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This commit is contained in:
Igor Pavlov
2005-05-30 00:00:00 +00:00
committed by Kornel Lesiński
parent 8c1b5c7b7e
commit 3c510ba80b
926 changed files with 40559 additions and 23519 deletions
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67
7zip/Compress/Huffman/HuffmanDecoder.h
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@@ -1,60 +1,42 @@
// Compress/HuffmanDecoder.h
#pragma once
#ifndef __COMPRESS_HUFFMANDECODER_H
#define __COMPRESS_HUFFMANDECODER_H
#include "../../../Common/Types.h"
namespace NCompress {
namespace NHuffman {
class CDecoderException{};
const UINT32 kValueTableBits = 8;
const UInt32 kValueTableBits = 9;
template <int kNumBitsInLongestCode>
template <int kNumBitsInLongestCode, UInt32 m_NumSymbols>
class CDecoder
{
UINT32 m_Limitits[kNumBitsInLongestCode + 1]; // m_Limitits[i] = value limit for symbols with length = i
UINT32 m_Positions[kNumBitsInLongestCode + 1]; // m_Positions[i] = index in m_Symbols[] of first symbol with length = i
UINT32 m_NumSymbols;
UINT32 *m_Symbols; // symbols: at first with len = 1 then 2, ... 15.
BYTE m_Lengths[1 << kValueTableBits];
UInt32 m_Limitits[kNumBitsInLongestCode + 1]; // m_Limitits[i] = value limit for symbols with length = i
UInt32 m_Positions[kNumBitsInLongestCode + 1]; // m_Positions[i] = index in m_Symbols[] of first symbol with length = i
UInt32 m_Symbols[m_NumSymbols]; // symbols: at first with len = 1 then 2, ... 15.
Byte m_Lengths[1 << kValueTableBits];
public:
CDecoder(UINT32 numSymbols):
m_NumSymbols(numSymbols)
{ m_Symbols = new UINT32[m_NumSymbols]; }
~CDecoder()
{ delete []m_Symbols; }
void SetNumSymbols(UINT32 numSymbols)
{ m_NumSymbols = numSymbols; }
void SetCodeLengths(const BYTE *codeLengths);
void SetNumSymbols(UInt32 numSymbols) { m_NumSymbols = numSymbols; }
void SetCodeLengths(const Byte *codeLengths);
template <class TBitDecoder>
UINT32 DecodeSymbol(TBitDecoder *bitStream)
UInt32 DecodeSymbol(TBitDecoder *bitStream)
{
UINT32 numBits;
UInt32 numBits;
UINT32 value = bitStream->GetValue(kNumBitsInLongestCode);
UInt32 value = bitStream->GetValue(kNumBitsInLongestCode);
if (value < m_Limitits[kValueTableBits])
numBits = m_Lengths[value >> (kNumBitsInLongestCode - kValueTableBits)];
else if (value < m_Limitits[10])
if (value < m_Limitits[9])
numBits = 9;
else
numBits = 10;
else if (value < m_Limitits[11])
numBits = 11;
else if (value < m_Limitits[12])
numBits = 12;
else
for (numBits = 13; numBits < kNumBitsInLongestCode; numBits++)
for (numBits = kValueTableBits + 1; numBits < kNumBitsInLongestCode; numBits++)
if (value < m_Limitits[numBits])
break;
bitStream->MovePos(numBits);
UINT32 index = m_Positions[numBits] +
UInt32 index = m_Positions[numBits] +
((value - m_Limitits[numBits - 1]) >> (kNumBitsInLongestCode - numBits));
if (index >= m_NumSymbols)
throw CDecoderException(); // test it
@@ -62,27 +44,26 @@ public:
}
};
template <int kNumBitsInLongestCode>
void CDecoder<kNumBitsInLongestCode>::SetCodeLengths(const BYTE *codeLengths)
template <int kNumBitsInLongestCode, UInt32 m_NumSymbols>
void CDecoder<kNumBitsInLongestCode, m_NumSymbols>::SetCodeLengths(const Byte *codeLengths)
{
int lenCounts[kNumBitsInLongestCode + 1], tmpPositions[kNumBitsInLongestCode + 1];
int i;
for(i = 1; i <= kNumBitsInLongestCode; i++)
lenCounts[i] = 0;
UINT32 symbol;
UInt32 symbol;
for (symbol = 0; symbol < m_NumSymbols; symbol++)
{
BYTE codeLength = codeLengths[symbol];
Byte codeLength = codeLengths[symbol];
if (codeLength > kNumBitsInLongestCode)
throw CDecoderException();
lenCounts[codeLength]++;
}
lenCounts[0] = 0;
tmpPositions[0] = m_Positions[0] = m_Limitits[0] = 0;
UINT32 startPos = 0;
UINT32 index = 0;
const UINT32 kMaxValue = (1 << kNumBitsInLongestCode);
UInt32 startPos = 0;
UInt32 index = 0;
const UInt32 kMaxValue = (1 << kNumBitsInLongestCode);
for (i = 1; i <= kNumBitsInLongestCode; i++)
{
startPos += lenCounts[i] << (kNumBitsInLongestCode - i);
@@ -94,8 +75,8 @@ void CDecoder<kNumBitsInLongestCode>::SetCodeLengths(const BYTE *codeLengths)
if(i <= kValueTableBits)
{
UINT32 limit = (m_Limitits[i] >> (kNumBitsInLongestCode - kValueTableBits)); // change it
memset(m_Lengths + index, BYTE(i), limit - index);
UInt32 limit = (m_Limitits[i] >> (kNumBitsInLongestCode - kValueTableBits)); // change it
memset(m_Lengths + index, Byte(i), limit - index);
index = limit;
}
}