Merge pull request #511 from negativeExponent/updates

[pcsx_rearmed.git] / deps / lzma-16.04 / C / Ppmd7Enc.c

/* Ppmd7Enc.c -- PPMdH Encoder\r
2015-09-28 : Igor Pavlov : Public domain\r
This code is based on PPMd var.H (2001): Dmitry Shkarin : Public domain */\r
\r
#include "Precomp.h"\r
\r
#include "Ppmd7.h"\r
\r
#define kTopValue (1 << 24)\r
\r
void Ppmd7z_RangeEnc_Init(CPpmd7z_RangeEnc *p)\r
{\r
  p->Low = 0;\r
  p->Range = 0xFFFFFFFF;\r
  p->Cache = 0;\r
  p->CacheSize = 1;\r
}\r
\r
static void RangeEnc_ShiftLow(CPpmd7z_RangeEnc *p)\r
{\r
  if ((UInt32)p->Low < (UInt32)0xFF000000 || (unsigned)(p->Low >> 32) != 0)\r
  {\r
    Byte temp = p->Cache;\r
    do\r
    {\r
      p->Stream->Write(p->Stream, (Byte)(temp + (Byte)(p->Low >> 32)));\r
      temp = 0xFF;\r
    }\r
    while (--p->CacheSize != 0);\r
    p->Cache = (Byte)((UInt32)p->Low >> 24);\r
  }\r
  p->CacheSize++;\r
  p->Low = (UInt32)p->Low << 8;\r
}\r
\r
static void RangeEnc_Encode(CPpmd7z_RangeEnc *p, UInt32 start, UInt32 size, UInt32 total)\r
{\r
  p->Low += start * (p->Range /= total);\r
  p->Range *= size;\r
  while (p->Range < kTopValue)\r
  {\r
    p->Range <<= 8;\r
    RangeEnc_ShiftLow(p);\r
  }\r
}\r
\r
static void RangeEnc_EncodeBit_0(CPpmd7z_RangeEnc *p, UInt32 size0)\r
{\r
  p->Range = (p->Range >> 14) * size0;\r
  while (p->Range < kTopValue)\r
  {\r
    p->Range <<= 8;\r
    RangeEnc_ShiftLow(p);\r
  }\r
}\r
\r
static void RangeEnc_EncodeBit_1(CPpmd7z_RangeEnc *p, UInt32 size0)\r
{\r
  UInt32 newBound = (p->Range >> 14) * size0;\r
  p->Low += newBound;\r
  p->Range -= newBound;\r
  while (p->Range < kTopValue)\r
  {\r
    p->Range <<= 8;\r
    RangeEnc_ShiftLow(p);\r
  }\r
}\r
\r
void Ppmd7z_RangeEnc_FlushData(CPpmd7z_RangeEnc *p)\r
{\r
  unsigned i;\r
  for (i = 0; i < 5; i++)\r
    RangeEnc_ShiftLow(p);\r
}\r
\r
\r
#define MASK(sym) ((signed char *)charMask)[sym]\r
\r
void Ppmd7_EncodeSymbol(CPpmd7 *p, CPpmd7z_RangeEnc *rc, int symbol)\r
{\r
  size_t charMask[256 / sizeof(size_t)];\r
  if (p->MinContext->NumStats != 1)\r
  {\r
    CPpmd_State *s = Ppmd7_GetStats(p, p->MinContext);\r
    UInt32 sum;\r
    unsigned i;\r
    if (s->Symbol == symbol)\r
    {\r
      RangeEnc_Encode(rc, 0, s->Freq, p->MinContext->SummFreq);\r
      p->FoundState = s;\r
      Ppmd7_Update1_0(p);\r
      return;\r
    }\r
    p->PrevSuccess = 0;\r
    sum = s->Freq;\r
    i = p->MinContext->NumStats - 1;\r
    do\r
    {\r
      if ((++s)->Symbol == symbol)\r
      {\r
        RangeEnc_Encode(rc, sum, s->Freq, p->MinContext->SummFreq);\r
        p->FoundState = s;\r
        Ppmd7_Update1(p);\r
        return;\r
      }\r
      sum += s->Freq;\r
    }\r
    while (--i);\r
    \r
    p->HiBitsFlag = p->HB2Flag[p->FoundState->Symbol];\r
    PPMD_SetAllBitsIn256Bytes(charMask);\r
    MASK(s->Symbol) = 0;\r
    i = p->MinContext->NumStats - 1;\r
    do { MASK((--s)->Symbol) = 0; } while (--i);\r
    RangeEnc_Encode(rc, sum, p->MinContext->SummFreq - sum, p->MinContext->SummFreq);\r
  }\r
  else\r
  {\r
    UInt16 *prob = Ppmd7_GetBinSumm(p);\r
    CPpmd_State *s = Ppmd7Context_OneState(p->MinContext);\r
    if (s->Symbol == symbol)\r
    {\r
      RangeEnc_EncodeBit_0(rc, *prob);\r
      *prob = (UInt16)PPMD_UPDATE_PROB_0(*prob);\r
      p->FoundState = s;\r
      Ppmd7_UpdateBin(p);\r
      return;\r
    }\r
    else\r
    {\r
      RangeEnc_EncodeBit_1(rc, *prob);\r
      *prob = (UInt16)PPMD_UPDATE_PROB_1(*prob);\r
      p->InitEsc = PPMD7_kExpEscape[*prob >> 10];\r
      PPMD_SetAllBitsIn256Bytes(charMask);\r
      MASK(s->Symbol) = 0;\r
      p->PrevSuccess = 0;\r
    }\r
  }\r
  for (;;)\r
  {\r
    UInt32 escFreq;\r
    CPpmd_See *see;\r
    CPpmd_State *s;\r
    UInt32 sum;\r
    unsigned i, numMasked = p->MinContext->NumStats;\r
    do\r
    {\r
      p->OrderFall++;\r
      if (!p->MinContext->Suffix)\r
        return; /* EndMarker (symbol = -1) */\r
      p->MinContext = Ppmd7_GetContext(p, p->MinContext->Suffix);\r
    }\r
    while (p->MinContext->NumStats == numMasked);\r
    \r
    see = Ppmd7_MakeEscFreq(p, numMasked, &escFreq);\r
    s = Ppmd7_GetStats(p, p->MinContext);\r
    sum = 0;\r
    i = p->MinContext->NumStats;\r
    do\r
    {\r
      int cur = s->Symbol;\r
      if (cur == symbol)\r
      {\r
        UInt32 low = sum;\r
        CPpmd_State *s1 = s;\r
        do\r
        {\r
          sum += (s->Freq & (int)(MASK(s->Symbol)));\r
          s++;\r
        }\r
        while (--i);\r
        RangeEnc_Encode(rc, low, s1->Freq, sum + escFreq);\r
        Ppmd_See_Update(see);\r
        p->FoundState = s1;\r
        Ppmd7_Update2(p);\r
        return;\r
      }\r
      sum += (s->Freq & (int)(MASK(cur)));\r
      MASK(cur) = 0;\r
      s++;\r
    }\r
    while (--i);\r
    \r
    RangeEnc_Encode(rc, sum, escFreq, sum + escFreq);\r
    see->Summ = (UInt16)(see->Summ + sum + escFreq);\r
  }\r
}\r