35 lines
662 B
JavaScript
35 lines
662 B
JavaScript
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'use strict';
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module.exports = {
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PNG_SIGNATURE: [0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a],
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TYPE_IHDR: 0x49484452,
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TYPE_IEND: 0x49454e44,
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TYPE_IDAT: 0x49444154,
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TYPE_PLTE: 0x504c5445,
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TYPE_tRNS: 0x74524e53, // eslint-disable-line camelcase
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TYPE_gAMA: 0x67414d41, // eslint-disable-line camelcase
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// color-type bits
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COLORTYPE_GRAYSCALE: 0,
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COLORTYPE_PALETTE: 1,
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COLORTYPE_COLOR: 2,
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COLORTYPE_ALPHA: 4, // e.g. grayscale and alpha
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// color-type combinations
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COLORTYPE_PALETTE_COLOR: 3,
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COLORTYPE_COLOR_ALPHA: 6,
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COLORTYPE_TO_BPP_MAP: {
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0: 1,
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2: 3,
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3: 1,
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4: 2,
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6: 4
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},
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GAMMA_DIVISION: 100000
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};
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