Add support for writing image data output to a buffer, boosting ops/sec by ~7%. Partially implements #3.

README.md

@@ -33,11 +33,9 @@ If you prefer to run a stable, package-managed environment such as Ubuntu 12.04
 
 	var sharp = require("sharp");
 
-### crop(inputPath, outputPath, width, height, callback)
+### crop(input, output, width, height, 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:
 
 ```javascript
 sharp.crop("input.jpg", "output.jpg", 300, 200, function(err) {
@@ -49,12 +47,30 @@ sharp.crop("input.jpg", "output.jpg", 300, 200, function(err) {
 });
 ```
 
-### embedWhite(inputPath, outputPath, width, height, callback)
+```javascript
-
+sharp.crop("input.jpg", sharp.buffer.jpeg, 300, 200, function(err, buffer) {
-Scale and embed `inputPath` to `width` x `height` using a white canvas and write to `outputPath` calling `callback` when complete.
+  if (err) {
+    throw err;
+  }
+  // buffer contains JPEG image data
+});
+```
 
 ```javascript
-sharp.embedWhite("input.jpg", "output.png", 200, 300, function(err) {
+sharp.crop("input.jpg", sharp.buffer.png, 300, 200, function(err, buffer) {
+  if (err) {
+    throw err;
+  }
+  // buffer contains PNG image data (converted from JPEG)
+});
+```
+
+### embedWhite(input, output, width, height, callback)
+
+Scale and embed to `width` x `height` using a white canvas calling `callback` when complete.
+
+```javascript
+sharp.embedWhite("input.jpg", "output.jpg", 200, 300, function(err) {
   if (err) {
     throw err;
   }
@@ -63,9 +79,18 @@ sharp.embedWhite("input.jpg", "output.png", 200, 300, function(err) {
 });
 ```
 
-### embedBlack(inputPath, outputPath, width, height, callback)
+```javascript
+sharp.embedWhite("input.jpg", sharp.buffer.jpeg, 200, 300, function(err, buffer) {
+  if (err) {
+    throw err;
+  }
+  // buffer contains JPEG image data
+});
+```
 
-Scale and embed `inputPath` to `width` x `height` using a black canvas and write to `outputPath` calling `callback` when complete.
+### embedBlack(input, output, width, height, callback)
+
+Scale and embed to `width` x `height` using a black canvas calling `callback` when complete.
 
 ```javascript
 sharp.embedBlack("input.png", "output.png", 200, 300, function(err) {
@@ -77,6 +102,19 @@ sharp.embedBlack("input.png", "output.png", 200, 300, function(err) {
 });
 ```
 
+### Parameters common to all methods
+
+#### input
+
+String containing the filename to read from.
+
+#### output
+
+One of:
+* String containing the filename to write to.
+* `sharp.buffer.jpeg` to pass a Buffer containing JPEG image data to `callback`.
+* `sharp.buffer.png` to pass a Buffer containing PNG image data to `callback`.
+
 ## Testing
 
 	npm test
@@ -86,8 +124,8 @@ 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
 
@@ -96,17 +134,19 @@ Test environment:
 * 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)
+* sharp-file x 31.60 ops/sec ±8.80% (80 runs sampled)
+* sharp-buffer x 34.04 ops/sec ±0.36% (82 runs sampled)
 
 #### PNG
 
 * 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)
+* sharp-file x 39.47 ops/sec ±6.78% (68 runs sampled)
+* sharp-buffer x 42.87 ops/sec ±0.19% (71 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.

index.js

@@ -1,5 +1,10 @@
 var sharp = require("./build/Release/sharp");
 
+module.exports.buffer = {
+  jpeg: "__jpeg",
+  png: "__png"
+};
+
 module.exports.crop = function(input, output, width, height, callback) {
   sharp.resize(input, output, width, height, "c", callback);
 };

package.json

@@ -1,6 +1,6 @@
 {
   "name": "sharp",
-  "version": "0.0.6",
+  "version": "0.0.7",
   "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

@@ -3,8 +3,10 @@
 #include <string>
 #include <vector>
 #include <vips/vips.h>
+#include <node_buffer.h>
 
 using namespace v8;
+using namespace node;
 
 // Free VipsImage children when object goes out of scope
 // Thanks due to https://github.com/dosx/node-vips
@@ -27,12 +29,16 @@ class ImageFreer {
 struct ResizeBaton {
   std::string src;
   std::string dst;
+  void* buffer_out;
+  size_t buffer_out_len;
   int  cols;
   int  rows;
   bool crop;
   int  embed;
   std::string err;
   Persistent<Function> callback;
+
+  ResizeBaton() : buffer_out_len(0) {}
 };
 
 bool EndsWith(std::string const &str, std::string const &end) {
@@ -125,12 +131,28 @@ void ResizeAsync(uv_work_t *work) {
   }
   img = t[3];
 
-  if (EndsWith(baton->dst, ".jpg") || EndsWith(baton->dst, ".jpeg"))  {
+  if (baton->dst == "__jpeg") {
+    // Write JPEG to buffer
+    if (vips_jpegsave_buffer(img, &baton->buffer_out, &baton->buffer_out_len, "strip", TRUE, "Q", 80, "optimize_coding", TRUE, NULL)) {
+      (baton->err).append(vips_error_buffer());
+      vips_error_clear();
+      return;
+    }
+  } else if (baton->dst == "__png") {
+    // Write PNG to buffer
+    if (vips_pngsave_buffer(img, &baton->buffer_out, &baton->buffer_out_len, "strip", TRUE, "compression", 6, "interlace", FALSE, NULL)) {
+      (baton->err).append(vips_error_buffer());
+      vips_error_clear();
+      return;
+    }
+  } else if (EndsWith(baton->dst, ".jpg") || EndsWith(baton->dst, ".jpeg"))  {
+    // Write JPEG to file
     if (vips_foreign_save(img, baton->dst.c_str(), "strip", TRUE, "Q", 80, "optimize_coding", TRUE, NULL)) {
       (baton->err).append(vips_error_buffer());
       vips_error_clear();
     }
   } else if (EndsWith(baton->dst, ".png")) {
+    // Write PNG to file
     if (vips_foreign_save(img, baton->dst.c_str(), "strip", TRUE, "compression", 6, "interlace", FALSE, NULL)) {
       (baton->err).append(vips_error_buffer());
       vips_error_clear();
@@ -145,14 +167,18 @@ void ResizeAsyncAfter(uv_work_t *work, int status) {
 
   ResizeBaton *baton = static_cast<ResizeBaton*>(work->data);
 
-  Local<Value> argv[1];
+  Local<Value> null = Local<Value>::New(Null());
+  Local<Value> argv[2] = {null, null};
   if (!baton->err.empty()) {
+    // Error
     argv[0] = String::New(baton->err.data(), baton->err.size());
-  } else {
+  } else if (baton->buffer_out_len > 0) {
-    argv[0] = Local<Value>::New(Null());
+    // Buffer
+    Buffer *buffer = Buffer::New((const char*)(baton->buffer_out), baton->buffer_out_len);
+    argv[1] = Local<Object>::New(buffer->handle_);
   }
 
-  baton->callback->Call(Context::GetCurrent()->Global(), 1, argv);
+  baton->callback->Call(Context::GetCurrent()->Global(), 2, argv);
   baton->callback.Dispose();
   delete baton;
   delete work;
@@ -168,7 +194,7 @@ Handle<Value> Resize(const Arguments& args) {
   baton->rows = args[3]->Int32Value();
   Local<String> canvas = args[4]->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;
@@ -190,4 +216,4 @@ extern "C" void init(Handle<Object> target) {
   NODE_SET_METHOD(target, "resize", Resize);
 };
 
-NODE_MODULE(sharp, init)
+NODE_MODULE(sharp, init);

tests/perf.js

@@ -8,9 +8,11 @@ var Benchmark = require("benchmark");
 
 var inputJpg = __dirname + "/2569067123_aca715a2ee_o.jpg"; // http://www.flickr.com/photos/grizdave/2569067123/
 var outputJpg = __dirname + "/output.jpg";
+var outputJpgLength = 47035;
 
 var inputPng = __dirname + "/50020484-00001.png"; // http://c.searspartsdirect.com/lis_png/PLDM/50020484-00001.png
 var outputPng = __dirname + "/output.png";
+var outputPngLength = 60379;
 
 var width = 640;
 var height = 480;
@@ -18,8 +20,8 @@ var height = 480;
 async.series({
   jpeg: function(callback) {
     (new Benchmark.Suite("jpeg")).add("imagemagick", {
-      "defer": true,
+      defer: true,
-      "fn": function(deferred) {
+      fn: function(deferred) {
         imagemagick.resize({
           srcPath: inputJpg,
           dstPath: outputJpg,
@@ -35,8 +37,8 @@ async.series({
         });
       }
     }).add("gm", {
-      "defer": true,
+      defer: true,
-      "fn": function(deferred) {
+      fn: function(deferred) {
         gm(inputJpg).crop(width, height).quality(80).write(outputJpg, function (err) {
           if (err) {
             throw err;
@@ -46,15 +48,15 @@ async.series({
         });
       }
     }).add("epeg", {
-      "defer": true,
+      defer: true,
-      "fn": function(deferred) {
+      fn: function(deferred) {
         var image = new epeg.Image({path: inputJpg});
         image.downsize(width, height, 80).saveTo(outputJpg);
         deferred.resolve();
       }
-    }).add("sharp", {
+    }).add("sharp-file", {
-      "defer": true,
+      defer: true,
-      "fn": function(deferred) {
+      fn: function(deferred) {
         sharp.crop(inputJpg, outputJpg, width, height, function(err) {
           if (err) {
             throw err;
@@ -63,6 +65,19 @@ async.series({
           }
         });
       }
+    }).add("sharp-buffer", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.crop(inputJpg, sharp.buffer.jpeg, width, height, function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            assert.strictEqual(outputJpgLength, buffer.length);
+            deferred.resolve();
+          }
+        });
+      }
     }).on("cycle", function(event) {
       console.log("jpeg " + String(event.target));
     }).on("complete", function() {
@@ -71,8 +86,8 @@ async.series({
   },
   png: function(callback) {
     (new Benchmark.Suite("png")).add("imagemagick", {
-      "defer": true,
+      defer: true,
-      "fn": function(deferred) {
+      fn: function(deferred) {
         imagemagick.resize({
           srcPath: inputPng,
           dstPath: outputPng,
@@ -87,8 +102,8 @@ async.series({
         });
       }
     }).add("gm", {
-      "defer": true,
+      defer: true,
-      "fn": function(deferred) {
+      fn: function(deferred) {
         gm(inputPng).crop(width, height).write(outputPng, function (err) {
           if (err) {
             throw err;
@@ -97,9 +112,9 @@ async.series({
           }
         });
       }
-    }).add("sharp", {
+    }).add("sharp-file", {
-      "defer": true,
+      defer: true,
-      "fn": function(deferred) {
+      fn: function(deferred) {
         sharp.crop(inputPng, outputPng, width, height, function(err) {
           if (err) {
             throw err;
@@ -108,6 +123,19 @@ async.series({
           }
         });
       }
+    }).add("sharp-buffer", {
+      defer: true,
+      fn: function(deferred) {
+        sharp.crop(inputPng, sharp.buffer.png, width, height, function(err, buffer) {
+          if (err) {
+            throw err;
+          } else {
+            assert.notStrictEqual(null, buffer);
+            assert.strictEqual(outputPngLength, buffer.length);
+            deferred.resolve();
+          }
+        });
+      }
     }).on("cycle", function(event) {
       console.log(" png " + String(event.target));
     }).on("complete", function() {
@@ -117,6 +145,6 @@ async.series({
 }, function(err, results) {
   assert(!err, err);
   Object.keys(results).forEach(function(format) {
-    assert(results[format] == "sharp", "sharp was slower than " + results[format] + " for " + format);
+    assert.strictEqual("sharp", results[format].toString().substr(0, 5), "sharp was slower than " + results[format] + " for " + format);
   });
 });