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71 lines
2.2 KiB
71 lines
2.2 KiB
// Copyright 2015 Google Inc. All Rights Reserved. |
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// |
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// Licensed under the Apache License, Version 2.0 (the "License"); |
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// you may not use this file except in compliance with the License. |
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// You may obtain a copy of the License at |
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// |
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// http://www.apache.org/licenses/LICENSE-2.0 |
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// |
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// Unless required by applicable law or agreed to in writing, software |
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// distributed under the License is distributed on an "AS IS" BASIS, |
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
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// See the License for the specific language governing permissions and |
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// limitations under the License. |
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// |
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// Algorithms for distributing the literals and commands of a metablock between |
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// block types and contexts. |
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#ifndef BROTLI_ENC_METABLOCK_H_ |
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#define BROTLI_ENC_METABLOCK_H_ |
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#include <vector> |
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#include "./command.h" |
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#include "./histogram.h" |
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namespace brotli { |
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struct BlockSplit { |
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BlockSplit() : num_types(0) {} |
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int num_types; |
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std::vector<int> types; |
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std::vector<int> lengths; |
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}; |
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struct MetaBlockSplit { |
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BlockSplit literal_split; |
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BlockSplit command_split; |
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BlockSplit distance_split; |
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std::vector<int> literal_context_map; |
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std::vector<int> distance_context_map; |
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std::vector<HistogramLiteral> literal_histograms; |
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std::vector<HistogramCommand> command_histograms; |
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std::vector<HistogramDistance> distance_histograms; |
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}; |
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void BuildMetaBlock(const uint8_t* ringbuffer, |
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const size_t pos, |
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const size_t mask, |
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uint8_t prev_byte, |
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uint8_t prev_byte2, |
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const Command* cmds, |
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size_t num_commands, |
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int literal_context_mode, |
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bool enable_context_modleing, |
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MetaBlockSplit* mb); |
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void BuildMetaBlockGreedy(const uint8_t* ringbuffer, |
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size_t pos, |
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size_t mask, |
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const Command *commands, |
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size_t n_commands, |
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MetaBlockSplit* mb); |
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void OptimizeHistograms(int num_direct_distance_codes, |
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int distance_postfix_bits, |
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MetaBlockSplit* mb); |
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} // namespace brotli |
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#endif // BROTLI_ENC_METABLOCK_H_
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