1 /*
2 * This file is part of FFmpeg.
3 *
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
8 *
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18
19 /**
20 * @file
21 * Sipr audio parser
22 */
23
24 #include "parser.h"
25
26 typedef struct SiprParserContext{
27 ParseContext pc;
28 } SiprParserContext;
29
sipr_split(AVCodecContext * avctx,const uint8_t * buf,int buf_size)30 static int sipr_split(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
31 {
32 int next;
33
34 switch (avctx->block_align) {
35 case 20:
36 case 19:
37 case 29:
38 case 37: next = avctx->block_align; break;
39 default:
40 if (avctx->bit_rate > 12200) next = 20;
41 else if (avctx->bit_rate > 7500 ) next = 19;
42 else if (avctx->bit_rate > 5750 ) next = 29;
43 else next = 37;
44 }
45
46 return FFMIN(next, buf_size);
47 }
48
sipr_parse(AVCodecParserContext * s1,AVCodecContext * avctx,const uint8_t ** poutbuf,int * poutbuf_size,const uint8_t * buf,int buf_size)49 static int sipr_parse(AVCodecParserContext *s1, AVCodecContext *avctx,
50 const uint8_t **poutbuf, int *poutbuf_size,
51 const uint8_t *buf, int buf_size)
52 {
53 SiprParserContext *s = s1->priv_data;
54 ParseContext *pc = &s->pc;
55 int next;
56
57 next = sipr_split(avctx, buf, buf_size);
58 if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
59 *poutbuf = NULL;
60 *poutbuf_size = 0;
61 return buf_size;
62 }
63
64 *poutbuf = buf;
65 *poutbuf_size = buf_size;
66 return next;
67 }
68
69 AVCodecParser ff_sipr_parser = {
70 .codec_ids = { AV_CODEC_ID_SIPR },
71 .priv_data_size = sizeof(SiprParserContext),
72 .parser_parse = sipr_parse,
73 .parser_close = ff_parse_close,
74 };
75