49 lines
1.2 KiB
C++
49 lines
1.2 KiB
C++
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inline unsigned int RangeCoder::GetChar()
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{
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return(UnpackRead->GetChar());
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}
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void RangeCoder::InitDecoder(Unpack *UnpackRead)
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{
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RangeCoder::UnpackRead=UnpackRead;
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low=code=0;
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range=uint(-1);
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for (int i=0;i < 4;i++)
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code=(code << 8) | GetChar();
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}
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// (int) cast before "low" added only to suppress compiler warnings.
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#define ARI_DEC_NORMALIZE(code,low,range,read) \
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{ \
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while ((low^(low+range))<TOP || range<BOT && ((range=-(int)low&(BOT-1)),1)) \
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{ \
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code=(code << 8) | read->GetChar(); \
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range <<= 8; \
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low <<= 8; \
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} \
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}
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inline int RangeCoder::GetCurrentCount()
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{
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return (code-low)/(range /= SubRange.scale);
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}
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inline uint RangeCoder::GetCurrentShiftCount(uint SHIFT)
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{
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return (code-low)/(range >>= SHIFT);
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}
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inline void RangeCoder::Decode()
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{
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low += range*SubRange.LowCount;
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range *= SubRange.HighCount-SubRange.LowCount;
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}
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