mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-23 12:43:46 +02:00
92 lines
3.3 KiB
C
92 lines
3.3 KiB
C
/*
|
|
* 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;
|
|
const uint8_t *buf_ptr;
|
|
int len, sample_rate, bit_rate, channels, samples;
|
|
|
|
*poutbuf = NULL;
|
|
*poutbuf_size = 0;
|
|
|
|
buf_ptr = buf;
|
|
while (buf_size > 0) {
|
|
len = s->inbuf_ptr - s->inbuf;
|
|
if (s->frame_size == 0) {
|
|
/* no header seen : find one. We need at least s->header_size
|
|
bytes to parse it */
|
|
len = FFMIN(s->header_size - len, buf_size);
|
|
|
|
memcpy(s->inbuf_ptr, buf_ptr, len);
|
|
buf_ptr += len;
|
|
s->inbuf_ptr += len;
|
|
buf_size -= len;
|
|
if ((s->inbuf_ptr - s->inbuf) == s->header_size) {
|
|
len = s->sync(s->inbuf, &channels, &sample_rate, &bit_rate,
|
|
&samples);
|
|
if (len == 0) {
|
|
/* no sync found : move by one byte (inefficient, but simple!) */
|
|
memmove(s->inbuf, s->inbuf + 1, s->header_size - 1);
|
|
s->inbuf_ptr--;
|
|
} else {
|
|
s->frame_size = len;
|
|
/* update codec info */
|
|
avctx->sample_rate = sample_rate;
|
|
/* set channels,except if the user explicitly requests 1 or 2 channels, XXX/FIXME this is a bit ugly */
|
|
if(avctx->codec_id == CODEC_ID_AC3){
|
|
if(avctx->channels!=1 && avctx->channels!=2){
|
|
avctx->channels = channels;
|
|
}
|
|
} else {
|
|
avctx->channels = channels;
|
|
}
|
|
avctx->bit_rate = bit_rate;
|
|
avctx->frame_size = samples;
|
|
}
|
|
}
|
|
} else {
|
|
len = FFMIN(s->frame_size - len, buf_size);
|
|
|
|
memcpy(s->inbuf_ptr, buf_ptr, len);
|
|
buf_ptr += len;
|
|
s->inbuf_ptr += len;
|
|
buf_size -= len;
|
|
|
|
if(s->inbuf_ptr - s->inbuf == s->frame_size){
|
|
*poutbuf = s->inbuf;
|
|
*poutbuf_size = s->frame_size;
|
|
s->inbuf_ptr = s->inbuf;
|
|
s->frame_size = 0;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
return buf_ptr - buf;
|
|
}
|