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MdeModulePkg/BrotliCustomDecompressLib: Make brotli a submodule
[mirror_edk2.git] / BaseTools / Source / C / BrotliCompress / enc / quality.h
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1/* Copyright 2016 Google Inc. All Rights Reserved.\r
2\r
3 Distributed under MIT license.\r
4 See file LICENSE for detail or copy at https://opensource.org/licenses/MIT\r
5*/\r
6\r
7/* Constants and formulas that affect speed-ratio trade-offs and thus define\r
8 quality levels. */\r
9\r
10#ifndef BROTLI_ENC_QUALITY_H_\r
11#define BROTLI_ENC_QUALITY_H_\r
12\r
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13#include "../common/platform.h"\r
14#include <brotli/encode.h>\r
15#include "./params.h"\r
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16\r
17#define FAST_ONE_PASS_COMPRESSION_QUALITY 0\r
18#define FAST_TWO_PASS_COMPRESSION_QUALITY 1\r
19#define ZOPFLIFICATION_QUALITY 10\r
20#define HQ_ZOPFLIFICATION_QUALITY 11\r
21\r
dd4f667e 22#define MAX_QUALITY_FOR_STATIC_ENTROPY_CODES 2\r
11b7501a 23#define MIN_QUALITY_FOR_BLOCK_SPLIT 4\r
dd4f667e 24#define MIN_QUALITY_FOR_NONZERO_DISTANCE_PARAMS 4\r
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25#define MIN_QUALITY_FOR_OPTIMIZE_HISTOGRAMS 4\r
26#define MIN_QUALITY_FOR_EXTENSIVE_REFERENCE_SEARCH 5\r
27#define MIN_QUALITY_FOR_CONTEXT_MODELING 5\r
28#define MIN_QUALITY_FOR_HQ_CONTEXT_MODELING 7\r
29#define MIN_QUALITY_FOR_HQ_BLOCK_SPLITTING 10\r
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30\r
31/* For quality below MIN_QUALITY_FOR_BLOCK_SPLIT there is no block splitting,\r
32 so we buffer at most this much literals and commands. */\r
dd4f667e 33#define MAX_NUM_DELAYED_SYMBOLS 0x2FFF\r
11b7501a 34\r
dd4f667e 35/* Returns hash-table size for quality levels 0 and 1. */\r
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36static BROTLI_INLINE size_t MaxHashTableSize(int quality) {\r
37 return quality == FAST_ONE_PASS_COMPRESSION_QUALITY ? 1 << 15 : 1 << 17;\r
38}\r
39\r
40/* The maximum length for which the zopflification uses distinct distances. */\r
41#define MAX_ZOPFLI_LEN_QUALITY_10 150\r
42#define MAX_ZOPFLI_LEN_QUALITY_11 325\r
43\r
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44/* Do not thoroughly search when a long copy is found. */\r
45#define BROTLI_LONG_COPY_QUICK_STEP 16384\r
46\r
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47static BROTLI_INLINE size_t MaxZopfliLen(const BrotliEncoderParams* params) {\r
48 return params->quality <= 10 ?\r
49 MAX_ZOPFLI_LEN_QUALITY_10 :\r
50 MAX_ZOPFLI_LEN_QUALITY_11;\r
51}\r
52\r
dd4f667e 53/* Number of best candidates to evaluate to expand Zopfli chain. */\r
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54static BROTLI_INLINE size_t MaxZopfliCandidates(\r
55 const BrotliEncoderParams* params) {\r
56 return params->quality <= 10 ? 1 : 5;\r
57}\r
58\r
59static BROTLI_INLINE void SanitizeParams(BrotliEncoderParams* params) {\r
60 params->quality = BROTLI_MIN(int, BROTLI_MAX_QUALITY,\r
61 BROTLI_MAX(int, BROTLI_MIN_QUALITY, params->quality));\r
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62 if (params->quality <= MAX_QUALITY_FOR_STATIC_ENTROPY_CODES) {\r
63 params->large_window = BROTLI_FALSE;\r
64 }\r
65 if (params->lgwin < BROTLI_MIN_WINDOW_BITS) {\r
66 params->lgwin = BROTLI_MIN_WINDOW_BITS;\r
67 } else {\r
68 int max_lgwin = params->large_window ? BROTLI_LARGE_MAX_WINDOW_BITS :\r
69 BROTLI_MAX_WINDOW_BITS;\r
70 if (params->lgwin > max_lgwin) params->lgwin = max_lgwin;\r
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71 }\r
72}\r
73\r
74/* Returns optimized lg_block value. */\r
75static BROTLI_INLINE int ComputeLgBlock(const BrotliEncoderParams* params) {\r
76 int lgblock = params->lgblock;\r
77 if (params->quality == FAST_ONE_PASS_COMPRESSION_QUALITY ||\r
78 params->quality == FAST_TWO_PASS_COMPRESSION_QUALITY) {\r
79 lgblock = params->lgwin;\r
80 } else if (params->quality < MIN_QUALITY_FOR_BLOCK_SPLIT) {\r
81 lgblock = 14;\r
82 } else if (lgblock == 0) {\r
83 lgblock = 16;\r
84 if (params->quality >= 9 && params->lgwin > lgblock) {\r
85 lgblock = BROTLI_MIN(int, 18, params->lgwin);\r
86 }\r
87 } else {\r
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88 lgblock = BROTLI_MIN(int, BROTLI_MAX_INPUT_BLOCK_BITS,\r
89 BROTLI_MAX(int, BROTLI_MIN_INPUT_BLOCK_BITS, lgblock));\r
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90 }\r
91 return lgblock;\r
92}\r
93\r
94/* Returns log2 of the size of main ring buffer area.\r
95 Allocate at least lgwin + 1 bits for the ring buffer so that the newly\r
96 added block fits there completely and we still get lgwin bits and at least\r
97 read_block_size_bits + 1 bits because the copy tail length needs to be\r
dd4f667e 98 smaller than ring-buffer size. */\r
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99static BROTLI_INLINE int ComputeRbBits(const BrotliEncoderParams* params) {\r
100 return 1 + BROTLI_MAX(int, params->lgwin, params->lgblock);\r
101}\r
102\r
103static BROTLI_INLINE size_t MaxMetablockSize(\r
104 const BrotliEncoderParams* params) {\r
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105 int bits =\r
106 BROTLI_MIN(int, ComputeRbBits(params), BROTLI_MAX_INPUT_BLOCK_BITS);\r
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107 return (size_t)1 << bits;\r
108}\r
109\r
110/* When searching for backward references and have not seen matches for a long\r
111 time, we can skip some match lookups. Unsuccessful match lookups are very\r
112 expensive and this kind of a heuristic speeds up compression quite a lot.\r
113 At first 8 byte strides are taken and every second byte is put to hasher.\r
114 After 4x more literals stride by 16 bytes, every put 4-th byte to hasher.\r
115 Applied only to qualities 2 to 9. */\r
116static BROTLI_INLINE size_t LiteralSpreeLengthForSparseSearch(\r
117 const BrotliEncoderParams* params) {\r
118 return params->quality < 9 ? 64 : 512;\r
119}\r
120\r
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121static BROTLI_INLINE void ChooseHasher(const BrotliEncoderParams* params,\r
122 BrotliHasherParams* hparams) {\r
11b7501a 123 if (params->quality > 9) {\r
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124 hparams->type = 10;\r
125 } else if (params->quality == 4 && params->size_hint >= (1 << 20)) {\r
126 hparams->type = 54;\r
11b7501a 127 } else if (params->quality < 5) {\r
dd4f667e 128 hparams->type = params->quality;\r
11b7501a 129 } else if (params->lgwin <= 16) {\r
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130 hparams->type = params->quality < 7 ? 40 : params->quality < 9 ? 41 : 42;\r
131 } else if (params->size_hint >= (1 << 20) && params->lgwin >= 19) {\r
132 hparams->type = 6;\r
133 hparams->block_bits = params->quality - 1;\r
134 hparams->bucket_bits = 15;\r
135 hparams->hash_len = 5;\r
136 hparams->num_last_distances_to_check =\r
137 params->quality < 7 ? 4 : params->quality < 9 ? 10 : 16;\r
138 } else {\r
139 hparams->type = 5;\r
140 hparams->block_bits = params->quality - 1;\r
141 hparams->bucket_bits = params->quality < 7 ? 14 : 15;\r
142 hparams->num_last_distances_to_check =\r
143 params->quality < 7 ? 4 : params->quality < 9 ? 10 : 16;\r
144 }\r
145\r
146 if (params->lgwin > 24) {\r
147 /* Different hashers for large window brotli: not for qualities <= 2,\r
148 these are too fast for large window. Not for qualities >= 10: their\r
149 hasher already works well with large window. So the changes are:\r
150 H3 --> H35: for quality 3.\r
151 H54 --> H55: for quality 4 with size hint > 1MB\r
152 H6 --> H65: for qualities 5, 6, 7, 8, 9. */\r
153 if (hparams->type == 3) {\r
154 hparams->type = 35;\r
155 }\r
156 if (hparams->type == 54) {\r
157 hparams->type = 55;\r
158 }\r
159 if (hparams->type == 6) {\r
160 hparams->type = 65;\r
161 }\r
11b7501a 162 }\r
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163}\r
164\r
165#endif /* BROTLI_ENC_QUALITY_H_ */\r