js2/mwEmbed/libClipEdit/pixastic-lib/actions/sepia.js

   1 /*
   2  * Pixastic Lib - Sepia filter - v0.1.0
   3  * Copyright (c) 2008 Jacob Seidelin, jseidelin@nihilogic.dk, http://blog.nihilogic.dk/
   4  * MIT License [http://www.opensource.org/licenses/mit-license.php]
   5  */
   6
   7 Pixastic.Actions.sepia = {
   8
   9         process : function(params) {
  10                 var mode = (parseInt(params.options.mode,10)||0);
  11                 if (mode < 0) mode = 0;
  12                 if (mode > 1) mode = 1;
  13
  14                 if (Pixastic.Client.hasCanvasImageData()) {
  15                         var data = Pixastic.prepareData(params);
  16                         var rect = params.options.rect;
  17                         var w = rect.width;
  18                         var h = rect.height;
  19                         var w4 = w*4;
  20                         var y = h;
  21                         do {
  22                                 var offsetY = (y-1)*w4;
  23                                 var x = w;
  24                                 do {
  25                                         var offset = offsetY + (x-1)*4;
  26
  27                                         if (mode) {
  28                                                 // a bit faster, but not as good
  29                                                 var d = data[offset] * 0.299 + data[offset+1] * 0.587 + data[offset+2] * 0.114;
  30                                                 var r = (d + 39);
  31                                                 var g = (d + 14);
  32                                                 var b = (d - 36);
  33                                         } else {
  34                                                 // Microsoft
  35                                                 var or = data[offset];
  36                                                 var og = data[offset+1];
  37                                                 var ob = data[offset+2];
  38
  39                                                 var r = (or * 0.393 + og * 0.769 + ob * 0.189);
  40                                                 var g = (or * 0.349 + og * 0.686 + ob * 0.168);
  41                                                 var b = (or * 0.272 + og * 0.534 + ob * 0.131);
  42                                         }
  43
  44                                         if (r < 0) r = 0; if (r > 255) r = 255;
  45                                         if (g < 0) g = 0; if (g > 255) g = 255;
  46                                         if (b < 0) b = 0; if (b > 255) b = 255;
  47
  48                                         data[offset] = r;
  49                                         data[offset+1] = g;
  50                                         data[offset+2] = b;
  51
  52                                 } while (--x);
  53                         } while (--y);
  54                         return true;
  55                 }
  56         },
  57         checkSupport : function() {
  58                 return Pixastic.Client.hasCanvasImageData();
  59         }
  60 }