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0454ab4ec0
This commit contains a batch of changes that were made to the Brotli
compression algorithm in the last month. Most important changes:
* Fixes to the spec.
* Change of code length code order.
* Use a 2-level Huffman lookup table in the decoder.
* Faster uncompressed meta-block decoding.
* Optimized encoding of the Huffman code.
* Detection of UTF-8 input encoding.
* UTF-8 based literal cost modeling for improved
backward reference selection.
45 lines
1.4 KiB
C
45 lines
1.4 KiB
C
/* Copyright 2013 Google Inc. All Rights Reserved.
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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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http://www.apache.org/licenses/LICENSE-2.0
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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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Utilities for building Huffman decoding tables.
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*/
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#ifndef BROTLI_DEC_HUFFMAN_H_
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#define BROTLI_DEC_HUFFMAN_H_
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#include <assert.h>
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#include "./types.h"
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#if defined(__cplusplus) || defined(c_plusplus)
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extern "C" {
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#endif
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typedef struct {
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uint8_t bits; /* number of bits used for this symbol */
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uint16_t value; /* symbol value or table offset */
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} HuffmanCode;
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/* Builds Huffman lookup table assuming code lengths are in symbol order. */
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/* Returns false in case of error (invalid tree or memory error). */
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int BrotliBuildHuffmanTable(HuffmanCode* root_table,
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int root_bits,
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const uint8_t* const code_lengths,
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int code_lengths_size);
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#if defined(__cplusplus) || defined(c_plusplus)
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} /* extern "C" */
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#endif
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#endif /* BROTLI_DEC_HUFFMAN_H_ */
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