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avformat.h
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1 /*
2  * copyright (c) 2001 Fabrice Bellard
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef AVFORMAT_AVFORMAT_H
22 #define AVFORMAT_AVFORMAT_H
23 
24 /**
25  * @file
26  * @ingroup libavf
27  * Main libavformat public API header
28  */
29 
30 /**
31  * @defgroup libavf I/O and Muxing/Demuxing Library
32  * @{
33  *
34  * Libavformat (lavf) is a library for dealing with various media container
35  * formats. Its main two purposes are demuxing - i.e. splitting a media file
36  * into component streams, and the reverse process of muxing - writing supplied
37  * data in a specified container format. It also has an @ref lavf_io
38  * "I/O module" which supports a number of protocols for accessing the data (e.g.
39  * file, tcp, http and others). Before using lavf, you need to call
40  * av_register_all() to register all compiled muxers, demuxers and protocols.
41  * Unless you are absolutely sure you won't use libavformat's network
42  * capabilities, you should also call avformat_network_init().
43  *
44  * A supported input format is described by an AVInputFormat struct, conversely
45  * an output format is described by AVOutputFormat. You can iterate over all
46  * registered input/output formats using the av_iformat_next() /
47  * av_oformat_next() functions. The protocols layer is not part of the public
48  * API, so you can only get the names of supported protocols with the
49  * avio_enum_protocols() function.
50  *
51  * Main lavf structure used for both muxing and demuxing is AVFormatContext,
52  * which exports all information about the file being read or written. As with
53  * most Libavformat structures, its size is not part of public ABI, so it cannot be
54  * allocated on stack or directly with av_malloc(). To create an
55  * AVFormatContext, use avformat_alloc_context() (some functions, like
56  * avformat_open_input() might do that for you).
57  *
58  * Most importantly an AVFormatContext contains:
59  * @li the @ref AVFormatContext.iformat "input" or @ref AVFormatContext.oformat
60  * "output" format. It is either autodetected or set by user for input;
61  * always set by user for output.
62  * @li an @ref AVFormatContext.streams "array" of AVStreams, which describe all
63  * elementary streams stored in the file. AVStreams are typically referred to
64  * using their index in this array.
65  * @li an @ref AVFormatContext.pb "I/O context". It is either opened by lavf or
66  * set by user for input, always set by user for output (unless you are dealing
67  * with an AVFMT_NOFILE format).
68  *
69  * @section lavf_options Passing options to (de)muxers
70  * It is possible to configure lavf muxers and demuxers using the @ref avoptions
71  * mechanism. Generic (format-independent) libavformat options are provided by
72  * AVFormatContext, they can be examined from a user program by calling
73  * av_opt_next() / av_opt_find() on an allocated AVFormatContext (or its AVClass
74  * from avformat_get_class()). Private (format-specific) options are provided by
75  * AVFormatContext.priv_data if and only if AVInputFormat.priv_class /
76  * AVOutputFormat.priv_class of the corresponding format struct is non-NULL.
77  * Further options may be provided by the @ref AVFormatContext.pb "I/O context",
78  * if its AVClass is non-NULL, and the protocols layer. See the discussion on
79  * nesting in @ref avoptions documentation to learn how to access those.
80  *
81  * @section urls
82  * URL strings in libavformat are made of a scheme/protocol, a ':', and a
83  * scheme specific string. URLs without a scheme and ':' used for local files
84  * are supported but deprecated. "file:" should be used for local files.
85  *
86  * It is important that the scheme string is not taken from untrusted
87  * sources without checks.
88  *
89  * Note that some schemes/protocols are quite powerful, allowing access to
90  * both local and remote files, parts of them, concatenations of them, local
91  * audio and video devices and so on.
92  *
93  * @defgroup lavf_decoding Demuxing
94  * @{
95  * Demuxers read a media file and split it into chunks of data (@em packets). A
96  * @ref AVPacket "packet" contains one or more encoded frames which belongs to a
97  * single elementary stream. In the lavf API this process is represented by the
98  * avformat_open_input() function for opening a file, av_read_frame() for
99  * reading a single packet and finally avformat_close_input(), which does the
100  * cleanup.
101  *
102  * @section lavf_decoding_open Opening a media file
103  * The minimum information required to open a file is its URL, which
104  * is passed to avformat_open_input(), as in the following code:
105  * @code
106  * const char *url = "file:in.mp3";
107  * AVFormatContext *s = NULL;
108  * int ret = avformat_open_input(&s, url, NULL, NULL);
109  * if (ret < 0)
110  * abort();
111  * @endcode
112  * The above code attempts to allocate an AVFormatContext, open the
113  * specified file (autodetecting the format) and read the header, exporting the
114  * information stored there into s. Some formats do not have a header or do not
115  * store enough information there, so it is recommended that you call the
116  * avformat_find_stream_info() function which tries to read and decode a few
117  * frames to find missing information.
118  *
119  * In some cases you might want to preallocate an AVFormatContext yourself with
120  * avformat_alloc_context() and do some tweaking on it before passing it to
121  * avformat_open_input(). One such case is when you want to use custom functions
122  * for reading input data instead of lavf internal I/O layer.
123  * To do that, create your own AVIOContext with avio_alloc_context(), passing
124  * your reading callbacks to it. Then set the @em pb field of your
125  * AVFormatContext to newly created AVIOContext.
126  *
127  * Since the format of the opened file is in general not known until after
128  * avformat_open_input() has returned, it is not possible to set demuxer private
129  * options on a preallocated context. Instead, the options should be passed to
130  * avformat_open_input() wrapped in an AVDictionary:
131  * @code
132  * AVDictionary *options = NULL;
133  * av_dict_set(&options, "video_size", "640x480", 0);
134  * av_dict_set(&options, "pixel_format", "rgb24", 0);
135  *
136  * if (avformat_open_input(&s, url, NULL, &options) < 0)
137  * abort();
138  * av_dict_free(&options);
139  * @endcode
140  * This code passes the private options 'video_size' and 'pixel_format' to the
141  * demuxer. They would be necessary for e.g. the rawvideo demuxer, since it
142  * cannot know how to interpret raw video data otherwise. If the format turns
143  * out to be something different than raw video, those options will not be
144  * recognized by the demuxer and therefore will not be applied. Such unrecognized
145  * options are then returned in the options dictionary (recognized options are
146  * consumed). The calling program can handle such unrecognized options as it
147  * wishes, e.g.
148  * @code
149  * AVDictionaryEntry *e;
150  * if (e = av_dict_get(options, "", NULL, AV_DICT_IGNORE_SUFFIX)) {
151  * fprintf(stderr, "Option %s not recognized by the demuxer.\n", e->key);
152  * abort();
153  * }
154  * @endcode
155  *
156  * After you have finished reading the file, you must close it with
157  * avformat_close_input(). It will free everything associated with the file.
158  *
159  * @section lavf_decoding_read Reading from an opened file
160  * Reading data from an opened AVFormatContext is done by repeatedly calling
161  * av_read_frame() on it. Each call, if successful, will return an AVPacket
162  * containing encoded data for one AVStream, identified by
163  * AVPacket.stream_index. This packet may be passed straight into the libavcodec
164  * decoding functions avcodec_send_packet() or avcodec_decode_subtitle2() if the
165  * caller wishes to decode the data.
166  *
167  * AVPacket.pts, AVPacket.dts and AVPacket.duration timing information will be
168  * set if known. They may also be unset (i.e. AV_NOPTS_VALUE for
169  * pts/dts, 0 for duration) if the stream does not provide them. The timing
170  * information will be in AVStream.time_base units, i.e. it has to be
171  * multiplied by the timebase to convert them to seconds.
172  *
173  * If AVPacket.buf is set on the returned packet, then the packet is
174  * allocated dynamically and the user may keep it indefinitely.
175  * Otherwise, if AVPacket.buf is NULL, the packet data is backed by a
176  * static storage somewhere inside the demuxer and the packet is only valid
177  * until the next av_read_frame() call or closing the file. If the caller
178  * requires a longer lifetime, av_dup_packet() will make an av_malloc()ed copy
179  * of it.
180  * In both cases, the packet must be freed with av_packet_unref() when it is no
181  * longer needed.
182  *
183  * @section lavf_decoding_seek Seeking
184  * @}
185  *
186  * @defgroup lavf_encoding Muxing
187  * @{
188  * Muxers take encoded data in the form of @ref AVPacket "AVPackets" and write
189  * it into files or other output bytestreams in the specified container format.
190  *
191  * The main API functions for muxing are avformat_write_header() for writing the
192  * file header, av_write_frame() / av_interleaved_write_frame() for writing the
193  * packets and av_write_trailer() for finalizing the file.
194  *
195  * At the beginning of the muxing process, the caller must first call
196  * avformat_alloc_context() to create a muxing context. The caller then sets up
197  * the muxer by filling the various fields in this context:
198  *
199  * - The @ref AVFormatContext.oformat "oformat" field must be set to select the
200  * muxer that will be used.
201  * - Unless the format is of the AVFMT_NOFILE type, the @ref AVFormatContext.pb
202  * "pb" field must be set to an opened IO context, either returned from
203  * avio_open2() or a custom one.
204  * - Unless the format is of the AVFMT_NOSTREAMS type, at least one stream must
205  * be created with the avformat_new_stream() function. The caller should fill
206  * the @ref AVStream.codecpar "stream codec parameters" information, such as the
207  * codec @ref AVCodecParameters.codec_type "type", @ref AVCodecParameters.codec_id
208  * "id" and other parameters (e.g. width / height, the pixel or sample format,
209  * etc.) as known. The @ref AVStream.time_base "stream timebase" should
210  * be set to the timebase that the caller desires to use for this stream (note
211  * that the timebase actually used by the muxer can be different, as will be
212  * described later).
213  * - It is advised to manually initialize only the relevant fields in
214  * AVCodecParameters, rather than using @ref avcodec_parameters_copy() during
215  * remuxing: there is no guarantee that the codec context values remain valid
216  * for both input and output format contexts.
217  * - The caller may fill in additional information, such as @ref
218  * AVFormatContext.metadata "global" or @ref AVStream.metadata "per-stream"
219  * metadata, @ref AVFormatContext.chapters "chapters", @ref
220  * AVFormatContext.programs "programs", etc. as described in the
221  * AVFormatContext documentation. Whether such information will actually be
222  * stored in the output depends on what the container format and the muxer
223  * support.
224  *
225  * When the muxing context is fully set up, the caller must call
226  * avformat_write_header() to initialize the muxer internals and write the file
227  * header. Whether anything actually is written to the IO context at this step
228  * depends on the muxer, but this function must always be called. Any muxer
229  * private options must be passed in the options parameter to this function.
230  *
231  * The data is then sent to the muxer by repeatedly calling av_write_frame() or
232  * av_interleaved_write_frame() (consult those functions' documentation for
233  * discussion on the difference between them; only one of them may be used with
234  * a single muxing context, they should not be mixed). Do note that the timing
235  * information on the packets sent to the muxer must be in the corresponding
236  * AVStream's timebase. That timebase is set by the muxer (in the
237  * avformat_write_header() step) and may be different from the timebase
238  * requested by the caller.
239  *
240  * Once all the data has been written, the caller must call av_write_trailer()
241  * to flush any buffered packets and finalize the output file, then close the IO
242  * context (if any) and finally free the muxing context with
243  * avformat_free_context().
244  * @}
245  *
246  * @defgroup lavf_io I/O Read/Write
247  * @{
248  * @section lavf_io_dirlist Directory listing
249  * The directory listing API makes it possible to list files on remote servers.
250  *
251  * Some of possible use cases:
252  * - an "open file" dialog to choose files from a remote location,
253  * - a recursive media finder providing a player with an ability to play all
254  * files from a given directory.
255  *
256  * @subsection lavf_io_dirlist_open Opening a directory
257  * At first, a directory needs to be opened by calling avio_open_dir()
258  * supplied with a URL and, optionally, ::AVDictionary containing
259  * protocol-specific parameters. The function returns zero or positive
260  * integer and allocates AVIODirContext on success.
261  *
262  * @code
263  * AVIODirContext *ctx = NULL;
264  * if (avio_open_dir(&ctx, "smb://example.com/some_dir", NULL) < 0) {
265  * fprintf(stderr, "Cannot open directory.\n");
266  * abort();
267  * }
268  * @endcode
269  *
270  * This code tries to open a sample directory using smb protocol without
271  * any additional parameters.
272  *
273  * @subsection lavf_io_dirlist_read Reading entries
274  * Each directory's entry (i.e. file, another directory, anything else
275  * within ::AVIODirEntryType) is represented by AVIODirEntry.
276  * Reading consecutive entries from an opened AVIODirContext is done by
277  * repeatedly calling avio_read_dir() on it. Each call returns zero or
278  * positive integer if successful. Reading can be stopped right after the
279  * NULL entry has been read -- it means there are no entries left to be
280  * read. The following code reads all entries from a directory associated
281  * with ctx and prints their names to standard output.
282  * @code
283  * AVIODirEntry *entry = NULL;
284  * for (;;) {
285  * if (avio_read_dir(ctx, &entry) < 0) {
286  * fprintf(stderr, "Cannot list directory.\n");
287  * abort();
288  * }
289  * if (!entry)
290  * break;
291  * printf("%s\n", entry->name);
292  * avio_free_directory_entry(&entry);
293  * }
294  * @endcode
295  * @}
296  *
297  * @defgroup lavf_codec Demuxers
298  * @{
299  * @defgroup lavf_codec_native Native Demuxers
300  * @{
301  * @}
302  * @defgroup lavf_codec_wrappers External library wrappers
303  * @{
304  * @}
305  * @}
306  * @defgroup lavf_protos I/O Protocols
307  * @{
308  * @}
309  * @defgroup lavf_internal Internal
310  * @{
311  * @}
312  * @}
313  */
314 
315 #include <time.h>
316 #include <stdio.h> /* FILE */
317 #include "libavcodec/avcodec.h"
318 #include "libavutil/dict.h"
319 #include "libavutil/log.h"
320 
321 #include "avio.h"
322 #include "libavformat/version.h"
323 
324 struct AVFormatContext;
325 
326 struct AVDeviceInfoList;
328 
329 /**
330  * @defgroup metadata_api Public Metadata API
331  * @{
332  * @ingroup libavf
333  * The metadata API allows libavformat to export metadata tags to a client
334  * application when demuxing. Conversely it allows a client application to
335  * set metadata when muxing.
336  *
337  * Metadata is exported or set as pairs of key/value strings in the 'metadata'
338  * fields of the AVFormatContext, AVStream, AVChapter and AVProgram structs
339  * using the @ref lavu_dict "AVDictionary" API. Like all strings in FFmpeg,
340  * metadata is assumed to be UTF-8 encoded Unicode. Note that metadata
341  * exported by demuxers isn't checked to be valid UTF-8 in most cases.
342  *
343  * Important concepts to keep in mind:
344  * - Keys are unique; there can never be 2 tags with the same key. This is
345  * also meant semantically, i.e., a demuxer should not knowingly produce
346  * several keys that are literally different but semantically identical.
347  * E.g., key=Author5, key=Author6. In this example, all authors must be
348  * placed in the same tag.
349  * - Metadata is flat, not hierarchical; there are no subtags. If you
350  * want to store, e.g., the email address of the child of producer Alice
351  * and actor Bob, that could have key=alice_and_bobs_childs_email_address.
352  * - Several modifiers can be applied to the tag name. This is done by
353  * appending a dash character ('-') and the modifier name in the order
354  * they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng.
355  * - language -- a tag whose value is localized for a particular language
356  * is appended with the ISO 639-2/B 3-letter language code.
357  * For example: Author-ger=Michael, Author-eng=Mike
358  * The original/default language is in the unqualified "Author" tag.
359  * A demuxer should set a default if it sets any translated tag.
360  * - sorting -- a modified version of a tag that should be used for
361  * sorting will have '-sort' appended. E.g. artist="The Beatles",
362  * artist-sort="Beatles, The".
363  * - Some protocols and demuxers support metadata updates. After a successful
364  * call to av_read_packet(), AVFormatContext.event_flags or AVStream.event_flags
365  * will be updated to indicate if metadata changed. In order to detect metadata
366  * changes on a stream, you need to loop through all streams in the AVFormatContext
367  * and check their individual event_flags.
368  *
369  * - Demuxers attempt to export metadata in a generic format, however tags
370  * with no generic equivalents are left as they are stored in the container.
371  * Follows a list of generic tag names:
372  *
373  @verbatim
374  album -- name of the set this work belongs to
375  album_artist -- main creator of the set/album, if different from artist.
376  e.g. "Various Artists" for compilation albums.
377  artist -- main creator of the work
378  comment -- any additional description of the file.
379  composer -- who composed the work, if different from artist.
380  copyright -- name of copyright holder.
381  creation_time-- date when the file was created, preferably in ISO 8601.
382  date -- date when the work was created, preferably in ISO 8601.
383  disc -- number of a subset, e.g. disc in a multi-disc collection.
384  encoder -- name/settings of the software/hardware that produced the file.
385  encoded_by -- person/group who created the file.
386  filename -- original name of the file.
387  genre -- <self-evident>.
388  language -- main language in which the work is performed, preferably
389  in ISO 639-2 format. Multiple languages can be specified by
390  separating them with commas.
391  performer -- artist who performed the work, if different from artist.
392  E.g for "Also sprach Zarathustra", artist would be "Richard
393  Strauss" and performer "London Philharmonic Orchestra".
394  publisher -- name of the label/publisher.
395  service_name -- name of the service in broadcasting (channel name).
396  service_provider -- name of the service provider in broadcasting.
397  title -- name of the work.
398  track -- number of this work in the set, can be in form current/total.
399  variant_bitrate -- the total bitrate of the bitrate variant that the current stream is part of
400  @endverbatim
401  *
402  * Look in the examples section for an application example how to use the Metadata API.
403  *
404  * @}
405  */
406 
407 /* packet functions */
408 
409 
410 /**
411  * Allocate and read the payload of a packet and initialize its
412  * fields with default values.
413  *
414  * @param s associated IO context
415  * @param pkt packet
416  * @param size desired payload size
417  * @return >0 (read size) if OK, AVERROR_xxx otherwise
418  */
420 
421 
422 /**
423  * Read data and append it to the current content of the AVPacket.
424  * If pkt->size is 0 this is identical to av_get_packet.
425  * Note that this uses av_grow_packet and thus involves a realloc
426  * which is inefficient. Thus this function should only be used
427  * when there is no reasonable way to know (an upper bound of)
428  * the final size.
429  *
430  * @param s associated IO context
431  * @param pkt packet
432  * @param size amount of data to read
433  * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data
434  * will not be lost even if an error occurs.
435  */
437 
438 #if FF_API_LAVF_FRAC
439 /*************************************************/
440 /* fractional numbers for exact pts handling */
441 
442 /**
443  * The exact value of the fractional number is: 'val + num / den'.
444  * num is assumed to be 0 <= num < den.
445  */
446 typedef struct AVFrac {
447  int64_t val, num, den;
448 } AVFrac;
449 #endif
450 
451 /*************************************************/
452 /* input/output formats */
453 
454 struct AVCodecTag;
455 
456 /**
457  * This structure contains the data a format has to probe a file.
458  */
459 typedef struct AVProbeData {
460  const char *filename;
461  unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
462  int buf_size; /**< Size of buf except extra allocated bytes */
463  const char *mime_type; /**< mime_type, when known. */
464 } AVProbeData;
465 
466 #define AVPROBE_SCORE_RETRY (AVPROBE_SCORE_MAX/4)
467 #define AVPROBE_SCORE_STREAM_RETRY (AVPROBE_SCORE_MAX/4-1)
468 
469 #define AVPROBE_SCORE_EXTENSION 50 ///< score for file extension
470 #define AVPROBE_SCORE_MIME 75 ///< score for file mime type
471 #define AVPROBE_SCORE_MAX 100 ///< maximum score
472 
473 #define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
474 
475 /// Demuxer will use avio_open, no opened file should be provided by the caller.
476 #define AVFMT_NOFILE 0x0001
477 #define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
478 #define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
479 #if FF_API_LAVF_FMT_RAWPICTURE
480 #define AVFMT_RAWPICTURE 0x0020 /**< Format wants AVPicture structure for
481  raw picture data. @deprecated Not used anymore */
482 #endif
483 #define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
484 #define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
485 #define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
486 #define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */
487 #define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */
488 #define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */
489 #define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */
490 #define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fall back on binary search via read_timestamp */
491 #define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fall back on generic search */
492 #define AVFMT_NO_BYTE_SEEK 0x8000 /**< Format does not allow seeking by bytes */
493 #define AVFMT_ALLOW_FLUSH 0x10000 /**< Format allows flushing. If not set, the muxer will not receive a NULL packet in the write_packet function. */
494 #define AVFMT_TS_NONSTRICT 0x20000 /**< Format does not require strictly
495  increasing timestamps, but they must
496  still be monotonic */
497 #define AVFMT_TS_NEGATIVE 0x40000 /**< Format allows muxing negative
498  timestamps. If not set the timestamp
499  will be shifted in av_write_frame and
500  av_interleaved_write_frame so they
501  start from 0.
502  The user or muxer can override this through
503  AVFormatContext.avoid_negative_ts
504  */
505 
506 #define AVFMT_SEEK_TO_PTS 0x4000000 /**< Seeking is based on PTS */
507 
508 /**
509  * @addtogroup lavf_encoding
510  * @{
511  */
512 typedef struct AVOutputFormat {
513  const char *name;
514  /**
515  * Descriptive name for the format, meant to be more human-readable
516  * than name. You should use the NULL_IF_CONFIG_SMALL() macro
517  * to define it.
518  */
519  const char *long_name;
520  const char *mime_type;
521  const char *extensions; /**< comma-separated filename extensions */
522  /* output support */
523  enum AVCodecID audio_codec; /**< default audio codec */
524  enum AVCodecID video_codec; /**< default video codec */
525  enum AVCodecID subtitle_codec; /**< default subtitle codec */
526  /**
527  * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER,
528  * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
529  * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH,
530  * AVFMT_TS_NONSTRICT, AVFMT_TS_NEGATIVE
531  */
532  int flags;
534  /**
535  * List of supported codec_id-codec_tag pairs, ordered by "better
536  * choice first". The arrays are all terminated by AV_CODEC_ID_NONE.
537  */
538  const struct AVCodecTag * const *codec_tag;
539 
540 
541  const AVClass *priv_class; ///< AVClass for the private context
542 
543  /*****************************************************************
544  * No fields below this line are part of the public API. They
545  * may not be used outside of libavformat and can be changed and
546  * removed at will.
547  * New public fields should be added right above.
548  *****************************************************************
549  */
551  /**
552  * size of private data so that it can be allocated in the wrapper
553  */
554  int priv_data_size;
555 
556  int (*write_header)(struct AVFormatContext *);
557  /**
558  * Write a packet. If AVFMT_ALLOW_FLUSH is set in flags,
559  * pkt can be NULL in order to flush data buffered in the muxer.
560  * When flushing, return 0 if there still is more data to flush,
561  * or 1 if everything was flushed and there is no more buffered
562  * data.
563  */
564  int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
565  int (*write_trailer)(struct AVFormatContext *);
566  /**
567  * Currently only used to set pixel format if not YUV420P.
568  */
569  int (*interleave_packet)(struct AVFormatContext *, AVPacket *out,
570  AVPacket *in, int flush);
571  /**
572  * Test if the given codec can be stored in this container.
573  *
574  * @return 1 if the codec is supported, 0 if it is not.
575  * A negative number if unknown.
576  * MKTAG('A', 'P', 'I', 'C') if the codec is only supported as AV_DISPOSITION_ATTACHED_PIC
577  */
578  int (*query_codec)(enum AVCodecID id, int std_compliance);
579 
580  void (*get_output_timestamp)(struct AVFormatContext *s, int stream,
581  int64_t *dts, int64_t *wall);
582  /**
583  * Allows sending messages from application to device.
584  */
585  int (*control_message)(struct AVFormatContext *s, int type,
586  void *data, size_t data_size);
588  /**
589  * Write an uncoded AVFrame.
590  *
591  * See av_write_uncoded_frame() for details.
592  *
593  * The library will free *frame afterwards, but the muxer can prevent it
594  * by setting the pointer to NULL.
595  */
596  int (*write_uncoded_frame)(struct AVFormatContext *, int stream_index,
597  AVFrame **frame, unsigned flags);
598  /**
599  * Returns device list with it properties.
600  * @see avdevice_list_devices() for more details.
601  */
602  int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
603  /**
604  * Initialize device capabilities submodule.
605  * @see avdevice_capabilities_create() for more details.
606  */
608  /**
609  * Free device capabilities submodule.
610  * @see avdevice_capabilities_free() for more details.
611  */
613  enum AVCodecID data_codec; /**< default data codec */
614  /**
615  * Initialize format. May allocate data here, and set any AVFormatContext or
616  * AVStream parameters that need to be set before packets are sent.
617  * This method must not write output.
618  *
619  * Any allocations made here must be freed in deinit().
620  */
621  int (*init)(struct AVFormatContext *);
622  /**
623  * Deinitialize format. If present, this is called whenever the muxer is being
624  * destroyed, regardless of whether or not the header has been written.
625  *
626  * If a trailer is being written, this is called after write_trailer().
627  *
628  * This is called if init() fails as well.
629  */
631  /**
632  * Set up any necessary bitstream filtering and extract any extra data needed
633  * for the global header.
634  * Return 0 if more packets from this stream must be checked; 1 if not.
635  */
636  int (*check_bitstream)(struct AVFormatContext *, const AVPacket *pkt);
638 /**
639  * @}
640  */
641 
642 /**
643  * @addtogroup lavf_decoding
644  * @{
645  */
646 typedef struct AVInputFormat {
647  /**
648  * A comma separated list of short names for the format. New names
649  * may be appended with a minor bump.
650  */
651  const char *name;
652 
653  /**
654  * Descriptive name for the format, meant to be more human-readable
655  * than name. You should use the NULL_IF_CONFIG_SMALL() macro
656  * to define it.
657  */
658  const char *long_name;
659 
660  /**
661  * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
662  * AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
663  * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK, AVFMT_SEEK_TO_PTS.
664  */
665  int flags;
666 
667  /**
668  * If extensions are defined, then no probe is done. You should
669  * usually not use extension format guessing because it is not
670  * reliable enough
671  */
672  const char *extensions;
673 
674  const struct AVCodecTag * const *codec_tag;
675 
676  const AVClass *priv_class; ///< AVClass for the private context
677 
678  /**
679  * Comma-separated list of mime types.
680  * It is used check for matching mime types while probing.
681  * @see av_probe_input_format2
682  */
683  const char *mime_type;
684 
685  /*****************************************************************
686  * No fields below this line are part of the public API. They
687  * may not be used outside of libavformat and can be changed and
688  * removed at will.
689  * New public fields should be added right above.
690  *****************************************************************
691  */
693 
694  /**
695  * Raw demuxers store their codec ID here.
696  */
697  int raw_codec_id;
698 
699  /**
700  * Size of private data so that it can be allocated in the wrapper.
701  */
702  int priv_data_size;
703 
704  /**
705  * Tell if a given file has a chance of being parsed as this format.
706  * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
707  * big so you do not have to check for that unless you need more.
708  */
709  int (*read_probe)(AVProbeData *);
710 
711  /**
712  * Read the format header and initialize the AVFormatContext
713  * structure. Return 0 if OK. 'avformat_new_stream' should be
714  * called to create new streams.
715  */
716  int (*read_header)(struct AVFormatContext *);
717 
718  /**
719  * Read one packet and put it in 'pkt'. pts and flags are also
720  * set. 'avformat_new_stream' can be called only if the flag
721  * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
722  * background thread).
723  * @return 0 on success, < 0 on error.
724  * When returning an error, pkt must not have been allocated
725  * or must be freed before returning
726  */
727  int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
728 
729  /**
730  * Close the stream. The AVFormatContext and AVStreams are not
731  * freed by this function
732  */
733  int (*read_close)(struct AVFormatContext *);
734 
735  /**
736  * Seek to a given timestamp relative to the frames in
737  * stream component stream_index.
738  * @param stream_index Must not be -1.
739  * @param flags Selects which direction should be preferred if no exact
740  * match is available.
741  * @return >= 0 on success (but not necessarily the new offset)
742  */
743  int (*read_seek)(struct AVFormatContext *,
744  int stream_index, int64_t timestamp, int flags);
745 
746  /**
747  * Get the next timestamp in stream[stream_index].time_base units.
748  * @return the timestamp or AV_NOPTS_VALUE if an error occurred
749  */
750  int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
751  int64_t *pos, int64_t pos_limit);
753  /**
754  * Start/resume playing - only meaningful if using a network-based format
755  * (RTSP).
756  */
757  int (*read_play)(struct AVFormatContext *);
758 
759  /**
760  * Pause playing - only meaningful if using a network-based format
761  * (RTSP).
762  */
763  int (*read_pause)(struct AVFormatContext *);
764 
765  /**
766  * Seek to timestamp ts.
767  * Seeking will be done so that the point from which all active streams
768  * can be presented successfully will be closest to ts and within min/max_ts.
769  * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
770  */
771  int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
773  /**
774  * Returns device list with it properties.
775  * @see avdevice_list_devices() for more details.
776  */
777  int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
778 
779  /**
780  * Initialize device capabilities submodule.
781  * @see avdevice_capabilities_create() for more details.
782  */
784 
785  /**
786  * Free device capabilities submodule.
787  * @see avdevice_capabilities_free() for more details.
788  */
790 } AVInputFormat;
791 /**
792  * @}
793  */
794 
795 enum AVStreamParseType {
797  AVSTREAM_PARSE_FULL, /**< full parsing and repack */
798  AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
799  AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
800  AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
801  AVSTREAM_PARSE_FULL_RAW=MKTAG(0,'R','A','W'), /**< full parsing and repack with timestamp and position generation by parser for raw
802  this assumes that each packet in the file contains no demuxer level headers and
803  just codec level data, otherwise position generation would fail */
804 };
806 typedef struct AVIndexEntry {
807  int64_t pos;
808  int64_t timestamp; /**<
809  * Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are available
810  * when seeking to this entry. That means preferable PTS on keyframe based formats.
811  * But demuxers can choose to store a different timestamp, if it is more convenient for the implementation or nothing better
812  * is known
813  */
814 #define AVINDEX_KEYFRAME 0x0001
815  int flags:2;
816  int size:30; //Yeah, trying to keep the size of this small to reduce memory requirements (it is 24 vs. 32 bytes due to possible 8-byte alignment).
817  int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
818 } AVIndexEntry;
819 
820 #define AV_DISPOSITION_DEFAULT 0x0001
821 #define AV_DISPOSITION_DUB 0x0002
822 #define AV_DISPOSITION_ORIGINAL 0x0004
823 #define AV_DISPOSITION_COMMENT 0x0008
824 #define AV_DISPOSITION_LYRICS 0x0010
825 #define AV_DISPOSITION_KARAOKE 0x0020
827 /**
828  * Track should be used during playback by default.
829  * Useful for subtitle track that should be displayed
830  * even when user did not explicitly ask for subtitles.
831  */
832 #define AV_DISPOSITION_FORCED 0x0040
833 #define AV_DISPOSITION_HEARING_IMPAIRED 0x0080 /**< stream for hearing impaired audiences */
834 #define AV_DISPOSITION_VISUAL_IMPAIRED 0x0100 /**< stream for visual impaired audiences */
835 #define AV_DISPOSITION_CLEAN_EFFECTS 0x0200 /**< stream without voice */
836 /**
837  * The stream is stored in the file as an attached picture/"cover art" (e.g.
838  * APIC frame in ID3v2). The single packet associated with it will be returned
839  * among the first few packets read from the file unless seeking takes place.
840  * It can also be accessed at any time in AVStream.attached_pic.
841  */
842 #define AV_DISPOSITION_ATTACHED_PIC 0x0400
845 
846 /**
847  * To specify text track kind (different from subtitles default).
848  */
849 #define AV_DISPOSITION_CAPTIONS 0x10000
850 #define AV_DISPOSITION_DESCRIPTIONS 0x20000
851 #define AV_DISPOSITION_METADATA 0x40000
852 
853 /**
854  * Options for behavior on timestamp wrap detection.
855  */
856 #define AV_PTS_WRAP_IGNORE 0 ///< ignore the wrap
857 #define AV_PTS_WRAP_ADD_OFFSET 1 ///< add the format specific offset on wrap detection
858 #define AV_PTS_WRAP_SUB_OFFSET -1 ///< subtract the format specific offset on wrap detection
860 /**
861  * Stream structure.
862  * New fields can be added to the end with minor version bumps.
863  * Removal, reordering and changes to existing fields require a major
864  * version bump.
865  * sizeof(AVStream) must not be used outside libav*.
866  */
867 typedef struct AVStream {
868  int index; /**< stream index in AVFormatContext */
869  /**
870  * Format-specific stream ID.
871  * decoding: set by libavformat
872  * encoding: set by the user, replaced by libavformat if left unset
873  */
874  int id;
875 #if FF_API_LAVF_AVCTX
876  /**
877  * @deprecated use the codecpar struct instead
878  */
880  AVCodecContext *codec;
881 #endif
882  void *priv_data;
884 #if FF_API_LAVF_FRAC
885  /**
886  * @deprecated this field is unused
887  */
889  struct AVFrac pts;
890 #endif
892  /**
893  * This is the fundamental unit of time (in seconds) in terms
894  * of which frame timestamps are represented.
895  *
896  * decoding: set by libavformat
897  * encoding: May be set by the caller before avformat_write_header() to
898  * provide a hint to the muxer about the desired timebase. In
899  * avformat_write_header(), the muxer will overwrite this field
900  * with the timebase that will actually be used for the timestamps
901  * written into the file (which may or may not be related to the
902  * user-provided one, depending on the format).
903  */
905 
906  /**
907  * Decoding: pts of the first frame of the stream in presentation order, in stream time base.
908  * Only set this if you are absolutely 100% sure that the value you set
909  * it to really is the pts of the first frame.
910  * This may be undefined (AV_NOPTS_VALUE).
911  * @note The ASF header does NOT contain a correct start_time the ASF
912  * demuxer must NOT set this.
913  */
914  int64_t start_time;
915 
916  /**
917  * Decoding: duration of the stream, in stream time base.
918  * If a source file does not specify a duration, but does specify
919  * a bitrate, this value will be estimated from bitrate and file size.
920  */
921  int64_t duration;
922 
923  int64_t nb_frames; ///< number of frames in this stream if known or 0
924 
925  int disposition; /**< AV_DISPOSITION_* bit field */
926 
927  enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
928 
929  /**
930  * sample aspect ratio (0 if unknown)
931  * - encoding: Set by user.
932  * - decoding: Set by libavformat.
933  */
935 
937 
938  /**
939  * Average framerate
940  *
941  * - demuxing: May be set by libavformat when creating the stream or in
942  * avformat_find_stream_info().
943  * - muxing: May be set by the caller before avformat_write_header().
944  */
946 
947  /**
948  * For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet
949  * will contain the attached picture.
950  *
951  * decoding: set by libavformat, must not be modified by the caller.
952  * encoding: unused
953  */
955 
956  /**
957  * An array of side data that applies to the whole stream (i.e. the
958  * container does not allow it to change between packets).
959  *
960  * There may be no overlap between the side data in this array and side data
961  * in the packets. I.e. a given side data is either exported by the muxer
962  * (demuxing) / set by the caller (muxing) in this array, then it never
963  * appears in the packets, or the side data is exported / sent through
964  * the packets (always in the first packet where the value becomes known or
965  * changes), then it does not appear in this array.
966  *
967  * - demuxing: Set by libavformat when the stream is created.
968  * - muxing: May be set by the caller before avformat_write_header().
969  *
970  * Freed by libavformat in avformat_free_context().
971  *
972  * @see av_format_inject_global_side_data()
973  */
975  /**
976  * The number of elements in the AVStream.side_data array.
977  */
978  int nb_side_data;
979 
980  /**
981  * Flags for the user to detect events happening on the stream. Flags must
982  * be cleared by the user once the event has been handled.
983  * A combination of AVSTREAM_EVENT_FLAG_*.
984  */
985  int event_flags;
986 #define AVSTREAM_EVENT_FLAG_METADATA_UPDATED 0x0001 ///< The call resulted in updated metadata.
988  /*****************************************************************
989  * All fields below this line are not part of the public API. They
990  * may not be used outside of libavformat and can be changed and
991  * removed at will.
992  * New public fields should be added right above.
993  *****************************************************************
994  */
996  /**
997  * Stream information used internally by av_find_stream_info()
998  */
999 #define MAX_STD_TIMEBASES (30*12+30+3+6)
1000  struct {
1001  int64_t last_dts;
1002  int64_t duration_gcd;
1003  int duration_count;
1004  int64_t rfps_duration_sum;
1005  double (*duration_error)[2][MAX_STD_TIMEBASES];
1006  int64_t codec_info_duration;
1009  /**
1010  * 0 -> decoder has not been searched for yet.
1011  * >0 -> decoder found
1012  * <0 -> decoder with codec_id == -found_decoder has not been found
1013  */
1016  int64_t last_duration;
1017 
1018  /**
1019  * Those are used for average framerate estimation.
1020  */
1021  int64_t fps_first_dts;
1022  int fps_first_dts_idx;
1023  int64_t fps_last_dts;
1024  int fps_last_dts_idx;
1026  } *info;
1027 
1028  int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
1029 
1030  // Timestamp generation support:
1031  /**
1032  * Timestamp corresponding to the last dts sync point.
1033  *
1034  * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
1035  * a DTS is received from the underlying container. Otherwise set to
1036  * AV_NOPTS_VALUE by default.
1037  */
1038  int64_t first_dts;
1039  int64_t cur_dts;
1040  int64_t last_IP_pts;
1041  int last_IP_duration;
1042 
1043  /**
1044  * Number of packets to buffer for codec probing
1045  */
1046  int probe_packets;
1048  /**
1049  * Number of frames that have been demuxed during av_find_stream_info()
1050  */
1052 
1053  /* av_read_frame() support */
1056 
1057  /**
1058  * last packet in packet_buffer for this stream when muxing.
1059  */
1062 #define MAX_REORDER_DELAY 16
1065  AVIndexEntry *index_entries; /**< Only used if the format does not
1066  support seeking natively. */
1067  int nb_index_entries;
1068  unsigned int index_entries_allocated_size;
1070  /**
1071  * Real base framerate of the stream.
1072  * This is the lowest framerate with which all timestamps can be
1073  * represented accurately (it is the least common multiple of all
1074  * framerates in the stream). Note, this value is just a guess!
1075  * For example, if the time base is 1/90000 and all frames have either
1076  * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
1077  *
1078  * Code outside avformat should access this field using:
1079  * av_stream_get/set_r_frame_rate(stream)
1080  */
1082 
1083  /**
1084  * Stream Identifier
1085  * This is the MPEG-TS stream identifier +1
1086  * 0 means unknown
1087  */
1088  int stream_identifier;
1089 
1092 
1093  /**
1094  * stream probing state
1095  * -1 -> probing finished
1096  * 0 -> no probing requested
1097  * rest -> perform probing with request_probe being the minimum score to accept.
1098  * NOT PART OF PUBLIC API
1099  */
1101  /**
1102  * Indicates that everything up to the next keyframe
1103  * should be discarded.
1104  */
1105  int skip_to_keyframe;
1106 
1107  /**
1108  * Number of samples to skip at the start of the frame decoded from the next packet.
1109  */
1110  int skip_samples;
1111 
1112  /**
1113  * If not 0, the number of samples that should be skipped from the start of
1114  * the stream (the samples are removed from packets with pts==0, which also
1115  * assumes negative timestamps do not happen).
1116  * Intended for use with formats such as mp3 with ad-hoc gapless audio
1117  * support.
1118  */
1120 
1121  /**
1122  * If not 0, the first audio sample that should be discarded from the stream.
1123  * This is broken by design (needs global sample count), but can't be
1124  * avoided for broken by design formats such as mp3 with ad-hoc gapless
1125  * audio support.
1126  */
1127  int64_t first_discard_sample;
1129  /**
1130  * The sample after last sample that is intended to be discarded after
1131  * first_discard_sample. Works on frame boundaries only. Used to prevent
1132  * early EOF if the gapless info is broken (considered concatenated mp3s).
1133  */
1134  int64_t last_discard_sample;
1135 
1136  /**
1137  * Number of internally decoded frames, used internally in libavformat, do not access
1138  * its lifetime differs from info which is why it is not in that structure.
1139  */
1140  int nb_decoded_frames;
1141 
1142  /**
1143  * Timestamp offset added to timestamps before muxing
1144  * NOT PART OF PUBLIC API
1145  */
1146  int64_t mux_ts_offset;
1147 
1148  /**
1149  * Internal data to check for wrapping of the time stamp
1150  */
1151  int64_t pts_wrap_reference;
1152 
1153  /**
1154  * Options for behavior, when a wrap is detected.
1155  *
1156  * Defined by AV_PTS_WRAP_ values.
1157  *
1158  * If correction is enabled, there are two possibilities:
1159  * If the first time stamp is near the wrap point, the wrap offset
1160  * will be subtracted, which will create negative time stamps.
1161  * Otherwise the offset will be added.
1162  */
1163  int pts_wrap_behavior;
1164 
1165  /**
1166  * Internal data to prevent doing update_initial_durations() twice
1167  */
1169 
1170  /**
1171  * Internal data to generate dts from pts
1172  */
1175 
1176  /**
1177  * Internal data to analyze DTS and detect faulty mpeg streams
1178  */
1179  int64_t last_dts_for_order_check;
1183  /**
1184  * Internal data to inject global side data
1185  */
1187 
1188  /**
1189  * String containing paris of key and values describing recommended encoder configuration.
1190  * Paris are separated by ','.
1191  * Keys are separated from values by '='.
1192  */
1194 
1195  /**
1196  * display aspect ratio (0 if unknown)
1197  * - encoding: unused
1198  * - decoding: Set by libavformat to calculate sample_aspect_ratio internally
1199  */
1201 
1202  struct FFFrac *priv_pts;
1203 
1204  /**
1205  * An opaque field for libavformat internal usage.
1206  * Must not be accessed in any way by callers.
1207  */
1208  AVStreamInternal *internal;
1210  /*
1211  * Codec parameters associated with this stream. Allocated and freed by
1212  * libavformat in avformat_new_stream() and avformat_free_context()
1213  * respectively.
1214  *
1215  * - demuxing: filled by libavformat on stream creation or in
1216  * avformat_find_stream_info()
1217  * - muxing: filled by the caller before avformat_write_header()
1218  */
1220 } AVStream;
1221 
1226 void av_stream_set_recommended_encoder_configuration(AVStream *s, char *configuration);
1227 
1228 /**
1229  * Returns the pts of the last muxed packet + its duration
1230  *
1231  * the retuned value is undefined when used with a demuxer.
1232  */
1233 int64_t av_stream_get_end_pts(const AVStream *st);
1234 
1235 #define AV_PROGRAM_RUNNING 1
1236 
1237 /**
1238  * New fields can be added to the end with minor version bumps.
1239  * Removal, reordering and changes to existing fields require a major
1240  * version bump.
1241  * sizeof(AVProgram) must not be used outside libav*.
1242  */
1243 typedef struct AVProgram {
1244  int id;
1245  int flags;
1246  enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
1247  unsigned int *stream_index;
1248  unsigned int nb_stream_indexes;
1250 
1251  int program_num;
1252  int pmt_pid;
1253  int pcr_pid;
1255  /*****************************************************************
1256  * All fields below this line are not part of the public API. They
1257  * may not be used outside of libavformat and can be changed and
1258  * removed at will.
1259  * New public fields should be added right above.
1260  *****************************************************************
1261  */
1262  int64_t start_time;
1263  int64_t end_time;
1264 
1265  int64_t pts_wrap_reference; ///< reference dts for wrap detection
1266  int pts_wrap_behavior; ///< behavior on wrap detection
1267 } AVProgram;
1268 
1269 #define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
1270  (streams are added dynamically) */
1272 typedef struct AVChapter {
1273  int id; ///< unique ID to identify the chapter
1274  AVRational time_base; ///< time base in which the start/end timestamps are specified
1275  int64_t start, end; ///< chapter start/end time in time_base units
1277 } AVChapter;
1279 
1280 /**
1281  * Callback used by devices to communicate with application.
1282  */
1283 typedef int (*av_format_control_message)(struct AVFormatContext *s, int type,
1284  void *data, size_t data_size);
1286 typedef int (*AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags,
1288 
1289 /**
1290  * The duration of a video can be estimated through various ways, and this enum can be used
1291  * to know how the duration was estimated.
1292  */
1294  AVFMT_DURATION_FROM_PTS, ///< Duration accurately estimated from PTSes
1295  AVFMT_DURATION_FROM_STREAM, ///< Duration estimated from a stream with a known duration
1296  AVFMT_DURATION_FROM_BITRATE ///< Duration estimated from bitrate (less accurate)
1297 };
1298 
1299 typedef struct AVFormatInternal AVFormatInternal;
1300 
1301 /**
1302  * Format I/O context.
1303  * New fields can be added to the end with minor version bumps.
1304  * Removal, reordering and changes to existing fields require a major
1305  * version bump.
1306  * sizeof(AVFormatContext) must not be used outside libav*, use
1307  * avformat_alloc_context() to create an AVFormatContext.
1308  *
1309  * Fields can be accessed through AVOptions (av_opt*),
1310  * the name string used matches the associated command line parameter name and
1311  * can be found in libavformat/options_table.h.
1312  * The AVOption/command line parameter names differ in some cases from the C
1313  * structure field names for historic reasons or brevity.
1314  */
1315 typedef struct AVFormatContext {
1316  /**
1317  * A class for logging and @ref avoptions. Set by avformat_alloc_context().
1318  * Exports (de)muxer private options if they exist.
1319  */
1320  const AVClass *av_class;
1321 
1322  /**
1323  * The input container format.
1324  *
1325  * Demuxing only, set by avformat_open_input().
1326  */
1327  struct AVInputFormat *iformat;
1328 
1329  /**
1330  * The output container format.
1331  *
1332  * Muxing only, must be set by the caller before avformat_write_header().
1333  */
1334  struct AVOutputFormat *oformat;
1335 
1336  /**
1337  * Format private data. This is an AVOptions-enabled struct
1338  * if and only if iformat/oformat.priv_class is not NULL.
1339  *
1340  * - muxing: set by avformat_write_header()
1341  * - demuxing: set by avformat_open_input()
1342  */
1343  void *priv_data;
1345  /**
1346  * I/O context.
1347  *
1348  * - demuxing: either set by the user before avformat_open_input() (then
1349  * the user must close it manually) or set by avformat_open_input().
1350  * - muxing: set by the user before avformat_write_header(). The caller must
1351  * take care of closing / freeing the IO context.
1352  *
1353  * Do NOT set this field if AVFMT_NOFILE flag is set in
1354  * iformat/oformat.flags. In such a case, the (de)muxer will handle
1355  * I/O in some other way and this field will be NULL.
1356  */
1357  AVIOContext *pb;
1358 
1359  /* stream info */
1360  /**
1361  * Flags signalling stream properties. A combination of AVFMTCTX_*.
1362  * Set by libavformat.
1363  */
1364  int ctx_flags;
1365 
1366  /**
1367  * Number of elements in AVFormatContext.streams.
1368  *
1369  * Set by avformat_new_stream(), must not be modified by any other code.
1370  */
1371  unsigned int nb_streams;
1372  /**
1373  * A list of all streams in the file. New streams are created with
1374  * avformat_new_stream().
1375  *
1376  * - demuxing: streams are created by libavformat in avformat_open_input().
1377  * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
1378  * appear in av_read_frame().
1379  * - muxing: streams are created by the user before avformat_write_header().
1380  *
1381  * Freed by libavformat in avformat_free_context().
1382  */
1383  AVStream **streams;
1384 
1385  /**
1386  * input or output filename
1387  *
1388  * - demuxing: set by avformat_open_input()
1389  * - muxing: may be set by the caller before avformat_write_header()
1390  */
1391  char filename[1024];
1392 
1393  /**
1394  * Position of the first frame of the component, in
1395  * AV_TIME_BASE fractional seconds. NEVER set this value directly:
1396  * It is deduced from the AVStream values.
1397  *
1398  * Demuxing only, set by libavformat.
1399  */
1400  int64_t start_time;
1402  /**
1403  * Duration of the stream, in AV_TIME_BASE fractional
1404  * seconds. Only set this value if you know none of the individual stream
1405  * durations and also do not set any of them. This is deduced from the
1406  * AVStream values if not set.
1407  *
1408  * Demuxing only, set by libavformat.
1409  */
1410  int64_t duration;
1411 
1412  /**
1413  * Total stream bitrate in bit/s, 0 if not
1414  * available. Never set it directly if the file_size and the
1415  * duration are known as FFmpeg can compute it automatically.
1416  */
1417  int64_t bit_rate;
1418 
1419  unsigned int packet_size;
1421 
1422  /**
1423  * Flags modifying the (de)muxer behaviour. A combination of AVFMT_FLAG_*.
1424  * Set by the user before avformat_open_input() / avformat_write_header().
1425  */
1426  int flags;
1427 #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
1428 #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
1429 #define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
1430 #define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
1431 #define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
1432 #define AVFMT_FLAG_NOPARSE 0x0020 ///< Do not use AVParsers, you also must set AVFMT_FLAG_NOFILLIN as the fillin code works on frames and no parsing -> no frames. Also seeking to frames can not work if parsing to find frame boundaries has been disabled
1433 #define AVFMT_FLAG_NOBUFFER 0x0040 ///< Do not buffer frames when possible
1434 #define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
1435 #define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted
1436 #define AVFMT_FLAG_FLUSH_PACKETS 0x0200 ///< Flush the AVIOContext every packet.
1437 /**
1438  * When muxing, try to avoid writing any random/volatile data to the output.
1439  * This includes any random IDs, real-time timestamps/dates, muxer version, etc.
1440  *
1441  * This flag is mainly intended for testing.
1442  */
1443 #define AVFMT_FLAG_BITEXACT 0x0400
1444 #define AVFMT_FLAG_MP4A_LATM 0x8000 ///< Enable RTP MP4A-LATM payload
1445 #define AVFMT_FLAG_SORT_DTS 0x10000 ///< try to interleave outputted packets by dts (using this flag can slow demuxing down)
1446 #define AVFMT_FLAG_PRIV_OPT 0x20000 ///< Enable use of private options by delaying codec open (this could be made default once all code is converted)
1447 #define AVFMT_FLAG_KEEP_SIDE_DATA 0x40000 ///< Don't merge side data but keep it separate.
1448 #define AVFMT_FLAG_FAST_SEEK 0x80000 ///< Enable fast, but inaccurate seeks for some formats
1449 
1450  /**
1451  * Maximum size of the data read from input for determining
1452  * the input container format.
1453  * Demuxing only, set by the caller before avformat_open_input().
1454  */
1455  int64_t probesize;
1457  /**
1458  * Maximum duration (in AV_TIME_BASE units) of the data read
1459  * from input in avformat_find_stream_info().
1460  * Demuxing only, set by the caller before avformat_find_stream_info().
1461  * Can be set to 0 to let avformat choose using a heuristic.
1462  */
1463  int64_t max_analyze_duration;
1464 
1465  const uint8_t *key;
1466  int keylen;
1467 
1468  unsigned int nb_programs;
1469  AVProgram **programs;
1470 
1471  /**
1472  * Forced video codec_id.
1473  * Demuxing: Set by user.
1474  */
1477  /**
1478  * Forced audio codec_id.
1479  * Demuxing: Set by user.
1480  */
1482 
1483  /**
1484  * Forced subtitle codec_id.
1485  * Demuxing: Set by user.
1486  */
1488 
1489  /**
1490  * Maximum amount of memory in bytes to use for the index of each stream.
1491  * If the index exceeds this size, entries will be discarded as
1492  * needed to maintain a smaller size. This can lead to slower or less
1493  * accurate seeking (depends on demuxer).
1494  * Demuxers for which a full in-memory index is mandatory will ignore
1495  * this.
1496  * - muxing: unused
1497  * - demuxing: set by user
1498  */
1499  unsigned int max_index_size;
1500 
1501  /**
1502  * Maximum amount of memory in bytes to use for buffering frames
1503  * obtained from realtime capture devices.
1504  */
1505  unsigned int max_picture_buffer;
1506 
1507  /**
1508  * Number of chapters in AVChapter array.
1509  * When muxing, chapters are normally written in the file header,
1510  * so nb_chapters should normally be initialized before write_header
1511  * is called. Some muxers (e.g. mov and mkv) can also write chapters
1512  * in the trailer. To write chapters in the trailer, nb_chapters
1513  * must be zero when write_header is called and non-zero when
1514  * write_trailer is called.
1515  * - muxing: set by user
1516  * - demuxing: set by libavformat
1517  */
1518  unsigned int nb_chapters;
1519  AVChapter **chapters;
1520 
1521  /**
1522  * Metadata that applies to the whole file.
1523  *
1524  * - demuxing: set by libavformat in avformat_open_input()
1525  * - muxing: may be set by the caller before avformat_write_header()
1526  *
1527  * Freed by libavformat in avformat_free_context().
1528  */
1530 
1531  /**
1532  * Start time of the stream in real world time, in microseconds
1533  * since the Unix epoch (00:00 1st January 1970). That is, pts=0 in the
1534  * stream was captured at this real world time.
1535  * - muxing: Set by the caller before avformat_write_header(). If set to
1536  * either 0 or AV_NOPTS_VALUE, then the current wall-time will
1537  * be used.
1538  * - demuxing: Set by libavformat. AV_NOPTS_VALUE if unknown. Note that
1539  * the value may become known after some number of frames
1540  * have been received.
1541  */
1542  int64_t start_time_realtime;
1543 
1544  /**
1545  * The number of frames used for determining the framerate in
1546  * avformat_find_stream_info().
1547  * Demuxing only, set by the caller before avformat_find_stream_info().
1548  */
1549  int fps_probe_size;
1550 
1551  /**
1552  * Error recognition; higher values will detect more errors but may
1553  * misdetect some more or less valid parts as errors.
1554  * Demuxing only, set by the caller before avformat_open_input().
1555  */
1556  int error_recognition;
1557 
1558  /**
1559  * Custom interrupt callbacks for the I/O layer.
1560  *
1561  * demuxing: set by the user before avformat_open_input().
1562  * muxing: set by the user before avformat_write_header()
1563  * (mainly useful for AVFMT_NOFILE formats). The callback
1564  * should also be passed to avio_open2() if it's used to
1565  * open the file.
1566  */
1568 
1569  /**
1570  * Flags to enable debugging.
1571  */
1572  int debug;
1573 #define FF_FDEBUG_TS 0x0001
1574 
1575  /**
1576  * Maximum buffering duration for interleaving.
1577  *
1578  * To ensure all the streams are interleaved correctly,
1579  * av_interleaved_write_frame() will wait until it has at least one packet
1580  * for each stream before actually writing any packets to the output file.
1581  * When some streams are "sparse" (i.e. there are large gaps between
1582  * successive packets), this can result in excessive buffering.
1583  *
1584  * This field specifies the maximum difference between the timestamps of the
1585  * first and the last packet in the muxing queue, above which libavformat
1586  * will output a packet regardless of whether it has queued a packet for all
1587  * the streams.
1588  *
1589  * Muxing only, set by the caller before avformat_write_header().
1590  */
1591  int64_t max_interleave_delta;
1592 
1593  /**
1594  * Allow non-standard and experimental extension
1595  * @see AVCodecContext.strict_std_compliance
1596  */
1598 
1599  /**
1600  * Flags for the user to detect events happening on the file. Flags must
1601  * be cleared by the user once the event has been handled.
1602  * A combination of AVFMT_EVENT_FLAG_*.
1603  */
1604  int event_flags;
1605 #define AVFMT_EVENT_FLAG_METADATA_UPDATED 0x0001 ///< The call resulted in updated metadata.
1606 
1607  /**
1608  * Maximum number of packets to read while waiting for the first timestamp.
1609  * Decoding only.
1610  */
1611  int max_ts_probe;
1612 
1613  /**
1614  * Avoid negative timestamps during muxing.
1615  * Any value of the AVFMT_AVOID_NEG_TS_* constants.
1616  * Note, this only works when using av_interleaved_write_frame. (interleave_packet_per_dts is in use)
1617  * - muxing: Set by user
1618  * - demuxing: unused
1619  */
1620  int avoid_negative_ts;
1621 #define AVFMT_AVOID_NEG_TS_AUTO -1 ///< Enabled when required by target format
1622 #define AVFMT_AVOID_NEG_TS_MAKE_NON_NEGATIVE 1 ///< Shift timestamps so they are non negative
1623 #define AVFMT_AVOID_NEG_TS_MAKE_ZERO 2 ///< Shift timestamps so that they start at 0
1624 
1625  /**
1626  * Transport stream id.
1627  * This will be moved into demuxer private options. Thus no API/ABI compatibility
1628  */
1629  int ts_id;
1631  /**
1632  * Audio preload in microseconds.
1633  * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1634  * - encoding: Set by user via AVOptions (NO direct access)
1635  * - decoding: unused
1636  */
1637  int audio_preload;
1638 
1639  /**
1640  * Max chunk time in microseconds.
1641  * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1642  * - encoding: Set by user via AVOptions (NO direct access)
1643  * - decoding: unused
1644  */
1645  int max_chunk_duration;
1646 
1647  /**
1648  * Max chunk size in bytes
1649  * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1650  * - encoding: Set by user via AVOptions (NO direct access)
1651  * - decoding: unused
1652  */
1653  int max_chunk_size;
1654 
1655  /**
1656  * forces the use of wallclock timestamps as pts/dts of packets
1657  * This has undefined results in the presence of B frames.
1658  * - encoding: unused
1659  * - decoding: Set by user via AVOptions (NO direct access)
1660  */
1662 
1663  /**
1664  * avio flags, used to force AVIO_FLAG_DIRECT.
1665  * - encoding: unused
1666  * - decoding: Set by user via AVOptions (NO direct access)
1667  */
1668  int avio_flags;
1669 
1670  /**
1671  * The duration field can be estimated through various ways, and this field can be used
1672  * to know how the duration was estimated.
1673  * - encoding: unused
1674  * - decoding: Read by user via AVOptions (NO direct access)
1675  */
1677 
1678  /**
1679  * Skip initial bytes when opening stream
1680  * - encoding: unused
1681  * - decoding: Set by user via AVOptions (NO direct access)
1682  */
1683  int64_t skip_initial_bytes;
1684 
1685  /**
1686  * Correct single timestamp overflows
1687  * - encoding: unused
1688  * - decoding: Set by user via AVOptions (NO direct access)
1689  */
1690  unsigned int correct_ts_overflow;
1691 
1692  /**
1693  * Force seeking to any (also non key) frames.
1694  * - encoding: unused
1695  * - decoding: Set by user via AVOptions (NO direct access)
1696  */
1697  int seek2any;
1698 
1699  /**
1700  * Flush the I/O context after each packet.
1701  * - encoding: Set by user via AVOptions (NO direct access)
1702  * - decoding: unused
1703  */
1704  int flush_packets;
1705 
1706  /**
1707  * format probing score.
1708  * The maximal score is AVPROBE_SCORE_MAX, its set when the demuxer probes
1709  * the format.
1710  * - encoding: unused
1711  * - decoding: set by avformat, read by user via av_format_get_probe_score() (NO direct access)
1712  */
1713  int probe_score;
1715  /**
1716  * number of bytes to read maximally to identify format.
1717  * - encoding: unused
1718  * - decoding: set by user through AVOPtions (NO direct access)
1719  */
1720  int format_probesize;
1721 
1722  /**
1723  * ',' separated list of allowed decoders.
1724  * If NULL then all are allowed
1725  * - encoding: unused
1726  * - decoding: set by user through AVOptions (NO direct access)
1727  */
1728  char *codec_whitelist;
1729 
1730  /**
1731  * ',' separated list of allowed demuxers.
1732  * If NULL then all are allowed
1733  * - encoding: unused
1734  * - decoding: set by user through AVOptions (NO direct access)
1735  */
1736  char *format_whitelist;
1737 
1738  /**
1739  * An opaque field for libavformat internal usage.
1740  * Must not be accessed in any way by callers.
1741  */
1742  AVFormatInternal *internal;
1743 
1744  /**
1745  * IO repositioned flag.
1746  * This is set by avformat when the underlaying IO context read pointer
1747  * is repositioned, for example when doing byte based seeking.
1748  * Demuxers can use the flag to detect such changes.
1749  */
1750  int io_repositioned;
1751 
1752  /**
1753  * Forced video codec.
1754  * This allows forcing a specific decoder, even when there are multiple with
1755  * the same codec_id.
1756  * Demuxing: Set by user via av_format_set_video_codec (NO direct access).
1757  */
1759 
1760  /**
1761  * Forced audio codec.
1762  * This allows forcing a specific decoder, even when there are multiple with
1763  * the same codec_id.
1764  * Demuxing: Set by user via av_format_set_audio_codec (NO direct access).
1765  */
1767 
1768  /**
1769  * Forced subtitle codec.
1770  * This allows forcing a specific decoder, even when there are multiple with
1771  * the same codec_id.
1772  * Demuxing: Set by user via av_format_set_subtitle_codec (NO direct access).
1773  */
1775 
1776  /**
1777  * Forced data codec.
1778  * This allows forcing a specific decoder, even when there are multiple with
1779  * the same codec_id.
1780  * Demuxing: Set by user via av_format_set_data_codec (NO direct access).
1781  */
1783 
1784  /**
1785  * Number of bytes to be written as padding in a metadata header.
1786  * Demuxing: Unused.
1787  * Muxing: Set by user via av_format_set_metadata_header_padding.
1788  */
1790 
1791  /**
1792  * User data.
1793  * This is a place for some private data of the user.
1794  */
1795  void *opaque;
1796 
1797  /**
1798  * Callback used by devices to communicate with application.
1799  */
1801 
1802  /**
1803  * Output timestamp offset, in microseconds.
1804  * Muxing: set by user via AVOptions (NO direct access)
1805  */
1806  int64_t output_ts_offset;
1807 
1808  /**
1809  * dump format separator.
1810  * can be ", " or "\n " or anything else
1811  * Code outside libavformat should access this field using AVOptions
1812  * (NO direct access).
1813  * - muxing: Set by user.
1814  * - demuxing: Set by user.
1815  */
1817 
1818  /**
1819  * Forced Data codec_id.
1820  * Demuxing: Set by user.
1821  */
1822  enum AVCodecID data_codec_id;
1823 
1824 #if FF_API_OLD_OPEN_CALLBACKS
1825  /**
1826  * Called to open further IO contexts when needed for demuxing.
1827  *
1828  * This can be set by the user application to perform security checks on
1829  * the URLs before opening them.
1830  * The function should behave like avio_open2(), AVFormatContext is provided
1831  * as contextual information and to reach AVFormatContext.opaque.
1832  *
1833  * If NULL then some simple checks are used together with avio_open2().
1834  *
1835  * Must not be accessed directly from outside avformat.
1836  * @See av_format_set_open_cb()
1837  *
1838  * Demuxing: Set by user.
1839  *
1840  * @deprecated Use io_open and io_close.
1841  */
1843  int (*open_cb)(struct AVFormatContext *s, AVIOContext **p, const char *url, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options);
1844 #endif
1845 
1846  /**
1847  * ',' separated list of allowed protocols.
1848  * - encoding: unused
1849  * - decoding: set by user through AVOptions (NO direct access)
1850  */
1851  char *protocol_whitelist;
1852 
1853  /*
1854  * A callback for opening new IO streams.
1855  *
1856  * Whenever a muxer or a demuxer needs to open an IO stream (typically from
1857  * avformat_open_input() for demuxers, but for certain formats can happen at
1858  * other times as well), it will call this callback to obtain an IO context.
1859  *
1860  * @param s the format context
1861  * @param pb on success, the newly opened IO context should be returned here
1862  * @param url the url to open
1863  * @param flags a combination of AVIO_FLAG_*
1864  * @param options a dictionary of additional options, with the same
1865  * semantics as in avio_open2()
1866  * @return 0 on success, a negative AVERROR code on failure
1867  *
1868  * @note Certain muxers and demuxers do nesting, i.e. they open one or more
1869  * additional internal format contexts. Thus the AVFormatContext pointer
1870  * passed to this callback may be different from the one facing the caller.
1871  * It will, however, have the same 'opaque' field.
1872  */
1873  int (*io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url,
1874  int flags, AVDictionary **options);
1875 
1876  /**
1877  * A callback for closing the streams opened with AVFormatContext.io_open().
1878  */
1879  void (*io_close)(struct AVFormatContext *s, AVIOContext *pb);
1880 
1881  /**
1882  * ',' separated list of disallowed protocols.
1883  * - encoding: unused
1884  * - decoding: set by user through AVOptions (NO direct access)
1885  */
1886  char *protocol_blacklist;
1887 } AVFormatContext;
1888 
1900 void * av_format_get_opaque(const AVFormatContext *s);
1904 #if FF_API_OLD_OPEN_CALLBACKS
1905 attribute_deprecated AVOpenCallback av_format_get_open_cb(const AVFormatContext *s);
1906 attribute_deprecated void av_format_set_open_cb(AVFormatContext *s, AVOpenCallback callback);
1907 #endif
1908 
1909 /**
1910  * This function will cause global side data to be injected in the next packet
1911  * of each stream as well as after any subsequent seek.
1912  */
1914 
1915 /**
1916  * Returns the method used to set ctx->duration.
1917  *
1918  * @return AVFMT_DURATION_FROM_PTS, AVFMT_DURATION_FROM_STREAM, or AVFMT_DURATION_FROM_BITRATE.
1919  */
1921 
1922 typedef struct AVPacketList {
1923  AVPacket pkt;
1924  struct AVPacketList *next;
1925 } AVPacketList;
1926 
1927 
1928 /**
1929  * @defgroup lavf_core Core functions
1930  * @ingroup libavf
1931  *
1932  * Functions for querying libavformat capabilities, allocating core structures,
1933  * etc.
1934  * @{
1935  */
1936 
1937 /**
1938  * Return the LIBAVFORMAT_VERSION_INT constant.
1939  */
1940 unsigned avformat_version(void);
1941 
1942 /**
1943  * Return the libavformat build-time configuration.
1944  */
1945 const char *avformat_configuration(void);
1946 
1947 /**
1948  * Return the libavformat license.
1949  */
1950 const char *avformat_license(void);
1951 
1952 /**
1953  * Initialize libavformat and register all the muxers, demuxers and
1954  * protocols. If you do not call this function, then you can select
1955  * exactly which formats you want to support.
1956  *
1957  * @see av_register_input_format()
1958  * @see av_register_output_format()
1959  */
1960 void av_register_all(void);
1961 
1964 
1965 /**
1966  * Do global initialization of network components. This is optional,
1967  * but recommended, since it avoids the overhead of implicitly
1968  * doing the setup for each session.
1969  *
1970  * Calling this function will become mandatory if using network
1971  * protocols at some major version bump.
1972  */
1973 int avformat_network_init(void);
1974 
1975 /**
1976  * Undo the initialization done by avformat_network_init.
1977  */
1978 int avformat_network_deinit(void);
1979 
1980 /**
1981  * If f is NULL, returns the first registered input format,
1982  * if f is non-NULL, returns the next registered input format after f
1983  * or NULL if f is the last one.
1984  */
1986 
1987 /**
1988  * If f is NULL, returns the first registered output format,
1989  * if f is non-NULL, returns the next registered output format after f
1990  * or NULL if f is the last one.
1991  */
1993 
1994 /**
1995  * Allocate an AVFormatContext.
1996  * avformat_free_context() can be used to free the context and everything
1997  * allocated by the framework within it.
1998  */
2000 
2001 /**
2002  * Free an AVFormatContext and all its streams.
2003  * @param s context to free
2004  */
2006 
2007 /**
2008  * Get the AVClass for AVFormatContext. It can be used in combination with
2009  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2010  *
2011  * @see av_opt_find().
2012  */
2013 const AVClass *avformat_get_class(void);
2014 
2015 /**
2016  * Add a new stream to a media file.
2017  *
2018  * When demuxing, it is called by the demuxer in read_header(). If the
2019  * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
2020  * be called in read_packet().
2021  *
2022  * When muxing, should be called by the user before avformat_write_header().
2023  *
2024  * User is required to call avcodec_close() and avformat_free_context() to
2025  * clean up the allocation by avformat_new_stream().
2026  *
2027  * @param s media file handle
2028  * @param c If non-NULL, the AVCodecContext corresponding to the new stream
2029  * will be initialized to use this codec. This is needed for e.g. codec-specific
2030  * defaults to be set, so codec should be provided if it is known.
2031  *
2032  * @return newly created stream or NULL on error.
2033  */
2035 
2036 /**
2037  * Allocate new information from stream.
2038  *
2039  * @param stream stream
2040  * @param type desired side information type
2041  * @param size side information size
2042  * @return pointer to fresh allocated data or NULL otherwise
2043  */
2045  enum AVPacketSideDataType type, int size);
2046 /**
2047  * Get side information from stream.
2048  *
2049  * @param stream stream
2050  * @param type desired side information type
2051  * @param size pointer for side information size to store (optional)
2052  * @return pointer to data if present or NULL otherwise
2053  */
2055  enum AVPacketSideDataType type, int *size);
2056 
2058 
2059 /**
2060  * @}
2061  */
2062 
2063 
2064 /**
2065  * Allocate an AVFormatContext for an output format.
2066  * avformat_free_context() can be used to free the context and
2067  * everything allocated by the framework within it.
2068  *
2069  * @param *ctx is set to the created format context, or to NULL in
2070  * case of failure
2071  * @param oformat format to use for allocating the context, if NULL
2072  * format_name and filename are used instead
2073  * @param format_name the name of output format to use for allocating the
2074  * context, if NULL filename is used instead
2075  * @param filename the name of the filename to use for allocating the
2076  * context, may be NULL
2077  * @return >= 0 in case of success, a negative AVERROR code in case of
2078  * failure
2079  */
2081  const char *format_name, const char *filename);
2082 
2083 /**
2084  * @addtogroup lavf_decoding
2085  * @{
2086  */
2087 
2088 /**
2089  * Find AVInputFormat based on the short name of the input format.
2090  */
2091 AVInputFormat *av_find_input_format(const char *short_name);
2092 
2093 /**
2094  * Guess the file format.
2095  *
2096  * @param pd data to be probed
2097  * @param is_opened Whether the file is already opened; determines whether
2098  * demuxers with or without AVFMT_NOFILE are probed.
2099  */
2100 AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
2101 
2102 /**
2103  * Guess the file format.
2104  *
2105  * @param pd data to be probed
2106  * @param is_opened Whether the file is already opened; determines whether
2107  * demuxers with or without AVFMT_NOFILE are probed.
2108  * @param score_max A probe score larger that this is required to accept a
2109  * detection, the variable is set to the actual detection
2110  * score afterwards.
2111  * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
2112  * to retry with a larger probe buffer.
2113  */
2114 AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max);
2115 
2116 /**
2117  * Guess the file format.
2118  *
2119  * @param is_opened Whether the file is already opened; determines whether
2120  * demuxers with or without AVFMT_NOFILE are probed.
2121  * @param score_ret The score of the best detection.
2122  */
2123 AVInputFormat *av_probe_input_format3(AVProbeData *pd, int is_opened, int *score_ret);
2124 
2125 /**
2126  * Probe a bytestream to determine the input format. Each time a probe returns
2127  * with a score that is too low, the probe buffer size is increased and another
2128  * attempt is made. When the maximum probe size is reached, the input format
2129  * with the highest score is returned.
2130  *
2131  * @param pb the bytestream to probe
2132  * @param fmt the input format is put here
2133  * @param url the url of the stream
2134  * @param logctx the log context
2135  * @param offset the offset within the bytestream to probe from
2136  * @param max_probe_size the maximum probe buffer size (zero for default)
2137  * @return the score in case of success, a negative value corresponding to an
2138  * the maximal score is AVPROBE_SCORE_MAX
2139  * AVERROR code otherwise
2140  */
2142  const char *url, void *logctx,
2143  unsigned int offset, unsigned int max_probe_size);
2144 
2145 /**
2146  * Like av_probe_input_buffer2() but returns 0 on success
2147  */
2149  const char *url, void *logctx,
2150  unsigned int offset, unsigned int max_probe_size);
2151 
2152 /**
2153  * Open an input stream and read the header. The codecs are not opened.
2154  * The stream must be closed with avformat_close_input().
2155  *
2156  * @param ps Pointer to user-supplied AVFormatContext (allocated by avformat_alloc_context).
2157  * May be a pointer to NULL, in which case an AVFormatContext is allocated by this
2158  * function and written into ps.
2159  * Note that a user-supplied AVFormatContext will be freed on failure.
2160  * @param url URL of the stream to open.
2161  * @param fmt If non-NULL, this parameter forces a specific input format.
2162  * Otherwise the format is autodetected.
2163  * @param options A dictionary filled with AVFormatContext and demuxer-private options.
2164  * On return this parameter will be destroyed and replaced with a dict containing
2165  * options that were not found. May be NULL.
2166  *
2167  * @return 0 on success, a negative AVERROR on failure.
2168  *
2169  * @note If you want to use custom IO, preallocate the format context and set its pb field.
2170  */
2172 
2175 
2176 /**
2177  * Read packets of a media file to get stream information. This
2178  * is useful for file formats with no headers such as MPEG. This
2179  * function also computes the real framerate in case of MPEG-2 repeat
2180  * frame mode.
2181  * The logical file position is not changed by this function;
2182  * examined packets may be buffered for later processing.
2183  *
2184  * @param ic media file handle
2185  * @param options If non-NULL, an ic.nb_streams long array of pointers to
2186  * dictionaries, where i-th member contains options for
2187  * codec corresponding to i-th stream.
2188  * On return each dictionary will be filled with options that were not found.
2189  * @return >=0 if OK, AVERROR_xxx on error
2190  *
2191  * @note this function isn't guaranteed to open all the codecs, so
2192  * options being non-empty at return is a perfectly normal behavior.
2193  *
2194  * @todo Let the user decide somehow what information is needed so that
2195  * we do not waste time getting stuff the user does not need.
2196  */
2198 
2199 /**
2200  * Find the programs which belong to a given stream.
2201  *
2202  * @param ic media file handle
2203  * @param last the last found program, the search will start after this
2204  * program, or from the beginning if it is NULL
2205  * @param s stream index
2206  * @return the next program which belongs to s, NULL if no program is found or
2207  * the last program is not among the programs of ic.
2208  */
2210 
2211 void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx);
2212 
2213 /**
2214  * Find the "best" stream in the file.
2215  * The best stream is determined according to various heuristics as the most
2216  * likely to be what the user expects.
2217  * If the decoder parameter is non-NULL, av_find_best_stream will find the
2218  * default decoder for the stream's codec; streams for which no decoder can
2219  * be found are ignored.
2220  *
2221  * @param ic media file handle
2222  * @param type stream type: video, audio, subtitles, etc.
2223  * @param wanted_stream_nb user-requested stream number,
2224  * or -1 for automatic selection
2225  * @param related_stream try to find a stream related (eg. in the same
2226  * program) to this one, or -1 if none
2227  * @param decoder_ret if non-NULL, returns the decoder for the
2228  * selected stream
2229  * @param flags flags; none are currently defined
2230  * @return the non-negative stream number in case of success,
2231  * AVERROR_STREAM_NOT_FOUND if no stream with the requested type
2232  * could be found,
2233  * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
2234  * @note If av_find_best_stream returns successfully and decoder_ret is not
2235  * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
2236  */
2238  enum AVMediaType type,
2239  int wanted_stream_nb,
2240  int related_stream,
2241  AVCodec **decoder_ret,
2242  int flags);
2243 
2244 /**
2245  * Return the next frame of a stream.
2246  * This function returns what is stored in the file, and does not validate
2247  * that what is there are valid frames for the decoder. It will split what is
2248  * stored in the file into frames and return one for each call. It will not
2249  * omit invalid data between valid frames so as to give the decoder the maximum
2250  * information possible for decoding.
2251  *
2252  * If pkt->buf is NULL, then the packet is valid until the next
2253  * av_read_frame() or until avformat_close_input(). Otherwise the packet
2254  * is valid indefinitely. In both cases the packet must be freed with
2255  * av_packet_unref when it is no longer needed. For video, the packet contains
2256  * exactly one frame. For audio, it contains an integer number of frames if each
2257  * frame has a known fixed size (e.g. PCM or ADPCM data). If the audio frames
2258  * have a variable size (e.g. MPEG audio), then it contains one frame.
2259  *
2260  * pkt->pts, pkt->dts and pkt->duration are always set to correct
2261  * values in AVStream.time_base units (and guessed if the format cannot
2262  * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
2263  * has B-frames, so it is better to rely on pkt->dts if you do not
2264  * decompress the payload.
2265  *
2266  * @return 0 if OK, < 0 on error or end of file
2267  */
2269 
2270 /**
2271  * Seek to the keyframe at timestamp.
2272  * 'timestamp' in 'stream_index'.
2273  *
2274  * @param s media file handle
2275  * @param stream_index If stream_index is (-1), a default
2276  * stream is selected, and timestamp is automatically converted
2277  * from AV_TIME_BASE units to the stream specific time_base.
2278  * @param timestamp Timestamp in AVStream.time_base units
2279  * or, if no stream is specified, in AV_TIME_BASE units.
2280  * @param flags flags which select direction and seeking mode
2281  * @return >= 0 on success
2282  */
2283 int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
2284  int flags);
2285 
2286 /**
2287  * Seek to timestamp ts.
2288  * Seeking will be done so that the point from which all active streams
2289  * can be presented successfully will be closest to ts and within min/max_ts.
2290  * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
2291  *
2292  * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
2293  * are the file position (this may not be supported by all demuxers).
2294  * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
2295  * in the stream with stream_index (this may not be supported by all demuxers).
2296  * Otherwise all timestamps are in units of the stream selected by stream_index
2297  * or if stream_index is -1, in AV_TIME_BASE units.
2298  * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
2299  * keyframes (this may not be supported by all demuxers).
2300  * If flags contain AVSEEK_FLAG_BACKWARD, it is ignored.
2301  *
2302  * @param s media file handle
2303  * @param stream_index index of the stream which is used as time base reference
2304  * @param min_ts smallest acceptable timestamp
2305  * @param ts target timestamp
2306  * @param max_ts largest acceptable timestamp
2307  * @param flags flags
2308  * @return >=0 on success, error code otherwise
2309  *
2310  * @note This is part of the new seek API which is still under construction.
2311  * Thus do not use this yet. It may change at any time, do not expect
2312  * ABI compatibility yet!
2313  */
2314 int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
2315 
2316 /**
2317  * Discard all internally buffered data. This can be useful when dealing with
2318  * discontinuities in the byte stream. Generally works only with formats that
2319  * can resync. This includes headerless formats like MPEG-TS/TS but should also
2320  * work with NUT, Ogg and in a limited way AVI for example.
2321  *
2322  * The set of streams, the detected duration, stream parameters and codecs do
2323  * not change when calling this function. If you want a complete reset, it's
2324  * better to open a new AVFormatContext.
2325  *
2326  * This does not flush the AVIOContext (s->pb). If necessary, call
2327  * avio_flush(s->pb) before calling this function.
2328  *
2329  * @param s media file handle
2330  * @return >=0 on success, error code otherwise
2331  */
2333 
2334 /**
2335  * Start playing a network-based stream (e.g. RTSP stream) at the
2336  * current position.
2337  */
2339 
2340 /**
2341  * Pause a network-based stream (e.g. RTSP stream).
2342  *
2343  * Use av_read_play() to resume it.
2344  */
2346 
2347 /**
2348  * Close an opened input AVFormatContext. Free it and all its contents
2349  * and set *s to NULL.
2350  */
2352 /**
2353  * @}
2354  */
2355 
2356 #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
2357 #define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
2358 #define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
2359 #define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
2360 
2361 /**
2362  * @addtogroup lavf_encoding
2363  * @{
2364  */
2365 /**
2366  * Allocate the stream private data and write the stream header to
2367  * an output media file.
2368  *
2369  * @param s Media file handle, must be allocated with avformat_alloc_context().
2370  * Its oformat field must be set to the desired output format;
2371  * Its pb field must be set to an already opened AVIOContext.
2372  * @param options An AVDictionary filled with AVFormatContext and muxer-private options.
2373  * On return this parameter will be destroyed and replaced with a dict containing
2374  * options that were not found. May be NULL.
2375  *
2376  * @return 0 on success, negative AVERROR on failure.
2377  *
2378  * @see av_opt_find, av_dict_set, avio_open, av_oformat_next.
2379  */
2382 
2383 /**
2384  * Write a packet to an output media file.
2385  *
2386  * This function passes the packet directly to the muxer, without any buffering
2387  * or reordering. The caller is responsible for correctly interleaving the
2388  * packets if the format requires it. Callers that want libavformat to handle
2389  * the interleaving should call av_interleaved_write_frame() instead of this
2390  * function.
2391  *
2392  * @param s media file handle
2393  * @param pkt The packet containing the data to be written. Note that unlike
2394  * av_interleaved_write_frame(), this function does not take
2395  * ownership of the packet passed to it (though some muxers may make
2396  * an internal reference to the input packet).
2397  * <br>
2398  * This parameter can be NULL (at any time, not just at the end), in
2399  * order to immediately flush data buffered within the muxer, for
2400  * muxers that buffer up data internally before writing it to the
2401  * output.
2402  * <br>
2403  * Packet's @ref AVPacket.stream_index "stream_index" field must be
2404  * set to the index of the corresponding stream in @ref
2405  * AVFormatContext.streams "s->streams".
2406  * <br>
2407  * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2408  * must be set to correct values in the stream's timebase (unless the
2409  * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2410  * they can be set to AV_NOPTS_VALUE).
2411  * The dts for subsequent packets passed to this function must be strictly
2412  * increasing when compared in their respective timebases (unless the
2413  * output format is flagged with the AVFMT_TS_NONSTRICT, then they
2414  * merely have to be nondecreasing). @ref AVPacket.duration
2415  * "duration") should also be set if known.
2416  * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush
2417  *
2418  * @see av_interleaved_write_frame()
2419  */
2421 
2422 /**
2423  * Write a packet to an output media file ensuring correct interleaving.
2424  *
2425  * This function will buffer the packets internally as needed to make sure the
2426  * packets in the output file are properly interleaved in the order of
2427  * increasing dts. Callers doing their own interleaving should call
2428  * av_write_frame() instead of this function.
2429  *
2430  * Using this function instead of av_write_frame() can give muxers advance
2431  * knowledge of future packets, improving e.g. the behaviour of the mp4
2432  * muxer for VFR content in fragmenting mode.
2433  *
2434  * @param s media file handle
2435  * @param pkt The packet containing the data to be written.
2436  * <br>
2437  * If the packet is reference-counted, this function will take
2438  * ownership of this reference and unreference it later when it sees
2439  * fit.
2440  * The caller must not access the data through this reference after
2441  * this function returns. If the packet is not reference-counted,
2442  * libavformat will make a copy.
2443  * <br>
2444  * This parameter can be NULL (at any time, not just at the end), to
2445  * flush the interleaving queues.
2446  * <br>
2447  * Packet's @ref AVPacket.stream_index "stream_index" field must be
2448  * set to the index of the corresponding stream in @ref
2449  * AVFormatContext.streams "s->streams".
2450  * <br>
2451  * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2452  * must be set to correct values in the stream's timebase (unless the
2453  * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2454  * they can be set to AV_NOPTS_VALUE).
2455  * The dts for subsequent packets in one stream must be strictly
2456  * increasing (unless the output format is flagged with the
2457  * AVFMT_TS_NONSTRICT, then they merely have to be nondecreasing).
2458  * @ref AVPacket.duration "duration") should also be set if known.
2459  *
2460  * @return 0 on success, a negative AVERROR on error. Libavformat will always
2461  * take care of freeing the packet, even if this function fails.
2462  *
2463  * @see av_write_frame(), AVFormatContext.max_interleave_delta
2464  */
2466 
2467 /**
2468  * Write an uncoded frame to an output media file.
2469  *
2470  * The frame must be correctly interleaved according to the container
2471  * specification; if not, then av_interleaved_write_frame() must be used.
2472  *
2473  * See av_interleaved_write_frame() for details.
2474  */
2475 int av_write_uncoded_frame(AVFormatContext *s, int stream_index,
2476  AVFrame *frame);
2477 
2478 /**
2479  * Write an uncoded frame to an output media file.
2480  *
2481  * If the muxer supports it, this function makes it possible to write an AVFrame
2482  * structure directly, without encoding it into a packet.
2483  * It is mostly useful for devices and similar special muxers that use raw
2484  * video or PCM data and will not serialize it into a byte stream.
2485  *
2486  * To test whether it is possible to use it with a given muxer and stream,
2487  * use av_write_uncoded_frame_query().
2488  *
2489  * The caller gives up ownership of the frame and must not access it
2490  * afterwards.
2491  *
2492  * @return >=0 for success, a negative code on error
2493  */
2494 int av_interleaved_write_uncoded_frame(AVFormatContext *s, int stream_index,
2495  AVFrame *frame);
2496 
2497 /**
2498  * Test whether a muxer supports uncoded frame.
2499  *
2500  * @return >=0 if an uncoded frame can be written to that muxer and stream,
2501  * <0 if not
2502  */
2503 int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index);
2504 
2505 /**
2506  * Write the stream trailer to an output media file and free the
2507  * file private data.
2508  *
2509  * May only be called after a successful call to avformat_write_header.
2510  *
2511  * @param s media file handle
2512  * @return 0 if OK, AVERROR_xxx on error
2513  */
2515 
2516 /**
2517  * Return the output format in the list of registered output formats
2518  * which best matches the provided parameters, or return NULL if
2519  * there is no match.
2520  *
2521  * @param short_name if non-NULL checks if short_name matches with the
2522  * names of the registered formats
2523  * @param filename if non-NULL checks if filename terminates with the
2524  * extensions of the registered formats
2525  * @param mime_type if non-NULL checks if mime_type matches with the
2526  * MIME type of the registered formats
2527  */
2528 AVOutputFormat *av_guess_format(const char *short_name,
2529  const char *filename,
2530  const char *mime_type);
2531 
2532 /**
2533  * Guess the codec ID based upon muxer and filename.
2534  */
2535 enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
2536  const char *filename, const char *mime_type,
2537  enum AVMediaType type);
2538 
2539 /**
2540  * Get timing information for the data currently output.
2541  * The exact meaning of "currently output" depends on the format.
2542  * It is mostly relevant for devices that have an internal buffer and/or
2543  * work in real time.
2544  * @param s media file handle
2545  * @param stream stream in the media file
2546  * @param[out] dts DTS of the last packet output for the stream, in stream
2547  * time_base units
2548  * @param[out] wall absolute time when that packet whas output,
2549  * in microsecond
2550  * @return 0 if OK, AVERROR(ENOSYS) if the format does not support it
2551  * Note: some formats or devices may not allow to measure dts and wall
2552  * atomically.
2553  */
2554 int av_get_output_timestamp(struct AVFormatContext *s, int stream,
2555  int64_t *dts, int64_t *wall);
2556 
2557 
2558 /**
2559  * @}
2560  */
2561 
2562 
2563 /**
2564  * @defgroup lavf_misc Utility functions
2565  * @ingroup libavf
2566  * @{
2567  *
2568  * Miscellaneous utility functions related to both muxing and demuxing
2569  * (or neither).
2570  */
2571 
2572 /**
2573  * Send a nice hexadecimal dump of a buffer to the specified file stream.
2574  *
2575  * @param f The file stream pointer where the dump should be sent to.
2576  * @param buf buffer
2577  * @param size buffer size
2578  *
2579  * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2
2580  */
2581 void av_hex_dump(FILE *f, const uint8_t *buf, int size);
2582 
2583 /**
2584  * Send a nice hexadecimal dump of a buffer to the log.
2585  *
2586  * @param avcl A pointer to an arbitrary struct of which the first field is a
2587  * pointer to an AVClass struct.
2588  * @param level The importance level of the message, lower values signifying
2589  * higher importance.
2590  * @param buf buffer
2591  * @param size buffer size
2592  *
2593  * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2
2594  */
2595 void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size);
2596 
2597 /**
2598  * Send a nice dump of a packet to the specified file stream.
2599  *
2600  * @param f The file stream pointer where the dump should be sent to.
2601  * @param pkt packet to dump
2602  * @param dump_payload True if the payload must be displayed, too.
2603  * @param st AVStream that the packet belongs to
2604  */
2605 void av_pkt_dump2(FILE *f, const AVPacket *pkt, int dump_payload, const AVStream *st);
2606 
2607 
2608 /**
2609  * Send a nice dump of a packet to the log.
2610  *
2611  * @param avcl A pointer to an arbitrary struct of which the first field is a
2612  * pointer to an AVClass struct.
2613  * @param level The importance level of the message, lower values signifying
2614  * higher importance.
2615  * @param pkt packet to dump
2616  * @param dump_payload True if the payload must be displayed, too.
2617  * @param st AVStream that the packet belongs to
2618  */
2619 void av_pkt_dump_log2(void *avcl, int level, const AVPacket *pkt, int dump_payload,
2620  const AVStream *st);
2621 
2622 /**
2623  * Get the AVCodecID for the given codec tag tag.
2624  * If no codec id is found returns AV_CODEC_ID_NONE.
2625  *
2626  * @param tags list of supported codec_id-codec_tag pairs, as stored
2627  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2628  * @param tag codec tag to match to a codec ID
2629  */
2630 enum AVCodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
2631 
2632 /**
2633  * Get the codec tag for the given codec id id.
2634  * If no codec tag is found returns 0.
2635  *
2636  * @param tags list of supported codec_id-codec_tag pairs, as stored
2637  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2638  * @param id codec ID to match to a codec tag
2639  */
2640 unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id);
2641 
2642 /**
2643  * Get the codec tag for the given codec id.
2644  *
2645  * @param tags list of supported codec_id - codec_tag pairs, as stored
2646  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2647  * @param id codec id that should be searched for in the list
2648  * @param tag A pointer to the found tag
2649  * @return 0 if id was not found in tags, > 0 if it was found
2650  */
2651 int av_codec_get_tag2(const struct AVCodecTag * const *tags, enum AVCodecID id,
2652  unsigned int *tag);
2653 
2655 
2656 /**
2657  * Get the index for a specific timestamp.
2658  *
2659  * @param st stream that the timestamp belongs to
2660  * @param timestamp timestamp to retrieve the index for
2661  * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
2662  * to the timestamp which is <= the requested one, if backward
2663  * is 0, then it will be >=
2664  * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
2665  * @return < 0 if no such timestamp could be found
2666  */
2667 int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
2668 
2669 /**
2670  * Add an index entry into a sorted list. Update the entry if the list
2671  * already contains it.
2672  *
2673  * @param timestamp timestamp in the time base of the given stream
2674  */
2675 int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
2676  int size, int distance, int flags);
2677 
2678 
2679 /**
2680  * Split a URL string into components.
2681  *
2682  * The pointers to buffers for storing individual components may be null,
2683  * in order to ignore that component. Buffers for components not found are
2684  * set to empty strings. If the port is not found, it is set to a negative
2685  * value.
2686  *
2687  * @param proto the buffer for the protocol
2688  * @param proto_size the size of the proto buffer
2689  * @param authorization the buffer for the authorization
2690  * @param authorization_size the size of the authorization buffer
2691  * @param hostname the buffer for the host name
2692  * @param hostname_size the size of the hostname buffer
2693  * @param port_ptr a pointer to store the port number in
2694  * @param path the buffer for the path
2695  * @param path_size the size of the path buffer
2696  * @param url the URL to split
2697  */
2698 void av_url_split(char *proto, int proto_size,
2699  char *authorization, int authorization_size,
2700  char *hostname, int hostname_size,
2701  int *port_ptr,
2702  char *path, int path_size,
2703  const char *url);
2704 
2705 
2706 /**
2707  * Print detailed information about the input or output format, such as
2708  * duration, bitrate, streams, container, programs, metadata, side data,
2709  * codec and time base.
2710  *
2711  * @param ic the context to analyze
2712  * @param index index of the stream to dump information about
2713  * @param url the URL to print, such as source or destination file
2714  * @param is_output Select whether the specified context is an input(0) or output(1)
2715  */
2717  int index,
2718  const char *url,
2719  int is_output);
2720 
2721 /**
2722  * Return in 'buf' the path with '%d' replaced by a number.
2723  *
2724  * Also handles the '%0nd' format where 'n' is the total number
2725  * of digits and '%%'.
2726  *
2727  * @param buf destination buffer
2728  * @param buf_size destination buffer size
2729  * @param path numbered sequence string
2730  * @param number frame number
2731  * @return 0 if OK, -1 on format error
2732  */
2733 int av_get_frame_filename(char *buf, int buf_size,
2734  const char *path, int number);
2735 
2736 /**
2737  * Check whether filename actually is a numbered sequence generator.
2738  *
2739  * @param filename possible numbered sequence string
2740  * @return 1 if a valid numbered sequence string, 0 otherwise
2741  */
2742 int av_filename_number_test(const char *filename);
2743 
2744 /**
2745  * Generate an SDP for an RTP session.
2746  *
2747  * Note, this overwrites the id values of AVStreams in the muxer contexts
2748  * for getting unique dynamic payload types.
2749  *
2750  * @param ac array of AVFormatContexts describing the RTP streams. If the
2751  * array is composed by only one context, such context can contain
2752  * multiple AVStreams (one AVStream per RTP stream). Otherwise,
2753  * all the contexts in the array (an AVCodecContext per RTP stream)
2754  * must contain only one AVStream.
2755  * @param n_files number of AVCodecContexts contained in ac
2756  * @param buf buffer where the SDP will be stored (must be allocated by
2757  * the caller)
2758  * @param size the size of the buffer
2759  * @return 0 if OK, AVERROR_xxx on error
2760  */
2761 int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size);
2762 
2763 /**
2764  * Return a positive value if the given filename has one of the given
2765  * extensions, 0 otherwise.
2766  *
2767  * @param filename file name to check against the given extensions
2768  * @param extensions a comma-separated list of filename extensions
2769  */
2770 int av_match_ext(const char *filename, const char *extensions);
2771 
2772 /**
2773  * Test if the given container can store a codec.
2774  *
2775  * @param ofmt container to check for compatibility
2776  * @param codec_id codec to potentially store in container
2777  * @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
2778  *
2779  * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
2780  * A negative number if this information is not available.
2781  */
2783  int std_compliance);
2784 
2785 /**
2786  * @defgroup riff_fourcc RIFF FourCCs
2787  * @{
2788  * Get the tables mapping RIFF FourCCs to libavcodec AVCodecIDs. The tables are
2789  * meant to be passed to av_codec_get_id()/av_codec_get_tag() as in the
2790  * following code:
2791  * @code
2792  * uint32_t tag = MKTAG('H', '2', '6', '4');
2793  * const struct AVCodecTag *table[] = { avformat_get_riff_video_tags(), 0 };
2794  * enum AVCodecID id = av_codec_get_id(table, tag);
2795  * @endcode
2796  */
2797 /**
2798  * @return the table mapping RIFF FourCCs for video to libavcodec AVCodecID.
2799  */
2800 const struct AVCodecTag *avformat_get_riff_video_tags(void);
2801 /**
2802  * @return the table mapping RIFF FourCCs for audio to AVCodecID.
2803  */
2804 const struct AVCodecTag *avformat_get_riff_audio_tags(void);
2805 /**
2806  * @return the table mapping MOV FourCCs for video to libavcodec AVCodecID.
2807  */
2808 const struct AVCodecTag *avformat_get_mov_video_tags(void);
2809 /**
2810  * @return the table mapping MOV FourCCs for audio to AVCodecID.
2811  */
2812 const struct AVCodecTag *avformat_get_mov_audio_tags(void);
2813 
2814 /**
2815  * @}
2816  */
2817 
2818 /**
2819  * Guess the sample aspect ratio of a frame, based on both the stream and the
2820  * frame aspect ratio.
2821  *
2822  * Since the frame aspect ratio is set by the codec but the stream aspect ratio
2823  * is set by the demuxer, these two may not be equal. This function tries to
2824  * return the value that you should use if you would like to display the frame.
2825  *
2826  * Basic logic is to use the stream aspect ratio if it is set to something sane
2827  * otherwise use the frame aspect ratio. This way a container setting, which is
2828  * usually easy to modify can override the coded value in the frames.
2829  *
2830  * @param format the format context which the stream is part of
2831  * @param stream the stream which the frame is part of
2832  * @param frame the frame with the aspect ratio to be determined
2833  * @return the guessed (valid) sample_aspect_ratio, 0/1 if no idea
2834  */
2836 
2837 /**
2838  * Guess the frame rate, based on both the container and codec information.
2839  *
2840  * @param ctx the format context which the stream is part of
2841  * @param stream the stream which the frame is part of
2842  * @param frame the frame for which the frame rate should be determined, may be NULL
2843  * @return the guessed (valid) frame rate, 0/1 if no idea
2844  */
2846 
2847 /**
2848  * Check if the stream st contained in s is matched by the stream specifier
2849  * spec.
2850  *
2851  * See the "stream specifiers" chapter in the documentation for the syntax
2852  * of spec.
2853  *
2854  * @return >0 if st is matched by spec;
2855  * 0 if st is not matched by spec;
2856  * AVERROR code if spec is invalid
2857  *
2858  * @note A stream specifier can match several streams in the format.
2859  */
2861  const char *spec);
2862 
2864 
2865 /**
2866  * Apply a list of bitstream filters to a packet.
2867  *
2868  * @param codec AVCodecContext, usually from an AVStream
2869  * @param pkt the packet to apply filters to. If, on success, the returned
2870  * packet has size == 0 and side_data_elems == 0, it indicates that
2871  * the packet should be dropped
2872  * @param bsfc a NULL-terminated list of filters to apply
2873  * @return >=0 on success;
2874  * AVERROR code on failure
2875  */
2876 #if FF_API_OLD_BSF
2878 int av_apply_bitstream_filters(AVCodecContext *codec, AVPacket *pkt,
2879  AVBitStreamFilterContext *bsfc);
2880 #endif
2881 
2882 /**
2883  * @}
2884  */
2885 
2886 #endif /* AVFORMAT_AVFORMAT_H */
unsigned int nb_chapters
Number of chapters in AVChapter array.
Definition: avformat.h:1528
unsigned int max_index_size
Maximum amount of memory in bytes to use for the index of each stream.
Definition: avformat.h:1509
void av_url_split(char *proto, int proto_size, char *authorization, int authorization_size, char *hostname, int hostname_size, int *port_ptr, char *path, int path_size, const char *url)
Split a URL string into components.
Definition: utils.c:4373
int64_t interleaver_chunk_size
Definition: avformat.h:1099
int64_t probesize
Maximum size of the data read from input for determining the input container format.
Definition: avformat.h:1465
unsigned int packet_size
Definition: avformat.h:1429
int64_t first_dts
Timestamp corresponding to the last dts sync point.
Definition: avformat.h:1047
full parsing and interpolation of timestamps for frames not starting on a packet boundary ...
Definition: avformat.h:808
const char const char void * val
Definition: avisynth_c.h:634
int64_t duration_gcd
Definition: avformat.h:1011
int audio_preload
Audio preload in microseconds.
Definition: avformat.h:1647
const char * s
Definition: avisynth_c.h:631
Bytestream IO Context.
Definition: avio.h:147
enum AVCodecID codec_id
Definition: ffmpeg_vaapi.c:149
void av_pkt_dump2(FILE *f, const AVPacket *pkt, int dump_payload, const AVStream *st)
Send a nice dump of a packet to the specified file stream.
Definition: dump.c:107
AVProbeData probe_data
Definition: avformat.h:1070
Buffered I/O operations.
AVPacketSideDataType
Definition: avcodec.h:1349
int64_t start_time_realtime
Start time of the stream in real world time, in microseconds since the Unix epoch (00:00 1st January ...
Definition: avformat.h:1552
attribute_deprecated int av_demuxer_open(AVFormatContext *ic)
Definition: utils.c:340
char * recommended_encoder_configuration
String containing paris of key and values describing recommended encoder configuration.
Definition: avformat.h:1202
This structure describes decoded (raw) audio or video data.
Definition: frame.h:184
int64_t(* read_timestamp)(struct AVFormatContext *s, int stream_index, int64_t *pos, int64_t pos_limit)
Get the next timestamp in stream[stream_index].time_base units.
Definition: avformat.h:759
AVCodec * av_format_get_video_codec(const AVFormatContext *s)
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file ensuring correct interleaving.
Definition: mux.c:1138
AVIOInterruptCB interrupt_callback
Custom interrupt callbacks for the I/O layer.
Definition: avformat.h:1577
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
static void flush(AVCodecContext *avctx)
int(* init)(struct AVFormatContext *)
Initialize format.
Definition: avformat.h:630
int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp, int size, int distance, int flags)
Add an index entry into a sorted list.
Definition: utils.c:1909
int flush_packets
Flush the I/O context after each packet.
Definition: avformat.h:1714
enum AVCodecID id
Definition: mxfenc.c:104
int av_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file.
Definition: mux.c:871
const char * fmt
Definition: avisynth_c.h:632
enum AVDurationEstimationMethod duration_estimation_method
The duration field can be estimated through various ways, and this field can be used to know how the ...
Definition: avformat.h:1686
int64_t start_skip_samples
If not 0, the number of samples that should be skipped from the start of the stream (the samples are ...
Definition: avformat.h:1128
void(* deinit)(struct AVFormatContext *)
Deinitialize format.
Definition: avformat.h:639
const char * filename
Definition: avformat.h:460
int64_t pts_buffer[MAX_REORDER_DELAY+1]
Definition: avformat.h:1072
unsigned int max_picture_buffer
Maximum amount of memory in bytes to use for buffering frames obtained from realtime capture devices...
Definition: avformat.h:1515
int64_t pos
Definition: avformat.h:816
int probe_packets
Number of packets to buffer for codec probing.
Definition: avformat.h:1055
int event_flags
Flags for the user to detect events happening on the stream.
Definition: avformat.h:994
struct FFFrac * priv_pts
Definition: avformat.h:1211
AVRational av_guess_sample_aspect_ratio(AVFormatContext *format, AVStream *stream, AVFrame *frame)
Guess the sample aspect ratio of a frame, based on both the stream and the frame aspect ratio...
Definition: utils.c:4668
enum AVCodecID video_codec
default video codec
Definition: avformat.h:533
int64_t first_discard_sample
If not 0, the first audio sample that should be discarded from the stream.
Definition: avformat.h:1136
void av_stream_set_r_frame_rate(AVStream *s, AVRational r)
int64_t pts_wrap_reference
Internal data to check for wrapping of the time stamp.
Definition: avformat.h:1160
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:943
uint8_t * dump_separator
dump format separator.
Definition: avformat.h:1826
int index
stream index in AVFormatContext
Definition: avformat.h:877
int avio_flags
avio flags, used to force AVIO_FLAG_DIRECT.
Definition: avformat.h:1678
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1074
int(* check_bitstream)(struct AVFormatContext *, const AVPacket *pkt)
Set up any necessary bitstream filtering and extract any extra data needed for the global header...
Definition: avformat.h:645
int(* free_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps)
Free device capabilities submodule.
Definition: avformat.h:621
int64_t bit_rate
Total stream bitrate in bit/s, 0 if not available.
Definition: avformat.h:1427
uint8_t * av_stream_get_side_data(AVStream *stream, enum AVPacketSideDataType type, int *size)
Get side information from stream.
Definition: utils.c:5005
int event_flags
Flags for the user to detect events happening on the file.
Definition: avformat.h:1614
int av_get_output_timestamp(struct AVFormatContext *s, int stream, int64_t *dts, int64_t *wall)
Get timing information for the data currently output.
Definition: mux.c:1258
void * priv_data
Definition: avformat.h:891
AVInputFormat * av_probe_input_format3(AVProbeData *pd, int is_opened, int *score_ret)
Guess the file format.
Definition: format.c:173
int(* write_packet)(struct AVFormatContext *, AVPacket *pkt)
Write a packet.
Definition: avformat.h:573
AVPacketSideData * side_data
An array of side data that applies to the whole stream (i.e.
Definition: avformat.h:983
static AVPacket pkt
int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index)
Test whether a muxer supports uncoded frame.
Definition: mux.c:1335
int priv_data_size
Size of private data so that it can be allocated in the wrapper.
Definition: avformat.h:711
int ctx_flags
Flags signalling stream properties.
Definition: avformat.h:1374
AVDictionary * metadata
Definition: avformat.h:1286
enum AVCodecID subtitle_codec_id
Forced subtitle codec_id.
Definition: avformat.h:1497
AVCodec.
Definition: avcodec.h:3559
int strict_std_compliance
Allow non-standard and experimental extension.
Definition: avformat.h:1607
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3931
void av_format_set_subtitle_codec(AVFormatContext *s, AVCodec *c)
enum AVDurationEstimationMethod av_fmt_ctx_get_duration_estimation_method(const AVFormatContext *ctx)
Returns the method used to set ctx->duration.
Definition: options.c:150
struct AVStream::@178 * info
int64_t last_dts_for_order_check
Internal data to analyze DTS and detect faulty mpeg streams.
Definition: avformat.h:1188
Format I/O context.
Definition: avformat.h:1325
int64_t output_ts_offset
Output timestamp offset, in microseconds.
Definition: avformat.h:1816
AVRational av_guess_frame_rate(AVFormatContext *ctx, AVStream *stream, AVFrame *frame)
Guess the frame rate, based on both the container and codec information.
Definition: utils.c:4691
unsigned int nb_stream_indexes
Definition: avformat.h:1257
int64_t cur_dts
Definition: avformat.h:1048
const struct AVCodecTag * avformat_get_mov_audio_tags(void)
Definition: isom.c:627
Public dictionary API.
int flags
Definition: avformat.h:1254
int(* read_close)(struct AVFormatContext *)
Close the stream.
Definition: avformat.h:742
int flags
can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS, AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH, AVFMT_TS_NONSTRICT, AVFMT_TS_NEGATIVE
Definition: avformat.h:541
uint8_t
int stream_identifier
Stream Identifier This is the MPEG-TS stream identifier +1 0 means unknown.
Definition: avformat.h:1097
const struct AVCodecTag * avformat_get_riff_video_tags(void)
Definition: riff.c:533
int flags
Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS, AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH, AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK, AVFMT_SEEK_TO_PTS.
Definition: avformat.h:674
enum AVCodecID av_codec_get_id(const struct AVCodecTag *const *tags, unsigned int tag)
Get the AVCodecID for the given codec tag tag.
unsigned avformat_version(void)
Return the LIBAVFORMAT_VERSION_INT constant.
Definition: utils.c:63
const char * avformat_license(void)
Return the libavformat license.
Definition: utils.c:74
int(* free_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps)
Free device capabilities submodule.
Definition: avformat.h:798
AVPacket pkt
Definition: avformat.h:1933
int priv_data_size
size of private data so that it can be allocated in the wrapper
Definition: avformat.h:563
The exact value of the fractional number is: 'val + num / den'.
Definition: internal.h:61
int id
unique ID to identify the chapter
Definition: avformat.h:1283
enum AVStreamParseType need_parsing
Definition: avformat.h:1063
int id
Format-specific stream ID.
Definition: avformat.h:883
int avformat_match_stream_specifier(AVFormatContext *s, AVStream *st, const char *spec)
Check if the stream st contained in s is matched by the stream specifier spec.
Definition: utils.c:4712
int duration_count
Definition: avformat.h:1012
int nb_side_data
The number of elements in the AVStream.side_data array.
Definition: avformat.h:987
AVDurationEstimationMethod
The duration of a video can be estimated through various ways, and this enum can be used to know how ...
Definition: avformat.h:1303
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4131
int pmt_pid
Definition: avformat.h:1261
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1393
int av_codec_get_tag2(const struct AVCodecTag *const *tags, enum AVCodecID id, unsigned int *tag)
Get the codec tag for the given codec id.
static AVFrame * frame
AVFormatContext * avformat_alloc_context(void)
Allocate an AVFormatContext.
Definition: options.c:132
int inject_global_side_data
Internal data to inject global side data.
Definition: avformat.h:1195
void av_pkt_dump_log2(void *avcl, int level, const AVPacket *pkt, int dump_payload, const AVStream *st)
Send a nice dump of a packet to the log.
Definition: dump.c:112
const char * avformat_configuration(void)
Return the libavformat build-time configuration.
Definition: utils.c:69
#define MAX_REORDER_DELAY
Definition: avformat.h:1071
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:685
int64_t last_duration
Definition: avformat.h:1025
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1436
AVProgram * av_new_program(AVFormatContext *s, int id)
Definition: utils.c:4227
char * protocol_whitelist
',' separated list of allowed protocols.
Definition: avformat.h:1861
int(* read_header)(struct AVFormatContext *)
Read the format header and initialize the AVFormatContext structure.
Definition: avformat.h:725
int64_t max_interleave_delta
Maximum buffering duration for interleaving.
Definition: avformat.h:1601
uint32_t tag
Definition: movenc.c:1376
int avformat_network_init(void)
Do global initialization of network components.
Definition: utils.c:4603
const struct AVCodecTag * avformat_get_riff_audio_tags(void)
Definition: riff.c:538
int fps_probe_size
The number of frames used for determining the framerate in avformat_find_stream_info().
Definition: avformat.h:1559
int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size)
Generate an SDP for an RTP session.
Definition: sdp.c:827
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:260
int av_match_ext(const char *filename, const char *extensions)
Return a positive value if the given filename has one of the given extensions, 0 otherwise.
Definition: format.c:85
const AVClass * avformat_get_class(void)
Get the AVClass for AVFormatContext.
Definition: options.c:155
ptrdiff_t size
Definition: opengl_enc.c:101
int av_probe_input_buffer2(AVIOContext *pb, AVInputFormat **fmt, const char *url, void *logctx, unsigned int offset, unsigned int max_probe_size)
Probe a bytestream to determine the input format.
Definition: format.c:266
enum AVDiscard discard
selects which program to discard and which to feed to the caller
Definition: avformat.h:1255
const OptionDef options[]
Definition: ffserver.c:3969
unsigned int * stream_index
Definition: avformat.h:1256
AVCodec * av_format_get_audio_codec(const AVFormatContext *s)
enum AVCodecID video_codec_id
Forced video codec_id.
Definition: avformat.h:1485
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:810
int64_t rfps_duration_sum
Definition: avformat.h:1013
Duration estimated from bitrate (less accurate)
Definition: avformat.h:1306
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:270
unsigned int correct_ts_overflow
Correct single timestamp overflows.
Definition: avformat.h:1700
struct AVOutputFormat * oformat
The output container format.
Definition: avformat.h:1344
int64_t start_time
Definition: avformat.h:1271
const struct AVCodecTag * avformat_get_mov_video_tags(void)
Definition: isom.c:622
int avformat_alloc_output_context2(AVFormatContext **ctx, AVOutputFormat *oformat, const char *format_name, const char *filename)
Allocate an AVFormatContext for an output format.
Definition: mux.c:148
void av_dump_format(AVFormatContext *ic, int index, const char *url, int is_output)
Print detailed information about the input or output format, such as duration, bitrate, streams, container, programs, metadata, side data, codec and time base.
Definition: dump.c:511
Callback for checking whether to abort blocking functions.
Definition: avio.h:50
int av_find_best_stream(AVFormatContext *ic, enum AVMediaType type, int wanted_stream_nb, int related_stream, AVCodec **decoder_ret, int flags)
Find the "best" stream in the file.
Definition: utils.c:3872
int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt, const char *url, void *logctx, unsigned int offset, unsigned int max_probe_size)
Like av_probe_input_buffer2() but returns 0 on success.
Definition: format.c:364
int(* write_uncoded_frame)(struct AVFormatContext *, int stream_index, AVFrame **frame, unsigned flags)
Write an uncoded AVFrame.
Definition: avformat.h:605
AVProgram * av_find_program_from_stream(AVFormatContext *ic, AVProgram *last, int s)
Find the programs which belong to a given stream.
Definition: utils.c:3855
int max_ts_probe
Maximum number of packets to read while waiting for the first timestamp.
Definition: avformat.h:1621
int format_probesize
number of bytes to read maximally to identify format.
Definition: avformat.h:1730
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:189
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1539
int nb_decoded_frames
Number of internally decoded frames, used internally in libavformat, do not access its lifetime diffe...
Definition: avformat.h:1149
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2008
const AVIOInterruptCB int_cb
Definition: ffmpeg.c:457
int(* read_probe)(AVProbeData *)
Tell if a given file has a chance of being parsed as this format.
Definition: avformat.h:718
void av_hex_dump(FILE *f, const uint8_t *buf, int size)
Send a nice hexadecimal dump of a buffer to the specified file stream.
Definition: dump.c:73
int64_t pts_wrap_reference
reference dts for wrap detection
Definition: avformat.h:1274
const char * long_name
Descriptive name for the format, meant to be more human-readable than name.
Definition: avformat.h:528
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:817
void av_format_set_data_codec(AVFormatContext *s, AVCodec *c)
int(* query_codec)(enum AVCodecID id, int std_compliance)
Test if the given codec can be stored in this container.
Definition: avformat.h:587
AVCodec * av_format_get_subtitle_codec(const AVFormatContext *s)
int(* write_header)(struct AVFormatContext *)
Definition: avformat.h:565
const char * r
Definition: vf_curves.c:111
struct AVCodecParserContext * av_stream_get_parser(const AVStream *s)
Definition: utils.c:130
unsigned int nb_programs
Definition: avformat.h:1478
int last_IP_duration
Definition: avformat.h:1050
int av_read_play(AVFormatContext *s)
Start playing a network-based stream (e.g.
Definition: utils.c:3936
AVChapter ** chapters
Definition: avformat.h:1529
int skip_samples
Number of samples to skip at the start of the frame decoded from the next packet. ...
Definition: avformat.h:1119
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:954
New fields can be added to the end with minor version bumps.
Definition: avformat.h:1252
AVInputFormat * av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max)
Guess the file format.
Definition: format.c:249
int min_distance
Minimum distance between this and the previous keyframe, used to avoid unneeded searching.
Definition: avformat.h:826
int program_num
Definition: avformat.h:1260
AVCodec * audio_codec
Forced audio codec.
Definition: avformat.h:1776
void * opaque
User data.
Definition: avformat.h:1805
Only parse headers, do not repack.
Definition: avformat.h:807
char * format_whitelist
',' separated list of allowed demuxers.
Definition: avformat.h:1746
int avformat_query_codec(const AVOutputFormat *ofmt, enum AVCodecID codec_id, int std_compliance)
Test if the given container can store a codec.
Definition: utils.c:4586
static float distance(float x, float y, int band)
const char * mime_type
mime_type, when known.
Definition: avformat.h:463
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:462
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:461
void av_format_inject_global_side_data(AVFormatContext *s)
This function will cause global side data to be injected in the next packet of each stream as well as...
Definition: utils.c:135
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1381
void av_stream_set_recommended_encoder_configuration(AVStream *s, char *configuration)
int64_t fps_first_dts
Those are used for average framerate estimation.
Definition: avformat.h:1030
int av_read_pause(AVFormatContext *s)
Pause a network-based stream (e.g.
Definition: utils.c:3945
AVInputFormat * av_find_input_format(const char *short_name)
Find AVInputFormat based on the short name of the input format.
Definition: format.c:164
static void callback(void *priv_data, int index, uint8_t *buf, int buf_size, int64_t time, enum dshowDeviceType devtype)
Definition: dshow.c:161
char filename[1024]
input or output filename
Definition: avformat.h:1401
int update_initial_durations_done
Internal data to prevent doing update_initial_durations() twice.
Definition: avformat.h:1177
av_warn_unused_result int avformat_write_header(AVFormatContext *s, AVDictionary **options)
Allocate the stream private data and write the stream header to an output media file.
Definition: mux.c:496
void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx)
enum AVCodecID audio_codec_id
Forced audio codec_id.
Definition: avformat.h:1491
enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name, const char *filename, const char *mime_type, enum AVMediaType type)
Guess the codec ID based upon muxer and filename.
Definition: format.c:133
typedef void(APIENTRY *FF_PFNGLACTIVETEXTUREPROC)(GLenum texture)
int av_find_default_stream_index(AVFormatContext *s)
Definition: utils.c:1750
void av_format_set_opaque(AVFormatContext *s, void *opaque)
const char * name
Definition: avformat.h:522
Duration estimated from a stream with a known duration.
Definition: avformat.h:1305
AVFormatContext * ctx
Definition: movenc.c:48
uint8_t dts_ordered
Definition: avformat.h:1189
int avoid_negative_ts
Avoid negative timestamps during muxing.
Definition: avformat.h:1630
int(* control_message)(struct AVFormatContext *s, int type, void *data, size_t data_size)
Allows sending messages from application to device.
Definition: avformat.h:594
AVDictionary * metadata
Definition: avformat.h:945
uint8_t * av_stream_new_side_data(AVStream *stream, enum AVPacketSideDataType type, int size)
Allocate new information from stream.
Definition: utils.c:5020
AVOutputFormat * av_guess_format(const char *short_name, const char *filename, const char *mime_type)
Return the output format in the list of registered output formats which best matches the provided par...
Definition: format.c:98
int probe_score
format probing score.
Definition: avformat.h:1723
void av_register_input_format(AVInputFormat *format)
Definition: format.c:61
void av_format_set_audio_codec(AVFormatContext *s, AVCodec *c)
Libavformat version macros.
int64_t skip_initial_bytes
Skip initial bytes when opening stream.
Definition: avformat.h:1693
void(* get_output_timestamp)(struct AVFormatContext *s, int stream, int64_t *dts, int64_t *wall)
Definition: avformat.h:589
int(* read_pause)(struct AVFormatContext *)
Pause playing - only meaningful if using a network-based format (RTSP).
Definition: avformat.h:772
AVOutputFormat * av_oformat_next(const AVOutputFormat *f)
If f is NULL, returns the first registered output format, if f is non-NULL, returns the next register...
Definition: format.c:53
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:550
void * av_format_get_opaque(const AVFormatContext *s)
int64_t max_analyze_duration
Maximum duration (in AV_TIME_BASE units) of the data read from input in avformat_find_stream_info().
Definition: avformat.h:1473
int(* get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list)
Returns device list with it properties.
Definition: avformat.h:611
int av_get_frame_filename(char *buf, int buf_size, const char *path, int number)
Return in 'buf' the path with 'd' replaced by a number.
Definition: utils.c:4318
uint8_t pts_reorder_error_count[MAX_REORDER_DELAY+1]
Definition: avformat.h:1183
int ts_id
Transport stream id.
Definition: avformat.h:1639
const char * long_name
Descriptive name for the format, meant to be more human-readable than name.
Definition: avformat.h:667
int metadata_header_padding
Number of bytes to be written as padding in a metadata header.
Definition: avformat.h:1799
int av_format_get_probe_score(const AVFormatContext *s)
Definition: utils.c:189
Stream structure.
Definition: avformat.h:876
int(* create_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps)
Initialize device capabilities submodule.
Definition: avformat.h:616
int64_t end
chapter start/end time in time_base units
Definition: avformat.h:1285
int avformat_queue_attached_pictures(AVFormatContext *s)
Definition: utils.c:420
void av_register_output_format(AVOutputFormat *format)
Definition: format.c:73
int avformat_network_deinit(void)
Undo the initialization done by avformat_network_init.
Definition: utils.c:4616
uint8_t dts_misordered
Definition: avformat.h:1190
int64_t pts_reorder_error[MAX_REORDER_DELAY+1]
Internal data to generate dts from pts.
Definition: avformat.h:1182
int64_t end_time
Definition: avformat.h:1272
Libavcodec external API header.
struct AVOutputFormat * next
Definition: avformat.h:559
int(* read_seek)(struct AVFormatContext *, int stream_index, int64_t timestamp, int flags)
Seek to a given timestamp relative to the frames in stream component stream_index.
Definition: avformat.h:752
int debug
Flags to enable debugging.
Definition: avformat.h:1582
AVIOContext * pb
I/O context.
Definition: avformat.h:1367
const struct AVCodecTag *const * codec_tag
List of supported codec_id-codec_tag pairs, ordered by "better choice first".
Definition: avformat.h:547
main external API structure.
Definition: avcodec.h:1657
int io_repositioned
IO repositioned flag.
Definition: avformat.h:1760
int av_filename_number_test(const char *filename)
Check whether filename actually is a numbered sequence generator.
Definition: utils.c:277
void av_format_set_video_codec(AVFormatContext *s, AVCodec *c)
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) returnNULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt)>2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);returnNULL;}returnac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_log(ac->avr, AV_LOG_TRACE,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> in
int(* read_packet)(struct AVFormatContext *, AVPacket *pkt)
Read one packet and put it in 'pkt'.
Definition: avformat.h:736
int pts_wrap_behavior
behavior on wrap detection
Definition: avformat.h:1275
void * buf
Definition: avisynth_c.h:553
double(* duration_error)[2][MAX_STD_TIMEBASES]
Definition: avformat.h:1014
GLint GLenum type
Definition: opengl_enc.c:105
int nb_index_entries
Definition: avformat.h:1076
static const char * format
Definition: movenc.c:47
Describe the class of an AVClass context structure.
Definition: log.h:67
int index
Definition: gxfenc.c:89
int(* create_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps)
Initialize device capabilities submodule.
Definition: avformat.h:792
enum AVCodecID subtitle_codec
default subtitle codec
Definition: avformat.h:534
rational number numerator/denominator
Definition: rational.h:43
int64_t last_dts
Definition: avformat.h:1010
AVRational display_aspect_ratio
display aspect ratio (0 if unknown)
Definition: avformat.h:1209
AVRational av_stream_get_r_frame_rate(const AVStream *s)
const AVClass * av_class
A class for logging and AVOptions.
Definition: avformat.h:1330
AVMediaType
Definition: avutil.h:191
int(* interleave_packet)(struct AVFormatContext *, AVPacket *out, AVPacket *in, int flush)
Currently only used to set pixel format if not YUV420P.
Definition: avformat.h:578
int64_t fps_last_dts
Definition: avformat.h:1032
int found_decoder
0 -> decoder has not been searched for yet.
Definition: avformat.h:1023
void avformat_free_context(AVFormatContext *s)
Free an AVFormatContext and all its streams.
Definition: utils.c:4067
This structure contains the data a format has to probe a file.
Definition: avformat.h:459
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: utils.c:1640
List of devices.
Definition: avdevice.h:459
int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Seek to timestamp ts.
Definition: utils.c:2389
int seek2any
Force seeking to any (also non key) frames.
Definition: avformat.h:1707
full parsing and repack of the first frame only, only implemented for H.264 currently ...
Definition: avformat.h:809
int raw_codec_id
Raw demuxers store their codec ID here.
Definition: avformat.h:706
AVDictionary * metadata
Definition: avformat.h:1258
int64_t codec_info_duration
Definition: avformat.h:1015
static int64_t pts
Global timestamp for the audio frames.
int fps_first_dts_idx
Definition: avformat.h:1031
static int flags
Definition: cpu.c:47
av_format_control_message av_format_get_control_message_cb(const AVFormatContext *s)
int64_t start_time
Position of the first frame of the component, in AV_TIME_BASE fractional seconds. ...
Definition: avformat.h:1410
const char * mime_type
Comma-separated list of mime types.
Definition: avformat.h:692
uint8_t level
Definition: svq3.c:193
#define attribute_deprecated
Definition: attributes.h:94
Duration accurately estimated from PTSes.
Definition: avformat.h:1304
#define av_warn_unused_result
Definition: attributes.h:56
int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Seek to the keyframe at timestamp.
Definition: utils.c:2366
int64_t start
Definition: avformat.h:1285
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:930
int64_t interleaver_chunk_duration
Definition: avformat.h:1100
const char * extensions
If extensions are defined, then no probe is done.
Definition: avformat.h:681
const uint8_t * key
Definition: avformat.h:1475
full parsing and repack
Definition: avformat.h:806
int av_interleaved_write_uncoded_frame(AVFormatContext *s, int stream_index, AVFrame *frame)
Write an uncoded frame to an output media file.
Definition: mux.c:1329
struct AVPacketList * next
Definition: avformat.h:1934
int pts_wrap_behavior
Options for behavior, when a wrap is detected.
Definition: avformat.h:1172
int(* read_play)(struct AVFormatContext *)
Start/resume playing - only meaningful if using a network-based format (RTSP).
Definition: avformat.h:766
enum AVCodecID data_codec
default data codec
Definition: avformat.h:622
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
Definition: utils.c:3277
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:923
AVCodec * video_codec
Forced video codec.
Definition: avformat.h:1768
static double c[64]
int max_chunk_size
Max chunk size in bytes Note, not all formats support this and unpredictable things may happen if it ...
Definition: avformat.h:1663
int error_recognition
Error recognition; higher values will detect more errors but may misdetect some more or less valid pa...
Definition: avformat.h:1566
int disposition
AV_DISPOSITION_* bit field.
Definition: avformat.h:934
AVStreamParseType
Definition: avformat.h:804
int(* av_format_control_message)(struct AVFormatContext *s, int type, void *data, size_t data_size)
Callback used by devices to communicate with application.
Definition: avformat.h:1293
int pts_wrap_bits
number of bits in pts (used for wrapping control)
Definition: avformat.h:1037
AVRational time_base
time base in which the start/end timestamps are specified
Definition: avformat.h:1284
av_format_control_message control_message_cb
Callback used by devices to communicate with application.
Definition: avformat.h:1810
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:932
struct AVInputFormat * iformat
The input container format.
Definition: avformat.h:1337
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: utils.c:4103
int av_write_uncoded_frame(AVFormatContext *s, int stream_index, AVFrame *frame)
Write an uncoded frame to an output media file.
Definition: mux.c:1323
int64_t codec_info_duration_fields
Definition: avformat.h:1016
unsigned int index_entries_allocated_size
Definition: avformat.h:1077
int64_t mux_ts_offset
Timestamp offset added to timestamps before muxing NOT PART OF PUBLIC API.
Definition: avformat.h:1155
int skip_to_keyframe
Indicates that everything up to the next keyframe should be discarded.
Definition: avformat.h:1114
enum AVCodecID data_codec_id
Forced Data codec_id.
Definition: avformat.h:1832
AVCodec * subtitle_codec
Forced subtitle codec.
Definition: avformat.h:1784
int(* AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options)
Definition: avformat.h:1296
AVCodec * data_codec
Forced data codec.
Definition: avformat.h:1792
enum AVCodecID audio_codec
default audio codec
Definition: avformat.h:532
char * codec_whitelist
',' separated list of allowed decoders.
Definition: avformat.h:1738
int(* get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list)
Returns device list with it properties.
Definition: avformat.h:786
int max_chunk_duration
Max chunk time in microseconds.
Definition: avformat.h:1655
struct AVCodecParserContext * parser
Definition: avformat.h:1064
void * priv_data
Format private data.
Definition: avformat.h:1353
int pcr_pid
Definition: avformat.h:1262
int codec_info_nb_frames
Number of frames that have been demuxed during av_find_stream_info()
Definition: avformat.h:1060
void av_format_set_control_message_cb(AVFormatContext *s, av_format_control_message callback)
int avformat_open_input(AVFormatContext **ps, const char *url, AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: utils.c:471
AVDiscard
Definition: avcodec.h:775
int av_format_get_metadata_header_padding(const AVFormatContext *s)
char * av_stream_get_recommended_encoder_configuration(const AVStream *s)
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
Definition: mux.c:1200
char * protocol_blacklist
',' separated list of disallowed protocols.
Definition: avformat.h:1896
int64_t duration
Duration of the stream, in AV_TIME_BASE fractional seconds.
Definition: avformat.h:1420
int avformat_flush(AVFormatContext *s)
Discard all internally buffered data.
Definition: utils.c:2445
void av_format_set_metadata_header_padding(AVFormatContext *s, int c)
FILE * out
Definition: movenc.c:54
int64_t last_IP_pts
Definition: avformat.h:1049
int(* read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Seek to timestamp ts.
Definition: avformat.h:780
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:660
AVCodecParameters * codecpar
Definition: avformat.h:1228
void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size)
Send a nice hexadecimal dump of a buffer to the log.
Definition: dump.c:78
int fps_last_dts_idx
Definition: avformat.h:1033
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:913
struct AVInputFormat * next
Definition: avformat.h:701
AVCodec * av_format_get_data_codec(const AVFormatContext *s)
#define MKTAG(a, b, c, d)
Definition: common.h:342
unsigned int av_codec_get_tag(const struct AVCodecTag *const *tags, enum AVCodecID id)
Get the codec tag for the given codec id id.
const char * extensions
comma-separated filename extensions
Definition: avformat.h:530
enum AVDiscard discard
Selects which packets can be discarded at will and do not need to be demuxed.
Definition: avformat.h:936
AVRational r_frame_rate
Real base framerate of the stream.
Definition: avformat.h:1090
int(* io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags, AVDictionary **options)
Definition: avformat.h:1883
AVInputFormat * av_probe_input_format(AVProbeData *pd, int is_opened)
Guess the file format.
Definition: format.c:260
const char * mime_type
Definition: avformat.h:529
int request_probe
stream probing state -1 -> probing finished 0 -> no probing requested rest -> perform probing with re...
Definition: avformat.h:1109
Following API allows user to probe device capabilities (supported codecs, pixel formats, sample formats, resolutions, channel counts, etc).
Definition: avdevice.h:399
int use_wallclock_as_timestamps
forces the use of wallclock timestamps as pts/dts of packets This has undefined results in the presen...
Definition: avformat.h:1671
This structure stores compressed data.
Definition: avcodec.h:1565
void av_register_all(void)
Initialize libavformat and register all the muxers, demuxers and protocols.
Definition: allformats.c:44
int(* write_trailer)(struct AVFormatContext *)
Definition: avformat.h:574
void(* io_close)(struct AVFormatContext *s, AVIOContext *pb)
A callback for closing the streams opened with AVFormatContext.io_open().
Definition: avformat.h:1889
#define MAX_STD_TIMEBASES
Stream information used internally by av_find_stream_info()
Definition: avformat.h:1008
const struct AVCodecTag *const * codec_tag
Definition: avformat.h:683
int64_t av_stream_get_end_pts(const AVStream *st)
Returns the pts of the last muxed packet + its duration.
Definition: utils.c:122
AVPacket attached_pic
For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet will contain the attached pictu...
Definition: avformat.h:963
struct AVPacketList * last_in_packet_buffer
last packet in packet_buffer for this stream when muxing.
Definition: avformat.h:1069
AVInputFormat * av_iformat_next(const AVInputFormat *f)
If f is NULL, returns the first registered input format, if f is non-NULL, returns the next registere...
Definition: format.c:45
int64_t last_discard_sample
The sample after last sample that is intended to be discarded after first_discard_sample.
Definition: avformat.h:1143
AVProgram ** programs
Definition: avformat.h:1479