| 1 | ;
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| 2 |
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| 3 | module.exports = function paethPredictor(left, above, upLeft) {
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| 4 | let paeth = left + above - upLeft;
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| 5 | let pLeft = Math.abs(paeth - left);
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| 6 | let pAbove = Math.abs(paeth - above);
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| 7 | let pUpLeft = Math.abs(paeth - upLeft);
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| 8 |
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| 9 | if (pLeft <= pAbove && pLeft <= pUpLeft) {
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| 10 | return left;
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| 11 | }
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| 12 | if (pAbove <= pUpLeft) {
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| 13 | return above;
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| 14 | }
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| 15 | return upLeft;
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| 16 | };
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