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4.27 beta

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This commit is contained in:
Igor Pavlov
2005-09-21 00:00:00 +00:00
committed by Kornel Lesiński
parent 31e7b924e8
commit d66cf2fcf3
393 changed files with 17345 additions and 4743 deletions
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125
7zip/Compress/Huffman/HuffmanDecoder.h
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@@ -8,86 +8,81 @@
namespace NCompress {
namespace NHuffman {
class CDecoderException{};
const int kNumTableBits = 9;
const UInt32 kValueTableBits = 9;
template <int kNumBitsInLongestCode, UInt32 m_NumSymbols>
template <int kNumBitsMax, UInt32 m_NumSymbols>
class CDecoder
{
UInt32 m_Limits[kNumBitsInLongestCode + 1]; // m_Limits[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];
UInt32 m_Limits[kNumBitsMax + 1]; // m_Limits[i] = value limit for symbols with length = i
UInt32 m_Positions[kNumBitsMax + 1]; // m_Positions[i] = index in m_Symbols[] of first symbol with length = i
UInt32 m_Symbols[m_NumSymbols];
Byte m_Lengths[1 << kNumTableBits]; // Table oh length for short codes.
public:
void SetCodeLengths(const Byte *codeLengths);
bool SetCodeLengths(const Byte *codeLengths)
{
int lenCounts[kNumBitsMax + 1], tmpPositions[kNumBitsMax + 1];
int i;
for(i = 1; i <= kNumBitsMax; i++)
lenCounts[i] = 0;
UInt32 symbol;
for (symbol = 0; symbol < m_NumSymbols; symbol++)
{
int len = codeLengths[symbol];
if (len > kNumBitsMax)
return false;
lenCounts[len]++;
m_Symbols[symbol] = 0xFFFFFFFF;
}
lenCounts[0] = 0;
m_Positions[0] = m_Limits[0] = 0;
UInt32 startPos = 0;
UInt32 index = 0;
const UInt32 kMaxValue = (1 << kNumBitsMax);
for (i = 1; i <= kNumBitsMax; i++)
{
startPos += lenCounts[i] << (kNumBitsMax - i);
if (startPos > kMaxValue)
return false;
m_Limits[i] = (i == kNumBitsMax) ? kMaxValue : startPos;
m_Positions[i] = m_Positions[i - 1] + lenCounts[i - 1];
tmpPositions[i] = m_Positions[i];
if(i <= kNumTableBits)
{
UInt32 limit = (m_Limits[i] >> (kNumBitsMax - kNumTableBits));
for (; index < limit; index++)
m_Lengths[index] = (Byte)i;
}
}
for (symbol = 0; symbol < m_NumSymbols; symbol++)
{
int len = codeLengths[symbol];
if (len != 0)
m_Symbols[tmpPositions[len]++] = symbol;
}
return true;
}
template <class TBitDecoder>
UInt32 DecodeSymbol(TBitDecoder *bitStream)
{
UInt32 numBits;
UInt32 value = bitStream->GetValue(kNumBitsInLongestCode);
if (value < m_Limits[kValueTableBits])
numBits = m_Lengths[value >> (kNumBitsInLongestCode - kValueTableBits)];
int numBits;
UInt32 value = bitStream->GetValue(kNumBitsMax);
if (value < m_Limits[kNumTableBits])
numBits = m_Lengths[value >> (kNumBitsMax - kNumTableBits)];
else
for (numBits = kValueTableBits + 1; numBits < kNumBitsInLongestCode; numBits++)
if (value < m_Limits[numBits])
break;
for (numBits = kNumTableBits + 1; value >= m_Limits[numBits]; numBits++);
bitStream->MovePos(numBits);
UInt32 index = m_Positions[numBits] +
((value - m_Limits[numBits - 1]) >> (kNumBitsInLongestCode - numBits));
((value - m_Limits[numBits - 1]) >> (kNumBitsMax - numBits));
if (index >= m_NumSymbols)
throw CDecoderException(); // test it
// throw CDecoderException(); // test it
return 0xFFFFFFFF;
return m_Symbols[index];
}
};
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;
for (symbol = 0; symbol < m_NumSymbols; symbol++)
{
Byte codeLength = codeLengths[symbol];
if (codeLength > kNumBitsInLongestCode)
throw CDecoderException();
lenCounts[codeLength]++;
}
lenCounts[0] = 0;
tmpPositions[0] = m_Positions[0] = m_Limits[0] = 0;
UInt32 startPos = 0;
UInt32 index = 0;
const UInt32 kMaxValue = (1 << kNumBitsInLongestCode);
for (i = 1; i <= kNumBitsInLongestCode; i++)
{
startPos += lenCounts[i] << (kNumBitsInLongestCode - i);
if (startPos > kMaxValue)
throw CDecoderException();
m_Limits[i] = startPos;
m_Positions[i] = m_Positions[i - 1] + lenCounts[i - 1];
tmpPositions[i] = m_Positions[i];
if(i <= kValueTableBits)
{
UInt32 limit = (m_Limits[i] >> (kNumBitsInLongestCode - kValueTableBits)); // change it
memset(m_Lengths + index, Byte(i), limit - index);
index = limit;
}
}
// if (startPos != kMaxValue)
// throw CDecoderException();
for (symbol = 0; symbol < m_NumSymbols; symbol++)
if (codeLengths[symbol] != 0)
m_Symbols[tmpPositions[codeLengths[symbol]]++] = symbol;
}
}}
#endif