PeerStreamer

/*

 *    Copyright (C) 2005  Matthieu CASTET

 *

 * This library 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 of the License, or (at your option) any later version.

 *

 * This library 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 this library; 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(&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;

    } 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

};