17 lines
486 B
JavaScript
17 lines
486 B
JavaScript
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this.onmessage = function (event) {
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var imagedata = event.data.imgData,
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intensity = event.data.intensity,
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px = imagedata.data,
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grey = null,
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length = px.length;
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for (var i = 0; i < length; i += 4) {
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var k = px[i] * 0.3 + px[i + 1] * 0.59 + px[i + 2] * 0.11;
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px[i] = ~~ (k * intensity + px[i] * (1 - intensity));
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px[i + 1] = ~~ (k * intensity + px[i + 1] * (1 - intensity));
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px[i + 2] = ~~ (k * intensity + px[i + 2] * (1 - intensity));
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}
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postMessage(imagedata);
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};
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