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/*
* AVR demuxer
* Copyright (c) 2012 Paul B Mahol
*
* 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 "libavutil/intreadwrite.h"
#include "avformat.h"
#include "demux.h"
#include "internal.h"
#include "pcm.h"
static int avr_probe(const AVProbeData *p)
{
if (AV_RL32(p->buf) != MKTAG('2', 'B', 'I', 'T'))
return 0;
if (!AV_RB16(p->buf+12) || AV_RB16(p->buf+12) > 256) // channels
return AVPROBE_SCORE_EXTENSION/2;
if (AV_RB16(p->buf+14) > 256) // bps
return AVPROBE_SCORE_EXTENSION/2;
return AVPROBE_SCORE_EXTENSION;
}
static int avr_read_header(AVFormatContext *s)
{
uint16_t chan, sign, bps;
AVStream *st;
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
avio_skip(s->pb, 4); // magic
avio_skip(s->pb, 8); // sample_name
chan = avio_rb16(s->pb);
if (!chan) {
st->codecpar->ch_layout.nb_channels = 1;
} else if (chan == 0xFFFFu) {
st->codecpar->ch_layout.nb_channels = 2;
} else {
avpriv_request_sample(s, "chan %d", chan);
return AVERROR_PATCHWELCOME;
}
st->codecpar->bits_per_coded_sample = bps = avio_rb16(s->pb);
sign = avio_rb16(s->pb);
avio_skip(s->pb, 2); // loop
avio_skip(s->pb, 2); // midi
avio_skip(s->pb, 1); // replay speed
st->codecpar->sample_rate = avio_rb24(s->pb);
if (st->codecpar->sample_rate == 0)
return AVERROR_INVALIDDATA;
avio_skip(s->pb, 4 * 3);
avio_skip(s->pb, 2 * 3);
avio_skip(s->pb, 20);
avio_skip(s->pb, 64);
st->codecpar->codec_id = ff_get_pcm_codec_id(bps, 0, 1, sign);
if (st->codecpar->codec_id == AV_CODEC_ID_NONE) {
avpriv_request_sample(s, "Bps %d and sign %d", bps, sign);
return AVERROR_PATCHWELCOME;
}
st->codecpar->block_align = bps * st->codecpar->ch_layout.nb_channels / 8;
avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
return 0;
}
const FFInputFormat ff_avr_demuxer = {
.p.name = "avr",
.p.long_name = NULL_IF_CONFIG_SMALL("AVR (Audio Visual Research)"),
.p.extensions = "avr",
.p.flags = AVFMT_GENERIC_INDEX,
.read_probe = avr_probe,
.read_header = avr_read_header,
.read_packet = ff_pcm_read_packet,
.read_seek = ff_pcm_read_seek,
};
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