FFmpeg: libavformat/mpjpegdec.c Source File

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;
35   int searchstr_len;
36   int strict_mime_boundary;
37 } MPJPEGDemuxContext;
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円';
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円' && *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円';
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 
106  static int mpjpeg_read_close(AVFormatContext *s)
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(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  pb = avio_alloc_context(p->buf, p->buf_size, 0, NULL, NULL, NULL, NULL);
124  if (!pb)
125  return 0;
126 
127  ret = (parse_multipart_header(pb, &size, "--", NULL) > 0) ? AVPROBE_SCORE_MAX : 0;
128 
129  av_free(pb);
130 
131  return ret;
132 }
133 
134  static int mpjpeg_read_header(AVFormatContext *s)
135 {
136  AVStream *st;
137  char boundary[70 + 2 + 1] = {0};
138  int64_t pos = avio_tell(s->pb);
139  int ret;
140 
141  do {
142  ret = get_line(s->pb, boundary, sizeof(boundary));
143  if (ret < 0)
144  return ret;
145  } while (!boundary[0]);
146 
147  if (strncmp(boundary, "--", 2))
148  return AVERROR_INVALIDDATA;
149 
150  st = avformat_new_stream(s, NULL);
151  if (!st)
152  return AVERROR(ENOMEM);
153 
154  st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
155  st->codec->codec_id = AV_CODEC_ID_MJPEG;
156 
157  avpriv_set_pts_info(st, 60, 1, 25);
158 
159  avio_seek(s->pb, pos, SEEK_SET);
160 
161  return 0;
162 }
163 
164  static int parse_content_length(const char *value)
165 {
166  long int val = strtol(value, NULL, 10);
167 
168  if (val == LONG_MIN || val == LONG_MAX)
169  return AVERROR(errno);
170  if (val > INT_MAX)
171  return AVERROR(ERANGE);
172  return val;
173 }
174 
175  static int parse_multipart_header(AVIOContext *pb,
176  int* size,
177  const char* expected_boundary,
178  void *log_ctx)
179 {
180  char line[128];
181  int found_content_type = 0;
182  int ret;
183 
184  *size = -1;
185 
186  // get the CRLF as empty string
187  ret = get_line(pb, line, sizeof(line));
188  if (ret < 0)
189  return ret;
190 
191  /* some implementation do not provide the required
192  * initial CRLF (see rfc1341 7.2.1)
193  */
194  while (!line[0]) {
195  ret = get_line(pb, line, sizeof(line));
196  if (ret < 0)
197  return ret;
198  }
199 
200  if (!av_strstart(line, expected_boundary, NULL)) {
201  if (log_ctx)
202  av_log(log_ctx,
203  AV_LOG_ERROR,
204  "Expected boundary '%s' not found, instead found a line of %zu bytes\n",
205  expected_boundary,
206  strlen(line));
207 
208  return AVERROR_INVALIDDATA;
209  }
210 
211  while (!pb->eof_reached) {
212  char *tag, *value;
213 
214  ret = get_line(pb, line, sizeof(line));
215  if (ret < 0) {
216  if (ret == AVERROR_EOF)
217  break;
218  return ret;
219  }
220 
221  if (line[0] == '0円')
222  break;
223 
224  ret = split_tag_value(&tag, &value, line);
225  if (ret < 0)
226  return ret;
227  if (value==NULL || tag==NULL)
228  break;
229 
230  if (!av_strcasecmp(tag, "Content-type")) {
231  if (av_strcasecmp(value, "image/jpeg")) {
232  if (log_ctx)
233  av_log(log_ctx, AV_LOG_ERROR,
234  "Unexpected %s : %s\n",
235  tag, value);
236  return AVERROR_INVALIDDATA;
237  } else
238  found_content_type = 1;
239  } else if (!av_strcasecmp(tag, "Content-Length")) {
240  *size = parse_content_length(value);
241  if ( *size < 0 )
242  if (log_ctx)
243  av_log(log_ctx, AV_LOG_WARNING,
244  "Invalid Content-Length value : %s\n",
245  value);
246  }
247  }
248 
249  return found_content_type ? 0 : AVERROR_INVALIDDATA;
250 }
251 
252 
253  static char* mpjpeg_get_boundary(AVIOContext* pb)
254 {
255  uint8_t *mime_type = NULL;
256  const char *start;
257  const char *end;
258  uint8_t *res = NULL;
259  int len;
260 
261  /* get MIME type, and skip to the first parameter */
262  av_opt_get(pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &mime_type);
263  start = mime_type;
264  while (start != NULL && *start != '0円') {
265  start = strchr(start, ';');
266  if (!start)
267  break;
268 
269  start = start+1;
270 
271  while (av_isspace(*start))
272  start++;
273 
274  if (!av_stristart(start, "boundary=", &start)) {
275  end = strchr(start, ';');
276  if (end)
277  len = end - start - 1;
278  else
279  len = strlen(start);
280 
281  /* some endpoints may enclose the boundary
282  in Content-Type in quotes */
283  if ( len>2 && *start == '"' && start[len-1] == '"' ) {
284  start++;
285  len -= 2;
286  }
287  res = av_strndup(start, len);
288  break;
289  }
290  }
291 
292  av_freep(&mime_type);
293  return res;
294 }
295 
296 
297  static int mpjpeg_read_packet(AVFormatContext *s, AVPacket *pkt)
298 {
299  int size;
300  int ret;
301 
302  MPJPEGDemuxContext *mpjpeg = s->priv_data;
303  if (mpjpeg->boundary == NULL) {
304  uint8_t* boundary = NULL;
305  if (mpjpeg->strict_mime_boundary) {
306  boundary = mpjpeg_get_boundary(s->pb);
307  }
308  if (boundary != NULL) {
309  mpjpeg->boundary = boundary;
310  mpjpeg->searchstr = av_asprintf( "\r\n%s\r\n", boundary );
311  } else {
312  mpjpeg->boundary = av_strdup("--");
313  mpjpeg->searchstr = av_strdup("\r\n--");
314  }
315  if (!mpjpeg->boundary || !mpjpeg->searchstr) {
316  av_freep(&mpjpeg->boundary);
317  av_freep(&mpjpeg->searchstr);
318  return AVERROR(ENOMEM);
319  }
320  mpjpeg->searchstr_len = strlen(mpjpeg->searchstr);
321  }
322 
323  ret = parse_multipart_header(s->pb, &size, mpjpeg->boundary, s);
324 
325 
326  if (ret < 0)
327  return ret;
328 
329  if (size > 0) {
330  /* size has been provided to us in MIME header */
331  ret = av_get_packet(s->pb, pkt, size);
332  } else {
333  /* no size was given -- we read until the next boundary or end-of-file */
334  int remaining = 0, len;
335 
336  const int read_chunk = 2048;
337  av_init_packet(pkt);
338  pkt->data = NULL;
339  pkt->size = 0;
340  pkt->pos = avio_tell(s->pb);
341 
342  /* we may need to return as much as all we've read back to the buffer */
343  ffio_ensure_seekback(s->pb, read_chunk);
344 
345  while ((ret = av_append_packet(s->pb, pkt, read_chunk - remaining)) >= 0) {
346  /* scan the new data */
347  char *start;
348 
349  len = ret + remaining;
350  start = pkt->data + pkt->size - len;
351  do {
352  if (!memcmp(start, mpjpeg->searchstr, mpjpeg->searchstr_len)) {
353  // got the boundary! rewind the stream
354  avio_seek(s->pb, -len, SEEK_CUR);
355  pkt->size -= len;
356  return pkt->size;
357  }
358  len--;
359  start++;
360  } while (len >= mpjpeg->searchstr_len);
361  remaining = len;
362  }
363 
364  /* error or EOF occurred */
365  if (ret == AVERROR_EOF) {
366  ret = pkt->size > 0 ? pkt->size : AVERROR_EOF;
367  } else {
368  av_packet_unref(pkt);
369  }
370  }
371 
372  return ret;
373 }
374 
375  #define OFFSET(x) offsetof(MPJPEGDemuxContext, x)
376 
377  #define DEC AV_OPT_FLAG_DECODING_PARAM
378  const AVOption mpjpeg_options[] = {
379  { "strict_mime_boundary", "require MIME boundaries match", OFFSET(strict_mime_boundary), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, DEC },
380  { NULL }
381 };
382 
383 
384  static const AVClass mpjpeg_demuxer_class = {
385  .class_name = "MPJPEG demuxer",
386  .item_name = av_default_item_name,
387  .option = mpjpeg_options,
388  .version = LIBAVUTIL_VERSION_INT,
389 };
390 
391  AVInputFormat ff_mpjpeg_demuxer = {
392  .name = "mpjpeg",
393  .long_name = NULL_IF_CONFIG_SMALL("MIME multipart JPEG"),
394  .mime_type = "multipart/x-mixed-replace",
395  .extensions = "mjpg",
396  .priv_data_size = sizeof(MPJPEGDemuxContext),
397  .read_probe = mpjpeg_read_probe,
398  .read_header = mpjpeg_read_header,
399  .read_packet = mpjpeg_read_packet,
400  .read_close = mpjpeg_read_close,
401  .priv_class = &mpjpeg_demuxer_class
402 };
403 
404 
NULL
#define NULL
Definition: coverity.c:32
val
const char const char void * val
Definition: avisynth_c.h:634
s
const char * s
Definition: avisynth_c.h:631
AVIOContext
Bytestream IO Context.
Definition: avio.h:111
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AVOption
AVOption.
Definition: opt.h:245
DEC
#define DEC
Definition: mpjpegdec.c:377
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:70
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1487
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:4149
get_line
static int get_line(AVIOContext *pb, char *line, int line_size)
Definition: mpjpegdec.c:52
AVPacket::size
int size
Definition: avcodec.h:1468
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:208
av_isspace
static av_const int av_isspace(int c)
Locale-independent conversion of ASCII isspace.
Definition: avstring.h:222
split_tag_value
static int split_tag_value(char **tag, char **value, char *line)
Definition: mpjpegdec.c:68
pkt
static AVPacket pkt
Definition: demuxing_decoding.c:54
AVFormatContext
Format I/O context.
Definition: avformat.h:1314
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:72
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
uint8_t
uint8_t
Definition: audio_convert.c:194
opt.h
AVOptions.
end
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3805
avio_internal.h
AVPacket::data
uint8_t * data
Definition: avcodec.h:1467
tag
uint32_t tag
Definition: movenc.c:1348
av_strndup
char * av_strndup(const char *s, size_t len)
Duplicate a substring of the string s.
Definition: mem.c:279
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:55
read_close
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
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:252
size
ptrdiff_t size
Definition: opengl_enc.c:101
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:442
AV_CODEC_ID_MJPEG
Definition: avcodec.h:114
mpjpeg_read_header
static int mpjpeg_read_header(AVFormatContext *s)
Definition: mpjpegdec.c:134
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
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:262
avio_alloc_context
AVIOContext * avio_alloc_context(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))
Allocate and initialize an AVIOContext for buffered I/O.
Definition: aviobuf.c:116
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
mpjpeg_read_close
static int mpjpeg_read_close(AVFormatContext *s)
Definition: mpjpegdec.c:106
av_default_item_name
av_default_item_name
Definition: libopenh264enc.c:68
AVERROR
#define AVERROR(e)
Definition: error.h:43
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:176
line
Definition: graph2dot.c:48
mpjpeg_demuxer_class
static const AVClass mpjpeg_demuxer_class
Definition: mpjpegdec.c:384
AVStream::codec
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:896
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:463
av_asprintf
char * av_asprintf(const char *fmt,...)
Definition: avstring.c:113
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:462
MPJPEGDemuxContext::searchstr
char * searchstr
Definition: mpjpegdec.c:34
av_strcasecmp
int av_strcasecmp(const char *a, const char *b)
Locale-independent case-insensitive compare.
Definition: avstring.c:213
AV_OPT_SEARCH_CHILDREN
#define AV_OPT_SEARCH_CHILDREN
Search in possible children of the given object first.
Definition: opt.h:556
read_probe
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
value
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:109
ff_mpjpeg_demuxer
AVInputFormat ff_mpjpeg_demuxer
Definition: mpjpegdec.c:391
mpjpeg_read_probe
static int mpjpeg_read_probe(AVProbeData *p)
Definition: mpjpegdec.c:114
AV_OPT_TYPE_BOOL
Definition: opt.h:239
ff_get_line
int ff_get_line(AVIOContext *s, char *buf, int maxlen)
Read a whole line of text from AVIOContext.
Definition: aviobuf.c:706
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:638
AVStream
Stream structure.
Definition: avformat.h:877
parse_multipart_header
static int parse_multipart_header(AVIOContext *pb, int *size, const char *expected_boundary, void *log_ctx)
Definition: mpjpegdec.c:175
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVCodecContext::codec_type
enum AVMediaType codec_type
Definition: avcodec.h:1540
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:1549
av_strdup
char * av_strdup(const char *s)
Duplicate the string s.
Definition: mem.c:267
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1356
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:545
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:67
OFFSET
#define OFFSET(x)
Definition: mpjpegdec.c:375
AVIOContext::error
int error
contains the error code or 0 if no error happened
Definition: avio.h:192
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:460
trim_right
static void trim_right(char *p)
Definition: mpjpegdec.c:40
MPJPEGDemuxContext::strict_mime_boundary
int strict_mime_boundary
Definition: mpjpegdec.c:36
mpjpeg_options
const AVOption mpjpeg_options[]
Definition: mpjpegdec.c:378
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:823
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:472
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
avformat.h
Main libavformat public API header.
av_init_packet
void av_init_packet(AVPacket *pkt)
Initialize optional fields of a packet with default values.
Definition: avpacket.c:33
mpjpeg_read_packet
static int mpjpeg_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mpjpegdec.c:297
av_opt_get
int av_opt_get(void *obj, const char *name, int search_flags, uint8_t **out_val)
Definition: opt.c:678
av_free
#define av_free(p)
Definition: tableprint_vlc.h:34
AVIOContext::eof_reached
int eof_reached
true if eof reached
Definition: avio.h:186
len
int len
Definition: vorbis_enc_data.h:452
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1342
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
start
void INT64 start
Definition: avisynth_c.h:553
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:661
AVMEDIA_TYPE_VIDEO
Definition: avutil.h:193
mpjpeg_get_boundary
static char * mpjpeg_get_boundary(AVIOContext *pb)
Definition: mpjpegdec.c:253
MPJPEGDemuxContext::boundary
char * boundary
Definition: mpjpegdec.c:33
parse_content_length
static int parse_content_length(const char *value)
Definition: mpjpegdec.c:164
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1444
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