FFmpeg  4.0
mlz.h
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1 /*
2  * Copyright (c) 2016 Umair Khan <omerjerk@gmail.com>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef AVCODEC_MLZ_H
22 #define AVCODEC_MLZ_H
23 
24 #include "get_bits.h"
25 
26 #define CODE_UNSET -1
27 #define CODE_BIT_INIT 9
28 #define DIC_INDEX_INIT 512 // 2^9
29 #define DIC_INDEX_MAX 32768 // 2^15
30 #define FLUSH_CODE 256
31 #define FREEZE_CODE 257
32 #define FIRST_CODE 258
33 #define MAX_CODE 32767
34 #define TABLE_SIZE 35023 // TABLE_SIZE must be a prime number
35 
36 /** Dictionary structure for mlz decompression
37  */
38 typedef struct MLZDict {
41  int char_code;
42  int match_len;
43 } MLZDict;
44 
45 /** MLZ data strucure
46  */
47 typedef struct MLZ {
50  unsigned int bump_code;
51  unsigned int flush_code;
52  int next_code;
55  void* context;
56 } MLZ;
57 
58 /** Initialize the dictionary
59  */
60 void ff_mlz_init_dict(void* context, MLZ *mlz);
61 
62 /** Flush the dictionary
63  */
64 void ff_mlz_flush_dict(MLZ *dict);
65 
66 /** Run mlz decompression on the next size bits and the output will be stored in buff
67  */
68 int ff_mlz_decompression(MLZ* mlz, GetBitContext* gb, int size, unsigned char *buff);
69 
70 #endif /*AVCODEC_MLZ_H*/
Dictionary structure for mlz decompression.
Definition: mlz.h:38
int size
void ff_mlz_flush_dict(MLZ *dict)
Flush the dictionary.
Definition: mlz.c:35
int dic_code_bit
Definition: mlz.h:48
int ff_mlz_decompression(MLZ *mlz, GetBitContext *gb, int size, unsigned char *buff)
Run mlz decompression on the next size bits and the output will be stored in buff.
Definition: mlz.c:123
bitstream reader API header.
MLZDict * dict
Definition: mlz.h:54
int parent_code
Definition: mlz.h:40
unsigned int bump_code
Definition: mlz.h:50
unsigned int flush_code
Definition: mlz.h:51
int char_code
Definition: mlz.h:41
MLZ data strucure.
Definition: mlz.h:47
void ff_mlz_init_dict(void *context, MLZ *mlz)
Initialize the dictionary.
Definition: mlz.c:23
int match_len
Definition: mlz.h:42
int freeze_flag
Definition: mlz.h:53
int string_code
Definition: mlz.h:39
void * context
Definition: mlz.h:55
int current_dic_index_max
Definition: mlz.h:49
int next_code
Definition: mlz.h:52