| /* |
| * 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 "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->channels = 1; |
| } else if (chan == 0xFFFFu) { |
| st->codecpar->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); |
| 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->channels / 8; |
| |
| avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate); |
| return 0; |
| } |
| |
| AVInputFormat ff_avr_demuxer = { |
| .name = "avr", |
| .long_name = NULL_IF_CONFIG_SMALL("AVR (Audio Visual Research)"), |
| .read_probe = avr_probe, |
| .read_header = avr_read_header, |
| .read_packet = ff_pcm_read_packet, |
| .read_seek = ff_pcm_read_seek, |
| .extensions = "avr", |
| .flags = AVFMT_GENERIC_INDEX, |
| }; |