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/*
* Common AAC and AC3 parser
* Copyright (c) 2003 Fabrice Bellard.
* Copyright (c) 2003 Michael Niedermayer.
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "parser.h"
#include "aac_ac3_parser.h"
int ff_aac_ac3_parse(AVCodecParserContext *s1,
AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
AACAC3ParseContext *s = s1->priv_data;
ParseContext *pc = &s->pc;
int len, i;
while(s->remaining_size <= buf_size){
if(s->remaining_size && !s->need_next_header){
i= s->remaining_size;
s->remaining_size = 0;
goto output_frame;
}else{ //we need a header first
len=0;
for(i=s->remaining_size; i<buf_size; i++){
s->state = (s->state<<8) + buf[i];
if((len=s->sync(s->state, s, &s->need_next_header, &s->new_frame_start)))
break;
}
i-= s->header_size -1;
if(len>0){
s->remaining_size = len + i;
if(pc->index+i > 0 && s->new_frame_start){
s->remaining_size -= i; // remaining_size=len
output_frame:
if(!s->frame_in_buffer && 0){
s->frame_in_buffer=1;
buf+=i;
buf_size-=i;
continue;
}
ff_combine_frame(pc, i, &buf, &buf_size);
*poutbuf = buf;
*poutbuf_size = buf_size;
/* update codec info */
avctx->sample_rate = s->sample_rate;
/* allow downmixing to stereo (or mono for AC3) */
if(avctx->request_channels > 0 &&
avctx->request_channels < s->channels &&
(avctx->request_channels <= 2 ||
(avctx->request_channels == 1 &&
avctx->codec_id == CODEC_ID_AC3))) {
avctx->channels = avctx->request_channels;
} else {
avctx->channels = s->channels;
}
avctx->bit_rate = s->bit_rate;
avctx->frame_size = s->samples;
return i;
}
s->frame_in_buffer=1;
}else{
break;
}
}
}
ff_combine_frame(pc, END_NOT_FOUND, &buf, &buf_size);
s->remaining_size -= FFMIN(s->remaining_size, buf_size);
*poutbuf = NULL;
*poutbuf_size = 0;
return buf_size;
}
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