yading@11: /*
yading@11:  * AVR demuxer
yading@11:  * Copyright (c) 2012 Paul B Mahol
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: #include "libavutil/intreadwrite.h"
yading@11: #include "avformat.h"
yading@11: #include "internal.h"
yading@11: #include "pcm.h"
yading@11: 
yading@11: static int avr_probe(AVProbeData *p)
yading@11: {
yading@11:     if (AV_RL32(p->buf) == MKTAG('2', 'B', 'I', 'T'))
yading@11:         return AVPROBE_SCORE_MAX / 2;
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int avr_read_header(AVFormatContext *s)
yading@11: {
yading@11:     uint16_t chan, sign, bps;
yading@11:     AVStream *st;
yading@11: 
yading@11:     st = avformat_new_stream(s, NULL);
yading@11:     if (!st)
yading@11:         return AVERROR(ENOMEM);
yading@11: 
yading@11:     st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
yading@11: 
yading@11:     avio_skip(s->pb, 4); // magic
yading@11:     avio_skip(s->pb, 8); // sample_name
yading@11: 
yading@11:     chan = avio_rb16(s->pb);
yading@11:     if (!chan) {
yading@11:         st->codec->channels = 1;
yading@11:     } else if (chan == 0xFFFFu) {
yading@11:         st->codec->channels = 2;
yading@11:     } else {
yading@11:         avpriv_request_sample(s, "chan %d", chan);
yading@11:         return AVERROR_PATCHWELCOME;
yading@11:     }
yading@11: 
yading@11:     st->codec->bits_per_coded_sample = bps = avio_rb16(s->pb);
yading@11: 
yading@11:     sign = avio_rb16(s->pb);
yading@11: 
yading@11:     avio_skip(s->pb, 2); // loop
yading@11:     avio_skip(s->pb, 2); // midi
yading@11:     avio_skip(s->pb, 1); // replay speed
yading@11: 
yading@11:     st->codec->sample_rate = avio_rb24(s->pb);
yading@11:     avio_skip(s->pb, 4 * 3);
yading@11:     avio_skip(s->pb, 2 * 3);
yading@11:     avio_skip(s->pb, 20);
yading@11:     avio_skip(s->pb, 64);
yading@11: 
yading@11:     if (!sign && bps == 8) {
yading@11:         st->codec->codec_id = AV_CODEC_ID_PCM_U8;
yading@11:     } else if (!sign && bps == 16) {
yading@11:         st->codec->codec_id = AV_CODEC_ID_PCM_U16BE;
yading@11:     } else if (sign == 0xFFFFu && bps == 8) {
yading@11:         st->codec->codec_id = AV_CODEC_ID_PCM_S8;
yading@11:     } else if (sign == 0xFFFFu && bps == 16) {
yading@11:         st->codec->codec_id = AV_CODEC_ID_PCM_S16BE;
yading@11:     } else {
yading@11:         avpriv_request_sample(s, "bits per sample %d", bps);
yading@11:         return AVERROR_PATCHWELCOME;
yading@11:     }
yading@11: 
yading@11:     st->codec->block_align = bps * st->codec->channels / 8;
yading@11: 
yading@11:     avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: AVInputFormat ff_avr_demuxer = {
yading@11:     .name           = "avr",
yading@11:     .long_name      = NULL_IF_CONFIG_SMALL("AVR (Audio Visual Research)"),
yading@11:     .read_probe     = avr_probe,
yading@11:     .read_header    = avr_read_header,
yading@11:     .read_packet    = ff_pcm_read_packet,
yading@11:     .read_seek      = ff_pcm_read_seek,
yading@11:     .extensions     = "avr",
yading@11:     .flags          = AVFMT_GENERIC_INDEX,
yading@11: };