| /* Copyright 2015 Google Inc. All Rights Reserved. |
| |
| Distributed under MIT license. |
| See file LICENSE for detail or copy at https://opensource.org/licenses/MIT |
| */ |
| |
| /* Algorithms for distributing the literals and commands of a metablock between |
| block types and contexts. */ |
| |
| #ifndef BROTLI_ENC_METABLOCK_H_ |
| #define BROTLI_ENC_METABLOCK_H_ |
| |
| #include "../common/context.h" |
| #include "../common/platform.h" |
| #include <brotli/types.h> |
| #include "./block_splitter.h" |
| #include "./command.h" |
| #include "./histogram.h" |
| #include "./memory.h" |
| #include "./quality.h" |
| |
| #if defined(__cplusplus) || defined(c_plusplus) |
| extern "C" { |
| #endif |
| |
| typedef struct MetaBlockSplit { |
| BlockSplit literal_split; |
| BlockSplit command_split; |
| BlockSplit distance_split; |
| uint32_t* literal_context_map; |
| size_t literal_context_map_size; |
| uint32_t* distance_context_map; |
| size_t distance_context_map_size; |
| HistogramLiteral* literal_histograms; |
| size_t literal_histograms_size; |
| HistogramCommand* command_histograms; |
| size_t command_histograms_size; |
| HistogramDistance* distance_histograms; |
| size_t distance_histograms_size; |
| } MetaBlockSplit; |
| |
| static BROTLI_INLINE void InitMetaBlockSplit(MetaBlockSplit* mb) { |
| BrotliInitBlockSplit(&mb->literal_split); |
| BrotliInitBlockSplit(&mb->command_split); |
| BrotliInitBlockSplit(&mb->distance_split); |
| mb->literal_context_map = 0; |
| mb->literal_context_map_size = 0; |
| mb->distance_context_map = 0; |
| mb->distance_context_map_size = 0; |
| mb->literal_histograms = 0; |
| mb->literal_histograms_size = 0; |
| mb->command_histograms = 0; |
| mb->command_histograms_size = 0; |
| mb->distance_histograms = 0; |
| mb->distance_histograms_size = 0; |
| } |
| |
| static BROTLI_INLINE void DestroyMetaBlockSplit( |
| MemoryManager* m, MetaBlockSplit* mb) { |
| BrotliDestroyBlockSplit(m, &mb->literal_split); |
| BrotliDestroyBlockSplit(m, &mb->command_split); |
| BrotliDestroyBlockSplit(m, &mb->distance_split); |
| BROTLI_FREE(m, mb->literal_context_map); |
| BROTLI_FREE(m, mb->distance_context_map); |
| BROTLI_FREE(m, mb->literal_histograms); |
| BROTLI_FREE(m, mb->command_histograms); |
| BROTLI_FREE(m, mb->distance_histograms); |
| } |
| |
| /* Uses the slow shortest-path block splitter and does context clustering. |
| The distance parameters are dynamically selected based on the commands |
| which get recomputed under the new distance parameters. The new distance |
| parameters are stored into *params. */ |
| BROTLI_INTERNAL void BrotliBuildMetaBlock(MemoryManager* m, |
| const uint8_t* ringbuffer, |
| const size_t pos, |
| const size_t mask, |
| BrotliEncoderParams* params, |
| uint8_t prev_byte, |
| uint8_t prev_byte2, |
| Command* cmds, |
| size_t num_commands, |
| ContextType literal_context_mode, |
| MetaBlockSplit* mb); |
| |
| /* Uses a fast greedy block splitter that tries to merge current block with the |
| last or the second last block and uses a static context clustering which |
| is the same for all block types. */ |
| BROTLI_INTERNAL void BrotliBuildMetaBlockGreedy( |
| MemoryManager* m, const uint8_t* ringbuffer, size_t pos, size_t mask, |
| uint8_t prev_byte, uint8_t prev_byte2, ContextLut literal_context_lut, |
| size_t num_contexts, const uint32_t* static_context_map, |
| const Command* commands, size_t n_commands, MetaBlockSplit* mb); |
| |
| BROTLI_INTERNAL void BrotliOptimizeHistograms(uint32_t num_distance_codes, |
| MetaBlockSplit* mb); |
| |
| BROTLI_INTERNAL void BrotliInitDistanceParams(BrotliEncoderParams* params, |
| uint32_t npostfix, uint32_t ndirect); |
| |
| #if defined(__cplusplus) || defined(c_plusplus) |
| } /* extern "C" */ |
| #endif |
| |
| #endif /* BROTLI_ENC_METABLOCK_H_ */ |