121 lines
No EOL
2.9 KiB
JavaScript
Executable file
121 lines
No EOL
2.9 KiB
JavaScript
Executable file
/*
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* Pixastic Lib - Edge detection filter - v0.1.0
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* Copyright (c) 2008 Jacob Seidelin, jseidelin@nihilogic.dk, http://blog.nihilogic.dk/
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* MIT License [http://www.opensource.org/licenses/mit-license.php]
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*/
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Pixastic.Actions.edges = {
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process : function(params) {
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var mono = !!(params.options.mono);
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var strength = 1.0;
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//if (typeof params.options.strength != "undefined")
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// strength = parseFloat(params.options.strength)||0;
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var invert = !!(params.options.invert);
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if (Pixastic.Client.hasCanvasImageData()) {
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var data = Pixastic.prepareData(params);
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var dataCopy = Pixastic.prepareData(params, true)
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var c = -strength/8;
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var kernel = [
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[c, c, c],
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[c, 1, c],
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[c, c, c]
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];
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weight = 1/c;
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var rect = params.options.rect;
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var w = rect.width;
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var h = rect.height;
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var w4 = w*4;
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var y = h;
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do {
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var offsetY = (y-1)*w4;
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var nextY = (y == h) ? y - 1 : y;
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var prevY = (y == 1) ? 0 : y-2;
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var offsetYPrev = prevY*w*4;
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var offsetYNext = nextY*w*4;
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var x = w;
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do {
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var offset = offsetY + (x*4-4);
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var offsetPrev = offsetYPrev + ((x == 1) ? 0 : x-2) * 4;
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var offsetNext = offsetYNext + ((x == w) ? x-1 : x) * 4;
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var r = ((dataCopy[offsetPrev-4]
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+ dataCopy[offsetPrev]
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+ dataCopy[offsetPrev+4]
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+ dataCopy[offset-4]
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+ dataCopy[offset+4]
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+ dataCopy[offsetNext-4]
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+ dataCopy[offsetNext]
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+ dataCopy[offsetNext+4]) * c
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+ dataCopy[offset]
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)
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* weight;
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var g = ((dataCopy[offsetPrev-3]
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+ dataCopy[offsetPrev+1]
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+ dataCopy[offsetPrev+5]
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+ dataCopy[offset-3]
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+ dataCopy[offset+5]
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+ dataCopy[offsetNext-3]
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+ dataCopy[offsetNext+1]
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+ dataCopy[offsetNext+5]) * c
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+ dataCopy[offset+1])
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* weight;
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var b = ((dataCopy[offsetPrev-2]
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+ dataCopy[offsetPrev+2]
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+ dataCopy[offsetPrev+6]
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+ dataCopy[offset-2]
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+ dataCopy[offset+6]
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+ dataCopy[offsetNext-2]
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+ dataCopy[offsetNext+2]
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+ dataCopy[offsetNext+6]) * c
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+ dataCopy[offset+2])
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* weight;
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if (mono) {
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var brightness = (r*0.3 + g*0.59 + b*0.11)||0;
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if (invert) brightness = 255 - brightness;
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if (brightness < 0 ) brightness = 0;
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if (brightness > 255 ) brightness = 255;
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r = g = b = brightness;
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} else {
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if (invert) {
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r = 255 - r;
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g = 255 - g;
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b = 255 - b;
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}
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if (r < 0 ) r = 0;
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if (g < 0 ) g = 0;
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if (b < 0 ) b = 0;
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if (r > 255 ) r = 255;
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if (g > 255 ) g = 255;
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if (b > 255 ) b = 255;
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}
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data[offset] = r;
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data[offset+1] = g;
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data[offset+2] = b;
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} while (--x);
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} while (--y);
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return true;
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}
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},
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checkSupport : function() {
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return Pixastic.Client.hasCanvasImageData();
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}
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} |