ce188d4d |
1 | /* Ppmd7Enc.c -- PPMdH Encoder\r |
2 | 2015-09-28 : Igor Pavlov : Public domain\r |
3 | This code is based on PPMd var.H (2001): Dmitry Shkarin : Public domain */\r |
4 | \r |
5 | #include "Precomp.h"\r |
6 | \r |
7 | #include "Ppmd7.h"\r |
8 | \r |
9 | #define kTopValue (1 << 24)\r |
10 | \r |
11 | void Ppmd7z_RangeEnc_Init(CPpmd7z_RangeEnc *p)\r |
12 | {\r |
13 | p->Low = 0;\r |
14 | p->Range = 0xFFFFFFFF;\r |
15 | p->Cache = 0;\r |
16 | p->CacheSize = 1;\r |
17 | }\r |
18 | \r |
19 | static void RangeEnc_ShiftLow(CPpmd7z_RangeEnc *p)\r |
20 | {\r |
21 | if ((UInt32)p->Low < (UInt32)0xFF000000 || (unsigned)(p->Low >> 32) != 0)\r |
22 | {\r |
23 | Byte temp = p->Cache;\r |
24 | do\r |
25 | {\r |
26 | p->Stream->Write(p->Stream, (Byte)(temp + (Byte)(p->Low >> 32)));\r |
27 | temp = 0xFF;\r |
28 | }\r |
29 | while (--p->CacheSize != 0);\r |
30 | p->Cache = (Byte)((UInt32)p->Low >> 24);\r |
31 | }\r |
32 | p->CacheSize++;\r |
33 | p->Low = (UInt32)p->Low << 8;\r |
34 | }\r |
35 | \r |
36 | static void RangeEnc_Encode(CPpmd7z_RangeEnc *p, UInt32 start, UInt32 size, UInt32 total)\r |
37 | {\r |
38 | p->Low += start * (p->Range /= total);\r |
39 | p->Range *= size;\r |
40 | while (p->Range < kTopValue)\r |
41 | {\r |
42 | p->Range <<= 8;\r |
43 | RangeEnc_ShiftLow(p);\r |
44 | }\r |
45 | }\r |
46 | \r |
47 | static void RangeEnc_EncodeBit_0(CPpmd7z_RangeEnc *p, UInt32 size0)\r |
48 | {\r |
49 | p->Range = (p->Range >> 14) * size0;\r |
50 | while (p->Range < kTopValue)\r |
51 | {\r |
52 | p->Range <<= 8;\r |
53 | RangeEnc_ShiftLow(p);\r |
54 | }\r |
55 | }\r |
56 | \r |
57 | static void RangeEnc_EncodeBit_1(CPpmd7z_RangeEnc *p, UInt32 size0)\r |
58 | {\r |
59 | UInt32 newBound = (p->Range >> 14) * size0;\r |
60 | p->Low += newBound;\r |
61 | p->Range -= newBound;\r |
62 | while (p->Range < kTopValue)\r |
63 | {\r |
64 | p->Range <<= 8;\r |
65 | RangeEnc_ShiftLow(p);\r |
66 | }\r |
67 | }\r |
68 | \r |
69 | void Ppmd7z_RangeEnc_FlushData(CPpmd7z_RangeEnc *p)\r |
70 | {\r |
71 | unsigned i;\r |
72 | for (i = 0; i < 5; i++)\r |
73 | RangeEnc_ShiftLow(p);\r |
74 | }\r |
75 | \r |
76 | \r |
77 | #define MASK(sym) ((signed char *)charMask)[sym]\r |
78 | \r |
79 | void Ppmd7_EncodeSymbol(CPpmd7 *p, CPpmd7z_RangeEnc *rc, int symbol)\r |
80 | {\r |
81 | size_t charMask[256 / sizeof(size_t)];\r |
82 | if (p->MinContext->NumStats != 1)\r |
83 | {\r |
84 | CPpmd_State *s = Ppmd7_GetStats(p, p->MinContext);\r |
85 | UInt32 sum;\r |
86 | unsigned i;\r |
87 | if (s->Symbol == symbol)\r |
88 | {\r |
89 | RangeEnc_Encode(rc, 0, s->Freq, p->MinContext->SummFreq);\r |
90 | p->FoundState = s;\r |
91 | Ppmd7_Update1_0(p);\r |
92 | return;\r |
93 | }\r |
94 | p->PrevSuccess = 0;\r |
95 | sum = s->Freq;\r |
96 | i = p->MinContext->NumStats - 1;\r |
97 | do\r |
98 | {\r |
99 | if ((++s)->Symbol == symbol)\r |
100 | {\r |
101 | RangeEnc_Encode(rc, sum, s->Freq, p->MinContext->SummFreq);\r |
102 | p->FoundState = s;\r |
103 | Ppmd7_Update1(p);\r |
104 | return;\r |
105 | }\r |
106 | sum += s->Freq;\r |
107 | }\r |
108 | while (--i);\r |
109 | \r |
110 | p->HiBitsFlag = p->HB2Flag[p->FoundState->Symbol];\r |
111 | PPMD_SetAllBitsIn256Bytes(charMask);\r |
112 | MASK(s->Symbol) = 0;\r |
113 | i = p->MinContext->NumStats - 1;\r |
114 | do { MASK((--s)->Symbol) = 0; } while (--i);\r |
115 | RangeEnc_Encode(rc, sum, p->MinContext->SummFreq - sum, p->MinContext->SummFreq);\r |
116 | }\r |
117 | else\r |
118 | {\r |
119 | UInt16 *prob = Ppmd7_GetBinSumm(p);\r |
120 | CPpmd_State *s = Ppmd7Context_OneState(p->MinContext);\r |
121 | if (s->Symbol == symbol)\r |
122 | {\r |
123 | RangeEnc_EncodeBit_0(rc, *prob);\r |
124 | *prob = (UInt16)PPMD_UPDATE_PROB_0(*prob);\r |
125 | p->FoundState = s;\r |
126 | Ppmd7_UpdateBin(p);\r |
127 | return;\r |
128 | }\r |
129 | else\r |
130 | {\r |
131 | RangeEnc_EncodeBit_1(rc, *prob);\r |
132 | *prob = (UInt16)PPMD_UPDATE_PROB_1(*prob);\r |
133 | p->InitEsc = PPMD7_kExpEscape[*prob >> 10];\r |
134 | PPMD_SetAllBitsIn256Bytes(charMask);\r |
135 | MASK(s->Symbol) = 0;\r |
136 | p->PrevSuccess = 0;\r |
137 | }\r |
138 | }\r |
139 | for (;;)\r |
140 | {\r |
141 | UInt32 escFreq;\r |
142 | CPpmd_See *see;\r |
143 | CPpmd_State *s;\r |
144 | UInt32 sum;\r |
145 | unsigned i, numMasked = p->MinContext->NumStats;\r |
146 | do\r |
147 | {\r |
148 | p->OrderFall++;\r |
149 | if (!p->MinContext->Suffix)\r |
150 | return; /* EndMarker (symbol = -1) */\r |
151 | p->MinContext = Ppmd7_GetContext(p, p->MinContext->Suffix);\r |
152 | }\r |
153 | while (p->MinContext->NumStats == numMasked);\r |
154 | \r |
155 | see = Ppmd7_MakeEscFreq(p, numMasked, &escFreq);\r |
156 | s = Ppmd7_GetStats(p, p->MinContext);\r |
157 | sum = 0;\r |
158 | i = p->MinContext->NumStats;\r |
159 | do\r |
160 | {\r |
161 | int cur = s->Symbol;\r |
162 | if (cur == symbol)\r |
163 | {\r |
164 | UInt32 low = sum;\r |
165 | CPpmd_State *s1 = s;\r |
166 | do\r |
167 | {\r |
168 | sum += (s->Freq & (int)(MASK(s->Symbol)));\r |
169 | s++;\r |
170 | }\r |
171 | while (--i);\r |
172 | RangeEnc_Encode(rc, low, s1->Freq, sum + escFreq);\r |
173 | Ppmd_See_Update(see);\r |
174 | p->FoundState = s1;\r |
175 | Ppmd7_Update2(p);\r |
176 | return;\r |
177 | }\r |
178 | sum += (s->Freq & (int)(MASK(cur)));\r |
179 | MASK(cur) = 0;\r |
180 | s++;\r |
181 | }\r |
182 | while (--i);\r |
183 | \r |
184 | RangeEnc_Encode(rc, sum, escFreq, sum + escFreq);\r |
185 | see->Summ = (UInt16)(see->Summ + sum + escFreq);\r |
186 | }\r |
187 | }\r |