aboutsummaryrefslogtreecommitdiffstats
path: root/libavformat/smjpegdec.c
blob: 02d0f29b99f19fb439cf04b53c041839f1bf97af (plain) (blame)
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
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
/*
 * SMJPEG demuxer
 * Copyright (c) 2011 Paul B Mahol
 *
 * 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
 * This is a demuxer for Loki SDL Motion JPEG files
 */

#include <inttypes.h>

#include "avformat.h"
#include "internal.h"
#include "riff.h"
#include "smjpeg.h"

typedef struct SMJPEGContext {
    int audio_stream_index;
    int video_stream_index;
} SMJPEGContext;

static int smjpeg_probe(const AVProbeData *p)
{
    if (!memcmp(p->buf, SMJPEG_MAGIC, 8))
        return AVPROBE_SCORE_MAX;
    return 0;
}

static int smjpeg_read_header(AVFormatContext *s)
{
    SMJPEGContext *sc = s->priv_data;
    AVStream *ast = NULL, *vst = NULL;
    AVIOContext *pb = s->pb;
    uint32_t version, htype, hlength, duration;
    char *comment;

    sc->audio_stream_index =
    sc->video_stream_index = -1;

    avio_skip(pb, 8); // magic
    version = avio_rb32(pb);
    if (version)
        avpriv_request_sample(s, "Unknown version %"PRIu32, version);

    duration = avio_rb32(pb); // in msec

    while (!avio_feof(pb)) {
        htype = avio_rl32(pb);
        switch (htype) {
        case SMJPEG_TXT:
            hlength = avio_rb32(pb);
            if (!hlength || hlength > 512)
                return AVERROR_INVALIDDATA;
            comment = av_malloc(hlength + 1);
            if (!comment)
                return AVERROR(ENOMEM);
            if (avio_read(pb, comment, hlength) != hlength) {
                av_freep(&comment);
                av_log(s, AV_LOG_ERROR, "error when reading comment\n");
                return AVERROR_INVALIDDATA;
            }
            comment[hlength] = 0;
            av_dict_set(&s->metadata, "comment", comment,
                        AV_DICT_DONT_STRDUP_VAL);
            break;
        case SMJPEG_SND:
            if (ast) {
                avpriv_request_sample(s, "Multiple audio streams");
                return AVERROR_PATCHWELCOME;
            }
            hlength = avio_rb32(pb);
            if (hlength < 8)
                return AVERROR_INVALIDDATA;
            ast = avformat_new_stream(s, 0);
            if (!ast)
                return AVERROR(ENOMEM);
            ast->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;
            ast->codecpar->sample_rate = avio_rb16(pb);
            ast->codecpar->bits_per_coded_sample = avio_r8(pb);
            ast->codecpar->ch_layout.nb_channels = avio_r8(pb);
            ast->codecpar->codec_tag   = avio_rl32(pb);
            ast->codecpar->codec_id    = ff_codec_get_id(ff_codec_smjpeg_audio_tags,
                                                         ast->codecpar->codec_tag);
            ast->duration           = duration;
            sc->audio_stream_index  = ast->index;
            avpriv_set_pts_info(ast, 32, 1, 1000);
            avio_skip(pb, hlength - 8);
            break;
        case SMJPEG_VID:
            if (vst) {
                avpriv_request_sample(s, "Multiple video streams");
                return AVERROR_INVALIDDATA;
            }
            hlength = avio_rb32(pb);
            if (hlength < 12)
                return AVERROR_INVALIDDATA;
            vst = avformat_new_stream(s, 0);
            if (!vst)
                return AVERROR(ENOMEM);
            vst->nb_frames            = avio_rb32(pb);
            vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
            vst->codecpar->width      = avio_rb16(pb);
            vst->codecpar->height     = avio_rb16(pb);
            vst->codecpar->codec_tag  = avio_rl32(pb);
            vst->codecpar->codec_id   = ff_codec_get_id(ff_codec_smjpeg_video_tags,
                                                        vst->codecpar->codec_tag);
            vst->duration          = duration;
            sc->video_stream_index = vst->index;
            avpriv_set_pts_info(vst, 32, 1, 1000);
            avio_skip(pb, hlength - 12);
            break;
        case SMJPEG_HEND:
            return 0;
        default:
            av_log(s, AV_LOG_ERROR, "unknown header %"PRIx32"\n", htype);
            return AVERROR_INVALIDDATA;
        }
    }

    return AVERROR_EOF;
}

static int smjpeg_read_packet(AVFormatContext *s, AVPacket *pkt)
{
    SMJPEGContext *sc = s->priv_data;
    uint32_t dtype, size, timestamp;
    int64_t pos;
    int ret;

    if (avio_feof(s->pb))
        return AVERROR_EOF;
    pos   = avio_tell(s->pb);
    dtype = avio_rl32(s->pb);
    switch (dtype) {
    case SMJPEG_SNDD:
        if (sc->audio_stream_index < 0)
            return AVERROR_INVALIDDATA;
        timestamp = avio_rb32(s->pb);
        size = avio_rb32(s->pb);
        ret = av_get_packet(s->pb, pkt, size);
        pkt->stream_index = sc->audio_stream_index;
        pkt->pts = timestamp;
        pkt->pos = pos;
        break;
    case SMJPEG_VIDD:
        if (sc->video_stream_index < 0)
            return AVERROR_INVALIDDATA;
        timestamp = avio_rb32(s->pb);
        size = avio_rb32(s->pb);
        ret = av_get_packet(s->pb, pkt, size);
        pkt->stream_index = sc->video_stream_index;
        pkt->pts = timestamp;
        pkt->pos = pos;
        break;
    case SMJPEG_DONE:
        ret = AVERROR_EOF;
        break;
    default:
        av_log(s, AV_LOG_ERROR, "unknown chunk %"PRIx32"\n", dtype);
        ret = AVERROR_INVALIDDATA;
        break;
    }
    return ret;
}

const AVInputFormat ff_smjpeg_demuxer = {
    .name           = "smjpeg",
    .long_name      = NULL_IF_CONFIG_SMALL("Loki SDL MJPEG"),
    .priv_data_size = sizeof(SMJPEGContext),
    .read_probe     = smjpeg_probe,
    .read_header    = smjpeg_read_header,
    .read_packet    = smjpeg_read_packet,
    .extensions     = "mjpg",
    .flags          = AVFMT_GENERIC_INDEX,
};