Take a temporary copy of buffers provided as input. Soak testing suggests this prevents the problems seen in #6.

README.md

@@ -1,4 +1,4 @@
-# sharp
+# sharp
 
 _adj_
 
@@ -9,26 +9,16 @@ _adj_
 
 The typical use case for this high speed Node.js module is to convert large JPEG and PNG images to smaller JPEG and PNG images of varying dimensions.
 
-It is somewhat opinionated in that it only deals with JPEG and PNG images, always obeys the requested dimensions by either cropping or embedding and insists on a mild sharpen of the resulting image.
+The performance of JPEG resizing is typically 15x-25x faster than ImageMagick and GraphicsMagick, based mainly on the number of CPU cores available.
 
-Under the hood you'll find the blazingly fast [libvips](https://github.com/jcupitt/libvips) image processing library, originally created in 1989 at Birkbeck College and currently maintained by the University of Southampton.
+Under the hood you'll find 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.
-
-Performance is 4x-8x faster than ImageMagick and 2x-4x faster than GraphicsMagick, based mainly on the number of CPU cores available.
 
 ## Prerequisites
 
 * Node.js v0.8+
-* node-gyp
+* [libvips](https://github.com/jcupitt/libvips) v7.38+
-* libvips-dev 7.28+ (7.36+ for optimal JPEG Huffman coding)
 
-```
+For the sharpest results, please compile libvips from source.
-sudo npm install -g node-gyp
-sudo apt-get install libvips-dev
-```
-
-When installed as a package, please symlink `vips-7.28.pc` (or later, installed with libvips-dev) as `/usr/lib/pkgconfig/vips.pc`. To do this in Ubuntu 13.04 (64-bit), use:
-
-	sudo ln -s /usr/lib/x86_64-linux-gnu/pkgconfig/vips-7.28.pc /usr/lib/pkgconfig/vips.pc
 
 ## Install
 
@@ -38,14 +28,31 @@ When installed as a package, please symlink `vips-7.28.pc` (or later, installed
 
 	var sharp = require("sharp");
 
-### crop(inputPath, outputPath, width, height, callback)
+### resize(input, output, width, height, [options], callback)
 
-Scale and crop `inputPath` to `width` x `height` and write to `outputPath` calling `callback` when complete.
+Scale and crop to `width` x `height` calling `callback` when complete.
 
-Example:
+`input` can either be a filename String or a Buffer. When using a filename libvips will `mmap` the file for improved performance. 
+
+`output` can either be a filename String or one of `sharp.buffer.jpeg` or `sharp.buffer.png` to pass a Buffer containing image data to `callback`.
+
+`width` is the Number of pixels wide the resultant image should be.
+
+`height` is the Number of pixels high the resultant image should be.
+
+`options` is optional, and can contain one or more of:
+
+* `canvas` can be one of `sharp.canvas.crop`, `sharp.canvas.embedWhite` or `sharp.canvas.embedBlack`. Defaults to `sharp.canvas.crop`.
+* `sharpen` when set to true will perform a mild sharpen of the resultant image. This typically reduces performance by 30%.
+* `progressive` when set will use progressive (interlace) scan for the output. This typically reduces performance by 30%.
+* `sequentialRead` is an advanced setting that, when set, switches the libvips access method to `VIPS_ACCESS_SEQUENTIAL`. This will reduce memory usage and can improve performance on some systems.
+
+`callback` gets two arguments `(err, buffer)` where `err` is an error message, if any, and `buffer` is the resultant image data when a Buffer is requested.
+
+### Examples
 
 ```javascript
-sharp.crop("input.jpg", "output.jpg", 300, 200, function(err) {
+sharp.resize("input.jpg", "output.jpg", 300, 200, function(err) {
   if (err) {
     throw err;
   }
@@ -54,37 +61,46 @@ sharp.crop("input.jpg", "output.jpg", 300, 200, function(err) {
 });
 ```
 
-### embedWhite(inputPath, outputPath, width, height, callback)
-
-Scale and embed `inputPath` to `width` x `height` using a white canvas and write to `outputPath` calling `callback` when complete.
-
 ```javascript
-sharp.embedWhite("input.jpg", "output.png", 200, 300, function(err) {
+sharp.resize("input.jpg", sharp.buffer.jpeg, 300, 200, {progressive: true}, function(err, buffer) {
   if (err) {
     throw err;
   }
-  // output.jpg is a 200 pixels wide and 300 pixels high image
+  // buffer contains progressive JPEG image data
-  // containing a scaled version of input.png embedded on a white canvas
 });
 ```
 
-### embedBlack(inputPath, outputPath, width, height, callback)
-
-Scale and embed `inputPath` to `width` x `height` using a black canvas and write to `outputPath` calling `callback` when complete.
-
 ```javascript
-sharp.embedBlack("input.png", "output.png", 200, 300, function(err) {
+sharp.resize("input.jpg", sharp.buffer.png, 300, 200, {sharpen: true}, function(err, buffer) {
   if (err) {
     throw err;
   }
-  // output.png is a 200 pixels wide and 300 pixels high image
+  // buffer contains sharpened PNG image data (converted from JPEG)
+});
+```
+
+```javascript
+sharp.resize(buffer, "output.jpg", 200, 300, {canvas: sharp.canvas.embedWhite}, function(err) {
+  if (err) {
+    throw err;
+  }
+  // output.jpg is a 200 pixels wide and 300 pixels high image containing a scaled version
+  // of the image data contained in buffer embedded on a white canvas
+});
+```
+
+```javascript
+sharp.resize("input.jpg", sharp.buffer.jpeg, 200, 300, {canvas: sharp.canvas.embedBlack}, function(err, buffer) {
+  if (err) {
+    throw err;
+  }
+  // buffer contains JPEG image data of a 200 pixels wide and 300 pixels high image
   // containing a scaled version of input.png embedded on a black canvas
 });
 ```
 
 ## Testing
 
-	npm install --dev sharp
 	npm test
 
 ## Performance
@@ -92,27 +108,50 @@ sharp.embedBlack("input.png", "output.png", 200, 300, function(err) {
 Test environment:
 
 * AMD Athlon 4 core 3.3GHz 512KB L2 CPU 1333 DDR3
-* libvips 7.36
+* libvips 7.37
-* libjpeg-turbo8 1.2.1
+* libjpeg-turbo8 1.3.0
 * libpng 1.6.6
 * zlib1g 1.2.7
 
-#### JPEG
+`-file-buffer` indicates read from file and write to buffer, `-buffer-file` indicates read from buffer and write to file etc.
 
-* imagemagick x 5.53 ops/sec ±0.55% (31 runs sampled)
+`-sharpen`, `-progressive` etc. demonstrate the negative effect of options on performance.
-* gm x 10.86 ops/sec ±0.43% (56 runs sampled)
-* epeg x 28.07 ops/sec ±0.07% (70 runs sampled)
-* sharp x 31.60 ops/sec ±8.80% (80 runs sampled)
 
-#### PNG
+### JPEG
 
-* imagemagick x 4.65 ops/sec ±0.37% (27 runs sampled)
+* imagemagick x 5.53 ops/sec ±0.62% (31 runs sampled)
-* gm x 21.65 ops/sec ±0.18% (56 runs sampled)
+* gm-file-file x 4.10 ops/sec ±0.41% (25 runs sampled)
-* sharp x 39.47 ops/sec ±6.78% (68 runs sampled)
+* gm-file-buffer x 4.10 ops/sec ±0.36% (25 runs sampled)
+* epeg-file-file x 23.82 ops/sec ±0.18% (60 runs sampled)
+* epeg-file-buffer x 23.98 ops/sec ±0.16% (61 runs sampled)
+
+* sharp-buffer-file x 20.76 ops/sec ±0.55% (54 runs sampled)
+* sharp-buffer-buffer x 20.90 ops/sec ±0.26% (54 runs sampled)
+* sharp-file-file x 91.78 ops/sec ±0.38% (88 runs sampled)
+* sharp-file-buffer x __93.05 ops/sec__ ±0.61% (76 runs sampled)
+
+* sharp-file-buffer-sharpen x 63.09 ops/sec ±5.58% (63 runs sampled)
+* sharp-file-buffer-progressive x 61.68 ops/sec ±0.53% (76 runs sampled)
+* sharp-file-buffer-sequentialRead x 60.66 ops/sec ±0.38% (75 runs sampled)
+
+### PNG
+
+* imagemagick x 4.27 ops/sec ±0.21% (25 runs sampled)
+* gm-file-file x 8.33 ops/sec ±0.19% (44 runs sampled)
+* gm-file-buffer x 7.45 ops/sec ±0.16% (40 runs sampled)
+ 
+* sharp-buffer-file x 4.94 ops/sec ±118.46% (26 runs sampled)
+* sharp-buffer-buffer x 12.59 ops/sec ±0.55% (64 runs sampled)
+* sharp-file-file x 44.06 ops/sec ±6.86% (75 runs sampled)
+* sharp-file-buffer x __46.29 ops/sec__ ±0.38% (76 runs sampled)
+
+* sharp-file-buffer-sharpen x 38.86 ops/sec ±0.22% (65 runs sampled)
+* sharp-file-buffer-progressive x 46.35 ops/sec ±0.20% (76 runs sampled)
+* sharp-file-buffer-sequentialRead x 29.02 ops/sec ±0.62% (72 runs sampled)
 
 ## Licence
 
-Copyright 2013 Lovell Fuller
+Copyright 2013, 2014 Lovell Fuller
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.

binding.gyp

@@ -7,11 +7,13 @@
       '<!@(PKG_CONFIG_PATH="/usr/lib/pkgconfig" pkg-config --libs vips)'
     ],
     'include_dirs': [
+      '/usr/local/include/glib-2.0',
+      '/usr/local/lib/glib-2.0/include',
       '/usr/include/glib-2.0',
       '/usr/lib/glib-2.0/include',
       '/usr/lib/x86_64-linux-gnu/glib-2.0/include'
     ],
-    'cflags': ['-fexceptions'],
+    'cflags': ['-fexceptions', '-pedantic', '-Wall', '-O3'],
-    'cflags_cc': ['-fexceptions']
+    'cflags_cc': ['-fexceptions', '-pedantic', '-Wall', '-O3']
   }]
 }

index.js

@@ -1,13 +1,64 @@
 var sharp = require("./build/Release/sharp");
 
-module.exports.crop = function(input, output, width, height, callback) {
+module.exports.buffer = {
-  sharp.resize(input, output, width, height, "c", callback);
+  jpeg: "__jpeg",
+  png: "__png"
 };
 
+module.exports.canvas = {
+  crop: "c",
+  embedWhite: "w",
+  embedBlack: "b"
+};
+
+module.exports.resize = function(input, output, width, height, options, callback) {
+  "use strict";
+  if (typeof options === 'function') {
+    callback = options;
+    options = {};
+  } else {
+    options = options || {};
+  }
+  if (typeof input === 'string') {
+    options.inFile = input;
+  } else if (typeof input ==='object' && input instanceof Buffer) {
+    options.inBuffer = input;
+  } else {
+    callback("Unsupported input " + typeof input);
+    return;
+  }
+  if (!output || output.length === 0) {
+    callback("Invalid output");
+    return;
+  }
+  var outWidth = Number(width);
+  if (Number.isNaN(outWidth)) {
+    callback("Invalid width " + width);
+    return;
+  }
+  var outHeight = Number(height);
+  if (Number.isNaN(outHeight)) {
+    callback("Invalid height " + height);
+    return;
+  }
+  var canvas = options.canvas || "c";
+  if (canvas.length !== 1 || "cwb".indexOf(canvas) === -1) {
+    callback("Invalid canvas " + canvas);
+    return;
+  }
+  var sharpen = !!options.sharpen;
+  var progessive = !!options.progessive;
+  var sequentialRead = !!options.sequentialRead;
+  sharp.resize(options.inFile, options.inBuffer, output, width, height, canvas, sharpen, progessive, sequentialRead, callback);
+};
+
+/* Deprecated v0.0.x methods */
+module.exports.crop = function(input, output, width, height, sharpen, callback) {
+  sharp.resize(input, output, width, height, {canvas: "c", sharpen: true}, callback);
+};
 module.exports.embedWhite = function(input, output, width, height, callback) {
-  sharp.resize(input, output, width, height, "w", callback);
+  sharp.resize(input, output, width, height, {canvas: "w", sharpen: true}, callback);
 };
-
 module.exports.embedBlack = function(input, output, width, height, callback) {
-  sharp.resize(input, output, width, height, "b", callback);
+  sharp.resize(input, output, width, height, {canvas: "b", sharpen: true}, callback);
 };

package.json

@@ -1,6 +1,6 @@
 {
   "name": "sharp",
-  "version": "0.0.5",
+  "version": "0.1.5",
   "author": "Lovell Fuller",
   "description": "High performance module to resize JPEG and PNG images using the libvips image processing library",
   "scripts": {
@@ -20,7 +20,8 @@
     "crop",
     "embed",
     "libvips",
-    "fast"
+    "fast",
+    "buffer"
   ],
   "devDependencies": {
     "imagemagick": "*",

src/sharp.cc

@@ -1,193 +1,302 @@
 #include <node.h>
+#include <node_buffer.h>
 #include <math.h>
 #include <string>
-#include <vector>
+#include <string.h>
 #include <vips/vips.h>
 
 using namespace v8;
+using namespace node;
 
-// Free VipsImage children when object goes out of scope
+struct resize_baton {
-// Thanks due to https://github.com/dosx/node-vips
+  std::string file_in;
-class ImageFreer {
+  void* buffer_in;
-  public:
+  size_t buffer_in_len;
-    ImageFreer() {}
+  std::string file_out;
-    ~ImageFreer() {
+  void* buffer_out;
-      for (uint16_t i = 0; i < v_.size(); i++) {
+  size_t buffer_out_len;
-        if (v_[i] != NULL) {
+  int  width;
-          g_object_unref(v_[i]);
+  int  height;
-        }
-      }
-      v_.clear();
-    }
-    void add(VipsImage* i) { v_.push_back(i); }
-  private:
-    std::vector<VipsImage*> v_;
-};
-
-struct ResizeBaton {
-  std::string src;
-  std::string dst;
-  int  cols;
-  int  rows;
   bool crop;
-  int  embed;
+  VipsExtend extend;
+  bool sharpen;
+  bool progessive;
+  VipsAccess access_method;
   std::string err;
   Persistent<Function> callback;
+
+  resize_baton(): buffer_in_len(0), buffer_out_len(0) {}
 };
 
-bool EndsWith(std::string const &str, std::string const &end) {
+typedef enum {
+  JPEG,
+  PNG
+} ImageType;
+
+unsigned char MARKER_JPEG[] = {0xff, 0xd8};
+unsigned char MARKER_PNG[] = {0x89, 0x50};
+
+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);
 }
 
-void ResizeAsync(uv_work_t *work) {
+bool is_jpeg(std::string const &str) {
-  ResizeBaton* baton = static_cast<ResizeBaton*>(work->data);
+  return ends_with(str, ".jpg") || ends_with(str, ".jpeg");
+}
 
-  VipsImage *in = vips_image_new_mode((baton->src).c_str(), "p");
+bool is_png(std::string const &str) {
-  if (EndsWith(baton->src, ".jpg") || EndsWith(baton->src, ".jpeg"))  {
+  return ends_with(str, ".png");
-    vips_jpegload((baton->src).c_str(), &in, NULL);
+}
-  } else if (EndsWith(baton->src, ".png")) {
+
-    vips_pngload((baton->src).c_str(), &in, NULL);
+void resize_error(resize_baton *baton, VipsImage *unref) {
+  (baton->err).append(vips_error_buffer());
+  vips_error_clear();
+  g_object_unref(unref);
+  vips_thread_shutdown();
+  return;
+}
+
+void resize_async(uv_work_t *work) {
+  resize_baton* baton = static_cast<resize_baton*>(work->data);
+
+  ImageType inputImageType = JPEG;
+  VipsImage *in = 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 (is_jpeg(baton->file_in)) {
+    if (vips_jpegload((baton->file_in).c_str(), &in, "access", baton->access_method, NULL)) {
+      return resize_error(baton, in);
+    }
+  } else if (is_png(baton->file_in)) {
+    inputImageType = PNG;
+    if (vips_pngload((baton->file_in).c_str(), &in, "access", baton->access_method, NULL)) {
+      return resize_error(baton, in);
+    }
   } else {
-    (baton->err).append("Unsupported input file type");
+    resize_error(baton, in);
-    return;
+    (baton->err).append("Unsupported input " + baton->file_in);
-  }
-  if (in == NULL) {
-    (baton->err).append(vips_error_buffer());
-    vips_error_clear();
-    return;
-  }
-  ImageFreer freer;
-  freer.add(in);
-
-  VipsImage* img = in;
-  VipsImage* t[4];
-
-  if (im_open_local_array(img, t, 4, "temp", "p")) {
-    (baton->err).append(vips_error_buffer());
-    vips_error_clear();
     return;
   }
 
-  double xfactor = static_cast<double>(img->Xsize) / std::max(baton->cols, 1);
+  double xfactor = static_cast<double>(in->Xsize) / std::max(baton->width, 1);
-  double yfactor = static_cast<double>(img->Ysize) / std::max(baton->rows, 1);
+  double yfactor = static_cast<double>(in->Ysize) / std::max(baton->height, 1);
   double factor = baton->crop ? std::min(xfactor, yfactor) : std::max(xfactor, yfactor);
   factor = std::max(factor, 1.0);
   int shrink = floor(factor);
   double residual = shrink / factor;
 
-  // Use im_shrink with the integral reduction
+  // Try to use libjpeg shrink-on-load
-  if (im_shrink(img, t[0], shrink, shrink)) {
+  int shrink_on_load = 1;
-    (baton->err).append(vips_error_buffer());
+  if (inputImageType == JPEG) {
-    vips_error_clear();
+    if (shrink >= 8) {
-    return;
+      factor = factor / 8;
-  }
+      shrink_on_load = 8;
-
+    } else if (shrink >= 4) {
-  // Use im_affinei with the remaining float part using bilinear interpolation
+      factor = factor / 4;
-  if (im_affinei_all(t[0], t[1], vips_interpolate_bilinear_static(), residual, 0, 0, residual, 0, 0)) {
+      shrink_on_load = 4;
-    (baton->err).append(vips_error_buffer());
+    } else if (shrink >= 2) {
-    vips_error_clear();
+      factor = factor / 2;
-    return;
+      shrink_on_load = 2;
-  }
+    }
-  img = t[1];
+  }
-
+  VipsImage *shrunk_on_load = vips_image_new();
-  if (baton->crop) {
+  if (shrink_on_load > 1) {
-    int width = std::min(img->Xsize, baton->cols);
+    // Recalculate integral shrink and double residual
-    int height = std::min(img->Ysize, baton->rows);
+    factor = std::max(factor, 1.0);
-    int left = (img->Xsize - width + 1) / 2;
+    shrink = floor(factor);
-    int top = (img->Ysize - height + 1) / 2;
+    residual = shrink / factor;
-    if (im_extract_area(img, t[2], left, top, width, height)) {
+    // Reload input using shrink-on-load 
-      (baton->err).append(vips_error_buffer());
+    if (baton->buffer_in_len > 1) {
-      vips_error_clear();
+      if (vips_jpegload_buffer(baton->buffer_in, baton->buffer_in_len, &shrunk_on_load, "shrink", shrink_on_load, NULL)) {
-      return;
+        return resize_error(baton, in);
+      }
+    } else {
+      if (vips_jpegload((baton->file_in).c_str(), &shrunk_on_load, "shrink", shrink_on_load, NULL)) {
+        return resize_error(baton, in);
+      }
     }
-    img = t[2];
   } else {
-    int left = (baton->cols - img->Xsize) / 2;
+    vips_copy(in, &shrunk_on_load, NULL);
-    int top = (baton->rows - img->Ysize) / 2;
-    if (im_embed(img, t[2], baton->embed, left, top, baton->cols, baton->rows)) {
-      (baton->err).append(vips_error_buffer());
-      vips_error_clear();
-      return;
-    }
-    img = t[2];
   }
+  g_object_unref(in);
+
+  VipsImage *shrunk = vips_image_new();
+  if (shrink > 1) {
+    // Use vips_shrink with the integral reduction
+    if (vips_shrink(shrunk_on_load, &shrunk, shrink, shrink, NULL)) {
+      return resize_error(baton, shrunk_on_load);
+    }
+  } else {
+    vips_copy(shrunk_on_load, &shrunk, NULL);
+  }
+  g_object_unref(shrunk_on_load);
+
+  // Use vips_affine with the remaining float part using bilinear interpolation
+  VipsImage *affined = vips_image_new();
+  if (residual > 0) {
+    if (vips_affine(shrunk, &affined, residual, 0, 0, residual, "interpolate", vips_interpolate_bilinear_static(), NULL)) {
+      return resize_error(baton, shrunk);
+    }
+  } else {
+    vips_copy(shrunk, &affined, NULL);
+  }
+  g_object_unref(shrunk);
+
+  VipsImage *canvased = vips_image_new();
+  if (affined->Xsize != baton->width || affined->Ysize != baton->height) {
+    if (baton->crop) {
+      // Crop
+      int width = std::min(affined->Xsize, baton->width);
+      int height = std::min(affined->Ysize, baton->height);
+      int left = (affined->Xsize - width + 1) / 2;
+      int top = (affined->Ysize - height + 1) / 2;
+      if (vips_extract_area(affined, &canvased, left, top, width, height, NULL)) {
+        return resize_error(baton, affined);
+      }
+    } else {
+      // Embed
+      int left = (baton->width - affined->Xsize) / 2;
+      int top = (baton->height - affined->Ysize) / 2;
+      if (vips_embed(affined, &canvased, left, top, baton->width, baton->height, "extend", baton->extend, NULL)) {
+        return resize_error(baton, affined);
+      }
+    }
+  } else {
+    vips_copy(affined, &canvased, NULL);
+  }
+  g_object_unref(affined);
 
   // Mild sharpen
-  INTMASK* sharpen = im_create_imaskv("sharpen", 3, 3,
+  VipsImage *sharpened = vips_image_new();
-    -1, -1, -1,
+  if (baton->sharpen) {
-    -1, 32, -1,
+    INTMASK* sharpen = im_create_imaskv("sharpen", 3, 3,
-    -1, -1, -1);
+      -1, -1, -1,
-  sharpen->scale = 24;
+      -1, 32, -1,
-  if (im_conv(img, t[3], sharpen)) { 
+      -1, -1, -1);
-    (baton->err).append(vips_error_buffer());
+    sharpen->scale = 24;
-    vips_error_clear();
+    if (im_conv(canvased, sharpened, sharpen)) {
-    return;
+      return resize_error(baton, canvased);
-  }
-  img = t[3];
-
-  if (EndsWith(baton->dst, ".jpg") || EndsWith(baton->dst, ".jpeg"))  {
-    if (vips_jpegsave(img, baton->dst.c_str(), "Q", 80, "profile", "none", "optimize_coding", TRUE, NULL)) {
-      (baton->err).append(vips_error_buffer());
-      vips_error_clear();
-    }
-  } else if (EndsWith(baton->dst, ".png")) {
-    if (vips_pngsave(img, baton->dst.c_str(), "compression", 6, "interlace", FALSE, NULL)) {
-      (baton->err).append(vips_error_buffer());
-      vips_error_clear();
     }
   } else {
-    (baton->err).append("Unsupported output file type");
+    vips_copy(canvased, &sharpened, NULL);
   }
+  g_object_unref(canvased);
+
+  if (baton->file_out == "__jpeg") {
+    // Write JPEG to buffer
+    if (vips_jpegsave_buffer(sharpened, &baton->buffer_out, &baton->buffer_out_len, "strip", TRUE, "Q", 80, "optimize_coding", TRUE, "interlace", baton->progessive, NULL)) {
+      return resize_error(baton, sharpened);
+    }
+  } else if (baton->file_out == "__png") {
+    // Write PNG to buffer
+    if (vips_pngsave_buffer(sharpened, &baton->buffer_out, &baton->buffer_out_len, "strip", TRUE, "compression", 6, "interlace", baton->progessive, NULL)) {
+      return resize_error(baton, sharpened);
+    }
+  } else if (is_jpeg(baton->file_out))  {
+    // Write JPEG to file
+    if (vips_jpegsave(sharpened, baton->file_out.c_str(), "strip", TRUE, "Q", 80, "optimize_coding", TRUE, "interlace", baton->progessive, NULL)) {
+      return resize_error(baton, sharpened);
+    }
+  } else if (is_png(baton->file_out)) {
+    // Write PNG to file
+    if (vips_pngsave(sharpened, baton->file_out.c_str(), "strip", TRUE, "compression", 6, "interlace", baton->progessive, NULL)) {
+      return resize_error(baton, sharpened);
+    }
+  } else {
+    (baton->err).append("Unsupported output " + baton->file_out);
+  }
+  g_object_unref(sharpened);
+  vips_thread_shutdown();
 }
 
-void ResizeAsyncAfter(uv_work_t *work, int status) {
+void resize_async_after(uv_work_t *work, int status) {
   HandleScope scope;
 
-  ResizeBaton *baton = static_cast<ResizeBaton*>(work->data);
+  resize_baton *baton = static_cast<resize_baton*>(work->data);
 
-  Local<Value> argv[1];
+  // Free temporary copy of input buffer
-  if (!baton->err.empty()) {
+  if (baton->buffer_in_len > 0) {
-    argv[0] = String::New(baton->err.data(), baton->err.size());
+    g_free(baton->buffer_in);
-  } else {
-    argv[0] = Local<Value>::New(Null());
   }
 
-  baton->callback->Call(Context::GetCurrent()->Global(), 1, argv);
+  Handle<Value> argv[2] = { Null(), Null() };
+  if (!baton->err.empty()) {
+    // Error
+    argv[0] = scope.Close(String::New(baton->err.data(), baton->err.size()));
+  } else if (baton->buffer_out_len > 0) {
+    // Buffer
+    Buffer *slowBuffer = Buffer::New(baton->buffer_out_len);
+    memcpy(Buffer::Data(slowBuffer), baton->buffer_out, baton->buffer_out_len);
+    Local<Object> globalObj = Context::GetCurrent()->Global();
+    Local<Function> bufferConstructor = Local<Function>::Cast(globalObj->Get(String::New("Buffer")));
+    Handle<Value> constructorArgs[3] = { slowBuffer->handle_, v8::Integer::New(baton->buffer_out_len), v8::Integer::New(0) };
+    argv[1] = scope.Close(bufferConstructor->NewInstance(3, constructorArgs));
+    g_free(baton->buffer_out);
+  }
+
+  baton->callback->Call(Context::GetCurrent()->Global(), 2, argv);
   baton->callback.Dispose();
   delete baton;
   delete work;
 }
 
-Handle<Value> Resize(const Arguments& args) {
+Handle<Value> resize(const Arguments& args) {
   HandleScope scope;
   
-  ResizeBaton *baton = new ResizeBaton;
+  resize_baton *baton = new resize_baton;
-  baton->src = *String::Utf8Value(args[0]->ToString());
+  baton->file_in = *String::Utf8Value(args[0]->ToString());
-  baton->dst = *String::Utf8Value(args[1]->ToString());
+  if (args[1]->IsObject()) {
-  baton->cols = args[2]->Int32Value();
+    Local<Object> buffer = args[1]->ToObject();
-  baton->rows = args[3]->Int32Value();
+    // Take temporary copy of input buffer
-  Local<String> canvas = args[4]->ToString();
+    if (Buffer::Length(buffer) > 0) {
+      baton->buffer_in_len = Buffer::Length(buffer);
+      baton->buffer_in = g_malloc(baton->buffer_in_len);
+      memcpy(baton->buffer_in, Buffer::Data(buffer), baton->buffer_in_len);
+    }
+  }
+  baton->file_out = *String::Utf8Value(args[2]->ToString());
+  baton->width = args[3]->Int32Value();
+  baton->height = args[4]->Int32Value();
+  Local<String> canvas = args[5]->ToString();
   if (canvas->Equals(String::NewSymbol("c"))) {
-	baton->crop = true;
+    baton->crop = true;
   } else if (canvas->Equals(String::NewSymbol("w"))) {
     baton->crop = false;
-    baton->embed = 4;
+    baton->extend = VIPS_EXTEND_WHITE;
   } else if (canvas->Equals(String::NewSymbol("b"))) {
     baton->crop = false;
-    baton->embed = 0;
+    baton->extend = VIPS_EXTEND_BLACK;
-  }	
+  }
-  baton->callback = Persistent<Function>::New(Local<Function>::Cast(args[5]));
+  baton->sharpen = args[6]->BooleanValue();
+  baton->progessive = args[7]->BooleanValue();
+  baton->access_method = args[8]->BooleanValue() ? VIPS_ACCESS_SEQUENTIAL : VIPS_ACCESS_RANDOM;
+  baton->callback = Persistent<Function>::New(Local<Function>::Cast(args[9]));
 
   uv_work_t *work = new uv_work_t;
   work->data = baton;
-  uv_queue_work(uv_default_loop(), work, ResizeAsync, (uv_after_work_cb)ResizeAsyncAfter);
+  uv_queue_work(uv_default_loop(), work, resize_async, (uv_after_work_cb)resize_async_after);
-  return Undefined();
+  return scope.Close(Undefined());
+}
+
+static void at_exit(void* arg) {
+  HandleScope scope;
+  vips_shutdown();
 }
 
 extern "C" void init(Handle<Object> target) {
   HandleScope scope;
   vips_init("");
-  NODE_SET_METHOD(target, "resize", Resize);
+  AtExit(at_exit);
-};
+  NODE_SET_METHOD(target, "resize", resize);
+}
 
 NODE_MODULE(sharp, init)

tests/parallel.js

@@ -0,0 +1,29 @@
+var sharp = require("../index");
+var fs = require("fs");
+var assert = require("assert");
+var async = require("async");
+
+var inputJpg = __dirname + "/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.resize(inputJpg, sharp.buffer.jpeg, width, height, 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() {});

tests/perf.js

@@ -1,4 +1,5 @@
 var sharp = require("../index");
+var fs = require("fs");
 var imagemagick = require("imagemagick");
 var gm = require("gm");
 var epeg = require("epeg");
@@ -12,14 +13,15 @@ var outputJpg = __dirname + "/output.jpg";
 var inputPng = __dirname + "/50020484-00001.png"; // http://c.searspartsdirect.com/lis_png/PLDM/50020484-00001.png
 var outputPng = __dirname + "/output.png";
 
-var width = 640;
+var width = 720;
 var height = 480;
 
 async.series({
   jpeg: function(callback) {
+    var inputJpgBuffer = fs.readFileSync(inputJpg);
     (new Benchmark.Suite("jpeg")).add("imagemagick", {
-      "defer": true,
+      defer: true,
-      "fn": function(deferred) {
+      fn: function(deferred) {
         imagemagick.resize({
           srcPath: inputJpg,
           dstPath: outputJpg,
@@ -34,10 +36,10 @@ async.series({
           }
         });
       }
-    }).add("gm", {
+    }).add("gm-file-file", {
-      "defer": true,
+      defer: true,
-      "fn": function(deferred) {
+      fn: function(deferred) {
-        gm(inputJpg).crop(width, height).quality(80).write(outputJpg, function (err) {
+        gm(inputJpg).resize(width, height).quality(80).write(outputJpg, function (err) {
           if (err) {
             throw err;
           } else {
@@ -45,17 +47,37 @@ async.series({
           }
         });
       }
-    }).add("epeg", {
+    }).add("gm-file-buffer", {
-      "defer": true,
+      defer: true,
-      "fn": function(deferred) {
+      fn: function(deferred) {
+        gm(inputJpg).resize(width, height).quality(80).toBuffer(function (err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("epeg-file-file", {
+      defer: true,
+      fn: function(deferred) {
         var image = new epeg.Image({path: inputJpg});
         image.downsize(width, height, 80).saveTo(outputJpg);
         deferred.resolve();
       }
-    }).add("sharp", {
+    }).add("epeg-file-buffer", {
-      "defer": true,
+      defer: true,
-      "fn": function(deferred) {
+      fn: function(deferred) {
-        sharp.crop(inputJpg, outputJpg, width, height, function(err) {
+        var image = new epeg.Image({path: inputJpg});
+        var buffer = image.downsize(width, height, 80).process();
+        assert.notStrictEqual(null, buffer);
+        deferred.resolve();
+      }
+    }).add("sharp-buffer-file", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.resize(inputJpgBuffer, outputJpg, width, height, function(err) {
           if (err) {
             throw err;
           } else {
@@ -63,6 +85,77 @@ async.series({
           }
         });
       }
+    }).add("sharp-buffer-buffer", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.resize(inputJpgBuffer, sharp.buffer.jpeg, width, height, function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp-file-file", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.resize(inputJpg, outputJpg, width, height, function(err) {
+          if (err) {
+            throw err;
+          } else {
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp-file-buffer", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.resize(inputJpg, sharp.buffer.jpeg, width, height, function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp-file-buffer-sharpen", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.resize(inputJpg, sharp.buffer.jpeg, width, height, {sharpen: true}, function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp-file-buffer-progressive", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.resize(inputJpg, sharp.buffer.jpeg, width, height, {progressive: true}, function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp-file-buffer-sequentialRead", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.resize(inputJpg, sharp.buffer.jpeg, width, height, {sequentialRead: true}, function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            deferred.resolve();
+          }
+        });
+      }
     }).on("cycle", function(event) {
       console.log("jpeg " + String(event.target));
     }).on("complete", function() {
@@ -70,9 +163,10 @@ async.series({
     }).run();
   },
   png: function(callback) {
+    var inputPngBuffer = fs.readFileSync(inputPng);
     (new Benchmark.Suite("png")).add("imagemagick", {
-      "defer": true,
+      defer: true,
-      "fn": function(deferred) {
+      fn: function(deferred) {
         imagemagick.resize({
           srcPath: inputPng,
           dstPath: outputPng,
@@ -86,10 +180,10 @@ async.series({
           }
         });
       }
-    }).add("gm", {
+    }).add("gm-file-file", {
-      "defer": true,
+      defer: true,
-      "fn": function(deferred) {
+      fn: function(deferred) {
-        gm(inputPng).crop(width, height).write(outputPng, function (err) {
+        gm(inputPng).resize(width, height).write(outputPng, function (err) {
           if (err) {
             throw err;
           } else {
@@ -97,13 +191,96 @@ async.series({
           }
         });
       }
-    }).add("sharp", {
+    }).add("gm-file-buffer", {
-      "defer": true,
+      defer: true,
-      "fn": function(deferred) {
+      fn: function(deferred) {
-        sharp.crop(inputPng, outputPng, width, height, function(err) {
+        gm(inputPng).resize(width, height).quality(80).toBuffer(function (err, buffer) {
           if (err) {
             throw err;
           } else {
+            assert.notStrictEqual(null, buffer);
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp-buffer-file", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.resize(inputPngBuffer, outputPng, width, height, function(err) {
+          if (err) {
+            throw err;
+          } else {
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp-buffer-buffer", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.resize(inputPngBuffer, sharp.buffer.png, width, height, function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp-file-file", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.resize(inputPng, outputPng, width, height, function(err) {
+          if (err) {
+            throw err;
+          } else {
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp-file-buffer", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.resize(inputPng, sharp.buffer.png, width, height, function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp-file-buffer-sharpen", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.resize(inputPng, sharp.buffer.png, width, height, {sharpen: true}, function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp-file-buffer-progressive", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.resize(inputPng, sharp.buffer.png, width, height, {progressive: true}, function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp-file-buffer-sequentialRead", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.resize(inputPng, sharp.buffer.png, width, height, {sequentialRead: true}, function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
             deferred.resolve();
           }
         });
@@ -115,7 +292,8 @@ async.series({
     }).run();
   }
 }, function(err, results) {
-  results.forEach(function(format, fastest) {
+  assert(!err, err);
-    assert(fastest === "sharp", "sharp was slower than " + fastest + " for " + format);
+  Object.keys(results).forEach(function(format) {
+    assert.strictEqual("sharp", results[format].toString().substr(0, 5), "sharp was slower than " + results[format] + " for " + format);
   });
 });