1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
|
/*
* ELS (Entropy Logarithmic-Scale) decoder
*
* Copyright (c) 2013 Maxim Poliakovski
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Entropy Logarithmic-Scale binary arithmetic coder
*/
#ifndef AVCODEC_ELSDEC_H
#define AVCODEC_ELSDEC_H
#include <stdint.h>
#include <sys/types.h>
#define ELS_EXPGOLOMB_LEN 10
typedef struct ElsDecCtx {
const uint8_t *in_buf;
unsigned x;
size_t data_size;
int j, t, diff, err;
} ElsDecCtx;
typedef struct ElsRungNode {
uint8_t rung;
uint16_t next_index;
} ElsRungNode;
typedef struct ElsUnsignedRung {
uint8_t prefix_rung[ELS_EXPGOLOMB_LEN + 1];
ElsRungNode *rem_rung_list;
size_t rung_list_size;
uint16_t avail_index;
} ElsUnsignedRung;
void ff_els_decoder_init(ElsDecCtx *ctx, const uint8_t *in, size_t data_size);
void ff_els_decoder_uninit(ElsUnsignedRung *rung);
int ff_els_decode_bit(ElsDecCtx *ctx, unsigned char *rung);
unsigned ff_els_decode_unsigned(ElsDecCtx *ctx, ElsUnsignedRung *ur);
#endif /* AVCODEC_ELSDEC_H */
|
