  "license": "Apache-2.0",
   "engines": {
     "node": ">=0.10"
   }

test/bench/perf.js

@@ -7,10 +7,22 @@ var assert = require('assert');
 var Benchmark = require('benchmark');
 var semver = require('semver');
 
-var imagemagick = require('imagemagick');
-var imagemagickNative = require('imagemagick-native');
+// Contenders
 var gm = require('gm');
+var imagemagick = require('imagemagick');
 var sharp = require('../../index');
+var imagemagickNative;
+try {
+  imagemagickNative = require('imagemagick-native');
+} catch (err) {
+  console.log('Excluding imagemagick-native');
+}
+var lwip;
+try {
+  lwip = require('lwip');
+} catch (err) {
+  console.log('Excluding lwip');
+}
 
 var fixtures = require('../fixtures');
 
@@ -26,7 +38,54 @@ sharp.cache(0);
 async.series({
   jpeg: function(callback) {
     var inputJpgBuffer = fs.readFileSync(fixtures.inputJpg);
-    (new Benchmark.Suite('jpeg')).add('imagemagick-file-file', {
+    var jpegSuite = new Benchmark.Suite('jpeg');
+    // 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, 'linear', function (err, image) {
+              if (err) {
+                throw err;
+              }
+              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, 'linear', function (err, image) {
+              if (err) {
+                throw err;
+              }
+              image.toBuffer('jpg', {quality: 80}, function (err, buffer) {
+                if (err) {
+                  throw err;
+                }
+                assert.notStrictEqual(null, buffer);
+                deferred.resolve();
+              });
+            });
+          });
+        }
+      });
+    }
+    // imagemagick
+    jpegSuite.add('imagemagick-file-file', {
       defer: true,
       fn: function(deferred) {
         imagemagick.resize({
@@ -45,26 +104,32 @@ async.series({
           }
         });
       }
-    }).add('imagemagick-native-buffer-buffer', {
-      defer: true,
-      fn: function(deferred) {
-        imagemagickNative.convert({
-          srcData: inputJpgBuffer,
-          quality: 80,
-          width: width,
-          height: height,
-          format: 'JPEG',
-          filter: magickFilter
-        }, function (err, buffer) {
-          if (err) {
-            throw err;
-          } else {
-            assert.notStrictEqual(null, buffer);
-            deferred.resolve();
-          }
-        });
-      }
-    }).add('gm-buffer-file', {
+    });
+    // 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: magickFilter
+          }, function (err, buffer) {
+            if (err) {
+              throw err;
+            } else {
+              assert.notStrictEqual(null, buffer);
+              deferred.resolve();
+            }
+          });
+        }
+      });
+    }
+    // gm
+    jpegSuite.add('gm-buffer-file', {
       defer: true,
       fn: function(deferred) {
         gm(inputJpgBuffer)
@@ -126,7 +191,9 @@ async.series({
             }
           });
       }
-    }).add('sharp-buffer-file', {
+    });
+    // sharp
+    jpegSuite.add('sharp-buffer-file', {
       defer: true,
       fn: function(deferred) {
         sharp(inputJpgBuffer).resize(width, height).toFile(fixtures.outputJpg, function(err) {
@@ -311,6 +378,18 @@ async.series({
           }
         });
       }
+    }).add('sharp-normalise', {
+      defer: true,
+      fn: function(deferred) {
+        sharp(inputJpgBuffer).resize(width, height).normalise().toBuffer(function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            deferred.resolve();
+          }
+        });
+      }
     }).add('sharp-greyscale', {
       defer: true,
       fn: function(deferred) {
@@ -392,6 +471,32 @@ async.series({
   png: function(callback) {
     var inputPngBuffer = fs.readFileSync(fixtures.inputPng);
     var pngSuite = new Benchmark.Suite('png');
+    // 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, 'linear', function (err, image) {
+              if (err) {
+                throw err;
+              }
+              image.toBuffer('png', function (err, buffer) {
+                if (err) {
+                  throw err;
+                }
+                assert.notStrictEqual(null, buffer);
+                deferred.resolve();
+              });
+            });
+          });
+        }
+      });
+    }
+    // imagemagick
     pngSuite.add('imagemagick-file-file', {
       defer: true,
       fn: function(deferred) {
@@ -400,7 +505,6 @@ async.series({
           dstPath: fixtures.outputPng,
           width: width,
           height: height,
-          format: 'jpg',
           filter: magickFilter
         }, function(err) {
           if (err) {
@@ -410,19 +514,25 @@ async.series({
           }
         });
       }
-    }).add('imagemagick-native-buffer-buffer', {
-      defer: true,
-      fn: function(deferred) {
-        imagemagickNative.convert({
-          srcData: inputPngBuffer,
-          width: width,
-          height: height,
-          format: 'PNG',
-          filter: magickFilter
-        });
-        deferred.resolve();
-      }
-    }).add('gm-file-file', {
+    });
+    // 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: magickFilter
+          });
+          deferred.resolve();
+        }
+      });
+    }
+    // gm
+    pngSuite.add('gm-file-file', {
       defer: true,
       fn: function(deferred) {
         gm(fixtures.inputPng)
@@ -451,7 +561,9 @@ async.series({
             }
           });
       }
-    }).add('sharp-buffer-file', {
+    });
+    // sharp
+    pngSuite.add('sharp-buffer-file', {
       defer: true,
       fn: function(deferred) {
         sharp(inputPngBuffer).resize(width, height).toFile(fixtures.outputPng, function(err) {

test/fixtures/index.js

@@ -1,11 +1,43 @@
 'use strict';
 
 var path = require('path');
+var assert = require('assert');
+var sharp = require('../../index');
+var maxColourDistance = require('../../build/Release/sharp')._maxColourDistance;
 
+// Helpers
 var getPath = function(filename) {
   return path.join(__dirname, filename);
 };
 
+// Generates a 64-bit-as-binary-string image fingerprint
+// Based on the dHash gradient method - see http://www.hackerfactor.com/blog/index.php?/archives/529-Kind-of-Like-That.html
+var fingerprint = function(image, callback) {
+  sharp(image)
+    .greyscale()
+    .normalise()
+    .resize(9, 8)
+    .ignoreAspectRatio()
+    .interpolateWith(sharp.interpolator.vertexSplitQuadraticBasisSpline)
+    .raw()
+    .toBuffer(function(err, data) {
+      if (err) {
+        callback(err);
+      } else {
+        var fingerprint = '';
+        for (var col = 0; col < 8; col++) {
+          var gradient = 0;
+          for (var row = 0; row < 8; row++) {
+            var left = data[row * 8 + col];
+            var right = data[row * 8 + col + 1];
+            fingerprint = fingerprint + (left < right ? '1' : '0');
+          }
+        }
+        callback(null, fingerprint);
+      }
+    });
+};
+
 module.exports = {
 
   inputJpg: getPath('2569067123_aca715a2ee_o.jpg'), // http://www.flickr.com/photos/grizdave/2569067123/
@@ -15,21 +47,102 @@ module.exports = {
   inputJpgWithCmykProfile: getPath('Channel_digital_image_CMYK_color.jpg'), // http://en.wikipedia.org/wiki/File:Channel_digital_image_CMYK_color.jpg
   inputJpgWithCmykNoProfile: getPath('Channel_digital_image_CMYK_color_no_profile.jpg'),
   inputJpgWithCorruptHeader: getPath('corrupt-header.jpg'),
+  inputJpgWithLowContrast: getPath('low-contrast.jpg'), // http://www.flickr.com/photos/grizdave/2569067123/
 
   inputPng: getPath('50020484-00001.png'), // http://c.searspartsdirect.com/lis_png/PLDM/50020484-00001.png
   inputPngWithTransparency: getPath('blackbug.png'), // public domain
+  inputPngWithGreyAlpha: getPath('grey-8bit-alpha.png'),
+  inputPngWithOneColor: getPath('2x2_fdcce6.png'),
+  inputPngOverlayLayer0: getPath('alpha-layer-0-background.png'),
+  inputPngOverlayLayer1: getPath('alpha-layer-1-fill.png'),
+  inputPngOverlayLayer2: getPath('alpha-layer-2-ink.png'),
+  inputPngOverlayLayer1LowAlpha: getPath('alpha-layer-1-fill-low-alpha.png'),
+  inputPngOverlayLayer2LowAlpha: getPath('alpha-layer-2-ink-low-alpha.png'),
+  inputPngAlphaPremultiplicationSmall: getPath('alpha-premultiply-1024x768-paper.png'),
+  inputPngAlphaPremultiplicationLarge: getPath('alpha-premultiply-2048x1536-paper.png'),
 
   inputWebP: getPath('4.webp'), // http://www.gstatic.com/webp/gallery/4.webp
+  inputWebPWithTransparency: getPath('5_webp_a.webp'), // http://www.gstatic.com/webp/gallery3/5_webp_a.webp
   inputTiff: getPath('G31D.TIF'), // http://www.fileformat.info/format/tiff/sample/e6c9a6e5253348f4aef6d17b534360ab/index.htm
   inputGif: getPath('Crash_test.gif'), // http://upload.wikimedia.org/wikipedia/commons/e/e3/Crash_test.gif
   inputSvg: getPath('Wikimedia-logo.svg'), // http://commons.wikimedia.org/wiki/File:Wikimedia-logo.svg
   inputPsd: getPath('free-gearhead-pack.psd'), // https://dribbble.com/shots/1624241-Free-Gearhead-Vector-Pack
 
+  inputSvs: getPath('CMU-1-Small-Region.svs'), // http://openslide.cs.cmu.edu/download/openslide-testdata/Aperio/CMU-1-Small-Region.svs
+
   outputJpg: getPath('output.jpg'),
   outputPng: getPath('output.png'),
   outputWebP: getPath('output.webp'),
   outputZoinks: getPath('output.zoinks'), // an 'unknown' file extension
 
-  path: getPath // allows tests to write files to fixtures directory (for testing with human eyes)
+  // Path for tests requiring human inspection
+  path: getPath,
+
+  // Path for expected output images
+  expected: function(filename) {
+    return getPath(path.join('expected', filename));
+  },
+
+  // Verify similarity of expected vs actual images via fingerprint
+  // Specify distance threshold using `options={threshold: 42}`, default
+  // `threshold` is 5;
+  assertSimilar: function(expectedImage, actualImage, options, callback) {
+    if (typeof options === 'function') {
+      callback = options;
+      options = {};
+    }
+
+    if (typeof options === 'undefined' && options === null) {
+      options = {};
+    }
+
+    if (options.threshold === null || typeof options.threshold === 'undefined') {
+      options.threshold = 5; // ~7% threshold
+    }
+
+    if (typeof options.threshold !== 'number') {
+      throw new TypeError('`options.threshold` must be a number');
+    }
+
+    if (typeof callback !== 'function') {
+      throw new TypeError('`callback` must be a function');
+    }
+
+    fingerprint(expectedImage, function(err, expectedFingerprint) {
+      if (err) return callback(err);
+      fingerprint(actualImage, function(err, actualFingerprint) {
+        if (err) return callback(err);
+        var distance = 0;
+        for (var i = 0; i < 64; i++) {
+          if (expectedFingerprint[i] !== actualFingerprint[i]) {
+            distance++;
+          }
+        }
+
+        if (distance > options.threshold) {
+          return callback(new Error('Expected maximum similarity distance: ' + options.threshold + '. Actual: ' + distance + '.'));
+        }
+
+        callback();
+      });
+    });
+  },
+
+  assertMaxColourDistance: function(actualImagePath, expectedImagePath, acceptedDistance) {
+    if (typeof actualImagePath !== 'string') {
+      throw new TypeError('`actualImagePath` must be a string; got ' + actualImagePath);
+    }
+    if (typeof expectedImagePath !== 'string') {
+      throw new TypeError('`expectedImagePath` must be a string; got ' + expectedImagePath);
+    }
+    if (typeof acceptedDistance !== 'number') {
+      // Default threshold
+      acceptedDistance = 1;
+    }
+    var distance = maxColourDistance(actualImagePath, expectedImagePath);
+    if (distance > acceptedDistance) {
+      throw new Error('Expected maximum absolute distance of ' + acceptedDistance + ', actual ' + distance);
+    }
+  }
 
 };

test/leak/leak.sh

@@ -1,8 +1,18 @@
+#!/bin/sh
+
 if ! type valgrind >/dev/null; then
   echo "Please install valgrind before running memory leak tests"
   exit 1
 fi
 
-curl -O https://raw.githubusercontent.com/jcupitt/libvips/master/libvips.supp test/leak/libvips.supp
-cd ../../
-G_SLICE=always-malloc G_DEBUG=gc-friendly valgrind --suppressions=test/leak/libvips.supp --suppressions=test/leak/sharp.supp --leak-check=full --show-leak-kinds=definite,indirect,possible --num-callers=20 --trace-children=yes npm test
+curl -o ./test/leak/libvips.supp https://raw.githubusercontent.com/jcupitt/libvips/master/libvips.supp
+
+G_SLICE=always-malloc G_DEBUG=gc-friendly valgrind \
+  --suppressions=test/leak/libvips.supp \
+  --suppressions=test/leak/sharp.supp \
+  --gen-suppressions=yes \
+  --leak-check=full \
+  --show-leak-kinds=definite,indirect,possible \
+  --num-callers=20 \
+  --trace-children=yes \
+  npm test

test/leak/sharp.supp

@@ -30,7 +30,61 @@
   fun:jpeg_finish_compress
 }
 
-# libvips interpolator warnings
+# libpng
+{
+  cond_libpng_png_read_row
+  Memcheck:Cond
+  ...
+  fun:png_read_row
+}
+{
+  value_libpng_png_read_row
+  Memcheck:Value8
+  ...
+  fun:png_read_row
+}
+{
+  cond_libpng_png_write_rows
+  Memcheck:Cond
+  ...
+  fun:png_write_row
+  fun:png_write_rows
+}
+{
+  value_libpng_png_write_rows
+  Memcheck:Value8
+  ...
+  fun:png_write_row
+  fun:png_write_rows
+}
+
+# libwebp
+{
+  cond_libwebp_WebPEncodeRGBA
+  Memcheck:Cond
+  ...
+  fun:WebPEncodeRGBA
+}
+{
+  value_libwebp_WebPEncodeRGBA
+  Memcheck:Value8
+  ...
+  fun:WebPEncodeRGBA
+}
+{
+  cond_libwebp_WebPEncodeRGB
+  Memcheck:Cond
+  ...
+  fun:WebPEncodeRGB
+}
+{
+  value_libwebp_WebPEncodeRGB
+  Memcheck:Value8
+  ...
+  fun:WebPEncodeRGB
+}
+
+# libvips
 {
   cond_libvips_interpolate_lbb
   Memcheck:Cond
@@ -38,6 +92,18 @@
   fun:_ZL32vips_interpolate_lbb_interpolateP16_VipsInterpolatePvP11_VipsRegiondd
   fun:vips_affine_gen
 }
+{
+  cond_libvips_conv_gen
+  Memcheck:Cond
+  fun:conv_gen
+  fun:vips_region_generate
+}
+{
+  cond_libvips_col_sRGB2scRGB_8
+  Memcheck:Value8
+  fun:vips_col_sRGB2scRGB_8
+  fun:vips_sRGB2scRGB_gen
+}
 
 # libuv warnings
 {
@@ -46,6 +112,19 @@
   ...
   fun:uv__work_done
 }
+{
+  param_libuv_fs_work
+  Memcheck:Param
+  write(buf)
+  ...
+  fun:uv__fs_work
+}
+{
+  cond_libuv_work_done
+  Memcheck:Cond
+  ...
+  fun:uv__work_done
+}
 
 # nodejs warnings
 {
@@ -55,6 +134,13 @@
   ...
   obj:/usr/bin/nodejs
 }
+{
+  param_iojs_write_buffer
+  Memcheck:Param
+  write(buf)
+  ...
+  obj:/usr/bin/iojs
+}
 {
   leak_nodejs_ImmutableAsciiSource_CreateFromLiteral
   Memcheck:Leak
@@ -99,6 +185,69 @@
   ...
   fun:ares_init_options
 }
+{
+  leak_nodejs_CreateEnvironment_Handle
+  Memcheck:Leak
+  match-leak-kinds: possible
+  ...
+  fun:_ZN4node17CreateEnvironmentEPN2v87IsolateEP9uv_loop_sNS0_6HandleINS0_7ContextEEEiPKPKciSB_
+}
+{
+  leak_nodejs_CreateEnvironment_Local
+  Memcheck:Leak
+  match-leak-kinds: possible
+  ...
+  fun:_ZN4node17CreateEnvironmentEPN2v87IsolateEP9uv_loop_sNS0_5LocalINS0_7ContextEEEiPKPKciSB_
+}
+{
+  leak_nan_FunctionCallbackInfo
+  Memcheck:Leak
+  match-leak-kinds: definite
+  ...
+  fun:_ZN3Nan3impL23FunctionCallbackWrapperERKN2v820FunctionCallbackInfoINS1_5ValueEEE
+}
+{
+  leak_v8_FunctionCallbackInfo
+  Memcheck:Leak
+  match-leak-kinds: possible
+  ...
+  fun:_ZN2v88internal25FunctionCallbackArguments4CallEPFvRKNS_20FunctionCallbackInfoINS_5ValueEEEE
+}
+{
+  leak_v8_CallInterfaceDescriptorData
+  Memcheck:Leak
+  match-leak-kinds: possible
+  ...
+  fun:_ZN2v88internal27CallInterfaceDescriptorData10InitializeEiPNS0_8RegisterEPNS0_14RepresentationEPNS0_27PlatformInterfaceDescriptorE
+}
+{
+  leak_v8_Isolate_Init
+  Memcheck:Leak
+  match-leak-kinds: possible
+  ...
+  fun:_ZN2v88internal7Isolate4InitEPNS0_12DeserializerE
+}
+{
+  leak_v8_StoreDescriptor_Initialize
+  Memcheck:Leak
+  match-leak-kinds: possible
+  ...
+  fun:_ZN2v88internal15StoreDescriptor10InitializeEPNS0_27CallInterfaceDescriptorDataE
+}
+{
+  leak_v8_CodeStub_GetCode
+  Memcheck:Leak
+  match-leak-kinds: possible
+  ...
+  fun:_ZN2v88internal8CodeStub7GetCodeEv
+}
+{
+  leak_v8_CreateICUCollator
+  Memcheck:Leak
+  match-leak-kinds: possible
+  ...
+  fun:_ZN2v88internal12_GLOBAL__N_117CreateICUCollatorEPNS0_7IsolateERKN6icu_556LocaleENS0_6HandleINS0_8JSObjectEEE
+}
 
 # vips__init warnings
 {
@@ -109,3 +258,35 @@
   ...
   fun:vips__init
 }
+
+# *magick warnings
+{
+  leak_magick_read
+  Memcheck:Leak
+  match-leak-kinds: definite,indirect,possible
+  ...
+  fun:ReadImage
+  ...
+  fun:vips__magick_read
+}
+{
+  leak_magick_read_header
+  Memcheck:Leak
+  match-leak-kinds: definite,indirect,possible
+  ...
+  fun:ReadImage
+  ...
+  fun:vips__magick_read_header
+}
+
+# glib g_file_read_link
+# https://github.com/GNOME/glib/commit/49a5d0f6f2aed99cd78f25655f137f4448e47d92
+{
+  leak_magick
+  Memcheck:Leak
+  match-leak-kinds: definite,indirect,possible
+  ...
+  fun:g_file_read_link
+  ...
+  fun:vips_gsf_path
+}

test/unit/alpha.js

@@ -1,9 +1,8 @@
 'use strict';
 
 var assert = require('assert');
-
-var sharp = require('../../index');
 var fixtures = require('../fixtures');
+var sharp = require('../../index');
 
 sharp.cache(0);
 
@@ -13,7 +12,12 @@ describe('Alpha transparency', function() {
     sharp(fixtures.inputPngWithTransparency)
       .flatten()
       .resize(400, 300)
-      .toFile(fixtures.path('output.flatten-black.jpg'), done);
+      .toBuffer(function(err, data, info) {
+        if (err) throw err;
+        assert.strictEqual(400, info.width);
+        assert.strictEqual(300, info.height);
+        fixtures.assertSimilar(fixtures.expected('flatten-black.jpg'), data, done);
+      });
   });
 
   it('Flatten to RGB orange', function(done) {
@@ -21,7 +25,12 @@ describe('Alpha transparency', function() {
       .flatten()
       .background({r: 255, g: 102, b: 0})
       .resize(400, 300)
-      .toFile(fixtures.path('output.flatten-rgb-orange.jpg'), done);
+      .toBuffer(function(err, data, info) {
+        if (err) throw err;
+        assert.strictEqual(400, info.width);
+        assert.strictEqual(300, info.height);
+        fixtures.assertSimilar(fixtures.expected('flatten-orange.jpg'), data, done);
+      });
   });
 
   it('Flatten to CSS/hex orange', function(done) {
@@ -29,7 +38,12 @@ describe('Alpha transparency', function() {
       .flatten()
       .background('#ff6600')
       .resize(400, 300)
-      .toFile(fixtures.path('output.flatten-hex-orange.jpg'), done);
+      .toBuffer(function(err, data, info) {
+        if (err) throw err;
+        assert.strictEqual(400, info.width);
+        assert.strictEqual(300, info.height);
+        fixtures.assertSimilar(fixtures.expected('flatten-orange.jpg'), data, done);
+      });
   });
 
   it('Do not flatten', function(done) {
@@ -61,4 +75,38 @@ describe('Alpha transparency', function() {
       });
   });
 
+  it('Enlargement with non-nearest neighbor interpolation shouldn’t cause dark edges', function(done) {
+    var BASE_NAME = 'alpha-premultiply-enlargement-2048x1536-paper.png';
+    var actual = fixtures.path('output.' + BASE_NAME);
+    var expected = fixtures.expected(BASE_NAME);
+    sharp(fixtures.inputPngAlphaPremultiplicationSmall)
+      .resize(2048, 1536)
+      .interpolateWith('bicubic')
+      .toFile(actual, function(err) {
+        if (err) {
+          done(err);
+        } else {
+          fixtures.assertMaxColourDistance(actual, expected, 102);
+          done();
+        }
+      });
+  });
+
+  it('Reduction with non-nearest neighbor interpolation shouldn’t cause dark edges', function(done) {
+    var BASE_NAME = 'alpha-premultiply-reduction-1024x768-paper.png';
+    var actual = fixtures.path('output.' + BASE_NAME);
+    var expected = fixtures.expected(BASE_NAME);
+    sharp(fixtures.inputPngAlphaPremultiplicationLarge)
+      .resize(1024, 768)
+      .interpolateWith('bicubic')
+      .toFile(actual, function(err) {
+        if (err) {
+          done(err);
+        } else {
+          fixtures.assertMaxColourDistance(actual, expected, 102);
+          done();
+        }
+      });
+  });
+
 });

test/unit/blur.js

@@ -13,12 +13,11 @@ describe('Blur', function() {
     sharp(fixtures.inputJpg)
       .resize(320, 240)
       .blur(1)
-      .toFile(fixtures.path('output.blur-1.jpg'), function(err, info) {
-        if (err) throw err;
+      .toBuffer(function(err, data, info) {
         assert.strictEqual('jpeg', info.format);
         assert.strictEqual(320, info.width);
         assert.strictEqual(240, info.height);
-        done();
+        fixtures.assertSimilar(fixtures.expected('blur-1.jpg'), data, done);
       });
   });
 
@@ -26,12 +25,11 @@ describe('Blur', function() {
     sharp(fixtures.inputJpg)
       .resize(320, 240)
       .blur(10)
-      .toFile(fixtures.path('output.blur-10.jpg'), function(err, info) {
-        if (err) throw err;
+      .toBuffer(function(err, data, info) {
         assert.strictEqual('jpeg', info.format);
         assert.strictEqual(320, info.width);
         assert.strictEqual(240, info.height);
-        done();
+        fixtures.assertSimilar(fixtures.expected('blur-10.jpg'), data, done);
       });
   });
 
@@ -39,12 +37,11 @@ describe('Blur', function() {
     sharp(fixtures.inputJpg)
       .resize(320, 240)
       .blur(0.3)
-      .toFile(fixtures.path('output.blur-0.3.jpg'), function(err, info) {
-        if (err) throw err;
+      .toBuffer(function(err, data, info) {
         assert.strictEqual('jpeg', info.format);
         assert.strictEqual(320, info.width);
         assert.strictEqual(240, info.height);
-        done();
+        fixtures.assertSimilar(fixtures.expected('blur-0.3.jpg'), data, done);
       });
   });
 
@@ -52,24 +49,18 @@ describe('Blur', function() {
     sharp(fixtures.inputJpg)
       .resize(320, 240)
       .blur()
-      .toFile(fixtures.path('output.blur-mild.jpg'), function(err, info) {
-        if (err) throw err;
+      .toBuffer(function(err, data, info) {
         assert.strictEqual('jpeg', info.format);
         assert.strictEqual(320, info.width);
         assert.strictEqual(240, info.height);
-        done();
+        fixtures.assertSimilar(fixtures.expected('blur-mild.jpg'), data, done);
       });
   });
 
-  it('invalid radius', function(done) {
-    var isValid = true;
-    try {
+  it('invalid radius', function() {
+    assert.throws(function() {
       sharp(fixtures.inputJpg).blur(0.1);
-    } catch (err) {
-      isValid = false;
-    }
-    assert.strictEqual(false, isValid);
-    done();
+    });
   });
 
   it('blurred image is smaller than non-blurred', function(done) {
@@ -77,7 +68,6 @@ describe('Blur', function() {
       .resize(320, 240)
       .blur(false)
       .toBuffer(function(err, notBlurred, info) {
-        if (err) throw err;
         assert.strictEqual(true, notBlurred.length > 0);
         assert.strictEqual('jpeg', info.format);
         assert.strictEqual(320, info.width);
@@ -86,7 +76,6 @@ describe('Blur', function() {
           .resize(320, 240)
           .blur(true)
           .toBuffer(function(err, blurred, info) {
-            if (err) throw err;
             assert.strictEqual(true, blurred.length > 0);
             assert.strictEqual(true, blurred.length < notBlurred.length);
             assert.strictEqual('jpeg', info.format);

test/unit/clone.js

@@ -0,0 +1,58 @@
+'use strict';
+
+var fs = require('fs');
+var assert = require('assert');
+
+var sharp = require('../../index');
+var fixtures = require('../fixtures');
+
+sharp.cache(0);
+
+describe('Clone', function() {
+  it('Read from Stream and write to multiple Streams', function(done) {
+    var finishEventsExpected = 2;
+    // Output stream 1
+    var output1 = fixtures.path('output.multi-stream.1.jpg');
+    var writable1 = fs.createWriteStream(output1);
+    writable1.on('finish', function() {
+      sharp(output1).toBuffer(function(err, data, info) {
+        if (err) throw err;
+        assert.strictEqual(true, data.length > 0);
+        assert.strictEqual(data.length, info.size);
+        assert.strictEqual('jpeg', info.format);
+        assert.strictEqual(320, info.width);
+        assert.strictEqual(240, info.height);
+        fs.unlinkSync(output1);
+        finishEventsExpected--;
+        if (finishEventsExpected === 0) {
+          done();
+        }
+      });
+    });
+    // Output stream 2
+    var output2 = fixtures.path('output.multi-stream.2.jpg');
+    var writable2 = fs.createWriteStream(output2);
+    writable2.on('finish', function() {
+      sharp(output2).toBuffer(function(err, data, info) {
+        if (err) throw err;
+        assert.strictEqual(true, data.length > 0);
+        assert.strictEqual(data.length, info.size);
+        assert.strictEqual('jpeg', info.format);
+        assert.strictEqual(100, info.width);
+        assert.strictEqual(122, info.height);
+        fs.unlinkSync(output2);
+        finishEventsExpected--;
+        if (finishEventsExpected === 0) {
+          done();
+        }
+      });
+    });
+    // Create parent instance
+    var rotator = sharp().rotate(90);
+    // Cloned instances with differing dimensions
+    rotator.clone().resize(320, 240).pipe(writable1);
+    rotator.clone().resize(100).pipe(writable2);
+    // Go
+    fs.createReadStream(fixtures.inputJpg).pipe(rotator);
+  });
+});