100l I broke AC3 in MPEG seeking.
[libav.git] / libavcodec / aac_ac3_parser.c
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1/*
2 * Common AAC and AC3 parser
3 * Copyright (c) 2003 Fabrice Bellard.
4 * Copyright (c) 2003 Michael Niedermayer.
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#include "parser.h"
24#include "aac_ac3_parser.h"
25
679c2294 26int ff_aac_ac3_parse(AVCodecParserContext *s1,
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27 AVCodecContext *avctx,
28 const uint8_t **poutbuf, int *poutbuf_size,
29 const uint8_t *buf, int buf_size)
30{
679c2294 31 AACAC3ParseContext *s = s1->priv_data;
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32 ParseContext *pc = &s->pc;
33 int len, i;
133ac890 34 int new_frame_start;
99ff31dc 35
8629e756 36get_next:
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37 i=END_NOT_FOUND;
38 if(s->remaining_size <= buf_size){
8629e756 39 if(s->remaining_size && !s->need_next_header){
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40 i= s->remaining_size;
41 s->remaining_size = 0;
42 }else{ //we need a header first
43 len=0;
44 for(i=s->remaining_size; i<buf_size; i++){
45 s->state = (s->state<<8) + buf[i];
133ac890 46 if((len=s->sync(s->state, s, &s->need_next_header, &new_frame_start)))
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47 break;
48 }
49 if(len<=0){
50 i=END_NOT_FOUND;
51 }else{
52 i-= s->header_size -1;
e4d5a185 53 s->remaining_size = len;
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54 if(!new_frame_start)
55 goto get_next;
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56 }
57 }
58 }
99ff31dc 59
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60 if(ff_combine_frame(pc, i, &buf, &buf_size)<0){
61 s->remaining_size -= FFMIN(s->remaining_size, buf_size);
62 *poutbuf = NULL;
63 *poutbuf_size = 0;
64 return buf_size;
65 }
469d8816 66
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67 *poutbuf = buf;
68 *poutbuf_size = buf_size;
211dd1e8 69
99ff31dc 70 /* update codec info */
c599e297 71 avctx->sample_rate = s->sample_rate;
ef7f2bb7 72 /* allow downmixing to stereo (or mono for AC3) */
f228eb73 73 if(avctx->request_channels > 0 &&
c599e297 74 avctx->request_channels < s->channels &&
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75 (avctx->request_channels <= 2 ||
76 (avctx->request_channels == 1 &&
77 avctx->codec_id == CODEC_ID_AC3))) {
f228eb73 78 avctx->channels = avctx->request_channels;
6cd325c1 79 } else {
c599e297 80 avctx->channels = s->channels;
f228eb73 81 }
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82 avctx->bit_rate = s->bit_rate;
83 avctx->frame_size = s->samples;
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84
85 return i;
99ff31dc 86}