Allow SIMD vector unit to be toggled on/off #172

Currently defaults to off but future versions may default to on

docs/api.md

@@ -426,8 +426,6 @@ Use WebP format for the output image.
 
 #### raw()
 
-_Requires libvips 7.42.0+_
-
 Provide raw, uncompressed uint8 (unsigned char) image data for Buffer and Stream based output.
 
 The number of channels depends on the input image and selected options.
@@ -497,13 +495,11 @@ An advanced setting for the _zlib_ compression level of the lossless PNG output
 
 #### withoutAdaptiveFiltering()
 
-_Requires libvips 7.42.0+_
-
 An advanced setting to disable adaptive row filtering for the lossless PNG output format.
 
 #### trellisQuantisation() / trellisQuantization()
 
-_Requires libvips 8.0.0+ compiled against mozjpeg 3.0+_
+_Requires libvips to have been compiled with mozjpeg support_
 
 An advanced setting to apply the use of
 [trellis quantisation](http://en.wikipedia.org/wiki/Trellis_quantization) with JPEG output.
@@ -511,7 +507,7 @@ Reduces file size and slightly increases relative quality at the cost of increas
 
 #### overshootDeringing()
 
-_Requires libvips 8.0.0+ compiled against mozjpeg 3.0+_
+_Requires libvips to have been compiled with mozjpeg support_
 
 An advanced setting to reduce the effects of
 [ringing](http://en.wikipedia.org/wiki/Ringing_%28signal%29) in JPEG output,
@@ -519,7 +515,7 @@ in particular where black text appears on a white background (or vice versa).
 
 #### optimiseScans() / optimizeScans()
 
-_Requires libvips 8.0.0+ compiled against mozjpeg 3.0+_
+_Requires libvips to have been compiled with mozjpeg support_
 
 An advanced setting for progressive (interlace) JPEG output.
 Calculates which spectrum of DCT coefficients uses the fewest bits.
@@ -633,3 +629,31 @@ Provides access to internal task counters.
 ```javascript
 var counters = sharp.counters(); // { queue: 2, process: 4 }
 ```
+
+#### sharp.simd([enable])
+
+_Requires libvips to have been compiled with liborc support_
+
+Improves the performance of `resize`, `blur` and `sharpen` operations
+by taking advantage of the SIMD vector unit of the CPU.
+
+* `enable`, if present, is a boolean where `true` enables and `false` disables the use of SIMD.
+
+This method always returns the current state.
+
+This feature is currently disabled by default
+but future versions may enable it by default.
+
+When enabled, versions of liborc prior to 0.4.24
+and versions of libvips prior to 8.2.0
+have been known to crash under heavy load.
+
+```javascript
+var simd = sharp.simd();
+// simd is `true` is SIMD is currently enabled
+```
+
+```javascript
+var simd = sharp.simd(true);
+// attempts to enable the use of SIMD, returning true if available
+```

docs/changelog.md

@@ -2,7 +2,12 @@
 
 ### v0.12 - "*look*"
 
-#### v0.12.1 - TBD
+#### v0.12.1 - 12<sup>th</sup> December 2015
+
+* Allow use of SIMD vector instructions (via liborc) to be toggled on/off.
+  [#172](https://github.com/lovell/sharp/issues/172)
+  [@bkw](https://github.com/bkw)
+  [@puzrin](https://github.com/puzrin)
 
 * Ensure embedded ICC profiles output with perceptual intent.
   [#321](https://github.com/lovell/sharp/issues/321)

index.js

@@ -863,3 +863,15 @@ module.exports.concurrency = function(concurrency) {
 module.exports.counters = function() {
   return sharp.counters();
 };
+
+/*
+  Get and set use of SIMD vector unit instructions
+*/
+module.exports.simd = function(simd) {
+  if (typeof simd !== 'boolean') {
+    simd = null;
+  }
+  return sharp.simd(simd);
+};
+// Switch off default
+module.exports.simd(false);

package.json

@@ -56,7 +56,7 @@
   },
   "devDependencies": {
     "async": "^1.5.0",
-    "coveralls": "^2.11.4",
+    "coveralls": "^2.11.6",
     "exif-reader": "^1.0.0",
     "icc": "^0.0.2",
     "istanbul": "^0.4.0",

src/sharp.cc

@@ -26,6 +26,8 @@ NAN_MODULE_INIT(init) {
     Nan::GetFunction(Nan::New<v8::FunctionTemplate>(concurrency)).ToLocalChecked());
   Nan::Set(target, Nan::New("counters").ToLocalChecked(),
     Nan::GetFunction(Nan::New<v8::FunctionTemplate>(counters)).ToLocalChecked());
+  Nan::Set(target, Nan::New("simd").ToLocalChecked(),
+    Nan::GetFunction(Nan::New<v8::FunctionTemplate>(simd)).ToLocalChecked());
   Nan::Set(target, Nan::New("libvipsVersion").ToLocalChecked(),
     Nan::GetFunction(Nan::New<v8::FunctionTemplate>(libvipsVersion)).ToLocalChecked());
   Nan::Set(target, Nan::New("format").ToLocalChecked(),

src/utilities.cc

@@ -1,6 +1,7 @@
 #include <cmath>
 #include <node.h>
 #include <vips/vips.h>
+#include <vips/vector.h>
 
 #include "nan.h"
 
@@ -81,6 +82,20 @@ NAN_METHOD(counters) {
   info.GetReturnValue().Set(counters);
 }
 
+/*
+  Get and set use of SIMD vector unit instructions
+*/
+NAN_METHOD(simd) {
+  HandleScope();
+
+  // Set state
+  if (info[0]->IsBoolean()) {
+    vips_vector_set_enabled(To<bool>(info[0]).FromJust());
+  }
+  // Get state
+  info.GetReturnValue().Set(New<Boolean>(vips_vector_isenabled()));
+}
+
 /*
   Get libvips version
 */

src/utilities.h

@@ -6,6 +6,7 @@
 NAN_METHOD(cache);
 NAN_METHOD(concurrency);
 NAN_METHOD(counters);
+NAN_METHOD(simd);
 NAN_METHOD(libvipsVersion);
 NAN_METHOD(format);
 NAN_METHOD(_maxColourDistance);

test/bench/package.json

@@ -13,7 +13,7 @@
     "gm": "^1.21.0",
     "imagemagick": "^0.1.3",
     "imagemagick-native": "elad/node-imagemagick-native",
-    "jimp": "^0.2.19",
+    "jimp": "^0.2.20",
     "lwip": "^0.0.8",
     "semver": "^5.1.0"
   },

test/bench/parallel.js

@@ -12,6 +12,7 @@ var width = 720;
 var height = 480;
 
 sharp.concurrency(1);
+sharp.simd(true);
 
 var timer = setInterval(function() {
   console.dir(sharp.counters());

test/bench/perf.js

@@ -35,6 +35,8 @@ var magickFilterBicubic = 'Lanczos';
 
 // Disable libvips cache to ensure tests are as fair as they can be
 sharp.cache(0);
+// Enable use of SIMD
+sharp.simd(true);
 
 async.series({
   'jpeg-linear': function(callback) {
@@ -496,6 +498,24 @@ async.series({
             }
           });
       }
+    }).add('sharp-without-simd', {
+      defer: true,
+      fn: function(deferred) {
+        sharp.simd(false);
+        sharp(inputJpgBuffer)
+          .rotate(90)
+          .interpolateWith(sharp.interpolator.bilinear)
+          .resize(width, height)
+          .toBuffer(function(err, buffer) {
+            sharp.simd(true);
+            if (err) {
+              throw err;
+            } else {
+              assert.notStrictEqual(null, buffer);
+              deferred.resolve();
+            }
+          });
+      }
     }).add('sharp-sequentialRead', {
       defer: true,
       fn: function(deferred) {

test/bench/random.js

@@ -8,6 +8,8 @@ var Benchmark = require('benchmark');
 var sharp = require('../../index');
 var fixtures = require('../fixtures');
 
+sharp.simd(true);
+
 var min = 320;
 var max = 960;
 

test/unit/util.js

@@ -51,6 +51,21 @@ describe('Utilities', function() {
     });
   });
 
+  describe('SIMD', function() {
+    it('Can get current state', function() {
+      var simd = sharp.simd();
+      assert.strictEqual(typeof simd, 'boolean');
+    });
+    it('Can disable', function() {
+      var simd = sharp.simd(false);
+      assert.strictEqual(simd, false);
+    });
+    it('Can attempt to enable', function() {
+      var simd = sharp.simd(true);
+      assert.strictEqual(typeof simd, 'boolean');
+    });
+  });
+
   describe('Format', function() {
     it('Contains expected attributes', function() {
       assert.strictEqual('object', typeof sharp.format);