blob: 294160e024047467bafbac72d1c3baef0d063595
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->codecpar->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->codecpar->channels = 1; |
57 | } else if (chan == 0xFFFFu) { |
58 | st->codecpar->channels = 2; |
59 | } else { |
60 | avpriv_request_sample(s, "chan %d", chan); |
61 | return AVERROR_PATCHWELCOME; |
62 | } |
63 | |
64 | st->codecpar->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->codecpar->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->codecpar->codec_id = ff_get_pcm_codec_id(bps, 0, 1, sign); |
79 | if (st->codecpar->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->codecpar->block_align = bps * st->codecpar->channels / 8; |
85 | |
86 | avpriv_set_pts_info(st, 64, 1, st->codecpar->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 | }; |
100 |