1/*
2 * CRYO APC audio format demuxer
3 * Copyright (c) 2007 Anssi Hannula <anssi.hannula@gmail.com>
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 <string.h>
23#include "avformat.h"
24
25static int apc_probe(AVProbeData *p)
26{
27    if (!strncmp(p->buf, "CRYO_APC", 8))
28        return AVPROBE_SCORE_MAX;
29
30    return 0;
31}
32
33static int apc_read_header(AVFormatContext *s, AVFormatParameters *ap)
34{
35    ByteIOContext *pb = s->pb;
36    AVStream *st;
37
38    get_le32(pb); /* CRYO */
39    get_le32(pb); /* _APC */
40    get_le32(pb); /* 1.20 */
41
42    st = av_new_stream(s, 0);
43    if (!st)
44        return AVERROR(ENOMEM);
45
46    st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
47    st->codec->codec_id = CODEC_ID_ADPCM_IMA_WS;
48
49    get_le32(pb); /* number of samples */
50    st->codec->sample_rate = get_le32(pb);
51
52    st->codec->extradata_size = 2 * 4;
53    st->codec->extradata = av_malloc(st->codec->extradata_size +
54                                     FF_INPUT_BUFFER_PADDING_SIZE);
55    if (!st->codec->extradata)
56        return AVERROR(ENOMEM);
57
58    /* initial predictor values for adpcm decoder */
59    get_buffer(pb, st->codec->extradata, 2 * 4);
60
61    st->codec->channels = 1;
62    if (get_le32(pb))
63        st->codec->channels = 2;
64
65    st->codec->bits_per_coded_sample = 4;
66    st->codec->bit_rate = st->codec->bits_per_coded_sample * st->codec->channels
67                          * st->codec->sample_rate;
68    st->codec->block_align = 1;
69
70    return 0;
71}
72
73#define MAX_READ_SIZE 4096
74
75static int apc_read_packet(AVFormatContext *s, AVPacket *pkt)
76{
77    if (av_get_packet(s->pb, pkt, MAX_READ_SIZE) <= 0)
78        return AVERROR(EIO);
79    pkt->stream_index = 0;
80    return 0;
81}
82
83AVInputFormat apc_demuxer = {
84    "apc",
85    NULL_IF_CONFIG_SMALL("CRYO APC format"),
86    0,
87    apc_probe,
88    apc_read_header,
89    apc_read_packet,
90};
91