1 /* Ppmd8.h -- PPMdI codec 2 2011-01-27 : Igor Pavlov : Public domain 3 This code is based on: 4 PPMd var.I (2002): Dmitry Shkarin : Public domain 5 Carryless rangecoder (1999): Dmitry Subbotin : Public domain */ 6 7 #ifndef __PPMD8_H 8 #define __PPMD8_H 9 10 #include "Ppmd.h" 11 12 EXTERN_C_BEGIN 13 14 #define PPMD8_MIN_ORDER 2 15 #define PPMD8_MAX_ORDER 16 16 17 struct CPpmd8_Context_; 18 19 typedef 20 #ifdef PPMD_32BIT 21 struct CPpmd8_Context_ * 22 #else 23 UInt32 24 #endif 25 CPpmd8_Context_Ref; 26 27 #pragma pack(push, 1) 28 29 typedef struct CPpmd8_Context_ 30 { 31 Byte NumStats; 32 Byte Flags; 33 UInt16 SummFreq; 34 CPpmd_State_Ref Stats; 35 CPpmd8_Context_Ref Suffix; 36 } CPpmd8_Context; 37 38 #pragma pack(pop) 39 40 #define Ppmd8Context_OneState(p) ((CPpmd_State *)&(p)->SummFreq) 41 42 /* The BUG in Shkarin's code for FREEZE mode was fixed, but that fixed 43 code is not compatible with original code for some files compressed 44 in FREEZE mode. So we disable FREEZE mode support. */ 45 46 enum 47 { 48 PPMD8_RESTORE_METHOD_RESTART, 49 PPMD8_RESTORE_METHOD_CUT_OFF 50 #ifdef PPMD8_FREEZE_SUPPORT 51 , PPMD8_RESTORE_METHOD_FREEZE 52 #endif 53 }; 54 55 typedef struct 56 { 57 CPpmd8_Context *MinContext, *MaxContext; 58 CPpmd_State *FoundState; 59 unsigned OrderFall, InitEsc, PrevSuccess, MaxOrder; 60 Int32 RunLength, InitRL; /* must be 32-bit at least */ 61 62 UInt32 Size; 63 UInt32 GlueCount; 64 Byte *Base, *LoUnit, *HiUnit, *Text, *UnitsStart; 65 UInt32 AlignOffset; 66 unsigned RestoreMethod; 67 68 /* Range Coder */ 69 UInt32 Range; 70 UInt32 Code; 71 UInt32 Low; 72 union 73 { 74 IByteIn *In; 75 IByteOut *Out; 76 } Stream; 77 78 Byte Indx2Units[PPMD_NUM_INDEXES]; 79 Byte Units2Indx[128]; 80 CPpmd_Void_Ref FreeList[PPMD_NUM_INDEXES]; 81 UInt32 Stamps[PPMD_NUM_INDEXES]; 82 83 Byte NS2BSIndx[256], NS2Indx[260]; 84 CPpmd_See DummySee, See[24][32]; 85 UInt16 BinSumm[25][64]; 86 } CPpmd8; 87 88 void Ppmd8_Construct(CPpmd8 *p); 89 Bool Ppmd8_Alloc(CPpmd8 *p, UInt32 size, ISzAlloc *alloc); 90 void Ppmd8_Free(CPpmd8 *p, ISzAlloc *alloc); 91 void Ppmd8_Init(CPpmd8 *p, unsigned maxOrder, unsigned restoreMethod); 92 #define Ppmd8_WasAllocated(p) ((p)->Base != NULL) 93 94 95 /* ---------- Internal Functions ---------- */ 96 97 extern const Byte PPMD8_kExpEscape[16]; 98 99 #ifdef PPMD_32BIT 100 #define Ppmd8_GetPtr(p, ptr) (ptr) 101 #define Ppmd8_GetContext(p, ptr) (ptr) 102 #define Ppmd8_GetStats(p, ctx) ((ctx)->Stats) 103 #else 104 #define Ppmd8_GetPtr(p, offs) ((void *)((p)->Base + (offs))) 105 #define Ppmd8_GetContext(p, offs) ((CPpmd8_Context *)Ppmd8_GetPtr((p), (offs))) 106 #define Ppmd8_GetStats(p, ctx) ((CPpmd_State *)Ppmd8_GetPtr((p), ((ctx)->Stats))) 107 #endif 108 109 void Ppmd8_Update1(CPpmd8 *p); 110 void Ppmd8_Update1_0(CPpmd8 *p); 111 void Ppmd8_Update2(CPpmd8 *p); 112 void Ppmd8_UpdateBin(CPpmd8 *p); 113 114 #define Ppmd8_GetBinSumm(p) \ 115 &p->BinSumm[p->NS2Indx[Ppmd8Context_OneState(p->MinContext)->Freq - 1]][ \ 116 p->NS2BSIndx[Ppmd8_GetContext(p, p->MinContext->Suffix)->NumStats] + \ 117 p->PrevSuccess + p->MinContext->Flags + ((p->RunLength >> 26) & 0x20)] 118 119 CPpmd_See *Ppmd8_MakeEscFreq(CPpmd8 *p, unsigned numMasked, UInt32 *scale); 120 121 122 /* ---------- Decode ---------- */ 123 124 Bool Ppmd8_RangeDec_Init(CPpmd8 *p); 125 #define Ppmd8_RangeDec_IsFinishedOK(p) ((p)->Code == 0) 126 int Ppmd8_DecodeSymbol(CPpmd8 *p); /* returns: -1 as EndMarker, -2 as DataError */ 127 128 129 /* ---------- Encode ---------- */ 130 131 #define Ppmd8_RangeEnc_Init(p) { (p)->Low = 0; (p)->Range = 0xFFFFFFFF; } 132 void Ppmd8_RangeEnc_FlushData(CPpmd8 *p); 133 void Ppmd8_EncodeSymbol(CPpmd8 *p, int symbol); /* symbol = -1 means EndMarker */ 134 135 EXTERN_C_END 136 137 #endif 138