FFmpeg  4.4.4
smjpegdec.c
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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 {
38 
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 
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,
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);
95  ast->codecpar->sample_rate = avio_rb16(pb);
97  ast->codecpar->channels = avio_r8(pb);
98  ast->codecpar->codec_tag = avio_rl32(pb);
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 
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);
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);
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 
184  .name = "smjpeg",
185  .long_name = NULL_IF_CONFIG_SMALL("Loki SDL MJPEG"),
186  .priv_data_size = sizeof(SMJPEGContext),
190  .extensions = "mjpg",
192 };
Main libavformat public API header.
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
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
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:463
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:766
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:364
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:750
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:781
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:624
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
#define flags(name, subs,...)
Definition: cbs_av1.c:561
static int FUNC() comment(CodedBitstreamContext *ctx, RWContext *rw, JPEGRawComment *current)
#define s(width, name)
Definition: cbs_vp9.c:257
#define NULL
Definition: coverity.c:32
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:545
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4509
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that's been allocated with av_malloc() or another memory allocation functio...
Definition: dict.h:74
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
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR_EOF
End of file.
Definition: error.h:55
#define AVERROR(e)
Definition: error.h:43
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
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:4945
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:3131
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
version
Definition: libkvazaar.c:326
#define htype
internal header for RIFF based (de)muxers do NOT include this in end user applications
const AVCodecTag ff_codec_smjpeg_video_tags[]
Definition: smjpeg.c:31
const AVCodecTag ff_codec_smjpeg_audio_tags[]
Definition: smjpeg.c:36
SMJPEG common code.
#define SMJPEG_TXT
Definition: smjpeg.h:38
#define SMJPEG_DONE
Definition: smjpeg.h:34
#define SMJPEG_SND
Definition: smjpeg.h:36
#define SMJPEG_SNDD
Definition: smjpeg.h:37
#define SMJPEG_VIDD
Definition: smjpeg.h:40
#define SMJPEG_VID
Definition: smjpeg.h:39
#define SMJPEG_HEND
Definition: smjpeg.h:35
#define SMJPEG_MAGIC
Definition: smjpeg.h:32
AVInputFormat ff_smjpeg_demuxer
Definition: smjpegdec.c:183
static int smjpeg_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: smjpegdec.c:140
static int smjpeg_probe(const AVProbeData *p)
Definition: smjpegdec.c:39
static int smjpeg_read_header(AVFormatContext *s)
Definition: smjpegdec.c:46
unsigned int pos
Definition: spdifenc.c:412
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
int channels
Audio only.
Definition: codec_par.h:166
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:64
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int sample_rate
Audio only.
Definition: codec_par.h:170
Format I/O context.
Definition: avformat.h:1232
Bytestream IO Context.
Definition: avio.h:161
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
This structure stores compressed data.
Definition: packet.h:346
int stream_index
Definition: packet.h:371
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:362
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:389
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:922
int index
stream index in AVFormatContext
Definition: avformat.h:874
int audio_stream_index
Definition: smjpegdec.c:35
int video_stream_index
Definition: smjpegdec.c:36
#define avpriv_request_sample(...)
#define av_freep(p)
#define av_malloc(s)
#define av_log(a,...)
int64_t duration
Definition: movenc.c:64
AVPacket * pkt
Definition: movenc.c:59
int size