Go to the documentation of this file.
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
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  */
22 /**
23  * @file
24  * This is a demuxer for Loki SDL Motion JPEG files
25  */
27 #include <inttypes.h>
29 #include "avformat.h"
30 #include "internal.h"
31 #include "riff.h"
32 #include "smjpeg.h"
34 typedef struct SMJPEGContext {
39 static int smjpeg_probe(const AVProbeData *p)
40 {
41  if (!memcmp(p->buf, SMJPEG_MAGIC, 8))
43  return 0;
44 }
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;
54  avio_skip(pb, 8); // magic
55  version = avio_rb32(pb);
56  if (version)
57  avpriv_request_sample(s, "Unknown version %"PRIu32, version);
59  duration = avio_rb32(pb); // in msec
61  while (!avio_feof(pb)) {
62  htype = avio_rl32(pb);
63  switch (htype) {
64  case SMJPEG_TXT:
65  hlength = avio_rb32(pb);
66  if (!hlength || hlength > 512)
68  comment = av_malloc(hlength + 1);
69  if (!comment)
70  return AVERROR(ENOMEM);
71  if (avio_read(pb, comment, hlength) != hlength) {
72  av_freep(&comment);
73  av_log(s, AV_LOG_ERROR, "error when reading comment\n");
75  }
76  comment[hlength] = 0;
77  av_dict_set(&s->metadata, "comment", comment,
79  break;
80  case SMJPEG_SND:
81  if (ast) {
82  avpriv_request_sample(s, "Multiple audio streams");
84  }
85  hlength = avio_rb32(pb);
86  if (hlength < 8)
88  ast = avformat_new_stream(s, 0);
89  if (!ast)
90  return AVERROR(ENOMEM);
92  ast->codecpar->sample_rate = avio_rb16(pb);
94  ast->codecpar->channels = avio_r8(pb);
95  ast->codecpar->codec_tag = avio_rl32(pb);
97  ast->codecpar->codec_tag);
98  ast->duration = duration;
99  sc->audio_stream_index = ast->index;
100  avpriv_set_pts_info(ast, 32, 1, 1000);
101  avio_skip(pb, hlength - 8);
102  break;
103  case SMJPEG_VID:
104  if (vst) {
105  avpriv_request_sample(s, "Multiple video streams");
107  }
108  hlength = avio_rb32(pb);
109  if (hlength < 12)
111  vst = avformat_new_stream(s, 0);
112  if (!vst)
113  return AVERROR(ENOMEM);
114  vst->nb_frames = avio_rb32(pb);
115  vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
116  vst->codecpar->width = avio_rb16(pb);
117  vst->codecpar->height = avio_rb16(pb);
118  vst->codecpar->codec_tag = avio_rl32(pb);
119  vst->codecpar->codec_id = ff_codec_get_id(ff_codec_smjpeg_video_tags,
120  vst->codecpar->codec_tag);
121  vst->duration = duration;
122  sc->video_stream_index = vst->index;
123  avpriv_set_pts_info(vst, 32, 1, 1000);
124  avio_skip(pb, hlength - 12);
125  break;
126  case SMJPEG_HEND:
127  return 0;
128  default:
129  av_log(s, AV_LOG_ERROR, "unknown header %"PRIx32"\n", htype);
131  }
132  }
134  return AVERROR_EOF;
135 }
138 {
139  SMJPEGContext *sc = s->priv_data;
140  uint32_t dtype, size, timestamp;
141  int64_t pos;
142  int ret;
144  if (avio_feof(s->pb))
145  return AVERROR_EOF;
146  pos = avio_tell(s->pb);
147  dtype = avio_rl32(s->pb);
148  switch (dtype) {
149  case SMJPEG_SNDD:
150  timestamp = avio_rb32(s->pb);
151  size = avio_rb32(s->pb);
152  ret = av_get_packet(s->pb, pkt, size);
153  pkt->stream_index = sc->audio_stream_index;
154  pkt->pts = timestamp;
155  pkt->pos = pos;
156  break;
157  case SMJPEG_VIDD:
158  timestamp = avio_rb32(s->pb);
159  size = avio_rb32(s->pb);
160  ret = av_get_packet(s->pb, pkt, size);
161  pkt->stream_index = sc->video_stream_index;
162  pkt->pts = timestamp;
163  pkt->pos = pos;
164  break;
165  case SMJPEG_DONE:
166  ret = AVERROR_EOF;
167  break;
168  default:
169  av_log(s, AV_LOG_ERROR, "unknown chunk %"PRIx32"\n", dtype);
171  break;
172  }
173  return ret;
174 }
177  .name = "smjpeg",
178  .long_name = NULL_IF_CONFIG_SMALL("Loki SDL MJPEG"),
179  .priv_data_size = sizeof(SMJPEGContext),
183  .extensions = "mjpg",
185 };
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:161
Invalid data found when processing input.
Definition: error.h:59
Definition: smjpeg.h:34
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:3124
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1497
AVInputFormat ff_smjpeg_demuxer
Definition: smjpegdec.c:176
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:4882
#define avpriv_request_sample(...)
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3953
int index
stream index in AVFormatContext
Definition: avformat.h:882
Definition: smjpeg.h:35
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
int version
Definition: avisynth_c.h:858
SMJPEG common code.
static AVPacket pkt
const AVCodecTag ff_codec_smjpeg_video_tags[]
Definition: smjpeg.c:31
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:786
Format I/O context.
Definition: avformat.h:1358
#define av_malloc(s)
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:801
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4455
int64_t duration
Definition: movenc.c:63
#define SMJPEG_SND
Definition: smjpeg.h:36
static int smjpeg_read_header(AVFormatContext *s)
Definition: smjpegdec.c:46
Definition: smjpeg.h:40
End of file.
Definition: error.h:55
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:310
ptrdiff_t size
Definition: opengl_enc.c:100
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
int video_stream_index
Definition: smjpegdec.c:36
#define av_log(a,...)
#define SMJPEG_TXT
Definition: smjpeg.h:38
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:648
static int FUNC() comment(CodedBitstreamContext *ctx, RWContext *rw, JPEGRawComment *current)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1598
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:770
Definition: smjpeg.h:32
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3949
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:639
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
Take ownership of a value that&#39;s been allocated with av_malloc() or another memory allocation functio...
Definition: dict.h:76
internal header for RIFF based (de)muxers do NOT include this in end user applications ...
#define s(width, name)
Definition: cbs_vp9.c:257
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
Stream structure.
Definition: avformat.h:881
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
int audio_stream_index
Definition: smjpegdec.c:35
#define SMJPEG_VID
Definition: smjpeg.h:39
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
Use generic index building code.
Definition: avformat.h:468
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
static int smjpeg_probe(const AVProbeData *p)
Definition: smjpegdec.c:39
#define flags(name, subs,...)
Definition: cbs_av1.c:561
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:930
int sample_rate
Audio only.
Definition: avcodec.h:4063
maximum score
Definition: avformat.h:458
Main libavformat public API header.
Definition: smjpeg.h:37
static int smjpeg_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: smjpegdec.c:137
const AVCodecTag ff_codec_smjpeg_audio_tags[]
Definition: smjpeg.c:36
void * priv_data
Format private data.
Definition: avformat.h:1386
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: avcodec.h:3995
int channels
Audio only.
Definition: avcodec.h:4059
#define av_freep(p)
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:358
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: avcodec.h:3957
int stream_index
Definition: avcodec.h:1479
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
This structure stores compressed data.
Definition: avcodec.h:1454
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1470