summaryrefslogtreecommitdiffstats
path: root/libavformat/adxdec.c
blob: a271e2afa80a7e8ca08878c5a373ac98ed7d220c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
/*
 * Copyright (c) 2011 Justin Ruggles
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * CRI ADX demuxer
 */

#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"

#define BLOCK_SIZE    18
#define BLOCK_SAMPLES 32

typedef struct ADXDemuxerContext {
    int header_size;
} ADXDemuxerContext;

static int adx_probe(AVProbeData *p)
{
    int offset;
    if (AV_RB16(p->buf) != 0x8000)
        return 0;
    offset = AV_RB16(&p->buf[2]);
    if (   offset < 8
        || offset > p->buf_size - 4
        || memcmp(p->buf + offset - 2, "(c)CRI", 6))
        return 0;
    return AVPROBE_SCORE_MAX * 3 / 4;
}

static int adx_read_packet(AVFormatContext *s, AVPacket *pkt)
{
    ADXDemuxerContext *c = s->priv_data;
    AVCodecParameters *par = s->streams[0]->codecpar;
    int ret, size;

    if (par->channels <= 0) {
        av_log(s, AV_LOG_ERROR, "invalid number of channels %d\n", par->channels);
        return AVERROR_INVALIDDATA;
    }

    size = BLOCK_SIZE * par->channels;

    pkt->pos = avio_tell(s->pb);
    pkt->stream_index = 0;

    ret = av_get_packet(s->pb, pkt, size);
    if (ret != size) {
        av_packet_unref(pkt);
        return ret < 0 ? ret : AVERROR(EIO);
    }
    if (AV_RB16(pkt->data) & 0x8000) {
        av_packet_unref(pkt);
        return AVERROR_EOF;
    }
    pkt->size     = size;
    pkt->duration = 1;
    pkt->pts      = (pkt->pos - c->header_size) / size;

    return 0;
}

static int adx_read_header(AVFormatContext *s)
{
    ADXDemuxerContext *c = s->priv_data;
    AVCodecParameters *par;

    AVStream *st = avformat_new_stream(s, NULL);
    if (!st)
        return AVERROR(ENOMEM);
    par = s->streams[0]->codecpar;

    if (avio_rb16(s->pb) != 0x8000)
        return AVERROR_INVALIDDATA;
    c->header_size = avio_rb16(s->pb) + 4;
    avio_seek(s->pb, -4, SEEK_CUR);

    if (ff_get_extradata(s, par, s->pb, c->header_size) < 0)
        return AVERROR(ENOMEM);

    if (par->extradata_size < 12) {
        av_log(s, AV_LOG_ERROR, "Invalid extradata size.\n");
        return AVERROR_INVALIDDATA;
    }
    par->channels    = AV_RB8 (par->extradata + 7);
    par->sample_rate = AV_RB32(par->extradata + 8);

    if (par->channels <= 0) {
        av_log(s, AV_LOG_ERROR, "invalid number of channels %d\n", par->channels);
        return AVERROR_INVALIDDATA;
    }

    if (par->sample_rate <= 0) {
        av_log(s, AV_LOG_ERROR, "Invalid sample rate %d\n", par->sample_rate);
        return AVERROR_INVALIDDATA;
    }

    par->codec_type  = AVMEDIA_TYPE_AUDIO;
    par->codec_id    = s->iformat->raw_codec_id;
    par->bit_rate    = (int64_t)par->sample_rate * par->channels * BLOCK_SIZE * 8LL / BLOCK_SAMPLES;

    avpriv_set_pts_info(st, 64, BLOCK_SAMPLES, par->sample_rate);

    return 0;
}

AVInputFormat ff_adx_demuxer = {
    .name           = "adx",
    .long_name      = NULL_IF_CONFIG_SMALL("CRI ADX"),
    .read_probe     = adx_probe,
    .priv_data_size = sizeof(ADXDemuxerContext),
    .read_header    = adx_read_header,
    .read_packet    = adx_read_packet,
    .extensions     = "adx",
    .raw_codec_id   = AV_CODEC_ID_ADPCM_ADX,
    .flags          = AVFMT_GENERIC_INDEX,
};
OpenPOWER on IntegriCloud