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4.26 beta

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This commit is contained in:
Igor Pavlov
2005-08-05 00:00:00 +00:00
committed by Kornel Lesiński
parent af1fe52701
commit 31e7b924e8
56 changed files with 2185 additions and 188 deletions
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15
7zip/Compress/Huffman/HuffmanDecoder.h
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@@ -15,12 +15,11 @@ const UInt32 kValueTableBits = 9;
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_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];
public:
void SetNumSymbols(UInt32 numSymbols) { m_NumSymbols = numSymbols; }
void SetCodeLengths(const Byte *codeLengths);
template <class TBitDecoder>
UInt32 DecodeSymbol(TBitDecoder *bitStream)
@@ -29,15 +28,15 @@ public:
UInt32 value = bitStream->GetValue(kNumBitsInLongestCode);
if (value < m_Limitits[kValueTableBits])
if (value < m_Limits[kValueTableBits])
numBits = m_Lengths[value >> (kNumBitsInLongestCode - kValueTableBits)];
else
for (numBits = kValueTableBits + 1; numBits < kNumBitsInLongestCode; numBits++)
if (value < m_Limitits[numBits])
if (value < m_Limits[numBits])
break;
bitStream->MovePos(numBits);
UInt32 index = m_Positions[numBits] +
((value - m_Limitits[numBits - 1]) >> (kNumBitsInLongestCode - numBits));
((value - m_Limits[numBits - 1]) >> (kNumBitsInLongestCode - numBits));
if (index >= m_NumSymbols)
throw CDecoderException(); // test it
return m_Symbols[index];
@@ -60,7 +59,7 @@ void CDecoder<kNumBitsInLongestCode, m_NumSymbols>::SetCodeLengths(const Byte *c
lenCounts[codeLength]++;
}
lenCounts[0] = 0;
tmpPositions[0] = m_Positions[0] = m_Limitits[0] = 0;
tmpPositions[0] = m_Positions[0] = m_Limits[0] = 0;
UInt32 startPos = 0;
UInt32 index = 0;
const UInt32 kMaxValue = (1 << kNumBitsInLongestCode);
@@ -69,13 +68,13 @@ void CDecoder<kNumBitsInLongestCode, m_NumSymbols>::SetCodeLengths(const Byte *c
startPos += lenCounts[i] << (kNumBitsInLongestCode - i);
if (startPos > kMaxValue)
throw CDecoderException();
m_Limitits[i] = startPos;
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_Limitits[i] >> (kNumBitsInLongestCode - kValueTableBits)); // change it
UInt32 limit = (m_Limits[i] >> (kNumBitsInLongestCode - kValueTableBits)); // change it
memset(m_Lengths + index, Byte(i), limit - index);
index = limit;
}