Code lint of new features

Add support for stand-alone, pre-resize, and post-resize extraction

.gitignore

@@ -13,3 +13,7 @@ results
 build
 node_modules
 tests/fixtures/output.*
+tests/libvips.supp
+
+# Mac OS X
+.DS_Store

.travis.yml

@@ -5,12 +5,12 @@ node_js:
 before_install:
   - sudo add-apt-repository ppa:lyrasis/precise-backports -y
   - sudo apt-get update -qq
-  - sudo apt-get install -qq automake gobject-introspection gtk-doc-tools libfftw3-dev libglib2.0-dev libjpeg-turbo8-dev libpng12-dev libwebp-dev libtiff4-dev libexif-dev libxml2-dev swig graphicsmagick libmagick++-dev
+  - sudo apt-get install -qq automake gobject-introspection gtk-doc-tools libglib2.0-dev libjpeg-turbo8-dev libpng12-dev libwebp-dev libtiff4-dev libexif-dev libxml2-dev swig graphicsmagick libmagick++-dev
   - git clone https://github.com/jcupitt/libvips.git
   - cd libvips
   - git checkout 7.38
   - ./bootstrap.sh
-  - ./configure --enable-debug=no --enable-cxx=yes --without-orc --without-python
+  - ./configure --enable-debug=no --enable-cxx=yes --without-orc --without-python --without-fftw
   - make
   - sudo make install
   - sudo ldconfig

README.md

@@ -5,19 +5,22 @@
 * [API](https://github.com/lovell/sharp#api)
 * [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.
 
-The performance of JPEG resizing is typically 8x faster than ImageMagick and GraphicsMagick, based mainly on the number of CPU cores available. Everything remains non-blocking thanks to _libuv_ and Promises/A+ are supported.
+The performance of JPEG resizing is typically 8x faster than ImageMagick and GraphicsMagick, based mainly on the number of CPU cores available.
 
-This module supports reading and writing images of JPEG, PNG and WebP to and from both Buffer objects and the filesystem. It also supports reading images of many other types from the filesystem via libmagick++ or libgraphicsmagick++ if present.
+Memory usage is kept to a minimum, no child processes are spawned, everything remains non-blocking thanks to _libuv_ and Promises/A+ are supported.
+
+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.
 
 When generating JPEG output all metadata is removed and Huffman tables optimised without having to use separate command line tools like [jpegoptim](https://github.com/tjko/jpegoptim) and [jpegtran](http://jpegclub.org/jpegtran/).
 
 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.
+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
 
@@ -34,39 +37,62 @@ _libvips_ can take advantage of [liborc](http://code.entropywave.com/orc/) if pr
 
 	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
 
-### Install libvips on Ubuntu Linux
+### Install libvips on Linux
 
-#### Ubuntu 14.x
+#### Ubuntu 14.04 LTS
 
 	sudo apt-get install libvips-dev
 
-#### Ubuntu 13.x
+#### Ubuntu 12.04 LTS
 
-Compiling from source is recommended:
-
-	sudo apt-get install automake build-essential git gobject-introspection gtk-doc-tools libfftw3-dev libglib2.0-dev libjpeg-turbo8-dev libpng12-dev libwebp-dev libtiff5-dev libexif-dev libxml2-dev swig
+	sudo add-apt-repository -y ppa:lyrasis/precise-backports
+	sudo apt-get update
+	sudo apt-get install -y automake build-essential git gobject-introspection gtk-doc-tools libglib2.0-dev libjpeg-turbo8-dev libpng12-dev libwebp-dev libtiff4-dev libexif-dev libxml2-dev swig libmagickwand-dev
 	git clone https://github.com/jcupitt/libvips.git
 	cd libvips
-	git checkout 7.38
+	git checkout 7.40
 	./bootstrap.sh
-	./configure --enable-debug=no --enable-cxx=yes --without-python --without-orc
+	./configure --enable-debug=no --enable-cxx=yes --without-python --without-orc --without-fftw
 	make
 	sudo make install
 	sudo ldconfig
 
-#### Ubuntu 12.x
+#### Debian Jessie
 
-Requires `libtiff4-dev` instead of `libtiff5-dev` and has [a bug](https://bugs.launchpad.net/ubuntu/+source/libwebp/+bug/1108731) in the libwebp package. Work around these problems by running these commands first:
+	apt-get install libvips-dev
 
-	sudo add-apt-repository ppa:lyrasis/precise-backports
-	sudo apt-get update
-	sudo apt-get install libtiff4-dev
+#### Centos 6
 
-Then follow Ubuntu 13.x instructions.
+	sudo yum groupinstall -y "Development Tools"
+	sudo yum install -y gtk-doc libxml2-devel libjpeg-turbo-devel libpng-devel libtiff-devel libexif-devel ImageMagick-devel
+	sudo yum install -y http://li.nux.ro/download/nux/dextop/el6/x86_64/nux-dextop-release-0-2.el6.nux.noarch.rpm
+	sudo yum install -y --enablerepo=nux-dextop gobject-introspection-devel
+	sudo yum install -y http://rpms.famillecollet.com/enterprise/remi-release-6.rpm
+	sudo yum install -y --enablerepo=remi libwebp-devel
+	git clone https://github.com/jcupitt/libvips.git
+	cd libvips
+	git checkout 7.40
+	./bootstrap.sh
+	./configure --prefix=/usr --enable-docs=no --enable-debug=no --enable-cxx=yes --without-orc --without-python --without-fftw
+	make
+	sudo make install
+	sudo ldconfig
+
+### Install libvips on Heroku
+
+[Alessandro Tagliapietra](https://github.com/alex88) maintains an [Heroku buildpack for libvips](https://github.com/alex88/heroku-buildpack-vips) and its dependencies.
+
+### Using with gulp.js
+
+[Mohammad Prabowo](https://github.com/rizalp) maintains a [gulp.js plugin](https://github.com/rizalp/gulp-sharp).
 
 ## Usage examples
 
@@ -85,54 +111,159 @@ sharp('input.jpg').resize(300, 200).toFile('output.jpg', function(err) {
 ```
 
 ```javascript
-sharp('input.jpg').rotate().resize(null, 200).progressive().toBuffer(function(err, outputBuffer) {
-  if (err) {
-    throw err;
-  }
-  // outputBuffer contains 200px high progressive JPEG image data, auto-rotated using EXIF Orientation tag
+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(metadata.width / 2).webp().toBuffer(function(err, outputBuffer, info) {
+    // outputBuffer contains a WebP image half the width and height of the original JPEG
+  });
 });
 ```
 
 ```javascript
-sharp('input.png').rotate(180).resize(300).sharpen().quality(90).webp().then(function(outputBuffer) {
-  // outputBuffer contains 300px wide, upside down, sharpened, 90% quality WebP image data
-});
+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(inputBuffer).resize(200, 300).bicubicInterpolation().embedWhite().toFile('output.tiff').then(function() {
-  // output.tiff is a 200 pixels wide and 300 pixels high image containing a bicubic scaled
-  // version, embedded on a white canvas, of the image data in buffer
-});
+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
-sharp('input.gif').resize(200, 300).embedBlack().webp(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 black canvas, of input.gif
-});
+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(inputBuffer).resize(200, 200).max().jpeg().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
-});
+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 bicubic 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()
+  .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()
+  .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
 
-### sharp(input)
+### Input methods
 
-Constructor to which further methods are chained. `input` can be one of:
+#### sharp([input])
+
+Constructor to which further methods are chained. `input`, if present, can be one of:
 
 * Buffer containing JPEG, PNG or WebP image data, or
 * String containing the filename of an image, with most major formats supported.
 
-### resize(width, [height])
+The object returned implements the [stream.Duplex](http://nodejs.org/api/stream.html#stream_class_stream_duplex) class.
+
+JPEG, PNG or WebP 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#L502)
+* `channels`: Number of bands e.g. `3` for sRGB, `4` for CMYK
+* `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.
+
+### Image transformation options
+
+#### resize(width, [height])
 
 Scale output to `width` x `height`. By default, the resized image is cropped to the exact size specified.
 
@@ -140,155 +271,246 @@ Scale output to `width` x `height`. By default, the resized image is cropped to
 
 `height` is the Number of pixels high the resultant image should be. Use `null` or `undefined` to auto-scale the height to match the width.
 
-### crop()
+#### 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.
 
-### max()
+`gravity`, if present, is an attribute of the `sharp.gravity` Object e.g. `sharp.gravity.north`.
 
-Preserving aspect ratio, resize the image to the maximum width or height specified.
+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`.
 
-### embedWhite()
+#### background(rgba)
 
-Embed the resized image on a white background of the exact size specified.
+Set the background for the `embed` and `flatten` operations.
 
-### embedBlack()
+`rgba` is parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
 
-Embed the resized image on a black background of the exact size specified.
+The alpha value is a float between `0` (transparent) and `1` (opaque).
 
-### rotate([angle])
+The default background is `{r: 0, g: 0, b: 0, a: 1}`, black without transparency.
 
-Rotate the output image by either an explicit angle or auto-orient based on the EXIF `Orientation` tag. Mirroring is not supported.
+#### 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.
+Use this method without `angle` to determine the angle from EXIF data. Mirroring is currently unsupported.
 
-### withoutEnlargement()
+#### 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".
 
-### sharpen()
+#### sharpen()
 
-Perform a mild sharpen of the resultant image. This typically reduces performance by 30%.
+Perform a mild sharpen of the output image. This typically reduces performance by 10%.
 
-### bilinearInterpolation()
+#### interpolateWith(interpolator)
 
-Use [bilinear interpolation](http://en.wikipedia.org/wiki/Bilinear_interpolation) for image resizing, the default (and fastest) interpolation if none is specified.
+Use the given interpolator for image resizing, where `interpolator` is an attribute of the `sharp.interpolator` Object e.g. `sharp.interpolator.bicubic`.
 
-### bicubicInterpolation()
+Possible interpolators, in order of performance, are:
 
-Use [bicubic interpolation](http://en.wikipedia.org/wiki/Bicubic_interpolation) for image resizing. This typically reduces performance by 5%.
+* `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.
 
-### nohaloInterpolation()
+#### gamma([gamma])
 
-Use [Nohalo interpolation](http://eprints.soton.ac.uk/268086/) for image resizing. This typically reduces performance by a factor of 2.
+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`.
 
-### progressive()
+`gamma`, if present, is a Number betweem 1 and 3. The default value is `2.2`, a suitable approximation for sRGB images.
 
-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.
+This can improve the perceived brightness of a resized image in non-linear colour spaces.
 
-### quality(quality)
+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.
+
+#### 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.
 
-### compressionLevel(compressionLevel)
+#### 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 (ICC, EXIF, XMP) from the input image in the output image. The default behaviour is to strip all metadata.
+
+#### 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 -1 and 9.
+`compressionLevel` is a Number between 0 and 9.
 
-### sequentialRead()
+### Output methods
 
-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.
-
-### toFile(filename, [callback])
+#### 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 a single argument `(err)` containing an error message, if any.
+`callback`, if present, is called with two arguments `(err, info)` where:
+
+* `err` contains an error message, if any.
+* `info` contains the output image `format`, `width` and `height`.
 
 A Promises/A+ promise is returned when `callback` is not provided.
 
-### toBuffer([callback])
+#### toBuffer([callback])
 
-Write image data to a Buffer, the format of which will match the input image. JPEG, PNG and WebP are supported.
+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 two arguments `(err, buffer)` where `err` is an error message, if any, and `buffer` is the resultant image data.
+`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`, `width` and `height`.
 
 A Promises/A+ promise is returned when `callback` is not provided.
 
-### jpeg([callback])
+### Utility methods
 
-Write JPEG image data to a Buffer.
+#### sharp.cache([memory], [items])
 
-`callback`, if present, gets two arguments `(err, buffer)` where `err` is an error message, if any, and `buffer` is the resultant JPEG image data.
+If `memory` or `items` are provided, set the limits of _libvips'_ operation cache.
 
-A Promises/A+ promise is returned when `callback` is not provided.
-
-### png([callback])
-
-Write PNG image data to a Buffer.
-
-`callback`, if present, gets two arguments `(err, buffer)` where `err` is an error message, if any, and `buffer` is the resultant PNG image data.
-
-A Promises/A+ promise is returned when `callback` is not provided.
-
-### webp([callback])
-
-Write WebP image data to a Buffer.
-
-`callback`, if present, gets two arguments `(err, buffer)` where `err` is an error message, if any, and `buffer` is the resultant WebP image data.
-
-A Promises/A+ promise is returned when `callback` is not provided.
-
-### sharp.cache([limit])
-
-If `limit` is provided, set the (soft) limit of _libvips_ working/cache memory to this value in MB. The default value is 100.
+* `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.
 
-Warnings such as _Application transferred too many scanlines_ are a good indicator you've set this value too low.
+```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 image processing. 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 stats = sharp.cache(); // { current: 98, high: 115, limit: 100 }
-sharp.cache(200); // { current: 98, high: 115, limit: 200 }
-sharp.cache(50); // { current: 49, high: 115, limit: 50 }
+var threads = sharp.concurrency(); // 4
+sharp.concurrency(2); // 2
+sharp.concurrency(0); // 4
+```
+
+#### 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 }
 ```
 
 ## Testing
 
-[![Build Status](https://travis-ci.org/lovell/sharp.png?branch=master)](https://travis-ci.org/lovell/sharp)
+### Ubuntu 12.04
 
-	npm test
+[![Ubuntu 12.04 Build Status](https://travis-ci.org/lovell/sharp.png?branch=master)](https://travis-ci.org/lovell/sharp)
 
-Running the tests requires both ImageMagick and GraphicsMagick plus one of either libmagick++-dev or libgraphicsmagick++.
+### Centos 6.5
 
-	brew install imagemagick
-	brew install graphicsmagick
+[![Centos 6.5 Build Status](https://snap-ci.com/lovell/sharp/branch/master/build_image)](https://snap-ci.com/lovell/sharp/branch/master)
 
-	sudo apt-get install imagemagick graphicsmagick libmagick++-dev
+### It worked on my machine
+
+```
+npm test
+```
+
+Running the comparative performance tests requires _ImageMagick_ and _GraphicsMagick_.
+
+```
+brew install imagemagick
+brew install graphicsmagick
+```
+
+```
+sudo apt-get install -qq imagemagick graphicsmagick libmagick++-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
 
-* Intel Xeon [L5520](http://ark.intel.com/products/40201/Intel-Xeon-Processor-L5520-8M-Cache-2_26-GHz-5_86-GTs-Intel-QPI) 2.27GHz 8MB cache
-* Ubuntu 13.10
-* libvips 7.38.5
+* 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) - Supports Buffers only and blocks main V8 thread whilst processing.
-* [imagemagick](https://github.com/rsms/node-imagemagick) - Supports filesystem only and "has been unmaintained for a long time".
-* [gm](https://github.com/aheckmann/gm) - Fully featured wrapper around GraphicsMagick.
-* sharp - Caching within libvips disabled to ensure a fair comparison.
+* [imagemagick-native](https://github.com/mash/node-imagemagick-native) v1.2.2 - Supports Buffers only and blocks main V8 thread whilst processing.
+* [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
 
@@ -298,25 +520,43 @@ Decompress a 2725x2225 JPEG image, resize and crop to 720x480, then compress to
 
 | Module                | Input  | Output | Ops/sec | Speed-up |
 | :-------------------- | :----- | :----- | ------: | -------: |
-| imagemagick-native    | buffer | buffer |    0.97 |        1 |
-| imagemagick           | file   | file   |    2.49 |      2.6 |
-| gm                    | buffer | file   |    3.72 |      3.8 |
-| gm                    | buffer | buffer |    3.80 |      3.9 |
-| gm                    | file   | file   |    3.67 |      3.8 |
-| gm                    | file   | buffer |    3.67 |      3.8 |
-| sharp                 | buffer | file   |   13.62 |     14.0 |
-| sharp                 | buffer | buffer |   12.43 |     12.8 |
-| sharp                 | file   | file   |   13.02 |     13.4 |
-| sharp                 | file   | buffer |   11.15 |     11.5 |
-| sharp +sharpen        | file   | buffer |   10.26 |     10.6 |
-| sharp +progressive    | file   | buffer |    9.44 |      9.7 |
-| sharp +sequentialRead | file   | buffer |   11.94 |     12.3 |
+| 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 much greater performance with caching enabled (default) and using 16+ core machines.
+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)
+
+Thank you!
 
 ## Licence
 
-Copyright 2013, 2014 Lovell Fuller and Pierre Inglebert
+Copyright 2013, 2014 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.

binding.gyp

@@ -12,7 +12,12 @@
       '<!(PKG_CONFIG_PATH="<(PKG_CONFIG_PATH)" pkg-config --cflags vips glib-2.0)',
       '<!(node -e "require(\'nan\')")'
     ],
-    'cflags': ['-fexceptions', '-pedantic', '-Wall', '-O3'],
-    'cflags_cc': ['-fexceptions', '-pedantic', '-Wall', '-O3']
+    'cflags': ['-fexceptions', '-Wall', '-O3'],
+    'cflags_cc': ['-std=c++0x', '-fexceptions', '-Wall', '-O3'],
+    'xcode_settings': {
+      'OTHER_CFLAGS': ['-std=c++11', '-stdlib=libc++', '-fexceptions', '-Wall', '-O3'],
+      'OTHER_CPLUSPLUSFLAGS': ['-std=c++11', '-stdlib=libc++', '-fexceptions', '-Wall', '-O3'],
+      'MACOSX_DEPLOYMENT_TARGET': '10.7'
+    }
   }]
 }

index.js

@@ -1,54 +1,149 @@
 /*jslint node: true */
 'use strict';
 
+var util = require('util');
+var stream = require('stream');
+
+var color = require('color');
 var Promise = require('bluebird');
+
 var sharp = require('./build/Release/sharp');
 
 var Sharp = function(input) {
   if (!(this instanceof Sharp)) {
     return new Sharp(input);
   }
+  stream.Duplex.call(this);
   this.options = {
+    // input options
+    streamIn: false,
+    sequentialRead: false,
+    // resize options
+    topOffsetPre: -1,
+    leftOffsetPre: -1,
+    widthPre: -1,
+    heightPre: -1,
+    topOffsetPost: -1,
+    leftOffsetPost: -1,
+    widthPost: -1,
+    heightPost: -1,
     width: -1,
     height: -1,
     canvas: 'c',
+    gravity: 0,
     angle: 0,
     withoutEnlargement: false,
-    sharpen: false,
     interpolator: 'bilinear',
+    // operations
+    background: [0, 0, 0, 255],
+    flatten: false,
+    sharpen: false,
+    gamma: 0,
+    greyscale: false,
+    // output options
+    output: '__input',
     progressive: false,
-    sequentialRead: false,
     quality: 80,
     compressionLevel: 6,
-    output: '__jpeg'
+    streamOut: false,
+    withMetadata: false
   };
   if (typeof input === 'string') {
+    // input=file
     this.options.fileIn = input;
-  } else if (typeof input ==='object' && input instanceof Buffer) {
+  } else if (typeof input === 'object' && input instanceof Buffer) {
+    // input=buffer
     if (input.length > 0) {
       this.options.bufferIn = input;
     } else {
       throw new Error('Buffer is empty');
     }
   } else {
-    throw new Error('Unsupported input ' + typeof input);
+    // input=stream
+    this.options.streamIn = true;
   }
   return this;
 };
 module.exports = Sharp;
+util.inherits(Sharp, stream.Duplex);
 
-Sharp.prototype.crop = function() {
+/*
+  Handle incoming chunk on Writable Stream
+*/
+Sharp.prototype._write = function(chunk, encoding, callback) {
+  /*jslint unused: false */
+  if (this.options.streamIn) {
+    if (typeof chunk === 'object' || chunk instanceof Buffer) {
+      if (typeof this.options.bufferIn === 'undefined') {
+        // Create new Buffer
+        this.options.bufferIn = new Buffer(chunk.length);
+        chunk.copy(this.options.bufferIn);
+      } else {
+        // Append to existing Buffer
+        this.options.bufferIn = Buffer.concat(
+          [this.options.bufferIn, chunk],
+          this.options.bufferIn.length + chunk.length
+        );
+      }
+      callback();
+    } else {
+      callback(new Error('Non-Buffer data on Writable Stream'));
+    }
+  } else {
+    callback(new Error('Unexpected data on Writable Stream'));
+  }
+};
+
+// Crop this part of the resized image (Center/Centre, North, East, South, West)
+module.exports.gravity = {'center': 0, 'centre': 0, 'north': 1, 'east': 2, 'south': 3, 'west': 4};
+
+Sharp.prototype.crop = function(gravity) {
   this.options.canvas = 'c';
+  if (typeof gravity !== 'undefined') {
+    // Is this a supported gravity?
+    if (!Number.isNaN(gravity) && gravity >= 0 && gravity <= 4) {
+      this.options.gravity = gravity;
+    } else {
+      throw new Error('Unsupported crop gravity ' + gravity);
+    }
+  }
   return this;
 };
 
-Sharp.prototype.embedWhite = function() {
-  this.options.canvas = 'w';
+Sharp.prototype.extract = function(topOffset, leftOffset, width, height) {
+  /*jslint unused: false */
+  var suffix = this.options.width === -1 && this.options.height === -1 ? 'Pre' : 'Post';
+  var values = arguments;
+  ['topOffset', 'leftOffset', 'width', 'height'].forEach(function(name, index) {
+    this.options[name + suffix] = values[index];
+  }.bind(this));
   return this;
 };
 
-Sharp.prototype.embedBlack = function() {
-  this.options.canvas = 'b';
+/*
+  Deprecated embed* methods, to be removed in v0.8.0
+*/
+Sharp.prototype.embedWhite = util.deprecate(function() {
+  return this.background('white').embed();
+}, "embedWhite() is deprecated, use background('white').embed() instead");
+Sharp.prototype.embedBlack = util.deprecate(function() {
+  return this.background('black').embed();
+}, "embedBlack() is deprecated, use background('black').embed() instead");
+
+/*
+  Set the background colour for embed and flatten operations.
+  Delegates to the 'Color' module, which can throw an Error
+  but is liberal in what it accepts, clamping values to sensible min/max.
+*/
+Sharp.prototype.background = function(rgba) {
+  var colour = color(rgba);
+  this.options.background = colour.rgbArray();
+  this.options.background.push(colour.alpha() * 255);
+  return this;
+};
+
+Sharp.prototype.embed = function() {
+  this.options.canvas = 'e';
   return this;
 };
 
@@ -57,6 +152,11 @@ Sharp.prototype.max = function() {
   return this;
 };
 
+Sharp.prototype.flatten = function(flatten) {
+  this.options.flatten = (typeof flatten === 'boolean') ? flatten : true;
+  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
@@ -88,28 +188,45 @@ Sharp.prototype.sharpen = function(sharpen) {
 };
 
 /*
-  Use bilinear interpolation for the affine transformation (fastest, default)
+  Set the interpolator to use for the affine transformation
 */
-Sharp.prototype.bilinearInterpolation = function() {
-  this.options.interpolator = 'bilinear';
+module.exports.interpolator = {
+  nearest: 'nearest',
+  bilinear: 'bilinear',
+  bicubic: 'bicubic',
+  nohalo: 'nohalo',
+  locallyBoundedBicubic: 'lbb',
+  vertexSplitQuadraticBasisSpline: 'vsqbs'
+};
+Sharp.prototype.interpolateWith = function(interpolator) {
+  this.options.interpolator = interpolator;
   return this;
 };
 
 /*
-  Use bicubic interpolation for the affine transformation
+  Darken image pre-resize (1/gamma) and brighten post-resize (gamma).
+  Improves brightness of resized image in non-linear colour spaces.
 */
-Sharp.prototype.bicubicInterpolation = function() {
-  this.options.interpolator = 'bicubic';
+Sharp.prototype.gamma = function(gamma) {
+  if (typeof gamma === 'undefined') {
+    // Default gamma correction of 2.2 (sRGB)
+    this.options.gamma = 2.2;
+  } else if (!Number.isNaN(gamma) && gamma >= 1 && gamma <= 3) {
+    this.options.gamma = gamma;
+  } else {
+    throw new Error('Invalid gamma correction (1.0 to 3.0) ' + gamma);
+  }
   return this;
 };
 
 /*
-  Use Nohalo interpolation for the affine transformation
+  Convert to greyscale
 */
-Sharp.prototype.nohaloInterpolation = function() {
-  this.options.interpolator = 'nohalo';
+Sharp.prototype.greyscale = function(greyscale) {
+  this.options.greyscale = (typeof greyscale === 'boolean') ? greyscale : true;
   return this;
 };
+Sharp.prototype.grayscale = Sharp.prototype.greyscale;
 
 Sharp.prototype.progressive = function(progressive) {
   this.options.progressive = (typeof progressive === 'boolean') ? progressive : true;
@@ -131,14 +248,19 @@ Sharp.prototype.quality = function(quality) {
 };
 
 Sharp.prototype.compressionLevel = function(compressionLevel) {
-  if (!Number.isNaN(compressionLevel) && compressionLevel >= -1 && compressionLevel <= 9) {
+  if (!Number.isNaN(compressionLevel) && compressionLevel >= 0 && compressionLevel <= 9) {
     this.options.compressionLevel = compressionLevel;
   } else {
-    throw new Error('Invalid compressionLevel (-1 to 9) ' + compressionLevel);
+    throw new Error('Invalid compressionLevel (0 to 9) ' + compressionLevel);
   }
   return this;
 };
 
+Sharp.prototype.withMetadata = function(withMetadata) {
+  this.options.withMetadata = (typeof withMetadata === 'boolean') ? withMetadata : true;
+  return this;
+};
+
 Sharp.prototype.resize = function(width, height) {
   if (!width) {
     this.options.width = -1;
@@ -181,61 +303,184 @@ Sharp.prototype.toFile = function(output, callback) {
         return Promise.reject(errOutputIsInput);
       }
     } else {
-      return this._sharp(output, callback);
+      this.options.output = output;
+      return this._sharp(callback);
     }
   }
   return this;
 };
 
-// Deprecated to make way for future stream support - remove in v0.6.0
-Sharp.prototype.write = require('util').deprecate(
-  Sharp.prototype.toFile,
-  '.write() is deprecated and will be removed in v0.6.0. Use .toFile() instead.'
-);
-
 Sharp.prototype.toBuffer = function(callback) {
-  return this._sharp('__input', callback);
+  return this._sharp(callback);
 };
 
-Sharp.prototype.jpeg = function(callback) {
-  return this._sharp('__jpeg', callback);
+Sharp.prototype.jpeg = function() {
+  this.options.output = '__jpeg';
+  return this;
 };
 
-Sharp.prototype.png = function(callback) {
-  return this._sharp('__png', callback);
+Sharp.prototype.png = function() {
+  this.options.output = '__png';
+  return this;
 };
 
-Sharp.prototype.webp = function(callback) {
-  return this._sharp('__webp', callback);
+Sharp.prototype.webp = function() {
+  this.options.output = '__webp';
+  return this;
+};
+
+/*
+  Used by a Writable Stream to notify that it is ready for data
+*/
+Sharp.prototype._read = function() {
+  if (!this.options.streamOut) {
+    this.options.streamOut = true;
+    this._sharp();
+  }
 };
 
 /*
   Invoke the C++ image processing pipeline
-  Supports callback and promise variants
+  Supports callback, stream and promise variants
 */
-Sharp.prototype._sharp = function(output, callback) {
+Sharp.prototype._sharp = function(callback) {
+  var that = this;
   if (typeof callback === 'function') {
-    // I like callbacks
-    sharp.resize(this.options, output, callback);
+    // output=file/buffer
+    if (this.options.streamIn) {
+      // output=file/buffer, input=stream
+      this.on('finish', function() {
+        sharp.resize(that.options, callback);
+      });
+    } else {
+      // output=file/buffer, input=file/buffer
+      sharp.resize(this.options, callback);
+    }
+    return this;
+  } else if (this.options.streamOut) {
+    // output=stream
+    if (this.options.streamIn) {
+      // output=stream, input=stream
+      this.on('finish', function() {
+        sharp.resize(that.options, function(err, data) {
+          if (err) {
+            that.emit('error', new Error(err));
+          } else {
+            that.push(data);
+          }
+          that.push(null);
+        });
+      });
+    } else {
+      // output=stream, input=file/buffer
+      sharp.resize(this.options, function(err, data) {
+        if (err) {
+          that.emit('error', new Error(err));
+        } else {
+          that.push(data);
+        }
+        that.push(null);
+      });
+    }
     return this;
   } else {
-    // I like promises
-    var options = this.options;
-    return new Promise(function(resolve, reject) {
-      sharp.resize(options, output, function(err, data) {
-        if (err) {
-          reject(err);
-        } else {
-          resolve(data);
-        }
+    // output=promise
+    if (this.options.streamIn) {
+      // output=promise, input=stream
+      return new Promise(function(resolve, reject) {
+        that.on('finish', function() {
+          sharp.resize(that.options, function(err, data) {
+            if (err) {
+              reject(err);
+            } else {
+              resolve(data);
+            }
+          });
+        });
       });
-    });
+    } else {
+      // output=promise, input=file/buffer
+      return new Promise(function(resolve, reject) {
+        sharp.resize(that.options, function(err, data) {
+          if (err) {
+            reject(err);
+          } else {
+            resolve(data);
+          }
+        });
+      });
+    }
   }
 };
 
-module.exports.cache = function(limit) {
-  if (Number.isNaN(limit)) {
-    limit = null;
+/*
+  Reads the image header and returns metadata
+  Supports callback, stream and promise variants
+*/
+Sharp.prototype.metadata = function(callback) {
+  var that = this;
+  if (typeof callback === 'function') {
+    if (this.options.streamIn) {
+      this.on('finish', function() {
+        sharp.metadata(that.options, callback);
+      });
+    } else {
+      sharp.metadata(this.options, callback);
+    }
+    return this;
+  } else {
+    if (this.options.streamIn) {
+      return new Promise(function(resolve, reject) {
+        that.on('finish', function() {
+          sharp.metadata(that.options, function(err, data) {
+            if (err) {
+              reject(err);
+            } else {
+              resolve(data);
+            }
+          });
+        });
+      });
+    } else {
+      return new Promise(function(resolve, reject) {
+        sharp.metadata(that.options, function(err, data) {
+          if (err) {
+            reject(err);
+          } else {
+            resolve(data);
+          }
+        });
+      });
+    }
   }
-  return sharp.cache(limit);
+};
+
+/*
+  Get and set cache memory and item limits
+*/
+module.exports.cache = function(memory, items) {
+  if (Number.isNaN(memory)) {
+    memory = null;
+  }
+  if (Number.isNaN(items)) {
+    items = null;
+  }
+  return sharp.cache(memory, items);
+};
+
+/*
+  Get and set size of thread pool
+*/
+module.exports.concurrency = function(concurrency) {
+  if (Number.isNaN(concurrency)) {
+    concurrency = null;
+  }
+  return sharp.concurrency(concurrency);
+};
+
+/*
+  Get internal counters
+*/
+module.exports.counters = function() {
+  return sharp.counters();
 };

package.json

@@ -1,10 +1,16 @@
 {
   "name": "sharp",
-  "version": "0.5.1",
+  "version": "0.7.0",
   "author": "Lovell Fuller <npm@lovell.info>",
   "contributors": [
     "Pierre Inglebert <pierre.inglebert@gmail.com>",
-    "Jonathan Ong <jonathanrichardong@gmail.com>"
+    "Jonathan Ong <jonathanrichardong@gmail.com>",
+    "Chanon Sajjamanochai <chanon.s@gmail.com>",
+    "Juliano Julio <julianojulio@gmail.com>",
+    "Daniel Gasienica <daniel@gasienica.ch>",
+    "Julian Walker <julian@fiftythree.com>",
+    "Amit Pitaru <pitaru.amit@gmail.com>",
+    "Brandon Aaron <hello.brandon@aaron.sh>"
   ],
   "description": "High performance Node.js module to resize JPEG, PNG and WebP images using the libvips library",
   "scripts": {
@@ -25,19 +31,22 @@
     "thumbnail",
     "sharpen",
     "crop",
+    "extract",
     "embed",
     "libvips",
     "vips",
     "fast",
-    "buffer"
+    "buffer",
+    "stream"
   ],
   "dependencies": {
-    "nan": "^1.2.0",
-    "bluebird": "^2.1.2"
+    "bluebird": "^2.3.5",
+    "color": "^0.7.1",
+    "nan": "^1.3.0"
   },
   "devDependencies": {
     "imagemagick": "^0.1.3",
-    "imagemagick-native": "^1.1.1",
+    "imagemagick-native": "^1.4.0",
     "gm": "^1.16.0",
     "async": "^0.9.0",
     "benchmark": "^1.0.0"

tests/leak.sh

@@ -0,0 +1,7 @@
+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
+G_SLICE=always-malloc G_DEBUG=gc-friendly valgrind --suppressions=libvips.supp --suppressions=sharp.supp --leak-check=full --show-leak-kinds=definite,indirect,possible --num-callers=20 node unit.js

tests/parallel.js

@@ -1,32 +1,42 @@
-var sharp = require("../index");
-var fs = require("fs");
-var path = require("path");
-var assert = require("assert");
-var async = require("async");
-
-var inputJpg = path.join(__dirname, "fixtures/2569067123_aca715a2ee_o.jpg"); // http://www.flickr.com/photos/grizdave/2569067123/
-var width = 720;
-var height = 480;
-
-async.mapSeries([1, 1, 2, 4, 8, 16, 32, 64, 128], function(parallelism, next) {
-  var start = new Date().getTime();
-  async.times(parallelism,
-    function(id, callback) {
-      sharp(inputJpg).resize(width, height).toBuffer(function(err, buffer) {
-        buffer = null;
-        callback(err, new Date().getTime() - start);
-      });
-    },
-    function(err, ids) {
-      assert(!err);
-      assert(ids.length === parallelism);
-      var mean = ids.reduce(function(a, b) {
-        return a + b;
-      }) / ids.length;
-      console.log(parallelism + " parallel calls: fastest=" + ids[0] + "ms slowest=" + ids[ids.length - 1] + "ms mean=" + mean + "ms");
-      next();
-    }
-  );
-}, function() {
-  console.dir(sharp.cache());
-});
+/*jslint node: true */
+'use strict';
+
+var sharp = require('../index');
+var path = require('path');
+var assert = require('assert');
+var async = require('async');
+
+var inputJpg = path.join(__dirname, 'fixtures/2569067123_aca715a2ee_o.jpg'); // http://www.flickr.com/photos/grizdave/2569067123/
+var width = 720;
+var height = 480;
+
+sharp.concurrency(1);
+
+var timer = setInterval(function() {
+  console.dir(sharp.counters());
+}, 100);
+
+async.mapSeries([1, 1, 2, 4, 8, 16, 32, 64, 128], function(parallelism, next) {
+  var start = new Date().getTime();
+  async.times(parallelism,
+    function(id, callback) {
+      /*jslint unused: false */
+      sharp(inputJpg).resize(width, height).toBuffer(function(err, buffer) {
+        buffer = null;
+        callback(err, new Date().getTime() - start);
+      });
+    },
+    function(err, ids) {
+      assert(!err);
+      assert(ids.length === parallelism);
+      var mean = ids.reduce(function(a, b) {
+        return a + b;
+      }) / ids.length;
+      console.log(parallelism + ' parallel calls: fastest=' + ids[0] + 'ms slowest=' + ids[ids.length - 1] + 'ms mean=' + mean + 'ms');
+      next();
+    }
+  );
+}, function() {
+  clearInterval(timer);
+  console.dir(sharp.counters());
+});

tests/random.js

@@ -1,68 +1,69 @@
-var sharp = require("../index");
-var fs = require("fs");
-var path = require("path");
-var imagemagick = require("imagemagick");
-var gm = require("gm");
-var async = require("async");
-var assert = require("assert");
-var Benchmark = require("benchmark");
-
-var fixturesPath = path.join(__dirname, "fixtures");
-var inputJpg = path.join(fixturesPath, "2569067123_aca715a2ee_o.jpg"); // http://www.flickr.com/photos/grizdave/2569067123/
-var outputJpg = path.join(fixturesPath, "output.jpg");
-
-var min = 320;
-var max = 960;
-
-var randomDimension = function() {
-  return Math.random() * (max - min) + min;
-};
-
-new Benchmark.Suite("random").add("imagemagick", {
-	defer: true,
-	fn: function(deferred) {
-		imagemagick.resize({
-			srcPath: inputJpg,
-			dstPath: outputJpg,
-			quality: 0.8,
-			width: randomDimension(),
-			height: randomDimension()
-		}, function(err) {
-			if (err) {
-				throw err;
-			} else {
-				deferred.resolve();
-			}
-		});
-	}
-}).add("gm", {
-	defer: true,
-	fn: function(deferred) {
-		gm(inputJpg).resize(randomDimension(), randomDimension()).quality(80).toBuffer(function (err, buffer) {
-			if (err) {
-				throw err;
-			} else {
-				assert.notStrictEqual(null, buffer);
-				deferred.resolve();
-			}
-		});
-	}
-}).add("sharp", {
-	defer: true,
-	fn: function(deferred) {
-		sharp(inputJpg).resize(randomDimension(), randomDimension()).toBuffer(function(err, buffer) {
-			if (err) {
-				throw err;
-			} else {
-				assert.notStrictEqual(null, buffer);
-				deferred.resolve();
-			}
-		});
-	}
-}).on("cycle", function(event) {
-  console.log(String(event.target));
-}).on("complete", function() {
-  var winner = this.filter("fastest").pluck("name");
-  assert.strictEqual("sharp", String(winner), "sharp was slower than " + winner);
-	console.dir(sharp.cache());
-}).run();
+/*jslint node: true */
+'use strict';
+
+var sharp = require('../index');
+var path = require('path');
+var imagemagick = require('imagemagick');
+var gm = require('gm');
+var assert = require('assert');
+var Benchmark = require('benchmark');
+
+var fixturesPath = path.join(__dirname, 'fixtures');
+var inputJpg = path.join(fixturesPath, '2569067123_aca715a2ee_o.jpg'); // http://www.flickr.com/photos/grizdave/2569067123/
+var outputJpg = path.join(fixturesPath, 'output.jpg');
+
+var min = 320;
+var max = 960;
+
+var randomDimension = function() {
+  return Math.random() * (max - min) + min;
+};
+
+new Benchmark.Suite('random').add('imagemagick', {
+	defer: true,
+	fn: function(deferred) {
+		imagemagick.resize({
+			srcPath: inputJpg,
+			dstPath: outputJpg,
+			quality: 0.8,
+			width: randomDimension(),
+			height: randomDimension()
+		}, function(err) {
+			if (err) {
+				throw err;
+			} else {
+				deferred.resolve();
+			}
+		});
+	}
+}).add('gm', {
+	defer: true,
+	fn: function(deferred) {
+		gm(inputJpg).resize(randomDimension(), randomDimension()).quality(80).toBuffer(function (err, buffer) {
+			if (err) {
+				throw err;
+			} else {
+				assert.notStrictEqual(null, buffer);
+				deferred.resolve();
+			}
+		});
+	}
+}).add('sharp', {
+	defer: true,
+	fn: function(deferred) {
+		sharp(inputJpg).resize(randomDimension(), randomDimension()).toBuffer(function(err, buffer) {
+			if (err) {
+				throw err;
+			} else {
+				assert.notStrictEqual(null, buffer);
+				deferred.resolve();
+			}
+		});
+	}
+}).on('cycle', function(event) {
+  console.log(String(event.target));
+}).on('complete', function() {
+  var winner = this.filter('fastest').pluck('name');
+  assert.strictEqual('sharp', String(winner), 'sharp was slower than ' + winner);
+	console.dir(sharp.cache());
+}).run();

tests/sharp.supp

@@ -0,0 +1,111 @@
+# libjpeg warnings
+{
+  cond_jpeg_read_scanlines
+  Memcheck:Cond
+  ...
+  fun:jpeg_read_scanlines
+}
+{
+  value_jpeg_read_scanlines
+  Memcheck:Value8
+  ...
+  fun:jpeg_read_scanlines
+}
+{
+  cond_jpeg_write_scanlines
+  Memcheck:Cond
+  ...
+  fun:jpeg_write_scanlines
+}
+{
+  cond_jpeg_finish_compress
+  Memcheck:Cond
+  ...
+  fun:jpeg_finish_compress
+}
+{
+  value_jpeg_finish_compress
+  Memcheck:Value8
+  ...
+  fun:jpeg_finish_compress
+}
+
+# libvips interpolator warnings
+{
+  cond_libvips_interpolate_lbb
+  Memcheck:Cond
+  ...
+  fun:_ZL32vips_interpolate_lbb_interpolateP16_VipsInterpolatePvP11_VipsRegiondd
+  fun:vips_affine_gen
+}
+
+# libuv warnings
+{
+  free_libuv
+  Memcheck:Free
+  ...
+  fun:uv__work_done
+}
+
+# nodejs warnings
+{
+  param_nodejs_write_buffer
+  Memcheck:Param
+  write(buf)
+  ...
+  obj:/usr/bin/nodejs
+}
+{
+  leak_nodejs_ImmutableAsciiSource_CreateFromLiteral
+  Memcheck:Leak
+  match-leak-kinds: definite
+  ...
+  fun:_ZN4node20ImmutableAsciiSource17CreateFromLiteralEPKcm
+}
+{
+  leak_nodejs_Buffer_New
+  Memcheck:Leak
+  match-leak-kinds: definite
+  ...
+  fun:_ZN4node6Buffer3NewERKN2v89ArgumentsE
+}
+{
+  leak_nodejs_Buffer_Replace
+   Memcheck:Leak
+   match-leak-kinds: indirect,possible
+   ...
+   fun:_ZN4node6Buffer7ReplaceEPcmPFvS1_PvES2_
+}
+{
+  leak_nodejs_SignalWrap_New
+  Memcheck:Leak
+  match-leak-kinds: possible
+  ...
+  fun:_ZN4node10SignalWrap3NewERKN2v89ArgumentsE
+}
+{
+  leak_nodejs_TTYWrap_New
+  Memcheck:Leak
+  match-leak-kinds: possible
+  ...
+  fun:_ZN4node7TTYWrap3NewERKN2v89ArgumentsE
+}
+{
+  leak_nodejs_ares_init_options
+  Memcheck:Leak
+  match-leak-kinds: reachable
+  fun:malloc
+  fun:strdup
+  ...
+  fun:ares_init_options
+}
+
+# vips__init warnings
+{
+  leak_libvips_init
+  Memcheck:Leak
+  match-leak-kinds: reachable
+  fun:malloc
+  ...
+  fun:vips__init
+}