Small doc improvements ahead of v0.6.0

Pass additional info (width, height) to output callback

README.md

@@ -9,15 +9,17 @@
 
 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
 
@@ -34,6 +36,10 @@ _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
@@ -89,29 +95,74 @@ 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)
+  .sharpen()
+  .quality(90)
+  .webp()
+  .toBuffer()
+  .then(function(outputBuffer) {
+    // outputBuffer contains 300px wide, upside down, sharpened,
+    // 90% quality WebP image data
+  });
 ```
 
 ```javascript
-sharp('input.gif').resize(200, 300).embedBlack().webp(function(err, outputBuffer) {
+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, 300)
+  .interpolateWith(sharp.interpolator.nohalo)
+  .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 inputBuffer
+  });
+```
+
+```javascript
+sharp('input.gif').resize(200, 300).embedBlack().webp().toBuffer(function(err, outputBuffer) {
   if (err) {
     throw err;
   }
@@ -121,7 +172,7 @@ sharp('input.gif').resize(200, 300).embedBlack().webp(function(err, outputBuffer
 ```
 
 ```javascript
-sharp(inputBuffer).resize(200, 200).max().jpeg().then(function(outputBuffer) {
+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
 });
@@ -129,14 +180,43 @@ sharp(inputBuffer).resize(200, 200).max().jpeg().then(function(outputBuffer) {
 
 ## 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
+* `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.
 
@@ -144,25 +224,29 @@ 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()
+#### 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`.
+
+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()
+#### embedWhite()
 
 Embed the resized image on a white background of the exact size specified.
 
-### embedBlack()
+#### embedBlack()
 
 Embed the resized image on a black background of the exact size specified.
 
-### rotate([angle])
+#### rotate([angle])
 
 Rotate the output image by either an explicit angle or auto-orient based on the EXIF `Orientation` tag.
 
@@ -170,100 +254,109 @@ Rotate the output image by either an explicit angle or auto-orient based on the
 
 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%.
 
-### 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%.
+* `bilinear`: Use [bilinear interpolation](http://en.wikipedia.org/wiki/Bilinear_interpolation), the default (and fastest) 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" when enlarging 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()
+### Output options
 
-Use [Nohalo interpolation](http://eprints.soton.ac.uk/268086/) for image resizing. This typically reduces performance by a factor of 2.
-
-### progressive()
+#### 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.
 
-### quality(quality)
+#### 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)
+#### 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.
 
-### sequentialRead()
+#### jpeg()
 
-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.
+Use JPEG format for the output image.
 
-### toFile(filename, [callback])
+#### png()
+
+Use PNG format for the output image.
+
+#### webp()
+
+Use WebP format for the output image.
+
+### 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 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 final resized image dimensions in its `width` and `height` properties
 
 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 resultant image data
+* `info` contains the final resized image dimensions in its `width` and `height` properties
 
 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.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 stats = sharp.cache(); // { current: 98, high: 115, limit: 100, queue: 0 }
-sharp.cache(200); // { current: 98, high: 115, limit: 200, queue: 0 }
-sharp.cache(50); // { current: 49, high: 115, limit: 50, queue: 0 }
+var counters = sharp.counters(); // { queue: 2, process: 4 }
 ```
 
 ## Testing
@@ -320,7 +413,7 @@ You can expect much greater performance with caching enabled (default) and using
 
 ## Licence
 
-Copyright 2013, 2014 Lovell Fuller and Pierre Inglebert
+Copyright 2013, 2014 Lovell Fuller, Pierre Inglebert, Jonathan Ong and Chanon Sajjamanochai
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.

binding.gyp

@@ -13,9 +13,9 @@
       '<!(node -e "require(\'nan\')")'
     ],
     'cflags': ['-fexceptions', '-Wall', '-O3'],
-    'cflags_cc': ['-fexceptions', '-Wall', '-O3'],
+    'cflags_cc': ['-std=c++0x', '-fexceptions', '-Wall', '-O3'],
     'xcode_settings': {
-      'OTHER_CFLAGS': ['-fexceptions', '-Wall', '-O3']
+      'OTHER_CFLAGS': ['-std=c++11', '-fexceptions', '-Wall', '-O3']
     }
   }]
 }

index.js

@@ -1,6 +1,8 @@
 /*jslint node: true */
 'use strict';
 
+var util = require('util');
+var stream = require('stream');
 var Promise = require('bluebird');
 var sharp = require('./build/Release/sharp');
 
@@ -8,10 +10,12 @@ var Sharp = function(input) {
   if (!(this instanceof Sharp)) {
     return new Sharp(input);
   }
+  stream.Duplex.call(this);
   this.options = {
     width: -1,
     height: -1,
     canvas: 'c',
+    gravity: 0,
     angle: 0,
     withoutEnlargement: false,
     sharpen: false,
@@ -20,25 +24,68 @@ var Sharp = function(input) {
     sequentialRead: false,
     quality: 80,
     compressionLevel: 6,
-    output: '__jpeg'
+    streamIn: false,
+    streamOut: false,
+    output: '__input'
   };
   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) {
+  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;
 };
 
@@ -88,28 +135,32 @@ 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 = {
+  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
+  Deprecated interpolation methods, to be removed in v0.7.0
 */
-Sharp.prototype.bicubicInterpolation = function() {
-  this.options.interpolator = 'bicubic';
-  return this;
-};
-
-/*
-  Use Nohalo interpolation for the affine transformation
-*/
-Sharp.prototype.nohaloInterpolation = function() {
-  this.options.interpolator = 'nohalo';
-  return this;
-};
+Sharp.prototype.bilinearInterpolation = util.deprecate(function() {
+  return this.interpolateWith(module.exports.interpolator.bilinear);
+}, 'bilinearInterpolation() is deprecated, use interpolateWith(sharp.interpolator.bilinear) instead');
+Sharp.prototype.bicubicInterpolation = util.deprecate(function() {
+  return this.interpolateWith(module.exports.interpolator.bicubic);
+}, 'bicubicInterpolation() is deprecated, use interpolateWith(sharp.interpolator.bicubic) instead');
+Sharp.prototype.nohaloInterpolation = util.deprecate(function() {
+  return this.interpolateWith(module.exports.interpolator.nohalo);
+}, 'nohaloInterpolation() is deprecated, use interpolateWith(sharp.interpolator.nohalo) instead');
 
 Sharp.prototype.progressive = function(progressive) {
   this.options.progressive = (typeof progressive === 'boolean') ? progressive : true;
@@ -181,61 +232,183 @@ 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';
+  if (arguments.length > 0) {
+    console.error('Use of the jpeg() method with a callback is deprecated in 0.6.x and will be removed in 0.7.x');
+    console.error('Please add toFile(), toBuffer() or Stream methods e.g. pipe() for JPEG output');
+    this._sharp(arguments);
+  }
+  return this;
 };
 
-Sharp.prototype.png = function(callback) {
-  return this._sharp('__png', callback);
+Sharp.prototype.png = function() {
+  this.options.output = '__png';
+  if (arguments.length > 0) {
+    console.error('Use of the png() method with a callback is deprecated in 0.6.x and will be removed in 0.7.x');
+    console.error('Please add toFile(), toBuffer() or Stream methods e.g. pipe() for PNG output');
+    this._sharp(arguments);
+  }
+  return this;
 };
 
-Sharp.prototype.webp = function(callback) {
-  return this._sharp('__webp', callback);
+Sharp.prototype.webp = function() {
+  this.options.output = '__webp';
+  if (arguments.length > 0) {
+    console.error('Use of the webp() method with a callback is deprecated in 0.6.x and will be removed in 0.7.x');
+    console.error('Please add toFile(), toBuffer() or Stream methods e.g. pipe() for WebP output');
+    this._sharp(arguments);
+  }
+  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) throw err;
+          that.push(data);
+          that.push(null);
+        });
+      });
+    } else {
+      // output=stream, input=file/buffer
+      sharp.resize(this.options, function(err, data) {
+        if (err) throw err;
+        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 internal counters
+*/
+module.exports.counters = function() {
+  return sharp.counters();
 };

package.json

@@ -1,10 +1,11 @@
 {
   "name": "sharp",
-  "version": "0.5.2",
+  "version": "0.6.0",
   "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>"
   ],
   "description": "High performance Node.js module to resize JPEG, PNG and WebP images using the libvips library",
   "scripts": {
@@ -29,11 +30,12 @@
     "libvips",
     "vips",
     "fast",
-    "buffer"
+    "buffer",
+    "stream"
   ],
   "dependencies": {
-    "nan": "^1.2.0",
-    "bluebird": "^2.2.1"
+    "nan": "^1.3.0",
+    "bluebird": "^2.3.0"
   },
   "devDependencies": {
     "imagemagick": "^0.1.3",

src/sharp.cc

@@ -3,6 +3,7 @@
 #include <math.h>
 #include <string>
 #include <string.h>
+#include <tuple>
 #include <vips/vips.h>
 
 #include "nan.h"
@@ -14,12 +15,13 @@ struct resize_baton {
   std::string file_in;
   void* buffer_in;
   size_t buffer_in_len;
-  std::string file_out;
+  std::string output;
   void* buffer_out;
   size_t buffer_out_len;
   int width;
   int height;
   bool crop;
+  int gravity;
   bool max;
   VipsExtend extend;
   bool sharpen;
@@ -36,6 +38,7 @@ struct resize_baton {
     buffer_in_len(0),
     buffer_out_len(0),
     crop(false),
+    gravity(0),
     max(false),
     sharpen(false),
     progressive(false),
@@ -43,6 +46,7 @@ struct resize_baton {
 };
 
 typedef enum {
+  UNKNOWN,
   JPEG,
   PNG,
   WEBP,
@@ -55,7 +59,9 @@ unsigned char const MARKER_PNG[] = {0x89, 0x50};
 unsigned char const MARKER_WEBP[] = {0x52, 0x49};
 
 // How many tasks are in the queue?
-volatile int queue_length = 0;
+volatile int counter_queue = 0;
+// How many tasks are being processed?
+volatile int counter_process = 0;
 
 static bool ends_with(std::string const &str, std::string const &end) {
   return str.length() >= end.length() && 0 == str.compare(str.length() - end.length(), end.length(), end);
@@ -92,7 +98,8 @@ static void resize_error(resize_baton *baton, VipsImage *unref) {
    2. Use input image EXIF Orientation header (does not support mirroring)
    3. Otherwise default to zero, i.e. no rotation
 */
-static VipsAngle calc_rotation(int const angle, VipsImage const *input) {
+static VipsAngle
+sharp_calc_rotation(int const angle, VipsImage const *input) {
   VipsAngle rotate = VIPS_ANGLE_0;
   if (angle == -1) {
     const char *exif;
@@ -117,64 +124,253 @@ static VipsAngle calc_rotation(int const angle, VipsImage const *input) {
   return rotate;
 }
 
-class ResizeWorker : public NanAsyncWorker {
- public:
-  ResizeWorker(NanCallback *callback, resize_baton *baton)
-    : NanAsyncWorker(callback), baton(baton) {}
-  ~ResizeWorker() {}
+/*
+  Calculate the (left, top) coordinates of the output image
+  within the input image, applying the given gravity.
+*/
+static std::tuple<int, int>
+sharp_calc_crop(int const inWidth, int const inHeight, int const outWidth, int const outHeight, int const gravity) {
+  int left = 0;
+  int top = 0;
+  switch (gravity) {
+    case 1: // North
+      left = (inWidth - outWidth + 1) / 2;
+      break;
+    case 2: // East
+      left = inWidth - outWidth;
+      top = (inHeight - outHeight + 1) / 2;
+      break;
+    case 3: // South
+      left = (inWidth - outWidth + 1) / 2;
+      top = inHeight - outHeight;
+      break;
+    case 4: // West
+      top = (inHeight - outHeight + 1) / 2;
+      break;
+    default: // Centre
+      left = (inWidth - outWidth + 1) / 2;
+      top = (inHeight - outHeight + 1) / 2;
+  }
+  return std::make_tuple(left, top);
+}
 
-  void Execute () {
-    // Input
-    ImageType inputImageType = JPEG;
-    VipsImage *in = vips_image_new();
+/*
+  Initialise a VipsImage from a buffer. Supports JPEG, PNG and WebP.
+  Returns the ImageType detected, if any.
+*/
+static ImageType
+sharp_init_image_from_buffer(VipsImage **image, void *buffer, size_t const length, VipsAccess const access) {
+  ImageType imageType = UNKNOWN;
+  if (memcmp(MARKER_JPEG, buffer, 2) == 0) {
+    if (!vips_jpegload_buffer(buffer, length, image, "access", access, NULL)) {
+      imageType = JPEG;
+    }
+  } else if(memcmp(MARKER_PNG, buffer, 2) == 0) {
+    if (!vips_pngload_buffer(buffer, length, image, "access", access, NULL)) {
+      imageType = PNG;
+    }
+  } else if(memcmp(MARKER_WEBP, buffer, 2) == 0) {
+    if (!vips_webpload_buffer(buffer, length, image, "access", access, NULL)) {
+      imageType = WEBP;
+    }
+  }
+  return imageType;
+}
+
+/*
+  Initialise a VipsImage from a file.
+  Returns the ImageType detected, if any.
+*/
+static ImageType
+sharp_init_image_from_file(VipsImage **image, char const *file, VipsAccess const access) {
+  ImageType imageType = UNKNOWN;
+  if (vips_foreign_is_a("jpegload", file)) {
+    if (!vips_jpegload(file, image, "access", access, NULL)) {
+      imageType = JPEG;
+    }
+  } else if (vips_foreign_is_a("pngload", file)) {
+    if (!vips_pngload(file, image, "access", access, NULL)) {
+      imageType = PNG;
+    }
+  } else if (vips_foreign_is_a("webpload", file)) {
+    if (!vips_webpload(file, image, "access", access, NULL)) {
+      imageType = WEBP;
+    }
+  } else if (vips_foreign_is_a("tiffload", file)) {
+    if (!vips_tiffload(file, image, "access", access, NULL)) {
+      imageType = TIFF;
+    }
+  } else if(vips_foreign_is_a("magickload", file)) {
+    if (!vips_magickload(file, image, "access", access, NULL)) {
+      imageType = MAGICK;
+    }
+  }
+  return imageType;
+}
+
+// Metadata
+
+struct metadata_baton {
+  // Input
+  std::string file_in;
+  void* buffer_in;
+  size_t buffer_in_len;
+  // Output
+  std::string format;
+  int width;
+  int height;
+  std::string space;
+  int channels;
+  int orientation;
+  std::string err;
+
+  metadata_baton():
+    buffer_in_len(0),
+    orientation(0) {}
+};
+
+class MetadataWorker : public NanAsyncWorker {
+
+  public:
+    MetadataWorker(NanCallback *callback, metadata_baton *baton) : NanAsyncWorker(callback), baton(baton) {}
+    ~MetadataWorker() {}
+
+  void Execute() {
+    // Decrement queued task counter
+    g_atomic_int_dec_and_test(&counter_queue);
+
+    ImageType imageType = UNKNOWN;
+    VipsImage *image = vips_image_new();
     if (baton->buffer_in_len > 1) {
-      if (memcmp(MARKER_JPEG, baton->buffer_in, 2) == 0) {
-        if (vips_jpegload_buffer(baton->buffer_in, baton->buffer_in_len, &in, "access", baton->access_method, NULL)) {
-          return resize_error(baton, in);
-        }
-      } else if(memcmp(MARKER_PNG, baton->buffer_in, 2) == 0) {
-        inputImageType = PNG;
-        if (vips_pngload_buffer(baton->buffer_in, baton->buffer_in_len, &in, "access", baton->access_method, NULL)) {
-          return resize_error(baton, in);
-        }
-      } else if(memcmp(MARKER_WEBP, baton->buffer_in, 2) == 0) {
-        inputImageType = WEBP;
-        if (vips_webpload_buffer(baton->buffer_in, baton->buffer_in_len, &in, "access", baton->access_method, NULL)) {
-          return resize_error(baton, in);
-        }
-      } else {
-        resize_error(baton, in);
-        (baton->err).append("Unsupported input buffer");
-        return;
-      }
-    } else if (vips_foreign_is_a("jpegload", baton->file_in.c_str())) {
-      if (vips_jpegload((baton->file_in).c_str(), &in, "access", baton->access_method, NULL)) {
-        return resize_error(baton, in);
-      }
-    } else if (vips_foreign_is_a("pngload", baton->file_in.c_str())) {
-      inputImageType = PNG;
-      if (vips_pngload((baton->file_in).c_str(), &in, "access", baton->access_method, NULL)) {
-        return resize_error(baton, in);
-      }
-    } else if (vips_foreign_is_a("webpload", baton->file_in.c_str())) {
-      inputImageType = WEBP;
-      if (vips_webpload((baton->file_in).c_str(), &in, "access", baton->access_method, NULL)) {
-        return resize_error(baton, in);
-      }
-    } else if (vips_foreign_is_a("tiffload", baton->file_in.c_str())) {
-      inputImageType = TIFF;
-      if (vips_tiffload((baton->file_in).c_str(), &in, "access", baton->access_method, NULL)) {
-        return resize_error(baton, in);
-      }
-    } else if(vips_foreign_is_a("magickload", (baton->file_in).c_str())) {
-      inputImageType = MAGICK;
-      if (vips_magickload((baton->file_in).c_str(), &in, "access", baton->access_method, NULL)) {
-        return resize_error(baton, in);
+      // From buffer
+      imageType = sharp_init_image_from_buffer(&image, baton->buffer_in, baton->buffer_in_len, VIPS_ACCESS_RANDOM);
+      if (imageType == UNKNOWN) {
+        (baton->err).append("Input buffer contains unsupported image format");
       }
     } else {
-      resize_error(baton, in);
-      (baton->err).append("Unsupported input file " + baton->file_in);
-      return;
+      // From file
+      imageType = sharp_init_image_from_file(&image, baton->file_in.c_str(), VIPS_ACCESS_RANDOM);
+      if (imageType == UNKNOWN) {
+        (baton->err).append("File is of an unsupported image format");
+      }
+    }
+    if (imageType != UNKNOWN) {
+      // Image type
+      switch (imageType) {
+        case JPEG: baton->format = "jpeg"; break;
+        case PNG: baton->format = "png"; break;
+        case WEBP: baton->format = "webp"; break;
+        case TIFF: baton->format = "tiff"; break;
+        case MAGICK: baton->format = "magick"; break;
+        case UNKNOWN: default: baton->format = "";
+      }
+      // VipsImage attributes
+      baton->width = image->Xsize;
+      baton->height = image->Ysize;
+      baton->space = vips_enum_nick(VIPS_TYPE_INTERPRETATION, image->Type);
+      baton->channels = image->Bands;
+      // EXIF Orientation
+      const char *exif;
+      if (!vips_image_get_string(image, "exif-ifd0-Orientation", &exif)) {
+        baton->orientation = atoi(&exif[0]);
+      }
+    }
+    // Clean up
+    g_object_unref(image);
+    vips_error_clear();
+    vips_thread_shutdown();
+  }
+
+  void HandleOKCallback () {
+    NanScope();
+
+    Handle<Value> argv[2] = { NanNull(), NanNull() };
+    if (!baton->err.empty()) {
+      // Error
+      argv[0] = NanNew<String>(baton->err.data(), baton->err.size());
+    } 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));
+      if (baton->orientation > 0) {
+        info->Set(NanNew<String>("orientation"), NanNew<Number>(baton->orientation));
+      }
+      argv[1] = info;
+    }
+    delete baton;
+
+    // Return to JavaScript
+    callback->Call(2, argv);
+  }
+
+  private:
+    metadata_baton* baton;
+};
+
+/*
+  metadata(options, callback)
+*/
+NAN_METHOD(metadata) {
+  NanScope();
+
+  // V8 objects are converted to non-V8 types held in the baton struct
+  metadata_baton *baton = new metadata_baton;
+  Local<Object> options = args[0]->ToObject();
+
+  // Input filename
+  baton->file_in = *String::Utf8Value(options->Get(NanNew<String>("fileIn"))->ToString());
+  // Input Buffer object
+  if (options->Get(NanNew<String>("bufferIn"))->IsObject()) {
+    Local<Object> buffer = options->Get(NanNew<String>("bufferIn"))->ToObject();
+    baton->buffer_in_len = Buffer::Length(buffer);
+    baton->buffer_in = Buffer::Data(buffer);
+  }
+
+  // Join queue for worker thread
+  NanCallback *callback = new NanCallback(args[1].As<v8::Function>());
+  NanAsyncQueueWorker(new MetadataWorker(callback, baton));
+
+  // Increment queued task counter
+  g_atomic_int_inc(&counter_queue);
+
+  NanReturnUndefined();
+}
+
+// Resize
+
+class ResizeWorker : public NanAsyncWorker {
+  public:
+    ResizeWorker(NanCallback *callback, resize_baton *baton) : NanAsyncWorker(callback), baton(baton) {}
+    ~ResizeWorker() {}
+
+  void Execute() {
+    // Decrement queued task counter
+    g_atomic_int_dec_and_test(&counter_queue);
+    // Increment processing task counter
+    g_atomic_int_inc(&counter_process);
+
+    // Input
+    ImageType inputImageType = UNKNOWN;
+    VipsImage *in = vips_image_new();
+    if (baton->buffer_in_len > 1) {
+      // From buffer
+      inputImageType = sharp_init_image_from_buffer(&in, baton->buffer_in, baton->buffer_in_len, baton->access_method);
+      if (inputImageType == UNKNOWN) {
+        (baton->err).append("Input buffer contains unsupported image format");
+      }
+    } else {
+      // From file
+      inputImageType = sharp_init_image_from_file(&in, baton->file_in.c_str(), baton->access_method);
+      if (inputImageType == UNKNOWN) {
+        (baton->err).append("File is of an unsupported image format");
+      }
+    }
+    if (inputImageType == UNKNOWN) {
+      return resize_error(baton, in);
     }
 
     // Get input image width and height
@@ -182,7 +378,7 @@ class ResizeWorker : public NanAsyncWorker {
     int inputHeight = in->Ysize;
 
     // Calculate angle of rotation, to be carried out later
-    VipsAngle rotation = calc_rotation(baton->angle, in);
+    VipsAngle rotation = sharp_calc_rotation(baton->angle, in);
     if (rotation == VIPS_ANGLE_90 || rotation == VIPS_ANGLE_270) {
       // Swap input output width and height when rotating by 90 or 270 degrees
       int swap = inputWidth;
@@ -330,10 +526,11 @@ class ResizeWorker : public NanAsyncWorker {
     if (rotated->Xsize != baton->width || rotated->Ysize != baton->height) {
       if (baton->crop || baton->max) {
         // Crop/max
+        int left;
+        int top;
+        std::tie(left, top) = sharp_calc_crop(rotated->Xsize, rotated->Ysize, baton->width, baton->height, baton->gravity);
         int width = std::min(rotated->Xsize, baton->width);
         int height = std::min(rotated->Ysize, baton->height);
-        int left = (rotated->Xsize - width + 1) / 2;
-        int top = (rotated->Ysize - height + 1) / 2;
         if (vips_extract_area(rotated, &canvased, left, top, width, height, NULL)) {
           return resize_error(baton, rotated);
         }
@@ -386,64 +583,81 @@ class ResizeWorker : public NanAsyncWorker {
 
     // Output
     VipsImage *output = cached;
-    if (baton->file_out == "__jpeg" || (baton->file_out == "__input" && inputImageType == JPEG)) {
+    if (baton->output == "__jpeg" || (baton->output == "__input" && inputImageType == JPEG)) {
       // Write JPEG to buffer
       if (vips_jpegsave_buffer(output, &baton->buffer_out, &baton->buffer_out_len, "strip", TRUE, "Q", baton->quality, "optimize_coding", TRUE, "interlace", baton->progressive, NULL)) {
         return resize_error(baton, output);
       }
-    } else if (baton->file_out == "__png" || (baton->file_out == "__input" && inputImageType == PNG)) {
+    } else if (baton->output == "__png" || (baton->output == "__input" && inputImageType == PNG)) {
       // Write PNG to buffer
       if (vips_pngsave_buffer(output, &baton->buffer_out, &baton->buffer_out_len, "strip", TRUE, "compression", baton->compressionLevel, "interlace", baton->progressive, NULL)) {
         return resize_error(baton, output);
       }
-    } else if (baton->file_out == "__webp" || (baton->file_out == "__input" && inputImageType == WEBP)) {
+    } else if (baton->output == "__webp" || (baton->output == "__input" && inputImageType == WEBP)) {
       // Write WEBP to buffer
       if (vips_webpsave_buffer(output, &baton->buffer_out, &baton->buffer_out_len, "strip", TRUE, "Q", baton->quality, NULL)) {
         return resize_error(baton, output);
       }
-    } else if (is_jpeg(baton->file_out))  {
+    } else if (is_jpeg(baton->output))  {
       // Write JPEG to file
-      if (vips_jpegsave(output, baton->file_out.c_str(), "strip", TRUE, "Q", baton->quality, "optimize_coding", TRUE, "interlace", baton->progressive, NULL)) {
+      if (vips_jpegsave(output, baton->output.c_str(), "strip", TRUE, "Q", baton->quality, "optimize_coding", TRUE, "interlace", baton->progressive, NULL)) {
         return resize_error(baton, output);
       }
-    } else if (is_png(baton->file_out)) {
+    } else if (is_png(baton->output)) {
       // Write PNG to file
-      if (vips_pngsave(output, baton->file_out.c_str(), "strip", TRUE, "compression", baton->compressionLevel, "interlace", baton->progressive, NULL)) {
+      if (vips_pngsave(output, baton->output.c_str(), "strip", TRUE, "compression", baton->compressionLevel, "interlace", baton->progressive, NULL)) {
         return resize_error(baton, output);
       }
-    } else if (is_webp(baton->file_out)) {
+    } else if (is_webp(baton->output)) {
       // Write WEBP to file
-      if (vips_webpsave(output, baton->file_out.c_str(), "strip", TRUE, "Q", baton->quality, NULL)) {
+      if (vips_webpsave(output, baton->output.c_str(), "strip", TRUE, "Q", baton->quality, NULL)) {
         return resize_error(baton, output);
       }
-    } else if (is_tiff(baton->file_out)) {
+    } else if (is_tiff(baton->output)) {
       // Write TIFF to file
-      if (vips_tiffsave(output, baton->file_out.c_str(), "strip", TRUE, "compression", VIPS_FOREIGN_TIFF_COMPRESSION_JPEG, "Q", baton->quality, NULL)) {
+      if (vips_tiffsave(output, baton->output.c_str(), "strip", TRUE, "compression", VIPS_FOREIGN_TIFF_COMPRESSION_JPEG, "Q", baton->quality, NULL)) {
         return resize_error(baton, output);
       }
     } else {
-      (baton->err).append("Unsupported output " + baton->file_out);
+      (baton->err).append("Unsupported output " + baton->output);
     }
     g_object_unref(output);
+
+    // Clean up libvips' per-request data and threads
+    vips_error_clear();
     vips_thread_shutdown();
   }
 
   void HandleOKCallback () {
     NanScope();
 
-    Handle<Value> argv[2] = { NanNull(), NanNull() };
+    Handle<Value> argv[3] = { NanNull(), NanNull(),  NanNull() };
     if (!baton->err.empty()) {
       // Error
       argv[0] = NanNew<String>(baton->err.data(), baton->err.size());
-    } else if (baton->buffer_out_len > 0) {
-      // Buffer
-      argv[1] = NanNewBufferHandle((char *)baton->buffer_out, baton->buffer_out_len);
-      g_free(baton->buffer_out);
+    } else {
+      // Info Object
+      Local<Object> info = NanNew<Object>();
+      info->Set(NanNew<String>("width"), NanNew<Number>(baton->width));
+      info->Set(NanNew<String>("height"), NanNew<Number>(baton->height));
+
+      if (baton->buffer_out_len > 0) {
+        // Buffer
+        argv[1] = NanNewBufferHandle((char *)baton->buffer_out, baton->buffer_out_len);
+        g_free(baton->buffer_out);
+        argv[2] = info;
+      } else {
+        // File
+        argv[1] = info;
+      }
     }
     delete baton;
-    callback->Call(2, argv);
-    // Decrement queue length
-    g_atomic_int_dec_and_test(&queue_length);
+
+    // Decrement processing task counter
+    g_atomic_int_dec_and_test(&counter_process);
+
+    // Return to JavaScript
+    callback->Call(3, argv);
   }
 
  private:
@@ -483,6 +697,7 @@ NAN_METHOD(resize) {
     baton->max = true;
   }
   // Other options
+  baton->gravity = options->Get(NanNew<String>("gravity"))->Int32Value();
   baton->sharpen = options->Get(NanNew<String>("sharpen"))->BooleanValue();
   baton->interpolator = *String::Utf8Value(options->Get(NanNew<String>("interpolator"))->ToString());
   baton->progressive = options->Get(NanNew<String>("progressive"))->BooleanValue();
@@ -492,35 +707,54 @@ NAN_METHOD(resize) {
   baton->compressionLevel = options->Get(NanNew<String>("compressionLevel"))->Int32Value();
   baton->angle = options->Get(NanNew<String>("angle"))->Int32Value();
   // Output filename or __format for Buffer
-  baton->file_out = *String::Utf8Value(args[1]->ToString());
+  baton->output = *String::Utf8Value(options->Get(NanNew<String>("output"))->ToString());
 
   // Join queue for worker thread
-  NanCallback *callback = new NanCallback(args[2].As<v8::Function>());
+  NanCallback *callback = new NanCallback(args[1].As<v8::Function>());
   NanAsyncQueueWorker(new ResizeWorker(callback, baton));
 
-  // Increment queue length
-  g_atomic_int_inc(&queue_length);
+  // Increment queued task counter
+  g_atomic_int_inc(&counter_queue);
 
   NanReturnUndefined();
 }
 
+/*
+  Get and set cache memory and item limits
+*/
 NAN_METHOD(cache) {
   NanScope();
 
-  // Set cache limit
+  // Set cache memory limit
   if (args[0]->IsInt32()) {
     vips_cache_set_max_mem(args[0]->Int32Value() * 1048576);
   }
 
+  // Set cache items limit
+  if (args[1]->IsInt32()) {
+    vips_cache_set_max(args[1]->Int32Value());
+  }
+
   // 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>("limit"), NanNew<Number>(vips_cache_get_max_mem() / 1048576));
-  cache->Set(NanNew<String>("queue"), NanNew<Number>(queue_length));
+  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);
 }
 
+/*
+  Get internal counters (queued tasks, processing tasks)
+*/
+NAN_METHOD(counters) {
+  NanScope();
+  Local<Object> counters = NanNew<Object>();
+  counters->Set(NanNew<String>("queue"), NanNew<Number>(counter_queue));
+  counters->Set(NanNew<String>("process"), NanNew<Number>(counter_process));
+  NanReturnValue(counters);
+}
+
 static void at_exit(void* arg) {
   NanScope();
   vips_shutdown();
@@ -530,8 +764,14 @@ extern "C" void init(Handle<Object> target) {
   NanScope();
   vips_init("");
   AtExit(at_exit);
+  // Set libvips operation cache limits
+  vips_cache_set_max_mem(100 * 1048576); // 100 MB
+  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, "counters", counters);
 }
 
 NODE_MODULE(sharp, init)

tests/perf.js

@@ -142,6 +142,17 @@ async.series({
           }
         });
       }
+    }).add("sharp-stream-stream", {
+      defer: true,
+      fn: function(deferred) {
+        var readable = fs.createReadStream(inputJpg);
+        var writable = fs.createWriteStream(outputJpg);
+        writable.on('finish', function() {
+          deferred.resolve();
+        });
+        var pipeline = sharp().resize(width, height);
+        readable.pipe(pipeline).pipe(writable);
+      }
     }).add("sharp-file-buffer", {
       defer: true,
       fn: function(deferred) {
@@ -177,7 +188,7 @@ async.series({
     }).add("sharp-file-buffer-bicubic", {
       defer: true,
       fn: function(deferred) {
-        sharp(inputJpg).resize(width, height).bicubicInterpolation().toBuffer(function(err, buffer) {
+        sharp(inputJpg).resize(width, height).interpolateWith(sharp.interpolator.bicubic).toBuffer(function(err, buffer) {
           if (err) {
             throw err;
           } else {
@@ -189,7 +200,31 @@ async.series({
     }).add("sharp-file-buffer-nohalo", {
       defer: true,
       fn: function(deferred) {
-        sharp(inputJpg).resize(width, height).nohaloInterpolation().toBuffer(function(err, buffer) {
+        sharp(inputJpg).resize(width, height).interpolateWith(sharp.interpolator.nohalo).toBuffer(function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp-file-buffer-locallyBoundedBicubic", {
+      defer: true,
+      fn: function(deferred) {
+        sharp(inputJpg).resize(width, height).interpolateWith(sharp.interpolator.locallyBoundedBicubic).toBuffer(function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp-file-buffer-vertexSplitQuadraticBasisSpline", {
+      defer: true,
+      fn: function(deferred) {
+        sharp(inputJpg).resize(width, height).interpolateWith(sharp.interpolator.vertexSplitQuadraticBasisSpline).toBuffer(function(err, buffer) {
           if (err) {
             throw err;
           } else {

tests/unit.js

@@ -3,8 +3,8 @@
 'use strict';
 
 var sharp = require("../index");
+var fs = require("fs");
 var path = require("path");
-var imagemagick = require("imagemagick");
 var assert = require("assert");
 var async = require("async");
 
@@ -18,74 +18,72 @@ var outputTiff = path.join(fixturesPath, "output.tiff");
 
 var inputJpgWithExif = path.join(fixturesPath, "Landscape_8.jpg"); // https://github.com/recurser/exif-orientation-examples/blob/master/Landscape_8.jpg
 
+var inputPng = path.join(fixturesPath, "50020484-00001.png"); // http://c.searspartsdirect.com/lis_png/PLDM/50020484-00001.png
+var inputWebp = path.join(fixturesPath, "4.webp"); // http://www.gstatic.com/webp/gallery/4.webp
+var inputGif = path.join(fixturesPath, "Crash_test.gif"); // http://upload.wikimedia.org/wikipedia/commons/e/e3/Crash_test.gif
+
+// Ensure cache limits can be set
+sharp.cache(0); // Disable
+sharp.cache(50, 500); // 50MB, 500 items
+
 async.series([
   // Resize with exact crop
   function(done) {
-    sharp(inputJpg).resize(320, 240).toFile(outputJpg, function(err) {
+    sharp(inputJpg).resize(320, 240).toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(320, features.width);
-        assert.strictEqual(240, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(240, info.height);
+      done();
     });
   },
   // Resize to fixed width
   function(done) {
-    sharp(inputJpg).resize(320).toFile(outputJpg, function(err) {
+    sharp(inputJpg).resize(320).toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(320, features.width);
-        assert.strictEqual(261, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(261, info.height);
+      done();
     });
   },
   // Resize to fixed height
   function(done) {
-    sharp(inputJpg).resize(null, 320).toFile(outputJpg, function(err) {
+    sharp(inputJpg).resize(null, 320).toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(391, features.width);
-        assert.strictEqual(320, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(391, info.width);
+      assert.strictEqual(320, info.height);
+      done();
     });
   },
   // Identity transform
   function(done) {
-    sharp(inputJpg).toFile(outputJpg, function(err) {
+    sharp(inputJpg).toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(2725, features.width);
-        assert.strictEqual(2225, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(2725, info.width);
+      assert.strictEqual(2225, info.height);
+      done();
     });
   },
   // Upscale
   function(done) {
-    sharp(inputJpg).resize(3000).toFile(outputJpg, function(err) {
+    sharp(inputJpg).resize(3000).toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(3000, features.width);
-        assert.strictEqual(2449, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(3000, info.width);
+      assert.strictEqual(2449, info.height);
+      done();
     });
   },
   // Quality
   function(done) {
-    sharp(inputJpg).resize(320, 240).quality(70).jpeg(function(err, buffer70) {
+    sharp(inputJpg).resize(320, 240).quality(70).toBuffer(function(err, buffer70) {
       if (err) throw err;
-      sharp(inputJpg).resize(320, 240).jpeg(function(err, buffer80) {
+      sharp(inputJpg).resize(320, 240).toBuffer(function(err, buffer80) {
         if (err) throw err;
-        sharp(inputJpg).resize(320, 240).quality(90).jpeg(function(err, buffer90) {
+        sharp(inputJpg).resize(320, 240).quality(90).toBuffer(function(err, buffer90) {
           assert(buffer70.length < buffer80.length);
           assert(buffer80.length < buffer90.length);
           done();
@@ -95,61 +93,51 @@ async.series([
   },
   // TIFF with dimensions known to cause rounding errors
   function(done) {
-    sharp(inputTiff).resize(240, 320).embedBlack().toFile(outputJpg, function(err) {
+    sharp(inputTiff).resize(240, 320).embedBlack().jpeg().toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(240, features.width);
-        assert.strictEqual(320, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(240, info.width);
+      assert.strictEqual(320, info.height);
+      done();
     });
   },
   function(done) {
-    sharp(inputTiff).resize(240, 320).toFile(outputJpg, function(err) {
+    sharp(inputTiff).resize(240, 320).jpeg().toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(240, features.width);
-        assert.strictEqual(320, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(240, info.width);
+      assert.strictEqual(320, info.height);
+      done();
     });
   },
   // Resize to max width or height considering ratio (landscape)
   function(done) {
-    sharp(inputJpg).resize(320, 320).max().toFile(outputJpg, function(err) {
+    sharp(inputJpg).resize(320, 320).max().toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(320, features.width);
-        assert.strictEqual(261, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(261, info.height);
+      done();
     });
   },
   // Resize to max width or height considering ratio (portrait)
   function(done) {
-    sharp(inputTiff).resize(320, 320).max().toFile(outputJpg, function(err) {
+    sharp(inputTiff).resize(320, 320).max().jpeg().toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(243, features.width);
-        assert.strictEqual(320, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(243, info.width);
+      assert.strictEqual(320, info.height);
+      done();
     });
   },
   // Attempt to resize to max but only provide one dimension, so should default to crop
   function(done) {
-    sharp(inputJpg).resize(320).max().toFile(outputJpg, function(err) {
+    sharp(inputJpg).resize(320).max().toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(320, features.width);
-        assert.strictEqual(261, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(261, info.height);
+      done();
     });
   },
   // Attempt to output to input, should fail
@@ -161,50 +149,42 @@ async.series([
   },
   // Rotate by 90 degrees, respecting output input size
   function(done) {
-    sharp(inputJpg).rotate(90).resize(320, 240).toFile(outputJpg, function(err) {
+    sharp(inputJpg).rotate(90).resize(320, 240).toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(320, features.width);
-        assert.strictEqual(240, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(240, info.height);
+      done();
     });
   },
   // Input image has Orientation EXIF tag but do not rotate output
   function(done) {
-    sharp(inputJpgWithExif).resize(320).toFile(outputJpg, function(err) {
+    sharp(inputJpgWithExif).resize(320).toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(320, features.width);
-        assert.strictEqual(426, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(426, info.height);
+      done();
     });
   },
   // Input image has Orientation EXIF tag value of 8 (270 degrees), auto-rotate
   function(done) {
-    sharp(inputJpgWithExif).rotate().resize(320).toFile(outputJpg, function(err) {
+    sharp(inputJpgWithExif).rotate().resize(320).toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(320, features.width);
-        assert.strictEqual(240, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(240, info.height);
+      done();
     });
   },
   // Attempt to auto-rotate using image that has no EXIF
   function(done) {
-    sharp(inputJpg).rotate().resize(320).toFile(outputJpg, function(err) {
+    sharp(inputJpg).rotate().resize(320).toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(320, features.width);
-        assert.strictEqual(261, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(261, info.height);
+      done();
     });
   },
   // Rotate to an invalid angle, should fail
@@ -219,34 +199,32 @@ async.series([
   },
   // Do not enlarge the output if the input width is already less than the output width
   function(done) {
-    sharp(inputJpg).resize(2800).withoutEnlargement().toFile(outputJpg, function(err) {
+    sharp(inputJpg).resize(2800).withoutEnlargement().toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(2725, features.width);
-        assert.strictEqual(2225, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(2725, info.width);
+      assert.strictEqual(2225, info.height);
+      done();
     });
   },
   // Do not enlarge the output if the input height is already less than the output height
   function(done) {
-    sharp(inputJpg).resize(null, 2300).withoutEnlargement().toFile(outputJpg, function(err) {
+    sharp(inputJpg).resize(null, 2300).withoutEnlargement().toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(2725, features.width);
-        assert.strictEqual(2225, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(2725, info.width);
+      assert.strictEqual(2225, info.height);
+      done();
     });
   },
   // Promises/A+
   function(done) {
-    sharp(inputJpg).resize(320, 240).toFile(outputJpg).then(function() {
-      imagemagick.identify(outputJpg, function(err, features) {
-        assert.strictEqual(320, features.width);
-        assert.strictEqual(240, features.height);
+    sharp(inputJpg).resize(320, 240).toBuffer().then(function(data) {
+      sharp(data).toBuffer(function(err, data, info) {
+        if (err) throw err;
+        assert.strictEqual(true, data.length > 0);
+        assert.strictEqual(320, info.width);
+        assert.strictEqual(240, info.height);
         done();
       });
     }).catch(function(err) {
@@ -265,44 +243,307 @@ async.series([
   },
   // Check colour space conversion occurs from TIFF to WebP (this used to segfault)
   function(done) {
-    sharp(inputTiff).webp().then(function() {
+    sharp(inputTiff).webp().toBuffer().then(function() {
       done();
     });
   },
   // Interpolation: bilinear
   function(done) {
-    sharp(inputJpg).resize(320, 240).bilinearInterpolation().toFile(outputJpg, function(err) {
+    sharp(inputJpg).resize(320, 240).interpolateWith(sharp.interpolator.bilinear).toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(320, features.width);
-        assert.strictEqual(240, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(240, info.height);
+      done();
     });
   },
   // Interpolation: bicubic
   function(done) {
-    sharp(inputJpg).resize(320, 240).bicubicInterpolation().toFile(outputJpg, function(err) {
+    sharp(inputJpg).resize(320, 240).interpolateWith(sharp.interpolator.bicubic).toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
-        if (err) throw err;
-        assert.strictEqual(320, features.width);
-        assert.strictEqual(240, features.height);
-        done();
-      });
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(240, info.height);
+      done();
     });
   },
   // Interpolation: nohalo
   function(done) {
-    sharp(inputJpg).resize(320, 240).nohaloInterpolation().toFile(outputJpg, function(err) {
+    sharp(inputJpg).resize(320, 240).interpolateWith(sharp.interpolator.nohalo).toBuffer(function(err, data, info) {
       if (err) throw err;
-      imagemagick.identify(outputJpg, function(err, features) {
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(240, info.height);
+      done();
+    });
+  },
+  // Interpolation: locally bounded bicubic (LBB)
+  function(done) {
+    sharp(inputJpg).resize(320, 240).interpolateWith(sharp.interpolator.locallyBoundedBicubic).toBuffer(function(err, data, info) {
+      if (err) throw err;
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(240, info.height);
+      done();
+    });
+  },
+  // Interpolation: vertex split quadratic basis spline (VSQBS)
+  function(done) {
+    sharp(inputJpg).resize(320, 240).interpolateWith(sharp.interpolator.vertexSplitQuadraticBasisSpline).toBuffer(function(err, data, info) {
+      if (err) throw err;
+      assert.strictEqual(true, data.length > 0);
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(240, info.height);
+      done();
+    });
+  },
+  // File-Stream
+  function(done) {
+    var writable = fs.createWriteStream(outputJpg);
+    writable.on('finish', function() {
+      sharp(outputJpg).toBuffer(function(err, data, info) {
         if (err) throw err;
-        assert.strictEqual(320, features.width);
-        assert.strictEqual(240, features.height);
+        assert.strictEqual(true, data.length > 0);
+        assert.strictEqual(320, info.width);
+        assert.strictEqual(240, info.height);
+        fs.unlinkSync(outputJpg);
+        done();
+      });
+    });
+    sharp(inputJpg).resize(320, 240).pipe(writable);
+  },
+  // Buffer-Stream
+  function(done) {
+    var inputJpgBuffer = fs.readFileSync(inputJpg);
+    var writable = fs.createWriteStream(outputJpg);
+    writable.on('finish', function() {
+      sharp(outputJpg).toBuffer(function(err, data, info) {
+        if (err) throw err;
+        assert.strictEqual(true, data.length > 0);
+        assert.strictEqual(320, info.width);
+        assert.strictEqual(240, info.height);
+        fs.unlinkSync(outputJpg);
+        done();
+      });
+    });
+    sharp(inputJpgBuffer).resize(320, 240).pipe(writable);
+  },
+  // Stream-File
+  function(done) {
+    var readable = fs.createReadStream(inputJpg);
+    var pipeline = sharp().resize(320, 240).toFile(outputJpg, function(err, info) {
+      if (err) throw err;
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(240, info.height);
+      fs.unlinkSync(outputJpg);
+      done();
+    });
+    readable.pipe(pipeline);
+  },
+  // Stream-Buffer
+  function(done) {
+    var readable = fs.createReadStream(inputJpg);
+    var pipeline = sharp().resize(320, 240).toBuffer(function(err, data, info) {
+      if (err) throw err;
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(240, info.height);
+      done();
+    });
+    readable.pipe(pipeline);
+  },
+  // Stream-Stream
+  function(done) {
+    var readable = fs.createReadStream(inputJpg);
+    var writable = fs.createWriteStream(outputJpg);
+    writable.on('finish', function() {
+      sharp(outputJpg).toBuffer(function(err, data, info) {
+        if (err) throw err;
+        assert.strictEqual(true, data.length > 0);
+        assert.strictEqual(320, info.width);
+        assert.strictEqual(240, info.height);
+        fs.unlinkSync(outputJpg);
+        done();
+      });
+    });
+    var pipeline = sharp().resize(320, 240);
+    readable.pipe(pipeline).pipe(writable);
+  },
+  // Crop, gravity=north
+  function(done) {
+    sharp(inputJpg).resize(320, 80).crop(sharp.gravity.north).toFile(path.join(fixturesPath, 'output.gravity-north.jpg'), function(err, info) {
+      if (err) throw err;
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(80, info.height);
+      done();
+    });
+  },
+  // Crop, gravity=east
+  function(done) {
+    sharp(inputJpg).resize(80, 320).crop(sharp.gravity.east).toFile(path.join(fixturesPath, 'output.gravity-east.jpg'), function(err, info) {
+      if (err) throw err;
+      assert.strictEqual(80, info.width);
+      assert.strictEqual(320, info.height);
+      done();
+    });
+  },
+  // Crop, gravity=south
+  function(done) {
+    sharp(inputJpg).resize(320, 80).crop(sharp.gravity.south).toFile(path.join(fixturesPath, 'output.gravity-south.jpg'), function(err, info) {
+      if (err) throw err;
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(80, info.height);
+      done();
+    });
+  },
+  // Crop, gravity=west
+  function(done) {
+    sharp(inputJpg).resize(80, 320).crop(sharp.gravity.west).toFile(path.join(fixturesPath, 'output.gravity-west.jpg'), function(err, info) {
+      if (err) throw err;
+      assert.strictEqual(80, info.width);
+      assert.strictEqual(320, info.height);
+      done();
+    });
+  },
+  // Crop, gravity=center
+  function(done) {
+    sharp(inputJpg).resize(320, 80).crop(sharp.gravity.center).toFile(path.join(fixturesPath, 'output.gravity-center.jpg'), function(err, info) {
+      if (err) throw err;
+      assert.strictEqual(320, info.width);
+      assert.strictEqual(80, info.height);
+      done();
+    });
+  },
+  // Crop, gravity=centre
+  function(done) {
+    sharp(inputJpg).resize(80, 320).crop(sharp.gravity.centre).toFile(path.join(fixturesPath, 'output.gravity-centre.jpg'), function(err, info) {
+      if (err) throw err;
+      assert.strictEqual(80, info.width);
+      assert.strictEqual(320, info.height);
+      done();
+    });
+  },
+  // Metadata - JPEG
+  function(done) {
+    sharp(inputJpg).metadata(function(err, metadata) {
+      if (err) throw err;
+      assert.strictEqual('jpeg', metadata.format);
+      assert.strictEqual(2725, metadata.width);
+      assert.strictEqual(2225, metadata.height);
+      assert.strictEqual('srgb', metadata.space);
+      assert.strictEqual(3, metadata.channels);
+      assert.strictEqual('undefined', typeof metadata.orientation);
+      done();
+    });
+  },
+  // Metadata - JPEG with EXIF
+  function(done) {
+    sharp(inputJpgWithExif).metadata(function(err, metadata) {
+      if (err) throw err;
+      assert.strictEqual('jpeg', metadata.format);
+      assert.strictEqual(450, metadata.width);
+      assert.strictEqual(600, metadata.height);
+      assert.strictEqual('srgb', metadata.space);
+      assert.strictEqual(3, metadata.channels);
+      assert.strictEqual(8, metadata.orientation);
+      done();
+    });
+  },
+  // Metadata - TIFF
+  function(done) {
+    sharp(inputTiff).metadata(function(err, metadata) {
+      if (err) throw err;
+      assert.strictEqual('tiff', metadata.format);
+      assert.strictEqual(2464, metadata.width);
+      assert.strictEqual(3248, metadata.height);
+      assert.strictEqual('b-w', metadata.space);
+      assert.strictEqual(1, metadata.channels);
+      done();
+    });
+  },
+  // Metadata - PNG
+  function(done) {
+    sharp(inputPng).metadata(function(err, metadata) {
+      if (err) throw err;
+      assert.strictEqual('png', metadata.format);
+      assert.strictEqual(2809, metadata.width);
+      assert.strictEqual(2074, metadata.height);
+      assert.strictEqual('b-w', metadata.space);
+      assert.strictEqual(1, metadata.channels);
+      done();
+    });
+  },
+  // Metadata - WebP
+  function(done) {
+    sharp(inputWebp).metadata(function(err, metadata) {
+      if (err) throw err;
+      assert.strictEqual('webp', metadata.format);
+      assert.strictEqual(1024, metadata.width);
+      assert.strictEqual(772, metadata.height);
+      assert.strictEqual('srgb', metadata.space);
+      assert.strictEqual(3, metadata.channels);
+      done();
+    });
+  },
+  // Metadata - GIF (via libmagick)
+  function(done) {
+    sharp(inputGif).metadata(function(err, metadata) {
+      if (err) throw err;
+      assert.strictEqual('magick', metadata.format);
+      assert.strictEqual(800, metadata.width);
+      assert.strictEqual(533, metadata.height);
+      assert.strictEqual(3, metadata.channels);
+      done();
+    });
+  },
+  // Metadata - Promise
+  function(done) {
+    sharp(inputJpg).metadata().then(function(metadata) {
+      assert.strictEqual('jpeg', metadata.format);
+      assert.strictEqual(2725, metadata.width);
+      assert.strictEqual(2225, metadata.height);
+      assert.strictEqual('srgb', metadata.space);
+      assert.strictEqual(3, metadata.channels);
+      done();
+    });
+  },
+  // Metadata - Stream
+  function(done) {
+    var readable = fs.createReadStream(inputJpg);
+    var pipeline = sharp().metadata(function(err, metadata) {
+      if (err) throw err;
+      assert.strictEqual('jpeg', metadata.format);
+      assert.strictEqual(2725, metadata.width);
+      assert.strictEqual(2225, metadata.height);
+      assert.strictEqual('srgb', metadata.space);
+      assert.strictEqual(3, metadata.channels);
+      done();
+    });
+    readable.pipe(pipeline);
+  },
+  // Get metadata then resize to half width
+  function(done) {
+    var image = sharp(inputJpg);
+    image.metadata(function(err, metadata) {
+      if (err) throw err;
+      assert.strictEqual('jpeg', metadata.format);
+      assert.strictEqual(2725, metadata.width);
+      assert.strictEqual(2225, metadata.height);
+      assert.strictEqual('srgb', metadata.space);
+      assert.strictEqual(3, metadata.channels);
+      image.resize(metadata.width / 2).toBuffer(function(err, data, info) {
+        if (err) throw err;
+        assert.strictEqual(true, data.length > 0);
+        assert.strictEqual(1362, info.width);
+        assert.strictEqual(1112, info.height);
         done();
       });
     });
   },
+  // Verify internal counters
+  function(done) {
+    var counters = sharp.counters();
+    assert.strictEqual(0, counters.queue);
+    assert.strictEqual(0, counters.process);
+    done();
+  }
 ]);