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17 lines
537 B
JavaScript
17 lines
537 B
JavaScript
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Grayscale = (function () {
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var Grayscale = function (src, dst) {
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var srcPixels = src.data,
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dstPixels = dst.data,
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nPixels = srcPixels.length,
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i, brightness;
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for (i = 0; i < nPixels; i += 4) {
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brightness = 0.34 * srcPixels[i] + 0.5 * srcPixels[i + 1] + 0.16 * srcPixels[i + 2];
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dstPixels[i] = brightness; // r
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dstPixels[i + 1] = brightness; // g
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dstPixels[i + 2] = brightness; // b
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dstPixels[i + 3] = srcPixels[i + 3]; // alpha
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}
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};
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return Grayscale;
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})();
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