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 
62  trim_right(line);
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 
220  ret = split_tag_value(&tag, &value, line);
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")) {
236  *size = parse_content_length(value);
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 remaining = 0, len;
332 
333  const int read_chunk = 2048;
334  av_init_packet(pkt);
335  pkt->data = NULL;
336  pkt->size = 0;
337  pkt->pos = avio_tell(s->pb);
338 
339  while ((ret = ffio_ensure_seekback(s->pb, read_chunk - remaining)) >= 0 && /* we may need to return as much as all we've read back to the buffer */
340  (ret = av_append_packet(s->pb, pkt, read_chunk - remaining)) >= 0) {
341  /* scan the new data */
342  char *start;
343 
344  len = ret + remaining;
345  start = pkt->data + pkt->size - len;
346  do {
347  if (!memcmp(start, mpjpeg->searchstr, mpjpeg->searchstr_len)) {
348  // got the boundary! rewind the stream
349  avio_seek(s->pb, -len, SEEK_CUR);
350  pkt->size -= len;
351  return pkt->size;
352  }
353  len--;
354  start++;
355  } while (len >= mpjpeg->searchstr_len);
356  remaining = len;
357  }
358 
359  /* error or EOF occurred */
360  if (ret == AVERROR_EOF) {
361  ret = pkt->size > 0 ? pkt->size : AVERROR_EOF;
362  } else {
363  av_packet_unref(pkt);
364  }
365  }
366 
367  return ret;
368 }
369 
370 #define OFFSET(x) offsetof(MPJPEGDemuxContext, x)
371 
372 #define DEC AV_OPT_FLAG_DECODING_PARAM
373 static const AVOption mpjpeg_options[] = {
374  { "strict_mime_boundary", "require MIME boundaries match", OFFSET(strict_mime_boundary), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, DEC },
375  { NULL }
376 };
377 
378 
380  .class_name = "MPJPEG demuxer",
381  .item_name = av_default_item_name,
382  .option = mpjpeg_options,
383  .version = LIBAVUTIL_VERSION_INT,
384 };
385 
387  .name = "mpjpeg",
388  .long_name = NULL_IF_CONFIG_SMALL("MIME multipart JPEG"),
389  .mime_type = "multipart/x-mixed-replace",
390  .extensions = "mjpg",
391  .priv_data_size = sizeof(MPJPEGDemuxContext),
396  .priv_class = &mpjpeg_demuxer_class,
398 };
399 
400 
#define NULL
Definition: coverity.c:32
const char const char void * val
Definition: avisynth_c.h:863
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AVOption.
Definition: opt.h:246
#define DEC
Definition: mpjpegdec.c:372
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1500
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:4926
static int get_line(AVIOContext *pb, char *line, int line_size)
Definition: mpjpegdec.c:52
static int read_chunk(AVFormatContext *s)
Definition: dhav.c:235
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3968
int size
Definition: avcodec.h:1481
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
static av_const int av_isspace(int c)
Locale-independent conversion of ASCII isspace.
Definition: avstring.h:222
static int split_tag_value(char **tag, char **value, char *line)
Definition: mpjpegdec.c:68
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1358
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:72
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
uint8_t
AVOptions.
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:108
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4499
uint8_t * data
Definition: avcodec.h:1480
uint32_t tag
Definition: movenc.c:1531
#define AVERROR_EOF
End of file.
Definition: error.h:55
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
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
static int mpjpeg_read_header(AVFormatContext *s)
Definition: mpjpegdec.c:130
#define av_log(a,...)
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:320
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
static int mpjpeg_read_close(AVFormatContext *s)
Definition: mpjpegdec.c:106
#define NULL_IF_CONFIG_SMALL(x)
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:3964
Definition: graph2dot.c:48
static const AVClass mpjpeg_demuxer_class
Definition: mpjpegdec.c:379
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:449
char * av_asprintf(const char *fmt,...)
Definition: avstring.c:113
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
int av_strcasecmp(const char *a, const char *b)
Locale-independent case-insensitive compare.
Definition: avstring.c:213
#define AV_OPT_SEARCH_CHILDREN
Search in possible children of the given object first.
Definition: opt.h:557
AVInputFormat ff_mpjpeg_demuxer
Definition: mpjpegdec.c:386
#define s(width, name)
Definition: cbs_vp9.c:257
int ff_get_line(AVIOContext *s, char *buf, int maxlen)
Read a whole line of text from AVIOContext.
Definition: aviobuf.c:811
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
Stream structure.
Definition: avformat.h:881
static int mpjpeg_read_probe(const AVProbeData *p)
Definition: mpjpegdec.c:114
static int parse_multipart_header(AVIOContext *pb, int *size, const char *expected_boundary, void *log_ctx)
Definition: mpjpegdec.c:171
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:467
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:251
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
Describe the class of an AVClass context structure.
Definition: log.h:67
#define OFFSET(x)
Definition: mpjpegdec.c:370
int error
contains the error code or 0 if no error happened
Definition: avio.h:245
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
#define SIZE_SPECIFIER
Definition: internal.h:262
#define flags(name, subs,...)
Definition: cbs_av1.c:561
static void trim_right(char *p)
Definition: mpjpegdec.c:40
int strict_mime_boundary
Definition: mpjpegdec.c:36
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
static const AVOption mpjpeg_options[]
Definition: mpjpegdec.c:373
int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size)
Ensures that the requested seekback buffer size will be available.
Definition: aviobuf.c:1054
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
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
Main libavformat public API header.
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:33
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:81
void av_init_packet(AVPacket *pkt)
Initialize optional fields of a packet with default values.
Definition: avpacket.c:33
static int mpjpeg_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mpjpegdec.c:293
int av_opt_get(void *obj, const char *name, int search_flags, uint8_t **out_val)
Definition: opt.c:761
int eof_reached
true if was unable to read due to error or eof
Definition: avio.h:239
int len
void * priv_data
Format private data.
Definition: avformat.h:1386
#define av_freep(p)
void INT64 start
Definition: avisynth_c.h:766
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
static char * mpjpeg_get_boundary(AVIOContext *pb)
Definition: mpjpegdec.c:249
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
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
static int parse_content_length(const char *value)
Definition: mpjpegdec.c:160
This structure stores compressed data.
Definition: avcodec.h:1457
char * av_strndup(const char *s, size_t len)
Duplicate a substring of a string.
Definition: mem.c:263