1 /* 2 Copyright 2011 Google Inc. All Rights Reserved. 3 4 Licensed under the Apache License, Version 2.0 (the "License"); 5 you may not use this file except in compliance with the License. 6 You may obtain a copy of the License at 7 8 http://www.apache.org/licenses/LICENSE-2.0 9 10 Unless required by applicable law or agreed to in writing, software 11 distributed under the License is distributed on an "AS IS" BASIS, 12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 See the License for the specific language governing permissions and 14 limitations under the License. 15 16 Author: lode.vandevenne (at) gmail.com (Lode Vandevenne) 17 Author: jyrki.alakuijala (at) gmail.com (Jyrki Alakuijala) 18 */ 19 20 #include "util.h" 21 22 #include "zopfli.h" 23 24 #include <assert.h> 25 #include <stdio.h> 26 #include <stdlib.h> 27 28 int ZopfliGetDistExtraBits(int dist) { 29 #ifdef __GNUC__ 30 if (dist < 5) return 0; 31 return (31 ^ __builtin_clz(dist - 1)) - 1; /* log2(dist - 1) - 1 */ 32 #else 33 if (dist < 5) return 0; 34 else if (dist < 9) return 1; 35 else if (dist < 17) return 2; 36 else if (dist < 33) return 3; 37 else if (dist < 65) return 4; 38 else if (dist < 129) return 5; 39 else if (dist < 257) return 6; 40 else if (dist < 513) return 7; 41 else if (dist < 1025) return 8; 42 else if (dist < 2049) return 9; 43 else if (dist < 4097) return 10; 44 else if (dist < 8193) return 11; 45 else if (dist < 16385) return 12; 46 else return 13; 47 #endif 48 } 49 50 int ZopfliGetDistExtraBitsValue(int dist) { 51 #ifdef __GNUC__ 52 if (dist < 5) { 53 return 0; 54 } else { 55 int l = 31 ^ __builtin_clz(dist - 1); /* log2(dist - 1) */ 56 return (dist - (1 + (1 << l))) & ((1 << (l - 1)) - 1); 57 } 58 #else 59 if (dist < 5) return 0; 60 else if (dist < 9) return (dist - 5) & 1; 61 else if (dist < 17) return (dist - 9) & 3; 62 else if (dist < 33) return (dist - 17) & 7; 63 else if (dist < 65) return (dist - 33) & 15; 64 else if (dist < 129) return (dist - 65) & 31; 65 else if (dist < 257) return (dist - 129) & 63; 66 else if (dist < 513) return (dist - 257) & 127; 67 else if (dist < 1025) return (dist - 513) & 255; 68 else if (dist < 2049) return (dist - 1025) & 511; 69 else if (dist < 4097) return (dist - 2049) & 1023; 70 else if (dist < 8193) return (dist - 4097) & 2047; 71 else if (dist < 16385) return (dist - 8193) & 4095; 72 else return (dist - 16385) & 8191; 73 #endif 74 } 75 76 int ZopfliGetDistSymbol(int dist) { 77 #ifdef __GNUC__ 78 if (dist < 5) { 79 return dist - 1; 80 } else { 81 int l = (31 ^ __builtin_clz(dist - 1)); /* log2(dist - 1) */ 82 int r = ((dist - 1) >> (l - 1)) & 1; 83 return l * 2 + r; 84 } 85 #else 86 if (dist < 193) { 87 if (dist < 13) { /* dist 0..13. */ 88 if (dist < 5) return dist - 1; 89 else if (dist < 7) return 4; 90 else if (dist < 9) return 5; 91 else return 6; 92 } else { /* dist 13..193. */ 93 if (dist < 17) return 7; 94 else if (dist < 25) return 8; 95 else if (dist < 33) return 9; 96 else if (dist < 49) return 10; 97 else if (dist < 65) return 11; 98 else if (dist < 97) return 12; 99 else if (dist < 129) return 13; 100 else return 14; 101 } 102 } else { 103 if (dist < 2049) { /* dist 193..2049. */ 104 if (dist < 257) return 15; 105 else if (dist < 385) return 16; 106 else if (dist < 513) return 17; 107 else if (dist < 769) return 18; 108 else if (dist < 1025) return 19; 109 else if (dist < 1537) return 20; 110 else return 21; 111 } else { /* dist 2049..32768. */ 112 if (dist < 3073) return 22; 113 else if (dist < 4097) return 23; 114 else if (dist < 6145) return 24; 115 else if (dist < 8193) return 25; 116 else if (dist < 12289) return 26; 117 else if (dist < 16385) return 27; 118 else if (dist < 24577) return 28; 119 else return 29; 120 } 121 } 122 #endif 123 } 124 125 int ZopfliGetLengthExtraBits(int l) { 126 static const int table[259] = { 127 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 128 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 129 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 130 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 131 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 132 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 133 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 134 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 135 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 136 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 137 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 138 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 139 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 140 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 141 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 142 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 0 143 }; 144 return table[l]; 145 } 146 147 int ZopfliGetLengthExtraBitsValue(int l) { 148 static const int table[259] = { 149 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 2, 3, 0, 150 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3, 4, 5, 6, 7, 0, 1, 2, 3, 4, 5, 151 6, 7, 0, 1, 2, 3, 4, 5, 6, 7, 0, 1, 2, 3, 4, 5, 6, 7, 0, 1, 2, 3, 4, 5, 6, 152 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 153 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 154 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 155 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 156 29, 30, 31, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 157 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 0, 1, 2, 3, 4, 5, 6, 158 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 159 27, 28, 29, 30, 31, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 160 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 0 161 }; 162 return table[l]; 163 } 164 165 /* 166 Returns symbol in range [257-285] (inclusive). 167 */ 168 int ZopfliGetLengthSymbol(int l) { 169 static const int table[259] = { 170 0, 0, 0, 257, 258, 259, 260, 261, 262, 263, 264, 171 265, 265, 266, 266, 267, 267, 268, 268, 172 269, 269, 269, 269, 270, 270, 270, 270, 173 271, 271, 271, 271, 272, 272, 272, 272, 174 273, 273, 273, 273, 273, 273, 273, 273, 175 274, 274, 274, 274, 274, 274, 274, 274, 176 275, 275, 275, 275, 275, 275, 275, 275, 177 276, 276, 276, 276, 276, 276, 276, 276, 178 277, 277, 277, 277, 277, 277, 277, 277, 179 277, 277, 277, 277, 277, 277, 277, 277, 180 278, 278, 278, 278, 278, 278, 278, 278, 181 278, 278, 278, 278, 278, 278, 278, 278, 182 279, 279, 279, 279, 279, 279, 279, 279, 183 279, 279, 279, 279, 279, 279, 279, 279, 184 280, 280, 280, 280, 280, 280, 280, 280, 185 280, 280, 280, 280, 280, 280, 280, 280, 186 281, 281, 281, 281, 281, 281, 281, 281, 187 281, 281, 281, 281, 281, 281, 281, 281, 188 281, 281, 281, 281, 281, 281, 281, 281, 189 281, 281, 281, 281, 281, 281, 281, 281, 190 282, 282, 282, 282, 282, 282, 282, 282, 191 282, 282, 282, 282, 282, 282, 282, 282, 192 282, 282, 282, 282, 282, 282, 282, 282, 193 282, 282, 282, 282, 282, 282, 282, 282, 194 283, 283, 283, 283, 283, 283, 283, 283, 195 283, 283, 283, 283, 283, 283, 283, 283, 196 283, 283, 283, 283, 283, 283, 283, 283, 197 283, 283, 283, 283, 283, 283, 283, 283, 198 284, 284, 284, 284, 284, 284, 284, 284, 199 284, 284, 284, 284, 284, 284, 284, 284, 200 284, 284, 284, 284, 284, 284, 284, 284, 201 284, 284, 284, 284, 284, 284, 284, 285 202 }; 203 return table[l]; 204 } 205 206 void ZopfliInitOptions(ZopfliOptions* options) { 207 options->verbose = 0; 208 options->verbose_more = 0; 209 options->numiterations = 15; 210 options->blocksplitting = 1; 211 options->blocksplittinglast = 0; 212 options->blocksplittingmax = 15; 213 } 214
