smjpegenc.c
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1 /*
2  * SMJPEG muxer
3  * Copyright (c) 2012 Paul B Mahol
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
27 #include "avformat.h"
28 #include "internal.h"
29 #include "riff.h"
30 #include "smjpeg.h"
31 
32 typedef struct SMJPEGMuxContext {
33  uint32_t duration;
35 
37 {
39  AVIOContext *pb = s->pb;
40  int n, tag;
41 
42  if (s->nb_streams > 2) {
43  av_log(s, AV_LOG_ERROR, "more than >2 streams are not supported\n");
44  return AVERROR(EINVAL);
45  }
46  avio_write(pb, SMJPEG_MAGIC, 8);
47  avio_wb32(pb, 0);
48  avio_wb32(pb, 0);
49 
50  while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX))) {
51  avio_wl32(pb, SMJPEG_TXT);
52  avio_wb32(pb, strlen(t->key) + strlen(t->value) + 3);
53  avio_write(pb, t->key, strlen(t->key));
54  avio_write(pb, " = ", 3);
55  avio_write(pb, t->value, strlen(t->value));
56  }
57 
58  for (n = 0; n < s->nb_streams; n++) {
59  AVStream *st = s->streams[n];
60  AVCodecContext *codec = st->codec;
61  if (codec->codec_type == AVMEDIA_TYPE_AUDIO) {
63  if (!tag) {
64  av_log(s, AV_LOG_ERROR, "unsupported audio codec\n");
65  return AVERROR(EINVAL);
66  }
67  avio_wl32(pb, SMJPEG_SND);
68  avio_wb32(pb, 8);
69  avio_wb16(pb, codec->sample_rate);
71  avio_w8(pb, codec->channels);
72  avio_wl32(pb, tag);
73  avpriv_set_pts_info(st, 32, 1, 1000);
74  } else if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {
76  if (!tag) {
77  av_log(s, AV_LOG_ERROR, "unsupported video codec\n");
78  return AVERROR(EINVAL);
79  }
80  avio_wl32(pb, SMJPEG_VID);
81  avio_wb32(pb, 12);
82  avio_wb32(pb, 0);
83  avio_wb16(pb, codec->width);
84  avio_wb16(pb, codec->height);
85  avio_wl32(pb, tag);
86  avpriv_set_pts_info(st, 32, 1, 1000);
87  }
88  }
89 
91  avio_flush(pb);
92 
93  return 0;
94 }
95 
97 {
98  SMJPEGMuxContext *smc = s->priv_data;
99  AVIOContext *pb = s->pb;
100  AVStream *st = s->streams[pkt->stream_index];
101  AVCodecContext *codec = st->codec;
102 
103  if (codec->codec_type == AVMEDIA_TYPE_AUDIO)
104  avio_wl32(pb, SMJPEG_SNDD);
105  else if (codec->codec_type == AVMEDIA_TYPE_VIDEO)
106  avio_wl32(pb, SMJPEG_VIDD);
107  else
108  return 0;
109 
110  avio_wb32(pb, pkt->pts);
111  avio_wb32(pb, pkt->size);
112  avio_write(pb, pkt->data, pkt->size);
113  avio_flush(pb);
114 
115  smc->duration = FFMAX(smc->duration, pkt->pts + pkt->duration);
116  return 0;
117 }
118 
120 {
121  SMJPEGMuxContext *smc = s->priv_data;
122  AVIOContext *pb = s->pb;
123  int64_t currentpos;
124 
125  if (pb->seekable) {
126  currentpos = avio_tell(pb);
127  avio_seek(pb, 12, SEEK_SET);
128  avio_wb32(pb, smc->duration);
129  avio_seek(pb, currentpos, SEEK_SET);
130  }
131 
132  avio_wl32(pb, SMJPEG_DONE);
133  avio_flush(pb);
134 
135  return 0;
136 }
137 
139  .name = "smjpeg",
140  .long_name = NULL_IF_CONFIG_SMALL("Loki SDL MJPEG"),
141  .priv_data_size = sizeof(SMJPEGMuxContext),
142  .audio_codec = CODEC_ID_PCM_S16LE,
143  .video_codec = CODEC_ID_MJPEG,
148  .codec_tag = (const AVCodecTag *const []){ ff_codec_smjpeg_video_tags, ff_codec_smjpeg_audio_tags, 0 },
149 };