FFmpeg
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 libavformat
32  * I/O and Muxing/Demuxing Library
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).
40  * Unless you are absolutely sure you won't use libavformat's network
41  * capabilities, you should also call avformat_network_init().
42  *
43  * A supported input format is described by an AVInputFormat struct, conversely
44  * an output format is described by AVOutputFormat. You can iterate over all
45  * input/output formats using the av_demuxer_iterate / av_muxer_iterate() functions.
46  * The protocols layer is not part of the public API, so you can only get the names
47  * of supported protocols with the avio_enum_protocols() function.
48  *
49  * Main lavf structure used for both muxing and demuxing is AVFormatContext,
50  * which exports all information about the file being read or written. As with
51  * most Libavformat structures, its size is not part of public ABI, so it cannot be
52  * allocated on stack or directly with av_malloc(). To create an
53  * AVFormatContext, use avformat_alloc_context() (some functions, like
54  * avformat_open_input() might do that for you).
55  *
56  * Most importantly an AVFormatContext contains:
57  * @li the @ref AVFormatContext.iformat "input" or @ref AVFormatContext.oformat
58  * "output" format. It is either autodetected or set by user for input;
59  * always set by user for output.
60  * @li an @ref AVFormatContext.streams "array" of AVStreams, which describe all
61  * elementary streams stored in the file. AVStreams are typically referred to
62  * using their index in this array.
63  * @li an @ref AVFormatContext.pb "I/O context". It is either opened by lavf or
64  * set by user for input, always set by user for output (unless you are dealing
65  * with an AVFMT_NOFILE format).
66  *
67  * @section lavf_options Passing options to (de)muxers
68  * It is possible to configure lavf muxers and demuxers using the @ref avoptions
69  * mechanism. Generic (format-independent) libavformat options are provided by
70  * AVFormatContext, they can be examined from a user program by calling
71  * av_opt_next() / av_opt_find() on an allocated AVFormatContext (or its AVClass
72  * from avformat_get_class()). Private (format-specific) options are provided by
73  * AVFormatContext.priv_data if and only if AVInputFormat.priv_class /
74  * AVOutputFormat.priv_class of the corresponding format struct is non-NULL.
75  * Further options may be provided by the @ref AVFormatContext.pb "I/O context",
76  * if its AVClass is non-NULL, and the protocols layer. See the discussion on
77  * nesting in @ref avoptions documentation to learn how to access those.
78  *
79  * @section urls
80  * URL strings in libavformat are made of a scheme/protocol, a ':', and a
81  * scheme specific string. URLs without a scheme and ':' used for local files
82  * are supported but deprecated. "file:" should be used for local files.
83  *
84  * It is important that the scheme string is not taken from untrusted
85  * sources without checks.
86  *
87  * Note that some schemes/protocols are quite powerful, allowing access to
88  * both local and remote files, parts of them, concatenations of them, local
89  * audio and video devices and so on.
90  *
91  * @{
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  * A packet returned by av_read_frame() is always reference-counted,
174  * i.e. AVPacket.buf is set and the user may keep it indefinitely.
175  * The packet must be freed with av_packet_unref() when it is no
176  * longer needed.
177  *
178  * @section lavf_decoding_seek Seeking
179  * @}
180  *
181  * @defgroup lavf_encoding Muxing
182  * @{
183  * Muxers take encoded data in the form of @ref AVPacket "AVPackets" and write
184  * it into files or other output bytestreams in the specified container format.
185  *
186  * The main API functions for muxing are avformat_write_header() for writing the
187  * file header, av_write_frame() / av_interleaved_write_frame() for writing the
188  * packets and av_write_trailer() for finalizing the file.
189  *
190  * At the beginning of the muxing process, the caller must first call
191  * avformat_alloc_context() to create a muxing context. The caller then sets up
192  * the muxer by filling the various fields in this context:
193  *
194  * - The @ref AVFormatContext.oformat "oformat" field must be set to select the
195  * muxer that will be used.
196  * - Unless the format is of the AVFMT_NOFILE type, the @ref AVFormatContext.pb
197  * "pb" field must be set to an opened IO context, either returned from
198  * avio_open2() or a custom one.
199  * - Unless the format is of the AVFMT_NOSTREAMS type, at least one stream must
200  * be created with the avformat_new_stream() function. The caller should fill
201  * the @ref AVStream.codecpar "stream codec parameters" information, such as the
202  * codec @ref AVCodecParameters.codec_type "type", @ref AVCodecParameters.codec_id
203  * "id" and other parameters (e.g. width / height, the pixel or sample format,
204  * etc.) as known. The @ref AVStream.time_base "stream timebase" should
205  * be set to the timebase that the caller desires to use for this stream (note
206  * that the timebase actually used by the muxer can be different, as will be
207  * described later).
208  * - It is advised to manually initialize only the relevant fields in
209  * AVCodecParameters, rather than using @ref avcodec_parameters_copy() during
210  * remuxing: there is no guarantee that the codec context values remain valid
211  * for both input and output format contexts.
212  * - The caller may fill in additional information, such as @ref
213  * AVFormatContext.metadata "global" or @ref AVStream.metadata "per-stream"
214  * metadata, @ref AVFormatContext.chapters "chapters", @ref
215  * AVFormatContext.programs "programs", etc. as described in the
216  * AVFormatContext documentation. Whether such information will actually be
217  * stored in the output depends on what the container format and the muxer
218  * support.
219  *
220  * When the muxing context is fully set up, the caller must call
221  * avformat_write_header() to initialize the muxer internals and write the file
222  * header. Whether anything actually is written to the IO context at this step
223  * depends on the muxer, but this function must always be called. Any muxer
224  * private options must be passed in the options parameter to this function.
225  *
226  * The data is then sent to the muxer by repeatedly calling av_write_frame() or
227  * av_interleaved_write_frame() (consult those functions' documentation for
228  * discussion on the difference between them; only one of them may be used with
229  * a single muxing context, they should not be mixed). Do note that the timing
230  * information on the packets sent to the muxer must be in the corresponding
231  * AVStream's timebase. That timebase is set by the muxer (in the
232  * avformat_write_header() step) and may be different from the timebase
233  * requested by the caller.
234  *
235  * Once all the data has been written, the caller must call av_write_trailer()
236  * to flush any buffered packets and finalize the output file, then close the IO
237  * context (if any) and finally free the muxing context with
238  * avformat_free_context().
239  * @}
240  *
241  * @defgroup lavf_io I/O Read/Write
242  * @{
243  * @section lavf_io_dirlist Directory listing
244  * The directory listing API makes it possible to list files on remote servers.
245  *
246  * Some of possible use cases:
247  * - an "open file" dialog to choose files from a remote location,
248  * - a recursive media finder providing a player with an ability to play all
249  * files from a given directory.
250  *
251  * @subsection lavf_io_dirlist_open Opening a directory
252  * At first, a directory needs to be opened by calling avio_open_dir()
253  * supplied with a URL and, optionally, ::AVDictionary containing
254  * protocol-specific parameters. The function returns zero or positive
255  * integer and allocates AVIODirContext on success.
256  *
257  * @code
258  * AVIODirContext *ctx = NULL;
259  * if (avio_open_dir(&ctx, "smb://example.com/some_dir", NULL) < 0) {
260  * fprintf(stderr, "Cannot open directory.\n");
261  * abort();
262  * }
263  * @endcode
264  *
265  * This code tries to open a sample directory using smb protocol without
266  * any additional parameters.
267  *
268  * @subsection lavf_io_dirlist_read Reading entries
269  * Each directory's entry (i.e. file, another directory, anything else
270  * within ::AVIODirEntryType) is represented by AVIODirEntry.
271  * Reading consecutive entries from an opened AVIODirContext is done by
272  * repeatedly calling avio_read_dir() on it. Each call returns zero or
273  * positive integer if successful. Reading can be stopped right after the
274  * NULL entry has been read -- it means there are no entries left to be
275  * read. The following code reads all entries from a directory associated
276  * with ctx and prints their names to standard output.
277  * @code
278  * AVIODirEntry *entry = NULL;
279  * for (;;) {
280  * if (avio_read_dir(ctx, &entry) < 0) {
281  * fprintf(stderr, "Cannot list directory.\n");
282  * abort();
283  * }
284  * if (!entry)
285  * break;
286  * printf("%s\n", entry->name);
287  * avio_free_directory_entry(&entry);
288  * }
289  * @endcode
290  * @}
291  *
292  * @defgroup lavf_codec Demuxers
293  * @{
294  * @defgroup lavf_codec_native Native Demuxers
295  * @{
296  * @}
297  * @defgroup lavf_codec_wrappers External library wrappers
298  * @{
299  * @}
300  * @}
301  * @defgroup lavf_protos I/O Protocols
302  * @{
303  * @}
304  * @defgroup lavf_internal Internal
305  * @{
306  * @}
307  * @}
308  */
309 
310 #include <stdio.h> /* FILE */
311 
312 #include "libavcodec/codec_par.h"
313 #include "libavcodec/defs.h"
314 #include "libavcodec/packet.h"
315 
316 #include "libavutil/dict.h"
317 #include "libavutil/log.h"
318 
319 #include "avio.h"
321 #ifndef HAVE_AV_CONFIG_H
322 /* When included as part of the ffmpeg build, only include the major version
323  * to avoid unnecessary rebuilds. When included externally, keep including
324  * the full version information. */
325 #include "libavformat/version.h"
326 
327 #include "libavutil/frame.h"
328 #include "libavcodec/codec.h"
329 #endif
330 
331 struct AVFormatContext;
332 struct AVFrame;
333 struct AVDeviceInfoList;
334 
335 /**
336  * @defgroup metadata_api Public Metadata API
337  * @{
338  * @ingroup libavf
339  * The metadata API allows libavformat to export metadata tags to a client
340  * application when demuxing. Conversely it allows a client application to
341  * set metadata when muxing.
342  *
343  * Metadata is exported or set as pairs of key/value strings in the 'metadata'
344  * fields of the AVFormatContext, AVStream, AVChapter and AVProgram structs
345  * using the @ref lavu_dict "AVDictionary" API. Like all strings in FFmpeg,
346  * metadata is assumed to be UTF-8 encoded Unicode. Note that metadata
347  * exported by demuxers isn't checked to be valid UTF-8 in most cases.
348  *
349  * Important concepts to keep in mind:
350  * - Keys are unique; there can never be 2 tags with the same key. This is
351  * also meant semantically, i.e., a demuxer should not knowingly produce
352  * several keys that are literally different but semantically identical.
353  * E.g., key=Author5, key=Author6. In this example, all authors must be
354  * placed in the same tag.
355  * - Metadata is flat, not hierarchical; there are no subtags. If you
356  * want to store, e.g., the email address of the child of producer Alice
357  * and actor Bob, that could have key=alice_and_bobs_childs_email_address.
358  * - Several modifiers can be applied to the tag name. This is done by
359  * appending a dash character ('-') and the modifier name in the order
360  * they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng.
361  * - language -- a tag whose value is localized for a particular language
362  * is appended with the ISO 639-2/B 3-letter language code.
363  * For example: Author-ger=Michael, Author-eng=Mike
364  * The original/default language is in the unqualified "Author" tag.
365  * A demuxer should set a default if it sets any translated tag.
366  * - sorting -- a modified version of a tag that should be used for
367  * sorting will have '-sort' appended. E.g. artist="The Beatles",
368  * artist-sort="Beatles, The".
369  * - Some protocols and demuxers support metadata updates. After a successful
370  * call to av_read_frame(), AVFormatContext.event_flags or AVStream.event_flags
371  * will be updated to indicate if metadata changed. In order to detect metadata
372  * changes on a stream, you need to loop through all streams in the AVFormatContext
373  * and check their individual event_flags.
374  *
375  * - Demuxers attempt to export metadata in a generic format, however tags
376  * with no generic equivalents are left as they are stored in the container.
377  * Follows a list of generic tag names:
378  *
379  @verbatim
380  album -- name of the set this work belongs to
381  album_artist -- main creator of the set/album, if different from artist.
382  e.g. "Various Artists" for compilation albums.
383  artist -- main creator of the work
384  comment -- any additional description of the file.
385  composer -- who composed the work, if different from artist.
386  copyright -- name of copyright holder.
387  creation_time-- date when the file was created, preferably in ISO 8601.
388  date -- date when the work was created, preferably in ISO 8601.
389  disc -- number of a subset, e.g. disc in a multi-disc collection.
390  encoder -- name/settings of the software/hardware that produced the file.
391  encoded_by -- person/group who created the file.
392  filename -- original name of the file.
393  genre -- <self-evident>.
394  language -- main language in which the work is performed, preferably
395  in ISO 639-2 format. Multiple languages can be specified by
396  separating them with commas.
397  performer -- artist who performed the work, if different from artist.
398  E.g for "Also sprach Zarathustra", artist would be "Richard
399  Strauss" and performer "London Philharmonic Orchestra".
400  publisher -- name of the label/publisher.
401  service_name -- name of the service in broadcasting (channel name).
402  service_provider -- name of the service provider in broadcasting.
403  title -- name of the work.
404  track -- number of this work in the set, can be in form current/total.
405  variant_bitrate -- the total bitrate of the bitrate variant that the current stream is part of
406  @endverbatim
407  *
408  * Look in the examples section for an application example how to use the Metadata API.
409  *
410  * @}
411  */
412 
413 /* packet functions */
414 
415 
416 /**
417  * Allocate and read the payload of a packet and initialize its
418  * fields with default values.
419  *
420  * @param s associated IO context
421  * @param pkt packet
422  * @param size desired payload size
423  * @return >0 (read size) if OK, AVERROR_xxx otherwise
424  */
426 
427 
428 /**
429  * Read data and append it to the current content of the AVPacket.
430  * If pkt->size is 0 this is identical to av_get_packet.
431  * Note that this uses av_grow_packet and thus involves a realloc
432  * which is inefficient. Thus this function should only be used
433  * when there is no reasonable way to know (an upper bound of)
434  * the final size.
435  *
436  * @param s associated IO context
437  * @param pkt packet
438  * @param size amount of data to read
439  * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data
440  * will not be lost even if an error occurs.
441  */
443 
444 /*************************************************/
445 /* input/output formats */
446 
447 struct AVCodecTag;
448 
449 /**
450  * This structure contains the data a format has to probe a file.
451  */
452 typedef struct AVProbeData {
453  const char *filename;
454  unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
455  int buf_size; /**< Size of buf except extra allocated bytes */
456  const char *mime_type; /**< mime_type, when known. */
457 } AVProbeData;
458 
459 #define AVPROBE_SCORE_RETRY (AVPROBE_SCORE_MAX/4)
460 #define AVPROBE_SCORE_STREAM_RETRY (AVPROBE_SCORE_MAX/4-1)
461 
462 #define AVPROBE_SCORE_EXTENSION 50 ///< score for file extension
463 #define AVPROBE_SCORE_MIME 75 ///< score for file mime type
464 #define AVPROBE_SCORE_MAX 100 ///< maximum score
465 
466 #define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
467 
468 /// Demuxer will use avio_open, no opened file should be provided by the caller.
469 #define AVFMT_NOFILE 0x0001
470 #define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
471 /**
472  * The muxer/demuxer is experimental and should be used with caution.
473  *
474  * - demuxers: will not be selected automatically by probing, must be specified
475  * explicitly.
476  */
477 #define AVFMT_EXPERIMENTAL 0x0004
478 #define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
479 #define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
480 #define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
481 #define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
482 #define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */
483 #define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */
484 #define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */
485 #define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */
486 #define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fall back on binary search via read_timestamp */
487 #define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fall back on generic search */
488 #define AVFMT_NO_BYTE_SEEK 0x8000 /**< Format does not allow seeking by bytes */
489 #if FF_API_ALLOW_FLUSH
490 #define AVFMT_ALLOW_FLUSH 0x10000 /**< @deprecated: Just send a NULL packet if you want to flush a muxer. */
491 #endif
492 #define AVFMT_TS_NONSTRICT 0x20000 /**< Format does not require strictly
493  increasing timestamps, but they must
494  still be monotonic */
495 #define AVFMT_TS_NEGATIVE 0x40000 /**< Format allows muxing negative
496  timestamps. If not set the timestamp
497  will be shifted in av_write_frame and
498  av_interleaved_write_frame so they
499  start from 0.
500  The user or muxer can override this through
501  AVFormatContext.avoid_negative_ts
502  */
503 
504 #define AVFMT_SEEK_TO_PTS 0x4000000 /**< Seeking is based on PTS */
505 
506 /**
507  * @addtogroup lavf_encoding
508  * @{
509  */
510 typedef struct AVOutputFormat {
511  const char *name;
512  /**
513  * Descriptive name for the format, meant to be more human-readable
514  * than name. You should use the NULL_IF_CONFIG_SMALL() macro
515  * to define it.
516  */
517  const char *long_name;
518  const char *mime_type;
519  const char *extensions; /**< comma-separated filename extensions */
520  /* output support */
521  enum AVCodecID audio_codec; /**< default audio codec */
522  enum AVCodecID video_codec; /**< default video codec */
523  enum AVCodecID subtitle_codec; /**< default subtitle codec */
524  /**
525  * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER,
526  * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
527  * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS,
528  * AVFMT_TS_NONSTRICT, AVFMT_TS_NEGATIVE
529  */
530  int flags;
531 
532  /**
533  * List of supported codec_id-codec_tag pairs, ordered by "better
534  * choice first". The arrays are all terminated by AV_CODEC_ID_NONE.
535  */
536  const struct AVCodecTag * const *codec_tag;
537 
538 
539  const AVClass *priv_class; ///< AVClass for the private context
541 /**
542  * @}
543  */
544 
545 /**
546  * @addtogroup lavf_decoding
547  * @{
548  */
549 typedef struct AVInputFormat {
550  /**
551  * A comma separated list of short names for the format. New names
552  * may be appended with a minor bump.
553  */
554  const char *name;
555 
556  /**
557  * Descriptive name for the format, meant to be more human-readable
558  * than name. You should use the NULL_IF_CONFIG_SMALL() macro
559  * to define it.
560  */
561  const char *long_name;
562 
563  /**
564  * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
565  * AVFMT_NOTIMESTAMPS, AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
566  * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK, AVFMT_SEEK_TO_PTS.
567  */
568  int flags;
569 
570  /**
571  * If extensions are defined, then no probe is done. You should
572  * usually not use extension format guessing because it is not
573  * reliable enough
574  */
575  const char *extensions;
576 
577  const struct AVCodecTag * const *codec_tag;
578 
579  const AVClass *priv_class; ///< AVClass for the private context
580 
581  /**
582  * Comma-separated list of mime types.
583  * It is used check for matching mime types while probing.
584  * @see av_probe_input_format2
585  */
586  const char *mime_type;
587 
588  /*****************************************************************
589  * No fields below this line are part of the public API. They
590  * may not be used outside of libavformat and can be changed and
591  * removed at will.
592  * New public fields should be added right above.
593  *****************************************************************
594  */
595  /**
596  * Raw demuxers store their codec ID here.
597  */
599 
600  /**
601  * Size of private data so that it can be allocated in the wrapper.
602  */
604 
605  /**
606  * Internal flags. See FF_FMT_FLAG_* in internal.h.
607  */
609 
610  /**
611  * Tell if a given file has a chance of being parsed as this format.
612  * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
613  * big so you do not have to check for that unless you need more.
614  */
616 
617  /**
618  * Read the format header and initialize the AVFormatContext
619  * structure. Return 0 if OK. 'avformat_new_stream' should be
620  * called to create new streams.
621  */
623 
624  /**
625  * Read one packet and put it in 'pkt'. pts and flags are also
626  * set. 'avformat_new_stream' can be called only if the flag
627  * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
628  * background thread).
629  * @return 0 on success, < 0 on error.
630  * Upon returning an error, pkt must be unreferenced by the caller.
631  */
633 
634  /**
635  * Close the stream. The AVFormatContext and AVStreams are not
636  * freed by this function
637  */
639 
640  /**
641  * Seek to a given timestamp relative to the frames in
642  * stream component stream_index.
643  * @param stream_index Must not be -1.
644  * @param flags Selects which direction should be preferred if no exact
645  * match is available.
646  * @return >= 0 on success (but not necessarily the new offset)
647  */
649  int stream_index, int64_t timestamp, int flags);
650 
651  /**
652  * Get the next timestamp in stream[stream_index].time_base units.
653  * @return the timestamp or AV_NOPTS_VALUE if an error occurred
654  */
655  int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
656  int64_t *pos, int64_t pos_limit);
657 
658  /**
659  * Start/resume playing - only meaningful if using a network-based format
660  * (RTSP).
661  */
663 
664  /**
665  * Pause playing - only meaningful if using a network-based format
666  * (RTSP).
667  */
669 
670  /**
671  * Seek to timestamp ts.
672  * Seeking will be done so that the point from which all active streams
673  * can be presented successfully will be closest to ts and within min/max_ts.
674  * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
675  */
676  int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
677 
678  /**
679  * Returns device list with it properties.
680  * @see avdevice_list_devices() for more details.
681  */
682  int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
683 
684 } AVInputFormat;
685 /**
686  * @}
687  */
688 
691  AVSTREAM_PARSE_FULL, /**< full parsing and repack */
692  AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
693  AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
694  AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
695  AVSTREAM_PARSE_FULL_RAW, /**< full parsing and repack with timestamp and position generation by parser for raw
696  this assumes that each packet in the file contains no demuxer level headers and
697  just codec level data, otherwise position generation would fail */
698 };
699 
700 typedef struct AVIndexEntry {
701  int64_t pos;
702  int64_t timestamp; /**<
703  * Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are available
704  * when seeking to this entry. That means preferable PTS on keyframe based formats.
705  * But demuxers can choose to store a different timestamp, if it is more convenient for the implementation or nothing better
706  * is known
707  */
708 #define AVINDEX_KEYFRAME 0x0001
709 #define AVINDEX_DISCARD_FRAME 0x0002 /**
710  * Flag is used to indicate which frame should be discarded after decoding.
711  */
712  int flags:2;
713  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).
714  int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
715 } AVIndexEntry;
716 
717 /**
718  * The stream should be chosen by default among other streams of the same type,
719  * unless the user has explicitly specified otherwise.
720  */
721 #define AV_DISPOSITION_DEFAULT (1 << 0)
722 /**
723  * The stream is not in original language.
724  *
725  * @note AV_DISPOSITION_ORIGINAL is the inverse of this disposition. At most
726  * one of them should be set in properly tagged streams.
727  * @note This disposition may apply to any stream type, not just audio.
728  */
729 #define AV_DISPOSITION_DUB (1 << 1)
730 /**
731  * The stream is in original language.
732  *
733  * @see the notes for AV_DISPOSITION_DUB
734  */
735 #define AV_DISPOSITION_ORIGINAL (1 << 2)
736 /**
737  * The stream is a commentary track.
738  */
739 #define AV_DISPOSITION_COMMENT (1 << 3)
740 /**
741  * The stream contains song lyrics.
742  */
743 #define AV_DISPOSITION_LYRICS (1 << 4)
744 /**
745  * The stream contains karaoke audio.
746  */
747 #define AV_DISPOSITION_KARAOKE (1 << 5)
748 
749 /**
750  * Track should be used during playback by default.
751  * Useful for subtitle track that should be displayed
752  * even when user did not explicitly ask for subtitles.
753  */
754 #define AV_DISPOSITION_FORCED (1 << 6)
755 /**
756  * The stream is intended for hearing impaired audiences.
757  */
758 #define AV_DISPOSITION_HEARING_IMPAIRED (1 << 7)
759 /**
760  * The stream is intended for visually impaired audiences.
761  */
762 #define AV_DISPOSITION_VISUAL_IMPAIRED (1 << 8)
763 /**
764  * The audio stream contains music and sound effects without voice.
765  */
766 #define AV_DISPOSITION_CLEAN_EFFECTS (1 << 9)
767 /**
768  * The stream is stored in the file as an attached picture/"cover art" (e.g.
769  * APIC frame in ID3v2). The first (usually only) packet associated with it
770  * will be returned among the first few packets read from the file unless
771  * seeking takes place. It can also be accessed at any time in
772  * AVStream.attached_pic.
773  */
774 #define AV_DISPOSITION_ATTACHED_PIC (1 << 10)
775 /**
776  * The stream is sparse, and contains thumbnail images, often corresponding
777  * to chapter markers. Only ever used with AV_DISPOSITION_ATTACHED_PIC.
778  */
779 #define AV_DISPOSITION_TIMED_THUMBNAILS (1 << 11)
780 
781 /**
782  * The stream is intended to be mixed with a spatial audio track. For example,
783  * it could be used for narration or stereo music, and may remain unchanged by
784  * listener head rotation.
785  */
786 #define AV_DISPOSITION_NON_DIEGETIC (1 << 12)
787 
788 /**
789  * The subtitle stream contains captions, providing a transcription and possibly
790  * a translation of audio. Typically intended for hearing-impaired audiences.
791  */
792 #define AV_DISPOSITION_CAPTIONS (1 << 16)
793 /**
794  * The subtitle stream contains a textual description of the video content.
795  * Typically intended for visually-impaired audiences or for the cases where the
796  * video cannot be seen.
797  */
798 #define AV_DISPOSITION_DESCRIPTIONS (1 << 17)
799 /**
800  * The subtitle stream contains time-aligned metadata that is not intended to be
801  * directly presented to the user.
802  */
803 #define AV_DISPOSITION_METADATA (1 << 18)
804 /**
805  * The stream is intended to be mixed with another stream before presentation.
806  * Used for example to signal the stream contains an image part of a HEIF grid,
807  * or for mix_type=0 in mpegts.
808  */
809 #define AV_DISPOSITION_DEPENDENT (1 << 19)
810 /**
811  * The video stream contains still images.
812  */
813 #define AV_DISPOSITION_STILL_IMAGE (1 << 20)
814 
815 /**
816  * @return The AV_DISPOSITION_* flag corresponding to disp or a negative error
817  * code if disp does not correspond to a known stream disposition.
818  */
819 int av_disposition_from_string(const char *disp);
820 
821 /**
822  * @param disposition a combination of AV_DISPOSITION_* values
823  * @return The string description corresponding to the lowest set bit in
824  * disposition. NULL when the lowest set bit does not correspond
825  * to a known disposition or when disposition is 0.
826  */
827 const char *av_disposition_to_string(int disposition);
828 
829 /**
830  * Options for behavior on timestamp wrap detection.
831  */
832 #define AV_PTS_WRAP_IGNORE 0 ///< ignore the wrap
833 #define AV_PTS_WRAP_ADD_OFFSET 1 ///< add the format specific offset on wrap detection
834 #define AV_PTS_WRAP_SUB_OFFSET -1 ///< subtract the format specific offset on wrap detection
835 
836 /**
837  * Stream structure.
838  * New fields can be added to the end with minor version bumps.
839  * Removal, reordering and changes to existing fields require a major
840  * version bump.
841  * sizeof(AVStream) must not be used outside libav*.
842  */
843 typedef struct AVStream {
844  /**
845  * A class for @ref avoptions. Set on stream creation.
846  */
848 
849  int index; /**< stream index in AVFormatContext */
850  /**
851  * Format-specific stream ID.
852  * decoding: set by libavformat
853  * encoding: set by the user, replaced by libavformat if left unset
854  */
855  int id;
856 
857  /**
858  * Codec parameters associated with this stream. Allocated and freed by
859  * libavformat in avformat_new_stream() and avformat_free_context()
860  * respectively.
861  *
862  * - demuxing: filled by libavformat on stream creation or in
863  * avformat_find_stream_info()
864  * - muxing: filled by the caller before avformat_write_header()
865  */
867 
868  void *priv_data;
869 
870  /**
871  * This is the fundamental unit of time (in seconds) in terms
872  * of which frame timestamps are represented.
873  *
874  * decoding: set by libavformat
875  * encoding: May be set by the caller before avformat_write_header() to
876  * provide a hint to the muxer about the desired timebase. In
877  * avformat_write_header(), the muxer will overwrite this field
878  * with the timebase that will actually be used for the timestamps
879  * written into the file (which may or may not be related to the
880  * user-provided one, depending on the format).
881  */
883 
884  /**
885  * Decoding: pts of the first frame of the stream in presentation order, in stream time base.
886  * Only set this if you are absolutely 100% sure that the value you set
887  * it to really is the pts of the first frame.
888  * This may be undefined (AV_NOPTS_VALUE).
889  * @note The ASF header does NOT contain a correct start_time the ASF
890  * demuxer must NOT set this.
891  */
892  int64_t start_time;
893 
894  /**
895  * Decoding: duration of the stream, in stream time base.
896  * If a source file does not specify a duration, but does specify
897  * a bitrate, this value will be estimated from bitrate and file size.
898  *
899  * Encoding: May be set by the caller before avformat_write_header() to
900  * provide a hint to the muxer about the estimated duration.
901  */
902  int64_t duration;
903 
904  int64_t nb_frames; ///< number of frames in this stream if known or 0
905 
906  /**
907  * Stream disposition - a combination of AV_DISPOSITION_* flags.
908  * - demuxing: set by libavformat when creating the stream or in
909  * avformat_find_stream_info().
910  * - muxing: may be set by the caller before avformat_write_header().
911  */
913 
914  enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
915 
916  /**
917  * sample aspect ratio (0 if unknown)
918  * - encoding: Set by user.
919  * - decoding: Set by libavformat.
920  */
922 
924 
925  /**
926  * Average framerate
927  *
928  * - demuxing: May be set by libavformat when creating the stream or in
929  * avformat_find_stream_info().
930  * - muxing: May be set by the caller before avformat_write_header().
931  */
933 
934  /**
935  * For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet
936  * will contain the attached picture.
937  *
938  * decoding: set by libavformat, must not be modified by the caller.
939  * encoding: unused
940  */
942 
943 #if FF_API_AVSTREAM_SIDE_DATA
944  /**
945  * An array of side data that applies to the whole stream (i.e. the
946  * container does not allow it to change between packets).
947  *
948  * There may be no overlap between the side data in this array and side data
949  * in the packets. I.e. a given side data is either exported by the muxer
950  * (demuxing) / set by the caller (muxing) in this array, then it never
951  * appears in the packets, or the side data is exported / sent through
952  * the packets (always in the first packet where the value becomes known or
953  * changes), then it does not appear in this array.
954  *
955  * - demuxing: Set by libavformat when the stream is created.
956  * - muxing: May be set by the caller before avformat_write_header().
957  *
958  * Freed by libavformat in avformat_free_context().
959  *
960  * @deprecated use AVStream's @ref AVCodecParameters.coded_side_data
961  * "codecpar side data".
962  */
964  AVPacketSideData *side_data;
965  /**
966  * The number of elements in the AVStream.side_data array.
967  *
968  * @deprecated use AVStream's @ref AVCodecParameters.nb_coded_side_data
969  * "codecpar side data".
970  */
972  int nb_side_data;
973 #endif
974 
975  /**
976  * Flags indicating events happening on the stream, a combination of
977  * AVSTREAM_EVENT_FLAG_*.
978  *
979  * - demuxing: may be set by the demuxer in avformat_open_input(),
980  * avformat_find_stream_info() and av_read_frame(). Flags must be cleared
981  * by the user once the event has been handled.
982  * - muxing: may be set by the user after avformat_write_header(). to
983  * indicate a user-triggered event. The muxer will clear the flags for
984  * events it has handled in av_[interleaved]_write_frame().
985  */
986  int event_flags;
987 /**
988  * - demuxing: the demuxer read new metadata from the file and updated
989  * AVStream.metadata accordingly
990  * - muxing: the user updated AVStream.metadata and wishes the muxer to write
991  * it into the file
992  */
993 #define AVSTREAM_EVENT_FLAG_METADATA_UPDATED 0x0001
994 /**
995  * - demuxing: new packets for this stream were read from the file. This
996  * event is informational only and does not guarantee that new packets
997  * for this stream will necessarily be returned from av_read_frame().
998  */
999 #define AVSTREAM_EVENT_FLAG_NEW_PACKETS (1 << 1)
1000 
1001  /**
1002  * Real base framerate of the stream.
1003  * This is the lowest framerate with which all timestamps can be
1004  * represented accurately (it is the least common multiple of all
1005  * framerates in the stream). Note, this value is just a guess!
1006  * For example, if the time base is 1/90000 and all frames have either
1007  * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
1008  */
1010 
1011  /**
1012  * Number of bits in timestamps. Used for wrapping control.
1013  *
1014  * - demuxing: set by libavformat
1015  * - muxing: set by libavformat
1016  *
1017  */
1018  int pts_wrap_bits;
1019 } AVStream;
1020 
1021 /**
1022  * AVStreamGroupTileGrid holds information on how to combine several
1023  * independent images on a single canvas for presentation.
1024  *
1025  * The output should be a @ref AVStreamGroupTileGrid.background "background"
1026  * colored @ref AVStreamGroupTileGrid.coded_width "coded_width" x
1027  * @ref AVStreamGroupTileGrid.coded_height "coded_height" canvas where a
1028  * @ref AVStreamGroupTileGrid.nb_tiles "nb_tiles" amount of tiles are placed in
1029  * the order they appear in the @ref AVStreamGroupTileGrid.offsets "offsets"
1030  * array, at the exact offset described for them. In particular, if two or more
1031  * tiles overlap, the image with higher index in the
1032  * @ref AVStreamGroupTileGrid.offsets "offsets" array takes priority.
1033  * Note that a single image may be used multiple times, i.e. multiple entries
1034  * in @ref AVStreamGroupTileGrid.offsets "offsets" may have the same value of
1035  * idx.
1036  *
1037  * The following is an example of a simple grid with 3 rows and 4 columns:
1038  *
1039  * +---+---+---+---+
1040  * | 0 | 1 | 2 | 3 |
1041  * +---+---+---+---+
1042  * | 4 | 5 | 6 | 7 |
1043  * +---+---+---+---+
1044  * | 8 | 9 |10 |11 |
1045  * +---+---+---+---+
1046  *
1047  * Assuming all tiles have a dimension of 512x512, the
1048  * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
1049  * the first @ref AVStreamGroup.streams "stream" in the group is "0,0", the
1050  * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
1051  * the second @ref AVStreamGroup.streams "stream" in the group is "512,0", the
1052  * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
1053  * the fifth @ref AVStreamGroup.streams "stream" in the group is "0,512", the
1054  * @ref AVStreamGroupTileGrid.offsets "offset", of the topleft pixel of
1055  * the sixth @ref AVStreamGroup.streams "stream" in the group is "512,512",
1056  * etc.
1057  *
1058  * The following is an example of a canvas with overlaping tiles:
1059  *
1060  * +-----------+
1061  * | %%%%% |
1062  * |***%%3%%@@@|
1063  * |**0%%%%%2@@|
1064  * |***##1@@@@@|
1065  * | ##### |
1066  * +-----------+
1067  *
1068  * Assuming a canvas with size 1024x1024 and all tiles with a dimension of
1069  * 512x512, a possible @ref AVStreamGroupTileGrid.offsets "offset" for the
1070  * topleft pixel of the first @ref AVStreamGroup.streams "stream" in the group
1071  * would be 0x256, the @ref AVStreamGroupTileGrid.offsets "offset" for the
1072  * topleft pixel of the second @ref AVStreamGroup.streams "stream" in the group
1073  * would be 256x512, the @ref AVStreamGroupTileGrid.offsets "offset" for the
1074  * topleft pixel of the third @ref AVStreamGroup.streams "stream" in the group
1075  * would be 512x256, and the @ref AVStreamGroupTileGrid.offsets "offset" for
1076  * the topleft pixel of the fourth @ref AVStreamGroup.streams "stream" in the
1077  * group would be 256x0.
1078  *
1079  * sizeof(AVStreamGroupTileGrid) is not a part of the ABI and may only be
1080  * allocated by avformat_stream_group_create().
1081  */
1082 typedef struct AVStreamGroupTileGrid {
1083  const AVClass *av_class;
1084 
1085  /**
1086  * Amount of tiles in the grid.
1087  *
1088  * Must be > 0.
1089  */
1090  unsigned int nb_tiles;
1091 
1092  /**
1093  * Width of the canvas.
1094  *
1095  * Must be > 0.
1096  */
1097  int coded_width;
1098  /**
1099  * Width of the canvas.
1100  *
1101  * Must be > 0.
1102  */
1103  int coded_height;
1104 
1105  /**
1106  * An @ref nb_tiles sized array of offsets in pixels from the topleft edge
1107  * of the canvas, indicating where each stream should be placed.
1108  * It must be allocated with the av_malloc() family of functions.
1109  *
1110  * - demuxing: set by libavformat, must not be modified by the caller.
1111  * - muxing: set by the caller before avformat_write_header().
1112  *
1113  * Freed by libavformat in avformat_free_context().
1114  */
1115  struct {
1116  /**
1117  * Index of the stream in the group this tile references.
1118  *
1119  * Must be < @ref AVStreamGroup.nb_streams "nb_streams".
1120  */
1121  unsigned int idx;
1122  /**
1123  * Offset in pixels from the left edge of the canvas where the tile
1124  * should be placed.
1125  */
1126  int horizontal;
1127  /**
1128  * Offset in pixels from the top edge of the canvas where the tile
1129  * should be placed.
1130  */
1131  int vertical;
1132  } *offsets;
1133 
1134  /**
1135  * The pixel value per channel in RGBA format used if no pixel of any tile
1136  * is located at a particular pixel location.
1137  *
1138  * @see av_image_fill_color().
1139  * @see av_parse_color().
1140  */
1141  uint8_t background[4];
1142 
1143  /**
1144  * Offset in pixels from the left edge of the canvas where the actual image
1145  * meant for presentation starts.
1146  *
1147  * This field must be >= 0 and < @ref coded_width.
1148  */
1149  int horizontal_offset;
1150  /**
1151  * Offset in pixels from the top edge of the canvas where the actual image
1152  * meant for presentation starts.
1153  *
1154  * This field must be >= 0 and < @ref coded_height.
1155  */
1156  int vertical_offset;
1157 
1158  /**
1159  * Width of the final image for presentation.
1160  *
1161  * Must be > 0 and <= (@ref coded_width - @ref horizontal_offset).
1162  * When it's not equal to (@ref coded_width - @ref horizontal_offset), the
1163  * result of (@ref coded_width - width - @ref horizontal_offset) is the
1164  * amount amount of pixels to be cropped from the right edge of the
1165  * final image before presentation.
1166  */
1167  int width;
1168  /**
1169  * Height of the final image for presentation.
1170  *
1171  * Must be > 0 and <= (@ref coded_height - @ref vertical_offset).
1172  * When it's not equal to (@ref coded_height - @ref vertical_offset), the
1173  * result of (@ref coded_height - height - @ref vertical_offset) is the
1174  * amount amount of pixels to be cropped from the bottom edge of the
1175  * final image before presentation.
1176  */
1177  int height;
1185 };
1186 
1187 struct AVIAMFAudioElement;
1189 
1190 typedef struct AVStreamGroup {
1191  /**
1192  * A class for @ref avoptions. Set by avformat_stream_group_create().
1193  */
1195 
1196  void *priv_data;
1197 
1198  /**
1199  * Group index in AVFormatContext.
1200  */
1201  unsigned int index;
1202 
1203  /**
1204  * Group type-specific group ID.
1205  *
1206  * decoding: set by libavformat
1207  * encoding: may set by the user
1208  */
1209  int64_t id;
1210 
1211  /**
1212  * Group type
1213  *
1214  * decoding: set by libavformat on group creation
1215  * encoding: set by avformat_stream_group_create()
1216  */
1218 
1219  /**
1220  * Group type-specific parameters
1221  */
1222  union {
1226  } params;
1227 
1228  /**
1229  * Metadata that applies to the whole group.
1230  *
1231  * - demuxing: set by libavformat on group creation
1232  * - muxing: may be set by the caller before avformat_write_header()
1233  *
1234  * Freed by libavformat in avformat_free_context().
1235  */
1237 
1238  /**
1239  * Number of elements in AVStreamGroup.streams.
1240  *
1241  * Set by avformat_stream_group_add_stream() must not be modified by any other code.
1242  */
1243  unsigned int nb_streams;
1244 
1245  /**
1246  * A list of streams in the group. New entries are created with
1247  * avformat_stream_group_add_stream().
1248  *
1249  * - demuxing: entries are created by libavformat on group creation.
1250  * If AVFMTCTX_NOHEADER is set in ctx_flags, then new entries may also
1251  * appear in av_read_frame().
1252  * - muxing: entries are created by the user before avformat_write_header().
1253  *
1254  * Freed by libavformat in avformat_free_context().
1255  */
1256  AVStream **streams;
1257 
1258  /**
1259  * Stream group disposition - a combination of AV_DISPOSITION_* flags.
1260  * This field currently applies to all defined AVStreamGroupParamsType.
1261  *
1262  * - demuxing: set by libavformat when creating the group or in
1263  * avformat_find_stream_info().
1264  * - muxing: may be set by the caller before avformat_write_header().
1265  */
1266  int disposition;
1267 } AVStreamGroup;
1268 
1270 
1271 #if FF_API_GET_END_PTS
1272 /**
1273  * Returns the pts of the last muxed packet + its duration
1274  *
1275  * the retuned value is undefined when used with a demuxer.
1276  */
1278 int64_t av_stream_get_end_pts(const AVStream *st);
1279 #endif
1280 
1281 #define AV_PROGRAM_RUNNING 1
1282 
1283 /**
1284  * New fields can be added to the end with minor version bumps.
1285  * Removal, reordering and changes to existing fields require a major
1286  * version bump.
1287  * sizeof(AVProgram) must not be used outside libav*.
1288  */
1289 typedef struct AVProgram {
1290  int id;
1291  int flags;
1292  enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
1293  unsigned int *stream_index;
1294  unsigned int nb_stream_indexes;
1298  int pmt_pid;
1299  int pcr_pid;
1300  int pmt_version;
1301 
1302  /*****************************************************************
1303  * All fields below this line are not part of the public API. They
1304  * may not be used outside of libavformat and can be changed and
1305  * removed at will.
1306  * New public fields should be added right above.
1307  *****************************************************************
1308  */
1309  int64_t start_time;
1310  int64_t end_time;
1312  int64_t pts_wrap_reference; ///< reference dts for wrap detection
1313  int pts_wrap_behavior; ///< behavior on wrap detection
1315 
1316 #define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
1317  (streams are added dynamically) */
1318 #define AVFMTCTX_UNSEEKABLE 0x0002 /**< signal that the stream is definitely
1319  not seekable, and attempts to call the
1320  seek function will fail. For some
1321  network protocols (e.g. HLS), this can
1322  change dynamically at runtime. */
1324 typedef struct AVChapter {
1325  int64_t id; ///< unique ID to identify the chapter
1326  AVRational time_base; ///< time base in which the start/end timestamps are specified
1327  int64_t start, end; ///< chapter start/end time in time_base units
1329 } AVChapter;
1330 
1331 
1332 /**
1333  * Callback used by devices to communicate with application.
1334  */
1335 typedef int (*av_format_control_message)(struct AVFormatContext *s, int type,
1336  void *data, size_t data_size);
1337 
1338 typedef int (*AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags,
1340 
1341 /**
1342  * The duration of a video can be estimated through various ways, and this enum can be used
1343  * to know how the duration was estimated.
1344  */
1346  AVFMT_DURATION_FROM_PTS, ///< Duration accurately estimated from PTSes
1347  AVFMT_DURATION_FROM_STREAM, ///< Duration estimated from a stream with a known duration
1348  AVFMT_DURATION_FROM_BITRATE ///< Duration estimated from bitrate (less accurate)
1349 };
1350 
1351 /**
1352  * Format I/O context.
1353  * New fields can be added to the end with minor version bumps.
1354  * Removal, reordering and changes to existing fields require a major
1355  * version bump.
1356  * sizeof(AVFormatContext) must not be used outside libav*, use
1357  * avformat_alloc_context() to create an AVFormatContext.
1358  *
1359  * Fields can be accessed through AVOptions (av_opt*),
1360  * the name string used matches the associated command line parameter name and
1361  * can be found in libavformat/options_table.h.
1362  * The AVOption/command line parameter names differ in some cases from the C
1363  * structure field names for historic reasons or brevity.
1364  */
1365 typedef struct AVFormatContext {
1366  /**
1367  * A class for logging and @ref avoptions. Set by avformat_alloc_context().
1368  * Exports (de)muxer private options if they exist.
1369  */
1370  const AVClass *av_class;
1371 
1372  /**
1373  * The input container format.
1374  *
1375  * Demuxing only, set by avformat_open_input().
1376  */
1377  const struct AVInputFormat *iformat;
1378 
1379  /**
1380  * The output container format.
1381  *
1382  * Muxing only, must be set by the caller before avformat_write_header().
1383  */
1384  const struct AVOutputFormat *oformat;
1385 
1386  /**
1387  * Format private data. This is an AVOptions-enabled struct
1388  * if and only if iformat/oformat.priv_class is not NULL.
1389  *
1390  * - muxing: set by avformat_write_header()
1391  * - demuxing: set by avformat_open_input()
1392  */
1393  void *priv_data;
1394 
1395  /**
1396  * I/O context.
1397  *
1398  * - demuxing: either set by the user before avformat_open_input() (then
1399  * the user must close it manually) or set by avformat_open_input().
1400  * - muxing: set by the user before avformat_write_header(). The caller must
1401  * take care of closing / freeing the IO context.
1402  *
1403  * Do NOT set this field if AVFMT_NOFILE flag is set in
1404  * iformat/oformat.flags. In such a case, the (de)muxer will handle
1405  * I/O in some other way and this field will be NULL.
1406  */
1407  AVIOContext *pb;
1408 
1409  /* stream info */
1410  /**
1411  * Flags signalling stream properties. A combination of AVFMTCTX_*.
1412  * Set by libavformat.
1413  */
1414  int ctx_flags;
1415 
1416  /**
1417  * Number of elements in AVFormatContext.streams.
1418  *
1419  * Set by avformat_new_stream(), must not be modified by any other code.
1420  */
1421  unsigned int nb_streams;
1422  /**
1423  * A list of all streams in the file. New streams are created with
1424  * avformat_new_stream().
1425  *
1426  * - demuxing: streams are created by libavformat in avformat_open_input().
1427  * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
1428  * appear in av_read_frame().
1429  * - muxing: streams are created by the user before avformat_write_header().
1430  *
1431  * Freed by libavformat in avformat_free_context().
1432  */
1433  AVStream **streams;
1434 
1435  /**
1436  * input or output URL. Unlike the old filename field, this field has no
1437  * length restriction.
1438  *
1439  * - demuxing: set by avformat_open_input(), initialized to an empty
1440  * string if url parameter was NULL in avformat_open_input().
1441  * - muxing: may be set by the caller before calling avformat_write_header()
1442  * (or avformat_init_output() if that is called first) to a string
1443  * which is freeable by av_free(). Set to an empty string if it
1444  * was NULL in avformat_init_output().
1445  *
1446  * Freed by libavformat in avformat_free_context().
1447  */
1448  char *url;
1449 
1450  /**
1451  * Position of the first frame of the component, in
1452  * AV_TIME_BASE fractional seconds. NEVER set this value directly:
1453  * It is deduced from the AVStream values.
1454  *
1455  * Demuxing only, set by libavformat.
1456  */
1457  int64_t start_time;
1458 
1459  /**
1460  * Duration of the stream, in AV_TIME_BASE fractional
1461  * seconds. Only set this value if you know none of the individual stream
1462  * durations and also do not set any of them. This is deduced from the
1463  * AVStream values if not set.
1464  *
1465  * Demuxing only, set by libavformat.
1466  */
1467  int64_t duration;
1468 
1469  /**
1470  * Total stream bitrate in bit/s, 0 if not
1471  * available. Never set it directly if the file_size and the
1472  * duration are known as FFmpeg can compute it automatically.
1473  */
1474  int64_t bit_rate;
1476  unsigned int packet_size;
1477  int max_delay;
1478 
1479  /**
1480  * Flags modifying the (de)muxer behaviour. A combination of AVFMT_FLAG_*.
1481  * Set by the user before avformat_open_input() / avformat_write_header().
1482  */
1483  int flags;
1484 #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
1485 #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
1486 #define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
1487 #define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
1488 #define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
1489 #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
1490 #define AVFMT_FLAG_NOBUFFER 0x0040 ///< Do not buffer frames when possible
1491 #define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
1492 #define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted
1493 #define AVFMT_FLAG_FLUSH_PACKETS 0x0200 ///< Flush the AVIOContext every packet.
1494 /**
1495  * When muxing, try to avoid writing any random/volatile data to the output.
1496  * This includes any random IDs, real-time timestamps/dates, muxer version, etc.
1497  *
1498  * This flag is mainly intended for testing.
1499  */
1500 #define AVFMT_FLAG_BITEXACT 0x0400
1501 #define AVFMT_FLAG_SORT_DTS 0x10000 ///< try to interleave outputted packets by dts (using this flag can slow demuxing down)
1502 #define AVFMT_FLAG_FAST_SEEK 0x80000 ///< Enable fast, but inaccurate seeks for some formats
1503 #if FF_API_LAVF_SHORTEST
1504 #define AVFMT_FLAG_SHORTEST 0x100000 ///< Stop muxing when the shortest stream stops.
1505 #endif
1506 #define AVFMT_FLAG_AUTO_BSF 0x200000 ///< Add bitstream filters as requested by the muxer
1507 
1508  /**
1509  * Maximum number of bytes read from input in order to determine stream
1510  * properties. Used when reading the global header and in
1511  * avformat_find_stream_info().
1512  *
1513  * Demuxing only, set by the caller before avformat_open_input().
1514  *
1515  * @note this is \e not used for determining the \ref AVInputFormat
1516  * "input format"
1517  * @sa format_probesize
1518  */
1519  int64_t probesize;
1520 
1521  /**
1522  * Maximum duration (in AV_TIME_BASE units) of the data read
1523  * from input in avformat_find_stream_info().
1524  * Demuxing only, set by the caller before avformat_find_stream_info().
1525  * Can be set to 0 to let avformat choose using a heuristic.
1526  */
1529  const uint8_t *key;
1530  int keylen;
1532  unsigned int nb_programs;
1533  AVProgram **programs;
1534 
1535  /**
1536  * Forced video codec_id.
1537  * Demuxing: Set by user.
1538  */
1540 
1541  /**
1542  * Forced audio codec_id.
1543  * Demuxing: Set by user.
1544  */
1546 
1547  /**
1548  * Forced subtitle codec_id.
1549  * Demuxing: Set by user.
1550  */
1552 
1553  /**
1554  * Maximum amount of memory in bytes to use for the index of each stream.
1555  * If the index exceeds this size, entries will be discarded as
1556  * needed to maintain a smaller size. This can lead to slower or less
1557  * accurate seeking (depends on demuxer).
1558  * Demuxers for which a full in-memory index is mandatory will ignore
1559  * this.
1560  * - muxing: unused
1561  * - demuxing: set by user
1562  */
1563  unsigned int max_index_size;
1564 
1565  /**
1566  * Maximum amount of memory in bytes to use for buffering frames
1567  * obtained from realtime capture devices.
1568  */
1569  unsigned int max_picture_buffer;
1570 
1571  /**
1572  * Number of chapters in AVChapter array.
1573  * When muxing, chapters are normally written in the file header,
1574  * so nb_chapters should normally be initialized before write_header
1575  * is called. Some muxers (e.g. mov and mkv) can also write chapters
1576  * in the trailer. To write chapters in the trailer, nb_chapters
1577  * must be zero when write_header is called and non-zero when
1578  * write_trailer is called.
1579  * - muxing: set by user
1580  * - demuxing: set by libavformat
1581  */
1582  unsigned int nb_chapters;
1583  AVChapter **chapters;
1584 
1585  /**
1586  * Metadata that applies to the whole file.
1587  *
1588  * - demuxing: set by libavformat in avformat_open_input()
1589  * - muxing: may be set by the caller before avformat_write_header()
1590  *
1591  * Freed by libavformat in avformat_free_context().
1592  */
1594 
1595  /**
1596  * Start time of the stream in real world time, in microseconds
1597  * since the Unix epoch (00:00 1st January 1970). That is, pts=0 in the
1598  * stream was captured at this real world time.
1599  * - muxing: Set by the caller before avformat_write_header(). If set to
1600  * either 0 or AV_NOPTS_VALUE, then the current wall-time will
1601  * be used.
1602  * - demuxing: Set by libavformat. AV_NOPTS_VALUE if unknown. Note that
1603  * the value may become known after some number of frames
1604  * have been received.
1605  */
1606  int64_t start_time_realtime;
1607 
1608  /**
1609  * The number of frames used for determining the framerate in
1610  * avformat_find_stream_info().
1611  * Demuxing only, set by the caller before avformat_find_stream_info().
1612  */
1613  int fps_probe_size;
1614 
1615  /**
1616  * Error recognition; higher values will detect more errors but may
1617  * misdetect some more or less valid parts as errors.
1618  * Demuxing only, set by the caller before avformat_open_input().
1619  */
1620  int error_recognition;
1621 
1622  /**
1623  * Custom interrupt callbacks for the I/O layer.
1624  *
1625  * demuxing: set by the user before avformat_open_input().
1626  * muxing: set by the user before avformat_write_header()
1627  * (mainly useful for AVFMT_NOFILE formats). The callback
1628  * should also be passed to avio_open2() if it's used to
1629  * open the file.
1630  */
1632 
1633  /**
1634  * Flags to enable debugging.
1635  */
1636  int debug;
1637 #define FF_FDEBUG_TS 0x0001
1638 
1639  /**
1640  * Maximum buffering duration for interleaving.
1641  *
1642  * To ensure all the streams are interleaved correctly,
1643  * av_interleaved_write_frame() will wait until it has at least one packet
1644  * for each stream before actually writing any packets to the output file.
1645  * When some streams are "sparse" (i.e. there are large gaps between
1646  * successive packets), this can result in excessive buffering.
1647  *
1648  * This field specifies the maximum difference between the timestamps of the
1649  * first and the last packet in the muxing queue, above which libavformat
1650  * will output a packet regardless of whether it has queued a packet for all
1651  * the streams.
1652  *
1653  * Muxing only, set by the caller before avformat_write_header().
1654  */
1655  int64_t max_interleave_delta;
1656 
1657  /**
1658  * Allow non-standard and experimental extension
1659  * @see AVCodecContext.strict_std_compliance
1660  */
1662 
1663  /**
1664  * Flags indicating events happening on the file, a combination of
1665  * AVFMT_EVENT_FLAG_*.
1666  *
1667  * - demuxing: may be set by the demuxer in avformat_open_input(),
1668  * avformat_find_stream_info() and av_read_frame(). Flags must be cleared
1669  * by the user once the event has been handled.
1670  * - muxing: may be set by the user after avformat_write_header() to
1671  * indicate a user-triggered event. The muxer will clear the flags for
1672  * events it has handled in av_[interleaved]_write_frame().
1673  */
1674  int event_flags;
1675 /**
1676  * - demuxing: the demuxer read new metadata from the file and updated
1677  * AVFormatContext.metadata accordingly
1678  * - muxing: the user updated AVFormatContext.metadata and wishes the muxer to
1679  * write it into the file
1680  */
1681 #define AVFMT_EVENT_FLAG_METADATA_UPDATED 0x0001
1682 
1683  /**
1684  * Maximum number of packets to read while waiting for the first timestamp.
1685  * Decoding only.
1686  */
1687  int max_ts_probe;
1688 
1689  /**
1690  * Avoid negative timestamps during muxing.
1691  * Any value of the AVFMT_AVOID_NEG_TS_* constants.
1692  * Note, this works better when using av_interleaved_write_frame().
1693  * - muxing: Set by user
1694  * - demuxing: unused
1695  */
1697 #define AVFMT_AVOID_NEG_TS_AUTO -1 ///< Enabled when required by target format
1698 #define AVFMT_AVOID_NEG_TS_DISABLED 0 ///< Do not shift timestamps even when they are negative.
1699 #define AVFMT_AVOID_NEG_TS_MAKE_NON_NEGATIVE 1 ///< Shift timestamps so they are non negative
1700 #define AVFMT_AVOID_NEG_TS_MAKE_ZERO 2 ///< Shift timestamps so that they start at 0
1701 
1702  /**
1703  * Transport stream id.
1704  * This will be moved into demuxer private options. Thus no API/ABI compatibility
1705  */
1706  int ts_id;
1707 
1708  /**
1709  * Audio preload in microseconds.
1710  * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1711  * - encoding: Set by user
1712  * - decoding: unused
1713  */
1714  int audio_preload;
1715 
1716  /**
1717  * Max chunk time in microseconds.
1718  * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1719  * - encoding: Set by user
1720  * - decoding: unused
1721  */
1722  int max_chunk_duration;
1723 
1724  /**
1725  * Max chunk size in bytes
1726  * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1727  * - encoding: Set by user
1728  * - decoding: unused
1729  */
1730  int max_chunk_size;
1731 
1732  /**
1733  * forces the use of wallclock timestamps as pts/dts of packets
1734  * This has undefined results in the presence of B frames.
1735  * - encoding: unused
1736  * - decoding: Set by user
1737  */
1739 
1740  /**
1741  * avio flags, used to force AVIO_FLAG_DIRECT.
1742  * - encoding: unused
1743  * - decoding: Set by user
1744  */
1745  int avio_flags;
1746 
1747  /**
1748  * The duration field can be estimated through various ways, and this field can be used
1749  * to know how the duration was estimated.
1750  * - encoding: unused
1751  * - decoding: Read by user
1752  */
1754 
1755  /**
1756  * Skip initial bytes when opening stream
1757  * - encoding: unused
1758  * - decoding: Set by user
1759  */
1760  int64_t skip_initial_bytes;
1761 
1762  /**
1763  * Correct single timestamp overflows
1764  * - encoding: unused
1765  * - decoding: Set by user
1766  */
1767  unsigned int correct_ts_overflow;
1768 
1769  /**
1770  * Force seeking to any (also non key) frames.
1771  * - encoding: unused
1772  * - decoding: Set by user
1773  */
1774  int seek2any;
1775 
1776  /**
1777  * Flush the I/O context after each packet.
1778  * - encoding: Set by user
1779  * - decoding: unused
1780  */
1781  int flush_packets;
1782 
1783  /**
1784  * format probing score.
1785  * The maximal score is AVPROBE_SCORE_MAX, its set when the demuxer probes
1786  * the format.
1787  * - encoding: unused
1788  * - decoding: set by avformat, read by user
1789  */
1790  int probe_score;
1791 
1792  /**
1793  * Maximum number of bytes read from input in order to identify the
1794  * \ref AVInputFormat "input format". Only used when the format is not set
1795  * explicitly by the caller.
1796  *
1797  * Demuxing only, set by the caller before avformat_open_input().
1798  *
1799  * @sa probesize
1800  */
1801  int format_probesize;
1802 
1803  /**
1804  * ',' separated list of allowed decoders.
1805  * If NULL then all are allowed
1806  * - encoding: unused
1807  * - decoding: set by user
1808  */
1809  char *codec_whitelist;
1810 
1811  /**
1812  * ',' separated list of allowed demuxers.
1813  * If NULL then all are allowed
1814  * - encoding: unused
1815  * - decoding: set by user
1816  */
1817  char *format_whitelist;
1818 
1819  /**
1820  * IO repositioned flag.
1821  * This is set by avformat when the underlaying IO context read pointer
1822  * is repositioned, for example when doing byte based seeking.
1823  * Demuxers can use the flag to detect such changes.
1824  */
1825  int io_repositioned;
1826 
1827  /**
1828  * Forced video codec.
1829  * This allows forcing a specific decoder, even when there are multiple with
1830  * the same codec_id.
1831  * Demuxing: Set by user
1832  */
1833  const struct AVCodec *video_codec;
1834 
1835  /**
1836  * Forced audio codec.
1837  * This allows forcing a specific decoder, even when there are multiple with
1838  * the same codec_id.
1839  * Demuxing: Set by user
1840  */
1841  const struct AVCodec *audio_codec;
1842 
1843  /**
1844  * Forced subtitle codec.
1845  * This allows forcing a specific decoder, even when there are multiple with
1846  * the same codec_id.
1847  * Demuxing: Set by user
1848  */
1849  const struct AVCodec *subtitle_codec;
1850 
1851  /**
1852  * Forced data codec.
1853  * This allows forcing a specific decoder, even when there are multiple with
1854  * the same codec_id.
1855  * Demuxing: Set by user
1856  */
1857  const struct AVCodec *data_codec;
1858 
1859  /**
1860  * Number of bytes to be written as padding in a metadata header.
1861  * Demuxing: Unused.
1862  * Muxing: Set by user.
1863  */
1865 
1866  /**
1867  * User data.
1868  * This is a place for some private data of the user.
1869  */
1870  void *opaque;
1871 
1872  /**
1873  * Callback used by devices to communicate with application.
1874  */
1876 
1877  /**
1878  * Output timestamp offset, in microseconds.
1879  * Muxing: set by user
1880  */
1881  int64_t output_ts_offset;
1882 
1883  /**
1884  * dump format separator.
1885  * can be ", " or "\n " or anything else
1886  * - muxing: Set by user.
1887  * - demuxing: Set by user.
1888  */
1889  uint8_t *dump_separator;
1890 
1891  /**
1892  * Forced Data codec_id.
1893  * Demuxing: Set by user.
1894  */
1895  enum AVCodecID data_codec_id;
1896 
1897  /**
1898  * ',' separated list of allowed protocols.
1899  * - encoding: unused
1900  * - decoding: set by user
1901  */
1902  char *protocol_whitelist;
1903 
1904  /**
1905  * A callback for opening new IO streams.
1906  *
1907  * Whenever a muxer or a demuxer needs to open an IO stream (typically from
1908  * avformat_open_input() for demuxers, but for certain formats can happen at
1909  * other times as well), it will call this callback to obtain an IO context.
1910  *
1911  * @param s the format context
1912  * @param pb on success, the newly opened IO context should be returned here
1913  * @param url the url to open
1914  * @param flags a combination of AVIO_FLAG_*
1915  * @param options a dictionary of additional options, with the same
1916  * semantics as in avio_open2()
1917  * @return 0 on success, a negative AVERROR code on failure
1918  *
1919  * @note Certain muxers and demuxers do nesting, i.e. they open one or more
1920  * additional internal format contexts. Thus the AVFormatContext pointer
1921  * passed to this callback may be different from the one facing the caller.
1922  * It will, however, have the same 'opaque' field.
1923  */
1924  int (*io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url,
1925  int flags, AVDictionary **options);
1926 
1927 #if FF_API_AVFORMAT_IO_CLOSE
1928  /**
1929  * A callback for closing the streams opened with AVFormatContext.io_open().
1930  *
1931  * @deprecated use io_close2
1932  */
1934  void (*io_close)(struct AVFormatContext *s, AVIOContext *pb);
1935 #endif
1936 
1937  /**
1938  * ',' separated list of disallowed protocols.
1939  * - encoding: unused
1940  * - decoding: set by user
1941  */
1942  char *protocol_blacklist;
1943 
1944  /**
1945  * The maximum number of streams.
1946  * - encoding: unused
1947  * - decoding: set by user
1948  */
1949  int max_streams;
1950 
1951  /**
1952  * Skip duration calcuation in estimate_timings_from_pts.
1953  * - encoding: unused
1954  * - decoding: set by user
1955  */
1957 
1958  /**
1959  * Maximum number of packets that can be probed
1960  * - encoding: unused
1961  * - decoding: set by user
1962  */
1963  int max_probe_packets;
1964 
1965  /**
1966  * A callback for closing the streams opened with AVFormatContext.io_open().
1967  *
1968  * Using this is preferred over io_close, because this can return an error.
1969  * Therefore this callback is used instead of io_close by the generic
1970  * libavformat code if io_close is NULL or the default.
1971  *
1972  * @param s the format context
1973  * @param pb IO context to be closed and freed
1974  * @return 0 on success, a negative AVERROR code on failure
1975  */
1976  int (*io_close2)(struct AVFormatContext *s, AVIOContext *pb);
1977 
1978  /**
1979  * Number of elements in AVFormatContext.stream_groups.
1980  *
1981  * Set by avformat_stream_group_create(), must not be modified by any other code.
1982  */
1983  unsigned int nb_stream_groups;
1984 
1985  /**
1986  * A list of all stream groups in the file. New groups are created with
1987  * avformat_stream_group_create(), and filled with avformat_stream_group_add_stream().
1988  *
1989  * - demuxing: groups may be created by libavformat in avformat_open_input().
1990  * If AVFMTCTX_NOHEADER is set in ctx_flags, then new groups may also
1991  * appear in av_read_frame().
1992  * - muxing: groups may be created by the user before avformat_write_header().
1993  *
1994  * Freed by libavformat in avformat_free_context().
1995  */
1997 } AVFormatContext;
1998 
1999 /**
2000  * This function will cause global side data to be injected in the next packet
2001  * of each stream as well as after any subsequent seek.
2002  *
2003  * @note global side data is always available in every AVStream's
2004  * @ref AVCodecParameters.coded_side_data "codecpar side data" array, and
2005  * in a @ref AVCodecContext.coded_side_data "decoder's side data" array if
2006  * initialized with said stream's codecpar.
2007  * @see av_packet_side_data_get()
2008  */
2010 
2011 /**
2012  * Returns the method used to set ctx->duration.
2013  *
2014  * @return AVFMT_DURATION_FROM_PTS, AVFMT_DURATION_FROM_STREAM, or AVFMT_DURATION_FROM_BITRATE.
2015  */
2017 
2018 /**
2019  * @defgroup lavf_core Core functions
2020  * @ingroup libavf
2021  *
2022  * Functions for querying libavformat capabilities, allocating core structures,
2023  * etc.
2024  * @{
2025  */
2026 
2027 /**
2028  * Return the LIBAVFORMAT_VERSION_INT constant.
2029  */
2030 unsigned avformat_version(void);
2031 
2032 /**
2033  * Return the libavformat build-time configuration.
2034  */
2035 const char *avformat_configuration(void);
2036 
2037 /**
2038  * Return the libavformat license.
2039  */
2040 const char *avformat_license(void);
2041 
2042 /**
2043  * Do global initialization of network libraries. This is optional,
2044  * and not recommended anymore.
2045  *
2046  * This functions only exists to work around thread-safety issues
2047  * with older GnuTLS or OpenSSL libraries. If libavformat is linked
2048  * to newer versions of those libraries, or if you do not use them,
2049  * calling this function is unnecessary. Otherwise, you need to call
2050  * this function before any other threads using them are started.
2051  *
2052  * This function will be deprecated once support for older GnuTLS and
2053  * OpenSSL libraries is removed, and this function has no purpose
2054  * anymore.
2055  */
2056 int avformat_network_init(void);
2057 
2058 /**
2059  * Undo the initialization done by avformat_network_init. Call it only
2060  * once for each time you called avformat_network_init.
2061  */
2062 int avformat_network_deinit(void);
2063 
2064 /**
2065  * Iterate over all registered muxers.
2066  *
2067  * @param opaque a pointer where libavformat will store the iteration state. Must
2068  * point to NULL to start the iteration.
2069  *
2070  * @return the next registered muxer or NULL when the iteration is
2071  * finished
2072  */
2073 const AVOutputFormat *av_muxer_iterate(void **opaque);
2074 
2075 /**
2076  * Iterate over all registered demuxers.
2077  *
2078  * @param opaque a pointer where libavformat will store the iteration state.
2079  * Must point to NULL to start the iteration.
2080  *
2081  * @return the next registered demuxer or NULL when the iteration is
2082  * finished
2083  */
2084 const AVInputFormat *av_demuxer_iterate(void **opaque);
2085 
2086 /**
2087  * Allocate an AVFormatContext.
2088  * avformat_free_context() can be used to free the context and everything
2089  * allocated by the framework within it.
2090  */
2092 
2093 /**
2094  * Free an AVFormatContext and all its streams.
2095  * @param s context to free
2096  */
2098 
2099 /**
2100  * Get the AVClass for AVFormatContext. It can be used in combination with
2101  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2102  *
2103  * @see av_opt_find().
2104  */
2105 const AVClass *avformat_get_class(void);
2106 
2107 /**
2108  * Get the AVClass for AVStream. It can be used in combination with
2109  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2110  *
2111  * @see av_opt_find().
2112  */
2113 const AVClass *av_stream_get_class(void);
2114 
2115 /**
2116  * Get the AVClass for AVStreamGroup. It can be used in combination with
2117  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2118  *
2119  * @see av_opt_find().
2120  */
2121 const AVClass *av_stream_group_get_class(void);
2122 
2123 /**
2124  * Add a new empty stream group to a media file.
2125  *
2126  * When demuxing, it may be called by the demuxer in read_header(). If the
2127  * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
2128  * be called in read_packet().
2129  *
2130  * When muxing, may be called by the user before avformat_write_header().
2131  *
2132  * User is required to call avformat_free_context() to clean up the allocation
2133  * by avformat_stream_group_create().
2134  *
2135  * New streams can be added to the group with avformat_stream_group_add_stream().
2136  *
2137  * @param s media file handle
2138  *
2139  * @return newly created group or NULL on error.
2140  * @see avformat_new_stream, avformat_stream_group_add_stream.
2141  */
2144  AVDictionary **options);
2145 
2146 /**
2147  * Add a new stream to a media file.
2148  *
2149  * When demuxing, it is called by the demuxer in read_header(). If the
2150  * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
2151  * be called in read_packet().
2152  *
2153  * When muxing, should be called by the user before avformat_write_header().
2154  *
2155  * User is required to call avformat_free_context() to clean up the allocation
2156  * by avformat_new_stream().
2157  *
2158  * @param s media file handle
2159  * @param c unused, does nothing
2160  *
2161  * @return newly created stream or NULL on error.
2162  */
2164 
2165 /**
2166  * Add an already allocated stream to a stream group.
2167  *
2168  * When demuxing, it may be called by the demuxer in read_header(). If the
2169  * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
2170  * be called in read_packet().
2171  *
2172  * When muxing, may be called by the user before avformat_write_header() after
2173  * having allocated a new group with avformat_stream_group_create() and stream with
2174  * avformat_new_stream().
2175  *
2176  * User is required to call avformat_free_context() to clean up the allocation
2177  * by avformat_stream_group_add_stream().
2178  *
2179  * @param stg stream group belonging to a media file.
2180  * @param st stream in the media file to add to the group.
2181  *
2182  * @retval 0 success
2183  * @retval AVERROR(EEXIST) the stream was already in the group
2184  * @retval "another negative error code" legitimate errors
2185  *
2186  * @see avformat_new_stream, avformat_stream_group_create.
2187  */
2189 
2190 #if FF_API_AVSTREAM_SIDE_DATA
2191 /**
2192  * Wrap an existing array as stream side data.
2193  *
2194  * @param st stream
2195  * @param type side information type
2196  * @param data the side data array. It must be allocated with the av_malloc()
2197  * family of functions. The ownership of the data is transferred to
2198  * st.
2199  * @param size side information size
2200  *
2201  * @return zero on success, a negative AVERROR code on failure. On failure,
2202  * the stream is unchanged and the data remains owned by the caller.
2203  * @deprecated use av_packet_side_data_add() with the stream's
2204  * @ref AVCodecParameters.coded_side_data "codecpar side data"
2205  */
2207 int av_stream_add_side_data(AVStream *st, enum AVPacketSideDataType type,
2208  uint8_t *data, size_t size);
2209 
2210 /**
2211  * Allocate new information from stream.
2212  *
2213  * @param stream stream
2214  * @param type desired side information type
2215  * @param size side information size
2216  *
2217  * @return pointer to fresh allocated data or NULL otherwise
2218  * @deprecated use av_packet_side_data_new() with the stream's
2219  * @ref AVCodecParameters.coded_side_data "codecpar side data"
2220  */
2222 uint8_t *av_stream_new_side_data(AVStream *stream,
2223  enum AVPacketSideDataType type, size_t size);
2224 /**
2225  * Get side information from stream.
2226  *
2227  * @param stream stream
2228  * @param type desired side information type
2229  * @param size If supplied, *size will be set to the size of the side data
2230  * or to zero if the desired side data is not present.
2231  *
2232  * @return pointer to data if present or NULL otherwise
2233  * @deprecated use av_packet_side_data_get() with the stream's
2234  * @ref AVCodecParameters.coded_side_data "codecpar side data"
2235  */
2237 uint8_t *av_stream_get_side_data(const AVStream *stream,
2238  enum AVPacketSideDataType type, size_t *size);
2239 #endif
2240 
2242 
2243 /**
2244  * @}
2245  */
2246 
2247 
2248 /**
2249  * Allocate an AVFormatContext for an output format.
2250  * avformat_free_context() can be used to free the context and
2251  * everything allocated by the framework within it.
2252  *
2253  * @param ctx pointee is set to the created format context,
2254  * or to NULL in case of failure
2255  * @param oformat format to use for allocating the context, if NULL
2256  * format_name and filename are used instead
2257  * @param format_name the name of output format to use for allocating the
2258  * context, if NULL filename is used instead
2259  * @param filename the name of the filename to use for allocating the
2260  * context, may be NULL
2261  *
2262  * @return >= 0 in case of success, a negative AVERROR code in case of
2263  * failure
2264  */
2266  const char *format_name, const char *filename);
2267 
2268 /**
2269  * @addtogroup lavf_decoding
2270  * @{
2271  */
2272 
2273 /**
2274  * Find AVInputFormat based on the short name of the input format.
2275  */
2276 const AVInputFormat *av_find_input_format(const char *short_name);
2277 
2278 /**
2279  * Guess the file format.
2280  *
2281  * @param pd data to be probed
2282  * @param is_opened Whether the file is already opened; determines whether
2283  * demuxers with or without AVFMT_NOFILE are probed.
2284  */
2285 const AVInputFormat *av_probe_input_format(const AVProbeData *pd, int is_opened);
2286 
2287 /**
2288  * Guess the file format.
2289  *
2290  * @param pd data to be probed
2291  * @param is_opened Whether the file is already opened; determines whether
2292  * demuxers with or without AVFMT_NOFILE are probed.
2293  * @param score_max A probe score larger that this is required to accept a
2294  * detection, the variable is set to the actual detection
2295  * score afterwards.
2296  * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
2297  * to retry with a larger probe buffer.
2298  */
2300  int is_opened, int *score_max);
2301 
2302 /**
2303  * Guess the file format.
2304  *
2305  * @param is_opened Whether the file is already opened; determines whether
2306  * demuxers with or without AVFMT_NOFILE are probed.
2307  * @param score_ret The score of the best detection.
2308  */
2310  int is_opened, int *score_ret);
2311 
2312 /**
2313  * Probe a bytestream to determine the input format. Each time a probe returns
2314  * with a score that is too low, the probe buffer size is increased and another
2315  * attempt is made. When the maximum probe size is reached, the input format
2316  * with the highest score is returned.
2317  *
2318  * @param pb the bytestream to probe
2319  * @param fmt the input format is put here
2320  * @param url the url of the stream
2321  * @param logctx the log context
2322  * @param offset the offset within the bytestream to probe from
2323  * @param max_probe_size the maximum probe buffer size (zero for default)
2324  *
2325  * @return the score in case of success, a negative value corresponding to an
2326  * the maximal score is AVPROBE_SCORE_MAX
2327  * AVERROR code otherwise
2328  */
2330  const char *url, void *logctx,
2331  unsigned int offset, unsigned int max_probe_size);
2332 
2333 /**
2334  * Like av_probe_input_buffer2() but returns 0 on success
2335  */
2337  const char *url, void *logctx,
2338  unsigned int offset, unsigned int max_probe_size);
2339 
2340 /**
2341  * Open an input stream and read the header. The codecs are not opened.
2342  * The stream must be closed with avformat_close_input().
2343  *
2344  * @param ps Pointer to user-supplied AVFormatContext (allocated by
2345  * avformat_alloc_context). May be a pointer to NULL, in
2346  * which case an AVFormatContext is allocated by this
2347  * function and written into ps.
2348  * Note that a user-supplied AVFormatContext will be freed
2349  * on failure.
2350  * @param url URL of the stream to open.
2351  * @param fmt If non-NULL, this parameter forces a specific input format.
2352  * Otherwise the format is autodetected.
2353  * @param options A dictionary filled with AVFormatContext and demuxer-private
2354  * options.
2355  * On return this parameter will be destroyed and replaced with
2356  * a dict containing options that were not found. May be NULL.
2357  *
2358  * @return 0 on success, a negative AVERROR on failure.
2359  *
2360  * @note If you want to use custom IO, preallocate the format context and set its pb field.
2361  */
2362 int avformat_open_input(AVFormatContext **ps, const char *url,
2363  const AVInputFormat *fmt, AVDictionary **options);
2364 
2365 /**
2366  * Read packets of a media file to get stream information. This
2367  * is useful for file formats with no headers such as MPEG. This
2368  * function also computes the real framerate in case of MPEG-2 repeat
2369  * frame mode.
2370  * The logical file position is not changed by this function;
2371  * examined packets may be buffered for later processing.
2372  *
2373  * @param ic media file handle
2374  * @param options If non-NULL, an ic.nb_streams long array of pointers to
2375  * dictionaries, where i-th member contains options for
2376  * codec corresponding to i-th stream.
2377  * On return each dictionary will be filled with options that were not found.
2378  * @return >=0 if OK, AVERROR_xxx on error
2379  *
2380  * @note this function isn't guaranteed to open all the codecs, so
2381  * options being non-empty at return is a perfectly normal behavior.
2382  *
2383  * @todo Let the user decide somehow what information is needed so that
2384  * we do not waste time getting stuff the user does not need.
2385  */
2387 
2388 /**
2389  * Find the programs which belong to a given stream.
2390  *
2391  * @param ic media file handle
2392  * @param last the last found program, the search will start after this
2393  * program, or from the beginning if it is NULL
2394  * @param s stream index
2395  *
2396  * @return the next program which belongs to s, NULL if no program is found or
2397  * the last program is not among the programs of ic.
2398  */
2400 
2401 void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx);
2402 
2403 /**
2404  * Find the "best" stream in the file.
2405  * The best stream is determined according to various heuristics as the most
2406  * likely to be what the user expects.
2407  * If the decoder parameter is non-NULL, av_find_best_stream will find the
2408  * default decoder for the stream's codec; streams for which no decoder can
2409  * be found are ignored.
2410  *
2411  * @param ic media file handle
2412  * @param type stream type: video, audio, subtitles, etc.
2413  * @param wanted_stream_nb user-requested stream number,
2414  * or -1 for automatic selection
2415  * @param related_stream try to find a stream related (eg. in the same
2416  * program) to this one, or -1 if none
2417  * @param decoder_ret if non-NULL, returns the decoder for the
2418  * selected stream
2419  * @param flags flags; none are currently defined
2420  *
2421  * @return the non-negative stream number in case of success,
2422  * AVERROR_STREAM_NOT_FOUND if no stream with the requested type
2423  * could be found,
2424  * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
2425  *
2426  * @note If av_find_best_stream returns successfully and decoder_ret is not
2427  * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
2428  */
2430  enum AVMediaType type,
2431  int wanted_stream_nb,
2432  int related_stream,
2433  const struct AVCodec **decoder_ret,
2434  int flags);
2435 
2436 /**
2437  * Return the next frame of a stream.
2438  * This function returns what is stored in the file, and does not validate
2439  * that what is there are valid frames for the decoder. It will split what is
2440  * stored in the file into frames and return one for each call. It will not
2441  * omit invalid data between valid frames so as to give the decoder the maximum
2442  * information possible for decoding.
2443  *
2444  * On success, the returned packet is reference-counted (pkt->buf is set) and
2445  * valid indefinitely. The packet must be freed with av_packet_unref() when
2446  * it is no longer needed. For video, the packet contains exactly one frame.
2447  * For audio, it contains an integer number of frames if each frame has
2448  * a known fixed size (e.g. PCM or ADPCM data). If the audio frames have
2449  * a variable size (e.g. MPEG audio), then it contains one frame.
2450  *
2451  * pkt->pts, pkt->dts and pkt->duration are always set to correct
2452  * values in AVStream.time_base units (and guessed if the format cannot
2453  * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
2454  * has B-frames, so it is better to rely on pkt->dts if you do not
2455  * decompress the payload.
2456  *
2457  * @return 0 if OK, < 0 on error or end of file. On error, pkt will be blank
2458  * (as if it came from av_packet_alloc()).
2459  *
2460  * @note pkt will be initialized, so it may be uninitialized, but it must not
2461  * contain data that needs to be freed.
2462  */
2464 
2465 /**
2466  * Seek to the keyframe at timestamp.
2467  * 'timestamp' in 'stream_index'.
2468  *
2469  * @param s media file handle
2470  * @param stream_index If stream_index is (-1), a default stream is selected,
2471  * and timestamp is automatically converted from
2472  * AV_TIME_BASE units to the stream specific time_base.
2473  * @param timestamp Timestamp in AVStream.time_base units or, if no stream
2474  * is specified, in AV_TIME_BASE units.
2475  * @param flags flags which select direction and seeking mode
2476  *
2477  * @return >= 0 on success
2478  */
2479 int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
2480  int flags);
2481 
2482 /**
2483  * Seek to timestamp ts.
2484  * Seeking will be done so that the point from which all active streams
2485  * can be presented successfully will be closest to ts and within min/max_ts.
2486  * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
2487  *
2488  * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
2489  * are the file position (this may not be supported by all demuxers).
2490  * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
2491  * in the stream with stream_index (this may not be supported by all demuxers).
2492  * Otherwise all timestamps are in units of the stream selected by stream_index
2493  * or if stream_index is -1, in AV_TIME_BASE units.
2494  * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
2495  * keyframes (this may not be supported by all demuxers).
2496  * If flags contain AVSEEK_FLAG_BACKWARD, it is ignored.
2497  *
2498  * @param s media file handle
2499  * @param stream_index index of the stream which is used as time base reference
2500  * @param min_ts smallest acceptable timestamp
2501  * @param ts target timestamp
2502  * @param max_ts largest acceptable timestamp
2503  * @param flags flags
2504  * @return >=0 on success, error code otherwise
2505  *
2506  * @note This is part of the new seek API which is still under construction.
2507  */
2508 int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
2509 
2510 /**
2511  * Discard all internally buffered data. This can be useful when dealing with
2512  * discontinuities in the byte stream. Generally works only with formats that
2513  * can resync. This includes headerless formats like MPEG-TS/TS but should also
2514  * work with NUT, Ogg and in a limited way AVI for example.
2515  *
2516  * The set of streams, the detected duration, stream parameters and codecs do
2517  * not change when calling this function. If you want a complete reset, it's
2518  * better to open a new AVFormatContext.
2519  *
2520  * This does not flush the AVIOContext (s->pb). If necessary, call
2521  * avio_flush(s->pb) before calling this function.
2522  *
2523  * @param s media file handle
2524  * @return >=0 on success, error code otherwise
2525  */
2527 
2528 /**
2529  * Start playing a network-based stream (e.g. RTSP stream) at the
2530  * current position.
2531  */
2533 
2534 /**
2535  * Pause a network-based stream (e.g. RTSP stream).
2536  *
2537  * Use av_read_play() to resume it.
2538  */
2540 
2541 /**
2542  * Close an opened input AVFormatContext. Free it and all its contents
2543  * and set *s to NULL.
2544  */
2546 /**
2547  * @}
2548  */
2550 #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
2551 #define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
2552 #define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
2553 #define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
2554 
2555 /**
2556  * @addtogroup lavf_encoding
2557  * @{
2558  */
2560 #define AVSTREAM_INIT_IN_WRITE_HEADER 0 ///< stream parameters initialized in avformat_write_header
2561 #define AVSTREAM_INIT_IN_INIT_OUTPUT 1 ///< stream parameters initialized in avformat_init_output
2562 
2563 /**
2564  * Allocate the stream private data and write the stream header to
2565  * an output media file.
2566  *
2567  * @param s Media file handle, must be allocated with
2568  * avformat_alloc_context().
2569  * Its \ref AVFormatContext.oformat "oformat" field must be set
2570  * to the desired output format;
2571  * Its \ref AVFormatContext.pb "pb" field must be set to an
2572  * already opened ::AVIOContext.
2573  * @param options An ::AVDictionary filled with AVFormatContext and
2574  * muxer-private options.
2575  * On return this parameter will be destroyed and replaced with
2576  * a dict containing options that were not found. May be NULL.
2577  *
2578  * @retval AVSTREAM_INIT_IN_WRITE_HEADER On success, if the codec had not already been
2579  * fully initialized in avformat_init_output().
2580  * @retval AVSTREAM_INIT_IN_INIT_OUTPUT On success, if the codec had already been fully
2581  * initialized in avformat_init_output().
2582  * @retval AVERROR A negative AVERROR on failure.
2583  *
2584  * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_init_output.
2585  */
2588 
2589 /**
2590  * Allocate the stream private data and initialize the codec, but do not write the header.
2591  * May optionally be used before avformat_write_header() to initialize stream parameters
2592  * before actually writing the header.
2593  * If using this function, do not pass the same options to avformat_write_header().
2594  *
2595  * @param s Media file handle, must be allocated with
2596  * avformat_alloc_context().
2597  * Its \ref AVFormatContext.oformat "oformat" field must be set
2598  * to the desired output format;
2599  * Its \ref AVFormatContext.pb "pb" field must be set to an
2600  * already opened ::AVIOContext.
2601  * @param options An ::AVDictionary filled with AVFormatContext and
2602  * muxer-private options.
2603  * On return this parameter will be destroyed and replaced with
2604  * a dict containing options that were not found. May be NULL.
2605  *
2606  * @retval AVSTREAM_INIT_IN_WRITE_HEADER On success, if the codec requires
2607  * avformat_write_header to fully initialize.
2608  * @retval AVSTREAM_INIT_IN_INIT_OUTPUT On success, if the codec has been fully
2609  * initialized.
2610  * @retval AVERROR Anegative AVERROR on failure.
2611  *
2612  * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_write_header.
2613  */
2616 
2617 /**
2618  * Write a packet to an output media file.
2619  *
2620  * This function passes the packet directly to the muxer, without any buffering
2621  * or reordering. The caller is responsible for correctly interleaving the
2622  * packets if the format requires it. Callers that want libavformat to handle
2623  * the interleaving should call av_interleaved_write_frame() instead of this
2624  * function.
2625  *
2626  * @param s media file handle
2627  * @param pkt The packet containing the data to be written. Note that unlike
2628  * av_interleaved_write_frame(), this function does not take
2629  * ownership of the packet passed to it (though some muxers may make
2630  * an internal reference to the input packet).
2631  * <br>
2632  * This parameter can be NULL (at any time, not just at the end), in
2633  * order to immediately flush data buffered within the muxer, for
2634  * muxers that buffer up data internally before writing it to the
2635  * output.
2636  * <br>
2637  * Packet's @ref AVPacket.stream_index "stream_index" field must be
2638  * set to the index of the corresponding stream in @ref
2639  * AVFormatContext.streams "s->streams".
2640  * <br>
2641  * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2642  * must be set to correct values in the stream's timebase (unless the
2643  * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2644  * they can be set to AV_NOPTS_VALUE).
2645  * The dts for subsequent packets passed to this function must be strictly
2646  * increasing when compared in their respective timebases (unless the
2647  * output format is flagged with the AVFMT_TS_NONSTRICT, then they
2648  * merely have to be nondecreasing). @ref AVPacket.duration
2649  * "duration") should also be set if known.
2650  * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush
2651  *
2652  * @see av_interleaved_write_frame()
2653  */
2655 
2656 /**
2657  * Write a packet to an output media file ensuring correct interleaving.
2658  *
2659  * This function will buffer the packets internally as needed to make sure the
2660  * packets in the output file are properly interleaved, usually ordered by
2661  * increasing dts. Callers doing their own interleaving should call
2662  * av_write_frame() instead of this function.
2663  *
2664  * Using this function instead of av_write_frame() can give muxers advance
2665  * knowledge of future packets, improving e.g. the behaviour of the mp4
2666  * muxer for VFR content in fragmenting mode.
2667  *
2668  * @param s media file handle
2669  * @param pkt The packet containing the data to be written.
2670  * <br>
2671  * If the packet is reference-counted, this function will take
2672  * ownership of this reference and unreference it later when it sees
2673  * fit. If the packet is not reference-counted, libavformat will
2674  * make a copy.
2675  * The returned packet will be blank (as if returned from
2676  * av_packet_alloc()), even on error.
2677  * <br>
2678  * This parameter can be NULL (at any time, not just at the end), to
2679  * flush the interleaving queues.
2680  * <br>
2681  * Packet's @ref AVPacket.stream_index "stream_index" field must be
2682  * set to the index of the corresponding stream in @ref
2683  * AVFormatContext.streams "s->streams".
2684  * <br>
2685  * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2686  * must be set to correct values in the stream's timebase (unless the
2687  * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2688  * they can be set to AV_NOPTS_VALUE).
2689  * The dts for subsequent packets in one stream must be strictly
2690  * increasing (unless the output format is flagged with the
2691  * AVFMT_TS_NONSTRICT, then they merely have to be nondecreasing).
2692  * @ref AVPacket.duration "duration" should also be set if known.
2693  *
2694  * @return 0 on success, a negative AVERROR on error.
2695  *
2696  * @see av_write_frame(), AVFormatContext.max_interleave_delta
2697  */
2699 
2700 /**
2701  * Write an uncoded frame to an output media file.
2702  *
2703  * The frame must be correctly interleaved according to the container
2704  * specification; if not, av_interleaved_write_uncoded_frame() must be used.
2705  *
2706  * See av_interleaved_write_uncoded_frame() for details.
2707  */
2708 int av_write_uncoded_frame(AVFormatContext *s, int stream_index,
2709  struct AVFrame *frame);
2710 
2711 /**
2712  * Write an uncoded frame to an output media file.
2713  *
2714  * If the muxer supports it, this function makes it possible to write an AVFrame
2715  * structure directly, without encoding it into a packet.
2716  * It is mostly useful for devices and similar special muxers that use raw
2717  * video or PCM data and will not serialize it into a byte stream.
2718  *
2719  * To test whether it is possible to use it with a given muxer and stream,
2720  * use av_write_uncoded_frame_query().
2721  *
2722  * The caller gives up ownership of the frame and must not access it
2723  * afterwards.
2724  *
2725  * @return >=0 for success, a negative code on error
2726  */
2728  struct AVFrame *frame);
2729 
2730 /**
2731  * Test whether a muxer supports uncoded frame.
2732  *
2733  * @return >=0 if an uncoded frame can be written to that muxer and stream,
2734  * <0 if not
2735  */
2736 int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index);
2737 
2738 /**
2739  * Write the stream trailer to an output media file and free the
2740  * file private data.
2741  *
2742  * May only be called after a successful call to avformat_write_header.
2743  *
2744  * @param s media file handle
2745  * @return 0 if OK, AVERROR_xxx on error
2746  */
2748 
2749 /**
2750  * Return the output format in the list of registered output formats
2751  * which best matches the provided parameters, or return NULL if
2752  * there is no match.
2753  *
2754  * @param short_name if non-NULL checks if short_name matches with the
2755  * names of the registered formats
2756  * @param filename if non-NULL checks if filename terminates with the
2757  * extensions of the registered formats
2758  * @param mime_type if non-NULL checks if mime_type matches with the
2759  * MIME type of the registered formats
2760  */
2761 const AVOutputFormat *av_guess_format(const char *short_name,
2762  const char *filename,
2763  const char *mime_type);
2764 
2765 /**
2766  * Guess the codec ID based upon muxer and filename.
2767  */
2768 enum AVCodecID av_guess_codec(const AVOutputFormat *fmt, const char *short_name,
2769  const char *filename, const char *mime_type,
2770  enum AVMediaType type);
2771 
2772 /**
2773  * Get timing information for the data currently output.
2774  * The exact meaning of "currently output" depends on the format.
2775  * It is mostly relevant for devices that have an internal buffer and/or
2776  * work in real time.
2777  * @param s media file handle
2778  * @param stream stream in the media file
2779  * @param[out] dts DTS of the last packet output for the stream, in stream
2780  * time_base units
2781  * @param[out] wall absolute time when that packet whas output,
2782  * in microsecond
2783  * @retval 0 Success
2784  * @retval AVERROR(ENOSYS) The format does not support it
2785  *
2786  * @note Some formats or devices may not allow to measure dts and wall
2787  * atomically.
2788  */
2789 int av_get_output_timestamp(struct AVFormatContext *s, int stream,
2790  int64_t *dts, int64_t *wall);
2791 
2792 
2793 /**
2794  * @}
2795  */
2796 
2797 
2798 /**
2799  * @defgroup lavf_misc Utility functions
2800  * @ingroup libavf
2801  * @{
2802  *
2803  * Miscellaneous utility functions related to both muxing and demuxing
2804  * (or neither).
2805  */
2806 
2807 /**
2808  * Send a nice hexadecimal dump of a buffer to the specified file stream.
2809  *
2810  * @param f The file stream pointer where the dump should be sent to.
2811  * @param buf buffer
2812  * @param size buffer size
2813  *
2814  * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2
2815  */
2816 void av_hex_dump(FILE *f, const uint8_t *buf, int size);
2817 
2818 /**
2819  * Send a nice hexadecimal dump of a buffer to the log.
2820  *
2821  * @param avcl A pointer to an arbitrary struct of which the first field is a
2822  * pointer to an AVClass struct.
2823  * @param level The importance level of the message, lower values signifying
2824  * higher importance.
2825  * @param buf buffer
2826  * @param size buffer size
2827  *
2828  * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2
2829  */
2830 void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size);
2831 
2832 /**
2833  * Send a nice dump of a packet to the specified file stream.
2834  *
2835  * @param f The file stream pointer where the dump should be sent to.
2836  * @param pkt packet to dump
2837  * @param dump_payload True if the payload must be displayed, too.
2838  * @param st AVStream that the packet belongs to
2839  */
2840 void av_pkt_dump2(FILE *f, const AVPacket *pkt, int dump_payload, const AVStream *st);
2841 
2842 
2843 /**
2844  * Send a nice dump of a packet to the log.
2845  *
2846  * @param avcl A pointer to an arbitrary struct of which the first field is a
2847  * pointer to an AVClass struct.
2848  * @param level The importance level of the message, lower values signifying
2849  * higher importance.
2850  * @param pkt packet to dump
2851  * @param dump_payload True if the payload must be displayed, too.
2852  * @param st AVStream that the packet belongs to
2853  */
2854 void av_pkt_dump_log2(void *avcl, int level, const AVPacket *pkt, int dump_payload,
2855  const AVStream *st);
2856 
2857 /**
2858  * Get the AVCodecID for the given codec tag tag.
2859  * If no codec id is found returns AV_CODEC_ID_NONE.
2860  *
2861  * @param tags list of supported codec_id-codec_tag pairs, as stored
2862  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2863  * @param tag codec tag to match to a codec ID
2864  */
2865 enum AVCodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
2866 
2867 /**
2868  * Get the codec tag for the given codec id id.
2869  * If no codec tag is found returns 0.
2870  *
2871  * @param tags list of supported codec_id-codec_tag pairs, as stored
2872  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2873  * @param id codec ID to match to a codec tag
2874  */
2875 unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id);
2876 
2877 /**
2878  * Get the codec tag for the given codec id.
2879  *
2880  * @param tags list of supported codec_id - codec_tag pairs, as stored
2881  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2882  * @param id codec id that should be searched for in the list
2883  * @param tag A pointer to the found tag
2884  * @return 0 if id was not found in tags, > 0 if it was found
2885  */
2886 int av_codec_get_tag2(const struct AVCodecTag * const *tags, enum AVCodecID id,
2887  unsigned int *tag);
2888 
2890 
2891 /**
2892  * Get the index for a specific timestamp.
2893  *
2894  * @param st stream that the timestamp belongs to
2895  * @param timestamp timestamp to retrieve the index for
2896  * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
2897  * to the timestamp which is <= the requested one, if backward
2898  * is 0, then it will be >=
2899  * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
2900  * @return < 0 if no such timestamp could be found
2901  */
2902 int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
2903 
2904 /**
2905  * Get the index entry count for the given AVStream.
2906  *
2907  * @param st stream
2908  * @return the number of index entries in the stream
2909  */
2911 
2912 /**
2913  * Get the AVIndexEntry corresponding to the given index.
2914  *
2915  * @param st Stream containing the requested AVIndexEntry.
2916  * @param idx The desired index.
2917  * @return A pointer to the requested AVIndexEntry if it exists, NULL otherwise.
2918  *
2919  * @note The pointer returned by this function is only guaranteed to be valid
2920  * until any function that takes the stream or the parent AVFormatContext
2921  * as input argument is called.
2922  */
2923 const AVIndexEntry *avformat_index_get_entry(AVStream *st, int idx);
2924 
2925 /**
2926  * Get the AVIndexEntry corresponding to the given timestamp.
2927  *
2928  * @param st Stream containing the requested AVIndexEntry.
2929  * @param wanted_timestamp Timestamp to retrieve the index entry for.
2930  * @param flags If AVSEEK_FLAG_BACKWARD then the returned entry will correspond
2931  * to the timestamp which is <= the requested one, if backward
2932  * is 0, then it will be >=
2933  * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise.
2934  * @return A pointer to the requested AVIndexEntry if it exists, NULL otherwise.
2935  *
2936  * @note The pointer returned by this function is only guaranteed to be valid
2937  * until any function that takes the stream or the parent AVFormatContext
2938  * as input argument is called.
2939  */
2941  int64_t wanted_timestamp,
2942  int flags);
2943 /**
2944  * Add an index entry into a sorted list. Update the entry if the list
2945  * already contains it.
2946  *
2947  * @param timestamp timestamp in the time base of the given stream
2948  */
2949 int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
2950  int size, int distance, int flags);
2951 
2952 
2953 /**
2954  * Split a URL string into components.
2955  *
2956  * The pointers to buffers for storing individual components may be null,
2957  * in order to ignore that component. Buffers for components not found are
2958  * set to empty strings. If the port is not found, it is set to a negative
2959  * value.
2960  *
2961  * @param proto the buffer for the protocol
2962  * @param proto_size the size of the proto buffer
2963  * @param authorization the buffer for the authorization
2964  * @param authorization_size the size of the authorization buffer
2965  * @param hostname the buffer for the host name
2966  * @param hostname_size the size of the hostname buffer
2967  * @param port_ptr a pointer to store the port number in
2968  * @param path the buffer for the path
2969  * @param path_size the size of the path buffer
2970  * @param url the URL to split
2971  */
2972 void av_url_split(char *proto, int proto_size,
2973  char *authorization, int authorization_size,
2974  char *hostname, int hostname_size,
2975  int *port_ptr,
2976  char *path, int path_size,
2977  const char *url);
2978 
2979 
2980 /**
2981  * Print detailed information about the input or output format, such as
2982  * duration, bitrate, streams, container, programs, metadata, side data,
2983  * codec and time base.
2984  *
2985  * @param ic the context to analyze
2986  * @param index index of the stream to dump information about
2987  * @param url the URL to print, such as source or destination file
2988  * @param is_output Select whether the specified context is an input(0) or output(1)
2989  */
2991  int index,
2992  const char *url,
2993  int is_output);
2995 
2996 #define AV_FRAME_FILENAME_FLAGS_MULTIPLE 1 ///< Allow multiple %d
2997 
2998 /**
2999  * Return in 'buf' the path with '%d' replaced by a number.
3000  *
3001  * Also handles the '%0nd' format where 'n' is the total number
3002  * of digits and '%%'.
3003  *
3004  * @param buf destination buffer
3005  * @param buf_size destination buffer size
3006  * @param path numbered sequence string
3007  * @param number frame number
3008  * @param flags AV_FRAME_FILENAME_FLAGS_*
3009  * @return 0 if OK, -1 on format error
3010  */
3011 int av_get_frame_filename2(char *buf, int buf_size,
3012  const char *path, int number, int flags);
3013 
3014 int av_get_frame_filename(char *buf, int buf_size,
3015  const char *path, int number);
3016 
3017 /**
3018  * Check whether filename actually is a numbered sequence generator.
3019  *
3020  * @param filename possible numbered sequence string
3021  * @return 1 if a valid numbered sequence string, 0 otherwise
3022  */
3023 int av_filename_number_test(const char *filename);
3024 
3025 /**
3026  * Generate an SDP for an RTP session.
3027  *
3028  * Note, this overwrites the id values of AVStreams in the muxer contexts
3029  * for getting unique dynamic payload types.
3030  *
3031  * @param ac array of AVFormatContexts describing the RTP streams. If the
3032  * array is composed by only one context, such context can contain
3033  * multiple AVStreams (one AVStream per RTP stream). Otherwise,
3034  * all the contexts in the array (an AVCodecContext per RTP stream)
3035  * must contain only one AVStream.
3036  * @param n_files number of AVCodecContexts contained in ac
3037  * @param buf buffer where the SDP will be stored (must be allocated by
3038  * the caller)
3039  * @param size the size of the buffer
3040  * @return 0 if OK, AVERROR_xxx on error
3041  */
3042 int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size);
3043 
3044 /**
3045  * Return a positive value if the given filename has one of the given
3046  * extensions, 0 otherwise.
3047  *
3048  * @param filename file name to check against the given extensions
3049  * @param extensions a comma-separated list of filename extensions
3050  */
3051 int av_match_ext(const char *filename, const char *extensions);
3052 
3053 /**
3054  * Test if the given container can store a codec.
3055  *
3056  * @param ofmt container to check for compatibility
3057  * @param codec_id codec to potentially store in container
3058  * @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
3059  *
3060  * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
3061  * A negative number if this information is not available.
3062  */
3064  int std_compliance);
3065 
3066 /**
3067  * @defgroup riff_fourcc RIFF FourCCs
3068  * @{
3069  * Get the tables mapping RIFF FourCCs to libavcodec AVCodecIDs. The tables are
3070  * meant to be passed to av_codec_get_id()/av_codec_get_tag() as in the
3071  * following code:
3072  * @code
3073  * uint32_t tag = MKTAG('H', '2', '6', '4');
3074  * const struct AVCodecTag *table[] = { avformat_get_riff_video_tags(), 0 };
3075  * enum AVCodecID id = av_codec_get_id(table, tag);
3076  * @endcode
3077  */
3078 /**
3079  * @return the table mapping RIFF FourCCs for video to libavcodec AVCodecID.
3080  */
3081 const struct AVCodecTag *avformat_get_riff_video_tags(void);
3082 /**
3083  * @return the table mapping RIFF FourCCs for audio to AVCodecID.
3084  */
3085 const struct AVCodecTag *avformat_get_riff_audio_tags(void);
3086 /**
3087  * @return the table mapping MOV FourCCs for video to libavcodec AVCodecID.
3088  */
3089 const struct AVCodecTag *avformat_get_mov_video_tags(void);
3090 /**
3091  * @return the table mapping MOV FourCCs for audio to AVCodecID.
3092  */
3093 const struct AVCodecTag *avformat_get_mov_audio_tags(void);
3094 
3095 /**
3096  * @}
3097  */
3098 
3099 /**
3100  * Guess the sample aspect ratio of a frame, based on both the stream and the
3101  * frame aspect ratio.
3102  *
3103  * Since the frame aspect ratio is set by the codec but the stream aspect ratio
3104  * is set by the demuxer, these two may not be equal. This function tries to
3105  * return the value that you should use if you would like to display the frame.
3106  *
3107  * Basic logic is to use the stream aspect ratio if it is set to something sane
3108  * otherwise use the frame aspect ratio. This way a container setting, which is
3109  * usually easy to modify can override the coded value in the frames.
3110  *
3111  * @param format the format context which the stream is part of
3112  * @param stream the stream which the frame is part of
3113  * @param frame the frame with the aspect ratio to be determined
3114  * @return the guessed (valid) sample_aspect_ratio, 0/1 if no idea
3115  */
3117  struct AVFrame *frame);
3118 
3119 /**
3120  * Guess the frame rate, based on both the container and codec information.
3121  *
3122  * @param ctx the format context which the stream is part of
3123  * @param stream the stream which the frame is part of
3124  * @param frame the frame for which the frame rate should be determined, may be NULL
3125  * @return the guessed (valid) frame rate, 0/1 if no idea
3126  */
3128  struct AVFrame *frame);
3129 
3130 /**
3131  * Check if the stream st contained in s is matched by the stream specifier
3132  * spec.
3133  *
3134  * See the "stream specifiers" chapter in the documentation for the syntax
3135  * of spec.
3136  *
3137  * @return >0 if st is matched by spec;
3138  * 0 if st is not matched by spec;
3139  * AVERROR code if spec is invalid
3140  *
3141  * @note A stream specifier can match several streams in the format.
3142  */
3144  const char *spec);
3145 
3152 #if FF_API_R_FRAME_RATE
3153  AVFMT_TBCF_R_FRAMERATE,
3154 #endif
3155 };
3156 
3157 /**
3158  * Transfer internal timing information from one stream to another.
3159  *
3160  * This function is useful when doing stream copy.
3161  *
3162  * @param ofmt target output format for ost
3163  * @param ost output stream which needs timings copy and adjustments
3164  * @param ist reference input stream to copy timings from
3165  * @param copy_tb define from where the stream codec timebase needs to be imported
3166  */
3168  AVStream *ost, const AVStream *ist,
3169  enum AVTimebaseSource copy_tb);
3170 
3171 /**
3172  * Get the internal codec timebase from a stream.
3173  *
3174  * @param st input stream to extract the timebase from
3175  */
3177 
3178 /**
3179  * @}
3180  */
3181 
3182 #endif /* AVFORMAT_AVFORMAT_H */
avformat_get_riff_video_tags
const struct AVCodecTag * avformat_get_riff_video_tags(void)
Definition: riff.c:638
AVFormatContext::control_message_cb
av_format_control_message control_message_cb
Callback used by devices to communicate with application.
Definition: avformat.h:1873
av_pkt_dump2
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:115
AVCodec
AVCodec.
Definition: codec.h:187
AVStreamGroupParamsType
AVStreamGroupParamsType
Definition: avformat.h:1178
av_codec_get_id
enum AVCodecID av_codec_get_id(const struct AVCodecTag *const *tags, unsigned int tag)
Get the AVCodecID for the given codec tag tag.
AVFormatContext::stream_groups
AVStreamGroup ** stream_groups
A list of all stream groups in the file.
Definition: avformat.h:1994
av_format_control_message
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:1333
level
uint8_t level
Definition: svq3.c:204
AVStreamGroup::id
int64_t id
Group type-specific group ID.
Definition: avformat.h:1207
av_fmt_ctx_get_duration_estimation_method
enum AVDurationEstimationMethod av_fmt_ctx_get_duration_estimation_method(const AVFormatContext *ctx)
Returns the method used to set ctx->duration.
Definition: options.c:201
AVFMT_DURATION_FROM_BITRATE
@ AVFMT_DURATION_FROM_BITRATE
Duration estimated from bitrate (less accurate)
Definition: avformat.h:1346
AVOutputFormat::extensions
const char * extensions
comma-separated filename extensions
Definition: avformat.h:519
AVOutputFormat::name
const char * name
Definition: avformat.h:511
AVChapter::metadata
AVDictionary * metadata
Definition: avformat.h:1326
AVStreamGroup::tile_grid
struct AVStreamGroupTileGrid * tile_grid
Definition: avformat.h:1223
av_probe_input_buffer2
int av_probe_input_buffer2(AVIOContext *pb, const 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:251
AVInputFormat::raw_codec_id
int raw_codec_id
Raw demuxers store their codec ID here.
Definition: avformat.h:598
AVProgram::nb_stream_indexes
unsigned int nb_stream_indexes
Definition: avformat.h:1292
AVFormatContext::max_chunk_duration
int max_chunk_duration
Max chunk time in microseconds.
Definition: avformat.h:1720
AVFormatContext::max_index_size
unsigned int max_index_size
Maximum amount of memory in bytes to use for the index of each stream.
Definition: avformat.h:1561
AVFormatContext::nb_chapters
unsigned int nb_chapters
Number of chapters in AVChapter array.
Definition: avformat.h:1580
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:47
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVStream::priv_data
void * priv_data
Definition: avformat.h:866
AVStreamGroupTileGrid::horizontal_offset
int horizontal_offset
Offset in pixels from the left edge of the canvas where the actual image meant for presentation start...
Definition: avformat.h:1147
AVStream::discard
enum AVDiscard discard
Selects which packets can be discarded at will and do not need to be demuxed.
Definition: avformat.h:912
av_find_program_from_stream
AVProgram * av_find_program_from_stream(AVFormatContext *ic, AVProgram *last, int s)
Find the programs which belong to a given stream.
Definition: avformat.c:382
AVFormatContext::audio_preload
int audio_preload
Audio preload in microseconds.
Definition: avformat.h:1712
AVFormatContext::protocol_blacklist
char * protocol_blacklist
',' separated list of disallowed protocols.
Definition: avformat.h:1940
AVFMT_TBCF_DECODER
@ AVFMT_TBCF_DECODER
Definition: avformat.h:3148
AVProgram::pmt_version
int pmt_version
Definition: avformat.h:1298
avformat_get_class
const AVClass * avformat_get_class(void)
Get the AVClass for AVFormatContext.
Definition: options.c:206
AVStreamGroup::disposition
int disposition
Stream group disposition - a combination of AV_DISPOSITION_* flags.
Definition: avformat.h:1264
AVFMT_TBCF_AUTO
@ AVFMT_TBCF_AUTO
Definition: avformat.h:3147
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1431
AVPacketSideData
This structure stores auxiliary information for decoding, presenting, or otherwise processing the cod...
Definition: packet.h:373
AVFormatContext::strict_std_compliance
int strict_std_compliance
Allow non-standard and experimental extension.
Definition: avformat.h:1659
av_disposition_to_string
const char * av_disposition_to_string(int disposition)
Definition: options.c:533
av_get_frame_filename2
int av_get_frame_filename2(char *buf, int buf_size, const char *path, int number, int flags)
Return in 'buf' the path with 'd' replaced by a number.
Definition: utils.c:295
AVStreamGroupTileGrid::offsets
struct AVStreamGroupTileGrid::@294 * offsets
An nb_tiles sized array of offsets in pixels from the topleft edge of the canvas, indicating where ea...
AVFormatContext::max_interleave_delta
int64_t max_interleave_delta
Maximum buffering duration for interleaving.
Definition: avformat.h:1653
AVStream::avg_frame_rate
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:930
AVStreamGroupTileGrid::vertical_offset
int vertical_offset
Offset in pixels from the top edge of the canvas where the actual image meant for presentation starts...
Definition: avformat.h:1154
AVChapter::start
int64_t start
Definition: avformat.h:1325
data
const char data[16]
Definition: mxf.c:148
AVFormatContext::duration_estimation_method
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:1751
AVFMT_TBCF_DEMUXER
@ AVFMT_TBCF_DEMUXER
Definition: avformat.h:3149
AVFormatContext::programs
AVProgram ** programs
Definition: avformat.h:1531
AVDictionary
Definition: dict.c:34
AVProgram::flags
int flags
Definition: avformat.h:1289
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:455
AVStreamGroupTileGrid::vertical
int vertical
Offset in pixels from the top edge of the canvas where the tile should be placed.
Definition: avformat.h:1129
AVFormatContext::probesize
int64_t probesize
Maximum number of bytes read from input in order to determine stream properties.
Definition: avformat.h:1517
av_write_uncoded_frame_query
int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index)
Test whether a muxer supports uncoded frame.
Definition: mux.c:1483
avformat_init_output
av_warn_unused_result int avformat_init_output(AVFormatContext *s, AVDictionary **options)
Allocate the stream private data and initialize the codec, but do not write the header.
Definition: mux.c:451
av_read_frame
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: demux.c:1558
AVFormatContext::video_codec_id
enum AVCodecID video_codec_id
Forced video codec_id.
Definition: avformat.h:1537
avformat_index_get_entry_from_timestamp
const AVIndexEntry * avformat_index_get_entry_from_timestamp(AVStream *st, int64_t wanted_timestamp, int flags)
Get the AVIndexEntry corresponding to the given timestamp.
Definition: seek.c:264
av_get_frame_filename
int av_get_frame_filename(char *buf, int buf_size, const char *path, int number)
Definition: utils.c:353
ost
static AVStream * ost
Definition: vaapi_transcode.c:42
AVIndexEntry
Definition: avformat.h:700
AVOutputFormat::subtitle_codec
enum AVCodecID subtitle_codec
default subtitle codec
Definition: avformat.h:523
AVIOInterruptCB
Callback for checking whether to abort blocking functions.
Definition: avio.h:59
AVProgram::pmt_pid
int pmt_pid
Definition: avformat.h:1296
AVInputFormat::long_name
const char * long_name
Descriptive name for the format, meant to be more human-readable than name.
Definition: avformat.h:561
av_filename_number_test
int av_filename_number_test(const char *filename)
Check whether filename actually is a numbered sequence generator.
Definition: utils.c:126
avformat_queue_attached_pictures
int avformat_queue_attached_pictures(AVFormatContext *s)
Definition: demux_utils.c:93
avformat_close_input
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: demux.c:374
AVFormatContext::interrupt_callback
AVIOInterruptCB interrupt_callback
Custom interrupt callbacks for the I/O layer.
Definition: avformat.h:1629
AVFormatContext::flush_packets
int flush_packets
Flush the I/O context after each packet.
Definition: avformat.h:1779
AVStreamGroup::av_class
const AVClass * av_class
A class for AVOptions.
Definition: avformat.h:1192
avformat_get_mov_video_tags
const struct AVCodecTag * avformat_get_mov_video_tags(void)
Definition: isom_tags.c:357
AVFormatContext::max_picture_buffer
unsigned int max_picture_buffer
Maximum amount of memory in bytes to use for buffering frames obtained from realtime capture devices.
Definition: avformat.h:1567
AVStreamGroupTileGrid
AVStreamGroupTileGrid holds information on how to combine several independent images on a single canv...
Definition: avformat.h:1080
av_add_index_entry
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: seek.c:120
AVSTREAM_PARSE_FULL_ONCE
@ AVSTREAM_PARSE_FULL_ONCE
full parsing and repack of the first frame only, only implemented for H.264 currently
Definition: avformat.h:694
avformat_version
unsigned avformat_version(void)
Return the LIBAVFORMAT_VERSION_INT constant.
Definition: version.c:30
AVStreamParseType
AVStreamParseType
Definition: avformat.h:689
AVStreamGroupTileGrid::coded_width
int coded_width
Width of the canvas.
Definition: avformat.h:1095
AVProgram::discard
enum AVDiscard discard
selects which program to discard and which to feed to the caller
Definition: avformat.h:1290
AVChapter
Definition: avformat.h:1322
AVFormatContext::dump_separator
uint8_t * dump_separator
dump format separator.
Definition: avformat.h:1887
av_stream_group_get_class
const AVClass * av_stream_group_get_class(void)
Get the AVClass for AVStreamGroup.
Definition: options.c:426
AVFMT_DURATION_FROM_PTS
@ AVFMT_DURATION_FROM_PTS
Duration accurately estimated from PTSes.
Definition: avformat.h:1344
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
AVStreamGroupTileGrid::coded_height
int coded_height
Width of the canvas.
Definition: avformat.h:1101
av_new_program
AVProgram * av_new_program(AVFormatContext *s, int id)
Definition: avformat.c:324
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:900
av_codec_get_tag2
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.
av_probe_input_format3
const AVInputFormat * av_probe_input_format3(const AVProbeData *pd, int is_opened, int *score_ret)
Guess the file format.
Definition: format.c:154
codec.h
avformat_network_init
int avformat_network_init(void)
Do global initialization of network libraries.
Definition: utils.c:558
AVFormatContext::event_flags
int event_flags
Flags indicating events happening on the file, a combination of AVFMT_EVENT_FLAG_*.
Definition: avformat.h:1672
AVStream::attached_pic
AVPacket attached_pic
For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet will contain the attached pictu...
Definition: avformat.h:939
AVStreamGroupTileGrid::av_class
const AVClass * av_class
Definition: avformat.h:1081
avformat_get_riff_audio_tags
const struct AVCodecTag * avformat_get_riff_audio_tags(void)
Definition: riff.c:643
AVFormatContext::bit_rate
int64_t bit_rate
Total stream bitrate in bit/s, 0 if not available.
Definition: avformat.h:1472
AVFormatContext::max_ts_probe
int max_ts_probe
Maximum number of packets to read while waiting for the first timestamp.
Definition: avformat.h:1685
AVFormatContext::format_whitelist
char * format_whitelist
',' separated list of allowed demuxers.
Definition: avformat.h:1815
AVFormatContext::format_probesize
int format_probesize
Maximum number of bytes read from input in order to identify the input format.
Definition: avformat.h:1799
pkt
AVPacket * pkt
Definition: movenc.c:59
avformat_index_get_entries_count
int avformat_index_get_entries_count(const AVStream *st)
Get the index entry count for the given AVStream.
Definition: seek.c:250
AVFormatContext::metadata
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1591
AVInputFormat
Definition: avformat.h:549
AVProbeData::mime_type
const char * mime_type
mime_type, when known.
Definition: avformat.h:456
AVInputFormat::extensions
const char * extensions
If extensions are defined, then no probe is done.
Definition: avformat.h:575
av_dump_format
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,...
Definition: dump.c:785
AVCodecTag
Definition: internal.h:48
AVFormatContext::ctx_flags
int ctx_flags
Flags signalling stream properties.
Definition: avformat.h:1412
AVProgram::id
int id
Definition: avformat.h:1288
avformat_open_input
int avformat_open_input(AVFormatContext **ps, const char *url, const AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: demux.c:226
avformat_query_codec
int avformat_query_codec(const AVOutputFormat *ofmt, enum AVCodecID codec_id, int std_compliance)
Test if the given container can store a codec.
Definition: mux_utils.c:40
AV_STREAM_GROUP_PARAMS_IAMF_MIX_PRESENTATION
@ AV_STREAM_GROUP_PARAMS_IAMF_MIX_PRESENTATION
Definition: avformat.h:1181
AVChapter::end
int64_t end
chapter start/end time in time_base units
Definition: avformat.h:1325
AVFormatContext::video_codec
const struct AVCodec * video_codec
Forced video codec.
Definition: avformat.h:1831
s
#define s(width, name)
Definition: cbs_vp9.c:198
av_seek_frame
int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Seek to the keyframe at timestamp.
Definition: seek.c:639
AVFormatContext::flags
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1481
format
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample format(the sample packing is implied by the sample format) and sample rate. The lists are not just lists
AVFormatContext::nb_programs
unsigned int nb_programs
Definition: avformat.h:1530
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:554
AVFormatContext::iformat
const struct AVInputFormat * iformat
The input container format.
Definition: avformat.h:1375
AVFormatContext::chapters
AVChapter ** chapters
Definition: avformat.h:1581
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:454
AVIndexEntry::size
int size
Definition: avformat.h:711
AVProbeData::filename
const char * filename
Definition: avformat.h:453
AVOpenCallback
int(* AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options)
Definition: avformat.h:1336
av_match_ext
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:41
AVIndexEntry::timestamp
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:702
AVOutputFormat::audio_codec
enum AVCodecID audio_codec
default audio codec
Definition: avformat.h:521
AVFormatContext::output_ts_offset
int64_t output_ts_offset
Output timestamp offset, in microseconds.
Definition: avformat.h:1879
AVInputFormat::mime_type
const char * mime_type
Comma-separated list of mime types.
Definition: avformat.h:586
AVStreamGroup::index
unsigned int index
Group index in AVFormatContext.
Definition: avformat.h:1199
av_read_play
int av_read_play(AVFormatContext *s)
Start playing a network-based stream (e.g.
Definition: demux_utils.c:202
ctx
AVFormatContext * ctx
Definition: movenc.c:48
av_guess_sample_aspect_ratio
AVRational av_guess_sample_aspect_ratio(AVFormatContext *format, AVStream *stream, struct AVFrame *frame)
Guess the sample aspect ratio of a frame, based on both the stream and the frame aspect ratio.
Definition: avformat.c:717
avformat_flush
int avformat_flush(AVFormatContext *s)
Discard all internally buffered data.
Definition: seek.c:757
AVOutputFormat::codec_tag
const struct AVCodecTag *const * codec_tag
List of supported codec_id-codec_tag pairs, ordered by "better choice first".
Definition: avformat.h:536
version_major.h
AVIndexEntry::min_distance
int min_distance
Minimum distance between this and the previous keyframe, used to avoid unneeded searching.
Definition: avformat.h:712
codec_id
enum AVCodecID codec_id
Definition: vaapi_decode.c:389
AVProgram::start_time
int64_t start_time
Definition: avformat.h:1307
AVFormatContext::opaque
void * opaque
User data.
Definition: avformat.h:1868
AVFormatContext::data_codec
const struct AVCodec * data_codec
Forced data codec.
Definition: avformat.h:1855
AVFormatContext::probe_score
int probe_score
format probing score.
Definition: avformat.h:1788
avformat_write_header
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:472
frame
static AVFrame * frame
Definition: demux_decode.c:54
AVFormatContext::max_analyze_duration
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:1525
AVFormatContext::correct_ts_overflow
unsigned int correct_ts_overflow
Correct single timestamp overflows.
Definition: avformat.h:1765
av_probe_input_format2
const AVInputFormat * av_probe_input_format2(const AVProbeData *pd, int is_opened, int *score_max)
Guess the file format.
Definition: format.c:233
AVFormatContext
Format I/O context.
Definition: avformat.h:1363
AVFormatContext::audio_codec_id
enum AVCodecID audio_codec_id
Forced audio codec_id.
Definition: avformat.h:1543
av_probe_input_format
const AVInputFormat * av_probe_input_format(const AVProbeData *pd, int is_opened)
Guess the file format.
Definition: format.c:245
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:864
AVInputFormat::codec_tag
const struct AVCodecTag *const * codec_tag
Definition: avformat.h:577
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
av_write_uncoded_frame
int av_write_uncoded_frame(AVFormatContext *s, int stream_index, struct AVFrame *frame)
Write an uncoded frame to an output media file.
Definition: mux.c:1471
AVStream::time_base
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition: avformat.h:880
AVFormatContext::max_streams
int max_streams
The maximum number of streams.
Definition: avformat.h:1947
AVFormatContext::fps_probe_size
int fps_probe_size
The number of frames used for determining the framerate in avformat_find_stream_info().
Definition: avformat.h:1611
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVFMT_DURATION_FROM_STREAM
@ AVFMT_DURATION_FROM_STREAM
Duration estimated from a stream with a known duration.
Definition: avformat.h:1345
AVFormatContext::protocol_whitelist
char * protocol_whitelist
',' separated list of allowed protocols.
Definition: avformat.h:1900
AVOutputFormat::long_name
const char * long_name
Descriptive name for the format, meant to be more human-readable than name.
Definition: avformat.h:517
AVSTREAM_PARSE_NONE
@ AVSTREAM_PARSE_NONE
Definition: avformat.h:690
AVInputFormat::read_probe
int(* read_probe)(const AVProbeData *)
Tell if a given file has a chance of being parsed as this format.
Definition: avformat.h:615
AVIndexEntry::flags
int flags
Definition: avformat.h:710
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1405
AVDurationEstimationMethod
AVDurationEstimationMethod
The duration of a video can be estimated through various ways, and this enum can be used to know how ...
Definition: avformat.h:1343
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:452
AVProgram::stream_index
unsigned int * stream_index
Definition: avformat.h:1291
AVStream::metadata
AVDictionary * metadata
Definition: avformat.h:921
AVFormatContext::skip_estimate_duration_from_pts
int skip_estimate_duration_from_pts
Skip duration calcuation in estimate_timings_from_pts.
Definition: avformat.h:1954
AVOutputFormat::priv_class
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:539
av_write_frame
int av_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file.
Definition: mux.c:1218
index
int index
Definition: gxfenc.c:89
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVFormatContext::audio_codec
const struct AVCodec * audio_codec
Forced audio codec.
Definition: avformat.h:1839
AVStream::nb_frames
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:902
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:49
avformat_stream_group_add_stream
int avformat_stream_group_add_stream(AVStreamGroup *stg, AVStream *st)
Add an already allocated stream to a stream group.
Definition: options.c:504
AVFormatContext::nb_streams
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1419
AVFormatContext::metadata_header_padding
int metadata_header_padding
Number of bytes to be written as padding in a metadata header.
Definition: avformat.h:1862
AVOutputFormat::flags
int flags
can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS,...
Definition: avformat.h:530
AV_STREAM_GROUP_PARAMS_TILE_GRID
@ AV_STREAM_GROUP_PARAMS_TILE_GRID
Definition: avformat.h:1182
AVInputFormat::flags_internal
int flags_internal
Internal flags.
Definition: avformat.h:608
options
const OptionDef options[]
avformat_find_stream_info
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
Definition: demux.c:2532
f
f
Definition: af_crystalizer.c:121
AVIOContext
Bytestream IO Context.
Definition: avio.h:166
AVProgram::pts_wrap_reference
int64_t pts_wrap_reference
reference dts for wrap detection
Definition: avformat.h:1310
AVMediaType
AVMediaType
Definition: avutil.h:199
avformat_match_stream_specifier
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: avformat.c:671
av_find_best_stream
int av_find_best_stream(AVFormatContext *ic, enum AVMediaType type, int wanted_stream_nb, int related_stream, const struct AVCodec **decoder_ret, int flags)
Find the "best" stream in the file.
avformat_alloc_context
AVFormatContext * avformat_alloc_context(void)
Allocate an AVFormatContext.
Definition: options.c:167
av_codec_get_tag
unsigned int av_codec_get_tag(const struct AVCodecTag *const *tags, enum AVCodecID id)
Get the codec tag for the given codec id id.
AVProgram::end_time
int64_t end_time
Definition: avformat.h:1308
AVFormatContext::url
char * url
input or output URL.
Definition: avformat.h:1446
size
int size
Definition: twinvq_data.h:10344
avio.h
copy_tb
int copy_tb
Definition: ffmpeg_opt.c:75
avformat_seek_file
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: seek.c:662
AVStreamGroup::iamf_audio_element
struct AVIAMFAudioElement * iamf_audio_element
Definition: avformat.h:1221
AVStream::event_flags
int event_flags
Flags indicating events happening on the stream, a combination of AVSTREAM_EVENT_FLAG_*.
Definition: avformat.h:984
av_stream_get_codec_timebase
AVRational av_stream_get_codec_timebase(const AVStream *st)
Get the internal codec timebase from a stream.
Definition: avformat.c:838
AVProgram::pts_wrap_behavior
int pts_wrap_behavior
behavior on wrap detection
Definition: avformat.h:1311
AVTimebaseSource
AVTimebaseSource
Definition: avformat.h:3146
av_demuxer_iterate
const AVInputFormat * av_demuxer_iterate(void **opaque)
Iterate over all registered demuxers.
Definition: allformats.c:601
AVProgram::program_num
int program_num
Definition: avformat.h:1295
AVStream::sample_aspect_ratio
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:919
frame.h
AVFormatContext::keylen
int keylen
Definition: avformat.h:1528
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:104
AVIAMFAudioElement
Information on how to combine one or more audio streams, as defined in section 3.6 of IAMF.
Definition: iamf.h:347
AVStreamGroupTileGrid::nb_tiles
unsigned int nb_tiles
Amount of tiles in the grid.
Definition: avformat.h:1088
av_sdp_create
int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size)
Generate an SDP for an RTP session.
Definition: sdp.c:911
av_format_inject_global_side_data
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: demux_utils.c:83
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
av_probe_input_buffer
int av_probe_input_buffer(AVIOContext *pb, const 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:343
AV_STREAM_GROUP_PARAMS_IAMF_AUDIO_ELEMENT
@ AV_STREAM_GROUP_PARAMS_IAMF_AUDIO_ELEMENT
Definition: avformat.h:1180
AVStreamGroup::streams
AVStream ** streams
A list of streams in the group.
Definition: avformat.h:1254
AVStreamGroup::iamf_mix_presentation
struct AVIAMFMixPresentation * iamf_mix_presentation
Definition: avformat.h:1222
AVOutputFormat::mime_type
const char * mime_type
Definition: avformat.h:518
AVFormatContext::skip_initial_bytes
int64_t skip_initial_bytes
Skip initial bytes when opening stream.
Definition: avformat.h:1758
av_warn_unused_result
#define av_warn_unused_result
Definition: attributes.h:64
AVFormatContext::error_recognition
int error_recognition
Error recognition; higher values will detect more errors but may misdetect some more or less valid pa...
Definition: avformat.h:1618
av_write_trailer
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
Definition: mux.c:1286
av_disposition_from_string
int av_disposition_from_string(const char *disp)
Definition: options.c:525
AVStreamGroupTileGrid::width
int width
Width of the final image for presentation.
Definition: avformat.h:1165
AV_STREAM_GROUP_PARAMS_NONE
@ AV_STREAM_GROUP_PARAMS_NONE
Definition: avformat.h:1179
log.h
AVOutputFormat
Definition: avformat.h:510
AVChapter::id
int64_t id
unique ID to identify the chapter
Definition: avformat.h:1323
packet.h
AVFormatContext::subtitle_codec
const struct AVCodec * subtitle_codec
Forced subtitle codec.
Definition: avformat.h:1847
AVInputFormat::priv_data_size
int priv_data_size
Size of private data so that it can be allocated in the wrapper.
Definition: avformat.h:603
avformat_get_mov_audio_tags
const struct AVCodecTag * avformat_get_mov_audio_tags(void)
Definition: isom_tags.c:362
AVProgram::metadata
AVDictionary * metadata
Definition: avformat.h:1293
AVIAMFMixPresentation
Information on how to render and mix one or more AVIAMFAudioElement to generate the final audio outpu...
Definition: iamf.h:600
avformat_index_get_entry
const AVIndexEntry * avformat_index_get_entry(AVStream *st, int idx)
Get the AVIndexEntry corresponding to the given index.
Definition: seek.c:255
AVStream::av_class
const AVClass * av_class
A class for AVOptions.
Definition: avformat.h:845
av_get_output_timestamp
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:1332
AVFormatContext::codec_whitelist
char * codec_whitelist
',' separated list of allowed decoders.
Definition: avformat.h:1807
AVFormatContext::avoid_negative_ts
int avoid_negative_ts
Avoid negative timestamps during muxing.
Definition: avformat.h:1694
av_url_split
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:358
av_find_default_stream_index
int av_find_default_stream_index(AVFormatContext *s)
Definition: avformat.c:397
AVFormatContext::max_delay
int max_delay
Definition: avformat.h:1475
AVFormatContext::io_repositioned
int io_repositioned
IO repositioned flag.
Definition: avformat.h:1823
AVProgram
New fields can be added to the end with minor version bumps.
Definition: avformat.h:1287
av_read_pause
int av_read_pause(AVFormatContext *s)
Pause a network-based stream (e.g.
Definition: demux_utils.c:211
AVInputFormat::read_packet
int(* read_packet)(struct AVFormatContext *, AVPacket *pkt)
Read one packet and put it in 'pkt'.
Definition: avformat.h:632
int_cb
const AVIOInterruptCB int_cb
Definition: ffmpeg.c:324
av_get_packet
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:103
AVStreamGroupTileGrid::horizontal
int horizontal
Offset in pixels from the left edge of the canvas where the tile should be placed.
Definition: avformat.h:1124
AVCodecParserContext
Definition: avcodec.h:2781
AVInputFormat::get_device_list
int(* get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list)
Returns device list with it properties.
Definition: avformat.h:682
AVInputFormat::read_seek
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:648
version.h
AVStreamGroup::params
union AVStreamGroup::@295 params
Group type-specific parameters.
AVStream::disposition
int disposition
Stream disposition - a combination of AV_DISPOSITION_* flags.
Definition: avformat.h:910
tag
uint32_t tag
Definition: movenc.c:1786
AVStream::id
int id
Format-specific stream ID.
Definition: avformat.h:853
AVStream
Stream structure.
Definition: avformat.h:841
AVFormatContext::ts_id
int ts_id
Transport stream id.
Definition: avformat.h:1704
av_guess_frame_rate
AVRational av_guess_frame_rate(AVFormatContext *ctx, AVStream *stream, struct AVFrame *frame)
Guess the frame rate, based on both the container and codec information.
Definition: avformat.c:740
av_hex_dump_log
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:86
AVFormatContext::oformat
const struct AVOutputFormat * oformat
The output container format.
Definition: avformat.h:1382
AVStreamGroup::metadata
AVDictionary * metadata
Metadata that applies to the whole group.
Definition: avformat.h:1234
AVDeviceInfoList
List of devices.
Definition: avdevice.h:343
av_append_packet
int av_append_packet(AVIOContext *s, AVPacket *pkt, int size)
Read data and append it to the current content of the AVPacket.
Definition: utils.c:119
AVSTREAM_PARSE_HEADERS
@ AVSTREAM_PARSE_HEADERS
Only parse headers, do not repack.
Definition: avformat.h:692
AVFormatContext::av_class
const AVClass * av_class
A class for logging and AVOptions.
Definition: avformat.h:1368
pos
unsigned int pos
Definition: spdifenc.c:413
dict.h
av_guess_codec
enum AVCodecID av_guess_codec(const 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:115
avformat_network_deinit
int avformat_network_deinit(void)
Undo the initialization done by avformat_network_init.
Definition: utils.c:570
AVStreamGroup
Definition: avformat.h:1188
AVFormatContext::debug
int debug
Flags to enable debugging.
Definition: avformat.h:1634
AVFormatContext::data_codec_id
enum AVCodecID data_codec_id
Forced Data codec_id.
Definition: avformat.h:1893
AVStream::index
int index
stream index in AVFormatContext
Definition: avformat.h:847
AVInputFormat::read_seek2
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:676
av_muxer_iterate
const AVOutputFormat * av_muxer_iterate(void **opaque)
Iterate over all registered muxers.
Definition: allformats.c:580
avformat_transfer_internal_stream_timing_info
int avformat_transfer_internal_stream_timing_info(const AVOutputFormat *ofmt, AVStream *ost, const AVStream *ist, enum AVTimebaseSource copy_tb)
Transfer internal timing information from one stream to another.
Definition: avformat.c:763
format_name
static int format_name(const char *buf, char **s, int index, const char *varname)
Definition: hlsenc.c:1948
AVStreamGroup::nb_streams
unsigned int nb_streams
Number of elements in AVStreamGroup.streams.
Definition: avformat.h:1241
AVInputFormat::read_close
int(* read_close)(struct AVFormatContext *)
Close the stream.
Definition: avformat.h:638
AVFormatContext::seek2any
int seek2any
Force seeking to any (also non key) frames.
Definition: avformat.h:1772
AVInputFormat::flags
int flags
Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS, AVFMT_NOTIMESTAMPS,...
Definition: avformat.h:568
AVInputFormat::read_pause
int(* read_pause)(struct AVFormatContext *)
Pause playing - only meaningful if using a network-based format (RTSP).
Definition: avformat.h:668
defs.h
avformat_free_context
void avformat_free_context(AVFormatContext *s)
Free an AVFormatContext and all its streams.
Definition: avformat.c:141
AVOutputFormat::video_codec
enum AVCodecID video_codec
default video codec
Definition: avformat.h:522
AVStream::r_frame_rate
AVRational r_frame_rate
Real base framerate of the stream.
Definition: avformat.h:1007
AVFormatContext::io_open
int(* io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags, AVDictionary **options)
A callback for opening new IO streams.
Definition: avformat.h:1922
AVIndexEntry::pos
int64_t pos
Definition: avformat.h:701
AVSTREAM_PARSE_FULL_RAW
@ AVSTREAM_PARSE_FULL_RAW
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:695
AVPacketSideDataType
AVPacketSideDataType
Definition: packet.h:41
av_find_input_format
const AVInputFormat * av_find_input_format(const char *short_name)
Find AVInputFormat based on the short name of the input format.
Definition: format.c:144
AVFormatContext::duration
int64_t duration
Duration of the stream, in AV_TIME_BASE fractional seconds.
Definition: avformat.h:1465
avformat_license
const char * avformat_license(void)
Return the libavformat license.
Definition: version.c:41
AVFormatContext::packet_size
unsigned int packet_size
Definition: avformat.h:1474
av_guess_format
const 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:79
AVStreamGroup::type
enum AVStreamGroupParamsType type
Group type.
Definition: avformat.h:1215
AVFormatContext::start_time_realtime
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:1604
avformat_configuration
const char * avformat_configuration(void)
Return the libavformat build-time configuration.
Definition: version.c:36
avformat_stream_group_create
AVStreamGroup * avformat_stream_group_create(AVFormatContext *s, enum AVStreamGroupParamsType type, AVDictionary **options)
Add a new empty stream group to a media file.
Definition: options.c:431
AVFormatContext::nb_stream_groups
unsigned int nb_stream_groups
Number of elements in AVFormatContext.stream_groups.
Definition: avformat.h:1981
AVStreamGroupTileGrid::height
int height
Height of the final image for presentation.
Definition: avformat.h:1175
AVFormatContext::max_probe_packets
int max_probe_packets
Maximum number of packets that can be probed.
Definition: avformat.h:1961
codec_par.h
av_interleaved_write_uncoded_frame
int av_interleaved_write_uncoded_frame(AVFormatContext *s, int stream_index, struct AVFrame *frame)
Write an uncoded frame to an output media file.
Definition: mux.c:1477
AVPacket
This structure stores compressed data.
Definition: packet.h:499
AVFormatContext::use_wallclock_as_timestamps
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:1736
av_interleaved_write_frame
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file ensuring correct interleaving.
Definition: mux.c:1271
AVFormatContext::io_close2
int(* io_close2)(struct AVFormatContext *s, AVIOContext *pb)
A callback for closing the streams opened with AVFormatContext.io_open().
Definition: avformat.h:1974
distance
static float distance(float x, float y, int band)
Definition: nellymoserenc.c:230
AVSTREAM_PARSE_FULL
@ AVSTREAM_PARSE_FULL
full parsing and repack
Definition: avformat.h:691
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
AVInputFormat::read_timestamp
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:655
AVFormatContext::start_time
int64_t start_time
Position of the first frame of the component, in AV_TIME_BASE fractional seconds.
Definition: avformat.h:1455
av_stream_get_parser
struct AVCodecParserContext * av_stream_get_parser(const AVStream *s)
Definition: demux_utils.c:32
av_pkt_dump_log2
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:120
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:890
av_stream_get_class
const AVClass * av_stream_get_class(void)
Get the AVClass for AVStream.
Definition: options.c:254
AVSTREAM_PARSE_TIMESTAMPS
@ AVSTREAM_PARSE_TIMESTAMPS
full parsing and interpolation of timestamps for frames not starting on a packet boundary
Definition: avformat.h:693
AVFormatContext::avio_flags
int avio_flags
avio flags, used to force AVIO_FLAG_DIRECT.
Definition: avformat.h:1743
AVDiscard
AVDiscard
Definition: defs.h:210
AVStreamGroupTileGrid::idx
unsigned int idx
Index of the stream in the group this tile references.
Definition: avformat.h:1119
avformat_alloc_output_context2
int avformat_alloc_output_context2(AVFormatContext **ctx, const AVOutputFormat *oformat, const char *format_name, const char *filename)
Allocate an AVFormatContext for an output format.
Definition: mux.c:93
AVStream::pts_wrap_bits
int pts_wrap_bits
Number of bits in timestamps.
Definition: avformat.h:1016
AVInputFormat::read_header
int(* read_header)(struct AVFormatContext *)
Read the format header and initialize the AVFormatContext structure.
Definition: avformat.h:622
AVChapter::time_base
AVRational time_base
time base in which the start/end timestamps are specified
Definition: avformat.h:1324
int
int
Definition: ffmpeg_filter.c:424
AVStreamGroup::priv_data
void * priv_data
Definition: avformat.h:1194
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1391
AVProgram::pcr_pid
int pcr_pid
Definition: avformat.h:1297
AVFormatContext::key
const uint8_t * key
Definition: avformat.h:1527
AVInputFormat::priv_class
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:579
AVStreamGroupTileGrid::background
uint8_t background[4]
The pixel value per channel in RGBA format used if no pixel of any tile is located at a particular pi...
Definition: avformat.h:1139
AVFormatContext::max_chunk_size
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:1728
av_index_search_timestamp
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: seek.c:243
AVInputFormat::read_play
int(* read_play)(struct AVFormatContext *)
Start/resume playing - only meaningful if using a network-based format (RTSP).
Definition: avformat.h:662
av_program_add_stream_index
void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx)
AVFormatContext::subtitle_codec_id
enum AVCodecID subtitle_codec_id
Forced subtitle codec_id.
Definition: avformat.h:1549
av_hex_dump
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:81