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-rw-r--r--src/zopfli/symbols.h239
1 files changed, 0 insertions, 239 deletions
diff --git a/src/zopfli/symbols.h b/src/zopfli/symbols.h
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--- a/src/zopfli/symbols.h
+++ /dev/null
@@ -1,239 +0,0 @@
-/*
-Copyright 2016 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
- http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-
-Author: lode.vandevenne@gmail.com (Lode Vandevenne)
-Author: jyrki.alakuijala@gmail.com (Jyrki Alakuijala)
-*/
-
-/*
-Utilities for using the lz77 symbols of the deflate spec.
-*/
-
-#ifndef ZOPFLI_SYMBOLS_H_
-#define ZOPFLI_SYMBOLS_H_
-
-/* __has_builtin available in clang */
-#ifdef __has_builtin
-# if __has_builtin(__builtin_clz)
-# define ZOPFLI_HAS_BUILTIN_CLZ
-# endif
-/* __builtin_clz available beginning with GCC 3.4 */
-#elif __GNUC__ * 100 + __GNUC_MINOR__ >= 304
-# define ZOPFLI_HAS_BUILTIN_CLZ
-#endif
-
-/* Gets the amount of extra bits for the given dist, cfr. the DEFLATE spec. */
-static int ZopfliGetDistExtraBits(int dist) {
-#ifdef ZOPFLI_HAS_BUILTIN_CLZ
- if (dist < 5) return 0;
- return (31 ^ __builtin_clz(dist - 1)) - 1; /* log2(dist - 1) - 1 */
-#else
- if (dist < 5) return 0;
- else if (dist < 9) return 1;
- else if (dist < 17) return 2;
- else if (dist < 33) return 3;
- else if (dist < 65) return 4;
- else if (dist < 129) return 5;
- else if (dist < 257) return 6;
- else if (dist < 513) return 7;
- else if (dist < 1025) return 8;
- else if (dist < 2049) return 9;
- else if (dist < 4097) return 10;
- else if (dist < 8193) return 11;
- else if (dist < 16385) return 12;
- else return 13;
-#endif
-}
-
-/* Gets value of the extra bits for the given dist, cfr. the DEFLATE spec. */
-static int ZopfliGetDistExtraBitsValue(int dist) {
-#ifdef ZOPFLI_HAS_BUILTIN_CLZ
- if (dist < 5) {
- return 0;
- } else {
- int l = 31 ^ __builtin_clz(dist - 1); /* log2(dist - 1) */
- return (dist - (1 + (1 << l))) & ((1 << (l - 1)) - 1);
- }
-#else
- if (dist < 5) return 0;
- else if (dist < 9) return (dist - 5) & 1;
- else if (dist < 17) return (dist - 9) & 3;
- else if (dist < 33) return (dist - 17) & 7;
- else if (dist < 65) return (dist - 33) & 15;
- else if (dist < 129) return (dist - 65) & 31;
- else if (dist < 257) return (dist - 129) & 63;
- else if (dist < 513) return (dist - 257) & 127;
- else if (dist < 1025) return (dist - 513) & 255;
- else if (dist < 2049) return (dist - 1025) & 511;
- else if (dist < 4097) return (dist - 2049) & 1023;
- else if (dist < 8193) return (dist - 4097) & 2047;
- else if (dist < 16385) return (dist - 8193) & 4095;
- else return (dist - 16385) & 8191;
-#endif
-}
-
-/* Gets the symbol for the given dist, cfr. the DEFLATE spec. */
-static int ZopfliGetDistSymbol(int dist) {
-#ifdef ZOPFLI_HAS_BUILTIN_CLZ
- if (dist < 5) {
- return dist - 1;
- } else {
- int l = (31 ^ __builtin_clz(dist - 1)); /* log2(dist - 1) */
- int r = ((dist - 1) >> (l - 1)) & 1;
- return l * 2 + r;
- }
-#else
- if (dist < 193) {
- if (dist < 13) { /* dist 0..13. */
- if (dist < 5) return dist - 1;
- else if (dist < 7) return 4;
- else if (dist < 9) return 5;
- else return 6;
- } else { /* dist 13..193. */
- if (dist < 17) return 7;
- else if (dist < 25) return 8;
- else if (dist < 33) return 9;
- else if (dist < 49) return 10;
- else if (dist < 65) return 11;
- else if (dist < 97) return 12;
- else if (dist < 129) return 13;
- else return 14;
- }
- } else {
- if (dist < 2049) { /* dist 193..2049. */
- if (dist < 257) return 15;
- else if (dist < 385) return 16;
- else if (dist < 513) return 17;
- else if (dist < 769) return 18;
- else if (dist < 1025) return 19;
- else if (dist < 1537) return 20;
- else return 21;
- } else { /* dist 2049..32768. */
- if (dist < 3073) return 22;
- else if (dist < 4097) return 23;
- else if (dist < 6145) return 24;
- else if (dist < 8193) return 25;
- else if (dist < 12289) return 26;
- else if (dist < 16385) return 27;
- else if (dist < 24577) return 28;
- else return 29;
- }
- }
-#endif
-}
-
-/* Gets the amount of extra bits for the given length, cfr. the DEFLATE spec. */
-static int ZopfliGetLengthExtraBits(int l) {
- static const int table[259] = {
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1,
- 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
- 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
- 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
- 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
- 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
- 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
- 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
- 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
- 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
- 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
- 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
- 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
- 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
- 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
- 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 0
- };
- return table[l];
-}
-
-/* Gets value of the extra bits for the given length, cfr. the DEFLATE spec. */
-static int ZopfliGetLengthExtraBitsValue(int l) {
- static const int table[259] = {
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 2, 3, 0,
- 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,
- 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,
- 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,
- 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2,
- 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
- 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28,
- 29, 30, 31, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
- 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 0, 1, 2, 3, 4, 5, 6,
- 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,
- 27, 28, 29, 30, 31, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
- 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 0
- };
- return table[l];
-}
-
-/*
-Gets the symbol for the given length, cfr. the DEFLATE spec.
-Returns the symbol in the range [257-285] (inclusive)
-*/
-static int ZopfliGetLengthSymbol(int l) {
- static const int table[259] = {
- 0, 0, 0, 257, 258, 259, 260, 261, 262, 263, 264,
- 265, 265, 266, 266, 267, 267, 268, 268,
- 269, 269, 269, 269, 270, 270, 270, 270,
- 271, 271, 271, 271, 272, 272, 272, 272,
- 273, 273, 273, 273, 273, 273, 273, 273,
- 274, 274, 274, 274, 274, 274, 274, 274,
- 275, 275, 275, 275, 275, 275, 275, 275,
- 276, 276, 276, 276, 276, 276, 276, 276,
- 277, 277, 277, 277, 277, 277, 277, 277,
- 277, 277, 277, 277, 277, 277, 277, 277,
- 278, 278, 278, 278, 278, 278, 278, 278,
- 278, 278, 278, 278, 278, 278, 278, 278,
- 279, 279, 279, 279, 279, 279, 279, 279,
- 279, 279, 279, 279, 279, 279, 279, 279,
- 280, 280, 280, 280, 280, 280, 280, 280,
- 280, 280, 280, 280, 280, 280, 280, 280,
- 281, 281, 281, 281, 281, 281, 281, 281,
- 281, 281, 281, 281, 281, 281, 281, 281,
- 281, 281, 281, 281, 281, 281, 281, 281,
- 281, 281, 281, 281, 281, 281, 281, 281,
- 282, 282, 282, 282, 282, 282, 282, 282,
- 282, 282, 282, 282, 282, 282, 282, 282,
- 282, 282, 282, 282, 282, 282, 282, 282,
- 282, 282, 282, 282, 282, 282, 282, 282,
- 283, 283, 283, 283, 283, 283, 283, 283,
- 283, 283, 283, 283, 283, 283, 283, 283,
- 283, 283, 283, 283, 283, 283, 283, 283,
- 283, 283, 283, 283, 283, 283, 283, 283,
- 284, 284, 284, 284, 284, 284, 284, 284,
- 284, 284, 284, 284, 284, 284, 284, 284,
- 284, 284, 284, 284, 284, 284, 284, 284,
- 284, 284, 284, 284, 284, 284, 284, 285
- };
- return table[l];
-}
-
-/* Gets the amount of extra bits for the given length symbol. */
-static int ZopfliGetLengthSymbolExtraBits(int s) {
- static const int table[29] = {
- 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
- 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0
- };
- return table[s - 257];
-}
-
-/* Gets the amount of extra bits for the given distance symbol. */
-static int ZopfliGetDistSymbolExtraBits(int s) {
- static const int table[30] = {
- 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8,
- 9, 9, 10, 10, 11, 11, 12, 12, 13, 13
- };
- return table[s];
-}
-
-#endif /* ZOPFLI_SYMBOLS_H_ */
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-26 18:29:04 +0000