mirror of
https://github.com/google/brotli.git
synced 2024-11-24 12:30:15 +00:00
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.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
|
|
Utilities for building Huffman decoding tables.
|
|
*/
|
|
|
|
#ifndef BROTLI_DEC_HUFFMAN_H_
|
|
#define BROTLI_DEC_HUFFMAN_H_
|
|
|
|
#include <assert.h>
|
|
#include "./types.h"
|
|
|
|
#if defined(__cplusplus) || defined(c_plusplus)
|
|
extern "C" {
|
|
#endif
|
|
|
|
typedef struct {
|
|
uint8_t bits; /* number of bits used for this symbol */
|
|
uint16_t value; /* symbol value or table offset */
|
|
} HuffmanCode;
|
|
|
|
/* Builds Huffman lookup table assuming code lengths are in symbol order. */
|
|
/* Returns false in case of error (invalid tree or memory error). */
|
|
int BrotliBuildHuffmanTable(HuffmanCode* root_table,
|
|
int root_bits,
|
|
const uint8_t* const code_lengths,
|
|
int code_lengths_size);
|
|
|
|
#if defined(__cplusplus) || defined(c_plusplus)
|
|
} /* extern "C" */
|
|
#endif
|
|
|
|
#endif /* BROTLI_DEC_HUFFMAN_H_ */
|