Add support for PNG format. Close #2.

.gitignore

@@ -13,5 +13,6 @@ results
 build
 node_modules
 tests/output.jpg
+tests/output.png
 
 npm-debug.log

.travis.yml

@@ -1,8 +0,0 @@
-language: node_js
-node_js:
-  - "0.11"
-  - "0.10"
-before_install:
- - sudo apt-get update -qq
- - sudo apt-get install -qq libvips-dev imagemagick
- - sudo ln -s /usr/lib/pkgconfig/vips-7.26.pc /usr/lib/pkgconfig/vips.pc

README.md

@@ -7,9 +7,9 @@ _adj_
 3. shrewd or astute: a sharp bargainer. 
 4. (Informal.) very stylish: a sharp dresser; a sharp jacket. 
 
-The typical use case for this high speed Node.js module is to convert a large JPEG image to smaller JPEG images of varying dimensions.
+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 images, always obeys the requested dimensions by either cropping or embedding and insists on a mild sharpen of the resulting image.
+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.
 
 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.
 
@@ -19,7 +19,7 @@ Performance is 4x-8x faster than ImageMagick and 2x-4x faster than GraphicsMagic
 
 * Node.js v0.8+
 * node-gyp
-* libvips-dev 7.28+
+* libvips-dev 7.28+ (7.36+ for optimal JPEG Huffman coding)
 
 ```
 sudo npm install -g node-gyp
@@ -40,7 +40,7 @@ When installed as a package, please symlink `vips-7.28.pc` (or later, installed
 
 ### crop(inputPath, outputPath, width, height, callback)
 
-Scale and crop JPEG `inputPath` to `width` x `height` and write JPEG to `outputPath` calling `callback` when complete.
+Scale and crop `inputPath` to `width` x `height` and write to `outputPath` calling `callback` when complete.
 
 Example:
 
@@ -56,29 +56,29 @@ sharp.crop("input.jpg", "output.jpg", 300, 200, function(err) {
 
 ### embedWhite(inputPath, outputPath, width, height, callback)
 
-Scale and embed JPEG `inputPath` to `width` x `height` using a white canvas and write JPEG to `outputPath` calling `callback` when complete.
+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.jpg", 200, 300, function(err) {
+sharp.embedWhite("input.jpg", "output.png", 200, 300, function(err) {
   if (err) {
     throw err;
   }
   // output.jpg is a 200 pixels wide and 300 pixels high image
-  // containing a scaled version of input.jpg embedded on a white canvas
+  // containing a scaled version of input.png embedded on a white canvas
 });
 ```
 
 ### embedBlack(inputPath, outputPath, width, height, callback)
 
-Scale and embed JPEG `inputPath` to `width` x `height` using a black canvas and write JPEG to `outputPath` calling `callback` when complete.
+Scale and embed `inputPath` to `width` x `height` using a black canvas and write to `outputPath` calling `callback` when complete.
 
 ```javascript
-sharp.embedBlack("input.jpg", "output.jpg", 200, 300, function(err) {
+sharp.embedBlack("input.png", "output.png", 200, 300, function(err) {
   if (err) {
     throw err;
   }
-  // output.jpg is a 200 pixels wide and 300 pixels high image
-  // containing a scaled version of input.jpg embedded on a black canvas
+  // output.png is a 200 pixels wide and 300 pixels high image
+  // containing a scaled version of input.png embedded on a black canvas
 });
 ```
 
@@ -89,29 +89,37 @@ sharp.embedBlack("input.jpg", "output.jpg", 200, 300, function(err) {
 
 ## Performance
 
-### AMD Athlon 4x core 3.3GHz 512KB L2
+Test environment:
 
-* imagemagick x 5.55 ops/sec ±0.45% (31 runs sampled)
-* gm x 10.31 ops/sec ±3.57% (53 runs sampled)
-* epeg x 27.79 ops/sec ±0.12% (69 runs sampled)
-* sharp x 31.52 ops/sec ±8.74% (80 runs sampled)
+* AMD Athlon 4 core 3.3GHz 512KB L2 CPU 1333 DDR3
+* libvips 7.36
+* libjpeg-turbo8 1.2.1
+* libpng 1.6.6
+* zlib1g 1.2.7
 
-### AWS t1.micro
+#### JPEG
 
-* imagemagick x 1.36 ops/sec ±0.96% (11 runs sampled)
-* sharp x 12.42 ops/sec ±5.84% (64 runs sampled)
+* imagemagick x 5.53 ops/sec ±0.55% (31 runs sampled)
+* 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)
 
-### AWS m1.medium
+#### PNG
 
-* imagemagick x 1.38 ops/sec ±0.45% (11 runs sampled)
-* sharp x 12.66 ops/sec ±5.54% (65 runs sampled)
+* imagemagick x 4.65 ops/sec ±0.37% (27 runs sampled)
+* gm x 21.65 ops/sec ±0.18% (56 runs sampled)
+* sharp x 39.47 ops/sec ±6.78% (68 runs sampled)
 
-### AWS c1.medium
+## Licence
 
-* imagemagick x 2.10 ops/sec ±0.67% (15 runs sampled)
-* sharp x 18.97 ops/sec ±10.54% (52 runs sampled)
+Copyright 2013 Lovell Fuller
 
-### AWS m3.xlarge
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at [http://www.apache.org/licenses/LICENSE-2.0](http://www.apache.org/licenses/LICENSE-2.0.html)
 
-* imagemagick x 4.46 ops/sec ±0.33% (26 runs sampled)
-* sharp x 28.89 ops/sec ±7.75% (74 runs sampled)
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

index.js

@@ -1,13 +1,13 @@
 var sharp = require("./build/Release/sharp");
 
 module.exports.crop = function(input, output, width, height, callback) {
-  sharp.resize(input, output, width, height, "c", callback)
-}
+  sharp.resize(input, output, width, height, "c", callback);
+};
 
 module.exports.embedWhite = function(input, output, width, height, callback) {
-  sharp.resize(input, output, width, height, "w", callback)
-}
+  sharp.resize(input, output, width, height, "w", callback);
+};
 
 module.exports.embedBlack = function(input, output, width, height, callback) {
-  sharp.resize(input, output, width, height, "b", callback)
-}
+  sharp.resize(input, output, width, height, "b", callback);
+};

package.json

@@ -1,26 +1,19 @@
 {
   "name": "sharp",
-  "version": "0.0.4",
+  "version": "0.0.5",
+  "author": "Lovell Fuller",
+  "description": "High performance module to resize JPEG and PNG images using the libvips image processing library",
+  "scripts": {
+    "test": "node tests/perf.js"
+  },
   "main": "index.js",
-  "description": "High performance Node.js module to resize JPEG images using the libvips image processing library",
   "repository": {
     "type": "git",
     "url": "git://github.com/lovell/sharp"
   },
-  "devDependencies": {
-    "imagemagick": "*",
-    "gm": "*",
-    "epeg": "*",
-    "benchmark": "*"
-  },
-  "scripts": {
-    "test": "node tests/perf.js"
-  },
-  "engines": {
-    "node": ">=0.8"
-  },
   "keywords": [
     "jpeg",
+    "png",
     "resize",
     "thumbnail",
     "sharpen",
@@ -29,6 +22,15 @@
     "libvips",
     "fast"
   ],
-  "author": "Lovell Fuller",
-  "license": "Apache 2.0"
+  "devDependencies": {
+    "imagemagick": "*",
+    "gm": "*",
+    "epeg": "*",
+    "async": "*",
+    "benchmark": "*"
+  },
+  "license": "Apache 2.0",
+  "engines": {
+    "node": ">=0.8"
+  }
 }

src/sharp.cc

@@ -35,11 +35,22 @@ struct ResizeBaton {
   Persistent<Function> callback;
 };
 
+bool EndsWith(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) {
   ResizeBaton* baton = static_cast<ResizeBaton*>(work->data);
 
   VipsImage *in = vips_image_new_mode((baton->src).c_str(), "p");
-  vips_jpegload((baton->src).c_str(), &in, NULL);
+  if (EndsWith(baton->src, ".jpg") || EndsWith(baton->src, ".jpeg"))  {
+    vips_jpegload((baton->src).c_str(), &in, NULL);
+  } else if (EndsWith(baton->src, ".png")) {
+    vips_pngload((baton->src).c_str(), &in, NULL);
+  } else {
+    (baton->err).append("Unsupported input file type");
+    return;
+  }
   if (in == NULL) {
     (baton->err).append(vips_error_buffer());
     vips_error_clear();
@@ -114,9 +125,18 @@ void ResizeAsync(uv_work_t *work) {
   }
   img = t[3];
 
-  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();
+  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");
   }
 }
 

tests/perf.js

@@ -2,63 +2,120 @@ var sharp = require("../index");
 var imagemagick = require("imagemagick");
 var gm = require("gm");
 var epeg = require("epeg");
+var async = require("async");
 var assert = require("assert");
 var Benchmark = require("benchmark");
 
-var input = __dirname + "/2569067123_aca715a2ee_o.jpg"; // http://www.flickr.com/photos/grizdave/2569067123/
-var output = __dirname + "/output.jpg";
+var inputJpg = __dirname + "/2569067123_aca715a2ee_o.jpg"; // http://www.flickr.com/photos/grizdave/2569067123/
+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 height = 480;
 
-var suite = new Benchmark.Suite;
-suite.add("imagemagick", {
-  "defer": true,
-  "fn": function(deferred) {
-    imagemagick.resize({
-      srcPath: input,
-      dstPath: output,
-      quality: 0.75,
-      width: width,
-      height: height
-    }, function(err) {
-      if (err) {
-        throw err;
-      } else {
+async.series({
+  jpeg: function(callback) {
+    (new Benchmark.Suite("jpeg")).add("imagemagick", {
+      "defer": true,
+      "fn": function(deferred) {
+        imagemagick.resize({
+          srcPath: inputJpg,
+          dstPath: outputJpg,
+          quality: 0.8,
+          width: width,
+          height: height
+        }, function(err) {
+          if (err) {
+            throw err;
+          } else {
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("gm", {
+      "defer": true,
+      "fn": function(deferred) {
+        gm(inputJpg).crop(width, height).quality(80).write(outputJpg, function (err) {
+          if (err) {
+            throw err;
+          } else {
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("epeg", {
+      "defer": true,
+      "fn": function(deferred) {
+        var image = new epeg.Image({path: inputJpg});
+        image.downsize(width, height, 80).saveTo(outputJpg);
         deferred.resolve();
       }
-    });
-  }
-}).add("gm", {
-  "defer": true,
-  "fn": function(deferred) {
-    gm(input).crop(width, height).write(output, function (err) {
-      if (err) {
-        throw err;
-      } else {
-        deferred.resolve();
+    }).add("sharp", {
+      "defer": true,
+      "fn": function(deferred) {
+        sharp.crop(inputJpg, outputJpg, width, height, function(err) {
+          if (err) {
+            throw err;
+          } else {
+            deferred.resolve();
+          }
+        });
       }
-    });
-  }
-}).add("epeg", {
-  "defer": true,
-  "fn": function(deferred) {
-    var image = new epeg.Image({path: input});
-    image.downsize(width, height).saveTo(output);
-    deferred.resolve();
-  }
-}).add("sharp", {
-  "defer": true,
-  "fn": function(deferred) {
-    sharp.crop(input, output, width, height, function(err) {
-      if (err) {
-        throw err;
-      } else {
-        deferred.resolve();
+    }).on("cycle", function(event) {
+      console.log("jpeg " + String(event.target));
+    }).on("complete", function() {
+      callback(null, this.filter("fastest").pluck("name"));
+    }).run();
+  },
+  png: function(callback) {
+    (new Benchmark.Suite("png")).add("imagemagick", {
+      "defer": true,
+      "fn": function(deferred) {
+        imagemagick.resize({
+          srcPath: inputPng,
+          dstPath: outputPng,
+          width: width,
+          height: height
+        }, function(err) {
+          if (err) {
+            throw err;
+          } else {
+            deferred.resolve();
+          }
+        });
       }
-    });
+    }).add("gm", {
+      "defer": true,
+      "fn": function(deferred) {
+        gm(inputPng).crop(width, height).write(outputPng, function (err) {
+          if (err) {
+            throw err;
+          } else {
+            deferred.resolve();
+          }
+        });
+      }
+    }).add("sharp", {
+      "defer": true,
+      "fn": function(deferred) {
+        sharp.crop(inputPng, outputPng, width, height, function(err) {
+          if (err) {
+            throw err;
+          } else {
+            deferred.resolve();
+          }
+        });
+      }
+    }).on("cycle", function(event) {
+      console.log(" png " + String(event.target));
+    }).on("complete", function() {
+      callback(null, this.filter("fastest").pluck("name"));
+    }).run();
   }
-}).on("cycle", function(event) {
-  console.log(String(event.target));
-}).on("complete", function() {
-  assert(this.filter("fastest").pluck("name") == "sharp");
-}).run();
+}, function(err, results) {
+  results.forEach(function(format, fastest) {
+    assert(fastest === "sharp", "sharp was slower than " + fastest + " for " + format);
+  });
+});