| 1 | /* |
| 2 | * AVR demuxer |
| 3 | * Copyright (c) 2012 Paul B Mahol |
| 4 | * |
| 5 | * This file is part of FFmpeg. |
| 6 | * |
| 7 | * FFmpeg is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU Lesser General Public |
| 9 | * License as published by the Free Software Foundation; either |
| 10 | * version 2.1 of the License, or (at your option) any later version. |
| 11 | * |
| 12 | * FFmpeg is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * Lesser General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU Lesser General Public |
| 18 | * License along with FFmpeg; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | #include "libavutil/intreadwrite.h" |
| 23 | #include "avformat.h" |
| 24 | #include "internal.h" |
| 25 | #include "pcm.h" |
| 26 | |
| 27 | static int avr_probe(AVProbeData *p) |
| 28 | { |
| 29 | if (AV_RL32(p->buf) != MKTAG('2', 'B', 'I', 'T')) |
| 30 | return 0; |
| 31 | |
| 32 | if (!AV_RB16(p->buf+12) || AV_RB16(p->buf+12) > 256) // channels |
| 33 | return AVPROBE_SCORE_EXTENSION/2; |
| 34 | if (AV_RB16(p->buf+14) > 256) // bps |
| 35 | return AVPROBE_SCORE_EXTENSION/2; |
| 36 | |
| 37 | return AVPROBE_SCORE_EXTENSION; |
| 38 | } |
| 39 | |
| 40 | static int avr_read_header(AVFormatContext *s) |
| 41 | { |
| 42 | uint16_t chan, sign, bps; |
| 43 | AVStream *st; |
| 44 | |
| 45 | st = avformat_new_stream(s, NULL); |
| 46 | if (!st) |
| 47 | return AVERROR(ENOMEM); |
| 48 | |
| 49 | st->codec->codec_type = AVMEDIA_TYPE_AUDIO; |
| 50 | |
| 51 | avio_skip(s->pb, 4); // magic |
| 52 | avio_skip(s->pb, 8); // sample_name |
| 53 | |
| 54 | chan = avio_rb16(s->pb); |
| 55 | if (!chan) { |
| 56 | st->codec->channels = 1; |
| 57 | } else if (chan == 0xFFFFu) { |
| 58 | st->codec->channels = 2; |
| 59 | } else { |
| 60 | avpriv_request_sample(s, "chan %d", chan); |
| 61 | return AVERROR_PATCHWELCOME; |
| 62 | } |
| 63 | |
| 64 | st->codec->bits_per_coded_sample = bps = avio_rb16(s->pb); |
| 65 | |
| 66 | sign = avio_rb16(s->pb); |
| 67 | |
| 68 | avio_skip(s->pb, 2); // loop |
| 69 | avio_skip(s->pb, 2); // midi |
| 70 | avio_skip(s->pb, 1); // replay speed |
| 71 | |
| 72 | st->codec->sample_rate = avio_rb24(s->pb); |
| 73 | avio_skip(s->pb, 4 * 3); |
| 74 | avio_skip(s->pb, 2 * 3); |
| 75 | avio_skip(s->pb, 20); |
| 76 | avio_skip(s->pb, 64); |
| 77 | |
| 78 | st->codec->codec_id = ff_get_pcm_codec_id(bps, 0, 1, sign); |
| 79 | if (st->codec->codec_id == AV_CODEC_ID_NONE) { |
| 80 | avpriv_request_sample(s, "Bps %d and sign %d", bps, sign); |
| 81 | return AVERROR_PATCHWELCOME; |
| 82 | } |
| 83 | |
| 84 | st->codec->block_align = bps * st->codec->channels / 8; |
| 85 | |
| 86 | avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate); |
| 87 | return 0; |
| 88 | } |
| 89 | |
| 90 | AVInputFormat ff_avr_demuxer = { |
| 91 | .name = "avr", |
| 92 | .long_name = NULL_IF_CONFIG_SMALL("AVR (Audio Visual Research)"), |
| 93 | .read_probe = avr_probe, |
| 94 | .read_header = avr_read_header, |
| 95 | .read_packet = ff_pcm_read_packet, |
| 96 | .read_seek = ff_pcm_read_seek, |
| 97 | .extensions = "avr", |
| 98 | .flags = AVFMT_GENERIC_INDEX, |
| 99 | }; |