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]
7 Pixastic.Actions.sharpen = {
8 process : function(params) {
11 if (typeof params.options.amount != "undefined")
12 strength = parseFloat(params.options.amount)||0;
14 if (strength < 0) strength = 0;
15 if (strength > 1) strength = 1;
17 if (Pixastic.Client.hasCanvasImageData()) {
18 var data = Pixastic.prepareData(params);
19 var dataCopy = Pixastic.prepareData(params, true)
22 var mulOther = 1 + 3*strength;
26 [-mulOther, mul, -mulOther],
31 for (var i=0;i<3;i++) {
32 for (var j=0;j<3;j++) {
33 weight += kernel[i][j];
39 var rect = params.options.rect;
49 var offsetY = (y-1)*w4;
51 var nextY = (y == h) ? y - 1 : y;
52 var prevY = (y == 1) ? 0 : y-2;
54 var offsetYPrev = prevY*w4;
55 var offsetYNext = nextY*w4;
59 var offset = offsetY + (x*4-4);
61 var offsetPrev = offsetYPrev + ((x == 1) ? 0 : x-2) * 4;
62 var offsetNext = offsetYNext + ((x == w) ? x-1 : x) * 4;
65 - dataCopy[offsetPrev]
68 - dataCopy[offsetNext]) * mulOther
69 + dataCopy[offset] * mul
73 - dataCopy[offsetPrev+1]
76 - dataCopy[offsetNext+1]) * mulOther
77 + dataCopy[offset+1] * mul
81 - dataCopy[offsetPrev+2]
84 - dataCopy[offsetNext+2]) * mulOther
85 + dataCopy[offset+2] * mul
92 if (r > 255 ) r = 255;
93 if (g > 255 ) g = 255;
94 if (b > 255 ) b = 255;
107 checkSupport : function() {
108 return Pixastic.Client.hasCanvasImageData();