1 /*
2 * AFC 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/channel_layout.h"
23 #include "avformat.h"
24 #include "internal.h"
25
26 typedef struct AFCDemuxContext {
27 int64_t data_end;
28 } AFCDemuxContext;
29
afc_read_header(AVFormatContext *s)30 static int afc_read_header(AVFormatContext *s)
31 {
32 AFCDemuxContext *c = s->priv_data;
33 AVStream *st;
34 int ret;
35
36 st = avformat_new_stream(s, NULL);
37 if (!st)
38 return AVERROR(ENOMEM);
39 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
40 st->codecpar->codec_id = AV_CODEC_ID_ADPCM_AFC;
41 st->codecpar->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_STEREO;
42
43 if ((ret = ff_alloc_extradata(st->codecpar, 1)) < 0)
44 return ret;
45 st->codecpar->extradata[0] = 8 * st->codecpar->ch_layout.nb_channels;
46
47 c->data_end = avio_rb32(s->pb) + 32LL;
48 st->duration = avio_rb32(s->pb);
49 st->codecpar->sample_rate = avio_rb16(s->pb);
50 avio_skip(s->pb, 22);
51 avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
52
53 return 0;
54 }
55
afc_read_packet(AVFormatContext *s, AVPacket *pkt)56 static int afc_read_packet(AVFormatContext *s, AVPacket *pkt)
57 {
58 AFCDemuxContext *c = s->priv_data;
59 int64_t size = c->data_end - avio_tell(s->pb);
60 int ret;
61
62 size = FFMIN(size, 18 * 128);
63 if (size <= 0)
64 return AVERROR_EOF;
65
66 ret = av_get_packet(s->pb, pkt, size);
67 pkt->stream_index = 0;
68 return ret;
69 }
70
71 const AVInputFormat ff_afc_demuxer = {
72 .name = "afc",
73 .long_name = NULL_IF_CONFIG_SMALL("AFC"),
74 .priv_data_size = sizeof(AFCDemuxContext),
75 .read_header = afc_read_header,
76 .read_packet = afc_read_packet,
77 .extensions = "afc",
78 .flags = AVFMT_NOBINSEARCH | AVFMT_NOGENSEARCH | AVFMT_NO_BYTE_SEEK,
79 };
80