1 /*
2 * SMJPEG demuxer
3 * Copyright (c) 2011 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 /**
23 * @file
24 * This is a demuxer for Loki SDL Motion JPEG files
25 */
26
27 #include <inttypes.h>
28
29 #include "avformat.h"
30 #include "internal.h"
31 #include "riff.h"
32 #include "smjpeg.h"
33
34 typedef struct SMJPEGContext {
35 int audio_stream_index;
36 int video_stream_index;
37 } SMJPEGContext;
38
smjpeg_probe(const AVProbeData * p)39 static int smjpeg_probe(const AVProbeData *p)
40 {
41 if (!memcmp(p->buf, SMJPEG_MAGIC, 8))
42 return AVPROBE_SCORE_MAX;
43 return 0;
44 }
45
smjpeg_read_header(AVFormatContext * s)46 static int smjpeg_read_header(AVFormatContext *s)
47 {
48 SMJPEGContext *sc = s->priv_data;
49 AVStream *ast = NULL, *vst = NULL;
50 AVIOContext *pb = s->pb;
51 uint32_t version, htype, hlength, duration;
52 char *comment;
53
54 sc->audio_stream_index =
55 sc->video_stream_index = -1;
56
57 avio_skip(pb, 8); // magic
58 version = avio_rb32(pb);
59 if (version)
60 avpriv_request_sample(s, "Unknown version %"PRIu32, version);
61
62 duration = avio_rb32(pb); // in msec
63
64 while (!avio_feof(pb)) {
65 htype = avio_rl32(pb);
66 switch (htype) {
67 case SMJPEG_TXT:
68 hlength = avio_rb32(pb);
69 if (!hlength || hlength > 512)
70 return AVERROR_INVALIDDATA;
71 comment = av_malloc(hlength + 1);
72 if (!comment)
73 return AVERROR(ENOMEM);
74 if (avio_read(pb, comment, hlength) != hlength) {
75 av_freep(&comment);
76 av_log(s, AV_LOG_ERROR, "error when reading comment\n");
77 return AVERROR_INVALIDDATA;
78 }
79 comment[hlength] = 0;
80 av_dict_set(&s->metadata, "comment", comment,
81 AV_DICT_DONT_STRDUP_VAL);
82 break;
83 case SMJPEG_SND:
84 if (ast) {
85 avpriv_request_sample(s, "Multiple audio streams");
86 return AVERROR_PATCHWELCOME;
87 }
88 hlength = avio_rb32(pb);
89 if (hlength < 8)
90 return AVERROR_INVALIDDATA;
91 ast = avformat_new_stream(s, 0);
92 if (!ast)
93 return AVERROR(ENOMEM);
94 ast->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
95 ast->codecpar->sample_rate = avio_rb16(pb);
96 ast->codecpar->bits_per_coded_sample = avio_r8(pb);
97 ast->codecpar->channels = avio_r8(pb);
98 ast->codecpar->codec_tag = avio_rl32(pb);
99 ast->codecpar->codec_id = ff_codec_get_id(ff_codec_smjpeg_audio_tags,
100 ast->codecpar->codec_tag);
101 ast->duration = duration;
102 sc->audio_stream_index = ast->index;
103 avpriv_set_pts_info(ast, 32, 1, 1000);
104 avio_skip(pb, hlength - 8);
105 break;
106 case SMJPEG_VID:
107 if (vst) {
108 avpriv_request_sample(s, "Multiple video streams");
109 return AVERROR_INVALIDDATA;
110 }
111 hlength = avio_rb32(pb);
112 if (hlength < 12)
113 return AVERROR_INVALIDDATA;
114 vst = avformat_new_stream(s, 0);
115 if (!vst)
116 return AVERROR(ENOMEM);
117 vst->nb_frames = avio_rb32(pb);
118 vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
119 vst->codecpar->width = avio_rb16(pb);
120 vst->codecpar->height = avio_rb16(pb);
121 vst->codecpar->codec_tag = avio_rl32(pb);
122 vst->codecpar->codec_id = ff_codec_get_id(ff_codec_smjpeg_video_tags,
123 vst->codecpar->codec_tag);
124 vst->duration = duration;
125 sc->video_stream_index = vst->index;
126 avpriv_set_pts_info(vst, 32, 1, 1000);
127 avio_skip(pb, hlength - 12);
128 break;
129 case SMJPEG_HEND:
130 return 0;
131 default:
132 av_log(s, AV_LOG_ERROR, "unknown header %"PRIx32"\n", htype);
133 return AVERROR_INVALIDDATA;
134 }
135 }
136
137 return AVERROR_EOF;
138 }
139
smjpeg_read_packet(AVFormatContext * s,AVPacket * pkt)140 static int smjpeg_read_packet(AVFormatContext *s, AVPacket *pkt)
141 {
142 SMJPEGContext *sc = s->priv_data;
143 uint32_t dtype, size, timestamp;
144 int64_t pos;
145 int ret;
146
147 if (avio_feof(s->pb))
148 return AVERROR_EOF;
149 pos = avio_tell(s->pb);
150 dtype = avio_rl32(s->pb);
151 switch (dtype) {
152 case SMJPEG_SNDD:
153 if (sc->audio_stream_index < 0)
154 return AVERROR_INVALIDDATA;
155 timestamp = avio_rb32(s->pb);
156 size = avio_rb32(s->pb);
157 ret = av_get_packet(s->pb, pkt, size);
158 pkt->stream_index = sc->audio_stream_index;
159 pkt->pts = timestamp;
160 pkt->pos = pos;
161 break;
162 case SMJPEG_VIDD:
163 if (sc->video_stream_index < 0)
164 return AVERROR_INVALIDDATA;
165 timestamp = avio_rb32(s->pb);
166 size = avio_rb32(s->pb);
167 ret = av_get_packet(s->pb, pkt, size);
168 pkt->stream_index = sc->video_stream_index;
169 pkt->pts = timestamp;
170 pkt->pos = pos;
171 break;
172 case SMJPEG_DONE:
173 ret = AVERROR_EOF;
174 break;
175 default:
176 av_log(s, AV_LOG_ERROR, "unknown chunk %"PRIx32"\n", dtype);
177 ret = AVERROR_INVALIDDATA;
178 break;
179 }
180 return ret;
181 }
182
183 AVInputFormat ff_smjpeg_demuxer = {
184 .name = "smjpeg",
185 .long_name = NULL_IF_CONFIG_SMALL("Loki SDL MJPEG"),
186 .priv_data_size = sizeof(SMJPEGContext),
187 .read_probe = smjpeg_probe,
188 .read_header = smjpeg_read_header,
189 .read_packet = smjpeg_read_packet,
190 .extensions = "mjpg",
191 .flags = AVFMT_GENERIC_INDEX,
192 };
193