diff options
Diffstat (limited to 'dviware/dvisvgm/libs/brotli/enc/quality.h')
-rw-r--r-- | dviware/dvisvgm/libs/brotli/enc/quality.h | 43 |
1 files changed, 40 insertions, 3 deletions
diff --git a/dviware/dvisvgm/libs/brotli/enc/quality.h b/dviware/dvisvgm/libs/brotli/enc/quality.h index 5f4d034503..ffdfd72fb4 100644 --- a/dviware/dvisvgm/libs/brotli/enc/quality.h +++ b/dviware/dvisvgm/libs/brotli/enc/quality.h @@ -10,9 +10,10 @@ #ifndef BROTLI_ENC_QUALITY_H_ #define BROTLI_ENC_QUALITY_H_ -#include "../common/platform.h" #include <brotli/encode.h> -#include "./params.h" + +#include "../common/platform.h" +#include "params.h" #define FAST_ONE_PASS_COMPRESSION_QUALITY 0 #define FAST_TWO_PASS_COMPRESSION_QUALITY 1 @@ -118,6 +119,41 @@ static BROTLI_INLINE size_t LiteralSpreeLengthForSparseSearch( return params->quality < 9 ? 64 : 512; } +/* Quality to hasher mapping: + + - q02: h02 (longest_match_quickly), b16, l5 + + - q03: h03 (longest_match_quickly), b17, l5 + + - q04: h04 (longest_match_quickly), b17, l5 + - q04: h54 (longest_match_quickly), b20, l7 | for large files + + - q05: h05 (longest_match ), b14, l4 + - q05: h06 (longest_match64 ), b15, l5 | for large files + - q05: h40 (forgetful_chain ), b15, l4 | for small window + + - q06: h05 (longest_match ), b14, l4 + - q06: h06 (longest_match64 ), b15, l5 | for large files + - q06: h40 (forgetful_chain ), b15, l4 | for small window + + - q07: h05 (longest_match ), b15, l4 + - q07: h06 (longest_match64 ), b15, l5 | for large files + - q07: h41 (forgetful_chain ), b15, l4 | for small window + + - q08: h05 (longest_match ), b15, l4 + - q08: h06 (longest_match64 ), b15, l5 | for large files + - q08: h41 (forgetful_chain ), b15, l4 | for small window + + - q09: h05 (longest_match ), b15, l4 + - q09: h06 (longest_match64 ), b15, l5 | for large files + - q09: h42 (forgetful_chain ), b15, l4 | for small window + + - q10: t10 (to_binary_tree ), b17, l128 + + - q11: t10 (to_binary_tree ), b17, l128 + + Where "q" is quality, "h" is hasher type, "b" is bucket bits, + "l" is source len. */ static BROTLI_INLINE void ChooseHasher(const BrotliEncoderParams* params, BrotliHasherParams* hparams) { if (params->quality > 9) { @@ -132,10 +168,11 @@ static BROTLI_INLINE void ChooseHasher(const BrotliEncoderParams* params, hparams->type = 6; hparams->block_bits = params->quality - 1; hparams->bucket_bits = 15; - hparams->hash_len = 5; hparams->num_last_distances_to_check = params->quality < 7 ? 4 : params->quality < 9 ? 10 : 16; } else { + /* TODO(eustas): often previous setting (H6) is faster and denser; consider + adding an option to use it. */ hparams->type = 5; hparams->block_bits = params->quality - 1; hparams->bucket_bits = params->quality < 7 ? 14 : 15; |