diff options
Diffstat (limited to 'C/Ppmd8.c')
| -rw-r--r-- | C/Ppmd8.c | 33 |
1 files changed, 21 insertions, 12 deletions
@@ -1,5 +1,5 @@ /* Ppmd8.c -- PPMdI codec -2023-04-02 : Igor Pavlov : Public domain +2023-09-07 : Igor Pavlov : Public domain This code is based on PPMd var.I (2002): Dmitry Shkarin : Public domain */ #include "Precomp.h" @@ -302,8 +302,17 @@ static void *Ppmd8_AllocUnits(CPpmd8 *p, unsigned indx) #define MEM_12_CPY(dest, src, num) \ - { UInt32 *d = (UInt32 *)dest; const UInt32 *z = (const UInt32 *)src; UInt32 n = num; \ - do { d[0] = z[0]; d[1] = z[1]; d[2] = z[2]; z += 3; d += 3; } while (--n); } + { UInt32 *d = (UInt32 *)(dest); \ + const UInt32 *z = (const UInt32 *)(src); \ + unsigned n = (num); \ + do { \ + d[0] = z[0]; \ + d[1] = z[1]; \ + d[2] = z[2]; \ + z += 3; \ + d += 3; \ + } while (--n); \ + } @@ -1215,8 +1224,8 @@ void Ppmd8_UpdateModel(CPpmd8 *p) if ((ns1 & 1) != 0) { /* Expand for one UNIT */ - unsigned oldNU = (ns1 + 1) >> 1; - unsigned i = U2I(oldNU); + const unsigned oldNU = (ns1 + 1) >> 1; + const unsigned i = U2I(oldNU); if (i != U2I((size_t)oldNU + 1)) { void *ptr = Ppmd8_AllocUnits(p, i + 1); @@ -1235,7 +1244,7 @@ void Ppmd8_UpdateModel(CPpmd8 *p) sum = c->Union2.SummFreq; /* max increase of Escape_Freq is 1 here. an average increase is 1/3 per symbol */ - sum += (3 * ns1 + 1 < ns); + sum += (UInt32)(unsigned)(3 * ns1 + 1 < ns); /* original PPMdH uses 16-bit variable for (sum) here. But (sum < ???). Do we need to truncate (sum) to 16-bit */ // sum = (UInt16)sum; @@ -1265,7 +1274,7 @@ void Ppmd8_UpdateModel(CPpmd8 *p) s->Freq = (Byte)freq; - sum = freq + p->InitEsc + (ns > 2); // Ppmd8 (> 2) + sum = (UInt32)(freq + p->InitEsc + (ns > 2)); // Ppmd8 (> 2) } } @@ -1437,10 +1446,10 @@ CPpmd_See *Ppmd8_MakeEscFreq(CPpmd8 *p, unsigned numMasked1, UInt32 *escFreq) { // if (see->Summ) field is larger than 16-bit, we need only low 16 bits of Summ - unsigned summ = (UInt16)see->Summ; // & 0xFFFF - unsigned r = (summ >> see->Shift); + const unsigned summ = (UInt16)see->Summ; // & 0xFFFF + const unsigned r = (summ >> see->Shift); see->Summ = (UInt16)(summ - r); - *escFreq = r + (r == 0); + *escFreq = (UInt32)(r + (r == 0)); } } else @@ -1485,9 +1494,9 @@ void Ppmd8_Update1_0(CPpmd8 *p) CPpmd_State *s = p->FoundState; CPpmd8_Context *mc = p->MinContext; unsigned freq = s->Freq; - unsigned summFreq = mc->Union2.SummFreq; + const unsigned summFreq = mc->Union2.SummFreq; p->PrevSuccess = (2 * freq >= summFreq); // Ppmd8 (>=) - p->RunLength += (int)p->PrevSuccess; + p->RunLength += (Int32)p->PrevSuccess; mc->Union2.SummFreq = (UInt16)(summFreq + 4); freq += 4; s->Freq = (Byte)freq; |