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#ifndef __LENCODER_H
#define __LENCODER_H
#include "BitTreeCoder.h"
#define kNumPosStatesBitsMax 4
#define kNumPosStatesMax 16
#define kNumPosStatesBitsEncodingMax 4
#define kNumPosStatesEncodingMax 16
//#define kNumMoveBits 5
#define kNumLenBits 3
#define kNumLowSymbols (1 << kNumLenBits)
#define kNumMidBits 3
#define kNumMidSymbols (1 << kNumMidBits)
#define kNumHighBits 8
#define kNumSymbolsTotal (kNumLowSymbols + kNumMidSymbols + (1 << kNumHighBits))
typedef struct LenDecoder
{
CBitDecoder m_Choice;
CBitDecoder m_Choice2;
CBitTreeDecoder m_LowCoder[kNumPosStatesMax];
CBitTreeDecoder m_MidCoder[kNumPosStatesMax];
CBitTreeDecoder m_HighCoder;
UINT32 m_NumPosStates;
} LenDecoder;
INLINE void LenDecoderCreate(LenDecoder *lenCoder, UINT32 aNumPosStates)
{
lenCoder->m_NumPosStates = aNumPosStates;
}
INLINE void LenDecoderInit(LenDecoder *lenCoder)
{
UINT32 aPosState;
BitDecoderInit(&lenCoder->m_Choice);
for (aPosState = 0; aPosState < lenCoder->m_NumPosStates; aPosState++)
{
BitTreeDecoderInit(&lenCoder->m_LowCoder[aPosState],kNumLenBits);
BitTreeDecoderInit(&lenCoder->m_MidCoder[aPosState],kNumMidBits);
}
BitTreeDecoderInit(&lenCoder->m_HighCoder,kNumHighBits);
BitDecoderInit(&lenCoder->m_Choice2);
}
INLINE UINT32 LenDecode(ISequentialInStream *in_stream, LenDecoder *lenCoder, CRangeDecoder *aRangeDecoder, UINT32 aPosState)
{
if(BitDecode(in_stream, &lenCoder->m_Choice, aRangeDecoder) == 0)
return BitTreeDecode(in_stream, &lenCoder->m_LowCoder[aPosState],aRangeDecoder);
else
{
UINT32 aSymbol = kNumLowSymbols;
if(BitDecode(in_stream, &lenCoder->m_Choice2, aRangeDecoder) == 0)
aSymbol += BitTreeDecode(in_stream, &lenCoder->m_MidCoder[aPosState],aRangeDecoder);
else
{
aSymbol += kNumMidSymbols;
aSymbol += BitTreeDecode(in_stream, &lenCoder->m_HighCoder,aRangeDecoder);
}
return aSymbol;
}
}
#endif
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