FFmpeg
mpjpegdec.c
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1 /*
2  * Multipart JPEG format
3  * Copyright (c) 2015 Luca Barbato
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 #include "libavutil/avstring.h"
23 #include "libavutil/opt.h"
24 
25 #include "avformat.h"
26 #include "internal.h"
27 #include "avio_internal.h"
28 
29 
30 
31 typedef struct MPJPEGDemuxContext {
32  const AVClass *class;
33  char *boundary;
34  char *searchstr;
38 
39 
40 static void trim_right(char *p)
41 {
42  char *end;
43 
44  if (!p || !*p)
45  return;
46 
47  end = p + strlen(p);
48  while (end > p && av_isspace(*(end-1)))
49  *(--end) = '\0';
50 }
51 
52 static int get_line(AVIOContext *pb, char *line, int line_size)
53 {
54  ff_get_line(pb, line, line_size);
55 
56  if (pb->error)
57  return pb->error;
58 
59  if (pb->eof_reached)
60  return AVERROR_EOF;
61 
63  return 0;
64 }
65 
66 
67 
68 static int split_tag_value(char **tag, char **value, char *line)
69 {
70  char *p = line;
71  int foundData = 0;
72 
73  *tag = NULL;
74  *value = NULL;
75 
76 
77  while (*p != '\0' && *p != ':') {
78  if (!av_isspace(*p)) {
79  foundData = 1;
80  }
81  p++;
82  }
83  if (*p != ':')
84  return foundData ? AVERROR_INVALIDDATA : 0;
85 
86  *p = '\0';
87  *tag = line;
88  trim_right(*tag);
89 
90  p++;
91 
92  while (av_isspace(*p))
93  p++;
94 
95  *value = p;
96  trim_right(*value);
97 
98  return 0;
99 }
100 
101 static int parse_multipart_header(AVIOContext *pb,
102  int* size,
103  const char* expected_boundary,
104  void *log_ctx);
105 
107 {
108  MPJPEGDemuxContext *mpjpeg = s->priv_data;
109  av_freep(&mpjpeg->boundary);
110  av_freep(&mpjpeg->searchstr);
111  return 0;
112 }
113 
114 static int mpjpeg_read_probe(const AVProbeData *p)
115 {
116  AVIOContext pb;
117  int ret = 0;
118  int size = 0;
119 
120  if (p->buf_size < 2 || p->buf[0] != '-' || p->buf[1] != '-')
121  return 0;
122 
123  ffio_init_context(&pb, p->buf, p->buf_size, 0, NULL, NULL, NULL, NULL);
124 
125  ret = (parse_multipart_header(&pb, &size, "--", NULL) >= 0) ? AVPROBE_SCORE_MAX : 0;
126 
127  return ret;
128 }
129 
131 {
132  AVStream *st;
133  char boundary[70 + 2 + 1] = {0};
134  int64_t pos = avio_tell(s->pb);
135  int ret;
136 
137  do {
138  ret = get_line(s->pb, boundary, sizeof(boundary));
139  if (ret < 0)
140  return ret;
141  } while (!boundary[0]);
142 
143  if (strncmp(boundary, "--", 2))
144  return AVERROR_INVALIDDATA;
145 
146  st = avformat_new_stream(s, NULL);
147  if (!st)
148  return AVERROR(ENOMEM);
149 
152 
153  avpriv_set_pts_info(st, 60, 1, 25);
154 
155  avio_seek(s->pb, pos, SEEK_SET);
156 
157  return 0;
158 }
159 
160 static int parse_content_length(const char *value)
161 {
162  long int val = strtol(value, NULL, 10);
163 
164  if (val == LONG_MIN || val == LONG_MAX)
165  return AVERROR(errno);
166  if (val > INT_MAX)
167  return AVERROR(ERANGE);
168  return val;
169 }
170 
172  int* size,
173  const char* expected_boundary,
174  void *log_ctx)
175 {
176  char line[128];
177  int found_content_type = 0;
178  int ret;
179 
180  *size = -1;
181 
182  // get the CRLF as empty string
183  ret = get_line(pb, line, sizeof(line));
184  if (ret < 0)
185  return ret;
186 
187  /* some implementation do not provide the required
188  * initial CRLF (see rfc1341 7.2.1)
189  */
190  while (!line[0]) {
191  ret = get_line(pb, line, sizeof(line));
192  if (ret < 0)
193  return ret;
194  }
195 
196  if (!av_strstart(line, expected_boundary, NULL)) {
197  if (log_ctx)
198  av_log(log_ctx,
199  AV_LOG_ERROR,
200  "Expected boundary '%s' not found, instead found a line of %"SIZE_SPECIFIER" bytes\n",
201  expected_boundary,
202  strlen(line));
203 
204  return AVERROR_INVALIDDATA;
205  }
206 
207  while (!pb->eof_reached) {
208  char *tag, *value;
209 
210  ret = get_line(pb, line, sizeof(line));
211  if (ret < 0) {
212  if (ret == AVERROR_EOF)
213  break;
214  return ret;
215  }
216 
217  if (line[0] == '\0')
218  break;
219 
221  if (ret < 0)
222  return ret;
223  if (value==NULL || tag==NULL)
224  break;
225 
226  if (!av_strcasecmp(tag, "Content-type")) {
227  if (av_strcasecmp(value, "image/jpeg")) {
228  if (log_ctx)
229  av_log(log_ctx, AV_LOG_ERROR,
230  "Unexpected %s : %s\n",
231  tag, value);
232  return AVERROR_INVALIDDATA;
233  } else
234  found_content_type = 1;
235  } else if (!av_strcasecmp(tag, "Content-Length")) {
237  if ( *size < 0 )
238  if (log_ctx)
239  av_log(log_ctx, AV_LOG_WARNING,
240  "Invalid Content-Length value : %s\n",
241  value);
242  }
243  }
244 
245  return found_content_type ? 0 : AVERROR_INVALIDDATA;
246 }
247 
248 
250 {
251  uint8_t *mime_type = NULL;
252  const char *start;
253  const char *end;
254  uint8_t *res = NULL;
255  int len;
256 
257  /* get MIME type, and skip to the first parameter */
258  av_opt_get(pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &mime_type);
259  start = mime_type;
260  while (start != NULL && *start != '\0') {
261  start = strchr(start, ';');
262  if (!start)
263  break;
264 
265  start = start+1;
266 
267  while (av_isspace(*start))
268  start++;
269 
270  if (av_stristart(start, "boundary=", &start)) {
271  end = strchr(start, ';');
272  if (end)
273  len = end - start - 1;
274  else
275  len = strlen(start);
276 
277  /* some endpoints may enclose the boundary
278  in Content-Type in quotes */
279  if ( len>2 && *start == '"' && start[len-1] == '"' ) {
280  start++;
281  len -= 2;
282  }
283  res = av_strndup(start, len);
284  break;
285  }
286  }
287 
288  av_freep(&mime_type);
289  return res;
290 }
291 
292 
294 {
295  int size;
296  int ret;
297 
298  MPJPEGDemuxContext *mpjpeg = s->priv_data;
299  if (mpjpeg->boundary == NULL) {
300  uint8_t* boundary = NULL;
301  if (mpjpeg->strict_mime_boundary) {
302  boundary = mpjpeg_get_boundary(s->pb);
303  }
304  if (boundary != NULL) {
305  mpjpeg->boundary = av_asprintf("--%s", boundary);
306  mpjpeg->searchstr = av_asprintf("\r\n--%s\r\n", boundary);
307  av_freep(&boundary);
308  } else {
309  mpjpeg->boundary = av_strdup("--");
310  mpjpeg->searchstr = av_strdup("\r\n--");
311  }
312  if (!mpjpeg->boundary || !mpjpeg->searchstr) {
313  av_freep(&mpjpeg->boundary);
314  av_freep(&mpjpeg->searchstr);
315  return AVERROR(ENOMEM);
316  }
317  mpjpeg->searchstr_len = strlen(mpjpeg->searchstr);
318  }
319 
320  ret = parse_multipart_header(s->pb, &size, mpjpeg->boundary, s);
321 
322 
323  if (ret < 0)
324  return ret;
325 
326  if (size > 0) {
327  /* size has been provided to us in MIME header */
328  ret = av_get_packet(s->pb, pkt, size);
329  } else {
330  /* no size was given -- we read until the next boundary or end-of-file */
331  int len;
332 
333  const int read_chunk = 2048;
334 
335  pkt->pos = avio_tell(s->pb);
336 
337  while ((ret = ffio_ensure_seekback(s->pb, read_chunk)) >= 0 && /* we may need to return as much as all we've read back to the buffer */
338  (ret = av_append_packet(s->pb, pkt, read_chunk)) >= 0) {
339  /* scan the new data */
340  char *start;
341 
342  len = ret;
343  start = pkt->data + pkt->size - len;
344  do {
345  if (!memcmp(start, mpjpeg->searchstr, mpjpeg->searchstr_len)) {
346  // got the boundary! rewind the stream
347  avio_seek(s->pb, -len, SEEK_CUR);
348  pkt->size -= len;
349  return pkt->size;
350  }
351  len--;
352  start++;
353  } while (len >= mpjpeg->searchstr_len);
354  avio_seek(s->pb, -len, SEEK_CUR);
355  pkt->size -= len;
356  }
357 
358  /* error or EOF occurred */
359  if (ret == AVERROR_EOF) {
360  ret = pkt->size > 0 ? pkt->size : AVERROR_EOF;
361  }
362  }
363 
364  return ret;
365 }
366 
367 #define OFFSET(x) offsetof(MPJPEGDemuxContext, x)
368 
369 #define DEC AV_OPT_FLAG_DECODING_PARAM
370 static const AVOption mpjpeg_options[] = {
371  { "strict_mime_boundary", "require MIME boundaries match", OFFSET(strict_mime_boundary), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, DEC },
372  { NULL }
373 };
374 
375 
377  .class_name = "MPJPEG demuxer",
378  .item_name = av_default_item_name,
379  .option = mpjpeg_options,
380  .version = LIBAVUTIL_VERSION_INT,
381 };
382 
384  .name = "mpjpeg",
385  .long_name = NULL_IF_CONFIG_SMALL("MIME multipart JPEG"),
386  .mime_type = "multipart/x-mixed-replace",
387  .extensions = "mjpg",
388  .priv_data_size = sizeof(MPJPEGDemuxContext),
393  .priv_class = &mpjpeg_demuxer_class,
395 };
396 
397 
MPJPEGDemuxContext::boundary
char * boundary
Definition: mpjpegdec.c:33
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
AVERROR
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
opt.h
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4375
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:467
av_asprintf
char * av_asprintf(const char *fmt,...)
Definition: avstring.c:113
av_strcasecmp
int av_strcasecmp(const char *a, const char *b)
Locale-independent case-insensitive compare.
Definition: avstring.c:215
av_isspace
static av_const int av_isspace(int c)
Locale-independent conversion of ASCII isspace.
Definition: avstring.h:227
AVPacket::data
uint8_t * data
Definition: packet.h:373
AVOption
AVOption.
Definition: opt.h:247
AVIOContext::error
int error
contains the error code or 0 if no error happened
Definition: avio.h:245
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:449
DEC
#define DEC
Definition: mpjpegdec.c:369
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
read_close
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:141
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:538
val
static double val(void *priv, double ch)
Definition: aeval.c:75
OFFSET
#define OFFSET(x)
Definition: mpjpegdec.c:367
get_line
static int get_line(AVIOContext *pb, char *line, int line_size)
Definition: mpjpegdec.c:52
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:626
mpjpeg_get_boundary
static char * mpjpeg_get_boundary(AVIOContext *pb)
Definition: mpjpegdec.c:249
s
#define s(width, name)
Definition: cbs_vp9.c:257
trim_right
static void trim_right(char *p)
Definition: mpjpegdec.c:40
ff_mpjpeg_demuxer
const AVInputFormat ff_mpjpeg_demuxer
Definition: mpjpegdec.c:383
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:631
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
read_chunk
static int read_chunk(AVFormatContext *s)
Definition: dhav.c:166
av_stristart
int av_stristart(const char *str, const char *pfx, const char **ptr)
Return non-zero if pfx is a prefix of str independent of case.
Definition: avstring.c:45
parse_multipart_header
static int parse_multipart_header(AVIOContext *pb, int *size, const char *expected_boundary, void *log_ctx)
Definition: mpjpegdec.c:171
MPJPEGDemuxContext::searchstr
char * searchstr
Definition: mpjpegdec.c:34
AVFormatContext
Format I/O context.
Definition: avformat.h:1107
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:994
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
MPJPEGDemuxContext::searchstr_len
int searchstr_len
Definition: mpjpegdec.c:35
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
mpjpeg_demuxer_class
static const AVClass mpjpeg_demuxer_class
Definition: mpjpegdec.c:376
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
ffio_init_context
int ffio_init_context(AVIOContext *s, unsigned char *buffer, int buffer_size, int write_flag, void *opaque, int(*read_packet)(void *opaque, uint8_t *buf, int buf_size), int(*write_packet)(void *opaque, uint8_t *buf, int buf_size), int64_t(*seek)(void *opaque, int64_t offset, int whence))
Definition: aviobuf.c:78
AVPacket::size
int size
Definition: packet.h:374
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:116
MPJPEGDemuxContext::strict_mime_boundary
int strict_mime_boundary
Definition: mpjpegdec.c:36
avpriv_set_pts_info
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:4800
size
int size
Definition: twinvq_data.h:10344
AV_OPT_SEARCH_CHILDREN
#define AV_OPT_SEARCH_CHILDREN
Search in possible children of the given object first.
Definition: opt.h:559
ffio_ensure_seekback
int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size)
Ensures that the requested seekback buffer size will be available.
Definition: aviobuf.c:981
mpjpeg_read_probe
static int mpjpeg_read_probe(const AVProbeData *p)
Definition: mpjpegdec.c:114
line
Definition: graph2dot.c:48
mpjpeg_read_close
static int mpjpeg_read_close(AVFormatContext *s)
Definition: mpjpegdec.c:106
mpjpeg_read_packet
static int mpjpeg_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mpjpegdec.c:293
mpjpeg_options
static const AVOption mpjpeg_options[]
Definition: mpjpegdec.c:370
av_strstart
int av_strstart(const char *str, const char *pfx, const char **ptr)
Return non-zero if pfx is a prefix of str.
Definition: avstring.c:34
MPJPEGDemuxContext
Definition: mpjpegdec.c:31
AV_CODEC_ID_MJPEG
@ AV_CODEC_ID_MJPEG
Definition: codec_id.h:57
avio_internal.h
value
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default value
Definition: writing_filters.txt:86
ff_get_line
int ff_get_line(AVIOContext *s, char *buf, int maxlen)
Read a whole line of text from AVIOContext.
Definition: aviobuf.c:772
len
int len
Definition: vorbis_enc_data.h:426
split_tag_value
static int split_tag_value(char **tag, char **value, char *line)
Definition: mpjpegdec.c:68
parse_content_length
static int parse_content_length(const char *value)
Definition: mpjpegdec.c:160
av_get_packet
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:282
tag
uint32_t tag
Definition: movenc.c:1594
ret
ret
Definition: filter_design.txt:187
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVStream
Stream structure.
Definition: avformat.h:847
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:243
AVClass::class_name
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:71
av_append_packet
int av_append_packet(AVIOContext *s, AVPacket *pkt, int size)
Read data and append it to the current content of the AVPacket.
Definition: utils.c:298
pos
unsigned int pos
Definition: spdifenc.c:412
avformat.h
SIZE_SPECIFIER
#define SIZE_SPECIFIER
Definition: internal.h:192
AVIOContext::eof_reached
int eof_reached
true if was unable to read due to error or eof
Definition: avio.h:239
mpjpeg_read_header
static int mpjpeg_read_header(AVFormatContext *s)
Definition: mpjpegdec.c:130
av_strdup
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:259
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVPacket
This structure stores compressed data.
Definition: packet.h:350
AV_OPT_TYPE_BOOL
@ AV_OPT_TYPE_BOOL
Definition: opt.h:241
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:393
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
av_opt_get
int av_opt_get(void *obj, const char *name, int search_flags, uint8_t **out_val)
Definition: opt.c:779
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
avstring.h
av_strndup
char * av_strndup(const char *s, size_t len)
Duplicate a substring of a string.
Definition: mem.c:271
line
The official guide to swscale for confused that consecutive non overlapping rectangles of slice_bottom special converter These generally are unscaled converters of common like for each output line the vertical scaler pulls lines from a ring buffer When the ring buffer does not contain the wanted line
Definition: swscale.txt:40