1 /*
2 * DERF demuxer
3 * Copyright (c) 2020 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/channel_layout.h"
23 #include "libavutil/intreadwrite.h"
24 #include "avformat.h"
25 #include "internal.h"
26 #include "pcm.h"
27
derf_probe(const AVProbeData *p)28 static int derf_probe(const AVProbeData *p)
29 {
30 if (AV_RL32(p->buf) != MKTAG('D','E','R','F'))
31 return 0;
32 if (AV_RL32(p->buf+4) != 1 && AV_RL32(p->buf+4) != 2)
33 return 0;
34
35 return AVPROBE_SCORE_MAX / 3 * 2;
36 }
37
derf_read_header(AVFormatContext *s)38 static int derf_read_header(AVFormatContext *s)
39 {
40 unsigned data_size;
41 int channels;
42 AVIOContext *pb = s->pb;
43 AVCodecParameters *par;
44 AVStream *st;
45
46 avio_skip(pb, 4);
47
48 st = avformat_new_stream(s, NULL);
49 if (!st)
50 return AVERROR(ENOMEM);
51
52 par = st->codecpar;
53 par->codec_type = AVMEDIA_TYPE_AUDIO;
54 par->codec_id = AV_CODEC_ID_DERF_DPCM;
55 par->format = AV_SAMPLE_FMT_S16;
56 channels = avio_rl32(pb);
57 if (channels != 1 && channels != 2)
58 return AVERROR_INVALIDDATA;
59 av_channel_layout_default(&par->ch_layout, channels);
60 data_size = avio_rl32(pb);
61 st->duration = data_size / channels;
62 par->sample_rate = 22050;
63 par->block_align = 1;
64
65 avpriv_set_pts_info(st, 64, 1, par->sample_rate);
66
67 return 0;
68 }
69
70 const AVInputFormat ff_derf_demuxer = {
71 .name = "derf",
72 .long_name = NULL_IF_CONFIG_SMALL("Xilam DERF"),
73 .read_probe = derf_probe,
74 .read_header = derf_read_header,
75 .read_packet = ff_pcm_read_packet,
76 .read_seek = ff_pcm_read_seek,
77 .extensions = "adp",
78 };
79