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

   1 /*
   2  * Pixastic Lib - Sharpen 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.sharpen = {
   8         process : function(params) {
   9
  10                 var strength = 0;
  11                 if (typeof params.options.amount != "undefined")
  12                         strength = parseFloat(params.options.amount)||0;
  13
  14                 if (strength < 0) strength = 0;
  15                 if (strength > 1) strength = 1;
  16
  17                 if (Pixastic.Client.hasCanvasImageData()) {
  18                         var data = Pixastic.prepareData(params);
  19                         var dataCopy = Pixastic.prepareData(params, true)
  20
  21                         var mul = 15;
  22                         var mulOther = 1 + 3*strength;
  23
  24                         var kernel = [
  25                                 [0,     -mulOther,      0],
  26                                 [-mulOther,     mul,    -mulOther],
  27                                 [0,     -mulOther,      0]
  28                         ];
  29
  30                         var weight = 0;
  31                         for (var i=0;i<3;i++) {
  32                                 for (var j=0;j<3;j++) {
  33                                         weight += kernel[i][j];
  34                                 }
  35                         }
  36
  37                         weight = 1 / weight;
  38
  39                         var rect = params.options.rect;
  40                         var w = rect.width;
  41                         var h = rect.height;
  42
  43                         mul *= weight;
  44                         mulOther *= weight;
  45
  46                         var w4 = w*4;
  47                         var y = h;
  48                         do {
  49                                 var offsetY = (y-1)*w4;
  50
  51                                 var nextY = (y == h) ? y - 1 : y;
  52                                 var prevY = (y == 1) ? 0 : y-2;
  53
  54                                 var offsetYPrev = prevY*w4;
  55                                 var offsetYNext = nextY*w4;
  56
  57                                 var x = w;
  58                                 do {
  59                                         var offset = offsetY + (x*4-4);
  60
  61                                         var offsetPrev = offsetYPrev + ((x == 1) ? 0 : x-2) * 4;
  62                                         var offsetNext = offsetYNext + ((x == w) ? x-1 : x) * 4;
  63
  64                                         var r = ((
  65                                                 - dataCopy[offsetPrev]
  66                                                 - dataCopy[offset-4]
  67                                                 - dataCopy[offset+4]
  68                                                 - dataCopy[offsetNext])         * mulOther
  69                                                 + dataCopy[offset]      * mul
  70                                                 );
  71
  72                                         var g = ((
  73                                                 - dataCopy[offsetPrev+1]
  74                                                 - dataCopy[offset-3]
  75                                                 - dataCopy[offset+5]
  76                                                 - dataCopy[offsetNext+1])       * mulOther
  77                                                 + dataCopy[offset+1]    * mul
  78                                                 );
  79
  80                                         var b = ((
  81                                                 - dataCopy[offsetPrev+2]
  82                                                 - dataCopy[offset-2]
  83                                                 - dataCopy[offset+6]
  84                                                 - dataCopy[offsetNext+2])       * mulOther
  85                                                 + dataCopy[offset+2]    * mul
  86                                                 );
  87
  88
  89                                         if (r < 0 ) r = 0;
  90                                         if (g < 0 ) g = 0;
  91                                         if (b < 0 ) b = 0;
  92                                         if (r > 255 ) r = 255;
  93                                         if (g > 255 ) g = 255;
  94                                         if (b > 255 ) b = 255;
  95
  96                                         data[offset] = r;
  97                                         data[offset+1] = g;
  98                                         data[offset+2] = b;
  99
 100                                 } while (--x);
 101                         } while (--y);
 102
 103                         return true;
 104
 105                 }
 106         },
 107         checkSupport : function() {
 108                 return Pixastic.Client.hasCanvasImageData();
 109         }
 110 }