Index: third_party/brotli/enc/metablock.c |
diff --git a/third_party/brotli/enc/metablock.c b/third_party/brotli/enc/metablock.c |
new file mode 100644 |
index 0000000000000000000000000000000000000000..402aef6c1648ec4cccedf27abdffdc806cfabfd7 |
--- /dev/null |
+++ b/third_party/brotli/enc/metablock.c |
@@ -0,0 +1,516 @@ |
+/* 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. */ |
+ |
+#include "./metablock.h" |
+ |
+#include "../common/constants.h" |
+#include <brotli/types.h> |
+#include "./bit_cost.h" |
+#include "./block_splitter.h" |
+#include "./cluster.h" |
+#include "./context.h" |
+#include "./entropy_encode.h" |
+#include "./histogram.h" |
+#include "./memory.h" |
+#include "./port.h" |
+#include "./quality.h" |
+ |
+#if defined(__cplusplus) || defined(c_plusplus) |
+extern "C" { |
+#endif |
+ |
+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) { |
+ /* Histogram ids need to fit in one byte. */ |
+ static const size_t kMaxNumberOfHistograms = 256; |
+ HistogramDistance* distance_histograms; |
+ HistogramLiteral* literal_histograms; |
+ ContextType* literal_context_modes; |
+ size_t num_literal_contexts; |
+ size_t num_distance_contexts; |
+ size_t i; |
+ |
+ BrotliSplitBlock(m, cmds, num_commands, |
+ ringbuffer, pos, mask, params, |
+ &mb->literal_split, |
+ &mb->command_split, |
+ &mb->distance_split); |
+ if (BROTLI_IS_OOM(m)) return; |
+ |
+ literal_context_modes = |
+ BROTLI_ALLOC(m, ContextType, mb->literal_split.num_types); |
+ if (BROTLI_IS_OOM(m)) return; |
+ for (i = 0; i < mb->literal_split.num_types; ++i) { |
+ literal_context_modes[i] = literal_context_mode; |
+ } |
+ |
+ num_literal_contexts = |
+ mb->literal_split.num_types << BROTLI_LITERAL_CONTEXT_BITS; |
+ num_distance_contexts = |
+ mb->distance_split.num_types << BROTLI_DISTANCE_CONTEXT_BITS; |
+ literal_histograms = BROTLI_ALLOC(m, HistogramLiteral, num_literal_contexts); |
+ if (BROTLI_IS_OOM(m)) return; |
+ ClearHistogramsLiteral(literal_histograms, num_literal_contexts); |
+ |
+ assert(mb->command_histograms == 0); |
+ mb->command_histograms_size = mb->command_split.num_types; |
+ mb->command_histograms = |
+ BROTLI_ALLOC(m, HistogramCommand, mb->command_histograms_size); |
+ if (BROTLI_IS_OOM(m)) return; |
+ ClearHistogramsCommand(mb->command_histograms, mb->command_histograms_size); |
+ distance_histograms = |
+ BROTLI_ALLOC(m, HistogramDistance, num_distance_contexts); |
+ if (BROTLI_IS_OOM(m)) return; |
+ ClearHistogramsDistance(distance_histograms, num_distance_contexts); |
+ BrotliBuildHistogramsWithContext(cmds, num_commands, |
+ &mb->literal_split, &mb->command_split, &mb->distance_split, |
+ ringbuffer, pos, mask, prev_byte, prev_byte2, literal_context_modes, |
+ literal_histograms, mb->command_histograms, distance_histograms); |
+ BROTLI_FREE(m, literal_context_modes); |
+ |
+ assert(mb->literal_context_map == 0); |
+ mb->literal_context_map_size = |
+ mb->literal_split.num_types << BROTLI_LITERAL_CONTEXT_BITS; |
+ mb->literal_context_map = |
+ BROTLI_ALLOC(m, uint32_t, mb->literal_context_map_size); |
+ if (BROTLI_IS_OOM(m)) return; |
+ assert(mb->literal_histograms == 0); |
+ mb->literal_histograms_size = mb->literal_context_map_size; |
+ mb->literal_histograms = |
+ BROTLI_ALLOC(m, HistogramLiteral, mb->literal_histograms_size); |
+ if (BROTLI_IS_OOM(m)) return; |
+ BrotliClusterHistogramsLiteral(m, literal_histograms, |
+ mb->literal_context_map_size, |
+ kMaxNumberOfHistograms, |
+ mb->literal_histograms, |
+ &mb->literal_histograms_size, |
+ mb->literal_context_map); |
+ if (BROTLI_IS_OOM(m)) return; |
+ BROTLI_FREE(m, literal_histograms); |
+ |
+ assert(mb->distance_context_map == 0); |
+ mb->distance_context_map_size = |
+ mb->distance_split.num_types << BROTLI_DISTANCE_CONTEXT_BITS; |
+ mb->distance_context_map = |
+ BROTLI_ALLOC(m, uint32_t, mb->distance_context_map_size); |
+ if (BROTLI_IS_OOM(m)) return; |
+ assert(mb->distance_histograms == 0); |
+ mb->distance_histograms_size = mb->distance_context_map_size; |
+ mb->distance_histograms = |
+ BROTLI_ALLOC(m, HistogramDistance, mb->distance_histograms_size); |
+ if (BROTLI_IS_OOM(m)) return; |
+ BrotliClusterHistogramsDistance(m, distance_histograms, |
+ mb->distance_context_map_size, |
+ kMaxNumberOfHistograms, |
+ mb->distance_histograms, |
+ &mb->distance_histograms_size, |
+ mb->distance_context_map); |
+ if (BROTLI_IS_OOM(m)) return; |
+ BROTLI_FREE(m, distance_histograms); |
+} |
+ |
+#define FN(X) X ## Literal |
+#include "./metablock_inc.h" /* NOLINT(build/include) */ |
+#undef FN |
+ |
+#define FN(X) X ## Command |
+#include "./metablock_inc.h" /* NOLINT(build/include) */ |
+#undef FN |
+ |
+#define FN(X) X ## Distance |
+#include "./metablock_inc.h" /* NOLINT(build/include) */ |
+#undef FN |
+ |
+void BrotliBuildMetaBlockGreedy(MemoryManager* m, |
+ const uint8_t* ringbuffer, |
+ size_t pos, |
+ size_t mask, |
+ const Command *commands, |
+ size_t n_commands, |
+ MetaBlockSplit* mb) { |
+ BlockSplitterLiteral lit_blocks; |
+ BlockSplitterCommand cmd_blocks; |
+ BlockSplitterDistance dist_blocks; |
+ size_t num_literals = 0; |
+ size_t i; |
+ for (i = 0; i < n_commands; ++i) { |
+ num_literals += commands[i].insert_len_; |
+ } |
+ |
+ InitBlockSplitterLiteral(m, &lit_blocks, 256, 512, 400.0, num_literals, |
+ &mb->literal_split, &mb->literal_histograms, |
+ &mb->literal_histograms_size); |
+ if (BROTLI_IS_OOM(m)) return; |
+ InitBlockSplitterCommand(m, &cmd_blocks, BROTLI_NUM_COMMAND_SYMBOLS, 1024, |
+ 500.0, n_commands, &mb->command_split, &mb->command_histograms, |
+ &mb->command_histograms_size); |
+ if (BROTLI_IS_OOM(m)) return; |
+ InitBlockSplitterDistance(m, &dist_blocks, 64, 512, 100.0, n_commands, |
+ &mb->distance_split, &mb->distance_histograms, |
+ &mb->distance_histograms_size); |
+ if (BROTLI_IS_OOM(m)) return; |
+ |
+ for (i = 0; i < n_commands; ++i) { |
+ const Command cmd = commands[i]; |
+ size_t j; |
+ BlockSplitterAddSymbolCommand(&cmd_blocks, cmd.cmd_prefix_); |
+ for (j = cmd.insert_len_; j != 0; --j) { |
+ BlockSplitterAddSymbolLiteral(&lit_blocks, ringbuffer[pos & mask]); |
+ ++pos; |
+ } |
+ pos += CommandCopyLen(&cmd); |
+ if (CommandCopyLen(&cmd) && cmd.cmd_prefix_ >= 128) { |
+ BlockSplitterAddSymbolDistance(&dist_blocks, cmd.dist_prefix_); |
+ } |
+ } |
+ |
+ BlockSplitterFinishBlockLiteral(&lit_blocks, /* is_final = */ BROTLI_TRUE); |
+ BlockSplitterFinishBlockCommand(&cmd_blocks, /* is_final = */ BROTLI_TRUE); |
+ BlockSplitterFinishBlockDistance(&dist_blocks, /* is_final = */ BROTLI_TRUE); |
+} |
+ |
+/* Greedy block splitter for one block category (literal, command or distance). |
+ Gathers histograms for all context buckets. */ |
+typedef struct ContextBlockSplitter { |
+ /* Alphabet size of particular block category. */ |
+ size_t alphabet_size_; |
+ size_t num_contexts_; |
+ size_t max_block_types_; |
+ /* We collect at least this many symbols for each block. */ |
+ size_t min_block_size_; |
+ /* We merge histograms A and B if |
+ entropy(A+B) < entropy(A) + entropy(B) + split_threshold_, |
+ where A is the current histogram and B is the histogram of the last or the |
+ second last block type. */ |
+ double split_threshold_; |
+ |
+ size_t num_blocks_; |
+ BlockSplit* split_; /* not owned */ |
+ HistogramLiteral* histograms_; /* not owned */ |
+ size_t* histograms_size_; /* not owned */ |
+ |
+ /* The number of symbols that we want to collect before deciding on whether |
+ or not to merge the block with a previous one or emit a new block. */ |
+ size_t target_block_size_; |
+ /* The number of symbols in the current histogram. */ |
+ size_t block_size_; |
+ /* Offset of the current histogram. */ |
+ size_t curr_histogram_ix_; |
+ /* Offset of the histograms of the previous two block types. */ |
+ size_t last_histogram_ix_[2]; |
+ /* Entropy of the previous two block types. */ |
+ double* last_entropy_; |
+ /* The number of times we merged the current block with the last one. */ |
+ size_t merge_last_count_; |
+} ContextBlockSplitter; |
+ |
+static void InitContextBlockSplitter( |
+ MemoryManager* m, ContextBlockSplitter* self, size_t alphabet_size, |
+ size_t num_contexts, size_t min_block_size, double split_threshold, |
+ size_t num_symbols, BlockSplit* split, HistogramLiteral** histograms, |
+ size_t* histograms_size) { |
+ size_t max_num_blocks = num_symbols / min_block_size + 1; |
+ size_t max_num_types; |
+ |
+ self->alphabet_size_ = alphabet_size; |
+ self->num_contexts_ = num_contexts; |
+ self->max_block_types_ = BROTLI_MAX_NUMBER_OF_BLOCK_TYPES / num_contexts; |
+ self->min_block_size_ = min_block_size; |
+ self->split_threshold_ = split_threshold; |
+ self->num_blocks_ = 0; |
+ self->split_ = split; |
+ self->histograms_size_ = histograms_size; |
+ self->target_block_size_ = min_block_size; |
+ self->block_size_ = 0; |
+ self->curr_histogram_ix_ = 0; |
+ self->merge_last_count_ = 0; |
+ |
+ /* We have to allocate one more histogram than the maximum number of block |
+ types for the current histogram when the meta-block is too big. */ |
+ max_num_types = |
+ BROTLI_MIN(size_t, max_num_blocks, self->max_block_types_ + 1); |
+ BROTLI_ENSURE_CAPACITY(m, uint8_t, |
+ split->types, split->types_alloc_size, max_num_blocks); |
+ BROTLI_ENSURE_CAPACITY(m, uint32_t, |
+ split->lengths, split->lengths_alloc_size, max_num_blocks); |
+ if (BROTLI_IS_OOM(m)) return; |
+ split->num_blocks = max_num_blocks; |
+ self->last_entropy_ = BROTLI_ALLOC(m, double, 2 * num_contexts); |
+ if (BROTLI_IS_OOM(m)) return; |
+ assert(*histograms == 0); |
+ *histograms_size = max_num_types * num_contexts; |
+ *histograms = BROTLI_ALLOC(m, HistogramLiteral, *histograms_size); |
+ self->histograms_ = *histograms; |
+ if (BROTLI_IS_OOM(m)) return; |
+ /* Clear only current histogram. */ |
+ ClearHistogramsLiteral(&self->histograms_[0], num_contexts); |
+ self->last_histogram_ix_[0] = self->last_histogram_ix_[1] = 0; |
+} |
+ |
+static void CleanupContextBlockSplitter( |
+ MemoryManager* m, ContextBlockSplitter* self) { |
+ BROTLI_FREE(m, self->last_entropy_); |
+} |
+ |
+/* Does either of three things: |
+ (1) emits the current block with a new block type; |
+ (2) emits the current block with the type of the second last block; |
+ (3) merges the current block with the last block. */ |
+static void ContextBlockSplitterFinishBlock( |
+ MemoryManager* m, ContextBlockSplitter* self, BROTLI_BOOL is_final) { |
+ BlockSplit* split = self->split_; |
+ const size_t num_contexts = self->num_contexts_; |
+ double* last_entropy = self->last_entropy_; |
+ HistogramLiteral* histograms = self->histograms_; |
+ |
+ if (self->block_size_ < self->min_block_size_) { |
+ self->block_size_ = self->min_block_size_; |
+ } |
+ if (self->num_blocks_ == 0) { |
+ size_t i; |
+ /* Create first block. */ |
+ split->lengths[0] = (uint32_t)self->block_size_; |
+ split->types[0] = 0; |
+ |
+ for (i = 0; i < num_contexts; ++i) { |
+ last_entropy[i] = |
+ BitsEntropy(histograms[i].data_, self->alphabet_size_); |
+ last_entropy[num_contexts + i] = last_entropy[i]; |
+ } |
+ ++self->num_blocks_; |
+ ++split->num_types; |
+ self->curr_histogram_ix_ += num_contexts; |
+ if (self->curr_histogram_ix_ < *self->histograms_size_) { |
+ ClearHistogramsLiteral( |
+ &self->histograms_[self->curr_histogram_ix_], self->num_contexts_); |
+ } |
+ self->block_size_ = 0; |
+ } else if (self->block_size_ > 0) { |
+ /* Try merging the set of histograms for the current block type with the |
+ respective set of histograms for the last and second last block types. |
+ Decide over the split based on the total reduction of entropy across |
+ all contexts. */ |
+ double* entropy = BROTLI_ALLOC(m, double, num_contexts); |
+ HistogramLiteral* combined_histo = |
+ BROTLI_ALLOC(m, HistogramLiteral, 2 * num_contexts); |
+ double* combined_entropy = BROTLI_ALLOC(m, double, 2 * num_contexts); |
+ double diff[2] = { 0.0 }; |
+ size_t i; |
+ if (BROTLI_IS_OOM(m)) return; |
+ for (i = 0; i < num_contexts; ++i) { |
+ size_t curr_histo_ix = self->curr_histogram_ix_ + i; |
+ size_t j; |
+ entropy[i] = BitsEntropy(histograms[curr_histo_ix].data_, |
+ self->alphabet_size_); |
+ for (j = 0; j < 2; ++j) { |
+ size_t jx = j * num_contexts + i; |
+ size_t last_histogram_ix = self->last_histogram_ix_[j] + i; |
+ combined_histo[jx] = histograms[curr_histo_ix]; |
+ HistogramAddHistogramLiteral(&combined_histo[jx], |
+ &histograms[last_histogram_ix]); |
+ combined_entropy[jx] = BitsEntropy( |
+ &combined_histo[jx].data_[0], self->alphabet_size_); |
+ diff[j] += combined_entropy[jx] - entropy[i] - last_entropy[jx]; |
+ } |
+ } |
+ |
+ if (split->num_types < self->max_block_types_ && |
+ diff[0] > self->split_threshold_ && |
+ diff[1] > self->split_threshold_) { |
+ /* Create new block. */ |
+ split->lengths[self->num_blocks_] = (uint32_t)self->block_size_; |
+ split->types[self->num_blocks_] = (uint8_t)split->num_types; |
+ self->last_histogram_ix_[1] = self->last_histogram_ix_[0]; |
+ self->last_histogram_ix_[0] = split->num_types * num_contexts; |
+ for (i = 0; i < num_contexts; ++i) { |
+ last_entropy[num_contexts + i] = last_entropy[i]; |
+ last_entropy[i] = entropy[i]; |
+ } |
+ ++self->num_blocks_; |
+ ++split->num_types; |
+ self->curr_histogram_ix_ += num_contexts; |
+ if (self->curr_histogram_ix_ < *self->histograms_size_) { |
+ ClearHistogramsLiteral( |
+ &self->histograms_[self->curr_histogram_ix_], self->num_contexts_); |
+ } |
+ self->block_size_ = 0; |
+ self->merge_last_count_ = 0; |
+ self->target_block_size_ = self->min_block_size_; |
+ } else if (diff[1] < diff[0] - 20.0) { |
+ /* Combine this block with second last block. */ |
+ split->lengths[self->num_blocks_] = (uint32_t)self->block_size_; |
+ split->types[self->num_blocks_] = split->types[self->num_blocks_ - 2]; |
+ BROTLI_SWAP(size_t, self->last_histogram_ix_, 0, 1); |
+ for (i = 0; i < num_contexts; ++i) { |
+ histograms[self->last_histogram_ix_[0] + i] = |
+ combined_histo[num_contexts + i]; |
+ last_entropy[num_contexts + i] = last_entropy[i]; |
+ last_entropy[i] = combined_entropy[num_contexts + i]; |
+ HistogramClearLiteral(&histograms[self->curr_histogram_ix_ + i]); |
+ } |
+ ++self->num_blocks_; |
+ self->block_size_ = 0; |
+ self->merge_last_count_ = 0; |
+ self->target_block_size_ = self->min_block_size_; |
+ } else { |
+ /* Combine this block with last block. */ |
+ split->lengths[self->num_blocks_ - 1] += (uint32_t)self->block_size_; |
+ for (i = 0; i < num_contexts; ++i) { |
+ histograms[self->last_histogram_ix_[0] + i] = combined_histo[i]; |
+ last_entropy[i] = combined_entropy[i]; |
+ if (split->num_types == 1) { |
+ last_entropy[num_contexts + i] = last_entropy[i]; |
+ } |
+ HistogramClearLiteral(&histograms[self->curr_histogram_ix_ + i]); |
+ } |
+ self->block_size_ = 0; |
+ if (++self->merge_last_count_ > 1) { |
+ self->target_block_size_ += self->min_block_size_; |
+ } |
+ } |
+ BROTLI_FREE(m, combined_entropy); |
+ BROTLI_FREE(m, combined_histo); |
+ BROTLI_FREE(m, entropy); |
+ } |
+ if (is_final) { |
+ *self->histograms_size_ = split->num_types * num_contexts; |
+ split->num_blocks = self->num_blocks_; |
+ } |
+} |
+ |
+/* Adds the next symbol to the current block type and context. When the |
+ current block reaches the target size, decides on merging the block. */ |
+static void ContextBlockSplitterAddSymbol(MemoryManager* m, |
+ ContextBlockSplitter* self, size_t symbol, size_t context) { |
+ HistogramAddLiteral(&self->histograms_[self->curr_histogram_ix_ + context], |
+ symbol); |
+ ++self->block_size_; |
+ if (self->block_size_ == self->target_block_size_) { |
+ ContextBlockSplitterFinishBlock(m, self, /* is_final = */ BROTLI_FALSE); |
+ if (BROTLI_IS_OOM(m)) return; |
+ } |
+} |
+ |
+void BrotliBuildMetaBlockGreedyWithContexts(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) { |
+ ContextBlockSplitter lit_blocks; |
+ BlockSplitterCommand cmd_blocks; |
+ BlockSplitterDistance dist_blocks; |
+ size_t num_literals = 0; |
+ size_t i; |
+ for (i = 0; i < n_commands; ++i) { |
+ num_literals += commands[i].insert_len_; |
+ } |
+ |
+ InitContextBlockSplitter(m, &lit_blocks, 256, num_contexts, 512, 400.0, |
+ num_literals, &mb->literal_split, &mb->literal_histograms, |
+ &mb->literal_histograms_size); |
+ if (BROTLI_IS_OOM(m)) return; |
+ InitBlockSplitterCommand(m, &cmd_blocks, BROTLI_NUM_COMMAND_SYMBOLS, 1024, |
+ 500.0, n_commands, &mb->command_split, &mb->command_histograms, |
+ &mb->command_histograms_size); |
+ if (BROTLI_IS_OOM(m)) return; |
+ InitBlockSplitterDistance(m, &dist_blocks, 64, 512, 100.0, n_commands, |
+ &mb->distance_split, &mb->distance_histograms, |
+ &mb->distance_histograms_size); |
+ if (BROTLI_IS_OOM(m)) return; |
+ |
+ for (i = 0; i < n_commands; ++i) { |
+ const Command cmd = commands[i]; |
+ size_t j; |
+ BlockSplitterAddSymbolCommand(&cmd_blocks, cmd.cmd_prefix_); |
+ for (j = cmd.insert_len_; j != 0; --j) { |
+ size_t context = Context(prev_byte, prev_byte2, literal_context_mode); |
+ uint8_t literal = ringbuffer[pos & mask]; |
+ ContextBlockSplitterAddSymbol( |
+ m, &lit_blocks, literal, static_context_map[context]); |
+ prev_byte2 = prev_byte; |
+ if (BROTLI_IS_OOM(m)) return; |
+ prev_byte = literal; |
+ ++pos; |
+ } |
+ pos += CommandCopyLen(&cmd); |
+ if (CommandCopyLen(&cmd)) { |
+ prev_byte2 = ringbuffer[(pos - 2) & mask]; |
+ prev_byte = ringbuffer[(pos - 1) & mask]; |
+ if (cmd.cmd_prefix_ >= 128) { |
+ BlockSplitterAddSymbolDistance(&dist_blocks, cmd.dist_prefix_); |
+ } |
+ } |
+ } |
+ |
+ ContextBlockSplitterFinishBlock(m, &lit_blocks, /* is_final = */ BROTLI_TRUE); |
+ if (BROTLI_IS_OOM(m)) return; |
+ CleanupContextBlockSplitter(m, &lit_blocks); |
+ BlockSplitterFinishBlockCommand(&cmd_blocks, /* is_final = */ BROTLI_TRUE); |
+ BlockSplitterFinishBlockDistance(&dist_blocks, /* is_final = */ BROTLI_TRUE); |
+ |
+ assert(mb->literal_context_map == 0); |
+ mb->literal_context_map_size = |
+ mb->literal_split.num_types << BROTLI_LITERAL_CONTEXT_BITS; |
+ mb->literal_context_map = |
+ BROTLI_ALLOC(m, uint32_t, mb->literal_context_map_size); |
+ if (BROTLI_IS_OOM(m)) return; |
+ |
+ for (i = 0; i < mb->literal_split.num_types; ++i) { |
+ size_t j; |
+ for (j = 0; j < (1u << BROTLI_LITERAL_CONTEXT_BITS); ++j) { |
+ mb->literal_context_map[(i << BROTLI_LITERAL_CONTEXT_BITS) + j] = |
+ (uint32_t)(i * num_contexts) + static_context_map[j]; |
+ } |
+ } |
+} |
+ |
+void BrotliOptimizeHistograms(size_t num_direct_distance_codes, |
+ size_t distance_postfix_bits, |
+ MetaBlockSplit* mb) { |
+ uint8_t good_for_rle[BROTLI_NUM_COMMAND_SYMBOLS]; |
+ size_t num_distance_codes; |
+ size_t i; |
+ for (i = 0; i < mb->literal_histograms_size; ++i) { |
+ BrotliOptimizeHuffmanCountsForRle(256, mb->literal_histograms[i].data_, |
+ good_for_rle); |
+ } |
+ for (i = 0; i < mb->command_histograms_size; ++i) { |
+ BrotliOptimizeHuffmanCountsForRle(BROTLI_NUM_COMMAND_SYMBOLS, |
+ mb->command_histograms[i].data_, |
+ good_for_rle); |
+ } |
+ num_distance_codes = BROTLI_NUM_DISTANCE_SHORT_CODES + |
+ num_direct_distance_codes + |
+ ((2 * BROTLI_MAX_DISTANCE_BITS) << distance_postfix_bits); |
+ for (i = 0; i < mb->distance_histograms_size; ++i) { |
+ BrotliOptimizeHuffmanCountsForRle(num_distance_codes, |
+ mb->distance_histograms[i].data_, |
+ good_for_rle); |
+ } |
+} |
+ |
+#if defined(__cplusplus) || defined(c_plusplus) |
+} /* extern "C" */ |
+#endif |