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/* Copyright 2015 Google Inc. All Rights Reserved.
Distributed under MIT license.
See file LICENSE for detail or copy at
/* Algorithms for distributing the literals and commands of a metablock between
block types and contexts. */
#include "../common/platform.h"
#include <brotli/types.h>
#include "./block_splitter.h"
#include "./command.h"
#include "./context.h"
#include "./histogram.h"
#include "./memory.h"
#include "./quality.h"
#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
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) {
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. */
BROTLI_INTERNAL void BrotliBuildMetaBlock(MemoryManager* m,
const uint8_t* ringbuffer,
const size_t pos,
const size_t mask,
const BrotliEncoderParams* params,
uint8_t prev_byte,
uint8_t prev_byte2,
const 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, ContextType literal_context_mode,
size_t num_contexts, const uint32_t* static_context_map,
const Command* commands, size_t n_commands, MetaBlockSplit* mb);
BROTLI_INTERNAL void BrotliOptimizeHistograms(size_t num_direct_distance_codes,
size_t distance_postfix_bits,
MetaBlockSplit* mb);
#if defined(__cplusplus) || defined(c_plusplus)
} /* extern "C" */