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avformat.h
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1 /*
2  * copyright (c) 2001 Fabrice Bellard
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef AVFORMAT_AVFORMAT_H
22 #define AVFORMAT_AVFORMAT_H
23 
24 /**
25  * @file
26  * @ingroup libavf
27  * Main libavformat public API header
28  */
29 
30 /**
31  * @defgroup libavf 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). Before using lavf, you need to call
40  * av_register_all() to register all compiled muxers, demuxers and protocols.
41  * Unless you are absolutely sure you won't use libavformat's network
42  * capabilities, you should also call avformat_network_init().
43  *
44  * A supported input format is described by an AVInputFormat struct, conversely
45  * an output format is described by AVOutputFormat. You can iterate over all
46  * registered input/output formats using the av_iformat_next() /
47  * av_oformat_next() functions. The protocols layer is not part of the public
48  * API, so you can only get the names of supported protocols with the
49  * avio_enum_protocols() function.
50  *
51  * Main lavf structure used for both muxing and demuxing is AVFormatContext,
52  * which exports all information about the file being read or written. As with
53  * most Libavformat structures, its size is not part of public ABI, so it cannot be
54  * allocated on stack or directly with av_malloc(). To create an
55  * AVFormatContext, use avformat_alloc_context() (some functions, like
56  * avformat_open_input() might do that for you).
57  *
58  * Most importantly an AVFormatContext contains:
59  * @li the @ref AVFormatContext.iformat "input" or @ref AVFormatContext.oformat
60  * "output" format. It is either autodetected or set by user for input;
61  * always set by user for output.
62  * @li an @ref AVFormatContext.streams "array" of AVStreams, which describe all
63  * elementary streams stored in the file. AVStreams are typically referred to
64  * using their index in this array.
65  * @li an @ref AVFormatContext.pb "I/O context". It is either opened by lavf or
66  * set by user for input, always set by user for output (unless you are dealing
67  * with an AVFMT_NOFILE format).
68  *
69  * @section lavf_options Passing options to (de)muxers
70  * It is possible to configure lavf muxers and demuxers using the @ref avoptions
71  * mechanism. Generic (format-independent) libavformat options are provided by
72  * AVFormatContext, they can be examined from a user program by calling
73  * av_opt_next() / av_opt_find() on an allocated AVFormatContext (or its AVClass
74  * from avformat_get_class()). Private (format-specific) options are provided by
75  * AVFormatContext.priv_data if and only if AVInputFormat.priv_class /
76  * AVOutputFormat.priv_class of the corresponding format struct is non-NULL.
77  * Further options may be provided by the @ref AVFormatContext.pb "I/O context",
78  * if its AVClass is non-NULL, and the protocols layer. See the discussion on
79  * nesting in @ref avoptions documentation to learn how to access those.
80  *
81  * @section urls
82  * URL strings in libavformat are made of a scheme/protocol, a ':', and a
83  * scheme specific string. URLs without a scheme and ':' used for local files
84  * are supported but deprecated. "file:" should be used for local files.
85  *
86  * It is important that the scheme string is not taken from untrusted
87  * sources without checks.
88  *
89  * Note that some schemes/protocols are quite powerful, allowing access to
90  * both local and remote files, parts of them, concatenations of them, local
91  * audio and video devices and so on.
92  *
93  * @{
94  *
95  * @defgroup lavf_decoding Demuxing
96  * @{
97  * Demuxers read a media file and split it into chunks of data (@em packets). A
98  * @ref AVPacket "packet" contains one or more encoded frames which belongs to a
99  * single elementary stream. In the lavf API this process is represented by the
100  * avformat_open_input() function for opening a file, av_read_frame() for
101  * reading a single packet and finally avformat_close_input(), which does the
102  * cleanup.
103  *
104  * @section lavf_decoding_open Opening a media file
105  * The minimum information required to open a file is its URL, which
106  * is passed to avformat_open_input(), as in the following code:
107  * @code
108  * const char *url = "file:in.mp3";
109  * AVFormatContext *s = NULL;
110  * int ret = avformat_open_input(&s, url, NULL, NULL);
111  * if (ret < 0)
112  * abort();
113  * @endcode
114  * The above code attempts to allocate an AVFormatContext, open the
115  * specified file (autodetecting the format) and read the header, exporting the
116  * information stored there into s. Some formats do not have a header or do not
117  * store enough information there, so it is recommended that you call the
118  * avformat_find_stream_info() function which tries to read and decode a few
119  * frames to find missing information.
120  *
121  * In some cases you might want to preallocate an AVFormatContext yourself with
122  * avformat_alloc_context() and do some tweaking on it before passing it to
123  * avformat_open_input(). One such case is when you want to use custom functions
124  * for reading input data instead of lavf internal I/O layer.
125  * To do that, create your own AVIOContext with avio_alloc_context(), passing
126  * your reading callbacks to it. Then set the @em pb field of your
127  * AVFormatContext to newly created AVIOContext.
128  *
129  * Since the format of the opened file is in general not known until after
130  * avformat_open_input() has returned, it is not possible to set demuxer private
131  * options on a preallocated context. Instead, the options should be passed to
132  * avformat_open_input() wrapped in an AVDictionary:
133  * @code
134  * AVDictionary *options = NULL;
135  * av_dict_set(&options, "video_size", "640x480", 0);
136  * av_dict_set(&options, "pixel_format", "rgb24", 0);
137  *
138  * if (avformat_open_input(&s, url, NULL, &options) < 0)
139  * abort();
140  * av_dict_free(&options);
141  * @endcode
142  * This code passes the private options 'video_size' and 'pixel_format' to the
143  * demuxer. They would be necessary for e.g. the rawvideo demuxer, since it
144  * cannot know how to interpret raw video data otherwise. If the format turns
145  * out to be something different than raw video, those options will not be
146  * recognized by the demuxer and therefore will not be applied. Such unrecognized
147  * options are then returned in the options dictionary (recognized options are
148  * consumed). The calling program can handle such unrecognized options as it
149  * wishes, e.g.
150  * @code
151  * AVDictionaryEntry *e;
152  * if (e = av_dict_get(options, "", NULL, AV_DICT_IGNORE_SUFFIX)) {
153  * fprintf(stderr, "Option %s not recognized by the demuxer.\n", e->key);
154  * abort();
155  * }
156  * @endcode
157  *
158  * After you have finished reading the file, you must close it with
159  * avformat_close_input(). It will free everything associated with the file.
160  *
161  * @section lavf_decoding_read Reading from an opened file
162  * Reading data from an opened AVFormatContext is done by repeatedly calling
163  * av_read_frame() on it. Each call, if successful, will return an AVPacket
164  * containing encoded data for one AVStream, identified by
165  * AVPacket.stream_index. This packet may be passed straight into the libavcodec
166  * decoding functions avcodec_send_packet() or avcodec_decode_subtitle2() if the
167  * caller wishes to decode the data.
168  *
169  * AVPacket.pts, AVPacket.dts and AVPacket.duration timing information will be
170  * set if known. They may also be unset (i.e. AV_NOPTS_VALUE for
171  * pts/dts, 0 for duration) if the stream does not provide them. The timing
172  * information will be in AVStream.time_base units, i.e. it has to be
173  * multiplied by the timebase to convert them to seconds.
174  *
175  * If AVPacket.buf is set on the returned packet, then the packet is
176  * allocated dynamically and the user may keep it indefinitely.
177  * Otherwise, if AVPacket.buf is NULL, the packet data is backed by a
178  * static storage somewhere inside the demuxer and the packet is only valid
179  * until the next av_read_frame() call or closing the file. If the caller
180  * requires a longer lifetime, av_dup_packet() will make an av_malloc()ed copy
181  * of it.
182  * In both cases, the packet must be freed with av_packet_unref() when it is no
183  * longer needed.
184  *
185  * @section lavf_decoding_seek Seeking
186  * @}
187  *
188  * @defgroup lavf_encoding Muxing
189  * @{
190  * Muxers take encoded data in the form of @ref AVPacket "AVPackets" and write
191  * it into files or other output bytestreams in the specified container format.
192  *
193  * The main API functions for muxing are avformat_write_header() for writing the
194  * file header, av_write_frame() / av_interleaved_write_frame() for writing the
195  * packets and av_write_trailer() for finalizing the file.
196  *
197  * At the beginning of the muxing process, the caller must first call
198  * avformat_alloc_context() to create a muxing context. The caller then sets up
199  * the muxer by filling the various fields in this context:
200  *
201  * - The @ref AVFormatContext.oformat "oformat" field must be set to select the
202  * muxer that will be used.
203  * - Unless the format is of the AVFMT_NOFILE type, the @ref AVFormatContext.pb
204  * "pb" field must be set to an opened IO context, either returned from
205  * avio_open2() or a custom one.
206  * - Unless the format is of the AVFMT_NOSTREAMS type, at least one stream must
207  * be created with the avformat_new_stream() function. The caller should fill
208  * the @ref AVStream.codecpar "stream codec parameters" information, such as the
209  * codec @ref AVCodecParameters.codec_type "type", @ref AVCodecParameters.codec_id
210  * "id" and other parameters (e.g. width / height, the pixel or sample format,
211  * etc.) as known. The @ref AVStream.time_base "stream timebase" should
212  * be set to the timebase that the caller desires to use for this stream (note
213  * that the timebase actually used by the muxer can be different, as will be
214  * described later).
215  * - It is advised to manually initialize only the relevant fields in
216  * AVCodecParameters, rather than using @ref avcodec_parameters_copy() during
217  * remuxing: there is no guarantee that the codec context values remain valid
218  * for both input and output format contexts.
219  * - The caller may fill in additional information, such as @ref
220  * AVFormatContext.metadata "global" or @ref AVStream.metadata "per-stream"
221  * metadata, @ref AVFormatContext.chapters "chapters", @ref
222  * AVFormatContext.programs "programs", etc. as described in the
223  * AVFormatContext documentation. Whether such information will actually be
224  * stored in the output depends on what the container format and the muxer
225  * support.
226  *
227  * When the muxing context is fully set up, the caller must call
228  * avformat_write_header() to initialize the muxer internals and write the file
229  * header. Whether anything actually is written to the IO context at this step
230  * depends on the muxer, but this function must always be called. Any muxer
231  * private options must be passed in the options parameter to this function.
232  *
233  * The data is then sent to the muxer by repeatedly calling av_write_frame() or
234  * av_interleaved_write_frame() (consult those functions' documentation for
235  * discussion on the difference between them; only one of them may be used with
236  * a single muxing context, they should not be mixed). Do note that the timing
237  * information on the packets sent to the muxer must be in the corresponding
238  * AVStream's timebase. That timebase is set by the muxer (in the
239  * avformat_write_header() step) and may be different from the timebase
240  * requested by the caller.
241  *
242  * Once all the data has been written, the caller must call av_write_trailer()
243  * to flush any buffered packets and finalize the output file, then close the IO
244  * context (if any) and finally free the muxing context with
245  * avformat_free_context().
246  * @}
247  *
248  * @defgroup lavf_io I/O Read/Write
249  * @{
250  * @section lavf_io_dirlist Directory listing
251  * The directory listing API makes it possible to list files on remote servers.
252  *
253  * Some of possible use cases:
254  * - an "open file" dialog to choose files from a remote location,
255  * - a recursive media finder providing a player with an ability to play all
256  * files from a given directory.
257  *
258  * @subsection lavf_io_dirlist_open Opening a directory
259  * At first, a directory needs to be opened by calling avio_open_dir()
260  * supplied with a URL and, optionally, ::AVDictionary containing
261  * protocol-specific parameters. The function returns zero or positive
262  * integer and allocates AVIODirContext on success.
263  *
264  * @code
265  * AVIODirContext *ctx = NULL;
266  * if (avio_open_dir(&ctx, "smb://example.com/some_dir", NULL) < 0) {
267  * fprintf(stderr, "Cannot open directory.\n");
268  * abort();
269  * }
270  * @endcode
271  *
272  * This code tries to open a sample directory using smb protocol without
273  * any additional parameters.
274  *
275  * @subsection lavf_io_dirlist_read Reading entries
276  * Each directory's entry (i.e. file, another directory, anything else
277  * within ::AVIODirEntryType) is represented by AVIODirEntry.
278  * Reading consecutive entries from an opened AVIODirContext is done by
279  * repeatedly calling avio_read_dir() on it. Each call returns zero or
280  * positive integer if successful. Reading can be stopped right after the
281  * NULL entry has been read -- it means there are no entries left to be
282  * read. The following code reads all entries from a directory associated
283  * with ctx and prints their names to standard output.
284  * @code
285  * AVIODirEntry *entry = NULL;
286  * for (;;) {
287  * if (avio_read_dir(ctx, &entry) < 0) {
288  * fprintf(stderr, "Cannot list directory.\n");
289  * abort();
290  * }
291  * if (!entry)
292  * break;
293  * printf("%s\n", entry->name);
294  * avio_free_directory_entry(&entry);
295  * }
296  * @endcode
297  * @}
298  *
299  * @defgroup lavf_codec Demuxers
300  * @{
301  * @defgroup lavf_codec_native Native Demuxers
302  * @{
303  * @}
304  * @defgroup lavf_codec_wrappers External library wrappers
305  * @{
306  * @}
307  * @}
308  * @defgroup lavf_protos I/O Protocols
309  * @{
310  * @}
311  * @defgroup lavf_internal Internal
312  * @{
313  * @}
314  * @}
315  */
316 
317 #include <time.h>
318 #include <stdio.h> /* FILE */
319 #include "libavcodec/avcodec.h"
320 #include "libavutil/dict.h"
321 #include "libavutil/log.h"
322 
323 #include "avio.h"
324 #include "libavformat/version.h"
325 
326 struct AVFormatContext;
327 
328 struct AVDeviceInfoList;
330 
331 /**
332  * @defgroup metadata_api Public Metadata API
333  * @{
334  * @ingroup libavf
335  * The metadata API allows libavformat to export metadata tags to a client
336  * application when demuxing. Conversely it allows a client application to
337  * set metadata when muxing.
338  *
339  * Metadata is exported or set as pairs of key/value strings in the 'metadata'
340  * fields of the AVFormatContext, AVStream, AVChapter and AVProgram structs
341  * using the @ref lavu_dict "AVDictionary" API. Like all strings in FFmpeg,
342  * metadata is assumed to be UTF-8 encoded Unicode. Note that metadata
343  * exported by demuxers isn't checked to be valid UTF-8 in most cases.
344  *
345  * Important concepts to keep in mind:
346  * - Keys are unique; there can never be 2 tags with the same key. This is
347  * also meant semantically, i.e., a demuxer should not knowingly produce
348  * several keys that are literally different but semantically identical.
349  * E.g., key=Author5, key=Author6. In this example, all authors must be
350  * placed in the same tag.
351  * - Metadata is flat, not hierarchical; there are no subtags. If you
352  * want to store, e.g., the email address of the child of producer Alice
353  * and actor Bob, that could have key=alice_and_bobs_childs_email_address.
354  * - Several modifiers can be applied to the tag name. This is done by
355  * appending a dash character ('-') and the modifier name in the order
356  * they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng.
357  * - language -- a tag whose value is localized for a particular language
358  * is appended with the ISO 639-2/B 3-letter language code.
359  * For example: Author-ger=Michael, Author-eng=Mike
360  * The original/default language is in the unqualified "Author" tag.
361  * A demuxer should set a default if it sets any translated tag.
362  * - sorting -- a modified version of a tag that should be used for
363  * sorting will have '-sort' appended. E.g. artist="The Beatles",
364  * artist-sort="Beatles, The".
365  * - Some protocols and demuxers support metadata updates. After a successful
366  * call to av_read_packet(), AVFormatContext.event_flags or AVStream.event_flags
367  * will be updated to indicate if metadata changed. In order to detect metadata
368  * changes on a stream, you need to loop through all streams in the AVFormatContext
369  * and check their individual event_flags.
370  *
371  * - Demuxers attempt to export metadata in a generic format, however tags
372  * with no generic equivalents are left as they are stored in the container.
373  * Follows a list of generic tag names:
374  *
375  @verbatim
376  album -- name of the set this work belongs to
377  album_artist -- main creator of the set/album, if different from artist.
378  e.g. "Various Artists" for compilation albums.
379  artist -- main creator of the work
380  comment -- any additional description of the file.
381  composer -- who composed the work, if different from artist.
382  copyright -- name of copyright holder.
383  creation_time-- date when the file was created, preferably in ISO 8601.
384  date -- date when the work was created, preferably in ISO 8601.
385  disc -- number of a subset, e.g. disc in a multi-disc collection.
386  encoder -- name/settings of the software/hardware that produced the file.
387  encoded_by -- person/group who created the file.
388  filename -- original name of the file.
389  genre -- <self-evident>.
390  language -- main language in which the work is performed, preferably
391  in ISO 639-2 format. Multiple languages can be specified by
392  separating them with commas.
393  performer -- artist who performed the work, if different from artist.
394  E.g for "Also sprach Zarathustra", artist would be "Richard
395  Strauss" and performer "London Philharmonic Orchestra".
396  publisher -- name of the label/publisher.
397  service_name -- name of the service in broadcasting (channel name).
398  service_provider -- name of the service provider in broadcasting.
399  title -- name of the work.
400  track -- number of this work in the set, can be in form current/total.
401  variant_bitrate -- the total bitrate of the bitrate variant that the current stream is part of
402  @endverbatim
403  *
404  * Look in the examples section for an application example how to use the Metadata API.
405  *
406  * @}
407  */
408 
409 /* packet functions */
410 
411 
412 /**
413  * Allocate and read the payload of a packet and initialize its
414  * fields with default values.
415  *
416  * @param s associated IO context
417  * @param pkt packet
418  * @param size desired payload size
419  * @return >0 (read size) if OK, AVERROR_xxx otherwise
420  */
422 
423 
424 /**
425  * Read data and append it to the current content of the AVPacket.
426  * If pkt->size is 0 this is identical to av_get_packet.
427  * Note that this uses av_grow_packet and thus involves a realloc
428  * which is inefficient. Thus this function should only be used
429  * when there is no reasonable way to know (an upper bound of)
430  * the final size.
431  *
432  * @param s associated IO context
433  * @param pkt packet
434  * @param size amount of data to read
435  * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data
436  * will not be lost even if an error occurs.
437  */
439 
440 #if FF_API_LAVF_FRAC
441 /*************************************************/
442 /* fractional numbers for exact pts handling */
443 
444 /**
445  * The exact value of the fractional number is: 'val + num / den'.
446  * num is assumed to be 0 <= num < den.
447  */
448 typedef struct AVFrac {
449  int64_t val, num, den;
450 } AVFrac;
451 #endif
452 
453 /*************************************************/
454 /* input/output formats */
455 
456 struct AVCodecTag;
457 
458 /**
459  * This structure contains the data a format has to probe a file.
460  */
461 typedef struct AVProbeData {
462  const char *filename;
463  unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
464  int buf_size; /**< Size of buf except extra allocated bytes */
465  const char *mime_type; /**< mime_type, when known. */
466 } AVProbeData;
467 
468 #define AVPROBE_SCORE_RETRY (AVPROBE_SCORE_MAX/4)
469 #define AVPROBE_SCORE_STREAM_RETRY (AVPROBE_SCORE_MAX/4-1)
470 
471 #define AVPROBE_SCORE_EXTENSION 50 ///< score for file extension
472 #define AVPROBE_SCORE_MIME 75 ///< score for file mime type
473 #define AVPROBE_SCORE_MAX 100 ///< maximum score
474 
475 #define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
476 
477 /// Demuxer will use avio_open, no opened file should be provided by the caller.
478 #define AVFMT_NOFILE 0x0001
479 #define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
480 #define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
481 #if FF_API_LAVF_FMT_RAWPICTURE
482 #define AVFMT_RAWPICTURE 0x0020 /**< Format wants AVPicture structure for
483  raw picture data. @deprecated Not used anymore */
484 #endif
485 #define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
486 #define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
487 #define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
488 #define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */
489 #define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */
490 #define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */
491 #define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */
492 #define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fall back on binary search via read_timestamp */
493 #define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fall back on generic search */
494 #define AVFMT_NO_BYTE_SEEK 0x8000 /**< Format does not allow seeking by bytes */
495 #define AVFMT_ALLOW_FLUSH 0x10000 /**< Format allows flushing. If not set, the muxer will not receive a NULL packet in the write_packet function. */
496 #define AVFMT_TS_NONSTRICT 0x20000 /**< Format does not require strictly
497  increasing timestamps, but they must
498  still be monotonic */
499 #define AVFMT_TS_NEGATIVE 0x40000 /**< Format allows muxing negative
500  timestamps. If not set the timestamp
501  will be shifted in av_write_frame and
502  av_interleaved_write_frame so they
503  start from 0.
504  The user or muxer can override this through
505  AVFormatContext.avoid_negative_ts
506  */
507 
508 #define AVFMT_SEEK_TO_PTS 0x4000000 /**< Seeking is based on PTS */
509 
510 /**
511  * @addtogroup lavf_encoding
512  * @{
513  */
514 typedef struct AVOutputFormat {
515  const char *name;
516  /**
517  * Descriptive name for the format, meant to be more human-readable
518  * than name. You should use the NULL_IF_CONFIG_SMALL() macro
519  * to define it.
520  */
521  const char *long_name;
522  const char *mime_type;
523  const char *extensions; /**< comma-separated filename extensions */
524  /* output support */
525  enum AVCodecID audio_codec; /**< default audio codec */
526  enum AVCodecID video_codec; /**< default video codec */
527  enum AVCodecID subtitle_codec; /**< default subtitle codec */
528  /**
529  * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER,
530  * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
531  * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH,
532  * AVFMT_TS_NONSTRICT, AVFMT_TS_NEGATIVE
533  */
534  int flags;
536  /**
537  * List of supported codec_id-codec_tag pairs, ordered by "better
538  * choice first". The arrays are all terminated by AV_CODEC_ID_NONE.
539  */
540  const struct AVCodecTag * const *codec_tag;
541 
542 
543  const AVClass *priv_class; ///< AVClass for the private context
544 
545  /*****************************************************************
546  * No fields below this line are part of the public API. They
547  * may not be used outside of libavformat and can be changed and
548  * removed at will.
549  * New public fields should be added right above.
550  *****************************************************************
551  */
553  /**
554  * size of private data so that it can be allocated in the wrapper
555  */
556  int priv_data_size;
557 
558  int (*write_header)(struct AVFormatContext *);
559  /**
560  * Write a packet. If AVFMT_ALLOW_FLUSH is set in flags,
561  * pkt can be NULL in order to flush data buffered in the muxer.
562  * When flushing, return 0 if there still is more data to flush,
563  * or 1 if everything was flushed and there is no more buffered
564  * data.
565  */
568  /**
569  * Currently only used to set pixel format if not YUV420P.
570  */
572  AVPacket *in, int flush);
573  /**
574  * Test if the given codec can be stored in this container.
575  *
576  * @return 1 if the codec is supported, 0 if it is not.
577  * A negative number if unknown.
578  * MKTAG('A', 'P', 'I', 'C') if the codec is only supported as AV_DISPOSITION_ATTACHED_PIC
579  */
580  int (*query_codec)(enum AVCodecID id, int std_compliance);
581 
582  void (*get_output_timestamp)(struct AVFormatContext *s, int stream,
583  int64_t *dts, int64_t *wall);
584  /**
585  * Allows sending messages from application to device.
586  */
587  int (*control_message)(struct AVFormatContext *s, int type,
588  void *data, size_t data_size);
590  /**
591  * Write an uncoded AVFrame.
592  *
593  * See av_write_uncoded_frame() for details.
594  *
595  * The library will free *frame afterwards, but the muxer can prevent it
596  * by setting the pointer to NULL.
597  */
598  int (*write_uncoded_frame)(struct AVFormatContext *, int stream_index,
599  AVFrame **frame, unsigned flags);
600  /**
601  * Returns device list with it properties.
602  * @see avdevice_list_devices() for more details.
603  */
604  int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
605  /**
606  * Initialize device capabilities submodule.
607  * @see avdevice_capabilities_create() for more details.
608  */
610  /**
611  * Free device capabilities submodule.
612  * @see avdevice_capabilities_free() for more details.
613  */
615  enum AVCodecID data_codec; /**< default data codec */
616  /**
617  * Initialize format. May allocate data here, and set any AVFormatContext or
618  * AVStream parameters that need to be set before packets are sent.
619  * This method must not write output.
620  *
621  * Return 0 if streams were fully configured, 1 if not, negative AVERROR on failure
622  *
623  * Any allocations made here must be freed in deinit().
624  */
625  int (*init)(struct AVFormatContext *);
626  /**
627  * Deinitialize format. If present, this is called whenever the muxer is being
628  * destroyed, regardless of whether or not the header has been written.
629  *
630  * If a trailer is being written, this is called after write_trailer().
631  *
632  * This is called if init() fails as well.
633  */
635  /**
636  * Set up any necessary bitstream filtering and extract any extra data needed
637  * for the global header.
638  * Return 0 if more packets from this stream must be checked; 1 if not.
639  */
640  int (*check_bitstream)(struct AVFormatContext *, const AVPacket *pkt);
642 /**
643  * @}
644  */
645 
646 /**
647  * @addtogroup lavf_decoding
648  * @{
649  */
650 typedef struct AVInputFormat {
651  /**
652  * A comma separated list of short names for the format. New names
653  * may be appended with a minor bump.
654  */
655  const char *name;
656 
657  /**
658  * Descriptive name for the format, meant to be more human-readable
659  * than name. You should use the NULL_IF_CONFIG_SMALL() macro
660  * to define it.
661  */
662  const char *long_name;
663 
664  /**
665  * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
666  * AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
667  * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK, AVFMT_SEEK_TO_PTS.
668  */
669  int flags;
670 
671  /**
672  * If extensions are defined, then no probe is done. You should
673  * usually not use extension format guessing because it is not
674  * reliable enough
675  */
676  const char *extensions;
677 
678  const struct AVCodecTag * const *codec_tag;
679 
680  const AVClass *priv_class; ///< AVClass for the private context
681 
682  /**
683  * Comma-separated list of mime types.
684  * It is used check for matching mime types while probing.
685  * @see av_probe_input_format2
686  */
687  const char *mime_type;
688 
689  /*****************************************************************
690  * No fields below this line are part of the public API. They
691  * may not be used outside of libavformat and can be changed and
692  * removed at will.
693  * New public fields should be added right above.
694  *****************************************************************
695  */
697 
698  /**
699  * Raw demuxers store their codec ID here.
700  */
701  int raw_codec_id;
702 
703  /**
704  * Size of private data so that it can be allocated in the wrapper.
705  */
706  int priv_data_size;
707 
708  /**
709  * Tell if a given file has a chance of being parsed as this format.
710  * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
711  * big so you do not have to check for that unless you need more.
712  */
713  int (*read_probe)(AVProbeData *);
714 
715  /**
716  * Read the format header and initialize the AVFormatContext
717  * structure. Return 0 if OK. 'avformat_new_stream' should be
718  * called to create new streams.
719  */
720  int (*read_header)(struct AVFormatContext *);
721 
722  /**
723  * Read one packet and put it in 'pkt'. pts and flags are also
724  * set. 'avformat_new_stream' can be called only if the flag
725  * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
726  * background thread).
727  * @return 0 on success, < 0 on error.
728  * When returning an error, pkt must not have been allocated
729  * or must be freed before returning
730  */
731  int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
732 
733  /**
734  * Close the stream. The AVFormatContext and AVStreams are not
735  * freed by this function
736  */
737  int (*read_close)(struct AVFormatContext *);
738 
739  /**
740  * Seek to a given timestamp relative to the frames in
741  * stream component stream_index.
742  * @param stream_index Must not be -1.
743  * @param flags Selects which direction should be preferred if no exact
744  * match is available.
745  * @return >= 0 on success (but not necessarily the new offset)
746  */
747  int (*read_seek)(struct AVFormatContext *,
748  int stream_index, int64_t timestamp, int flags);
749 
750  /**
751  * Get the next timestamp in stream[stream_index].time_base units.
752  * @return the timestamp or AV_NOPTS_VALUE if an error occurred
753  */
754  int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
755  int64_t *pos, int64_t pos_limit);
757  /**
758  * Start/resume playing - only meaningful if using a network-based format
759  * (RTSP).
760  */
761  int (*read_play)(struct AVFormatContext *);
762 
763  /**
764  * Pause playing - only meaningful if using a network-based format
765  * (RTSP).
766  */
767  int (*read_pause)(struct AVFormatContext *);
768 
769  /**
770  * Seek to timestamp ts.
771  * Seeking will be done so that the point from which all active streams
772  * can be presented successfully will be closest to ts and within min/max_ts.
773  * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
774  */
775  int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
777  /**
778  * Returns device list with it properties.
779  * @see avdevice_list_devices() for more details.
780  */
781  int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
782 
783  /**
784  * Initialize device capabilities submodule.
785  * @see avdevice_capabilities_create() for more details.
786  */
788 
789  /**
790  * Free device capabilities submodule.
791  * @see avdevice_capabilities_free() for more details.
792  */
794 } AVInputFormat;
795 /**
796  * @}
797  */
798 
799 enum AVStreamParseType {
801  AVSTREAM_PARSE_FULL, /**< full parsing and repack */
802  AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
803  AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
804  AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
805  AVSTREAM_PARSE_FULL_RAW=MKTAG(0,'R','A','W'), /**< full parsing and repack with timestamp and position generation by parser for raw
806  this assumes that each packet in the file contains no demuxer level headers and
807  just codec level data, otherwise position generation would fail */
808 };
810 typedef struct AVIndexEntry {
811  int64_t pos;
812  int64_t timestamp; /**<
813  * Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are available
814  * when seeking to this entry. That means preferable PTS on keyframe based formats.
815  * But demuxers can choose to store a different timestamp, if it is more convenient for the implementation or nothing better
816  * is known
817  */
818 #define AVINDEX_KEYFRAME 0x0001
819 #define AVINDEX_DISCARD_FRAME 0x0002 /**
820  * Flag is used to indicate which frame should be discarded after decoding.
821  */
822  int flags:2;
823  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).
824  int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
825 } AVIndexEntry;
826 
827 #define AV_DISPOSITION_DEFAULT 0x0001
828 #define AV_DISPOSITION_DUB 0x0002
829 #define AV_DISPOSITION_ORIGINAL 0x0004
830 #define AV_DISPOSITION_COMMENT 0x0008
831 #define AV_DISPOSITION_LYRICS 0x0010
832 #define AV_DISPOSITION_KARAOKE 0x0020
834 /**
835  * Track should be used during playback by default.
836  * Useful for subtitle track that should be displayed
837  * even when user did not explicitly ask for subtitles.
838  */
839 #define AV_DISPOSITION_FORCED 0x0040
840 #define AV_DISPOSITION_HEARING_IMPAIRED 0x0080 /**< stream for hearing impaired audiences */
841 #define AV_DISPOSITION_VISUAL_IMPAIRED 0x0100 /**< stream for visual impaired audiences */
842 #define AV_DISPOSITION_CLEAN_EFFECTS 0x0200 /**< stream without voice */
843 /**
844  * The stream is stored in the file as an attached picture/"cover art" (e.g.
845  * APIC frame in ID3v2). The first (usually only) packet associated with it
846  * will be returned among the first few packets read from the file unless
847  * seeking takes place. It can also be accessed at any time in
848  * AVStream.attached_pic.
849  */
850 #define AV_DISPOSITION_ATTACHED_PIC 0x0400
851 /**
852  * The stream is sparse, and contains thumbnail images, often corresponding
853  * to chapter markers. Only ever used with AV_DISPOSITION_ATTACHED_PIC.
854  */
855 #define AV_DISPOSITION_TIMED_THUMBNAILS 0x0800
856 
857 typedef struct AVStreamInternal AVStreamInternal;
858 
859 /**
860  * To specify text track kind (different from subtitles default).
861  */
862 #define AV_DISPOSITION_CAPTIONS 0x10000
863 #define AV_DISPOSITION_DESCRIPTIONS 0x20000
864 #define AV_DISPOSITION_METADATA 0x40000
865 
866 /**
867  * Options for behavior on timestamp wrap detection.
868  */
869 #define AV_PTS_WRAP_IGNORE 0 ///< ignore the wrap
870 #define AV_PTS_WRAP_ADD_OFFSET 1 ///< add the format specific offset on wrap detection
871 #define AV_PTS_WRAP_SUB_OFFSET -1 ///< subtract the format specific offset on wrap detection
873 /**
874  * Stream structure.
875  * New fields can be added to the end with minor version bumps.
876  * Removal, reordering and changes to existing fields require a major
877  * version bump.
878  * sizeof(AVStream) must not be used outside libav*.
879  */
880 typedef struct AVStream {
881  int index; /**< stream index in AVFormatContext */
882  /**
883  * Format-specific stream ID.
884  * decoding: set by libavformat
885  * encoding: set by the user, replaced by libavformat if left unset
886  */
887  int id;
888 #if FF_API_LAVF_AVCTX
889  /**
890  * @deprecated use the codecpar struct instead
891  */
893  AVCodecContext *codec;
894 #endif
895  void *priv_data;
897 #if FF_API_LAVF_FRAC
898  /**
899  * @deprecated this field is unused
900  */
902  struct AVFrac pts;
903 #endif
905  /**
906  * This is the fundamental unit of time (in seconds) in terms
907  * of which frame timestamps are represented.
908  *
909  * decoding: set by libavformat
910  * encoding: May be set by the caller before avformat_write_header() to
911  * provide a hint to the muxer about the desired timebase. In
912  * avformat_write_header(), the muxer will overwrite this field
913  * with the timebase that will actually be used for the timestamps
914  * written into the file (which may or may not be related to the
915  * user-provided one, depending on the format).
916  */
918 
919  /**
920  * Decoding: pts of the first frame of the stream in presentation order, in stream time base.
921  * Only set this if you are absolutely 100% sure that the value you set
922  * it to really is the pts of the first frame.
923  * This may be undefined (AV_NOPTS_VALUE).
924  * @note The ASF header does NOT contain a correct start_time the ASF
925  * demuxer must NOT set this.
926  */
927  int64_t start_time;
928 
929  /**
930  * Decoding: duration of the stream, in stream time base.
931  * If a source file does not specify a duration, but does specify
932  * a bitrate, this value will be estimated from bitrate and file size.
933  */
934  int64_t duration;
935 
936  int64_t nb_frames; ///< number of frames in this stream if known or 0
937 
938  int disposition; /**< AV_DISPOSITION_* bit field */
939 
940  enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
941 
942  /**
943  * sample aspect ratio (0 if unknown)
944  * - encoding: Set by user.
945  * - decoding: Set by libavformat.
946  */
948 
950 
951  /**
952  * Average framerate
953  *
954  * - demuxing: May be set by libavformat when creating the stream or in
955  * avformat_find_stream_info().
956  * - muxing: May be set by the caller before avformat_write_header().
957  */
959 
960  /**
961  * For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet
962  * will contain the attached picture.
963  *
964  * decoding: set by libavformat, must not be modified by the caller.
965  * encoding: unused
966  */
968 
969  /**
970  * An array of side data that applies to the whole stream (i.e. the
971  * container does not allow it to change between packets).
972  *
973  * There may be no overlap between the side data in this array and side data
974  * in the packets. I.e. a given side data is either exported by the muxer
975  * (demuxing) / set by the caller (muxing) in this array, then it never
976  * appears in the packets, or the side data is exported / sent through
977  * the packets (always in the first packet where the value becomes known or
978  * changes), then it does not appear in this array.
979  *
980  * - demuxing: Set by libavformat when the stream is created.
981  * - muxing: May be set by the caller before avformat_write_header().
982  *
983  * Freed by libavformat in avformat_free_context().
984  *
985  * @see av_format_inject_global_side_data()
986  */
988  /**
989  * The number of elements in the AVStream.side_data array.
990  */
991  int nb_side_data;
992 
993  /**
994  * Flags for the user to detect events happening on the stream. Flags must
995  * be cleared by the user once the event has been handled.
996  * A combination of AVSTREAM_EVENT_FLAG_*.
997  */
998  int event_flags;
999 #define AVSTREAM_EVENT_FLAG_METADATA_UPDATED 0x0001 ///< The call resulted in updated metadata.
1001  /*****************************************************************
1002  * All fields below this line are not part of the public API. They
1003  * may not be used outside of libavformat and can be changed and
1004  * removed at will.
1005  * New public fields should be added right above.
1006  *****************************************************************
1007  */
1009  /**
1010  * Stream information used internally by avformat_find_stream_info()
1011  */
1012 #define MAX_STD_TIMEBASES (30*12+30+3+6)
1013  struct {
1014  int64_t last_dts;
1015  int64_t duration_gcd;
1016  int duration_count;
1017  int64_t rfps_duration_sum;
1018  double (*duration_error)[2][MAX_STD_TIMEBASES];
1019  int64_t codec_info_duration;
1022  /**
1023  * 0 -> decoder has not been searched for yet.
1024  * >0 -> decoder found
1025  * <0 -> decoder with codec_id == -found_decoder has not been found
1026  */
1029  int64_t last_duration;
1030 
1031  /**
1032  * Those are used for average framerate estimation.
1033  */
1034  int64_t fps_first_dts;
1035  int fps_first_dts_idx;
1036  int64_t fps_last_dts;
1037  int fps_last_dts_idx;
1039  } *info;
1040 
1041  int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
1042 
1043  // Timestamp generation support:
1044  /**
1045  * Timestamp corresponding to the last dts sync point.
1046  *
1047  * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
1048  * a DTS is received from the underlying container. Otherwise set to
1049  * AV_NOPTS_VALUE by default.
1050  */
1051  int64_t first_dts;
1052  int64_t cur_dts;
1053  int64_t last_IP_pts;
1054  int last_IP_duration;
1055 
1056  /**
1057  * Number of packets to buffer for codec probing
1058  */
1059  int probe_packets;
1061  /**
1062  * Number of frames that have been demuxed during avformat_find_stream_info()
1063  */
1065 
1066  /* av_read_frame() support */
1069 
1070  /**
1071  * last packet in packet_buffer for this stream when muxing.
1072  */
1075 #define MAX_REORDER_DELAY 16
1078  AVIndexEntry *index_entries; /**< Only used if the format does not
1079  support seeking natively. */
1080  int nb_index_entries;
1081  unsigned int index_entries_allocated_size;
1083  /**
1084  * Real base framerate of the stream.
1085  * This is the lowest framerate with which all timestamps can be
1086  * represented accurately (it is the least common multiple of all
1087  * framerates in the stream). Note, this value is just a guess!
1088  * For example, if the time base is 1/90000 and all frames have either
1089  * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
1090  *
1091  * Code outside avformat should access this field using:
1092  * av_stream_get/set_r_frame_rate(stream)
1093  */
1095 
1096  /**
1097  * Stream Identifier
1098  * This is the MPEG-TS stream identifier +1
1099  * 0 means unknown
1100  */
1101  int stream_identifier;
1102 
1105 
1106  /**
1107  * stream probing state
1108  * -1 -> probing finished
1109  * 0 -> no probing requested
1110  * rest -> perform probing with request_probe being the minimum score to accept.
1111  * NOT PART OF PUBLIC API
1112  */
1114  /**
1115  * Indicates that everything up to the next keyframe
1116  * should be discarded.
1117  */
1118  int skip_to_keyframe;
1119 
1120  /**
1121  * Number of samples to skip at the start of the frame decoded from the next packet.
1122  */
1123  int skip_samples;
1124 
1125  /**
1126  * If not 0, the number of samples that should be skipped from the start of
1127  * the stream (the samples are removed from packets with pts==0, which also
1128  * assumes negative timestamps do not happen).
1129  * Intended for use with formats such as mp3 with ad-hoc gapless audio
1130  * support.
1131  */
1133 
1134  /**
1135  * If not 0, the first audio sample that should be discarded from the stream.
1136  * This is broken by design (needs global sample count), but can't be
1137  * avoided for broken by design formats such as mp3 with ad-hoc gapless
1138  * audio support.
1139  */
1140  int64_t first_discard_sample;
1142  /**
1143  * The sample after last sample that is intended to be discarded after
1144  * first_discard_sample. Works on frame boundaries only. Used to prevent
1145  * early EOF if the gapless info is broken (considered concatenated mp3s).
1146  */
1147  int64_t last_discard_sample;
1148 
1149  /**
1150  * Number of internally decoded frames, used internally in libavformat, do not access
1151  * its lifetime differs from info which is why it is not in that structure.
1152  */
1153  int nb_decoded_frames;
1154 
1155  /**
1156  * Timestamp offset added to timestamps before muxing
1157  * NOT PART OF PUBLIC API
1158  */
1159  int64_t mux_ts_offset;
1160 
1161  /**
1162  * Internal data to check for wrapping of the time stamp
1163  */
1164  int64_t pts_wrap_reference;
1165 
1166  /**
1167  * Options for behavior, when a wrap is detected.
1168  *
1169  * Defined by AV_PTS_WRAP_ values.
1170  *
1171  * If correction is enabled, there are two possibilities:
1172  * If the first time stamp is near the wrap point, the wrap offset
1173  * will be subtracted, which will create negative time stamps.
1174  * Otherwise the offset will be added.
1175  */
1176  int pts_wrap_behavior;
1177 
1178  /**
1179  * Internal data to prevent doing update_initial_durations() twice
1180  */
1182 
1183  /**
1184  * Internal data to generate dts from pts
1185  */
1188 
1189  /**
1190  * Internal data to analyze DTS and detect faulty mpeg streams
1191  */
1192  int64_t last_dts_for_order_check;
1196  /**
1197  * Internal data to inject global side data
1198  */
1200 
1201  /**
1202  * String containing paris of key and values describing recommended encoder configuration.
1203  * Paris are separated by ','.
1204  * Keys are separated from values by '='.
1205  */
1207 
1208  /**
1209  * display aspect ratio (0 if unknown)
1210  * - encoding: unused
1211  * - decoding: Set by libavformat to calculate sample_aspect_ratio internally
1212  */
1214 
1215  struct FFFrac *priv_pts;
1216 
1217  /**
1218  * An opaque field for libavformat internal usage.
1219  * Must not be accessed in any way by callers.
1220  */
1221  AVStreamInternal *internal;
1223  /*
1224  * Codec parameters associated with this stream. Allocated and freed by
1225  * libavformat in avformat_new_stream() and avformat_free_context()
1226  * respectively.
1227  *
1228  * - demuxing: filled by libavformat on stream creation or in
1229  * avformat_find_stream_info()
1230  * - muxing: filled by the caller before avformat_write_header()
1231  */
1233 } AVStream;
1234 
1239 void av_stream_set_recommended_encoder_configuration(AVStream *s, char *configuration);
1240 
1241 /**
1242  * Returns the pts of the last muxed packet + its duration
1243  *
1244  * the retuned value is undefined when used with a demuxer.
1245  */
1246 int64_t av_stream_get_end_pts(const AVStream *st);
1247 
1248 #define AV_PROGRAM_RUNNING 1
1249 
1250 /**
1251  * New fields can be added to the end with minor version bumps.
1252  * Removal, reordering and changes to existing fields require a major
1253  * version bump.
1254  * sizeof(AVProgram) must not be used outside libav*.
1255  */
1256 typedef struct AVProgram {
1257  int id;
1258  int flags;
1259  enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
1260  unsigned int *stream_index;
1261  unsigned int nb_stream_indexes;
1263 
1264  int program_num;
1265  int pmt_pid;
1266  int pcr_pid;
1268  /*****************************************************************
1269  * All fields below this line are not part of the public API. They
1270  * may not be used outside of libavformat and can be changed and
1271  * removed at will.
1272  * New public fields should be added right above.
1273  *****************************************************************
1274  */
1275  int64_t start_time;
1276  int64_t end_time;
1277 
1278  int64_t pts_wrap_reference; ///< reference dts for wrap detection
1279  int pts_wrap_behavior; ///< behavior on wrap detection
1280 } AVProgram;
1281 
1282 #define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
1283  (streams are added dynamically) */
1285 typedef struct AVChapter {
1286  int id; ///< unique ID to identify the chapter
1287  AVRational time_base; ///< time base in which the start/end timestamps are specified
1288  int64_t start, end; ///< chapter start/end time in time_base units
1290 } AVChapter;
1292 
1293 /**
1294  * Callback used by devices to communicate with application.
1295  */
1297  void *data, size_t data_size);
1299 typedef int (*AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags,
1301 
1302 /**
1303  * The duration of a video can be estimated through various ways, and this enum can be used
1304  * to know how the duration was estimated.
1305  */
1307  AVFMT_DURATION_FROM_PTS, ///< Duration accurately estimated from PTSes
1308  AVFMT_DURATION_FROM_STREAM, ///< Duration estimated from a stream with a known duration
1309  AVFMT_DURATION_FROM_BITRATE ///< Duration estimated from bitrate (less accurate)
1310 };
1311 
1312 typedef struct AVFormatInternal AVFormatInternal;
1313 
1314 /**
1315  * Format I/O context.
1316  * New fields can be added to the end with minor version bumps.
1317  * Removal, reordering and changes to existing fields require a major
1318  * version bump.
1319  * sizeof(AVFormatContext) must not be used outside libav*, use
1320  * avformat_alloc_context() to create an AVFormatContext.
1321  *
1322  * Fields can be accessed through AVOptions (av_opt*),
1323  * the name string used matches the associated command line parameter name and
1324  * can be found in libavformat/options_table.h.
1325  * The AVOption/command line parameter names differ in some cases from the C
1326  * structure field names for historic reasons or brevity.
1327  */
1328 typedef struct AVFormatContext {
1329  /**
1330  * A class for logging and @ref avoptions. Set by avformat_alloc_context().
1331  * Exports (de)muxer private options if they exist.
1332  */
1333  const AVClass *av_class;
1334 
1335  /**
1336  * The input container format.
1337  *
1338  * Demuxing only, set by avformat_open_input().
1339  */
1340  struct AVInputFormat *iformat;
1341 
1342  /**
1343  * The output container format.
1344  *
1345  * Muxing only, must be set by the caller before avformat_write_header().
1346  */
1347  struct AVOutputFormat *oformat;
1348 
1349  /**
1350  * Format private data. This is an AVOptions-enabled struct
1351  * if and only if iformat/oformat.priv_class is not NULL.
1352  *
1353  * - muxing: set by avformat_write_header()
1354  * - demuxing: set by avformat_open_input()
1355  */
1356  void *priv_data;
1358  /**
1359  * I/O context.
1360  *
1361  * - demuxing: either set by the user before avformat_open_input() (then
1362  * the user must close it manually) or set by avformat_open_input().
1363  * - muxing: set by the user before avformat_write_header(). The caller must
1364  * take care of closing / freeing the IO context.
1365  *
1366  * Do NOT set this field if AVFMT_NOFILE flag is set in
1367  * iformat/oformat.flags. In such a case, the (de)muxer will handle
1368  * I/O in some other way and this field will be NULL.
1369  */
1370  AVIOContext *pb;
1371 
1372  /* stream info */
1373  /**
1374  * Flags signalling stream properties. A combination of AVFMTCTX_*.
1375  * Set by libavformat.
1376  */
1377  int ctx_flags;
1378 
1379  /**
1380  * Number of elements in AVFormatContext.streams.
1381  *
1382  * Set by avformat_new_stream(), must not be modified by any other code.
1383  */
1384  unsigned int nb_streams;
1385  /**
1386  * A list of all streams in the file. New streams are created with
1387  * avformat_new_stream().
1388  *
1389  * - demuxing: streams are created by libavformat in avformat_open_input().
1390  * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
1391  * appear in av_read_frame().
1392  * - muxing: streams are created by the user before avformat_write_header().
1393  *
1394  * Freed by libavformat in avformat_free_context().
1395  */
1396  AVStream **streams;
1397 
1398  /**
1399  * input or output filename
1400  *
1401  * - demuxing: set by avformat_open_input()
1402  * - muxing: may be set by the caller before avformat_write_header()
1403  */
1404  char filename[1024];
1405 
1406  /**
1407  * Position of the first frame of the component, in
1408  * AV_TIME_BASE fractional seconds. NEVER set this value directly:
1409  * It is deduced from the AVStream values.
1410  *
1411  * Demuxing only, set by libavformat.
1412  */
1413  int64_t start_time;
1415  /**
1416  * Duration of the stream, in AV_TIME_BASE fractional
1417  * seconds. Only set this value if you know none of the individual stream
1418  * durations and also do not set any of them. This is deduced from the
1419  * AVStream values if not set.
1420  *
1421  * Demuxing only, set by libavformat.
1422  */
1423  int64_t duration;
1424 
1425  /**
1426  * Total stream bitrate in bit/s, 0 if not
1427  * available. Never set it directly if the file_size and the
1428  * duration are known as FFmpeg can compute it automatically.
1429  */
1430  int64_t bit_rate;
1431 
1432  unsigned int packet_size;
1434 
1435  /**
1436  * Flags modifying the (de)muxer behaviour. A combination of AVFMT_FLAG_*.
1437  * Set by the user before avformat_open_input() / avformat_write_header().
1438  */
1439  int flags;
1440 #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
1441 #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
1442 #define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
1443 #define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
1444 #define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
1445 #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
1446 #define AVFMT_FLAG_NOBUFFER 0x0040 ///< Do not buffer frames when possible
1447 #define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
1448 #define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted
1449 #define AVFMT_FLAG_FLUSH_PACKETS 0x0200 ///< Flush the AVIOContext every packet.
1450 /**
1451  * When muxing, try to avoid writing any random/volatile data to the output.
1452  * This includes any random IDs, real-time timestamps/dates, muxer version, etc.
1453  *
1454  * This flag is mainly intended for testing.
1455  */
1456 #define AVFMT_FLAG_BITEXACT 0x0400
1457 #define AVFMT_FLAG_MP4A_LATM 0x8000 ///< Enable RTP MP4A-LATM payload
1458 #define AVFMT_FLAG_SORT_DTS 0x10000 ///< try to interleave outputted packets by dts (using this flag can slow demuxing down)
1459 #define AVFMT_FLAG_PRIV_OPT 0x20000 ///< Enable use of private options by delaying codec open (this could be made default once all code is converted)
1460 #define AVFMT_FLAG_KEEP_SIDE_DATA 0x40000 ///< Don't merge side data but keep it separate.
1461 #define AVFMT_FLAG_FAST_SEEK 0x80000 ///< Enable fast, but inaccurate seeks for some formats
1462 #define AVFMT_FLAG_SHORTEST 0x100000 ///< Stop muxing when the shortest stream stops.
1463 #define AVFMT_FLAG_AUTO_BSF 0x200000 ///< Wait for packet data before writing a header, and add bitstream filters as requested by the muxer
1464 
1465  /**
1466  * Maximum size of the data read from input for determining
1467  * the input container format.
1468  * Demuxing only, set by the caller before avformat_open_input().
1469  */
1470  int64_t probesize;
1472  /**
1473  * Maximum duration (in AV_TIME_BASE units) of the data read
1474  * from input in avformat_find_stream_info().
1475  * Demuxing only, set by the caller before avformat_find_stream_info().
1476  * Can be set to 0 to let avformat choose using a heuristic.
1477  */
1478  int64_t max_analyze_duration;
1479 
1480  const uint8_t *key;
1481  int keylen;
1482 
1483  unsigned int nb_programs;
1484  AVProgram **programs;
1485 
1486  /**
1487  * Forced video codec_id.
1488  * Demuxing: Set by user.
1489  */
1492  /**
1493  * Forced audio codec_id.
1494  * Demuxing: Set by user.
1495  */
1497 
1498  /**
1499  * Forced subtitle codec_id.
1500  * Demuxing: Set by user.
1501  */
1503 
1504  /**
1505  * Maximum amount of memory in bytes to use for the index of each stream.
1506  * If the index exceeds this size, entries will be discarded as
1507  * needed to maintain a smaller size. This can lead to slower or less
1508  * accurate seeking (depends on demuxer).
1509  * Demuxers for which a full in-memory index is mandatory will ignore
1510  * this.
1511  * - muxing: unused
1512  * - demuxing: set by user
1513  */
1514  unsigned int max_index_size;
1515 
1516  /**
1517  * Maximum amount of memory in bytes to use for buffering frames
1518  * obtained from realtime capture devices.
1519  */
1520  unsigned int max_picture_buffer;
1521 
1522  /**
1523  * Number of chapters in AVChapter array.
1524  * When muxing, chapters are normally written in the file header,
1525  * so nb_chapters should normally be initialized before write_header
1526  * is called. Some muxers (e.g. mov and mkv) can also write chapters
1527  * in the trailer. To write chapters in the trailer, nb_chapters
1528  * must be zero when write_header is called and non-zero when
1529  * write_trailer is called.
1530  * - muxing: set by user
1531  * - demuxing: set by libavformat
1532  */
1533  unsigned int nb_chapters;
1534  AVChapter **chapters;
1535 
1536  /**
1537  * Metadata that applies to the whole file.
1538  *
1539  * - demuxing: set by libavformat in avformat_open_input()
1540  * - muxing: may be set by the caller before avformat_write_header()
1541  *
1542  * Freed by libavformat in avformat_free_context().
1543  */
1545 
1546  /**
1547  * Start time of the stream in real world time, in microseconds
1548  * since the Unix epoch (00:00 1st January 1970). That is, pts=0 in the
1549  * stream was captured at this real world time.
1550  * - muxing: Set by the caller before avformat_write_header(). If set to
1551  * either 0 or AV_NOPTS_VALUE, then the current wall-time will
1552  * be used.
1553  * - demuxing: Set by libavformat. AV_NOPTS_VALUE if unknown. Note that
1554  * the value may become known after some number of frames
1555  * have been received.
1556  */
1557  int64_t start_time_realtime;
1558 
1559  /**
1560  * The number of frames used for determining the framerate in
1561  * avformat_find_stream_info().
1562  * Demuxing only, set by the caller before avformat_find_stream_info().
1563  */
1564  int fps_probe_size;
1565 
1566  /**
1567  * Error recognition; higher values will detect more errors but may
1568  * misdetect some more or less valid parts as errors.
1569  * Demuxing only, set by the caller before avformat_open_input().
1570  */
1571  int error_recognition;
1572 
1573  /**
1574  * Custom interrupt callbacks for the I/O layer.
1575  *
1576  * demuxing: set by the user before avformat_open_input().
1577  * muxing: set by the user before avformat_write_header()
1578  * (mainly useful for AVFMT_NOFILE formats). The callback
1579  * should also be passed to avio_open2() if it's used to
1580  * open the file.
1581  */
1583 
1584  /**
1585  * Flags to enable debugging.
1586  */
1587  int debug;
1588 #define FF_FDEBUG_TS 0x0001
1589 
1590  /**
1591  * Maximum buffering duration for interleaving.
1592  *
1593  * To ensure all the streams are interleaved correctly,
1594  * av_interleaved_write_frame() will wait until it has at least one packet
1595  * for each stream before actually writing any packets to the output file.
1596  * When some streams are "sparse" (i.e. there are large gaps between
1597  * successive packets), this can result in excessive buffering.
1598  *
1599  * This field specifies the maximum difference between the timestamps of the
1600  * first and the last packet in the muxing queue, above which libavformat
1601  * will output a packet regardless of whether it has queued a packet for all
1602  * the streams.
1603  *
1604  * Muxing only, set by the caller before avformat_write_header().
1605  */
1606  int64_t max_interleave_delta;
1607 
1608  /**
1609  * Allow non-standard and experimental extension
1610  * @see AVCodecContext.strict_std_compliance
1611  */
1613 
1614  /**
1615  * Flags for the user to detect events happening on the file. Flags must
1616  * be cleared by the user once the event has been handled.
1617  * A combination of AVFMT_EVENT_FLAG_*.
1618  */
1619  int event_flags;
1620 #define AVFMT_EVENT_FLAG_METADATA_UPDATED 0x0001 ///< The call resulted in updated metadata.
1621 
1622  /**
1623  * Maximum number of packets to read while waiting for the first timestamp.
1624  * Decoding only.
1625  */
1626  int max_ts_probe;
1627 
1628  /**
1629  * Avoid negative timestamps during muxing.
1630  * Any value of the AVFMT_AVOID_NEG_TS_* constants.
1631  * Note, this only works when using av_interleaved_write_frame. (interleave_packet_per_dts is in use)
1632  * - muxing: Set by user
1633  * - demuxing: unused
1634  */
1635  int avoid_negative_ts;
1636 #define AVFMT_AVOID_NEG_TS_AUTO -1 ///< Enabled when required by target format
1637 #define AVFMT_AVOID_NEG_TS_MAKE_NON_NEGATIVE 1 ///< Shift timestamps so they are non negative
1638 #define AVFMT_AVOID_NEG_TS_MAKE_ZERO 2 ///< Shift timestamps so that they start at 0
1639 
1640  /**
1641  * Transport stream id.
1642  * This will be moved into demuxer private options. Thus no API/ABI compatibility
1643  */
1644  int ts_id;
1646  /**
1647  * Audio preload in microseconds.
1648  * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1649  * - encoding: Set by user via AVOptions (NO direct access)
1650  * - decoding: unused
1651  */
1652  int audio_preload;
1653 
1654  /**
1655  * Max chunk time in microseconds.
1656  * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1657  * - encoding: Set by user via AVOptions (NO direct access)
1658  * - decoding: unused
1659  */
1660  int max_chunk_duration;
1661 
1662  /**
1663  * Max chunk size in bytes
1664  * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1665  * - encoding: Set by user via AVOptions (NO direct access)
1666  * - decoding: unused
1667  */
1668  int max_chunk_size;
1669 
1670  /**
1671  * forces the use of wallclock timestamps as pts/dts of packets
1672  * This has undefined results in the presence of B frames.
1673  * - encoding: unused
1674  * - decoding: Set by user via AVOptions (NO direct access)
1675  */
1677 
1678  /**
1679  * avio flags, used to force AVIO_FLAG_DIRECT.
1680  * - encoding: unused
1681  * - decoding: Set by user via AVOptions (NO direct access)
1682  */
1683  int avio_flags;
1684 
1685  /**
1686  * The duration field can be estimated through various ways, and this field can be used
1687  * to know how the duration was estimated.
1688  * - encoding: unused
1689  * - decoding: Read by user via AVOptions (NO direct access)
1690  */
1692 
1693  /**
1694  * Skip initial bytes when opening stream
1695  * - encoding: unused
1696  * - decoding: Set by user via AVOptions (NO direct access)
1697  */
1698  int64_t skip_initial_bytes;
1699 
1700  /**
1701  * Correct single timestamp overflows
1702  * - encoding: unused
1703  * - decoding: Set by user via AVOptions (NO direct access)
1704  */
1705  unsigned int correct_ts_overflow;
1706 
1707  /**
1708  * Force seeking to any (also non key) frames.
1709  * - encoding: unused
1710  * - decoding: Set by user via AVOptions (NO direct access)
1711  */
1712  int seek2any;
1713 
1714  /**
1715  * Flush the I/O context after each packet.
1716  * - encoding: Set by user via AVOptions (NO direct access)
1717  * - decoding: unused
1718  */
1719  int flush_packets;
1720 
1721  /**
1722  * format probing score.
1723  * The maximal score is AVPROBE_SCORE_MAX, its set when the demuxer probes
1724  * the format.
1725  * - encoding: unused
1726  * - decoding: set by avformat, read by user via av_format_get_probe_score() (NO direct access)
1727  */
1728  int probe_score;
1730  /**
1731  * number of bytes to read maximally to identify format.
1732  * - encoding: unused
1733  * - decoding: set by user through AVOPtions (NO direct access)
1734  */
1735  int format_probesize;
1736 
1737  /**
1738  * ',' separated list of allowed decoders.
1739  * If NULL then all are allowed
1740  * - encoding: unused
1741  * - decoding: set by user through AVOptions (NO direct access)
1742  */
1743  char *codec_whitelist;
1744 
1745  /**
1746  * ',' separated list of allowed demuxers.
1747  * If NULL then all are allowed
1748  * - encoding: unused
1749  * - decoding: set by user through AVOptions (NO direct access)
1750  */
1751  char *format_whitelist;
1752 
1753  /**
1754  * An opaque field for libavformat internal usage.
1755  * Must not be accessed in any way by callers.
1756  */
1757  AVFormatInternal *internal;
1758 
1759  /**
1760  * IO repositioned flag.
1761  * This is set by avformat when the underlaying IO context read pointer
1762  * is repositioned, for example when doing byte based seeking.
1763  * Demuxers can use the flag to detect such changes.
1764  */
1765  int io_repositioned;
1766 
1767  /**
1768  * Forced video codec.
1769  * This allows forcing a specific decoder, even when there are multiple with
1770  * the same codec_id.
1771  * Demuxing: Set by user via av_format_set_video_codec (NO direct access).
1772  */
1774 
1775  /**
1776  * Forced audio codec.
1777  * This allows forcing a specific decoder, even when there are multiple with
1778  * the same codec_id.
1779  * Demuxing: Set by user via av_format_set_audio_codec (NO direct access).
1780  */
1782 
1783  /**
1784  * Forced subtitle codec.
1785  * This allows forcing a specific decoder, even when there are multiple with
1786  * the same codec_id.
1787  * Demuxing: Set by user via av_format_set_subtitle_codec (NO direct access).
1788  */
1790 
1791  /**
1792  * Forced data codec.
1793  * This allows forcing a specific decoder, even when there are multiple with
1794  * the same codec_id.
1795  * Demuxing: Set by user via av_format_set_data_codec (NO direct access).
1796  */
1798 
1799  /**
1800  * Number of bytes to be written as padding in a metadata header.
1801  * Demuxing: Unused.
1802  * Muxing: Set by user via av_format_set_metadata_header_padding.
1803  */
1805 
1806  /**
1807  * User data.
1808  * This is a place for some private data of the user.
1809  */
1810  void *opaque;
1811 
1812  /**
1813  * Callback used by devices to communicate with application.
1814  */
1816 
1817  /**
1818  * Output timestamp offset, in microseconds.
1819  * Muxing: set by user via AVOptions (NO direct access)
1820  */
1821  int64_t output_ts_offset;
1822 
1823  /**
1824  * dump format separator.
1825  * can be ", " or "\n " or anything else
1826  * Code outside libavformat should access this field using AVOptions
1827  * (NO direct access).
1828  * - muxing: Set by user.
1829  * - demuxing: Set by user.
1830  */
1832 
1833  /**
1834  * Forced Data codec_id.
1835  * Demuxing: Set by user.
1836  */
1837  enum AVCodecID data_codec_id;
1838 
1839 #if FF_API_OLD_OPEN_CALLBACKS
1840  /**
1841  * Called to open further IO contexts when needed for demuxing.
1842  *
1843  * This can be set by the user application to perform security checks on
1844  * the URLs before opening them.
1845  * The function should behave like avio_open2(), AVFormatContext is provided
1846  * as contextual information and to reach AVFormatContext.opaque.
1847  *
1848  * If NULL then some simple checks are used together with avio_open2().
1849  *
1850  * Must not be accessed directly from outside avformat.
1851  * @See av_format_set_open_cb()
1852  *
1853  * Demuxing: Set by user.
1854  *
1855  * @deprecated Use io_open and io_close.
1856  */
1858  int (*open_cb)(struct AVFormatContext *s, AVIOContext **p, const char *url, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options);
1859 #endif
1860 
1861  /**
1862  * ',' separated list of allowed protocols.
1863  * - encoding: unused
1864  * - decoding: set by user through AVOptions (NO direct access)
1865  */
1866  char *protocol_whitelist;
1867 
1868  /*
1869  * A callback for opening new IO streams.
1870  *
1871  * Whenever a muxer or a demuxer needs to open an IO stream (typically from
1872  * avformat_open_input() for demuxers, but for certain formats can happen at
1873  * other times as well), it will call this callback to obtain an IO context.
1874  *
1875  * @param s the format context
1876  * @param pb on success, the newly opened IO context should be returned here
1877  * @param url the url to open
1878  * @param flags a combination of AVIO_FLAG_*
1879  * @param options a dictionary of additional options, with the same
1880  * semantics as in avio_open2()
1881  * @return 0 on success, a negative AVERROR code on failure
1882  *
1883  * @note Certain muxers and demuxers do nesting, i.e. they open one or more
1884  * additional internal format contexts. Thus the AVFormatContext pointer
1885  * passed to this callback may be different from the one facing the caller.
1886  * It will, however, have the same 'opaque' field.
1887  */
1888  int (*io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url,
1889  int flags, AVDictionary **options);
1890 
1891  /**
1892  * A callback for closing the streams opened with AVFormatContext.io_open().
1893  */
1894  void (*io_close)(struct AVFormatContext *s, AVIOContext *pb);
1895 
1896  /**
1897  * ',' separated list of disallowed protocols.
1898  * - encoding: unused
1899  * - decoding: set by user through AVOptions (NO direct access)
1900  */
1901  char *protocol_blacklist;
1902 
1903  /**
1904  * The maximum number of streams.
1905  * - encoding: unused
1906  * - decoding: set by user through AVOptions (NO direct access)
1907  */
1908  int max_streams;
1909 } AVFormatContext;
1910 
1922 void * av_format_get_opaque(const AVFormatContext *s);
1926 #if FF_API_OLD_OPEN_CALLBACKS
1927 attribute_deprecated AVOpenCallback av_format_get_open_cb(const AVFormatContext *s);
1928 attribute_deprecated void av_format_set_open_cb(AVFormatContext *s, AVOpenCallback callback);
1929 #endif
1930 
1931 /**
1932  * This function will cause global side data to be injected in the next packet
1933  * of each stream as well as after any subsequent seek.
1934  */
1936 
1937 /**
1938  * Returns the method used to set ctx->duration.
1939  *
1940  * @return AVFMT_DURATION_FROM_PTS, AVFMT_DURATION_FROM_STREAM, or AVFMT_DURATION_FROM_BITRATE.
1941  */
1943 
1944 typedef struct AVPacketList {
1945  AVPacket pkt;
1946  struct AVPacketList *next;
1947 } AVPacketList;
1948 
1949 
1950 /**
1951  * @defgroup lavf_core Core functions
1952  * @ingroup libavf
1953  *
1954  * Functions for querying libavformat capabilities, allocating core structures,
1955  * etc.
1956  * @{
1957  */
1958 
1959 /**
1960  * Return the LIBAVFORMAT_VERSION_INT constant.
1961  */
1962 unsigned avformat_version(void);
1963 
1964 /**
1965  * Return the libavformat build-time configuration.
1966  */
1967 const char *avformat_configuration(void);
1968 
1969 /**
1970  * Return the libavformat license.
1971  */
1972 const char *avformat_license(void);
1973 
1974 /**
1975  * Initialize libavformat and register all the muxers, demuxers and
1976  * protocols. If you do not call this function, then you can select
1977  * exactly which formats you want to support.
1978  *
1979  * @see av_register_input_format()
1980  * @see av_register_output_format()
1981  */
1982 void av_register_all(void);
1983 
1986 
1987 /**
1988  * Do global initialization of network components. This is optional,
1989  * but recommended, since it avoids the overhead of implicitly
1990  * doing the setup for each session.
1991  *
1992  * Calling this function will become mandatory if using network
1993  * protocols at some major version bump.
1994  */
1995 int avformat_network_init(void);
1996 
1997 /**
1998  * Undo the initialization done by avformat_network_init.
1999  */
2000 int avformat_network_deinit(void);
2001 
2002 /**
2003  * If f is NULL, returns the first registered input format,
2004  * if f is non-NULL, returns the next registered input format after f
2005  * or NULL if f is the last one.
2006  */
2008 
2009 /**
2010  * If f is NULL, returns the first registered output format,
2011  * if f is non-NULL, returns the next registered output format after f
2012  * or NULL if f is the last one.
2013  */
2015 
2016 /**
2017  * Allocate an AVFormatContext.
2018  * avformat_free_context() can be used to free the context and everything
2019  * allocated by the framework within it.
2020  */
2022 
2023 /**
2024  * Free an AVFormatContext and all its streams.
2025  * @param s context to free
2026  */
2028 
2029 /**
2030  * Get the AVClass for AVFormatContext. It can be used in combination with
2031  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2032  *
2033  * @see av_opt_find().
2034  */
2035 const AVClass *avformat_get_class(void);
2036 
2037 /**
2038  * Add a new stream to a media file.
2039  *
2040  * When demuxing, it is called by the demuxer in read_header(). If the
2041  * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
2042  * be called in read_packet().
2043  *
2044  * When muxing, should be called by the user before avformat_write_header().
2045  *
2046  * User is required to call avcodec_close() and avformat_free_context() to
2047  * clean up the allocation by avformat_new_stream().
2048  *
2049  * @param s media file handle
2050  * @param c If non-NULL, the AVCodecContext corresponding to the new stream
2051  * will be initialized to use this codec. This is needed for e.g. codec-specific
2052  * defaults to be set, so codec should be provided if it is known.
2053  *
2054  * @return newly created stream or NULL on error.
2055  */
2057 
2058 /**
2059  * Wrap an existing array as stream side data.
2060  *
2061  * @param st stream
2062  * @param type side information type
2063  * @param data the side data array. It must be allocated with the av_malloc()
2064  * family of functions. The ownership of the data is transferred to
2065  * st.
2066  * @param size side information size
2067  * @return zero on success, a negative AVERROR code on failure. On failure,
2068  * the stream is unchanged and the data remains owned by the caller.
2069  */
2071  uint8_t *data, size_t size);
2072 
2073 /**
2074  * Allocate new information from stream.
2075  *
2076  * @param stream stream
2077  * @param type desired side information type
2078  * @param size side information size
2079  * @return pointer to fresh allocated data or NULL otherwise
2080  */
2082  enum AVPacketSideDataType type, int size);
2083 /**
2084  * Get side information from stream.
2085  *
2086  * @param stream stream
2087  * @param type desired side information type
2088  * @param size pointer for side information size to store (optional)
2089  * @return pointer to data if present or NULL otherwise
2090  */
2091 #if FF_API_NOCONST_GET_SIDE_DATA
2093  enum AVPacketSideDataType type, int *size);
2094 #else
2096  enum AVPacketSideDataType type, int *size);
2097 #endif
2098 
2100 
2101 /**
2102  * @}
2103  */
2104 
2105 
2106 /**
2107  * Allocate an AVFormatContext for an output format.
2108  * avformat_free_context() can be used to free the context and
2109  * everything allocated by the framework within it.
2110  *
2111  * @param *ctx is set to the created format context, or to NULL in
2112  * case of failure
2113  * @param oformat format to use for allocating the context, if NULL
2114  * format_name and filename are used instead
2115  * @param format_name the name of output format to use for allocating the
2116  * context, if NULL filename is used instead
2117  * @param filename the name of the filename to use for allocating the
2118  * context, may be NULL
2119  * @return >= 0 in case of success, a negative AVERROR code in case of
2120  * failure
2121  */
2123  const char *format_name, const char *filename);
2124 
2125 /**
2126  * @addtogroup lavf_decoding
2127  * @{
2128  */
2129 
2130 /**
2131  * Find AVInputFormat based on the short name of the input format.
2132  */
2133 AVInputFormat *av_find_input_format(const char *short_name);
2134 
2135 /**
2136  * Guess the file format.
2137  *
2138  * @param pd data to be probed
2139  * @param is_opened Whether the file is already opened; determines whether
2140  * demuxers with or without AVFMT_NOFILE are probed.
2141  */
2142 AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
2143 
2144 /**
2145  * Guess the file format.
2146  *
2147  * @param pd data to be probed
2148  * @param is_opened Whether the file is already opened; determines whether
2149  * demuxers with or without AVFMT_NOFILE are probed.
2150  * @param score_max A probe score larger that this is required to accept a
2151  * detection, the variable is set to the actual detection
2152  * score afterwards.
2153  * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
2154  * to retry with a larger probe buffer.
2155  */
2156 AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max);
2157 
2158 /**
2159  * Guess the file format.
2160  *
2161  * @param is_opened Whether the file is already opened; determines whether
2162  * demuxers with or without AVFMT_NOFILE are probed.
2163  * @param score_ret The score of the best detection.
2164  */
2165 AVInputFormat *av_probe_input_format3(AVProbeData *pd, int is_opened, int *score_ret);
2166 
2167 /**
2168  * Probe a bytestream to determine the input format. Each time a probe returns
2169  * with a score that is too low, the probe buffer size is increased and another
2170  * attempt is made. When the maximum probe size is reached, the input format
2171  * with the highest score is returned.
2172  *
2173  * @param pb the bytestream to probe
2174  * @param fmt the input format is put here
2175  * @param url the url of the stream
2176  * @param logctx the log context
2177  * @param offset the offset within the bytestream to probe from
2178  * @param max_probe_size the maximum probe buffer size (zero for default)
2179  * @return the score in case of success, a negative value corresponding to an
2180  * the maximal score is AVPROBE_SCORE_MAX
2181  * AVERROR code otherwise
2182  */
2184  const char *url, void *logctx,
2185  unsigned int offset, unsigned int max_probe_size);
2186 
2187 /**
2188  * Like av_probe_input_buffer2() but returns 0 on success
2189  */
2191  const char *url, void *logctx,
2192  unsigned int offset, unsigned int max_probe_size);
2193 
2194 /**
2195  * Open an input stream and read the header. The codecs are not opened.
2196  * The stream must be closed with avformat_close_input().
2197  *
2198  * @param ps Pointer to user-supplied AVFormatContext (allocated by avformat_alloc_context).
2199  * May be a pointer to NULL, in which case an AVFormatContext is allocated by this
2200  * function and written into ps.
2201  * Note that a user-supplied AVFormatContext will be freed on failure.
2202  * @param url URL of the stream to open.
2203  * @param fmt If non-NULL, this parameter forces a specific input format.
2204  * Otherwise the format is autodetected.
2205  * @param options A dictionary filled with AVFormatContext and demuxer-private options.
2206  * On return this parameter will be destroyed and replaced with a dict containing
2207  * options that were not found. May be NULL.
2208  *
2209  * @return 0 on success, a negative AVERROR on failure.
2210  *
2211  * @note If you want to use custom IO, preallocate the format context and set its pb field.
2212  */
2214 
2217 
2218 /**
2219  * Read packets of a media file to get stream information. This
2220  * is useful for file formats with no headers such as MPEG. This
2221  * function also computes the real framerate in case of MPEG-2 repeat
2222  * frame mode.
2223  * The logical file position is not changed by this function;
2224  * examined packets may be buffered for later processing.
2225  *
2226  * @param ic media file handle
2227  * @param options If non-NULL, an ic.nb_streams long array of pointers to
2228  * dictionaries, where i-th member contains options for
2229  * codec corresponding to i-th stream.
2230  * On return each dictionary will be filled with options that were not found.
2231  * @return >=0 if OK, AVERROR_xxx on error
2232  *
2233  * @note this function isn't guaranteed to open all the codecs, so
2234  * options being non-empty at return is a perfectly normal behavior.
2235  *
2236  * @todo Let the user decide somehow what information is needed so that
2237  * we do not waste time getting stuff the user does not need.
2238  */
2240 
2241 /**
2242  * Find the programs which belong to a given stream.
2243  *
2244  * @param ic media file handle
2245  * @param last the last found program, the search will start after this
2246  * program, or from the beginning if it is NULL
2247  * @param s stream index
2248  * @return the next program which belongs to s, NULL if no program is found or
2249  * the last program is not among the programs of ic.
2250  */
2252 
2253 void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx);
2254 
2255 /**
2256  * Find the "best" stream in the file.
2257  * The best stream is determined according to various heuristics as the most
2258  * likely to be what the user expects.
2259  * If the decoder parameter is non-NULL, av_find_best_stream will find the
2260  * default decoder for the stream's codec; streams for which no decoder can
2261  * be found are ignored.
2262  *
2263  * @param ic media file handle
2264  * @param type stream type: video, audio, subtitles, etc.
2265  * @param wanted_stream_nb user-requested stream number,
2266  * or -1 for automatic selection
2267  * @param related_stream try to find a stream related (eg. in the same
2268  * program) to this one, or -1 if none
2269  * @param decoder_ret if non-NULL, returns the decoder for the
2270  * selected stream
2271  * @param flags flags; none are currently defined
2272  * @return the non-negative stream number in case of success,
2273  * AVERROR_STREAM_NOT_FOUND if no stream with the requested type
2274  * could be found,
2275  * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
2276  * @note If av_find_best_stream returns successfully and decoder_ret is not
2277  * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
2278  */
2280  enum AVMediaType type,
2281  int wanted_stream_nb,
2282  int related_stream,
2283  AVCodec **decoder_ret,
2284  int flags);
2285 
2286 /**
2287  * Return the next frame of a stream.
2288  * This function returns what is stored in the file, and does not validate
2289  * that what is there are valid frames for the decoder. It will split what is
2290  * stored in the file into frames and return one for each call. It will not
2291  * omit invalid data between valid frames so as to give the decoder the maximum
2292  * information possible for decoding.
2293  *
2294  * If pkt->buf is NULL, then the packet is valid until the next
2295  * av_read_frame() or until avformat_close_input(). Otherwise the packet
2296  * is valid indefinitely. In both cases the packet must be freed with
2297  * av_packet_unref when it is no longer needed. For video, the packet contains
2298  * exactly one frame. For audio, it contains an integer number of frames if each
2299  * frame has a known fixed size (e.g. PCM or ADPCM data). If the audio frames
2300  * have a variable size (e.g. MPEG audio), then it contains one frame.
2301  *
2302  * pkt->pts, pkt->dts and pkt->duration are always set to correct
2303  * values in AVStream.time_base units (and guessed if the format cannot
2304  * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
2305  * has B-frames, so it is better to rely on pkt->dts if you do not
2306  * decompress the payload.
2307  *
2308  * @return 0 if OK, < 0 on error or end of file
2309  */
2311 
2312 /**
2313  * Seek to the keyframe at timestamp.
2314  * 'timestamp' in 'stream_index'.
2315  *
2316  * @param s media file handle
2317  * @param stream_index If stream_index is (-1), a default
2318  * stream is selected, and timestamp is automatically converted
2319  * from AV_TIME_BASE units to the stream specific time_base.
2320  * @param timestamp Timestamp in AVStream.time_base units
2321  * or, if no stream is specified, in AV_TIME_BASE units.
2322  * @param flags flags which select direction and seeking mode
2323  * @return >= 0 on success
2324  */
2325 int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
2326  int flags);
2327 
2328 /**
2329  * Seek to timestamp ts.
2330  * Seeking will be done so that the point from which all active streams
2331  * can be presented successfully will be closest to ts and within min/max_ts.
2332  * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
2333  *
2334  * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
2335  * are the file position (this may not be supported by all demuxers).
2336  * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
2337  * in the stream with stream_index (this may not be supported by all demuxers).
2338  * Otherwise all timestamps are in units of the stream selected by stream_index
2339  * or if stream_index is -1, in AV_TIME_BASE units.
2340  * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
2341  * keyframes (this may not be supported by all demuxers).
2342  * If flags contain AVSEEK_FLAG_BACKWARD, it is ignored.
2343  *
2344  * @param s media file handle
2345  * @param stream_index index of the stream which is used as time base reference
2346  * @param min_ts smallest acceptable timestamp
2347  * @param ts target timestamp
2348  * @param max_ts largest acceptable timestamp
2349  * @param flags flags
2350  * @return >=0 on success, error code otherwise
2351  *
2352  * @note This is part of the new seek API which is still under construction.
2353  * Thus do not use this yet. It may change at any time, do not expect
2354  * ABI compatibility yet!
2355  */
2356 int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
2357 
2358 /**
2359  * Discard all internally buffered data. This can be useful when dealing with
2360  * discontinuities in the byte stream. Generally works only with formats that
2361  * can resync. This includes headerless formats like MPEG-TS/TS but should also
2362  * work with NUT, Ogg and in a limited way AVI for example.
2363  *
2364  * The set of streams, the detected duration, stream parameters and codecs do
2365  * not change when calling this function. If you want a complete reset, it's
2366  * better to open a new AVFormatContext.
2367  *
2368  * This does not flush the AVIOContext (s->pb). If necessary, call
2369  * avio_flush(s->pb) before calling this function.
2370  *
2371  * @param s media file handle
2372  * @return >=0 on success, error code otherwise
2373  */
2375 
2376 /**
2377  * Start playing a network-based stream (e.g. RTSP stream) at the
2378  * current position.
2379  */
2381 
2382 /**
2383  * Pause a network-based stream (e.g. RTSP stream).
2384  *
2385  * Use av_read_play() to resume it.
2386  */
2388 
2389 /**
2390  * Close an opened input AVFormatContext. Free it and all its contents
2391  * and set *s to NULL.
2392  */
2394 /**
2395  * @}
2396  */
2397 
2398 #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
2399 #define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
2400 #define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
2401 #define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
2402 
2403 /**
2404  * @addtogroup lavf_encoding
2405  * @{
2406  */
2407 
2408 #define AVSTREAM_INIT_IN_WRITE_HEADER 0 ///< stream parameters initialized in avformat_write_header
2409 #define AVSTREAM_INIT_IN_INIT_OUTPUT 1 ///< stream parameters initialized in avformat_init_output
2411 /**
2412  * Allocate the stream private data and write the stream header to
2413  * an output media file.
2414  *
2415  * @param s Media file handle, must be allocated with avformat_alloc_context().
2416  * Its oformat field must be set to the desired output format;
2417  * Its pb field must be set to an already opened AVIOContext.
2418  * @param options An AVDictionary filled with AVFormatContext and muxer-private options.
2419  * On return this parameter will be destroyed and replaced with a dict containing
2420  * options that were not found. May be NULL.
2421  *
2422  * @return AVSTREAM_INIT_IN_WRITE_HEADER on success if the codec had not already been fully initialized in avformat_init,
2423  * AVSTREAM_INIT_IN_INIT_OUTPUT on success if the codec had already been fully initialized in avformat_init,
2424  * negative AVERROR on failure.
2425  *
2426  * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_init_output.
2427  */
2430 
2431 /**
2432  * Allocate the stream private data and initialize the codec, but do not write the header.
2433  * May optionally be used before avformat_write_header to initialize stream parameters
2434  * before actually writing the header.
2435  * If using this function, do not pass the same options to avformat_write_header.
2436  *
2437  * @param s Media file handle, must be allocated with avformat_alloc_context().
2438  * Its oformat field must be set to the desired output format;
2439  * Its pb field must be set to an already opened AVIOContext.
2440  * @param options An AVDictionary filled with AVFormatContext and muxer-private options.
2441  * On return this parameter will be destroyed and replaced with a dict containing
2442  * options that were not found. May be NULL.
2443  *
2444  * @return AVSTREAM_INIT_IN_WRITE_HEADER on success if the codec requires avformat_write_header to fully initialize,
2445  * AVSTREAM_INIT_IN_INIT_OUTPUT on success if the codec has been fully initialized,
2446  * negative AVERROR on failure.
2447  *
2448  * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_write_header.
2449  */
2452 
2453 /**
2454  * Write a packet to an output media file.
2455  *
2456  * This function passes the packet directly to the muxer, without any buffering
2457  * or reordering. The caller is responsible for correctly interleaving the
2458  * packets if the format requires it. Callers that want libavformat to handle
2459  * the interleaving should call av_interleaved_write_frame() instead of this
2460  * function.
2461  *
2462  * @param s media file handle
2463  * @param pkt The packet containing the data to be written. Note that unlike
2464  * av_interleaved_write_frame(), this function does not take
2465  * ownership of the packet passed to it (though some muxers may make
2466  * an internal reference to the input packet).
2467  * <br>
2468  * This parameter can be NULL (at any time, not just at the end), in
2469  * order to immediately flush data buffered within the muxer, for
2470  * muxers that buffer up data internally before writing it to the
2471  * output.
2472  * <br>
2473  * Packet's @ref AVPacket.stream_index "stream_index" field must be
2474  * set to the index of the corresponding stream in @ref
2475  * AVFormatContext.streams "s->streams".
2476  * <br>
2477  * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2478  * must be set to correct values in the stream's timebase (unless the
2479  * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2480  * they can be set to AV_NOPTS_VALUE).
2481  * The dts for subsequent packets passed to this function must be strictly
2482  * increasing when compared in their respective timebases (unless the
2483  * output format is flagged with the AVFMT_TS_NONSTRICT, then they
2484  * merely have to be nondecreasing). @ref AVPacket.duration
2485  * "duration") should also be set if known.
2486  * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush
2487  *
2488  * @see av_interleaved_write_frame()
2489  */
2491 
2492 /**
2493  * Write a packet to an output media file ensuring correct interleaving.
2494  *
2495  * This function will buffer the packets internally as needed to make sure the
2496  * packets in the output file are properly interleaved in the order of
2497  * increasing dts. Callers doing their own interleaving should call
2498  * av_write_frame() instead of this function.
2499  *
2500  * Using this function instead of av_write_frame() can give muxers advance
2501  * knowledge of future packets, improving e.g. the behaviour of the mp4
2502  * muxer for VFR content in fragmenting mode.
2503  *
2504  * @param s media file handle
2505  * @param pkt The packet containing the data to be written.
2506  * <br>
2507  * If the packet is reference-counted, this function will take
2508  * ownership of this reference and unreference it later when it sees
2509  * fit.
2510  * The caller must not access the data through this reference after
2511  * this function returns. If the packet is not reference-counted,
2512  * libavformat will make a copy.
2513  * <br>
2514  * This parameter can be NULL (at any time, not just at the end), to
2515  * flush the interleaving queues.
2516  * <br>
2517  * Packet's @ref AVPacket.stream_index "stream_index" field must be
2518  * set to the index of the corresponding stream in @ref
2519  * AVFormatContext.streams "s->streams".
2520  * <br>
2521  * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2522  * must be set to correct values in the stream's timebase (unless the
2523  * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2524  * they can be set to AV_NOPTS_VALUE).
2525  * The dts for subsequent packets in one stream must be strictly
2526  * increasing (unless the output format is flagged with the
2527  * AVFMT_TS_NONSTRICT, then they merely have to be nondecreasing).
2528  * @ref AVPacket.duration "duration") should also be set if known.
2529  *
2530  * @return 0 on success, a negative AVERROR on error. Libavformat will always
2531  * take care of freeing the packet, even if this function fails.
2532  *
2533  * @see av_write_frame(), AVFormatContext.max_interleave_delta
2534  */
2536 
2537 /**
2538  * Write an uncoded frame to an output media file.
2539  *
2540  * The frame must be correctly interleaved according to the container
2541  * specification; if not, then av_interleaved_write_frame() must be used.
2542  *
2543  * See av_interleaved_write_frame() for details.
2544  */
2545 int av_write_uncoded_frame(AVFormatContext *s, int stream_index,
2546  AVFrame *frame);
2547 
2548 /**
2549  * Write an uncoded frame to an output media file.
2550  *
2551  * If the muxer supports it, this function makes it possible to write an AVFrame
2552  * structure directly, without encoding it into a packet.
2553  * It is mostly useful for devices and similar special muxers that use raw
2554  * video or PCM data and will not serialize it into a byte stream.
2555  *
2556  * To test whether it is possible to use it with a given muxer and stream,
2557  * use av_write_uncoded_frame_query().
2558  *
2559  * The caller gives up ownership of the frame and must not access it
2560  * afterwards.
2561  *
2562  * @return >=0 for success, a negative code on error
2563  */
2564 int av_interleaved_write_uncoded_frame(AVFormatContext *s, int stream_index,
2565  AVFrame *frame);
2566 
2567 /**
2568  * Test whether a muxer supports uncoded frame.
2569  *
2570  * @return >=0 if an uncoded frame can be written to that muxer and stream,
2571  * <0 if not
2572  */
2573 int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index);
2574 
2575 /**
2576  * Write the stream trailer to an output media file and free the
2577  * file private data.
2578  *
2579  * May only be called after a successful call to avformat_write_header.
2580  *
2581  * @param s media file handle
2582  * @return 0 if OK, AVERROR_xxx on error
2583  */
2585 
2586 /**
2587  * Return the output format in the list of registered output formats
2588  * which best matches the provided parameters, or return NULL if
2589  * there is no match.
2590  *
2591  * @param short_name if non-NULL checks if short_name matches with the
2592  * names of the registered formats
2593  * @param filename if non-NULL checks if filename terminates with the
2594  * extensions of the registered formats
2595  * @param mime_type if non-NULL checks if mime_type matches with the
2596  * MIME type of the registered formats
2597  */
2598 AVOutputFormat *av_guess_format(const char *short_name,
2599  const char *filename,
2600  const char *mime_type);
2601 
2602 /**
2603  * Guess the codec ID based upon muxer and filename.
2604  */
2605 enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
2606  const char *filename, const char *mime_type,
2607  enum AVMediaType type);
2608 
2609 /**
2610  * Get timing information for the data currently output.
2611  * The exact meaning of "currently output" depends on the format.
2612  * It is mostly relevant for devices that have an internal buffer and/or
2613  * work in real time.
2614  * @param s media file handle
2615  * @param stream stream in the media file
2616  * @param[out] dts DTS of the last packet output for the stream, in stream
2617  * time_base units
2618  * @param[out] wall absolute time when that packet whas output,
2619  * in microsecond
2620  * @return 0 if OK, AVERROR(ENOSYS) if the format does not support it
2621  * Note: some formats or devices may not allow to measure dts and wall
2622  * atomically.
2623  */
2624 int av_get_output_timestamp(struct AVFormatContext *s, int stream,
2625  int64_t *dts, int64_t *wall);
2626 
2627 
2628 /**
2629  * @}
2630  */
2631 
2632 
2633 /**
2634  * @defgroup lavf_misc Utility functions
2635  * @ingroup libavf
2636  * @{
2637  *
2638  * Miscellaneous utility functions related to both muxing and demuxing
2639  * (or neither).
2640  */
2641 
2642 /**
2643  * Send a nice hexadecimal dump of a buffer to the specified file stream.
2644  *
2645  * @param f The file stream pointer where the dump should be sent to.
2646  * @param buf buffer
2647  * @param size buffer size
2648  *
2649  * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2
2650  */
2651 void av_hex_dump(FILE *f, const uint8_t *buf, int size);
2652 
2653 /**
2654  * Send a nice hexadecimal dump of a buffer to the log.
2655  *
2656  * @param avcl A pointer to an arbitrary struct of which the first field is a
2657  * pointer to an AVClass struct.
2658  * @param level The importance level of the message, lower values signifying
2659  * higher importance.
2660  * @param buf buffer
2661  * @param size buffer size
2662  *
2663  * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2
2664  */
2665 void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size);
2666 
2667 /**
2668  * Send a nice dump of a packet to the specified file stream.
2669  *
2670  * @param f The file stream pointer where the dump should be sent to.
2671  * @param pkt packet to dump
2672  * @param dump_payload True if the payload must be displayed, too.
2673  * @param st AVStream that the packet belongs to
2674  */
2675 void av_pkt_dump2(FILE *f, const AVPacket *pkt, int dump_payload, const AVStream *st);
2676 
2677 
2678 /**
2679  * Send a nice dump of a packet to the log.
2680  *
2681  * @param avcl A pointer to an arbitrary struct of which the first field is a
2682  * pointer to an AVClass struct.
2683  * @param level The importance level of the message, lower values signifying
2684  * higher importance.
2685  * @param pkt packet to dump
2686  * @param dump_payload True if the payload must be displayed, too.
2687  * @param st AVStream that the packet belongs to
2688  */
2689 void av_pkt_dump_log2(void *avcl, int level, const AVPacket *pkt, int dump_payload,
2690  const AVStream *st);
2691 
2692 /**
2693  * Get the AVCodecID for the given codec tag tag.
2694  * If no codec id is found returns AV_CODEC_ID_NONE.
2695  *
2696  * @param tags list of supported codec_id-codec_tag pairs, as stored
2697  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2698  * @param tag codec tag to match to a codec ID
2699  */
2700 enum AVCodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
2701 
2702 /**
2703  * Get the codec tag for the given codec id id.
2704  * If no codec tag is found returns 0.
2705  *
2706  * @param tags list of supported codec_id-codec_tag pairs, as stored
2707  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2708  * @param id codec ID to match to a codec tag
2709  */
2710 unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id);
2711 
2712 /**
2713  * Get the codec tag for the given codec id.
2714  *
2715  * @param tags list of supported codec_id - codec_tag pairs, as stored
2716  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2717  * @param id codec id that should be searched for in the list
2718  * @param tag A pointer to the found tag
2719  * @return 0 if id was not found in tags, > 0 if it was found
2720  */
2721 int av_codec_get_tag2(const struct AVCodecTag * const *tags, enum AVCodecID id,
2722  unsigned int *tag);
2723 
2725 
2726 /**
2727  * Get the index for a specific timestamp.
2728  *
2729  * @param st stream that the timestamp belongs to
2730  * @param timestamp timestamp to retrieve the index for
2731  * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
2732  * to the timestamp which is <= the requested one, if backward
2733  * is 0, then it will be >=
2734  * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
2735  * @return < 0 if no such timestamp could be found
2736  */
2737 int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
2738 
2739 /**
2740  * Add an index entry into a sorted list. Update the entry if the list
2741  * already contains it.
2742  *
2743  * @param timestamp timestamp in the time base of the given stream
2744  */
2745 int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
2746  int size, int distance, int flags);
2747 
2748 
2749 /**
2750  * Split a URL string into components.
2751  *
2752  * The pointers to buffers for storing individual components may be null,
2753  * in order to ignore that component. Buffers for components not found are
2754  * set to empty strings. If the port is not found, it is set to a negative
2755  * value.
2756  *
2757  * @param proto the buffer for the protocol
2758  * @param proto_size the size of the proto buffer
2759  * @param authorization the buffer for the authorization
2760  * @param authorization_size the size of the authorization buffer
2761  * @param hostname the buffer for the host name
2762  * @param hostname_size the size of the hostname buffer
2763  * @param port_ptr a pointer to store the port number in
2764  * @param path the buffer for the path
2765  * @param path_size the size of the path buffer
2766  * @param url the URL to split
2767  */
2768 void av_url_split(char *proto, int proto_size,
2769  char *authorization, int authorization_size,
2770  char *hostname, int hostname_size,
2771  int *port_ptr,
2772  char *path, int path_size,
2773  const char *url);
2774 
2775 
2776 /**
2777  * Print detailed information about the input or output format, such as
2778  * duration, bitrate, streams, container, programs, metadata, side data,
2779  * codec and time base.
2780  *
2781  * @param ic the context to analyze
2782  * @param index index of the stream to dump information about
2783  * @param url the URL to print, such as source or destination file
2784  * @param is_output Select whether the specified context is an input(0) or output(1)
2785  */
2787  int index,
2788  const char *url,
2789  int is_output);
2790 
2791 
2792 #define AV_FRAME_FILENAME_FLAGS_MULTIPLE 1 ///< Allow multiple %d
2793 
2794 /**
2795  * Return in 'buf' the path with '%d' replaced by a number.
2796  *
2797  * Also handles the '%0nd' format where 'n' is the total number
2798  * of digits and '%%'.
2799  *
2800  * @param buf destination buffer
2801  * @param buf_size destination buffer size
2802  * @param path numbered sequence string
2803  * @param number frame number
2804  * @param flags AV_FRAME_FILENAME_FLAGS_*
2805  * @return 0 if OK, -1 on format error
2806  */
2807 int av_get_frame_filename2(char *buf, int buf_size,
2808  const char *path, int number, int flags);
2809 
2810 int av_get_frame_filename(char *buf, int buf_size,
2811  const char *path, int number);
2812 
2813 /**
2814  * Check whether filename actually is a numbered sequence generator.
2815  *
2816  * @param filename possible numbered sequence string
2817  * @return 1 if a valid numbered sequence string, 0 otherwise
2818  */
2819 int av_filename_number_test(const char *filename);
2820 
2821 /**
2822  * Generate an SDP for an RTP session.
2823  *
2824  * Note, this overwrites the id values of AVStreams in the muxer contexts
2825  * for getting unique dynamic payload types.
2826  *
2827  * @param ac array of AVFormatContexts describing the RTP streams. If the
2828  * array is composed by only one context, such context can contain
2829  * multiple AVStreams (one AVStream per RTP stream). Otherwise,
2830  * all the contexts in the array (an AVCodecContext per RTP stream)
2831  * must contain only one AVStream.
2832  * @param n_files number of AVCodecContexts contained in ac
2833  * @param buf buffer where the SDP will be stored (must be allocated by
2834  * the caller)
2835  * @param size the size of the buffer
2836  * @return 0 if OK, AVERROR_xxx on error
2837  */
2838 int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size);
2839 
2840 /**
2841  * Return a positive value if the given filename has one of the given
2842  * extensions, 0 otherwise.
2843  *
2844  * @param filename file name to check against the given extensions
2845  * @param extensions a comma-separated list of filename extensions
2846  */
2847 int av_match_ext(const char *filename, const char *extensions);
2848 
2849 /**
2850  * Test if the given container can store a codec.
2851  *
2852  * @param ofmt container to check for compatibility
2853  * @param codec_id codec to potentially store in container
2854  * @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
2855  *
2856  * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
2857  * A negative number if this information is not available.
2858  */
2860  int std_compliance);
2861 
2862 /**
2863  * @defgroup riff_fourcc RIFF FourCCs
2864  * @{
2865  * Get the tables mapping RIFF FourCCs to libavcodec AVCodecIDs. The tables are
2866  * meant to be passed to av_codec_get_id()/av_codec_get_tag() as in the
2867  * following code:
2868  * @code
2869  * uint32_t tag = MKTAG('H', '2', '6', '4');
2870  * const struct AVCodecTag *table[] = { avformat_get_riff_video_tags(), 0 };
2871  * enum AVCodecID id = av_codec_get_id(table, tag);
2872  * @endcode
2873  */
2874 /**
2875  * @return the table mapping RIFF FourCCs for video to libavcodec AVCodecID.
2876  */
2877 const struct AVCodecTag *avformat_get_riff_video_tags(void);
2878 /**
2879  * @return the table mapping RIFF FourCCs for audio to AVCodecID.
2880  */
2881 const struct AVCodecTag *avformat_get_riff_audio_tags(void);
2882 /**
2883  * @return the table mapping MOV FourCCs for video to libavcodec AVCodecID.
2884  */
2885 const struct AVCodecTag *avformat_get_mov_video_tags(void);
2886 /**
2887  * @return the table mapping MOV FourCCs for audio to AVCodecID.
2888  */
2889 const struct AVCodecTag *avformat_get_mov_audio_tags(void);
2890 
2891 /**
2892  * @}
2893  */
2894 
2895 /**
2896  * Guess the sample aspect ratio of a frame, based on both the stream and the
2897  * frame aspect ratio.
2898  *
2899  * Since the frame aspect ratio is set by the codec but the stream aspect ratio
2900  * is set by the demuxer, these two may not be equal. This function tries to
2901  * return the value that you should use if you would like to display the frame.
2902  *
2903  * Basic logic is to use the stream aspect ratio if it is set to something sane
2904  * otherwise use the frame aspect ratio. This way a container setting, which is
2905  * usually easy to modify can override the coded value in the frames.
2906  *
2907  * @param format the format context which the stream is part of
2908  * @param stream the stream which the frame is part of
2909  * @param frame the frame with the aspect ratio to be determined
2910  * @return the guessed (valid) sample_aspect_ratio, 0/1 if no idea
2911  */
2913 
2914 /**
2915  * Guess the frame rate, based on both the container and codec information.
2916  *
2917  * @param ctx the format context which the stream is part of
2918  * @param stream the stream which the frame is part of
2919  * @param frame the frame for which the frame rate should be determined, may be NULL
2920  * @return the guessed (valid) frame rate, 0/1 if no idea
2921  */
2923 
2924 /**
2925  * Check if the stream st contained in s is matched by the stream specifier
2926  * spec.
2927  *
2928  * See the "stream specifiers" chapter in the documentation for the syntax
2929  * of spec.
2930  *
2931  * @return >0 if st is matched by spec;
2932  * 0 if st is not matched by spec;
2933  * AVERROR code if spec is invalid
2934  *
2935  * @note A stream specifier can match several streams in the format.
2936  */
2938  const char *spec);
2939 
2941 
2942 /**
2943  * Apply a list of bitstream filters to a packet.
2944  *
2945  * @param codec AVCodecContext, usually from an AVStream
2946  * @param pkt the packet to apply filters to. If, on success, the returned
2947  * packet has size == 0 and side_data_elems == 0, it indicates that
2948  * the packet should be dropped
2949  * @param bsfc a NULL-terminated list of filters to apply
2950  * @return >=0 on success;
2951  * AVERROR code on failure
2952  */
2953 #if FF_API_OLD_BSF
2955 int av_apply_bitstream_filters(AVCodecContext *codec, AVPacket *pkt,
2956  AVBitStreamFilterContext *bsfc);
2957 #endif
2958 
2959 enum AVTimebaseSource {
2960  AVFMT_TBCF_AUTO = -1,
2963 #if FF_API_R_FRAME_RATE
2964  AVFMT_TBCF_R_FRAMERATE,
2965 #endif
2966 };
2967 
2968 /**
2969  * Transfer internal timing information from one stream to another.
2970  *
2971  * This function is useful when doing stream copy.
2972  *
2973  * @param ofmt target output format for ost
2974  * @param ost output stream which needs timings copy and adjustments
2975  * @param ist reference input stream to copy timings from
2976  * @param copy_tb define from where the stream codec timebase needs to be imported
2977  */
2979  AVStream *ost, const AVStream *ist,
2980  enum AVTimebaseSource copy_tb);
2981 
2982 /**
2983  * Get the internal codec timebase from a stream.
2984  *
2985  * @param st input stream to extract the timebase from
2986  */
2988 
2989 /**
2990  * @}
2991  */
2992 
2993 #endif /* AVFORMAT_AVFORMAT_H */
unsigned int nb_chapters
Number of chapters in AVChapter array.
Definition: avformat.h:1543
unsigned int max_index_size
Maximum amount of memory in bytes to use for the index of each stream.
Definition: avformat.h:1524
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:4461
int64_t interleaver_chunk_size
Definition: avformat.h:1112
int64_t probesize
Maximum size of the data read from input for determining the input container format.
Definition: avformat.h:1480
unsigned int packet_size
Definition: avformat.h:1442
int64_t first_dts
Timestamp corresponding to the last dts sync point.
Definition: avformat.h:1060
full parsing and interpolation of timestamps for frames not starting on a packet boundary ...
Definition: avformat.h:812
const char const char void * val
Definition: avisynth_c.h:771
int64_t duration_gcd
Definition: avformat.h:1024
int audio_preload
Audio preload in microseconds.
Definition: avformat.h:1662
const char * s
Definition: avisynth_c.h:768
Bytestream IO Context.
Definition: avio.h:147
enum AVCodecID codec_id
Definition: ffmpeg_vaapi.c:149
void av_pkt_dump2(FILE *f, const AVPacket *pkt, int dump_payload, const AVStream *st)
Send a nice dump of a packet to the specified file stream.
Definition: dump.c:108
AVProbeData probe_data
Definition: avformat.h:1083
Buffered I/O operations.
AVPacketSideDataType
Definition: avcodec.h:1362
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:1567
attribute_deprecated int av_demuxer_open(AVFormatContext *ic)
Definition: utils.c:372
char * recommended_encoder_configuration
String containing paris of key and values describing recommended encoder configuration.
Definition: avformat.h:1215
This structure describes decoded (raw) audio or video data.
Definition: frame.h:190
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:763
AVCodec * av_format_get_video_codec(const AVFormatContext *s)
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file ensuring correct interleaving.
Definition: mux.c:1232
AVIOInterruptCB interrupt_callback
Custom interrupt callbacks for the I/O layer.
Definition: avformat.h:1592
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
static void flush(AVCodecContext *avctx)
int(* init)(struct AVFormatContext *)
Initialize format.
Definition: avformat.h:634
int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp, int size, int distance, int flags)
Add an index entry into a sorted list.
Definition: utils.c:1957
int flush_packets
Flush the I/O context after each packet.
Definition: avformat.h:1729
enum AVCodecID id
Definition: mxfenc.c:104
int av_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file.
Definition: mux.c:919
const char * fmt
Definition: avisynth_c.h:769
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:1701
int64_t start_skip_samples
If not 0, the number of samples that should be skipped from the start of the stream (the samples are ...
Definition: avformat.h:1141
void(* deinit)(struct AVFormatContext *)
Deinitialize format.
Definition: avformat.h:643
const char * filename
Definition: avformat.h:462
int64_t pts_buffer[MAX_REORDER_DELAY+1]
Definition: avformat.h:1085
unsigned int max_picture_buffer
Maximum amount of memory in bytes to use for buffering frames obtained from realtime capture devices...
Definition: avformat.h:1530
int64_t pos
Definition: avformat.h:820
int probe_packets
Number of packets to buffer for codec probing.
Definition: avformat.h:1068
int event_flags
Flags for the user to detect events happening on the stream.
Definition: avformat.h:1007
struct FFFrac * priv_pts
Definition: avformat.h:1224
AVRational av_guess_sample_aspect_ratio(AVFormatContext *format, AVStream *stream, AVFrame *frame)
Guess the sample aspect ratio of a frame, based on both the stream and the frame aspect ratio...
Definition: utils.c:4757
enum AVCodecID video_codec
default video codec
Definition: avformat.h:535
int64_t first_discard_sample
If not 0, the first audio sample that should be discarded from the stream.
Definition: avformat.h:1149
void av_stream_set_r_frame_rate(AVStream *s, AVRational r)
int64_t pts_wrap_reference
Internal data to check for wrapping of the time stamp.
Definition: avformat.h:1173
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:956
uint8_t * dump_separator
dump format separator.
Definition: avformat.h:1841
int index
stream index in AVFormatContext
Definition: avformat.h:890
int avio_flags
avio flags, used to force AVIO_FLAG_DIRECT.
Definition: avformat.h:1693
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1087
int(* check_bitstream)(struct AVFormatContext *, const AVPacket *pkt)
Set up any necessary bitstream filtering and extract any extra data needed for the global header...
Definition: avformat.h:649
int(* free_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps)
Free device capabilities submodule.
Definition: avformat.h:623
int64_t bit_rate
Total stream bitrate in bit/s, 0 if not available.
Definition: avformat.h:1440
int event_flags
Flags for the user to detect events happening on the file.
Definition: avformat.h:1629
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:1356
void * priv_data
Definition: avformat.h:904
AVInputFormat * av_probe_input_format3(AVProbeData *pd, int is_opened, int *score_ret)
Guess the file format.
Definition: format.c:173
int(* write_packet)(struct AVFormatContext *, AVPacket *pkt)
Write a packet.
Definition: avformat.h:575
AVPacketSideData * side_data
An array of side data that applies to the whole stream (i.e.
Definition: avformat.h:996
static AVPacket pkt
int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index)
Test whether a muxer supports uncoded frame.
Definition: mux.c:1433
int priv_data_size
Size of private data so that it can be allocated in the wrapper.
Definition: avformat.h:715
int ctx_flags
Flags signalling stream properties.
Definition: avformat.h:1387
AVDictionary * metadata
Definition: avformat.h:1299
enum AVCodecID subtitle_codec_id
Forced subtitle codec_id.
Definition: avformat.h:1512
AVCodec.
Definition: avcodec.h:3607
int strict_std_compliance
Allow non-standard and experimental extension.
Definition: avformat.h:1622
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3979
void av_format_set_subtitle_codec(AVFormatContext *s, AVCodec *c)
enum AVDurationEstimationMethod av_fmt_ctx_get_duration_estimation_method(const AVFormatContext *ctx)
Returns the method used to set ctx->duration.
Definition: options.c:151
int64_t last_dts_for_order_check
Internal data to analyze DTS and detect faulty mpeg streams.
Definition: avformat.h:1201
Format I/O context.
Definition: avformat.h:1338
int64_t output_ts_offset
Output timestamp offset, in microseconds.
Definition: avformat.h:1831
AVRational av_guess_frame_rate(AVFormatContext *ctx, AVStream *stream, AVFrame *frame)
Guess the frame rate, based on both the container and codec information.
Definition: utils.c:4780
unsigned int nb_stream_indexes
Definition: avformat.h:1270
int64_t cur_dts
Definition: avformat.h:1061
const struct AVCodecTag * avformat_get_mov_audio_tags(void)
Definition: isom.c:637
Public dictionary API.
int flags
Definition: avformat.h:1267
int(* read_close)(struct AVFormatContext *)
Close the stream.
Definition: avformat.h:746
int flags
can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS, AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH, AVFMT_TS_NONSTRICT, AVFMT_TS_NEGATIVE
Definition: avformat.h:543
uint8_t
int stream_identifier
Stream Identifier This is the MPEG-TS stream identifier +1 0 means unknown.
Definition: avformat.h:1110
const struct AVCodecTag * avformat_get_riff_video_tags(void)
Definition: riff.c:537
int flags
Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS, AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH, AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK, AVFMT_SEEK_TO_PTS.
Definition: avformat.h:678
enum AVCodecID av_codec_get_id(const struct AVCodecTag *const *tags, unsigned int tag)
Get the AVCodecID for the given codec tag tag.
unsigned avformat_version(void)
Return the LIBAVFORMAT_VERSION_INT constant.
Definition: utils.c:63
const char * avformat_license(void)
Return the libavformat license.
Definition: utils.c:74
int 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: utils.c:5374
int(* free_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps)
Free device capabilities submodule.
Definition: avformat.h:802
AVPacket pkt
Definition: avformat.h:1955
int priv_data_size
size of private data so that it can be allocated in the wrapper
Definition: avformat.h:565
The exact value of the fractional number is: 'val + num / den'.
Definition: internal.h:61
int id
unique ID to identify the chapter
Definition: avformat.h:1296
enum AVStreamParseType need_parsing
Definition: avformat.h:1076
int id
Format-specific stream ID.
Definition: avformat.h:896
int avformat_match_stream_specifier(AVFormatContext *s, AVStream *st, const char *spec)
Check if the stream st contained in s is matched by the stream specifier spec.
Definition: utils.c:4801
int duration_count
Definition: avformat.h:1025
int nb_side_data
The number of elements in the AVStream.side_data array.
Definition: avformat.h:1000
AVDurationEstimationMethod
The duration of a video can be estimated through various ways, and this enum can be used to know how ...
Definition: avformat.h:1316
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4214
int pmt_pid
Definition: avformat.h:1274
uint8_t * av_stream_get_side_data(const AVStream *stream, enum AVPacketSideDataType type, int *size)
Get side information from stream.
Definition: utils.c:5098
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1406
int av_codec_get_tag2(const struct AVCodecTag *const *tags, enum AVCodecID id, unsigned int *tag)
Get the codec tag for the given codec id.
static AVFrame * frame
AVFormatContext * avformat_alloc_context(void)
Allocate an AVFormatContext.
Definition: options.c:132
int inject_global_side_data
Internal data to inject global side data.
Definition: avformat.h:1208
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:113
const char * avformat_configuration(void)
Return the libavformat build-time configuration.
Definition: utils.c:69
#define MAX_REORDER_DELAY
Definition: avformat.h:1084
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:689
int64_t last_duration
Definition: avformat.h:1038
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1449
AVProgram * av_new_program(AVFormatContext *s, int id)
Definition: utils.c:4310
char * protocol_whitelist
',' separated list of allowed protocols.
Definition: avformat.h:1876
int(* read_header)(struct AVFormatContext *)
Read the format header and initialize the AVFormatContext structure.
Definition: avformat.h:729
int64_t max_interleave_delta
Maximum buffering duration for interleaving.
Definition: avformat.h:1616
static int flags
Definition: log.c:57
uint32_t tag
Definition: movenc.c:1412
int avformat_network_init(void)
Do global initialization of network components.
Definition: utils.c:4692
const struct AVCodecTag * avformat_get_riff_audio_tags(void)
Definition: riff.c:542
int fps_probe_size
The number of frames used for determining the framerate in avformat_find_stream_info().
Definition: avformat.h:1574
int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size)
Generate an SDP for an RTP session.
Definition: sdp.c:827
struct AVStream::@190 * info
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:289
int av_match_ext(const char *filename, const char *extensions)
Return a positive value if the given filename has one of the given extensions, 0 otherwise.
Definition: format.c:85
const AVClass * avformat_get_class(void)
Get the AVClass for AVFormatContext.
Definition: options.c:156
ptrdiff_t size
Definition: opengl_enc.c:101
int av_probe_input_buffer2(AVIOContext *pb, AVInputFormat **fmt, const char *url, void *logctx, unsigned int offset, unsigned int max_probe_size)
Probe a bytestream to determine the input format.
Definition: format.c:266
enum AVDiscard discard
selects which program to discard and which to feed to the caller
Definition: avformat.h:1268
const OptionDef options[]
Definition: ffserver.c:3950
unsigned int * stream_index
Definition: avformat.h:1269
AVCodec * av_format_get_audio_codec(const AVFormatContext *s)
enum AVCodecID video_codec_id
Forced video codec_id.
Definition: avformat.h:1500
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:814
int64_t rfps_duration_sum
Definition: avformat.h:1026
Duration estimated from bitrate (less accurate)
Definition: avformat.h:1319
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:299
unsigned int correct_ts_overflow
Correct single timestamp overflows.
Definition: avformat.h:1715
struct AVOutputFormat * oformat
The output container format.
Definition: avformat.h:1357
int64_t start_time
Definition: avformat.h:1284
const struct AVCodecTag * avformat_get_mov_video_tags(void)
Definition: isom.c:632
int avformat_alloc_output_context2(AVFormatContext **ctx, AVOutputFormat *oformat, const char *format_name, const char *filename)
Allocate an AVFormatContext for an output format.
Definition: mux.c:148
void av_dump_format(AVFormatContext *ic, int index, const char *url, int is_output)
Print detailed information about the input or output format, such as duration, bitrate, streams, container, programs, metadata, side data, codec and time base.
Definition: dump.c:541
Callback for checking whether to abort blocking functions.
Definition: avio.h:50
int av_find_best_stream(AVFormatContext *ic, enum AVMediaType type, int wanted_stream_nb, int related_stream, AVCodec **decoder_ret, int flags)
Find the "best" stream in the file.
Definition: utils.c:3955
AVRational av_stream_get_codec_timebase(const AVStream *st)
Get the internal codec timebase from a stream.
Definition: utils.c:5436
int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt, const char *url, void *logctx, unsigned int offset, unsigned int max_probe_size)
Like av_probe_input_buffer2() but returns 0 on success.
Definition: format.c:364
int(* write_uncoded_frame)(struct AVFormatContext *, int stream_index, AVFrame **frame, unsigned flags)
Write an uncoded AVFrame.
Definition: avformat.h:607
AVProgram * av_find_program_from_stream(AVFormatContext *ic, AVProgram *last, int s)
Find the programs which belong to a given stream.
Definition: utils.c:3938
int max_ts_probe
Maximum number of packets to read while waiting for the first timestamp.
Definition: avformat.h:1636
int format_probesize
number of bytes to read maximally to identify format.
Definition: avformat.h:1745
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:191
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1554
int nb_decoded_frames
Number of internally decoded frames, used internally in libavformat, do not access its lifetime diffe...
Definition: avformat.h:1162
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2066
const AVIOInterruptCB int_cb
Definition: ffmpeg.c:460
int(* read_probe)(AVProbeData *)
Tell if a given file has a chance of being parsed as this format.
Definition: avformat.h:722
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:74
int64_t pts_wrap_reference
reference dts for wrap detection
Definition: avformat.h:1287
const char * long_name
Descriptive name for the format, meant to be more human-readable than name.
Definition: avformat.h:530
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:821
void av_format_set_data_codec(AVFormatContext *s, AVCodec *c)
int(* query_codec)(enum AVCodecID id, int std_compliance)
Test if the given codec can be stored in this container.
Definition: avformat.h:589
AVCodec * av_format_get_subtitle_codec(const AVFormatContext *s)
int(* write_header)(struct AVFormatContext *)
Definition: avformat.h:567
const char * r
Definition: vf_curves.c:111
struct AVCodecParserContext * av_stream_get_parser(const AVStream *s)
Definition: utils.c:130
unsigned int nb_programs
Definition: avformat.h:1493
int last_IP_duration
Definition: avformat.h:1063
int av_read_play(AVFormatContext *s)
Start playing a network-based stream (e.g.
Definition: utils.c:4019
AVChapter ** chapters
Definition: avformat.h:1544
int skip_samples
Number of samples to skip at the start of the frame decoded from the next packet. ...
Definition: avformat.h:1132
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:967
New fields can be added to the end with minor version bumps.
Definition: avformat.h:1265
AVInputFormat * av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max)
Guess the file format.
Definition: format.c:249
int min_distance
Minimum distance between this and the previous keyframe, used to avoid unneeded searching.
Definition: avformat.h:833
int program_num
Definition: avformat.h:1273
AVCodec * audio_codec
Forced audio codec.
Definition: avformat.h:1791
void * opaque
User data.
Definition: avformat.h:1820
Only parse headers, do not repack.
Definition: avformat.h:811
char * format_whitelist
',' separated list of allowed demuxers.
Definition: avformat.h:1761
int avformat_query_codec(const AVOutputFormat *ofmt, enum AVCodecID codec_id, int std_compliance)
Test if the given container can store a codec.
Definition: utils.c:4674
static float distance(float x, float y, int band)
const char * mime_type
mime_type, when known.
Definition: avformat.h:465
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:464
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:463
void av_format_inject_global_side_data(AVFormatContext *s)
This function will cause global side data to be injected in the next packet of each stream as well as...
Definition: utils.c:135
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1394
void av_stream_set_recommended_encoder_configuration(AVStream *s, char *configuration)
int64_t fps_first_dts
Those are used for average framerate estimation.
Definition: avformat.h:1043
int av_read_pause(AVFormatContext *s)
Pause a network-based stream (e.g.
Definition: utils.c:4028
AVInputFormat * av_find_input_format(const char *short_name)
Find AVInputFormat based on the short name of the input format.
Definition: format.c:164
static void callback(void *priv_data, int index, uint8_t *buf, int buf_size, int64_t time, enum dshowDeviceType devtype)
Definition: dshow.c:161
char filename[1024]
input or output filename
Definition: avformat.h:1414
int update_initial_durations_done
Internal data to prevent doing update_initial_durations() twice.
Definition: avformat.h:1190
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:521
void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx)
enum AVCodecID audio_codec_id
Forced audio codec_id.
Definition: avformat.h:1506
int av_stream_add_side_data(AVStream *st, enum AVPacketSideDataType type, uint8_t *data, size_t size)
Wrap an existing array as stream side data.
Definition: utils.c:5114
enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name, const char *filename, const char *mime_type, enum AVMediaType type)
Guess the codec ID based upon muxer and filename.
Definition: format.c:133
int max_streams
The maximum number of streams.
Definition: avformat.h:1918
typedef void(APIENTRY *FF_PFNGLACTIVETEXTUREPROC)(GLenum texture)
int av_find_default_stream_index(AVFormatContext *s)
Definition: utils.c:1798
void av_format_set_opaque(AVFormatContext *s, void *opaque)
const char * name
Definition: avformat.h:524
Duration estimated from a stream with a known duration.
Definition: avformat.h:1318
AVFormatContext * ctx
Definition: movenc.c:48
uint8_t dts_ordered
Definition: avformat.h:1202
int avoid_negative_ts
Avoid negative timestamps during muxing.
Definition: avformat.h:1645
int(* control_message)(struct AVFormatContext *s, int type, void *data, size_t data_size)
Allows sending messages from application to device.
Definition: avformat.h:596
AVDictionary * metadata
Definition: avformat.h:958
uint8_t * av_stream_new_side_data(AVStream *stream, enum AVPacketSideDataType type, int size)
Allocate new information from stream.
Definition: utils.c:5150
AVOutputFormat * av_guess_format(const char *short_name, const char *filename, const char *mime_type)
Return the output format in the list of registered output formats which best matches the provided par...
Definition: format.c:98
int probe_score
format probing score.
Definition: avformat.h:1738
void av_register_input_format(AVInputFormat *format)
Definition: format.c:61
void av_format_set_audio_codec(AVFormatContext *s, AVCodec *c)
Libavformat version macros.
int64_t skip_initial_bytes
Skip initial bytes when opening stream.
Definition: avformat.h:1708
void(* get_output_timestamp)(struct AVFormatContext *s, int stream, int64_t *dts, int64_t *wall)
Definition: avformat.h:591
int(* read_pause)(struct AVFormatContext *)
Pause playing - only meaningful if using a network-based format (RTSP).
Definition: avformat.h:776
AVOutputFormat * av_oformat_next(const AVOutputFormat *f)
If f is NULL, returns the first registered output format, if f is non-NULL, returns the next register...
Definition: format.c:53
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:552
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:493
void * av_format_get_opaque(const AVFormatContext *s)
int64_t max_analyze_duration
Maximum duration (in AV_TIME_BASE units) of the data read from input in avformat_find_stream_info().
Definition: avformat.h:1488
int(* get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list)
Returns device list with it properties.
Definition: avformat.h:613
int av_get_frame_filename(char *buf, int buf_size, const char *path, int number)
Definition: utils.c:4456
uint8_t pts_reorder_error_count[MAX_REORDER_DELAY+1]
Definition: avformat.h:1196
int ts_id
Transport stream id.
Definition: avformat.h:1654
const char * long_name
Descriptive name for the format, meant to be more human-readable than name.
Definition: avformat.h:671
int metadata_header_padding
Number of bytes to be written as padding in a metadata header.
Definition: avformat.h:1814
int av_format_get_probe_score(const AVFormatContext *s)
Definition: utils.c:218
Stream structure.
Definition: avformat.h:889
int(* create_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps)
Initialize device capabilities submodule.
Definition: avformat.h:618
int64_t end
chapter start/end time in time_base units
Definition: avformat.h:1298
int avformat_queue_attached_pictures(AVFormatContext *s)
Definition: utils.c:452
void av_register_output_format(AVOutputFormat *format)
Definition: format.c:73
int avformat_network_deinit(void)
Undo the initialization done by avformat_network_init.
Definition: utils.c:4705
uint8_t dts_misordered
Definition: avformat.h:1203
int64_t pts_reorder_error[MAX_REORDER_DELAY+1]
Internal data to generate dts from pts.
Definition: avformat.h:1195
int64_t end_time
Definition: avformat.h:1285
Libavcodec external API header.
struct AVOutputFormat * next
Definition: avformat.h:561
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:756
int debug
Flags to enable debugging.
Definition: avformat.h:1597
AVIOContext * pb
I/O context.
Definition: avformat.h:1380
const struct AVCodecTag *const * codec_tag
List of supported codec_id-codec_tag pairs, ordered by "better choice first".
Definition: avformat.h:549
main external API structure.
Definition: avcodec.h:1682
int io_repositioned
IO repositioned flag.
Definition: avformat.h:1775
int av_filename_number_test(const char *filename)
Check whether filename actually is a numbered sequence generator.
Definition: utils.c:306
void av_format_set_video_codec(AVFormatContext *s, AVCodec *c)
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) returnNULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt)>2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);returnNULL;}returnac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_log(ac->avr, AV_LOG_TRACE,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> in
int(* read_packet)(struct AVFormatContext *, AVPacket *pkt)
Read one packet and put it in 'pkt'.
Definition: avformat.h:740
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:4401
int pts_wrap_behavior
behavior on wrap detection
Definition: avformat.h:1288
void * buf
Definition: avisynth_c.h:690
double(* duration_error)[2][MAX_STD_TIMEBASES]
Definition: avformat.h:1027
GLint GLenum type
Definition: opengl_enc.c:105
int nb_index_entries
Definition: avformat.h:1089
static const char * format
Definition: movenc.c:47
Describe the class of an AVClass context structure.
Definition: log.h:67
int index
Definition: gxfenc.c:89
int(* create_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps)
Initialize device capabilities submodule.
Definition: avformat.h:796
enum AVCodecID subtitle_codec
default subtitle codec
Definition: avformat.h:536
Rational number (pair of numerator and denominator).
Definition: rational.h:58
int64_t last_dts
Definition: avformat.h:1023
AVRational display_aspect_ratio
display aspect ratio (0 if unknown)
Definition: avformat.h:1222
AVRational av_stream_get_r_frame_rate(const AVStream *s)
const AVClass * av_class
A class for logging and AVOptions.
Definition: avformat.h:1343
AVMediaType
Definition: avutil.h:199
int(* interleave_packet)(struct AVFormatContext *, AVPacket *out, AVPacket *in, int flush)
Currently only used to set pixel format if not YUV420P.
Definition: avformat.h:580
int64_t fps_last_dts
Definition: avformat.h:1045
int found_decoder
0 -> decoder has not been searched for yet.
Definition: avformat.h:1036
void avformat_free_context(AVFormatContext *s)
Free an AVFormatContext and all its streams.
Definition: utils.c:4150
This structure contains the data a format has to probe a file.
Definition: avformat.h:461
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: utils.c:1688
List of devices.
Definition: avdevice.h:461
AVTimebaseSource
Apply a list of bitstream filters to a packet.
Definition: avformat.h:2969
int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Seek to timestamp ts.
Definition: utils.c:2447
int seek2any
Force seeking to any (also non key) frames.
Definition: avformat.h:1722
full parsing and repack of the first frame only, only implemented for H.264 currently ...
Definition: avformat.h:813
int raw_codec_id
Raw demuxers store their codec ID here.
Definition: avformat.h:710
AVDictionary * metadata
Definition: avformat.h:1271
int64_t codec_info_duration
Definition: avformat.h:1028
static int64_t pts
Global timestamp for the audio frames.
int fps_first_dts_idx
Definition: avformat.h:1044
av_format_control_message av_format_get_control_message_cb(const AVFormatContext *s)
int64_t start_time
Position of the first frame of the component, in AV_TIME_BASE fractional seconds. ...
Definition: avformat.h:1423
const char * mime_type
Comma-separated list of mime types.
Definition: avformat.h:696
uint8_t level
Definition: svq3.c:207
#define attribute_deprecated
Definition: attributes.h:94
Duration accurately estimated from PTSes.
Definition: avformat.h:1317
#define av_warn_unused_result
Definition: attributes.h:56
int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Seek to the keyframe at timestamp.
Definition: utils.c:2424
int64_t start
Definition: avformat.h:1298
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:943
int64_t interleaver_chunk_duration
Definition: avformat.h:1113
const char * extensions
If extensions are defined, then no probe is done.
Definition: avformat.h:685
const uint8_t * key
Definition: avformat.h:1490
full parsing and repack
Definition: avformat.h:810
int
int av_interleaved_write_uncoded_frame(AVFormatContext *s, int stream_index, AVFrame *frame)
Write an uncoded frame to an output media file.
Definition: mux.c:1427
struct AVPacketList * next
Definition: avformat.h:1956
int pts_wrap_behavior
Options for behavior, when a wrap is detected.
Definition: avformat.h:1185
int(* read_play)(struct AVFormatContext *)
Start/resume playing - only meaningful if using a network-based format (RTSP).
Definition: avformat.h:770
enum AVCodecID data_codec
default data codec
Definition: avformat.h:624
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
Definition: utils.c:3351
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:936
AVCodec * video_codec
Forced video codec.
Definition: avformat.h:1783
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:1678
int error_recognition
Error recognition; higher values will detect more errors but may misdetect some more or less valid pa...
Definition: avformat.h:1581
int disposition
AV_DISPOSITION_* bit field.
Definition: avformat.h:947
AVStreamParseType
Definition: avformat.h:808
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:1306
int pts_wrap_bits
number of bits in pts (used for wrapping control)
Definition: avformat.h:1050
AVRational time_base
time base in which the start/end timestamps are specified
Definition: avformat.h:1297
av_format_control_message control_message_cb
Callback used by devices to communicate with application.
Definition: avformat.h:1825
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:945
struct AVInputFormat * iformat
The input container format.
Definition: avformat.h:1350
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: utils.c:4186
int av_write_uncoded_frame(AVFormatContext *s, int stream_index, AVFrame *frame)
Write an uncoded frame to an output media file.
Definition: mux.c:1421
int64_t codec_info_duration_fields
Definition: avformat.h:1029
unsigned int index_entries_allocated_size
Definition: avformat.h:1090
int64_t mux_ts_offset
Timestamp offset added to timestamps before muxing NOT PART OF PUBLIC API.
Definition: avformat.h:1168
int skip_to_keyframe
Indicates that everything up to the next keyframe should be discarded.
Definition: avformat.h:1127
enum AVCodecID data_codec_id
Forced Data codec_id.
Definition: avformat.h:1847
AVCodec * subtitle_codec
Forced subtitle codec.
Definition: avformat.h:1799
int(* AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options)
Definition: avformat.h:1309
AVCodec * data_codec
Forced data codec.
Definition: avformat.h:1807
enum AVCodecID audio_codec
default audio codec
Definition: avformat.h:534
char * codec_whitelist
',' separated list of allowed decoders.
Definition: avformat.h:1753
int(* get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list)
Returns device list with it properties.
Definition: avformat.h:790
int max_chunk_duration
Max chunk time in microseconds.
Definition: avformat.h:1670
struct AVCodecParserContext * parser
Definition: avformat.h:1077
void * priv_data
Format private data.
Definition: avformat.h:1366
int pcr_pid
Definition: avformat.h:1275
int codec_info_nb_frames
Number of frames that have been demuxed during avformat_find_stream_info()
Definition: avformat.h:1073
static AVCodec * c
void av_format_set_control_message_cb(AVFormatContext *s, av_format_control_message callback)
int avformat_open_input(AVFormatContext **ps, const char *url, AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: utils.c:509
AVDiscard
Definition: avcodec.h:778
int av_format_get_metadata_header_padding(const AVFormatContext *s)
char * av_stream_get_recommended_encoder_configuration(const AVStream *s)
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
Definition: mux.c:1294
char * protocol_blacklist
',' separated list of disallowed protocols.
Definition: avformat.h:1911
int64_t duration
Duration of the stream, in AV_TIME_BASE fractional seconds.
Definition: avformat.h:1433
int avformat_flush(AVFormatContext *s)
Discard all internally buffered data.
Definition: utils.c:2504
void av_format_set_metadata_header_padding(AVFormatContext *s, int c)
FILE * out
Definition: movenc.c:54
int64_t last_IP_pts
Definition: avformat.h:1062
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:784
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:664
AVCodecParameters * codecpar
Definition: avformat.h:1241
int copy_tb
Definition: ffmpeg_opt.c:113
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:79
int fps_last_dts_idx
Definition: avformat.h:1046
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:926
struct AVInputFormat * next
Definition: avformat.h:705
AVCodec * av_format_get_data_codec(const AVFormatContext *s)
#define MKTAG(a, b, c, d)
Definition: common.h:342
unsigned int av_codec_get_tag(const struct AVCodecTag *const *tags, enum AVCodecID id)
Get the codec tag for the given codec id id.
const char * extensions
comma-separated filename extensions
Definition: avformat.h:532
enum AVDiscard discard
Selects which packets can be discarded at will and do not need to be demuxed.
Definition: avformat.h:949
AVRational r_frame_rate
Real base framerate of the stream.
Definition: avformat.h:1103
int(* io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags, AVDictionary **options)
Definition: avformat.h:1898
AVInputFormat * av_probe_input_format(AVProbeData *pd, int is_opened)
Guess the file format.
Definition: format.c:260
const char * mime_type
Definition: avformat.h:531
int request_probe
stream probing state -1 -> probing finished 0 -> no probing requested rest -> perform probing with re...
Definition: avformat.h:1122
Following API allows user to probe device capabilities (supported codecs, pixel formats, sample formats, resolutions, channel counts, etc).
Definition: avdevice.h:401
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:1686
This structure stores compressed data.
Definition: avcodec.h:1584
void av_register_all(void)
Initialize libavformat and register all the muxers, demuxers and protocols.
Definition: allformats.c:44
int(* write_trailer)(struct AVFormatContext *)
Definition: avformat.h:576
void(* io_close)(struct AVFormatContext *s, AVIOContext *pb)
A callback for closing the streams opened with AVFormatContext.io_open().
Definition: avformat.h:1904
#define MAX_STD_TIMEBASES
Stream information used internally by avformat_find_stream_info()
Definition: avformat.h:1021
const struct AVCodecTag *const * codec_tag
Definition: avformat.h:687
int64_t av_stream_get_end_pts(const AVStream *st)
Returns the pts of the last muxed packet + its duration.
Definition: utils.c:122
AVPacket attached_pic
For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet will contain the attached pictu...
Definition: avformat.h:976
struct AVPacketList * last_in_packet_buffer
last packet in packet_buffer for this stream when muxing.
Definition: avformat.h:1082
AVInputFormat * av_iformat_next(const AVInputFormat *f)
If f is NULL, returns the first registered input format, if f is non-NULL, returns the next registere...
Definition: format.c:45
int64_t last_discard_sample
The sample after last sample that is intended to be discarded after first_discard_sample.
Definition: avformat.h:1156
AVProgram ** programs
Definition: avformat.h:1494