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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 /*************************************************/
441 /* input/output formats */
442 
443 struct AVCodecTag;
444 
445 /**
446  * This structure contains the data a format has to probe a file.
447  */
448 typedef struct AVProbeData {
449  const char *filename;
450  unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
451  int buf_size; /**< Size of buf except extra allocated bytes */
452  const char *mime_type; /**< mime_type, when known. */
453 } AVProbeData;
454 
455 #define AVPROBE_SCORE_RETRY (AVPROBE_SCORE_MAX/4)
456 #define AVPROBE_SCORE_STREAM_RETRY (AVPROBE_SCORE_MAX/4-1)
457 
458 #define AVPROBE_SCORE_EXTENSION 50 ///< score for file extension
459 #define AVPROBE_SCORE_MIME 75 ///< score for file mime type
460 #define AVPROBE_SCORE_MAX 100 ///< maximum score
461 
462 #define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
463 
464 /// Demuxer will use avio_open, no opened file should be provided by the caller.
465 #define AVFMT_NOFILE 0x0001
466 #define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
467 #define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
468 #define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
469 #define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
470 #define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
471 #define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */
472 #define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */
473 #define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */
474 #define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */
475 #define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fall back on binary search via read_timestamp */
476 #define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fall back on generic search */
477 #define AVFMT_NO_BYTE_SEEK 0x8000 /**< Format does not allow seeking by bytes */
478 #define AVFMT_ALLOW_FLUSH 0x10000 /**< Format allows flushing. If not set, the muxer will not receive a NULL packet in the write_packet function. */
479 #define AVFMT_TS_NONSTRICT 0x20000 /**< Format does not require strictly
480  increasing timestamps, but they must
481  still be monotonic */
482 #define AVFMT_TS_NEGATIVE 0x40000 /**< Format allows muxing negative
483  timestamps. If not set the timestamp
484  will be shifted in av_write_frame and
485  av_interleaved_write_frame so they
486  start from 0.
487  The user or muxer can override this through
488  AVFormatContext.avoid_negative_ts
489  */
490 
491 #define AVFMT_SEEK_TO_PTS 0x4000000 /**< Seeking is based on PTS */
492 
493 /**
494  * @addtogroup lavf_encoding
495  * @{
496  */
497 typedef struct AVOutputFormat {
498  const char *name;
499  /**
500  * Descriptive name for the format, meant to be more human-readable
501  * than name. You should use the NULL_IF_CONFIG_SMALL() macro
502  * to define it.
503  */
504  const char *long_name;
505  const char *mime_type;
506  const char *extensions; /**< comma-separated filename extensions */
507  /* output support */
508  enum AVCodecID audio_codec; /**< default audio codec */
509  enum AVCodecID video_codec; /**< default video codec */
510  enum AVCodecID subtitle_codec; /**< default subtitle codec */
511  /**
512  * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER,
513  * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
514  * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH,
515  * AVFMT_TS_NONSTRICT, AVFMT_TS_NEGATIVE
516  */
517  int flags;
519  /**
520  * List of supported codec_id-codec_tag pairs, ordered by "better
521  * choice first". The arrays are all terminated by AV_CODEC_ID_NONE.
522  */
523  const struct AVCodecTag * const *codec_tag;
524 
525 
526  const AVClass *priv_class; ///< AVClass for the private context
527 
528  /*****************************************************************
529  * No fields below this line are part of the public API. They
530  * may not be used outside of libavformat and can be changed and
531  * removed at will.
532  * New public fields should be added right above.
533  *****************************************************************
534  */
536  /**
537  * size of private data so that it can be allocated in the wrapper
538  */
539  int priv_data_size;
540 
541  int (*write_header)(struct AVFormatContext *);
542  /**
543  * Write a packet. If AVFMT_ALLOW_FLUSH is set in flags,
544  * pkt can be NULL in order to flush data buffered in the muxer.
545  * When flushing, return 0 if there still is more data to flush,
546  * or 1 if everything was flushed and there is no more buffered
547  * data.
548  */
551  /**
552  * Currently only used to set pixel format if not YUV420P.
553  */
555  AVPacket *in, int flush);
556  /**
557  * Test if the given codec can be stored in this container.
558  *
559  * @return 1 if the codec is supported, 0 if it is not.
560  * A negative number if unknown.
561  * MKTAG('A', 'P', 'I', 'C') if the codec is only supported as AV_DISPOSITION_ATTACHED_PIC
562  */
563  int (*query_codec)(enum AVCodecID id, int std_compliance);
564 
565  void (*get_output_timestamp)(struct AVFormatContext *s, int stream,
566  int64_t *dts, int64_t *wall);
567  /**
568  * Allows sending messages from application to device.
569  */
570  int (*control_message)(struct AVFormatContext *s, int type,
571  void *data, size_t data_size);
573  /**
574  * Write an uncoded AVFrame.
575  *
576  * See av_write_uncoded_frame() for details.
577  *
578  * The library will free *frame afterwards, but the muxer can prevent it
579  * by setting the pointer to NULL.
580  */
581  int (*write_uncoded_frame)(struct AVFormatContext *, int stream_index,
582  AVFrame **frame, unsigned flags);
583  /**
584  * Returns device list with it properties.
585  * @see avdevice_list_devices() for more details.
586  */
587  int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
588  /**
589  * Initialize device capabilities submodule.
590  * @see avdevice_capabilities_create() for more details.
591  */
593  /**
594  * Free device capabilities submodule.
595  * @see avdevice_capabilities_free() for more details.
596  */
598  enum AVCodecID data_codec; /**< default data codec */
599  /**
600  * Initialize format. May allocate data here, and set any AVFormatContext or
601  * AVStream parameters that need to be set before packets are sent.
602  * This method must not write output.
603  *
604  * Return 0 if streams were fully configured, 1 if not, negative AVERROR on failure
605  *
606  * Any allocations made here must be freed in deinit().
607  */
608  int (*init)(struct AVFormatContext *);
609  /**
610  * Deinitialize format. If present, this is called whenever the muxer is being
611  * destroyed, regardless of whether or not the header has been written.
612  *
613  * If a trailer is being written, this is called after write_trailer().
614  *
615  * This is called if init() fails as well.
616  */
618  /**
619  * Set up any necessary bitstream filtering and extract any extra data needed
620  * for the global header.
621  * Return 0 if more packets from this stream must be checked; 1 if not.
622  */
623  int (*check_bitstream)(struct AVFormatContext *, const AVPacket *pkt);
625 /**
626  * @}
627  */
628 
629 /**
630  * @addtogroup lavf_decoding
631  * @{
632  */
633 typedef struct AVInputFormat {
634  /**
635  * A comma separated list of short names for the format. New names
636  * may be appended with a minor bump.
637  */
638  const char *name;
639 
640  /**
641  * Descriptive name for the format, meant to be more human-readable
642  * than name. You should use the NULL_IF_CONFIG_SMALL() macro
643  * to define it.
644  */
645  const char *long_name;
646 
647  /**
648  * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
649  * AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
650  * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK, AVFMT_SEEK_TO_PTS.
651  */
652  int flags;
653 
654  /**
655  * If extensions are defined, then no probe is done. You should
656  * usually not use extension format guessing because it is not
657  * reliable enough
658  */
659  const char *extensions;
660 
661  const struct AVCodecTag * const *codec_tag;
662 
663  const AVClass *priv_class; ///< AVClass for the private context
664 
665  /**
666  * Comma-separated list of mime types.
667  * It is used check for matching mime types while probing.
668  * @see av_probe_input_format2
669  */
670  const char *mime_type;
671 
672  /*****************************************************************
673  * No fields below this line are part of the public API. They
674  * may not be used outside of libavformat and can be changed and
675  * removed at will.
676  * New public fields should be added right above.
677  *****************************************************************
678  */
680 
681  /**
682  * Raw demuxers store their codec ID here.
683  */
684  int raw_codec_id;
685 
686  /**
687  * Size of private data so that it can be allocated in the wrapper.
688  */
689  int priv_data_size;
690 
691  /**
692  * Tell if a given file has a chance of being parsed as this format.
693  * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
694  * big so you do not have to check for that unless you need more.
695  */
696  int (*read_probe)(AVProbeData *);
697 
698  /**
699  * Read the format header and initialize the AVFormatContext
700  * structure. Return 0 if OK. 'avformat_new_stream' should be
701  * called to create new streams.
702  */
703  int (*read_header)(struct AVFormatContext *);
704 
705  /**
706  * Read one packet and put it in 'pkt'. pts and flags are also
707  * set. 'avformat_new_stream' can be called only if the flag
708  * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
709  * background thread).
710  * @return 0 on success, < 0 on error.
711  * When returning an error, pkt must not have been allocated
712  * or must be freed before returning
713  */
714  int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
715 
716  /**
717  * Close the stream. The AVFormatContext and AVStreams are not
718  * freed by this function
719  */
720  int (*read_close)(struct AVFormatContext *);
721 
722  /**
723  * Seek to a given timestamp relative to the frames in
724  * stream component stream_index.
725  * @param stream_index Must not be -1.
726  * @param flags Selects which direction should be preferred if no exact
727  * match is available.
728  * @return >= 0 on success (but not necessarily the new offset)
729  */
730  int (*read_seek)(struct AVFormatContext *,
731  int stream_index, int64_t timestamp, int flags);
732 
733  /**
734  * Get the next timestamp in stream[stream_index].time_base units.
735  * @return the timestamp or AV_NOPTS_VALUE if an error occurred
736  */
737  int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
738  int64_t *pos, int64_t pos_limit);
740  /**
741  * Start/resume playing - only meaningful if using a network-based format
742  * (RTSP).
743  */
744  int (*read_play)(struct AVFormatContext *);
745 
746  /**
747  * Pause playing - only meaningful if using a network-based format
748  * (RTSP).
749  */
750  int (*read_pause)(struct AVFormatContext *);
751 
752  /**
753  * Seek to timestamp ts.
754  * Seeking will be done so that the point from which all active streams
755  * can be presented successfully will be closest to ts and within min/max_ts.
756  * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
757  */
758  int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
760  /**
761  * Returns device list with it properties.
762  * @see avdevice_list_devices() for more details.
763  */
764  int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
765 
766  /**
767  * Initialize device capabilities submodule.
768  * @see avdevice_capabilities_create() for more details.
769  */
771 
772  /**
773  * Free device capabilities submodule.
774  * @see avdevice_capabilities_free() for more details.
775  */
777 } AVInputFormat;
778 /**
779  * @}
780  */
781 
782 enum AVStreamParseType {
784  AVSTREAM_PARSE_FULL, /**< full parsing and repack */
785  AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
786  AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
787  AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
788  AVSTREAM_PARSE_FULL_RAW, /**< full parsing and repack with timestamp and position generation by parser for raw
789  this assumes that each packet in the file contains no demuxer level headers and
790  just codec level data, otherwise position generation would fail */
791 };
793 typedef struct AVIndexEntry {
794  int64_t pos;
795  int64_t timestamp; /**<
796  * Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are available
797  * when seeking to this entry. That means preferable PTS on keyframe based formats.
798  * But demuxers can choose to store a different timestamp, if it is more convenient for the implementation or nothing better
799  * is known
800  */
801 #define AVINDEX_KEYFRAME 0x0001
802 #define AVINDEX_DISCARD_FRAME 0x0002 /**
803  * Flag is used to indicate which frame should be discarded after decoding.
804  */
805  int flags:2;
806  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).
807  int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
808 } AVIndexEntry;
809 
810 #define AV_DISPOSITION_DEFAULT 0x0001
811 #define AV_DISPOSITION_DUB 0x0002
812 #define AV_DISPOSITION_ORIGINAL 0x0004
813 #define AV_DISPOSITION_COMMENT 0x0008
814 #define AV_DISPOSITION_LYRICS 0x0010
815 #define AV_DISPOSITION_KARAOKE 0x0020
817 /**
818  * Track should be used during playback by default.
819  * Useful for subtitle track that should be displayed
820  * even when user did not explicitly ask for subtitles.
821  */
822 #define AV_DISPOSITION_FORCED 0x0040
823 #define AV_DISPOSITION_HEARING_IMPAIRED 0x0080 /**< stream for hearing impaired audiences */
824 #define AV_DISPOSITION_VISUAL_IMPAIRED 0x0100 /**< stream for visual impaired audiences */
825 #define AV_DISPOSITION_CLEAN_EFFECTS 0x0200 /**< stream without voice */
826 /**
827  * The stream is stored in the file as an attached picture/"cover art" (e.g.
828  * APIC frame in ID3v2). The first (usually only) packet associated with it
829  * will be returned among the first few packets read from the file unless
830  * seeking takes place. It can also be accessed at any time in
831  * AVStream.attached_pic.
832  */
833 #define AV_DISPOSITION_ATTACHED_PIC 0x0400
834 /**
835  * The stream is sparse, and contains thumbnail images, often corresponding
836  * to chapter markers. Only ever used with AV_DISPOSITION_ATTACHED_PIC.
837  */
838 #define AV_DISPOSITION_TIMED_THUMBNAILS 0x0800
839 
840 typedef struct AVStreamInternal AVStreamInternal;
841 
842 /**
843  * To specify text track kind (different from subtitles default).
844  */
845 #define AV_DISPOSITION_CAPTIONS 0x10000
846 #define AV_DISPOSITION_DESCRIPTIONS 0x20000
847 #define AV_DISPOSITION_METADATA 0x40000
848 #define AV_DISPOSITION_DEPENDENT 0x80000 ///< dependent audio stream (mix_type=0 in mpegts)
849 #define AV_DISPOSITION_STILL_IMAGE 0x100000 ///< still images in video stream (still_picture_flag=1 in mpegts)
850 
851 /**
852  * Options for behavior on timestamp wrap detection.
853  */
854 #define AV_PTS_WRAP_IGNORE 0 ///< ignore the wrap
855 #define AV_PTS_WRAP_ADD_OFFSET 1 ///< add the format specific offset on wrap detection
856 #define AV_PTS_WRAP_SUB_OFFSET -1 ///< subtract the format specific offset on wrap detection
858 /**
859  * Stream structure.
860  * New fields can be added to the end with minor version bumps.
861  * Removal, reordering and changes to existing fields require a major
862  * version bump.
863  * sizeof(AVStream) must not be used outside libav*.
864  */
865 typedef struct AVStream {
866  int index; /**< stream index in AVFormatContext */
867  /**
868  * Format-specific stream ID.
869  * decoding: set by libavformat
870  * encoding: set by the user, replaced by libavformat if left unset
871  */
872  int id;
873 #if FF_API_LAVF_AVCTX
874  /**
875  * @deprecated use the codecpar struct instead
876  */
878  AVCodecContext *codec;
879 #endif
880  void *priv_data;
882  /**
883  * This is the fundamental unit of time (in seconds) in terms
884  * of which frame timestamps are represented.
885  *
886  * decoding: set by libavformat
887  * encoding: May be set by the caller before avformat_write_header() to
888  * provide a hint to the muxer about the desired timebase. In
889  * avformat_write_header(), the muxer will overwrite this field
890  * with the timebase that will actually be used for the timestamps
891  * written into the file (which may or may not be related to the
892  * user-provided one, depending on the format).
893  */
895 
896  /**
897  * Decoding: pts of the first frame of the stream in presentation order, in stream time base.
898  * Only set this if you are absolutely 100% sure that the value you set
899  * it to really is the pts of the first frame.
900  * This may be undefined (AV_NOPTS_VALUE).
901  * @note The ASF header does NOT contain a correct start_time the ASF
902  * demuxer must NOT set this.
903  */
904  int64_t start_time;
905 
906  /**
907  * Decoding: duration of the stream, in stream time base.
908  * If a source file does not specify a duration, but does specify
909  * a bitrate, this value will be estimated from bitrate and file size.
910  *
911  * Encoding: May be set by the caller before avformat_write_header() to
912  * provide a hint to the muxer about the estimated duration.
913  */
914  int64_t duration;
915 
916  int64_t nb_frames; ///< number of frames in this stream if known or 0
917 
918  int disposition; /**< AV_DISPOSITION_* bit field */
919 
920  enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
921 
922  /**
923  * sample aspect ratio (0 if unknown)
924  * - encoding: Set by user.
925  * - decoding: Set by libavformat.
926  */
928 
930 
931  /**
932  * Average framerate
933  *
934  * - demuxing: May be set by libavformat when creating the stream or in
935  * avformat_find_stream_info().
936  * - muxing: May be set by the caller before avformat_write_header().
937  */
939 
940  /**
941  * For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet
942  * will contain the attached picture.
943  *
944  * decoding: set by libavformat, must not be modified by the caller.
945  * encoding: unused
946  */
948 
949  /**
950  * An array of side data that applies to the whole stream (i.e. the
951  * container does not allow it to change between packets).
952  *
953  * There may be no overlap between the side data in this array and side data
954  * in the packets. I.e. a given side data is either exported by the muxer
955  * (demuxing) / set by the caller (muxing) in this array, then it never
956  * appears in the packets, or the side data is exported / sent through
957  * the packets (always in the first packet where the value becomes known or
958  * changes), then it does not appear in this array.
959  *
960  * - demuxing: Set by libavformat when the stream is created.
961  * - muxing: May be set by the caller before avformat_write_header().
962  *
963  * Freed by libavformat in avformat_free_context().
964  *
965  * @see av_format_inject_global_side_data()
966  */
968  /**
969  * The number of elements in the AVStream.side_data array.
970  */
971  int nb_side_data;
972 
973  /**
974  * Flags for the user to detect events happening on the stream. Flags must
975  * be cleared by the user once the event has been handled.
976  * A combination of AVSTREAM_EVENT_FLAG_*.
977  */
978  int event_flags;
979 #define AVSTREAM_EVENT_FLAG_METADATA_UPDATED 0x0001 ///< The call resulted in updated metadata.
981  /**
982  * Real base framerate of the stream.
983  * This is the lowest framerate with which all timestamps can be
984  * represented accurately (it is the least common multiple of all
985  * framerates in the stream). Note, this value is just a guess!
986  * For example, if the time base is 1/90000 and all frames have either
987  * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
988  */
990 
991 #if FF_API_LAVF_FFSERVER
992  /**
993  * String containing pairs of key and values describing recommended encoder configuration.
994  * Pairs are separated by ','.
995  * Keys are separated from values by '='.
996  *
997  * @deprecated unused
998  */
1000  char *recommended_encoder_configuration;
1001 #endif
1002 
1003  /**
1004  * Codec parameters associated with this stream. Allocated and freed by
1005  * libavformat in avformat_new_stream() and avformat_free_context()
1006  * respectively.
1007  *
1008  * - demuxing: filled by libavformat on stream creation or in
1009  * avformat_find_stream_info()
1010  * - muxing: filled by the caller before avformat_write_header()
1011  */
1013 
1014  /*****************************************************************
1015  * All fields below this line are not part of the public API. They
1016  * may not be used outside of libavformat and can be changed and
1017  * removed at will.
1018  * Internal note: be aware that physically removing these fields
1019  * will break ABI. Replace removed fields with dummy fields, and
1020  * add new fields to AVStreamInternal.
1021  *****************************************************************
1022  */
1023 
1024 #define MAX_STD_TIMEBASES (30*12+30+3+6)
1025  /**
1026  * Stream information used internally by avformat_find_stream_info()
1027  */
1028  struct {
1029  int64_t last_dts;
1030  int64_t duration_gcd;
1031  int duration_count;
1032  int64_t rfps_duration_sum;
1034  int64_t codec_info_duration;
1037 
1038  /**
1039  * 0 -> decoder has not been searched for yet.
1040  * >0 -> decoder found
1041  * <0 -> decoder with codec_id == -found_decoder has not been found
1042  */
1045  int64_t last_duration;
1046 
1047  /**
1048  * Those are used for average framerate estimation.
1049  */
1050  int64_t fps_first_dts;
1051  int fps_first_dts_idx;
1052  int64_t fps_last_dts;
1053  int fps_last_dts_idx;
1055  } *info;
1056 
1057  int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
1058 
1059  // Timestamp generation support:
1060  /**
1061  * Timestamp corresponding to the last dts sync point.
1062  *
1063  * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
1064  * a DTS is received from the underlying container. Otherwise set to
1065  * AV_NOPTS_VALUE by default.
1066  */
1067  int64_t first_dts;
1068  int64_t cur_dts;
1069  int64_t last_IP_pts;
1070  int last_IP_duration;
1071 
1072  /**
1073  * Number of packets to buffer for codec probing
1074  */
1075  int probe_packets;
1077  /**
1078  * Number of frames that have been demuxed during avformat_find_stream_info()
1079  */
1081 
1082  /* av_read_frame() support */
1085 
1086  /**
1087  * last packet in packet_buffer for this stream when muxing.
1088  */
1091 #define MAX_REORDER_DELAY 16
1094  AVIndexEntry *index_entries; /**< Only used if the format does not
1095  support seeking natively. */
1096  int nb_index_entries;
1097  unsigned int index_entries_allocated_size;
1099  /**
1100  * Stream Identifier
1101  * This is the MPEG-TS stream identifier +1
1102  * 0 means unknown
1103  */
1104  int stream_identifier;
1106  /**
1107  * Details of the MPEG-TS program which created this stream.
1108  */
1109  int program_num;
1110  int pmt_version;
1111  int pmt_stream_idx;
1112 
1115 
1116  /**
1117  * stream probing state
1118  * -1 -> probing finished
1119  * 0 -> no probing requested
1120  * rest -> perform probing with request_probe being the minimum score to accept.
1121  * NOT PART OF PUBLIC API
1122  */
1124  /**
1125  * Indicates that everything up to the next keyframe
1126  * should be discarded.
1127  */
1128  int skip_to_keyframe;
1129 
1130  /**
1131  * Number of samples to skip at the start of the frame decoded from the next packet.
1132  */
1133  int skip_samples;
1134 
1135  /**
1136  * If not 0, the number of samples that should be skipped from the start of
1137  * the stream (the samples are removed from packets with pts==0, which also
1138  * assumes negative timestamps do not happen).
1139  * Intended for use with formats such as mp3 with ad-hoc gapless audio
1140  * support.
1141  */
1143 
1144  /**
1145  * If not 0, the first audio sample that should be discarded from the stream.
1146  * This is broken by design (needs global sample count), but can't be
1147  * avoided for broken by design formats such as mp3 with ad-hoc gapless
1148  * audio support.
1149  */
1150  int64_t first_discard_sample;
1152  /**
1153  * The sample after last sample that is intended to be discarded after
1154  * first_discard_sample. Works on frame boundaries only. Used to prevent
1155  * early EOF if the gapless info is broken (considered concatenated mp3s).
1156  */
1157  int64_t last_discard_sample;
1158 
1159  /**
1160  * Number of internally decoded frames, used internally in libavformat, do not access
1161  * its lifetime differs from info which is why it is not in that structure.
1162  */
1163  int nb_decoded_frames;
1164 
1165  /**
1166  * Timestamp offset added to timestamps before muxing
1167  * NOT PART OF PUBLIC API
1168  */
1169  int64_t mux_ts_offset;
1170 
1171  /**
1172  * Internal data to check for wrapping of the time stamp
1173  */
1174  int64_t pts_wrap_reference;
1175 
1176  /**
1177  * Options for behavior, when a wrap is detected.
1178  *
1179  * Defined by AV_PTS_WRAP_ values.
1180  *
1181  * If correction is enabled, there are two possibilities:
1182  * If the first time stamp is near the wrap point, the wrap offset
1183  * will be subtracted, which will create negative time stamps.
1184  * Otherwise the offset will be added.
1185  */
1186  int pts_wrap_behavior;
1187 
1188  /**
1189  * Internal data to prevent doing update_initial_durations() twice
1190  */
1192 
1193  /**
1194  * Internal data to generate dts from pts
1195  */
1198 
1199  /**
1200  * Internal data to analyze DTS and detect faulty mpeg streams
1201  */
1202  int64_t last_dts_for_order_check;
1206  /**
1207  * Internal data to inject global side data
1208  */
1210 
1211  /**
1212  * display aspect ratio (0 if unknown)
1213  * - encoding: unused
1214  * - decoding: Set by libavformat to calculate sample_aspect_ratio internally
1215  */
1217 
1218  /**
1219  * An opaque field for libavformat internal usage.
1220  * Must not be accessed in any way by callers.
1221  */
1222  AVStreamInternal *internal;
1223 } AVStream;
1224 
1225 #if FF_API_FORMAT_GET_SET
1226 /**
1227  * Accessors for some AVStream fields. These used to be provided for ABI
1228  * compatibility, and do not need to be used anymore.
1229  */
1231 AVRational av_stream_get_r_frame_rate(const AVStream *s);
1233 void av_stream_set_r_frame_rate(AVStream *s, AVRational r);
1234 #if FF_API_LAVF_FFSERVER
1236 char* av_stream_get_recommended_encoder_configuration(const AVStream *s);
1238 void av_stream_set_recommended_encoder_configuration(AVStream *s, char *configuration);
1239 #endif
1240 #endif
1241 
1243 
1244 /**
1245  * Returns the pts of the last muxed packet + its duration
1246  *
1247  * the retuned value is undefined when used with a demuxer.
1248  */
1249 int64_t av_stream_get_end_pts(const AVStream *st);
1250 
1251 #define AV_PROGRAM_RUNNING 1
1252 
1253 /**
1254  * New fields can be added to the end with minor version bumps.
1255  * Removal, reordering and changes to existing fields require a major
1256  * version bump.
1257  * sizeof(AVProgram) must not be used outside libav*.
1258  */
1259 typedef struct AVProgram {
1260  int id;
1261  int flags;
1262  enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
1263  unsigned int *stream_index;
1264  unsigned int nb_stream_indexes;
1266 
1267  int program_num;
1268  int pmt_pid;
1269  int pcr_pid;
1272  /*****************************************************************
1273  * All fields below this line are not part of the public API. They
1274  * may not be used outside of libavformat and can be changed and
1275  * removed at will.
1276  * New public fields should be added right above.
1277  *****************************************************************
1278  */
1279  int64_t start_time;
1280  int64_t end_time;
1281 
1282  int64_t pts_wrap_reference; ///< reference dts for wrap detection
1283  int pts_wrap_behavior; ///< behavior on wrap detection
1284 } AVProgram;
1285 
1286 #define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
1287  (streams are added dynamically) */
1288 #define AVFMTCTX_UNSEEKABLE 0x0002 /**< signal that the stream is definitely
1289  not seekable, and attempts to call the
1290  seek function will fail. For some
1291  network protocols (e.g. HLS), this can
1292  change dynamically at runtime. */
1293 
1294 typedef struct AVChapter {
1295  int id; ///< unique ID to identify the chapter
1296  AVRational time_base; ///< time base in which the start/end timestamps are specified
1297  int64_t start, end; ///< chapter start/end time in time_base units
1299 } AVChapter;
1300 
1301 
1302 /**
1303  * Callback used by devices to communicate with application.
1304  */
1305 typedef int (*av_format_control_message)(struct AVFormatContext *s, int type,
1306  void *data, size_t data_size);
1307 
1308 typedef int (*AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags,
1311 /**
1312  * The duration of a video can be estimated through various ways, and this enum can be used
1313  * to know how the duration was estimated.
1314  */
1316  AVFMT_DURATION_FROM_PTS, ///< Duration accurately estimated from PTSes
1317  AVFMT_DURATION_FROM_STREAM, ///< Duration estimated from a stream with a known duration
1318  AVFMT_DURATION_FROM_BITRATE ///< Duration estimated from bitrate (less accurate)
1319 };
1320 
1321 typedef struct AVFormatInternal AVFormatInternal;
1323 /**
1324  * Format I/O context.
1325  * New fields can be added to the end with minor version bumps.
1326  * Removal, reordering and changes to existing fields require a major
1327  * version bump.
1328  * sizeof(AVFormatContext) must not be used outside libav*, use
1329  * avformat_alloc_context() to create an AVFormatContext.
1330  *
1331  * Fields can be accessed through AVOptions (av_opt*),
1332  * the name string used matches the associated command line parameter name and
1333  * can be found in libavformat/options_table.h.
1334  * The AVOption/command line parameter names differ in some cases from the C
1335  * structure field names for historic reasons or brevity.
1336  */
1337 typedef struct AVFormatContext {
1338  /**
1339  * A class for logging and @ref avoptions. Set by avformat_alloc_context().
1340  * Exports (de)muxer private options if they exist.
1341  */
1342  const AVClass *av_class;
1343 
1344  /**
1345  * The input container format.
1346  *
1347  * Demuxing only, set by avformat_open_input().
1348  */
1349  struct AVInputFormat *iformat;
1350 
1351  /**
1352  * The output container format.
1353  *
1354  * Muxing only, must be set by the caller before avformat_write_header().
1355  */
1357 
1358  /**
1359  * Format private data. This is an AVOptions-enabled struct
1360  * if and only if iformat/oformat.priv_class is not NULL.
1361  *
1362  * - muxing: set by avformat_write_header()
1363  * - demuxing: set by avformat_open_input()
1364  */
1365  void *priv_data;
1366 
1367  /**
1368  * I/O context.
1369  *
1370  * - demuxing: either set by the user before avformat_open_input() (then
1371  * the user must close it manually) or set by avformat_open_input().
1372  * - muxing: set by the user before avformat_write_header(). The caller must
1373  * take care of closing / freeing the IO context.
1374  *
1375  * Do NOT set this field if AVFMT_NOFILE flag is set in
1376  * iformat/oformat.flags. In such a case, the (de)muxer will handle
1377  * I/O in some other way and this field will be NULL.
1378  */
1380 
1381  /* stream info */
1382  /**
1383  * Flags signalling stream properties. A combination of AVFMTCTX_*.
1384  * Set by libavformat.
1385  */
1386  int ctx_flags;
1387 
1388  /**
1389  * Number of elements in AVFormatContext.streams.
1390  *
1391  * Set by avformat_new_stream(), must not be modified by any other code.
1392  */
1393  unsigned int nb_streams;
1394  /**
1395  * A list of all streams in the file. New streams are created with
1396  * avformat_new_stream().
1397  *
1398  * - demuxing: streams are created by libavformat in avformat_open_input().
1399  * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
1400  * appear in av_read_frame().
1401  * - muxing: streams are created by the user before avformat_write_header().
1402  *
1403  * Freed by libavformat in avformat_free_context().
1404  */
1405  AVStream **streams;
1406 
1407 #if FF_API_FORMAT_FILENAME
1408  /**
1409  * input or output filename
1410  *
1411  * - demuxing: set by avformat_open_input()
1412  * - muxing: may be set by the caller before avformat_write_header()
1413  *
1414  * @deprecated Use url instead.
1415  */
1417  char filename[1024];
1418 #endif
1420  /**
1421  * input or output URL. Unlike the old filename field, this field has no
1422  * length restriction.
1423  *
1424  * - demuxing: set by avformat_open_input(), initialized to an empty
1425  * string if url parameter was NULL in avformat_open_input().
1426  * - muxing: may be set by the caller before calling avformat_write_header()
1427  * (or avformat_init_output() if that is called first) to a string
1428  * which is freeable by av_free(). Set to an empty string if it
1429  * was NULL in avformat_init_output().
1430  *
1431  * Freed by libavformat in avformat_free_context().
1432  */
1433  char *url;
1434 
1435  /**
1436  * Position of the first frame of the component, in
1437  * AV_TIME_BASE fractional seconds. NEVER set this value directly:
1438  * It is deduced from the AVStream values.
1439  *
1440  * Demuxing only, set by libavformat.
1441  */
1442  int64_t start_time;
1443 
1444  /**
1445  * Duration of the stream, in AV_TIME_BASE fractional
1446  * seconds. Only set this value if you know none of the individual stream
1447  * durations and also do not set any of them. This is deduced from the
1448  * AVStream values if not set.
1449  *
1450  * Demuxing only, set by libavformat.
1451  */
1452  int64_t duration;
1453 
1454  /**
1455  * Total stream bitrate in bit/s, 0 if not
1456  * available. Never set it directly if the file_size and the
1457  * duration are known as FFmpeg can compute it automatically.
1458  */
1459  int64_t bit_rate;
1460 
1461  unsigned int packet_size;
1462  int max_delay;
1463 
1464  /**
1465  * Flags modifying the (de)muxer behaviour. A combination of AVFMT_FLAG_*.
1466  * Set by the user before avformat_open_input() / avformat_write_header().
1467  */
1468  int flags;
1469 #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
1470 #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
1471 #define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
1472 #define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
1473 #define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
1474 #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
1475 #define AVFMT_FLAG_NOBUFFER 0x0040 ///< Do not buffer frames when possible
1476 #define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
1477 #define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted
1478 #define AVFMT_FLAG_FLUSH_PACKETS 0x0200 ///< Flush the AVIOContext every packet.
1479 /**
1480  * When muxing, try to avoid writing any random/volatile data to the output.
1481  * This includes any random IDs, real-time timestamps/dates, muxer version, etc.
1482  *
1483  * This flag is mainly intended for testing.
1484  */
1485 #define AVFMT_FLAG_BITEXACT 0x0400
1486 #define AVFMT_FLAG_MP4A_LATM 0x8000 ///< Enable RTP MP4A-LATM payload
1487 #define AVFMT_FLAG_SORT_DTS 0x10000 ///< try to interleave outputted packets by dts (using this flag can slow demuxing down)
1488 #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)
1489 #if FF_API_LAVF_KEEPSIDE_FLAG
1490 #define AVFMT_FLAG_KEEP_SIDE_DATA 0x40000 ///< Deprecated, does nothing.
1491 #endif
1492 #define AVFMT_FLAG_FAST_SEEK 0x80000 ///< Enable fast, but inaccurate seeks for some formats
1493 #define AVFMT_FLAG_SHORTEST 0x100000 ///< Stop muxing when the shortest stream stops.
1494 #define AVFMT_FLAG_AUTO_BSF 0x200000 ///< Add bitstream filters as requested by the muxer
1495 
1496  /**
1497  * Maximum size of the data read from input for determining
1498  * the input container format.
1499  * Demuxing only, set by the caller before avformat_open_input().
1500  */
1501  int64_t probesize;
1503  /**
1504  * Maximum duration (in AV_TIME_BASE units) of the data read
1505  * from input in avformat_find_stream_info().
1506  * Demuxing only, set by the caller before avformat_find_stream_info().
1507  * Can be set to 0 to let avformat choose using a heuristic.
1508  */
1509  int64_t max_analyze_duration;
1510 
1511  const uint8_t *key;
1512  int keylen;
1513 
1514  unsigned int nb_programs;
1516 
1517  /**
1518  * Forced video codec_id.
1519  * Demuxing: Set by user.
1520  */
1522 
1523  /**
1524  * Forced audio codec_id.
1525  * Demuxing: Set by user.
1526  */
1529  /**
1530  * Forced subtitle codec_id.
1531  * Demuxing: Set by user.
1532  */
1534 
1535  /**
1536  * Maximum amount of memory in bytes to use for the index of each stream.
1537  * If the index exceeds this size, entries will be discarded as
1538  * needed to maintain a smaller size. This can lead to slower or less
1539  * accurate seeking (depends on demuxer).
1540  * Demuxers for which a full in-memory index is mandatory will ignore
1541  * this.
1542  * - muxing: unused
1543  * - demuxing: set by user
1544  */
1545  unsigned int max_index_size;
1546 
1547  /**
1548  * Maximum amount of memory in bytes to use for buffering frames
1549  * obtained from realtime capture devices.
1550  */
1551  unsigned int max_picture_buffer;
1552 
1553  /**
1554  * Number of chapters in AVChapter array.
1555  * When muxing, chapters are normally written in the file header,
1556  * so nb_chapters should normally be initialized before write_header
1557  * is called. Some muxers (e.g. mov and mkv) can also write chapters
1558  * in the trailer. To write chapters in the trailer, nb_chapters
1559  * must be zero when write_header is called and non-zero when
1560  * write_trailer is called.
1561  * - muxing: set by user
1562  * - demuxing: set by libavformat
1563  */
1564  unsigned int nb_chapters;
1566 
1567  /**
1568  * Metadata that applies to the whole file.
1569  *
1570  * - demuxing: set by libavformat in avformat_open_input()
1571  * - muxing: may be set by the caller before avformat_write_header()
1572  *
1573  * Freed by libavformat in avformat_free_context().
1574  */
1576 
1577  /**
1578  * Start time of the stream in real world time, in microseconds
1579  * since the Unix epoch (00:00 1st January 1970). That is, pts=0 in the
1580  * stream was captured at this real world time.
1581  * - muxing: Set by the caller before avformat_write_header(). If set to
1582  * either 0 or AV_NOPTS_VALUE, then the current wall-time will
1583  * be used.
1584  * - demuxing: Set by libavformat. AV_NOPTS_VALUE if unknown. Note that
1585  * the value may become known after some number of frames
1586  * have been received.
1587  */
1588  int64_t start_time_realtime;
1590  /**
1591  * The number of frames used for determining the framerate in
1592  * avformat_find_stream_info().
1593  * Demuxing only, set by the caller before avformat_find_stream_info().
1594  */
1595  int fps_probe_size;
1596 
1597  /**
1598  * Error recognition; higher values will detect more errors but may
1599  * misdetect some more or less valid parts as errors.
1600  * Demuxing only, set by the caller before avformat_open_input().
1601  */
1603 
1604  /**
1605  * Custom interrupt callbacks for the I/O layer.
1606  *
1607  * demuxing: set by the user before avformat_open_input().
1608  * muxing: set by the user before avformat_write_header()
1609  * (mainly useful for AVFMT_NOFILE formats). The callback
1610  * should also be passed to avio_open2() if it's used to
1611  * open the file.
1612  */
1614 
1615  /**
1616  * Flags to enable debugging.
1617  */
1618  int debug;
1619 #define FF_FDEBUG_TS 0x0001
1620 
1621  /**
1622  * Maximum buffering duration for interleaving.
1623  *
1624  * To ensure all the streams are interleaved correctly,
1625  * av_interleaved_write_frame() will wait until it has at least one packet
1626  * for each stream before actually writing any packets to the output file.
1627  * When some streams are "sparse" (i.e. there are large gaps between
1628  * successive packets), this can result in excessive buffering.
1629  *
1630  * This field specifies the maximum difference between the timestamps of the
1631  * first and the last packet in the muxing queue, above which libavformat
1632  * will output a packet regardless of whether it has queued a packet for all
1633  * the streams.
1634  *
1635  * Muxing only, set by the caller before avformat_write_header().
1636  */
1637  int64_t max_interleave_delta;
1638 
1639  /**
1640  * Allow non-standard and experimental extension
1641  * @see AVCodecContext.strict_std_compliance
1642  */
1644 
1645  /**
1646  * Flags for the user to detect events happening on the file. Flags must
1647  * be cleared by the user once the event has been handled.
1648  * A combination of AVFMT_EVENT_FLAG_*.
1649  */
1650  int event_flags;
1651 #define AVFMT_EVENT_FLAG_METADATA_UPDATED 0x0001 ///< The call resulted in updated metadata.
1652 
1653  /**
1654  * Maximum number of packets to read while waiting for the first timestamp.
1655  * Decoding only.
1656  */
1658 
1659  /**
1660  * Avoid negative timestamps during muxing.
1661  * Any value of the AVFMT_AVOID_NEG_TS_* constants.
1662  * Note, this only works when using av_interleaved_write_frame. (interleave_packet_per_dts is in use)
1663  * - muxing: Set by user
1664  * - demuxing: unused
1665  */
1666  int avoid_negative_ts;
1667 #define AVFMT_AVOID_NEG_TS_AUTO -1 ///< Enabled when required by target format
1668 #define AVFMT_AVOID_NEG_TS_MAKE_NON_NEGATIVE 1 ///< Shift timestamps so they are non negative
1669 #define AVFMT_AVOID_NEG_TS_MAKE_ZERO 2 ///< Shift timestamps so that they start at 0
1670 
1671  /**
1672  * Transport stream id.
1673  * This will be moved into demuxer private options. Thus no API/ABI compatibility
1674  */
1675  int ts_id;
1676 
1677  /**
1678  * Audio preload in microseconds.
1679  * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1680  * - encoding: Set by user
1681  * - decoding: unused
1682  */
1684 
1685  /**
1686  * Max chunk time in microseconds.
1687  * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1688  * - encoding: Set by user
1689  * - decoding: unused
1690  */
1691  int max_chunk_duration;
1692 
1693  /**
1694  * Max chunk size in bytes
1695  * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1696  * - encoding: Set by user
1697  * - decoding: unused
1698  */
1699  int max_chunk_size;
1700 
1701  /**
1702  * forces the use of wallclock timestamps as pts/dts of packets
1703  * This has undefined results in the presence of B frames.
1704  * - encoding: unused
1705  * - decoding: Set by user
1706  */
1708 
1709  /**
1710  * avio flags, used to force AVIO_FLAG_DIRECT.
1711  * - encoding: unused
1712  * - decoding: Set by user
1713  */
1714  int avio_flags;
1715 
1716  /**
1717  * The duration field can be estimated through various ways, and this field can be used
1718  * to know how the duration was estimated.
1719  * - encoding: unused
1720  * - decoding: Read by user
1721  */
1723 
1724  /**
1725  * Skip initial bytes when opening stream
1726  * - encoding: unused
1727  * - decoding: Set by user
1728  */
1729  int64_t skip_initial_bytes;
1730 
1731  /**
1732  * Correct single timestamp overflows
1733  * - encoding: unused
1734  * - decoding: Set by user
1735  */
1736  unsigned int correct_ts_overflow;
1737 
1738  /**
1739  * Force seeking to any (also non key) frames.
1740  * - encoding: unused
1741  * - decoding: Set by user
1742  */
1744 
1745  /**
1746  * Flush the I/O context after each packet.
1747  * - encoding: Set by user
1748  * - decoding: unused
1749  */
1751 
1752  /**
1753  * format probing score.
1754  * The maximal score is AVPROBE_SCORE_MAX, its set when the demuxer probes
1755  * the format.
1756  * - encoding: unused
1757  * - decoding: set by avformat, read by user
1758  */
1759  int probe_score;
1760 
1761  /**
1762  * number of bytes to read maximally to identify format.
1763  * - encoding: unused
1764  * - decoding: set by user
1765  */
1766  int format_probesize;
1767 
1768  /**
1769  * ',' separated list of allowed decoders.
1770  * If NULL then all are allowed
1771  * - encoding: unused
1772  * - decoding: set by user
1773  */
1774  char *codec_whitelist;
1775 
1776  /**
1777  * ',' separated list of allowed demuxers.
1778  * If NULL then all are allowed
1779  * - encoding: unused
1780  * - decoding: set by user
1781  */
1782  char *format_whitelist;
1783 
1784  /**
1785  * An opaque field for libavformat internal usage.
1786  * Must not be accessed in any way by callers.
1787  */
1788  AVFormatInternal *internal;
1789 
1790  /**
1791  * IO repositioned flag.
1792  * This is set by avformat when the underlaying IO context read pointer
1793  * is repositioned, for example when doing byte based seeking.
1794  * Demuxers can use the flag to detect such changes.
1795  */
1797 
1798  /**
1799  * Forced video codec.
1800  * This allows forcing a specific decoder, even when there are multiple with
1801  * the same codec_id.
1802  * Demuxing: Set by user
1803  */
1805 
1806  /**
1807  * Forced audio codec.
1808  * This allows forcing a specific decoder, even when there are multiple with
1809  * the same codec_id.
1810  * Demuxing: Set by user
1811  */
1813 
1814  /**
1815  * Forced subtitle codec.
1816  * This allows forcing a specific decoder, even when there are multiple with
1817  * the same codec_id.
1818  * Demuxing: Set by user
1819  */
1821 
1822  /**
1823  * Forced data codec.
1824  * This allows forcing a specific decoder, even when there are multiple with
1825  * the same codec_id.
1826  * Demuxing: Set by user
1827  */
1829 
1830  /**
1831  * Number of bytes to be written as padding in a metadata header.
1832  * Demuxing: Unused.
1833  * Muxing: Set by user via av_format_set_metadata_header_padding.
1834  */
1836 
1837  /**
1838  * User data.
1839  * This is a place for some private data of the user.
1840  */
1841  void *opaque;
1843  /**
1844  * Callback used by devices to communicate with application.
1845  */
1847 
1848  /**
1849  * Output timestamp offset, in microseconds.
1850  * Muxing: set by user
1851  */
1852  int64_t output_ts_offset;
1853 
1854  /**
1855  * dump format separator.
1856  * can be ", " or "\n " or anything else
1857  * - muxing: Set by user.
1858  * - demuxing: Set by user.
1859  */
1861 
1862  /**
1863  * Forced Data codec_id.
1864  * Demuxing: Set by user.
1865  */
1867 
1868 #if FF_API_OLD_OPEN_CALLBACKS
1869  /**
1870  * Called to open further IO contexts when needed for demuxing.
1871  *
1872  * This can be set by the user application to perform security checks on
1873  * the URLs before opening them.
1874  * The function should behave like avio_open2(), AVFormatContext is provided
1875  * as contextual information and to reach AVFormatContext.opaque.
1876  *
1877  * If NULL then some simple checks are used together with avio_open2().
1878  *
1879  * Must not be accessed directly from outside avformat.
1880  * @See av_format_set_open_cb()
1881  *
1882  * Demuxing: Set by user.
1883  *
1884  * @deprecated Use io_open and io_close.
1885  */
1887  int (*open_cb)(struct AVFormatContext *s, AVIOContext **p, const char *url, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options);
1888 #endif
1889 
1890  /**
1891  * ',' separated list of allowed protocols.
1892  * - encoding: unused
1893  * - decoding: set by user
1894  */
1895  char *protocol_whitelist;
1896 
1897  /**
1898  * A callback for opening new IO streams.
1899  *
1900  * Whenever a muxer or a demuxer needs to open an IO stream (typically from
1901  * avformat_open_input() for demuxers, but for certain formats can happen at
1902  * other times as well), it will call this callback to obtain an IO context.
1903  *
1904  * @param s the format context
1905  * @param pb on success, the newly opened IO context should be returned here
1906  * @param url the url to open
1907  * @param flags a combination of AVIO_FLAG_*
1908  * @param options a dictionary of additional options, with the same
1909  * semantics as in avio_open2()
1910  * @return 0 on success, a negative AVERROR code on failure
1911  *
1912  * @note Certain muxers and demuxers do nesting, i.e. they open one or more
1913  * additional internal format contexts. Thus the AVFormatContext pointer
1914  * passed to this callback may be different from the one facing the caller.
1915  * It will, however, have the same 'opaque' field.
1916  */
1917  int (*io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url,
1918  int flags, AVDictionary **options);
1919 
1920  /**
1921  * A callback for closing the streams opened with AVFormatContext.io_open().
1922  */
1923  void (*io_close)(struct AVFormatContext *s, AVIOContext *pb);
1924 
1925  /**
1926  * ',' separated list of disallowed protocols.
1927  * - encoding: unused
1928  * - decoding: set by user
1929  */
1930  char *protocol_blacklist;
1932  /**
1933  * The maximum number of streams.
1934  * - encoding: unused
1935  * - decoding: set by user
1936  */
1938 
1939  /**
1940  * Skip duration calcuation in estimate_timings_from_pts.
1941  * - encoding: unused
1942  * - decoding: set by user
1943  */
1945 } AVFormatContext;
1946 
1947 #if FF_API_FORMAT_GET_SET
1948 /**
1949  * Accessors for some AVFormatContext fields. These used to be provided for ABI
1950  * compatibility, and do not need to be used anymore.
1951  */
1953 int av_format_get_probe_score(const AVFormatContext *s);
1955 AVCodec * av_format_get_video_codec(const AVFormatContext *s);
1957 void av_format_set_video_codec(AVFormatContext *s, AVCodec *c);
1959 AVCodec * av_format_get_audio_codec(const AVFormatContext *s);
1961 void av_format_set_audio_codec(AVFormatContext *s, AVCodec *c);
1963 AVCodec * av_format_get_subtitle_codec(const AVFormatContext *s);
1965 void av_format_set_subtitle_codec(AVFormatContext *s, AVCodec *c);
1967 AVCodec * av_format_get_data_codec(const AVFormatContext *s);
1969 void av_format_set_data_codec(AVFormatContext *s, AVCodec *c);
1971 int av_format_get_metadata_header_padding(const AVFormatContext *s);
1973 void av_format_set_metadata_header_padding(AVFormatContext *s, int c);
1975 void * av_format_get_opaque(const AVFormatContext *s);
1977 void av_format_set_opaque(AVFormatContext *s, void *opaque);
1979 av_format_control_message av_format_get_control_message_cb(const AVFormatContext *s);
1981 void av_format_set_control_message_cb(AVFormatContext *s, av_format_control_message callback);
1982 #if FF_API_OLD_OPEN_CALLBACKS
1983 attribute_deprecated AVOpenCallback av_format_get_open_cb(const AVFormatContext *s);
1984 attribute_deprecated void av_format_set_open_cb(AVFormatContext *s, AVOpenCallback callback);
1985 #endif
1986 #endif
1987 
1988 /**
1989  * This function will cause global side data to be injected in the next packet
1990  * of each stream as well as after any subsequent seek.
1991  */
1993 
1994 /**
1995  * Returns the method used to set ctx->duration.
1996  *
1997  * @return AVFMT_DURATION_FROM_PTS, AVFMT_DURATION_FROM_STREAM, or AVFMT_DURATION_FROM_BITRATE.
1998  */
2000 
2001 typedef struct AVPacketList {
2002  AVPacket pkt;
2003  struct AVPacketList *next;
2004 } AVPacketList;
2005 
2006 
2007 /**
2008  * @defgroup lavf_core Core functions
2009  * @ingroup libavf
2010  *
2011  * Functions for querying libavformat capabilities, allocating core structures,
2012  * etc.
2013  * @{
2014  */
2016 /**
2017  * Return the LIBAVFORMAT_VERSION_INT constant.
2018  */
2019 unsigned avformat_version(void);
2020 
2021 /**
2022  * Return the libavformat build-time configuration.
2023  */
2024 const char *avformat_configuration(void);
2025 
2026 /**
2027  * Return the libavformat license.
2028  */
2029 const char *avformat_license(void);
2030 
2031 #if FF_API_NEXT
2032 /**
2033  * Initialize libavformat and register all the muxers, demuxers and
2034  * protocols. If you do not call this function, then you can select
2035  * exactly which formats you want to support.
2036  *
2037  * @see av_register_input_format()
2038  * @see av_register_output_format()
2039  */
2041 void av_register_all(void);
2042 
2044 void av_register_input_format(AVInputFormat *format);
2046 void av_register_output_format(AVOutputFormat *format);
2047 #endif
2048 
2049 /**
2050  * Do global initialization of network libraries. This is optional,
2051  * and not recommended anymore.
2052  *
2053  * This functions only exists to work around thread-safety issues
2054  * with older GnuTLS or OpenSSL libraries. If libavformat is linked
2055  * to newer versions of those libraries, or if you do not use them,
2056  * calling this function is unnecessary. Otherwise, you need to call
2057  * this function before any other threads using them are started.
2058  *
2059  * This function will be deprecated once support for older GnuTLS and
2060  * OpenSSL libraries is removed, and this function has no purpose
2061  * anymore.
2062  */
2063 int avformat_network_init(void);
2064 
2065 /**
2066  * Undo the initialization done by avformat_network_init. Call it only
2067  * once for each time you called avformat_network_init.
2068  */
2069 int avformat_network_deinit(void);
2070 
2071 #if FF_API_NEXT
2072 /**
2073  * If f is NULL, returns the first registered input format,
2074  * if f is non-NULL, returns the next registered input format after f
2075  * or NULL if f is the last one.
2076  */
2078 AVInputFormat *av_iformat_next(const AVInputFormat *f);
2079 
2080 /**
2081  * If f is NULL, returns the first registered output format,
2082  * if f is non-NULL, returns the next registered output format after f
2083  * or NULL if f is the last one.
2084  */
2086 AVOutputFormat *av_oformat_next(const AVOutputFormat *f);
2087 #endif
2088 
2089 /**
2090  * Iterate over all registered muxers.
2091  *
2092  * @param opaque a pointer where libavformat will store the iteration state. Must
2093  * point to NULL to start the iteration.
2094  *
2095  * @return the next registered muxer or NULL when the iteration is
2096  * finished
2097  */
2098 const AVOutputFormat *av_muxer_iterate(void **opaque);
2099 
2100 /**
2101  * Iterate over all registered demuxers.
2102  *
2103  * @param opaque a pointer where libavformat will store the iteration state. Must
2104  * point to NULL to start the iteration.
2105  *
2106  * @return the next registered demuxer or NULL when the iteration is
2107  * finished
2108  */
2109 const AVInputFormat *av_demuxer_iterate(void **opaque);
2110 
2111 /**
2112  * Allocate an AVFormatContext.
2113  * avformat_free_context() can be used to free the context and everything
2114  * allocated by the framework within it.
2115  */
2117 
2118 /**
2119  * Free an AVFormatContext and all its streams.
2120  * @param s context to free
2121  */
2123 
2124 /**
2125  * Get the AVClass for AVFormatContext. It can be used in combination with
2126  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2127  *
2128  * @see av_opt_find().
2129  */
2130 const AVClass *avformat_get_class(void);
2131 
2132 /**
2133  * Add a new stream to a media file.
2134  *
2135  * When demuxing, it is called by the demuxer in read_header(). If the
2136  * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
2137  * be called in read_packet().
2138  *
2139  * When muxing, should be called by the user before avformat_write_header().
2140  *
2141  * User is required to call avcodec_close() and avformat_free_context() to
2142  * clean up the allocation by avformat_new_stream().
2143  *
2144  * @param s media file handle
2145  * @param c If non-NULL, the AVCodecContext corresponding to the new stream
2146  * will be initialized to use this codec. This is needed for e.g. codec-specific
2147  * defaults to be set, so codec should be provided if it is known.
2148  *
2149  * @return newly created stream or NULL on error.
2150  */
2152 
2153 /**
2154  * Wrap an existing array as stream side data.
2155  *
2156  * @param st stream
2157  * @param type side information type
2158  * @param data the side data array. It must be allocated with the av_malloc()
2159  * family of functions. The ownership of the data is transferred to
2160  * st.
2161  * @param size side information size
2162  * @return zero on success, a negative AVERROR code on failure. On failure,
2163  * the stream is unchanged and the data remains owned by the caller.
2164  */
2166  uint8_t *data, size_t size);
2167 
2168 /**
2169  * Allocate new information from stream.
2170  *
2171  * @param stream stream
2172  * @param type desired side information type
2173  * @param size side information size
2174  * @return pointer to fresh allocated data or NULL otherwise
2175  */
2177  enum AVPacketSideDataType type, int size);
2178 /**
2179  * Get side information from stream.
2180  *
2181  * @param stream stream
2182  * @param type desired side information type
2183  * @param size pointer for side information size to store (optional)
2184  * @return pointer to data if present or NULL otherwise
2185  */
2187  enum AVPacketSideDataType type, int *size);
2188 
2190 
2191 /**
2192  * @}
2193  */
2194 
2195 
2196 /**
2197  * Allocate an AVFormatContext for an output format.
2198  * avformat_free_context() can be used to free the context and
2199  * everything allocated by the framework within it.
2200  *
2201  * @param *ctx is set to the created format context, or to NULL in
2202  * case of failure
2203  * @param oformat format to use for allocating the context, if NULL
2204  * format_name and filename are used instead
2205  * @param format_name the name of output format to use for allocating the
2206  * context, if NULL filename is used instead
2207  * @param filename the name of the filename to use for allocating the
2208  * context, may be NULL
2209  * @return >= 0 in case of success, a negative AVERROR code in case of
2210  * failure
2211  */
2213  const char *format_name, const char *filename);
2214 
2215 /**
2216  * @addtogroup lavf_decoding
2217  * @{
2218  */
2219 
2220 /**
2221  * Find AVInputFormat based on the short name of the input format.
2222  */
2223 AVInputFormat *av_find_input_format(const char *short_name);
2224 
2225 /**
2226  * Guess the file format.
2227  *
2228  * @param pd data to be probed
2229  * @param is_opened Whether the file is already opened; determines whether
2230  * demuxers with or without AVFMT_NOFILE are probed.
2231  */
2232 AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
2233 
2234 /**
2235  * Guess the file format.
2236  *
2237  * @param pd data to be probed
2238  * @param is_opened Whether the file is already opened; determines whether
2239  * demuxers with or without AVFMT_NOFILE are probed.
2240  * @param score_max A probe score larger that this is required to accept a
2241  * detection, the variable is set to the actual detection
2242  * score afterwards.
2243  * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
2244  * to retry with a larger probe buffer.
2245  */
2246 AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max);
2247 
2248 /**
2249  * Guess the file format.
2250  *
2251  * @param is_opened Whether the file is already opened; determines whether
2252  * demuxers with or without AVFMT_NOFILE are probed.
2253  * @param score_ret The score of the best detection.
2254  */
2255 AVInputFormat *av_probe_input_format3(AVProbeData *pd, int is_opened, int *score_ret);
2256 
2257 /**
2258  * Probe a bytestream to determine the input format. Each time a probe returns
2259  * with a score that is too low, the probe buffer size is increased and another
2260  * attempt is made. When the maximum probe size is reached, the input format
2261  * with the highest score is returned.
2262  *
2263  * @param pb the bytestream to probe
2264  * @param fmt the input format is put here
2265  * @param url the url of the stream
2266  * @param logctx the log context
2267  * @param offset the offset within the bytestream to probe from
2268  * @param max_probe_size the maximum probe buffer size (zero for default)
2269  * @return the score in case of success, a negative value corresponding to an
2270  * the maximal score is AVPROBE_SCORE_MAX
2271  * AVERROR code otherwise
2272  */
2274  const char *url, void *logctx,
2275  unsigned int offset, unsigned int max_probe_size);
2276 
2277 /**
2278  * Like av_probe_input_buffer2() but returns 0 on success
2279  */
2281  const char *url, void *logctx,
2282  unsigned int offset, unsigned int max_probe_size);
2283 
2284 /**
2285  * Open an input stream and read the header. The codecs are not opened.
2286  * The stream must be closed with avformat_close_input().
2287  *
2288  * @param ps Pointer to user-supplied AVFormatContext (allocated by avformat_alloc_context).
2289  * May be a pointer to NULL, in which case an AVFormatContext is allocated by this
2290  * function and written into ps.
2291  * Note that a user-supplied AVFormatContext will be freed on failure.
2292  * @param url URL of the stream to open.
2293  * @param fmt If non-NULL, this parameter forces a specific input format.
2294  * Otherwise the format is autodetected.
2295  * @param options A dictionary filled with AVFormatContext and demuxer-private options.
2296  * On return this parameter will be destroyed and replaced with a dict containing
2297  * options that were not found. May be NULL.
2298  *
2299  * @return 0 on success, a negative AVERROR on failure.
2300  *
2301  * @note If you want to use custom IO, preallocate the format context and set its pb field.
2302  */
2304 
2307 
2308 /**
2309  * Read packets of a media file to get stream information. This
2310  * is useful for file formats with no headers such as MPEG. This
2311  * function also computes the real framerate in case of MPEG-2 repeat
2312  * frame mode.
2313  * The logical file position is not changed by this function;
2314  * examined packets may be buffered for later processing.
2315  *
2316  * @param ic media file handle
2317  * @param options If non-NULL, an ic.nb_streams long array of pointers to
2318  * dictionaries, where i-th member contains options for
2319  * codec corresponding to i-th stream.
2320  * On return each dictionary will be filled with options that were not found.
2321  * @return >=0 if OK, AVERROR_xxx on error
2322  *
2323  * @note this function isn't guaranteed to open all the codecs, so
2324  * options being non-empty at return is a perfectly normal behavior.
2325  *
2326  * @todo Let the user decide somehow what information is needed so that
2327  * we do not waste time getting stuff the user does not need.
2328  */
2330 
2331 /**
2332  * Find the programs which belong to a given stream.
2333  *
2334  * @param ic media file handle
2335  * @param last the last found program, the search will start after this
2336  * program, or from the beginning if it is NULL
2337  * @param s stream index
2338  * @return the next program which belongs to s, NULL if no program is found or
2339  * the last program is not among the programs of ic.
2340  */
2342 
2343 void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx);
2344 
2345 /**
2346  * Find the "best" stream in the file.
2347  * The best stream is determined according to various heuristics as the most
2348  * likely to be what the user expects.
2349  * If the decoder parameter is non-NULL, av_find_best_stream will find the
2350  * default decoder for the stream's codec; streams for which no decoder can
2351  * be found are ignored.
2352  *
2353  * @param ic media file handle
2354  * @param type stream type: video, audio, subtitles, etc.
2355  * @param wanted_stream_nb user-requested stream number,
2356  * or -1 for automatic selection
2357  * @param related_stream try to find a stream related (eg. in the same
2358  * program) to this one, or -1 if none
2359  * @param decoder_ret if non-NULL, returns the decoder for the
2360  * selected stream
2361  * @param flags flags; none are currently defined
2362  * @return the non-negative stream number in case of success,
2363  * AVERROR_STREAM_NOT_FOUND if no stream with the requested type
2364  * could be found,
2365  * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
2366  * @note If av_find_best_stream returns successfully and decoder_ret is not
2367  * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
2368  */
2370  enum AVMediaType type,
2371  int wanted_stream_nb,
2372  int related_stream,
2373  AVCodec **decoder_ret,
2374  int flags);
2375 
2376 /**
2377  * Return the next frame of a stream.
2378  * This function returns what is stored in the file, and does not validate
2379  * that what is there are valid frames for the decoder. It will split what is
2380  * stored in the file into frames and return one for each call. It will not
2381  * omit invalid data between valid frames so as to give the decoder the maximum
2382  * information possible for decoding.
2383  *
2384  * If pkt->buf is NULL, then the packet is valid until the next
2385  * av_read_frame() or until avformat_close_input(). Otherwise the packet
2386  * is valid indefinitely. In both cases the packet must be freed with
2387  * av_packet_unref when it is no longer needed. For video, the packet contains
2388  * exactly one frame. For audio, it contains an integer number of frames if each
2389  * frame has a known fixed size (e.g. PCM or ADPCM data). If the audio frames
2390  * have a variable size (e.g. MPEG audio), then it contains one frame.
2391  *
2392  * pkt->pts, pkt->dts and pkt->duration are always set to correct
2393  * values in AVStream.time_base units (and guessed if the format cannot
2394  * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
2395  * has B-frames, so it is better to rely on pkt->dts if you do not
2396  * decompress the payload.
2397  *
2398  * @return 0 if OK, < 0 on error or end of file
2399  */
2401 
2402 /**
2403  * Seek to the keyframe at timestamp.
2404  * 'timestamp' in 'stream_index'.
2405  *
2406  * @param s media file handle
2407  * @param stream_index If stream_index is (-1), a default
2408  * stream is selected, and timestamp is automatically converted
2409  * from AV_TIME_BASE units to the stream specific time_base.
2410  * @param timestamp Timestamp in AVStream.time_base units
2411  * or, if no stream is specified, in AV_TIME_BASE units.
2412  * @param flags flags which select direction and seeking mode
2413  * @return >= 0 on success
2414  */
2415 int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
2416  int flags);
2417 
2418 /**
2419  * Seek to timestamp ts.
2420  * Seeking will be done so that the point from which all active streams
2421  * can be presented successfully will be closest to ts and within min/max_ts.
2422  * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
2423  *
2424  * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
2425  * are the file position (this may not be supported by all demuxers).
2426  * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
2427  * in the stream with stream_index (this may not be supported by all demuxers).
2428  * Otherwise all timestamps are in units of the stream selected by stream_index
2429  * or if stream_index is -1, in AV_TIME_BASE units.
2430  * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
2431  * keyframes (this may not be supported by all demuxers).
2432  * If flags contain AVSEEK_FLAG_BACKWARD, it is ignored.
2433  *
2434  * @param s media file handle
2435  * @param stream_index index of the stream which is used as time base reference
2436  * @param min_ts smallest acceptable timestamp
2437  * @param ts target timestamp
2438  * @param max_ts largest acceptable timestamp
2439  * @param flags flags
2440  * @return >=0 on success, error code otherwise
2441  *
2442  * @note This is part of the new seek API which is still under construction.
2443  * Thus do not use this yet. It may change at any time, do not expect
2444  * ABI compatibility yet!
2445  */
2446 int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
2447 
2448 /**
2449  * Discard all internally buffered data. This can be useful when dealing with
2450  * discontinuities in the byte stream. Generally works only with formats that
2451  * can resync. This includes headerless formats like MPEG-TS/TS but should also
2452  * work with NUT, Ogg and in a limited way AVI for example.
2453  *
2454  * The set of streams, the detected duration, stream parameters and codecs do
2455  * not change when calling this function. If you want a complete reset, it's
2456  * better to open a new AVFormatContext.
2457  *
2458  * This does not flush the AVIOContext (s->pb). If necessary, call
2459  * avio_flush(s->pb) before calling this function.
2460  *
2461  * @param s media file handle
2462  * @return >=0 on success, error code otherwise
2463  */
2465 
2466 /**
2467  * Start playing a network-based stream (e.g. RTSP stream) at the
2468  * current position.
2469  */
2471 
2472 /**
2473  * Pause a network-based stream (e.g. RTSP stream).
2474  *
2475  * Use av_read_play() to resume it.
2476  */
2478 
2479 /**
2480  * Close an opened input AVFormatContext. Free it and all its contents
2481  * and set *s to NULL.
2482  */
2484 /**
2485  * @}
2486  */
2487 
2488 #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
2489 #define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
2490 #define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
2491 #define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
2492 
2493 /**
2494  * @addtogroup lavf_encoding
2495  * @{
2496  */
2497 
2498 #define AVSTREAM_INIT_IN_WRITE_HEADER 0 ///< stream parameters initialized in avformat_write_header
2499 #define AVSTREAM_INIT_IN_INIT_OUTPUT 1 ///< stream parameters initialized in avformat_init_output
2500 
2501 /**
2502  * Allocate the stream private data and write the stream header to
2503  * an output media file.
2504  *
2505  * @param s Media file handle, must be allocated with avformat_alloc_context().
2506  * Its oformat field must be set to the desired output format;
2507  * Its pb field must be set to an already opened AVIOContext.
2508  * @param options An AVDictionary filled with AVFormatContext and muxer-private options.
2509  * On return this parameter will be destroyed and replaced with a dict containing
2510  * options that were not found. May be NULL.
2511  *
2512  * @return AVSTREAM_INIT_IN_WRITE_HEADER on success if the codec had not already been fully initialized in avformat_init,
2513  * AVSTREAM_INIT_IN_INIT_OUTPUT on success if the codec had already been fully initialized in avformat_init,
2514  * negative AVERROR on failure.
2515  *
2516  * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_init_output.
2517  */
2520 
2521 /**
2522  * Allocate the stream private data and initialize the codec, but do not write the header.
2523  * May optionally be used before avformat_write_header to initialize stream parameters
2524  * before actually writing the header.
2525  * If using this function, do not pass the same options to avformat_write_header.
2526  *
2527  * @param s Media file handle, must be allocated with avformat_alloc_context().
2528  * Its oformat field must be set to the desired output format;
2529  * Its pb field must be set to an already opened AVIOContext.
2530  * @param options An AVDictionary filled with AVFormatContext and muxer-private options.
2531  * On return this parameter will be destroyed and replaced with a dict containing
2532  * options that were not found. May be NULL.
2533  *
2534  * @return AVSTREAM_INIT_IN_WRITE_HEADER on success if the codec requires avformat_write_header to fully initialize,
2535  * AVSTREAM_INIT_IN_INIT_OUTPUT on success if the codec has been fully initialized,
2536  * negative AVERROR on failure.
2537  *
2538  * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_write_header.
2539  */
2542 
2543 /**
2544  * Write a packet to an output media file.
2545  *
2546  * This function passes the packet directly to the muxer, without any buffering
2547  * or reordering. The caller is responsible for correctly interleaving the
2548  * packets if the format requires it. Callers that want libavformat to handle
2549  * the interleaving should call av_interleaved_write_frame() instead of this
2550  * function.
2551  *
2552  * @param s media file handle
2553  * @param pkt The packet containing the data to be written. Note that unlike
2554  * av_interleaved_write_frame(), this function does not take
2555  * ownership of the packet passed to it (though some muxers may make
2556  * an internal reference to the input packet).
2557  * <br>
2558  * This parameter can be NULL (at any time, not just at the end), in
2559  * order to immediately flush data buffered within the muxer, for
2560  * muxers that buffer up data internally before writing it to the
2561  * output.
2562  * <br>
2563  * Packet's @ref AVPacket.stream_index "stream_index" field must be
2564  * set to the index of the corresponding stream in @ref
2565  * AVFormatContext.streams "s->streams".
2566  * <br>
2567  * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2568  * must be set to correct values in the stream's timebase (unless the
2569  * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2570  * they can be set to AV_NOPTS_VALUE).
2571  * The dts for subsequent packets passed to this function must be strictly
2572  * increasing when compared in their respective timebases (unless the
2573  * output format is flagged with the AVFMT_TS_NONSTRICT, then they
2574  * merely have to be nondecreasing). @ref AVPacket.duration
2575  * "duration") should also be set if known.
2576  * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush
2577  *
2578  * @see av_interleaved_write_frame()
2579  */
2581 
2582 /**
2583  * Write a packet to an output media file ensuring correct interleaving.
2584  *
2585  * This function will buffer the packets internally as needed to make sure the
2586  * packets in the output file are properly interleaved in the order of
2587  * increasing dts. Callers doing their own interleaving should call
2588  * av_write_frame() instead of this function.
2589  *
2590  * Using this function instead of av_write_frame() can give muxers advance
2591  * knowledge of future packets, improving e.g. the behaviour of the mp4
2592  * muxer for VFR content in fragmenting mode.
2593  *
2594  * @param s media file handle
2595  * @param pkt The packet containing the data to be written.
2596  * <br>
2597  * If the packet is reference-counted, this function will take
2598  * ownership of this reference and unreference it later when it sees
2599  * fit.
2600  * The caller must not access the data through this reference after
2601  * this function returns. If the packet is not reference-counted,
2602  * libavformat will make a copy.
2603  * <br>
2604  * This parameter can be NULL (at any time, not just at the end), to
2605  * flush the interleaving queues.
2606  * <br>
2607  * Packet's @ref AVPacket.stream_index "stream_index" field must be
2608  * set to the index of the corresponding stream in @ref
2609  * AVFormatContext.streams "s->streams".
2610  * <br>
2611  * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2612  * must be set to correct values in the stream's timebase (unless the
2613  * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2614  * they can be set to AV_NOPTS_VALUE).
2615  * The dts for subsequent packets in one stream must be strictly
2616  * increasing (unless the output format is flagged with the
2617  * AVFMT_TS_NONSTRICT, then they merely have to be nondecreasing).
2618  * @ref AVPacket.duration "duration") should also be set if known.
2619  *
2620  * @return 0 on success, a negative AVERROR on error. Libavformat will always
2621  * take care of freeing the packet, even if this function fails.
2622  *
2623  * @see av_write_frame(), AVFormatContext.max_interleave_delta
2624  */
2626 
2627 /**
2628  * Write an uncoded frame to an output media file.
2629  *
2630  * The frame must be correctly interleaved according to the container
2631  * specification; if not, then av_interleaved_write_frame() must be used.
2632  *
2633  * See av_interleaved_write_frame() for details.
2634  */
2635 int av_write_uncoded_frame(AVFormatContext *s, int stream_index,
2636  AVFrame *frame);
2637 
2638 /**
2639  * Write an uncoded frame to an output media file.
2640  *
2641  * If the muxer supports it, this function makes it possible to write an AVFrame
2642  * structure directly, without encoding it into a packet.
2643  * It is mostly useful for devices and similar special muxers that use raw
2644  * video or PCM data and will not serialize it into a byte stream.
2645  *
2646  * To test whether it is possible to use it with a given muxer and stream,
2647  * use av_write_uncoded_frame_query().
2648  *
2649  * The caller gives up ownership of the frame and must not access it
2650  * afterwards.
2651  *
2652  * @return >=0 for success, a negative code on error
2653  */
2654 int av_interleaved_write_uncoded_frame(AVFormatContext *s, int stream_index,
2655  AVFrame *frame);
2656 
2657 /**
2658  * Test whether a muxer supports uncoded frame.
2659  *
2660  * @return >=0 if an uncoded frame can be written to that muxer and stream,
2661  * <0 if not
2662  */
2663 int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index);
2664 
2665 /**
2666  * Write the stream trailer to an output media file and free the
2667  * file private data.
2668  *
2669  * May only be called after a successful call to avformat_write_header.
2670  *
2671  * @param s media file handle
2672  * @return 0 if OK, AVERROR_xxx on error
2673  */
2675 
2676 /**
2677  * Return the output format in the list of registered output formats
2678  * which best matches the provided parameters, or return NULL if
2679  * there is no match.
2680  *
2681  * @param short_name if non-NULL checks if short_name matches with the
2682  * names of the registered formats
2683  * @param filename if non-NULL checks if filename terminates with the
2684  * extensions of the registered formats
2685  * @param mime_type if non-NULL checks if mime_type matches with the
2686  * MIME type of the registered formats
2687  */
2688 AVOutputFormat *av_guess_format(const char *short_name,
2689  const char *filename,
2690  const char *mime_type);
2691 
2692 /**
2693  * Guess the codec ID based upon muxer and filename.
2694  */
2695 enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
2696  const char *filename, const char *mime_type,
2697  enum AVMediaType type);
2698 
2699 /**
2700  * Get timing information for the data currently output.
2701  * The exact meaning of "currently output" depends on the format.
2702  * It is mostly relevant for devices that have an internal buffer and/or
2703  * work in real time.
2704  * @param s media file handle
2705  * @param stream stream in the media file
2706  * @param[out] dts DTS of the last packet output for the stream, in stream
2707  * time_base units
2708  * @param[out] wall absolute time when that packet whas output,
2709  * in microsecond
2710  * @return 0 if OK, AVERROR(ENOSYS) if the format does not support it
2711  * Note: some formats or devices may not allow to measure dts and wall
2712  * atomically.
2713  */
2714 int av_get_output_timestamp(struct AVFormatContext *s, int stream,
2715  int64_t *dts, int64_t *wall);
2716 
2717 
2718 /**
2719  * @}
2720  */
2721 
2722 
2723 /**
2724  * @defgroup lavf_misc Utility functions
2725  * @ingroup libavf
2726  * @{
2727  *
2728  * Miscellaneous utility functions related to both muxing and demuxing
2729  * (or neither).
2730  */
2731 
2732 /**
2733  * Send a nice hexadecimal dump of a buffer to the specified file stream.
2734  *
2735  * @param f The file stream pointer where the dump should be sent to.
2736  * @param buf buffer
2737  * @param size buffer size
2738  *
2739  * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2
2740  */
2741 void av_hex_dump(FILE *f, const uint8_t *buf, int size);
2742 
2743 /**
2744  * Send a nice hexadecimal dump of a buffer to the log.
2745  *
2746  * @param avcl A pointer to an arbitrary struct of which the first field is a
2747  * pointer to an AVClass struct.
2748  * @param level The importance level of the message, lower values signifying
2749  * higher importance.
2750  * @param buf buffer
2751  * @param size buffer size
2752  *
2753  * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2
2754  */
2755 void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size);
2756 
2757 /**
2758  * Send a nice dump of a packet to the specified file stream.
2759  *
2760  * @param f The file stream pointer where the dump should be sent to.
2761  * @param pkt packet to dump
2762  * @param dump_payload True if the payload must be displayed, too.
2763  * @param st AVStream that the packet belongs to
2764  */
2765 void av_pkt_dump2(FILE *f, const AVPacket *pkt, int dump_payload, const AVStream *st);
2766 
2767 
2768 /**
2769  * Send a nice dump of a packet to the log.
2770  *
2771  * @param avcl A pointer to an arbitrary struct of which the first field is a
2772  * pointer to an AVClass struct.
2773  * @param level The importance level of the message, lower values signifying
2774  * higher importance.
2775  * @param pkt packet to dump
2776  * @param dump_payload True if the payload must be displayed, too.
2777  * @param st AVStream that the packet belongs to
2778  */
2779 void av_pkt_dump_log2(void *avcl, int level, const AVPacket *pkt, int dump_payload,
2780  const AVStream *st);
2781 
2782 /**
2783  * Get the AVCodecID for the given codec tag tag.
2784  * If no codec id is found returns AV_CODEC_ID_NONE.
2785  *
2786  * @param tags list of supported codec_id-codec_tag pairs, as stored
2787  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2788  * @param tag codec tag to match to a codec ID
2789  */
2790 enum AVCodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
2791 
2792 /**
2793  * Get the codec tag for the given codec id id.
2794  * If no codec tag is found returns 0.
2795  *
2796  * @param tags list of supported codec_id-codec_tag pairs, as stored
2797  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2798  * @param id codec ID to match to a codec tag
2799  */
2800 unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id);
2801 
2802 /**
2803  * Get the codec tag for the given codec id.
2804  *
2805  * @param tags list of supported codec_id - codec_tag pairs, as stored
2806  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2807  * @param id codec id that should be searched for in the list
2808  * @param tag A pointer to the found tag
2809  * @return 0 if id was not found in tags, > 0 if it was found
2810  */
2811 int av_codec_get_tag2(const struct AVCodecTag * const *tags, enum AVCodecID id,
2812  unsigned int *tag);
2813 
2815 
2816 /**
2817  * Get the index for a specific timestamp.
2818  *
2819  * @param st stream that the timestamp belongs to
2820  * @param timestamp timestamp to retrieve the index for
2821  * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
2822  * to the timestamp which is <= the requested one, if backward
2823  * is 0, then it will be >=
2824  * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
2825  * @return < 0 if no such timestamp could be found
2826  */
2827 int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
2828 
2829 /**
2830  * Add an index entry into a sorted list. Update the entry if the list
2831  * already contains it.
2832  *
2833  * @param timestamp timestamp in the time base of the given stream
2834  */
2835 int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
2836  int size, int distance, int flags);
2837 
2838 
2839 /**
2840  * Split a URL string into components.
2841  *
2842  * The pointers to buffers for storing individual components may be null,
2843  * in order to ignore that component. Buffers for components not found are
2844  * set to empty strings. If the port is not found, it is set to a negative
2845  * value.
2846  *
2847  * @param proto the buffer for the protocol
2848  * @param proto_size the size of the proto buffer
2849  * @param authorization the buffer for the authorization
2850  * @param authorization_size the size of the authorization buffer
2851  * @param hostname the buffer for the host name
2852  * @param hostname_size the size of the hostname buffer
2853  * @param port_ptr a pointer to store the port number in
2854  * @param path the buffer for the path
2855  * @param path_size the size of the path buffer
2856  * @param url the URL to split
2857  */
2858 void av_url_split(char *proto, int proto_size,
2859  char *authorization, int authorization_size,
2860  char *hostname, int hostname_size,
2861  int *port_ptr,
2862  char *path, int path_size,
2863  const char *url);
2864 
2865 
2866 /**
2867  * Print detailed information about the input or output format, such as
2868  * duration, bitrate, streams, container, programs, metadata, side data,
2869  * codec and time base.
2870  *
2871  * @param ic the context to analyze
2872  * @param index index of the stream to dump information about
2873  * @param url the URL to print, such as source or destination file
2874  * @param is_output Select whether the specified context is an input(0) or output(1)
2875  */
2877  int index,
2878  const char *url,
2879  int is_output);
2880 
2881 
2882 #define AV_FRAME_FILENAME_FLAGS_MULTIPLE 1 ///< Allow multiple %d
2883 
2884 /**
2885  * Return in 'buf' the path with '%d' replaced by a number.
2886  *
2887  * Also handles the '%0nd' format where 'n' is the total number
2888  * of digits and '%%'.
2889  *
2890  * @param buf destination buffer
2891  * @param buf_size destination buffer size
2892  * @param path numbered sequence string
2893  * @param number frame number
2894  * @param flags AV_FRAME_FILENAME_FLAGS_*
2895  * @return 0 if OK, -1 on format error
2896  */
2897 int av_get_frame_filename2(char *buf, int buf_size,
2898  const char *path, int number, int flags);
2899 
2900 int av_get_frame_filename(char *buf, int buf_size,
2901  const char *path, int number);
2902 
2903 /**
2904  * Check whether filename actually is a numbered sequence generator.
2905  *
2906  * @param filename possible numbered sequence string
2907  * @return 1 if a valid numbered sequence string, 0 otherwise
2908  */
2909 int av_filename_number_test(const char *filename);
2910 
2911 /**
2912  * Generate an SDP for an RTP session.
2913  *
2914  * Note, this overwrites the id values of AVStreams in the muxer contexts
2915  * for getting unique dynamic payload types.
2916  *
2917  * @param ac array of AVFormatContexts describing the RTP streams. If the
2918  * array is composed by only one context, such context can contain
2919  * multiple AVStreams (one AVStream per RTP stream). Otherwise,
2920  * all the contexts in the array (an AVCodecContext per RTP stream)
2921  * must contain only one AVStream.
2922  * @param n_files number of AVCodecContexts contained in ac
2923  * @param buf buffer where the SDP will be stored (must be allocated by
2924  * the caller)
2925  * @param size the size of the buffer
2926  * @return 0 if OK, AVERROR_xxx on error
2927  */
2928 int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size);
2929 
2930 /**
2931  * Return a positive value if the given filename has one of the given
2932  * extensions, 0 otherwise.
2933  *
2934  * @param filename file name to check against the given extensions
2935  * @param extensions a comma-separated list of filename extensions
2936  */
2937 int av_match_ext(const char *filename, const char *extensions);
2938 
2939 /**
2940  * Test if the given container can store a codec.
2941  *
2942  * @param ofmt container to check for compatibility
2943  * @param codec_id codec to potentially store in container
2944  * @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
2945  *
2946  * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
2947  * A negative number if this information is not available.
2948  */
2950  int std_compliance);
2951 
2952 /**
2953  * @defgroup riff_fourcc RIFF FourCCs
2954  * @{
2955  * Get the tables mapping RIFF FourCCs to libavcodec AVCodecIDs. The tables are
2956  * meant to be passed to av_codec_get_id()/av_codec_get_tag() as in the
2957  * following code:
2958  * @code
2959  * uint32_t tag = MKTAG('H', '2', '6', '4');
2960  * const struct AVCodecTag *table[] = { avformat_get_riff_video_tags(), 0 };
2961  * enum AVCodecID id = av_codec_get_id(table, tag);
2962  * @endcode
2963  */
2964 /**
2965  * @return the table mapping RIFF FourCCs for video to libavcodec AVCodecID.
2966  */
2967 const struct AVCodecTag *avformat_get_riff_video_tags(void);
2968 /**
2969  * @return the table mapping RIFF FourCCs for audio to AVCodecID.
2970  */
2971 const struct AVCodecTag *avformat_get_riff_audio_tags(void);
2972 /**
2973  * @return the table mapping MOV FourCCs for video to libavcodec AVCodecID.
2974  */
2975 const struct AVCodecTag *avformat_get_mov_video_tags(void);
2976 /**
2977  * @return the table mapping MOV FourCCs for audio to AVCodecID.
2978  */
2979 const struct AVCodecTag *avformat_get_mov_audio_tags(void);
2980 
2981 /**
2982  * @}
2983  */
2984 
2985 /**
2986  * Guess the sample aspect ratio of a frame, based on both the stream and the
2987  * frame aspect ratio.
2988  *
2989  * Since the frame aspect ratio is set by the codec but the stream aspect ratio
2990  * is set by the demuxer, these two may not be equal. This function tries to
2991  * return the value that you should use if you would like to display the frame.
2992  *
2993  * Basic logic is to use the stream aspect ratio if it is set to something sane
2994  * otherwise use the frame aspect ratio. This way a container setting, which is
2995  * usually easy to modify can override the coded value in the frames.
2996  *
2997  * @param format the format context which the stream is part of
2998  * @param stream the stream which the frame is part of
2999  * @param frame the frame with the aspect ratio to be determined
3000  * @return the guessed (valid) sample_aspect_ratio, 0/1 if no idea
3001  */
3003 
3004 /**
3005  * Guess the frame rate, based on both the container and codec information.
3006  *
3007  * @param ctx the format context which the stream is part of
3008  * @param stream the stream which the frame is part of
3009  * @param frame the frame for which the frame rate should be determined, may be NULL
3010  * @return the guessed (valid) frame rate, 0/1 if no idea
3011  */
3013 
3014 /**
3015  * Check if the stream st contained in s is matched by the stream specifier
3016  * spec.
3017  *
3018  * See the "stream specifiers" chapter in the documentation for the syntax
3019  * of spec.
3020  *
3021  * @return >0 if st is matched by spec;
3022  * 0 if st is not matched by spec;
3023  * AVERROR code if spec is invalid
3024  *
3025  * @note A stream specifier can match several streams in the format.
3026  */
3028  const char *spec);
3029 
3031 
3032 #if FF_API_OLD_BSF
3033 /**
3034  * Apply a list of bitstream filters to a packet.
3035  *
3036  * @param codec AVCodecContext, usually from an AVStream
3037  * @param pkt the packet to apply filters to. If, on success, the returned
3038  * packet has size == 0 and side_data_elems == 0, it indicates that
3039  * the packet should be dropped
3040  * @param bsfc a NULL-terminated list of filters to apply
3041  * @return >=0 on success;
3042  * AVERROR code on failure
3043  */
3045 int av_apply_bitstream_filters(AVCodecContext *codec, AVPacket *pkt,
3046  AVBitStreamFilterContext *bsfc);
3047 #endif
3048 
3049 enum AVTimebaseSource {
3050  AVFMT_TBCF_AUTO = -1,
3053 #if FF_API_R_FRAME_RATE
3054  AVFMT_TBCF_R_FRAMERATE,
3055 #endif
3056 };
3057 
3058 /**
3059  * Transfer internal timing information from one stream to another.
3060  *
3061  * This function is useful when doing stream copy.
3062  *
3063  * @param ofmt target output format for ost
3064  * @param ost output stream which needs timings copy and adjustments
3065  * @param ist reference input stream to copy timings from
3066  * @param copy_tb define from where the stream codec timebase needs to be imported
3067  */
3069  AVStream *ost, const AVStream *ist,
3070  enum AVTimebaseSource copy_tb);
3071 
3072 /**
3073  * Get the internal codec timebase from a stream.
3074  *
3075  * @param st input stream to extract the timebase from
3076  */
3078 
3079 /**
3080  * @}
3081  */
3082 
3083 #endif /* AVFORMAT_AVFORMAT_H */
unsigned int nb_chapters
Number of chapters in AVChapter array.
Definition: avformat.h:1578
unsigned int max_index_size
Maximum amount of memory in bytes to use for the index of each stream.
Definition: avformat.h:1559
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:4707
int64_t interleaver_chunk_size
Definition: avformat.h:1122
int64_t probesize
Maximum size of the data read from input for determining the input container format.
Definition: avformat.h:1515
unsigned int packet_size
Definition: avformat.h:1475
int64_t first_dts
Timestamp corresponding to the last dts sync point.
Definition: avformat.h:1076
full parsing and interpolation of timestamps for frames not starting on a packet boundary ...
Definition: avformat.h:795
int64_t duration_gcd
Definition: avformat.h:1039
int audio_preload
Audio preload in microseconds.
Definition: avformat.h:1697
Bytestream IO Context.
Definition: avio.h:161
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
int pmt_stream_idx
Definition: avformat.h:1120
AVProbeData probe_data
Definition: avformat.h:1099
Buffered I/O operations.
AVPacketSideDataType
Definition: avcodec.h:1143
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:1602
static const char * format[]
Definition: af_aiir.c:311
attribute_deprecated int av_demuxer_open(AVFormatContext *ic)
Definition: utils.c:395
This structure describes decoded (raw) audio or video data.
Definition: frame.h:218
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:746
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file ensuring correct interleaving.
Definition: mux.c:1185
int pmt_version
Definition: avformat.h:1119
AVIOInterruptCB interrupt_callback
Custom interrupt callbacks for the I/O layer.
Definition: avformat.h:1627
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
static void flush(AVCodecContext *avctx)
int(* init)(struct AVFormatContext *)
Initialize format.
Definition: avformat.h:617
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:2038
int flush_packets
Flush the I/O context after each packet.
Definition: avformat.h:1764
int av_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file.
Definition: mux.c:878
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:1736
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:1151
void(* deinit)(struct AVFormatContext *)
Deinitialize format.
Definition: avformat.h:626
const char * filename
Definition: avformat.h:449
int64_t pts_buffer[MAX_REORDER_DELAY+1]
Definition: avformat.h:1101
unsigned int max_picture_buffer
Maximum amount of memory in bytes to use for buffering frames obtained from realtime capture devices...
Definition: avformat.h:1565
int64_t pos
Definition: avformat.h:803
int probe_packets
Number of packets to buffer for codec probing.
Definition: avformat.h:1084
int event_flags
Flags for the user to detect events happening on the stream.
Definition: avformat.h:987
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:5001
enum AVCodecID video_codec
default video codec
Definition: avformat.h:518
int64_t first_discard_sample
If not 0, the first audio sample that should be discarded from the stream.
Definition: avformat.h:1159
int64_t pts_wrap_reference
Internal data to check for wrapping of the time stamp.
Definition: avformat.h:1183
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:936
uint8_t * dump_separator
dump format separator.
Definition: avformat.h:1874
int index
stream index in AVFormatContext
Definition: avformat.h:875
int avio_flags
avio flags, used to force AVIO_FLAG_DIRECT.
Definition: avformat.h:1728
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1103
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:632
int(* free_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps)
Free device capabilities submodule.
Definition: avformat.h:606
int64_t bit_rate
Total stream bitrate in bit/s, 0 if not available.
Definition: avformat.h:1473
int event_flags
Flags for the user to detect events happening on the file.
Definition: avformat.h:1664
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:1302
void * priv_data
Definition: avformat.h:889
AVInputFormat * av_probe_input_format3(AVProbeData *pd, int is_opened, int *score_ret)
Guess the file format.
Definition: format.c:128
int(* write_packet)(struct AVFormatContext *, AVPacket *pkt)
Write a packet.
Definition: avformat.h:558
AVPacketSideData * side_data
An array of side data that applies to the whole stream (i.e.
Definition: avformat.h:976
int pmt_version
Definition: avformat.h:1279
static AVPacket pkt
int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index)
Test whether a muxer supports uncoded frame.
Definition: mux.c:1379
int priv_data_size
Size of private data so that it can be allocated in the wrapper.
Definition: avformat.h:698
int ctx_flags
Flags signalling stream properties.
Definition: avformat.h:1400
AVDictionary * metadata
Definition: avformat.h:1312
enum AVCodecID subtitle_codec_id
Forced subtitle codec_id.
Definition: avformat.h:1547
AVCodec.
Definition: avcodec.h:3408
int strict_std_compliance
Allow non-standard and experimental extension.
Definition: avformat.h:1657
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3876
enum AVDurationEstimationMethod av_fmt_ctx_get_duration_estimation_method(const AVFormatContext *ctx)
Returns the method used to set ctx->duration.
Definition: options.c:163
int64_t last_dts_for_order_check
Internal data to analyze DTS and detect faulty mpeg streams.
Definition: avformat.h:1211
Format I/O context.
Definition: avformat.h:1351
int64_t output_ts_offset
Output timestamp offset, in microseconds.
Definition: avformat.h:1866
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:5024
unsigned int nb_stream_indexes
Definition: avformat.h:1273
int64_t cur_dts
Definition: avformat.h:1077
const struct AVCodecTag * avformat_get_mov_audio_tags(void)
Definition: isom.c:652
Public dictionary API.
int flags
Definition: avformat.h:1270
int(* read_close)(struct AVFormatContext *)
Close the stream.
Definition: avformat.h:729
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:526
uint8_t
int stream_identifier
Stream Identifier This is the MPEG-TS stream identifier +1 0 means unknown.
Definition: avformat.h:1113
const struct AVCodecTag * avformat_get_riff_video_tags(void)
Definition: riff.c:576
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:661
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:66
const char * avformat_license(void)
Return the libavformat license.
Definition: utils.c:77
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:5701
int(* free_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps)
Free device capabilities submodule.
Definition: avformat.h:785
AVPacket pkt
Definition: avformat.h:2016
#define f(width, name)
Definition: cbs_vp9.c:255
int priv_data_size
size of private data so that it can be allocated in the wrapper
Definition: avformat.h:548
int id
unique ID to identify the chapter
Definition: avformat.h:1309
enum AVStreamParseType need_parsing
Definition: avformat.h:1092
int id
Format-specific stream ID.
Definition: avformat.h:881
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:5045
int duration_count
Definition: avformat.h:1040
int nb_side_data
The number of elements in the AVStream.side_data array.
Definition: avformat.h:980
AVDurationEstimationMethod
The duration of a video can be estimated through various ways, and this enum can be used to know how ...
Definition: avformat.h:1329
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4456
int pmt_pid
Definition: avformat.h:1277
uint8_t * av_stream_get_side_data(const AVStream *stream, enum AVPacketSideDataType type, int *size)
Get side information from stream.
Definition: utils.c:5421
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1419
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:144
int inject_global_side_data
Internal data to inject global side data.
Definition: avformat.h:1218
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:72
#define MAX_REORDER_DELAY
Definition: avformat.h:1100
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:672
int64_t last_duration
Definition: avformat.h:1054
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1482
AVProgram * av_new_program(AVFormatContext *s, int id)
Definition: utils.c:4555
char * protocol_whitelist
',' separated list of allowed protocols.
Definition: avformat.h:1909
int(* read_header)(struct AVFormatContext *)
Read the format header and initialize the AVFormatContext structure.
Definition: avformat.h:712
int64_t max_interleave_delta
Maximum buffering duration for interleaving.
Definition: avformat.h:1651
uint32_t tag
Definition: movenc.c:1455
int avformat_network_init(void)
Do global initialization of network libraries.
Definition: utils.c:4938
const struct AVCodecTag * avformat_get_riff_audio_tags(void)
Definition: riff.c:581
int fps_probe_size
The number of frames used for determining the framerate in avformat_find_stream_info().
Definition: avformat.h:1609
int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size)
Generate an SDP for an RTP session.
Definition: sdp.c:841
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:310
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:38
const AVClass * avformat_get_class(void)
Get the AVClass for AVFormatContext.
Definition: options.c:168
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:222
#define flags(name, subs,...)
Definition: cbs_h2645.c:263
enum AVDiscard discard
selects which program to discard and which to feed to the caller
Definition: avformat.h:1271
unsigned int * stream_index
Definition: avformat.h:1272
enum AVCodecID video_codec_id
Forced video codec_id.
Definition: avformat.h:1535
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:797
int64_t rfps_duration_sum
Definition: avformat.h:1041
Duration estimated from bitrate (less accurate)
Definition: avformat.h:1332
int av_append_packet(AVIOContext *s, AVPacket *pkt, int size)
Read data and append it to the current content of the AVPacket.
Definition: utils.c:320
unsigned int correct_ts_overflow
Correct single timestamp overflows.
Definition: avformat.h:1750
struct AVOutputFormat * oformat
The output container format.
Definition: avformat.h:1370
int64_t start_time
Definition: avformat.h:1288
const AVOutputFormat * av_muxer_iterate(void **opaque)
Iterate over all registered muxers.
Definition: allformats.c:493
const struct AVCodecTag * avformat_get_mov_video_tags(void)
Definition: isom.c:647
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:563
Callback for checking whether to abort blocking functions.
Definition: avio.h:58
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:4184
AVRational av_stream_get_codec_timebase(const AVStream *st)
Get the internal codec timebase from a stream.
Definition: utils.c:5763
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:312
int(* write_uncoded_frame)(struct AVFormatContext *, int stream_index, AVFrame **frame, unsigned flags)
Write an uncoded AVFrame.
Definition: avformat.h:590
AVProgram * av_find_program_from_stream(AVFormatContext *ic, AVProgram *last, int s)
Find the programs which belong to a given stream.
Definition: utils.c:4167
int max_ts_probe
Maximum number of packets to read while waiting for the first timestamp.
Definition: avformat.h:1671
int format_probesize
number of bytes to read maximally to identify format.
Definition: avformat.h:1780
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:215
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1589
int nb_decoded_frames
Number of internally decoded frames, used internally in libavformat, do not access its lifetime diffe...
Definition: avformat.h:1172
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2147
const AVIOInterruptCB int_cb
Definition: ffmpeg.c:481
int(* read_probe)(AVProbeData *)
Tell if a given file has a chance of being parsed as this format.
Definition: avformat.h:705
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:1291
const char * long_name
Descriptive name for the format, meant to be more human-readable than name.
Definition: avformat.h:513
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:804
int(* query_codec)(enum AVCodecID id, int std_compliance)
Test if the given codec can be stored in this container.
Definition: avformat.h:572
int(* write_header)(struct AVFormatContext *)
Definition: avformat.h:550
char * url
input or output URL.
Definition: avformat.h:1447
const char * r
Definition: vf_curves.c:111
struct AVCodecParserContext * av_stream_get_parser(const AVStream *s)
Definition: utils.c:149
unsigned int nb_programs
Definition: avformat.h:1528
int last_IP_duration
Definition: avformat.h:1079
int av_read_play(AVFormatContext *s)
Start playing a network-based stream (e.g.
Definition: utils.c:4251
AVChapter ** chapters
Definition: avformat.h:1579
int skip_estimate_duration_from_pts
Skip duration calcuation in estimate_timings_from_pts.
Definition: avformat.h:1958
int skip_samples
Number of samples to skip at the start of the frame decoded from the next packet. ...
Definition: avformat.h:1142
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:947
New fields can be added to the end with minor version bumps.
Definition: avformat.h:1268
AVInputFormat * av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max)
Guess the file format.
Definition: format.c:205
int min_distance
Minimum distance between this and the previous keyframe, used to avoid unneeded searching.
Definition: avformat.h:816
int program_num
Definition: avformat.h:1276
AVCodec * audio_codec
Forced audio codec.
Definition: avformat.h:1826
void * opaque
User data.
Definition: avformat.h:1855
Only parse headers, do not repack.
Definition: avformat.h:794
char * format_whitelist
',' separated list of allowed demuxers.
Definition: avformat.h:1796
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:4920
static float distance(float x, float y, int band)
const char * mime_type
mime_type, when known.
Definition: avformat.h:452
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:451
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
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:154
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1407
int64_t fps_first_dts
Those are used for average framerate estimation.
Definition: avformat.h:1059
int av_read_pause(AVFormatContext *s)
Pause a network-based stream (e.g.
Definition: utils.c:4260
AVInputFormat * av_find_input_format(const char *short_name)
Find AVInputFormat based on the short name of the input format.
Definition: format.c:118
static void callback(void *priv_data, int index, uint8_t *buf, int buf_size, int64_t time, enum dshowDeviceType devtype)
Definition: dshow.c:161
struct AVStream::@217 * info
Stream information used internally by avformat_find_stream_info()
int update_initial_durations_done
Internal data to prevent doing update_initial_durations() twice.
Definition: avformat.h:1200
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:508
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:1541
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:5436
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:87
int max_streams
The maximum number of streams.
Definition: avformat.h:1951
typedef void(APIENTRY *FF_PFNGLACTIVETEXTUREPROC)(GLenum texture)
int av_find_default_stream_index(AVFormatContext *s)
Definition: utils.c:1879
int frame_delay_evidence
Definition: avformat.h:1045
const char * name
Definition: avformat.h:507
Duration estimated from a stream with a known duration.
Definition: avformat.h:1331
AVFormatContext * ctx
Definition: movenc.c:48
uint8_t dts_ordered
Definition: avformat.h:1212
#define s(width, name)
Definition: cbs_vp9.c:257
int avoid_negative_ts
Avoid negative timestamps during muxing.
Definition: avformat.h:1680
int(* control_message)(struct AVFormatContext *s, int type, void *data, size_t data_size)
Allows sending messages from application to device.
Definition: avformat.h:579
AVDictionary * metadata
Definition: avformat.h:938
uint8_t * av_stream_new_side_data(AVStream *stream, enum AVPacketSideDataType type, int size)
Allocate new information from stream.
Definition: utils.c:5472
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:51
int probe_score
format probing score.
Definition: avformat.h:1773
enum AVCodecID codec_id
Definition: vaapi_decode.c:362
Libavformat version macros.
int64_t skip_initial_bytes
Skip initial bytes when opening stream.
Definition: avformat.h:1743
void(* get_output_timestamp)(struct AVFormatContext *s, int stream, int64_t *dts, int64_t *wall)
Definition: avformat.h:574
int(* read_pause)(struct AVFormatContext *)
Pause playing - only meaningful if using a network-based format (RTSP).
Definition: avformat.h:759
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:535
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:488
int program_num
Details of the MPEG-TS program which created this stream.
Definition: avformat.h:1118
const AVInputFormat * av_demuxer_iterate(void **opaque)
Iterate over all registered demuxers.
Definition: allformats.c:510
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:1523
int(* get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list)
Returns device list with it properties.
Definition: avformat.h:596
int av_get_frame_filename(char *buf, int buf_size, const char *path, int number)
Definition: utils.c:4702
uint8_t pts_reorder_error_count[MAX_REORDER_DELAY+1]
Definition: avformat.h:1206
int ts_id
Transport stream id.
Definition: avformat.h:1689
const char * long_name
Descriptive name for the format, meant to be more human-readable than name.
Definition: avformat.h:654
int metadata_header_padding
Number of bytes to be written as padding in a metadata header.
Definition: avformat.h:1849
Stream structure.
Definition: avformat.h:874
int(* create_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps)
Initialize device capabilities submodule.
Definition: avformat.h:601
int64_t end
chapter start/end time in time_base units
Definition: avformat.h:1311
int avformat_queue_attached_pictures(AVFormatContext *s)
Definition: utils.c:479
int avformat_network_deinit(void)
Undo the initialization done by avformat_network_init.
Definition: utils.c:4950
uint8_t dts_misordered
Definition: avformat.h:1213
int64_t pts_reorder_error[MAX_REORDER_DELAY+1]
Internal data to generate dts from pts.
Definition: avformat.h:1205
int64_t end_time
Definition: avformat.h:1289
Libavcodec external API header.
struct AVOutputFormat * next
Definition: avformat.h:544
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:739
int debug
Flags to enable debugging.
Definition: avformat.h:1632
AVIOContext * pb
I/O context.
Definition: avformat.h:1393
const struct AVCodecTag *const * codec_tag
List of supported codec_id-codec_tag pairs, ordered by "better choice first".
Definition: avformat.h:532
main external API structure.
Definition: avcodec.h:1518
int io_repositioned
IO repositioned flag.
Definition: avformat.h:1810
int av_filename_number_test(const char *filename)
Check whether filename actually is a numbered sequence generator.
Definition: utils.c:327
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:723
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:4647
int pts_wrap_behavior
behavior on wrap detection
Definition: avformat.h:1292
void * buf
Definition: avisynth_c.h:690
double(* duration_error)[2][MAX_STD_TIMEBASES]
Definition: avformat.h:1042
GLint GLenum type
Definition: opengl_enc.c:105
int nb_index_entries
Definition: avformat.h:1105
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:779
enum AVCodecID subtitle_codec
default subtitle codec
Definition: avformat.h:519
Rational number (pair of numerator and denominator).
Definition: rational.h:58
int64_t last_dts
Definition: avformat.h:1038
AVRational display_aspect_ratio
display aspect ratio (0 if unknown)
Definition: avformat.h:1225
const AVClass * av_class
A class for logging and AVOptions.
Definition: avformat.h:1356
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:563
int64_t fps_last_dts
Definition: avformat.h:1061
int found_decoder
0 -> decoder has not been searched for yet.
Definition: avformat.h:1052
void avformat_free_context(AVFormatContext *s)
Free an AVFormatContext and all its streams.
Definition: utils.c:4390
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: utils.c:1767
List of devices.
Definition: avdevice.h:460
AVTimebaseSource
Definition: avformat.h:3063
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:2528
int seek2any
Force seeking to any (also non key) frames.
Definition: avformat.h:1757
full parsing and repack of the first frame only, only implemented for H.264 currently ...
Definition: avformat.h:796
int raw_codec_id
Raw demuxers store their codec ID here.
Definition: avformat.h:693
AVDictionary * metadata
Definition: avformat.h:1274
int64_t codec_info_duration
Definition: avformat.h:1043
int fps_first_dts_idx
Definition: avformat.h:1060
int64_t start_time
Position of the first frame of the component, in AV_TIME_BASE fractional seconds. ...
Definition: avformat.h:1456
const char * mime_type
Comma-separated list of mime types.
Definition: avformat.h:679
uint8_t level
Definition: svq3.c:207
#define attribute_deprecated
Definition: attributes.h:94
Duration accurately estimated from PTSes.
Definition: avformat.h:1330
#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:2505
int64_t start
Definition: avformat.h:1311
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:923
int64_t interleaver_chunk_duration
Definition: avformat.h:1123
const char * extensions
If extensions are defined, then no probe is done.
Definition: avformat.h:668
const uint8_t * key
Definition: avformat.h:1525
full parsing and repack
Definition: avformat.h:793
static AVStream * ost
int
const OptionDef options[]
Definition: ffmpeg_opt.c:3294
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:1373
struct AVPacketList * next
Definition: avformat.h:2017
int pts_wrap_behavior
Options for behavior, when a wrap is detected.
Definition: avformat.h:1195
int(* read_play)(struct AVFormatContext *)
Start/resume playing - only meaningful if using a network-based format (RTSP).
Definition: avformat.h:753
enum AVCodecID data_codec
default data codec
Definition: avformat.h:607
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
Definition: utils.c:3565
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:913
AVCodec * video_codec
Forced video codec.
Definition: avformat.h:1818
static double c[64]
int max_chunk_size
Max chunk size in bytes Note, not all formats support this and unpredictable things may happen if it ...
Definition: avformat.h:1713
int error_recognition
Error recognition; higher values will detect more errors but may misdetect some more or less valid pa...
Definition: avformat.h:1616
int disposition
AV_DISPOSITION_* bit field.
Definition: avformat.h:927
AVStreamParseType
Definition: avformat.h:791
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:1319
int pts_wrap_bits
number of bits in pts (used for wrapping control)
Definition: avformat.h:1066
AVRational time_base
time base in which the start/end timestamps are specified
Definition: avformat.h:1310
av_format_control_message control_message_cb
Callback used by devices to communicate with application.
Definition: avformat.h:1860
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:925
struct AVInputFormat * iformat
The input container format.
Definition: avformat.h:1363
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: utils.c:4428
int av_write_uncoded_frame(AVFormatContext *s, int stream_index, AVFrame *frame)
Write an uncoded frame to an output media file.
Definition: mux.c:1367
int64_t codec_info_duration_fields
Definition: avformat.h:1044
unsigned int index_entries_allocated_size
Definition: avformat.h:1106
int64_t mux_ts_offset
Timestamp offset added to timestamps before muxing NOT PART OF PUBLIC API.
Definition: avformat.h:1178
int skip_to_keyframe
Indicates that everything up to the next keyframe should be discarded.
Definition: avformat.h:1137
enum AVCodecID data_codec_id
Forced Data codec_id.
Definition: avformat.h:1880
AVCodec * subtitle_codec
Forced subtitle codec.
Definition: avformat.h:1834
int(* AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options)
Definition: avformat.h:1322
AVCodec * data_codec
Forced data codec.
Definition: avformat.h:1842
enum AVCodecID audio_codec
default audio codec
Definition: avformat.h:517
char * codec_whitelist
',' separated list of allowed decoders.
Definition: avformat.h:1788
int(* get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list)
Returns device list with it properties.
Definition: avformat.h:773
int max_chunk_duration
Max chunk time in microseconds.
Definition: avformat.h:1705
struct AVCodecParserContext * parser
Definition: avformat.h:1093
void * priv_data
Format private data.
Definition: avformat.h:1379
int pcr_pid
Definition: avformat.h:1278
int codec_info_nb_frames
Number of frames that have been demuxed during avformat_find_stream_info()
Definition: avformat.h:1089
int avformat_open_input(AVFormatContext **ps, const char *url, AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: utils.c:537
AVDiscard
Definition: avcodec.h:785
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
Definition: mux.c:1247
char * protocol_blacklist
',' separated list of disallowed protocols.
Definition: avformat.h:1944
int64_t duration
Duration of the stream, in AV_TIME_BASE fractional seconds.
Definition: avformat.h:1466
int avformat_flush(AVFormatContext *s)
Discard all internally buffered data.
Definition: utils.c:2585
FILE * out
Definition: movenc.c:54
int64_t last_IP_pts
Definition: avformat.h:1078
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:767
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
static int format_name(char *buf, int buf_len, int index)
Definition: hlsenc.c:1744
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1021
int copy_tb
Definition: ffmpeg_opt.c:101
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:1062
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:903
struct AVInputFormat * next
Definition: avformat.h:688
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:515
enum AVDiscard discard
Selects which packets can be discarded at will and do not need to be demuxed.
Definition: avformat.h:929
AVRational r_frame_rate
Real base framerate of the stream.
Definition: avformat.h:998
int(* io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags, AVDictionary **options)
A callback for opening new IO streams.
Definition: avformat.h:1931
AVInputFormat * av_probe_input_format(AVProbeData *pd, int is_opened)
Guess the file format.
Definition: format.c:216
const char * mime_type
Definition: avformat.h:514
int request_probe
stream probing state -1 -> probing finished 0 -> no probing requested rest -> perform probing with re...
Definition: avformat.h:1132
enum AVCodecID id
Following API allows user to probe device capabilities (supported codecs, pixel formats, sample formats, resolutions, channel counts, etc).
Definition: avdevice.h:400
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:1721
This structure stores compressed data.
Definition: avcodec.h:1407
int(* write_trailer)(struct AVFormatContext *)
Definition: avformat.h:559
void(* io_close)(struct AVFormatContext *s, AVIOContext *pb)
A callback for closing the streams opened with AVFormatContext.io_open().
Definition: avformat.h:1937
#define MAX_STD_TIMEBASES
Definition: avformat.h:1033
const struct AVCodecTag *const * codec_tag
Definition: avformat.h:670
int64_t av_stream_get_end_pts(const AVStream *st)
Returns the pts of the last muxed packet + its duration.
Definition: utils.c:141
AVPacket attached_pic
For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet will contain the attached pictu...
Definition: avformat.h:956
struct AVPacketList * last_in_packet_buffer
last packet in packet_buffer for this stream when muxing.
Definition: avformat.h:1098
int64_t last_discard_sample
The sample after last sample that is intended to be discarded after first_discard_sample.
Definition: avformat.h:1166
AVProgram ** programs
Definition: avformat.h:1529