FFmpeg4/libavcodec/mlz.h

71 lines
2.0 KiB
C
Raw Permalink Normal View History

2023-07-02 12:20:28 +00:00
/*
* Copyright (c) 2016 Umair Khan <omerjerk@gmail.com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVCODEC_MLZ_H
#define AVCODEC_MLZ_H
#include "get_bits.h"
#define CODE_UNSET -1
#define CODE_BIT_INIT 9
#define DIC_INDEX_INIT 512 // 2^9
#define DIC_INDEX_MAX 32768 // 2^15
#define FLUSH_CODE 256
#define FREEZE_CODE 257
#define FIRST_CODE 258
#define MAX_CODE 32767
#define TABLE_SIZE 35023 // TABLE_SIZE must be a prime number
/** Dictionary structure for mlz decompression
*/
typedef struct MLZDict {
int string_code;
int parent_code;
int char_code;
int match_len;
} MLZDict;
/** MLZ data strucure
*/
typedef struct MLZ {
int dic_code_bit;
int current_dic_index_max;
unsigned int bump_code;
unsigned int flush_code;
int next_code;
int freeze_flag;
MLZDict* dict;
void* context;
} MLZ;
/** Initialize the dictionary
*/
void ff_mlz_init_dict(void* context, MLZ *mlz);
/** Flush the dictionary
*/
void ff_mlz_flush_dict(MLZ *dict);
/** Run mlz decompression on the next size bits and the output will be stored in buff
*/
int ff_mlz_decompression(MLZ* mlz, GetBitContext* gb, int size, unsigned char *buff);
#endif /*AVCODEC_MLZ_H*/