Welcome to mirror list, hosted at ThFree Co, Russian Federation.

github.com/kornelski/7z.git - Unnamed repository; edit this file 'description' to name the repository.
summaryrefslogtreecommitdiff
path: root/CPP/7zip/Compress/QuantumDecoder.h
diff options
context:
space:
mode:
Diffstat (limited to 'CPP/7zip/Compress/QuantumDecoder.h')
-rw-r--r--CPP/7zip/Compress/QuantumDecoder.h228
1 files changed, 67 insertions, 161 deletions
diff --git a/CPP/7zip/Compress/QuantumDecoder.h b/CPP/7zip/Compress/QuantumDecoder.h
index c18ea2aa..afeba708 100644
--- a/CPP/7zip/Compress/QuantumDecoder.h
+++ b/CPP/7zip/Compress/QuantumDecoder.h
@@ -5,92 +5,94 @@
#include "../../Common/MyCom.h"
-#include "../ICoder.h"
-
-#include "../Common/InBuffer.h"
-
#include "LzOutWindow.h"
namespace NCompress {
namespace NQuantum {
-class CStreamBitDecoder
+class CBitDecoder
{
UInt32 Value;
- CInBuffer Stream;
+ bool _extra;
+ const Byte *_buf;
+ const Byte *_bufLim;
public:
- bool Create(UInt32 bufferSize) { return Stream.Create(bufferSize); }
- void SetStream(ISequentialInStream *stream) { Stream.SetStream(stream); }
- // void ReleaseStream() { Stream.ReleaseStream(); }
-
- void Finish() { Value = 0x10000; }
-
- void Init()
+ void SetStreamAndInit(const Byte *inData, size_t inSize)
{
- Stream.Init();
+ _buf = inData;
+ _bufLim = inData + inSize;
Value = 0x10000;
+ _extra = false;
}
- UInt64 GetProcessedSize() const { return Stream.GetProcessedSize(); }
- bool WasFinished() const { return Stream.WasFinished(); }
+ bool WasExtraRead() const { return _extra; }
+
+ bool WasFinishedOK() const
+ {
+ return !_extra && _buf == _bufLim;
+ }
UInt32 ReadBit()
{
if (Value >= 0x10000)
- Value = 0x100 | Stream.ReadByte();
+ {
+ Byte b;
+ if (_buf >= _bufLim)
+ {
+ b = 0xFF;
+ _extra = true;
+ }
+ else
+ b = *_buf++;
+ Value = 0x100 | b;
+ }
UInt32 res = (Value >> 7) & 1;
Value <<= 1;
return res;
}
- UInt32 ReadBits(int numBits) // numBits > 0
+ UInt32 ReadStart16Bits()
+ {
+ // we use check for extra read in another code.
+ UInt32 val = ((UInt32)*_buf << 8) | _buf[1];
+ _buf += 2;
+ return val;
+ }
+
+ UInt32 ReadBits(unsigned numBits) // numBits > 0
{
UInt32 res = 0;
do
res = (res << 1) | ReadBit();
- while (--numBits != 0);
+ while (--numBits);
return res;
}
};
-const unsigned kNumLitSelectorBits = 2;
-const unsigned kNumLitSelectors = (1 << kNumLitSelectorBits);
-const unsigned kNumLitSymbols = 1 << (8 - kNumLitSelectorBits);
-const unsigned kNumMatchSelectors = 3;
-const unsigned kNumSelectors = kNumLitSelectors + kNumMatchSelectors;
-const unsigned kNumSymbolsMax = kNumLitSymbols; // 64
-
-namespace NRangeCoder {
-class CDecoder
+class CRangeDecoder
{
UInt32 Low;
UInt32 Range;
UInt32 Code;
public:
- CStreamBitDecoder Stream;
- bool Create(UInt32 bufferSize) { return Stream.Create(bufferSize); }
- void SetStream(ISequentialInStream *stream) { Stream.SetStream(stream); }
- // void ReleaseStream() { Stream.ReleaseStream(); }
+ CBitDecoder Stream;
void Init()
{
- Stream.Init();
Low = 0;
Range = 0x10000;
- Code = Stream.ReadBits(16);
+ Code = Stream.ReadStart16Bits();
}
- void Finish()
+ bool Finish()
{
- // we need these extra two Bit_reads
- Stream.ReadBit();
- Stream.ReadBit();
- Stream.Finish();
+ // do all streams use these two bits at end?
+ if (Stream.ReadBit() != 0) return false;
+ if (Stream.ReadBit() != 0) return false;
+ return Stream.WasFinishedOK();
}
- UInt64 GetProcessedSize() const { return Stream.GetProcessedSize(); }
-
UInt32 GetThreshold(UInt32 total) const
{
return ((Code + 1) * total - 1) / Range; // & 0xFFFF is not required;
@@ -119,148 +121,52 @@ public:
}
};
-const UInt16 kUpdateStep = 8;
-const UInt16 kFreqSumMax = 3800;
-const UInt16 kReorderCountStart = 4;
-const UInt16 kReorderCount = 50;
+
+const unsigned kNumLitSelectorBits = 2;
+const unsigned kNumLitSelectors = (1 << kNumLitSelectorBits);
+const unsigned kNumLitSymbols = 1 << (8 - kNumLitSelectorBits);
+const unsigned kNumMatchSelectors = 3;
+const unsigned kNumSelectors = kNumLitSelectors + kNumMatchSelectors;
+const unsigned kNumSymbolsMax = kNumLitSymbols; // 64
+
class CModelDecoder
{
unsigned NumItems;
unsigned ReorderCount;
UInt16 Freqs[kNumSymbolsMax + 1];
- Byte Values[kNumSymbolsMax];
+ Byte Vals[kNumSymbolsMax];
public:
- void Init(unsigned numItems)
- {
- NumItems = numItems;
- ReorderCount = kReorderCountStart;
- for (unsigned i = 0; i < numItems; i++)
- {
- Freqs[i] = (UInt16)(numItems - i);
- Values[i] = (Byte)i;
- }
- Freqs[numItems] = 0;
- }
-
- unsigned Decode(CDecoder *rangeDecoder)
- {
- UInt32 threshold = rangeDecoder->GetThreshold(Freqs[0]);
- unsigned i;
- for (i = 1; Freqs[i] > threshold; i++);
- rangeDecoder->Decode(Freqs[i], Freqs[i - 1], Freqs[0]);
- unsigned res = Values[--i];
- do
- Freqs[i] += kUpdateStep;
- while (i-- != 0);
-
- if (Freqs[0] > kFreqSumMax)
- {
- if (--ReorderCount == 0)
- {
- ReorderCount = kReorderCount;
- for (i = 0; i < NumItems; i++)
- Freqs[i] = (UInt16)(((Freqs[i] - Freqs[i + 1]) + 1) >> 1);
- for (i = 0; i < NumItems - 1; i++)
- for (unsigned j = i + 1; j < NumItems; j++)
- if (Freqs[i] < Freqs[j])
- {
- UInt16 tmpFreq = Freqs[i];
- Byte tmpVal = Values[i];
- Freqs[i] = Freqs[j];
- Values[i] = Values[j];
- Freqs[j] = tmpFreq;
- Values[j] = tmpVal;
- }
- do
- Freqs[i] = (UInt16)(Freqs[i] + Freqs[i + 1]);
- while (i-- != 0);
- }
- else
- {
- i = NumItems - 1;
- do
- {
- Freqs[i] >>= 1;
- if (Freqs[i] <= Freqs[i + 1])
- Freqs[i] = (UInt16)(Freqs[i + 1] + 1);
- }
- while (i-- != 0);
- }
- }
- return res;
- }
+ void Init(unsigned numItems);
+ unsigned Decode(CRangeDecoder *rc);
};
-}
class CDecoder:
- public ICompressCoder,
- // public ICompressSetInStream,
- // public ICompressSetOutStreamSize,
+ public IUnknown,
public CMyUnknownImp
{
- CLzOutWindow _outWindowStream;
- // CMyComPtr<ISequentialInStream> m_InStreamRef;
- NRangeCoder::CDecoder _rangeDecoder;
+ CLzOutWindow _outWindow;
+ unsigned _numDictBits;
- UInt64 _outSize;
- int _remainLen; // -1 means end of stream. // -2 means need Init
- UInt32 _rep0;
+ CModelDecoder m_Selector;
+ CModelDecoder m_Literals[kNumLitSelectors];
+ CModelDecoder m_PosSlot[kNumMatchSelectors];
+ CModelDecoder m_LenSlot;
- int _numDictBits;
- bool _keepHistory;
-
- NRangeCoder::CModelDecoder m_Selector;
- NRangeCoder::CModelDecoder m_Literals[kNumLitSelectors];
- NRangeCoder::CModelDecoder m_PosSlot[kNumMatchSelectors];
- NRangeCoder::CModelDecoder m_LenSlot;
void Init();
- HRESULT CodeSpec(UInt32 size);
+ HRESULT CodeSpec(const Byte *inData, size_t inSize, UInt32 outSize);
public:
MY_UNKNOWN_IMP
- /*
- MY_UNKNOWN_IMP2(
- ICompressSetInStream,
- ICompressSetOutStreamSize)
- void ReleaseStreams()
- {
- _outWindowStream.ReleaseStream();
- ReleaseInStream();
- }
- */
-
- class CDecoderFlusher
- {
- CDecoder *_decoder;
- public:
- bool NeedFlush;
- CDecoderFlusher(CDecoder *decoder): _decoder(decoder), NeedFlush(true) {}
- ~CDecoderFlusher()
- {
- if (NeedFlush)
- _decoder->Flush();
- // _decoder->ReleaseStreams();
- }
- };
+ HRESULT Code(const Byte *inData, size_t inSize,
+ ISequentialOutStream *outStream, UInt32 outSize,
+ bool keepHistory);
- HRESULT Flush() { return _outWindowStream.Flush(); }
-
- HRESULT CodeReal(ISequentialInStream *inStream, ISequentialOutStream *outStream,
- const UInt64 *inSize, const UInt64 *outSize, ICompressProgressInfo *progress);
+ HRESULT SetParams(unsigned numDictBits);
- STDMETHOD(Code)(ISequentialInStream *inStream, ISequentialOutStream *outStream,
- const UInt64 *inSize, const UInt64 *outSize, ICompressProgressInfo *progress);
-
- // STDMETHOD(SetInStream)(ISequentialInStream *inStream);
- // STDMETHOD(ReleaseInStream)();
- STDMETHOD(SetOutStreamSize)(const UInt64 *outSize);
-
- HRESULT SetParams(int numDictBits);
- void SetKeepHistory(bool keepHistory) { _keepHistory = keepHistory; }
- CDecoder(): _keepHistory(false) {}
+ CDecoder(): _numDictBits(0) {}
virtual ~CDecoder() {}
};
generated by cgit v1.2.3 (git 2.25.1) at 2024-08-19 17:39:24 +0300