FFmpeg
elsdec.h
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1 /*
2  * ELS (Entropy Logarithmic-Scale) decoder
3  *
4  * Copyright (c) 2013 Maxim Poliakovski
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * Entropy Logarithmic-Scale binary arithmetic coder
26  */
27 
28 #ifndef AVCODEC_ELSDEC_H
29 #define AVCODEC_ELSDEC_H
30 
31 #include <stdint.h>
32 #include <sys/types.h>
33 
34 #define ELS_EXPGOLOMB_LEN 10
35 
36 typedef struct ElsDecCtx {
37  const uint8_t *in_buf;
38  unsigned x;
39  size_t data_size;
40  int j, t, diff, err;
41 } ElsDecCtx;
42 
43 typedef struct ElsRungNode {
44  uint8_t rung;
45  uint16_t next_index;
46 } ElsRungNode;
47 
48 typedef struct ElsUnsignedRung {
52  uint16_t avail_index;
54 
55 void ff_els_decoder_init(ElsDecCtx *ctx, const uint8_t *in, size_t data_size);
57 int ff_els_decode_bit(ElsDecCtx *ctx, unsigned char *rung);
59 
60 #endif /* AVCODEC_ELSDEC_H */
ElsRungNode::rung
uint8_t rung
Definition: elsdec.h:44
ElsDecCtx::err
int err
Definition: elsdec.h:40
ff_els_decode_unsigned
unsigned ff_els_decode_unsigned(ElsDecCtx *ctx, ElsUnsignedRung *ur)
Definition: elsdec.c:350
ElsDecCtx::in_buf
const uint8_t * in_buf
Definition: elsdec.h:37
ElsRungNode::next_index
uint16_t next_index
Definition: elsdec.h:45
ElsDecCtx::diff
int diff
Definition: elsdec.h:40
ElsDecCtx::x
unsigned x
Definition: elsdec.h:38
ff_els_decoder_init
void ff_els_decoder_init(ElsDecCtx *ctx, const uint8_t *in, size_t data_size)
Definition: elsdec.c:247
ElsUnsignedRung::avail_index
uint16_t avail_index
Definition: elsdec.h:52
ElsDecCtx::t
int t
Definition: elsdec.h:40
ElsDecCtx::j
int j
Definition: elsdec.h:40
ctx
AVFormatContext * ctx
Definition: movenc.c:48
ff_els_decoder_uninit
void ff_els_decoder_uninit(ElsUnsignedRung *rung)
Definition: elsdec.c:272
ElsRungNode
Definition: elsdec.h:43
ElsUnsignedRung
Definition: elsdec.h:48
ELS_EXPGOLOMB_LEN
#define ELS_EXPGOLOMB_LEN
Definition: elsdec.h:34
ElsDecCtx
Definition: elsdec.h:36
ElsUnsignedRung::rem_rung_list
ElsRungNode * rem_rung_list
Definition: elsdec.h:50
ElsUnsignedRung::rung_list_size
size_t rung_list_size
Definition: elsdec.h:51
ff_els_decode_bit
int ff_els_decode_bit(ElsDecCtx *ctx, unsigned char *rung)
ElsUnsignedRung::prefix_rung
uint8_t prefix_rung[ELS_EXPGOLOMB_LEN+1]
Definition: elsdec.h:49
ElsDecCtx::data_size
size_t data_size
Definition: elsdec.h:39