1 /*
2 * SVAG demuxer
3 * Copyright (c) 2015 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 "avformat.h"
23 #include "internal.h"
24
svag_probe(const AVProbeData * p)25 static int svag_probe(const AVProbeData *p)
26 {
27 if (memcmp(p->buf, "Svag", 4))
28 return 0;
29
30 return AVPROBE_SCORE_MAX;
31 }
32
svag_read_header(AVFormatContext * s)33 static int svag_read_header(AVFormatContext *s)
34 {
35 unsigned size, align;
36 AVStream *st;
37
38 avio_skip(s->pb, 4);
39
40 st = avformat_new_stream(s, NULL);
41 if (!st)
42 return AVERROR(ENOMEM);
43
44 size = avio_rl32(s->pb);
45 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
46 st->codecpar->codec_id = AV_CODEC_ID_ADPCM_PSX;
47 st->codecpar->sample_rate = avio_rl32(s->pb);
48 if (st->codecpar->sample_rate <= 0)
49 return AVERROR_INVALIDDATA;
50 st->codecpar->ch_layout.nb_channels = avio_rl32(s->pb);
51 if (st->codecpar->ch_layout.nb_channels <= 0 ||
52 st->codecpar->ch_layout.nb_channels > 8)
53 return AVERROR_INVALIDDATA;
54 st->duration = size / (16 * st->codecpar->ch_layout.nb_channels) * 28;
55 align = avio_rl32(s->pb);
56 if (align <= 0 || align > INT_MAX / st->codecpar->ch_layout.nb_channels)
57 return AVERROR_INVALIDDATA;
58 st->codecpar->block_align = align * st->codecpar->ch_layout.nb_channels;
59 avio_skip(s->pb, 0x800 - avio_tell(s->pb));
60 avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
61
62 return 0;
63 }
64
svag_read_packet(AVFormatContext * s,AVPacket * pkt)65 static int svag_read_packet(AVFormatContext *s, AVPacket *pkt)
66 {
67 AVCodecParameters *par = s->streams[0]->codecpar;
68
69 return av_get_packet(s->pb, pkt, par->block_align);
70 }
71
72 const AVInputFormat ff_svag_demuxer = {
73 .name = "svag",
74 .long_name = NULL_IF_CONFIG_SMALL("Konami PS2 SVAG"),
75 .read_probe = svag_probe,
76 .read_header = svag_read_header,
77 .read_packet = svag_read_packet,
78 .extensions = "svag",
79 };
80