4.27 beta

7zip/Compress/Rar29/Original/model.hpp

@@ -0,0 +1,126 @@
+#ifndef _RAR_PPMMODEL_
+#define _RAR_PPMMODEL_
+
+#include "coder.hpp"
+#include "suballoc.hpp"
+
+const int MAX_O=64;                   /* maximum allowed model order */
+
+const int INT_BITS=7, PERIOD_BITS=7, TOT_BITS=INT_BITS+PERIOD_BITS,
+          INTERVAL=1 << INT_BITS, BIN_SCALE=1 << TOT_BITS, MAX_FREQ=124;
+
+#pragma pack(1)
+
+struct SEE2_CONTEXT
+{ // SEE-contexts for PPM-contexts with masked symbols
+  ushort Summ;
+  byte Shift, Count;
+  void init(int InitVal)
+  {
+    Summ=InitVal << (Shift=PERIOD_BITS-4);
+    Count=4;
+  }
+  uint getMean()
+  {
+    uint RetVal=SHORT16(Summ) >> Shift;
+    Summ -= RetVal;
+    return RetVal+(RetVal == 0);
+  }
+  void update()
+  {
+    if (Shift < PERIOD_BITS && --Count == 0)
+    {
+      Summ += Summ;
+      Count=3 << Shift++;
+    }
+  }
+};
+
+
+class ModelPPM;
+struct PPM_CONTEXT;
+
+struct STATE
+{
+  byte Symbol;
+  byte Freq;
+  PPM_CONTEXT* Successor;
+};
+
+struct FreqData
+{
+  ushort SummFreq;
+  STATE _PACK_ATTR * Stats;
+};
+
+struct PPM_CONTEXT 
+{
+    ushort NumStats;
+    union
+    {
+      FreqData U;
+      STATE OneState;
+    };
+
+    PPM_CONTEXT* Suffix;
+    inline void encodeBinSymbol(ModelPPM *Model,int symbol);  // MaxOrder:
+    inline void encodeSymbol1(ModelPPM *Model,int symbol);    //  ABCD    context
+    inline void encodeSymbol2(ModelPPM *Model,int symbol);    //   BCD    suffix
+    inline void decodeBinSymbol(ModelPPM *Model);  //   BCDE   successor
+    inline bool decodeSymbol1(ModelPPM *Model);    // other orders:
+    inline bool decodeSymbol2(ModelPPM *Model);    //   BCD    context
+    inline void update1(ModelPPM *Model,STATE* p); //    CD    suffix
+    inline void update2(ModelPPM *Model,STATE* p); //   BCDE   successor
+    void rescale(ModelPPM *Model);
+    inline PPM_CONTEXT* createChild(ModelPPM *Model,STATE* pStats,STATE& FirstState);
+    inline SEE2_CONTEXT* makeEscFreq2(ModelPPM *Model,int Diff);
+};
+#ifdef _AIX
+#pragma pack(pop)
+#else
+#pragma pack()
+#endif
+
+const uint UNIT_SIZE=sizeof(PPM_CONTEXT);
+const uint FIXED_UNIT_SIZE=12;
+
+/*
+inline PPM_CONTEXT::PPM_CONTEXT(STATE* pStats,PPM_CONTEXT* ShorterContext):
+        NumStats(1), Suffix(ShorterContext) { pStats->Successor=this; }
+inline PPM_CONTEXT::PPM_CONTEXT(): NumStats(0) {}
+*/
+
+template <class T>
+inline void _PPMD_SWAP(T& t1,T& t2) { T tmp=t1; t1=t2; t2=tmp; }
+
+
+class ModelPPM
+{
+  private:
+    friend struct PPM_CONTEXT;
+    
+    _PACK_ATTR SEE2_CONTEXT SEE2Cont[25][16], DummySEE2Cont;
+    
+    struct PPM_CONTEXT *MinContext, *MedContext, *MaxContext;
+    STATE* FoundState;      // found next state transition
+    int NumMasked, InitEsc, OrderFall, MaxOrder, RunLength, InitRL;
+    byte CharMask[256], NS2Indx[256], NS2BSIndx[256], HB2Flag[256];
+    byte EscCount, PrevSuccess, HiBitsFlag;
+    ushort BinSumm[128][64];               // binary SEE-contexts
+
+    RangeCoder Coder;
+    SubAllocator SubAlloc;
+
+    void RestartModelRare();
+    void StartModelRare(int MaxOrder);
+    inline PPM_CONTEXT* CreateSuccessors(bool Skip,STATE* p1);
+
+    inline void UpdateModel();
+    inline void ClearMask();
+  public:
+    ModelPPM();
+    bool DecodeInit(Unpack *UnpackRead,int &EscChar);
+    int DecodeChar();
+};
+
+#endif