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 "smjpeg.h"
30 
31 typedef struct SMJPEGMuxContext {
32  uint32_t duration;
34 
36 {
38  AVIOContext *pb = s->pb;
39  int n, tag;
40 
41  if (s->nb_streams > 2) {
42  av_log(s, AV_LOG_ERROR, "more than >2 streams are not supported\n");
43  return AVERROR(EINVAL);
44  }
45  avio_write(pb, SMJPEG_MAGIC, 8);
46  avio_wb32(pb, 0);
47  avio_wb32(pb, 0);
48 
49  while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX))) {
50  avio_wl32(pb, SMJPEG_TXT);
51  avio_wb32(pb, strlen(t->key) + strlen(t->value) + 3);
52  avio_write(pb, t->key, strlen(t->key));
53  avio_write(pb, " = ", 3);
54  avio_write(pb, t->value, strlen(t->value));
55  }
56 
57  for (n = 0; n < s->nb_streams; n++) {
58  AVStream *st = s->streams[n];
59  AVCodecContext *codec = st->codec;
60  if (codec->codec_type == AVMEDIA_TYPE_AUDIO) {
62  if (!tag) {
63  av_log(s, AV_LOG_ERROR, "unsupported audio codec\n");
64  return AVERROR(EINVAL);
65  }
66  avio_wl32(pb, SMJPEG_SND);
67  avio_wb32(pb, 8);
68  avio_wb16(pb, codec->sample_rate);
70  avio_w8(pb, codec->channels);
71  avio_wl32(pb, tag);
72  avpriv_set_pts_info(st, 32, 1, 1000);
73  } else if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {
75  if (!tag) {
76  av_log(s, AV_LOG_ERROR, "unsupported video codec\n");
77  return AVERROR(EINVAL);
78  }
79  avio_wl32(pb, SMJPEG_VID);
80  avio_wb32(pb, 12);
81  avio_wb32(pb, 0);
82  avio_wb16(pb, codec->width);
83  avio_wb16(pb, codec->height);
84  avio_wl32(pb, tag);
85  avpriv_set_pts_info(st, 32, 1, 1000);
86  }
87  }
88 
90  avio_flush(pb);
91 
92  return 0;
93 }
94 
96 {
97  SMJPEGMuxContext *smc = s->priv_data;
98  AVIOContext *pb = s->pb;
99  AVStream *st = s->streams[pkt->stream_index];
100  AVCodecContext *codec = st->codec;
101 
102  if (codec->codec_type == AVMEDIA_TYPE_AUDIO)
103  avio_wl32(pb, SMJPEG_SNDD);
104  else if (codec->codec_type == AVMEDIA_TYPE_VIDEO)
105  avio_wl32(pb, SMJPEG_VIDD);
106  else
107  return 0;
108 
109  avio_wb32(pb, pkt->pts);
110  avio_wb32(pb, pkt->size);
111  avio_write(pb, pkt->data, pkt->size);
112  avio_flush(pb);
113 
114  smc->duration = FFMAX(smc->duration, pkt->pts + pkt->duration);
115  return 0;
116 }
117 
119 {
120  SMJPEGMuxContext *smc = s->priv_data;
121  AVIOContext *pb = s->pb;
122  int64_t currentpos;
123 
124  if (pb->seekable) {
125  currentpos = avio_tell(pb);
126  avio_seek(pb, 12, SEEK_SET);
127  avio_wb32(pb, smc->duration);
128  avio_seek(pb, currentpos, SEEK_SET);
129  }
130 
131  avio_wl32(pb, SMJPEG_DONE);
132 
133  return 0;
134 }
135 
137  .name = "smjpeg",
138  .long_name = NULL_IF_CONFIG_SMALL("Loki SDL MJPEG"),
139  .priv_data_size = sizeof(SMJPEGMuxContext),
140  .audio_codec = AV_CODEC_ID_PCM_S16LE,
141  .video_codec = AV_CODEC_ID_MJPEG,
146  .codec_tag = (const AVCodecTag *const []){ ff_codec_smjpeg_video_tags, ff_codec_smjpeg_audio_tags, 0 },
147 };
Bytestream IO Context.
Definition: avio.h:68
#define SMJPEG_DONE
Definition: smjpeg.h:34
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:3283
static int write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: assenc.c:58
static int smjpeg_write_trailer(AVFormatContext *s)
Definition: smjpegenc.c:118
int size
Definition: avcodec.h:916
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:186
#define SMJPEG_HEND
Definition: smjpeg.h:35
static int smjpeg_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: smjpegenc.c:95
unsigned int ff_codec_get_tag(const AVCodecTag *tags, enum AVCodecID id)
Definition: utils.c:2116
SMJPEG common code.
const AVCodecTag ff_codec_smjpeg_video_tags[]
Definition: smjpeg.c:31
AVDictionaryEntry * av_dict_get(AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags)
Get a dictionary entry with matching key.
Definition: dict.c:40
struct SMJPEGMuxContext SMJPEGMuxContext
Format I/O context.
Definition: avformat.h:828
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:260
AVStream ** streams
Definition: avformat.h:876
#define SMJPEG_SND
Definition: smjpeg.h:36
uint8_t * data
Definition: avcodec.h:915
static int flags
Definition: log.c:42
#define SMJPEG_VIDD
Definition: smjpeg.h:40
uint32_t tag
Definition: movenc.c:802
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:219
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:165
int duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:937
#define SMJPEG_TXT
Definition: smjpeg.h:38
static int write_trailer(AVFormatContext *s)
Definition: assenc.c:67
static float t
static int smjpeg_write_header(AVFormatContext *s)
Definition: smjpegenc.c:35
int av_get_bits_per_sample(enum AVCodecID codec_id)
Return codec bits per sample.
Definition: utils.c:1813
AVDictionary * metadata
Definition: avformat.h:972
#define SMJPEG_MAGIC
Definition: smjpeg.h:32
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:88
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:146
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:641
unsigned int nb_streams
A list of all streams in the file.
Definition: avformat.h:875
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:117
int void avio_flush(AVIOContext *s)
Definition: aviobuf.c:180
int width
picture width / height.
Definition: avcodec.h:1508
const char * name
Definition: avformat.h:376
Stream structure.
Definition: avformat.h:622
NULL
Definition: eval.c:52
enum AVMediaType codec_type
Definition: avcodec.h:1347
enum AVCodecID codec_id
Definition: avcodec.h:1350
int sample_rate
samples per second
Definition: avcodec.h:2104
AVIOContext * pb
I/O context.
Definition: avformat.h:861
void avio_w8(AVIOContext *s, int b)
Definition: aviobuf.c:144
main external API structure.
Definition: avcodec.h:1339
uint32_t duration
Definition: smjpegenc.c:32
#define SMJPEG_VID
Definition: smjpeg.h:39
void avio_wb16(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:342
Main libavformat public API header.
#define SMJPEG_SNDD
Definition: smjpeg.h:37
char * key
Definition: dict.h:75
const AVCodecTag ff_codec_smjpeg_audio_tags[]
Definition: smjpeg.c:36
char * value
Definition: dict.h:76
int channels
number of audio channels
Definition: avcodec.h:2105
void * priv_data
Format private data.
Definition: avformat.h:848
static void write_header(FFV1Context *f)
Definition: ffv1enc.c:380
void avio_wb32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:268
int stream_index
Definition: avcodec.h:917
AVOutputFormat ff_smjpeg_muxer
Definition: smjpegenc.c:136
This structure stores compressed data.
Definition: avcodec.h:898
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:908