33 lines
694 B
Haxe
33 lines
694 B
Haxe
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package kha.audio2.ogg.tools;
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import haxe.ds.Vector;
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/**
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* ...
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* @author shohei909
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*/
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class Crc32
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{
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static inline var POLY:UInt = 0x04c11db7;
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static var table:Vector<UInt>;
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public static function init() {
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if (table != null) {
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return;
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}
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table = new Vector(256);
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for (i in 0...256) {
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var s:UInt = ((i:UInt) << (24:UInt));
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for (j in 0...8) {
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s = (s << 1) ^ (s >= ((1:UInt) << 31) ? POLY : 0);
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}
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table[i] = s;
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}
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}
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public static inline function update(crc:UInt, byte:UInt):UInt
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{
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return (crc << 8) ^ table[byte ^ (crc >>> 24)];
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}
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}
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