ffmpeg/libavformat/oggparseflac.c

83 lines
2.5 KiB
C

/*
* Copyright (C) 2005 Matthieu CASTET
*
* 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 <stdlib.h>
#include "avformat.h"
#include "bitstream.h"
#include "ogg2.h"
#define FLAC_STREAMINFO_SIZE 0x22
static int
flac_header (AVFormatContext * s, int idx)
{
ogg_t *ogg = s->priv_data;
ogg_stream_t *os = ogg->streams + idx;
AVStream *st = s->streams[idx];
GetBitContext gb;
int mdt;
if (os->buf[os->pstart] == 0xff)
return 0;
init_get_bits(&gb, os->buf + os->pstart, os->psize*8);
get_bits(&gb, 1); /* metadata_last */
mdt = get_bits(&gb, 7);
if (mdt == 0x7f) {
skip_bits(&gb, 4*8); /* "FLAC" */
if(get_bits(&gb, 8) != 1) /* unsupported major version */
return -1;
skip_bits(&gb, 8 + 16); /* minor version + header count */
skip_bits(&gb, 4*8); /* "fLaC" */
/* METADATA_BLOCK_HEADER */
if (get_bits_long(&gb, 32) != FLAC_STREAMINFO_SIZE)
return -1;
skip_bits(&gb, 16*2+24*2);
st->codec->sample_rate = get_bits_long(&gb, 20);
st->codec->channels = get_bits(&gb, 3) + 1;
st->codec->codec_type = CODEC_TYPE_AUDIO;
st->codec->codec_id = CODEC_ID_FLAC;
st->codec->extradata =
av_malloc(FLAC_STREAMINFO_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
memcpy (st->codec->extradata, os->buf + os->pstart + 5 + 4 + 4 + 4,
FLAC_STREAMINFO_SIZE);
st->codec->extradata_size = FLAC_STREAMINFO_SIZE;
st->time_base.num = 1;
st->time_base.den = st->codec->sample_rate;
} else if (mdt == 4) {
vorbis_comment (s, os->buf + os->pstart + 4, os->psize - 4);
}
return 1;
}
ogg_codec_t flac_codec = {
.magic = "\177FLAC",
.magicsize = 5,
.header = flac_header
};