FFmpeg 7.1.1
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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).
40 * Unless you are absolutely sure you won't use libavformat's network
41 * capabilities, you should also call avformat_network_init().
42 *
43 * A supported input format is described by an AVInputFormat struct, conversely
44 * an output format is described by AVOutputFormat. You can iterate over all
45 * input/output formats using the av_demuxer_iterate / av_muxer_iterate() functions.
46 * The protocols layer is not part of the public API, so you can only get the names
47 * of supported protocols with the avio_enum_protocols() function.
48 *
49 * Main lavf structure used for both muxing and demuxing is AVFormatContext,
50 * which exports all information about the file being read or written. As with
51 * most Libavformat structures, its size is not part of public ABI, so it cannot be
52 * allocated on stack or directly with av_malloc(). To create an
53 * AVFormatContext, use avformat_alloc_context() (some functions, like
54 * avformat_open_input() might do that for you).
55 *
56 * Most importantly an AVFormatContext contains:
57 * @li the @ref AVFormatContext.iformat "input" or @ref AVFormatContext.oformat
58 * "output" format. It is either autodetected or set by user for input;
59 * always set by user for output.
60 * @li an @ref AVFormatContext.streams "array" of AVStreams, which describe all
61 * elementary streams stored in the file. AVStreams are typically referred to
62 * using their index in this array.
63 * @li an @ref AVFormatContext.pb "I/O context". It is either opened by lavf or
64 * set by user for input, always set by user for output (unless you are dealing
65 * with an AVFMT_NOFILE format).
66 *
67 * @section lavf_options Passing options to (de)muxers
68 * It is possible to configure lavf muxers and demuxers using the @ref avoptions
69 * mechanism. Generic (format-independent) libavformat options are provided by
70 * AVFormatContext, they can be examined from a user program by calling
71 * av_opt_next() / av_opt_find() on an allocated AVFormatContext (or its AVClass
72 * from avformat_get_class()). Private (format-specific) options are provided by
73 * AVFormatContext.priv_data if and only if AVInputFormat.priv_class /
74 * AVOutputFormat.priv_class of the corresponding format struct is non-NULL.
75 * Further options may be provided by the @ref AVFormatContext.pb "I/O context",
76 * if its AVClass is non-NULL, and the protocols layer. See the discussion on
77 * nesting in @ref avoptions documentation to learn how to access those.
78 *
79 * @section urls
80 * URL strings in libavformat are made of a scheme/protocol, a ':', and a
81 * scheme specific string. URLs without a scheme and ':' used for local files
82 * are supported but deprecated. "file:" should be used for local files.
83 *
84 * It is important that the scheme string is not taken from untrusted
85 * sources without checks.
86 *
87 * Note that some schemes/protocols are quite powerful, allowing access to
88 * both local and remote files, parts of them, concatenations of them, local
89 * audio and video devices and so on.
90 *
91 * @{
92 *
93 * @defgroup lavf_decoding Demuxing
94 * @{
95 * Demuxers read a media file and split it into chunks of data (@em packets). A
96 * @ref AVPacket "packet" contains one or more encoded frames which belongs to a
97 * single elementary stream. In the lavf API this process is represented by the
98 * avformat_open_input() function for opening a file, av_read_frame() for
99 * reading a single packet and finally avformat_close_input(), which does the
100 * cleanup.
101 *
102 * @section lavf_decoding_open Opening a media file
103 * The minimum information required to open a file is its URL, which
104 * is passed to avformat_open_input(), as in the following code:
105 * @code
106 * const char *url = "file:in.mp3";
107 * AVFormatContext *s = NULL;
108 * int ret = avformat_open_input(&s, url, NULL, NULL);
109 * if (ret < 0)
110 * abort();
111 * @endcode
112 * The above code attempts to allocate an AVFormatContext, open the
113 * specified file (autodetecting the format) and read the header, exporting the
114 * information stored there into s. Some formats do not have a header or do not
115 * store enough information there, so it is recommended that you call the
116 * avformat_find_stream_info() function which tries to read and decode a few
117 * frames to find missing information.
118 *
119 * In some cases you might want to preallocate an AVFormatContext yourself with
120 * avformat_alloc_context() and do some tweaking on it before passing it to
121 * avformat_open_input(). One such case is when you want to use custom functions
122 * for reading input data instead of lavf internal I/O layer.
123 * To do that, create your own AVIOContext with avio_alloc_context(), passing
124 * your reading callbacks to it. Then set the @em pb field of your
125 * AVFormatContext to newly created AVIOContext.
126 *
127 * Since the format of the opened file is in general not known until after
128 * avformat_open_input() has returned, it is not possible to set demuxer private
129 * options on a preallocated context. Instead, the options should be passed to
130 * avformat_open_input() wrapped in an AVDictionary:
131 * @code
132 * AVDictionary *options = NULL;
133 * av_dict_set(&options, "video_size", "640x480", 0);
134 * av_dict_set(&options, "pixel_format", "rgb24", 0);
135 *
136 * if (avformat_open_input(&s, url, NULL, &options) < 0)
137 * abort();
138 * av_dict_free(&options);
139 * @endcode
140 * This code passes the private options 'video_size' and 'pixel_format' to the
141 * demuxer. They would be necessary for e.g. the rawvideo demuxer, since it
142 * cannot know how to interpret raw video data otherwise. If the format turns
143 * out to be something different than raw video, those options will not be
144 * recognized by the demuxer and therefore will not be applied. Such unrecognized
145 * options are then returned in the options dictionary (recognized options are
146 * consumed). The calling program can handle such unrecognized options as it
147 * wishes, e.g.
148 * @code
149 * AVDictionaryEntry *e;
150 * if (e = av_dict_get(options, "", NULL, AV_DICT_IGNORE_SUFFIX)) {
151 * fprintf(stderr, "Option %s not recognized by the demuxer.\n", e->key);
152 * abort();
153 * }
154 * @endcode
155 *
156 * After you have finished reading the file, you must close it with
157 * avformat_close_input(). It will free everything associated with the file.
158 *
159 * @section lavf_decoding_read Reading from an opened file
160 * Reading data from an opened AVFormatContext is done by repeatedly calling
161 * av_read_frame() on it. Each call, if successful, will return an AVPacket
162 * containing encoded data for one AVStream, identified by
163 * AVPacket.stream_index. This packet may be passed straight into the libavcodec
164 * decoding functions avcodec_send_packet() or avcodec_decode_subtitle2() if the
165 * caller wishes to decode the data.
166 *
167 * AVPacket.pts, AVPacket.dts and AVPacket.duration timing information will be
168 * set if known. They may also be unset (i.e. AV_NOPTS_VALUE for
169 * pts/dts, 0 for duration) if the stream does not provide them. The timing
170 * information will be in AVStream.time_base units, i.e. it has to be
171 * multiplied by the timebase to convert them to seconds.
172 *
173 * A packet returned by av_read_frame() is always reference-counted,
174 * i.e. AVPacket.buf is set and the user may keep it indefinitely.
175 * The packet must be freed with av_packet_unref() when it is no
176 * longer needed.
177 *
178 * @section lavf_decoding_seek Seeking
179 * @}
180 *
181 * @defgroup lavf_encoding Muxing
182 * @{
183 * Muxers take encoded data in the form of @ref AVPacket "AVPackets" and write
184 * it into files or other output bytestreams in the specified container format.
185 *
186 * The main API functions for muxing are avformat_write_header() for writing the
187 * file header, av_write_frame() / av_interleaved_write_frame() for writing the
188 * packets and av_write_trailer() for finalizing the file.
189 *
190 * At the beginning of the muxing process, the caller must first call
191 * avformat_alloc_context() to create a muxing context. The caller then sets up
192 * the muxer by filling the various fields in this context:
193 *
194 * - The @ref AVFormatContext.oformat "oformat" field must be set to select the
195 * muxer that will be used.
196 * - Unless the format is of the AVFMT_NOFILE type, the @ref AVFormatContext.pb
197 * "pb" field must be set to an opened IO context, either returned from
198 * avio_open2() or a custom one.
199 * - Unless the format is of the AVFMT_NOSTREAMS type, at least one stream must
200 * be created with the avformat_new_stream() function. The caller should fill
201 * the @ref AVStream.codecpar "stream codec parameters" information, such as the
202 * codec @ref AVCodecParameters.codec_type "type", @ref AVCodecParameters.codec_id
203 * "id" and other parameters (e.g. width / height, the pixel or sample format,
204 * etc.) as known. The @ref AVStream.time_base "stream timebase" should
205 * be set to the timebase that the caller desires to use for this stream (note
206 * that the timebase actually used by the muxer can be different, as will be
207 * described later).
208 * - It is advised to manually initialize only the relevant fields in
209 * AVCodecParameters, rather than using @ref avcodec_parameters_copy() during
210 * remuxing: there is no guarantee that the codec context values remain valid
211 * for both input and output format contexts.
212 * - The caller may fill in additional information, such as @ref
213 * AVFormatContext.metadata "global" or @ref AVStream.metadata "per-stream"
214 * metadata, @ref AVFormatContext.chapters "chapters", @ref
215 * AVFormatContext.programs "programs", etc. as described in the
216 * AVFormatContext documentation. Whether such information will actually be
217 * stored in the output depends on what the container format and the muxer
218 * support.
219 *
220 * When the muxing context is fully set up, the caller must call
221 * avformat_write_header() to initialize the muxer internals and write the file
222 * header. Whether anything actually is written to the IO context at this step
223 * depends on the muxer, but this function must always be called. Any muxer
224 * private options must be passed in the options parameter to this function.
225 *
226 * The data is then sent to the muxer by repeatedly calling av_write_frame() or
227 * av_interleaved_write_frame() (consult those functions' documentation for
228 * discussion on the difference between them; only one of them may be used with
229 * a single muxing context, they should not be mixed). Do note that the timing
230 * information on the packets sent to the muxer must be in the corresponding
231 * AVStream's timebase. That timebase is set by the muxer (in the
232 * avformat_write_header() step) and may be different from the timebase
233 * requested by the caller.
234 *
235 * Once all the data has been written, the caller must call av_write_trailer()
236 * to flush any buffered packets and finalize the output file, then close the IO
237 * context (if any) and finally free the muxing context with
238 * avformat_free_context().
239 * @}
240 *
241 * @defgroup lavf_io I/O Read/Write
242 * @{
243 * @section lavf_io_dirlist Directory listing
244 * The directory listing API makes it possible to list files on remote servers.
245 *
246 * Some of possible use cases:
247 * - an "open file" dialog to choose files from a remote location,
248 * - a recursive media finder providing a player with an ability to play all
249 * files from a given directory.
250 *
251 * @subsection lavf_io_dirlist_open Opening a directory
252 * At first, a directory needs to be opened by calling avio_open_dir()
253 * supplied with a URL and, optionally, ::AVDictionary containing
254 * protocol-specific parameters. The function returns zero or positive
255 * integer and allocates AVIODirContext on success.
256 *
257 * @code
258 * AVIODirContext *ctx = NULL;
259 * if (avio_open_dir(&ctx, "smb://example.com/some_dir", NULL) < 0) {
260 * fprintf(stderr, "Cannot open directory.\n");
261 * abort();
262 * }
263 * @endcode
264 *
265 * This code tries to open a sample directory using smb protocol without
266 * any additional parameters.
267 *
268 * @subsection lavf_io_dirlist_read Reading entries
269 * Each directory's entry (i.e. file, another directory, anything else
270 * within ::AVIODirEntryType) is represented by AVIODirEntry.
271 * Reading consecutive entries from an opened AVIODirContext is done by
272 * repeatedly calling avio_read_dir() on it. Each call returns zero or
273 * positive integer if successful. Reading can be stopped right after the
274 * NULL entry has been read -- it means there are no entries left to be
275 * read. The following code reads all entries from a directory associated
276 * with ctx and prints their names to standard output.
277 * @code
278 * AVIODirEntry *entry = NULL;
279 * for (;;) {
280 * if (avio_read_dir(ctx, &entry) < 0) {
281 * fprintf(stderr, "Cannot list directory.\n");
282 * abort();
283 * }
284 * if (!entry)
285 * break;
286 * printf("%s\n", entry->name);
287 * avio_free_directory_entry(&entry);
288 * }
289 * @endcode
290 * @}
291 *
292 * @defgroup lavf_codec Demuxers
293 * @{
294 * @defgroup lavf_codec_native Native Demuxers
295 * @{
296 * @}
297 * @defgroup lavf_codec_wrappers External library wrappers
298 * @{
299 * @}
300 * @}
301 * @defgroup lavf_protos I/O Protocols
302 * @{
303 * @}
304 * @defgroup lavf_internal Internal
305 * @{
306 * @}
307 * @}
308 */
309
310#include <stdio.h> /* FILE */
311
312#include "libavcodec/codec_par.h"
313#include "libavcodec/defs.h"
314#include "libavcodec/packet.h"
315
316#include "libavutil/dict.h"
317#include "libavutil/log.h"
318
319#include "avio.h"
321#ifndef HAVE_AV_CONFIG_H
322/* When included as part of the ffmpeg build, only include the major version
323 * to avoid unnecessary rebuilds. When included externally, keep including
324 * the full version information. */
325#include "libavformat/version.h"
326
327#include "libavutil/frame.h"
328#include "libavcodec/codec.h"
329#endif
330
331struct AVFormatContext;
332struct AVFrame;
333
334/**
335 * @defgroup metadata_api Public Metadata API
336 * @{
337 * @ingroup libavf
338 * The metadata API allows libavformat to export metadata tags to a client
339 * application when demuxing. Conversely it allows a client application to
340 * set metadata when muxing.
341 *
342 * Metadata is exported or set as pairs of key/value strings in the 'metadata'
343 * fields of the AVFormatContext, AVStream, AVChapter and AVProgram structs
344 * using the @ref lavu_dict "AVDictionary" API. Like all strings in FFmpeg,
345 * metadata is assumed to be UTF-8 encoded Unicode. Note that metadata
346 * exported by demuxers isn't checked to be valid UTF-8 in most cases.
347 *
348 * Important concepts to keep in mind:
349 * - Keys are unique; there can never be 2 tags with the same key. This is
350 * also meant semantically, i.e., a demuxer should not knowingly produce
351 * several keys that are literally different but semantically identical.
352 * E.g., key=Author5, key=Author6. In this example, all authors must be
353 * placed in the same tag.
354 * - Metadata is flat, not hierarchical; there are no subtags. If you
355 * want to store, e.g., the email address of the child of producer Alice
356 * and actor Bob, that could have key=alice_and_bobs_childs_email_address.
357 * - Several modifiers can be applied to the tag name. This is done by
358 * appending a dash character ('-') and the modifier name in the order
359 * they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng.
360 * - language -- a tag whose value is localized for a particular language
361 * is appended with the ISO 639-2/B 3-letter language code.
362 * For example: Author-ger=Michael, Author-eng=Mike
363 * The original/default language is in the unqualified "Author" tag.
364 * A demuxer should set a default if it sets any translated tag.
365 * - sorting -- a modified version of a tag that should be used for
366 * sorting will have '-sort' appended. E.g. artist="The Beatles",
367 * artist-sort="Beatles, The".
368 * - Some protocols and demuxers support metadata updates. After a successful
369 * call to av_read_frame(), AVFormatContext.event_flags or AVStream.event_flags
370 * will be updated to indicate if metadata changed. In order to detect metadata
371 * changes on a stream, you need to loop through all streams in the AVFormatContext
372 * and check their individual event_flags.
373 *
374 * - Demuxers attempt to export metadata in a generic format, however tags
375 * with no generic equivalents are left as they are stored in the container.
376 * Follows a list of generic tag names:
377 *
378 @verbatim
379 album -- name of the set this work belongs to
380 album_artist -- main creator of the set/album, if different from artist.
381 e.g. "Various Artists" for compilation albums.
382 artist -- main creator of the work
383 comment -- any additional description of the file.
384 composer -- who composed the work, if different from artist.
385 copyright -- name of copyright holder.
386 creation_time-- date when the file was created, preferably in ISO 8601.
387 date -- date when the work was created, preferably in ISO 8601.
388 disc -- number of a subset, e.g. disc in a multi-disc collection.
389 encoder -- name/settings of the software/hardware that produced the file.
390 encoded_by -- person/group who created the file.
391 filename -- original name of the file.
392 genre -- <self-evident>.
393 language -- main language in which the work is performed, preferably
394 in ISO 639-2 format. Multiple languages can be specified by
395 separating them with commas.
396 performer -- artist who performed the work, if different from artist.
397 E.g for "Also sprach Zarathustra", artist would be "Richard
398 Strauss" and performer "London Philharmonic Orchestra".
399 publisher -- name of the label/publisher.
400 service_name -- name of the service in broadcasting (channel name).
401 service_provider -- name of the service provider in broadcasting.
402 title -- name of the work.
403 track -- number of this work in the set, can be in form current/total.
404 variant_bitrate -- the total bitrate of the bitrate variant that the current stream is part of
405 @endverbatim
406 *
407 * Look in the examples section for an application example how to use the Metadata API.
408 *
409 * @}
410 */
411
412/* packet functions */
413
414
415/**
416 * Allocate and read the payload of a packet and initialize its
417 * fields with default values.
418 *
419 * @param s associated IO context
420 * @param pkt packet
421 * @param size desired payload size
422 * @return >0 (read size) if OK, AVERROR_xxx otherwise
423 */
425
426
427/**
428 * Read data and append it to the current content of the AVPacket.
429 * If pkt->size is 0 this is identical to av_get_packet.
430 * Note that this uses av_grow_packet and thus involves a realloc
431 * which is inefficient. Thus this function should only be used
432 * when there is no reasonable way to know (an upper bound of)
433 * the final size.
434 *
435 * @param s associated IO context
436 * @param pkt packet
437 * @param size amount of data to read
438 * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data
439 * will not be lost even if an error occurs.
440 */
442
443/*************************************************/
444/* input/output formats */
445
446struct AVCodecTag;
447
448/**
449 * This structure contains the data a format has to probe a file.
450 */
451typedef struct AVProbeData {
452 const char *filename;
453 unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
454 int buf_size; /**< Size of buf except extra allocated bytes */
455 const char *mime_type; /**< mime_type, when known. */
457
458#define AVPROBE_SCORE_RETRY (AVPROBE_SCORE_MAX/4)
459#define AVPROBE_SCORE_STREAM_RETRY (AVPROBE_SCORE_MAX/4-1)
460
461#define AVPROBE_SCORE_EXTENSION 50 ///< score for file extension
462#define AVPROBE_SCORE_MIME 75 ///< score for file mime type
463#define AVPROBE_SCORE_MAX 100 ///< maximum score
464
465#define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
466
467/// Demuxer will use avio_open, no opened file should be provided by the caller.
468#define AVFMT_NOFILE 0x0001
469#define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
470/**
471 * The muxer/demuxer is experimental and should be used with caution.
472 *
473 * - demuxers: will not be selected automatically by probing, must be specified
474 * explicitly.
475 */
476#define AVFMT_EXPERIMENTAL 0x0004
477#define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
478#define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
479#define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
480#define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
481#define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */
482#define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */
483#define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */
484#define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */
485#define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fall back on binary search via read_timestamp */
486#define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fall back on generic search */
487#define AVFMT_NO_BYTE_SEEK 0x8000 /**< Format does not allow seeking by bytes */
488#if FF_API_ALLOW_FLUSH
489#define AVFMT_ALLOW_FLUSH 0x10000 /**< @deprecated: Just send a NULL packet if you want to flush a muxer. */
490#endif
491#define AVFMT_TS_NONSTRICT 0x20000 /**< Format does not require strictly
492 increasing timestamps, but they must
493 still be monotonic */
494#define AVFMT_TS_NEGATIVE 0x40000 /**< Format allows muxing negative
495 timestamps. If not set the timestamp
496 will be shifted in av_write_frame and
497 av_interleaved_write_frame so they
498 start from 0.
499 The user or muxer can override this through
500 AVFormatContext.avoid_negative_ts
501 */
502
503#define AVFMT_SEEK_TO_PTS 0x4000000 /**< Seeking is based on PTS */
504
505/**
506 * @addtogroup lavf_encoding
507 * @{
508 */
509typedef struct AVOutputFormat {
510 const char *name;
511 /**
512 * Descriptive name for the format, meant to be more human-readable
513 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
514 * to define it.
515 */
516 const char *long_name;
517 const char *mime_type;
518 const char *extensions; /**< comma-separated filename extensions */
519 /* output support */
520 enum AVCodecID audio_codec; /**< default audio codec */
521 enum AVCodecID video_codec; /**< default video codec */
522 enum AVCodecID subtitle_codec; /**< default subtitle codec */
523 /**
524 * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER,
525 * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
526 * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS,
527 * AVFMT_TS_NONSTRICT, AVFMT_TS_NEGATIVE
528 */
529 int flags;
530
531 /**
532 * List of supported codec_id-codec_tag pairs, ordered by "better
533 * choice first". The arrays are all terminated by AV_CODEC_ID_NONE.
534 */
535 const struct AVCodecTag * const *codec_tag;
536
537
538 const AVClass *priv_class; ///< AVClass for the private context
540/**
541 * @}
542 */
543
544/**
545 * @addtogroup lavf_decoding
546 * @{
547 */
548typedef struct AVInputFormat {
549 /**
550 * A comma separated list of short names for the format. New names
551 * may be appended with a minor bump.
552 */
553 const char *name;
554
555 /**
556 * Descriptive name for the format, meant to be more human-readable
557 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
558 * to define it.
559 */
560 const char *long_name;
561
562 /**
563 * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
564 * AVFMT_NOTIMESTAMPS, AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
565 * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK, AVFMT_SEEK_TO_PTS.
566 */
567 int flags;
568
569 /**
570 * If extensions are defined, then no probe is done. You should
571 * usually not use extension format guessing because it is not
572 * reliable enough
573 */
574 const char *extensions;
575
576 const struct AVCodecTag * const *codec_tag;
577
578 const AVClass *priv_class; ///< AVClass for the private context
579
580 /**
581 * Comma-separated list of mime types.
582 * It is used check for matching mime types while probing.
583 * @see av_probe_input_format2
584 */
585 const char *mime_type;
587/**
588 * @}
589 */
590
593 AVSTREAM_PARSE_FULL, /**< full parsing and repack */
594 AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
595 AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
596 AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
597 AVSTREAM_PARSE_FULL_RAW, /**< full parsing and repack with timestamp and position generation by parser for raw
598 this assumes that each packet in the file contains no demuxer level headers and
599 just codec level data, otherwise position generation would fail */
600};
601
602typedef struct AVIndexEntry {
603 int64_t pos;
604 int64_t timestamp; /**<
605 * Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are available
606 * when seeking to this entry. That means preferable PTS on keyframe based formats.
607 * But demuxers can choose to store a different timestamp, if it is more convenient for the implementation or nothing better
608 * is known
609 */
610#define AVINDEX_KEYFRAME 0x0001
611#define AVINDEX_DISCARD_FRAME 0x0002 /**
612 * Flag is used to indicate which frame should be discarded after decoding.
613 */
614 int flags:2;
615 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).
616 int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
618
619/**
620 * The stream should be chosen by default among other streams of the same type,
621 * unless the user has explicitly specified otherwise.
622 */
623#define AV_DISPOSITION_DEFAULT (1 << 0)
624/**
625 * The stream is not in original language.
626 *
627 * @note AV_DISPOSITION_ORIGINAL is the inverse of this disposition. At most
628 * one of them should be set in properly tagged streams.
629 * @note This disposition may apply to any stream type, not just audio.
630 */
631#define AV_DISPOSITION_DUB (1 << 1)
632/**
633 * The stream is in original language.
634 *
635 * @see the notes for AV_DISPOSITION_DUB
636 */
637#define AV_DISPOSITION_ORIGINAL (1 << 2)
638/**
639 * The stream is a commentary track.
640 */
641#define AV_DISPOSITION_COMMENT (1 << 3)
642/**
643 * The stream contains song lyrics.
644 */
645#define AV_DISPOSITION_LYRICS (1 << 4)
646/**
647 * The stream contains karaoke audio.
648 */
649#define AV_DISPOSITION_KARAOKE (1 << 5)
650
651/**
652 * Track should be used during playback by default.
653 * Useful for subtitle track that should be displayed
654 * even when user did not explicitly ask for subtitles.
655 */
656#define AV_DISPOSITION_FORCED (1 << 6)
657/**
658 * The stream is intended for hearing impaired audiences.
659 */
660#define AV_DISPOSITION_HEARING_IMPAIRED (1 << 7)
661/**
662 * The stream is intended for visually impaired audiences.
663 */
664#define AV_DISPOSITION_VISUAL_IMPAIRED (1 << 8)
665/**
666 * The audio stream contains music and sound effects without voice.
667 */
668#define AV_DISPOSITION_CLEAN_EFFECTS (1 << 9)
669/**
670 * The stream is stored in the file as an attached picture/"cover art" (e.g.
671 * APIC frame in ID3v2). The first (usually only) packet associated with it
672 * will be returned among the first few packets read from the file unless
673 * seeking takes place. It can also be accessed at any time in
674 * AVStream.attached_pic.
675 */
676#define AV_DISPOSITION_ATTACHED_PIC (1 << 10)
677/**
678 * The stream is sparse, and contains thumbnail images, often corresponding
679 * to chapter markers. Only ever used with AV_DISPOSITION_ATTACHED_PIC.
680 */
681#define AV_DISPOSITION_TIMED_THUMBNAILS (1 << 11)
682
683/**
684 * The stream is intended to be mixed with a spatial audio track. For example,
685 * it could be used for narration or stereo music, and may remain unchanged by
686 * listener head rotation.
687 */
688#define AV_DISPOSITION_NON_DIEGETIC (1 << 12)
689
690/**
691 * The subtitle stream contains captions, providing a transcription and possibly
692 * a translation of audio. Typically intended for hearing-impaired audiences.
693 */
694#define AV_DISPOSITION_CAPTIONS (1 << 16)
695/**
696 * The subtitle stream contains a textual description of the video content.
697 * Typically intended for visually-impaired audiences or for the cases where the
698 * video cannot be seen.
699 */
700#define AV_DISPOSITION_DESCRIPTIONS (1 << 17)
701/**
702 * The subtitle stream contains time-aligned metadata that is not intended to be
703 * directly presented to the user.
704 */
705#define AV_DISPOSITION_METADATA (1 << 18)
706/**
707 * The stream is intended to be mixed with another stream before presentation.
708 * Used for example to signal the stream contains an image part of a HEIF grid,
709 * or for mix_type=0 in mpegts.
710 */
711#define AV_DISPOSITION_DEPENDENT (1 << 19)
712/**
713 * The video stream contains still images.
714 */
715#define AV_DISPOSITION_STILL_IMAGE (1 << 20)
716/**
717 * The video stream contains multiple layers, e.g. stereoscopic views (cf. H.264
718 * Annex G/H, or HEVC Annex F).
719 */
720#define AV_DISPOSITION_MULTILAYER (1 << 21)
721
722/**
723 * @return The AV_DISPOSITION_* flag corresponding to disp or a negative error
724 * code if disp does not correspond to a known stream disposition.
725 */
726int av_disposition_from_string(const char *disp);
727
728/**
729 * @param disposition a combination of AV_DISPOSITION_* values
730 * @return The string description corresponding to the lowest set bit in
731 * disposition. NULL when the lowest set bit does not correspond
732 * to a known disposition or when disposition is 0.
733 */
734const char *av_disposition_to_string(int disposition);
735
736/**
737 * Options for behavior on timestamp wrap detection.
738 */
739#define AV_PTS_WRAP_IGNORE 0 ///< ignore the wrap
740#define AV_PTS_WRAP_ADD_OFFSET 1 ///< add the format specific offset on wrap detection
741#define AV_PTS_WRAP_SUB_OFFSET -1 ///< subtract the format specific offset on wrap detection
742
743/**
744 * Stream structure.
745 * New fields can be added to the end with minor version bumps.
746 * Removal, reordering and changes to existing fields require a major
747 * version bump.
748 * sizeof(AVStream) must not be used outside libav*.
749 */
750typedef struct AVStream {
751 /**
752 * A class for @ref avoptions. Set on stream creation.
753 */
755
756 int index; /**< stream index in AVFormatContext */
757 /**
758 * Format-specific stream ID.
759 * decoding: set by libavformat
760 * encoding: set by the user, replaced by libavformat if left unset
761 */
762 int id;
763
764 /**
765 * Codec parameters associated with this stream. Allocated and freed by
766 * libavformat in avformat_new_stream() and avformat_free_context()
767 * respectively.
768 *
769 * - demuxing: filled by libavformat on stream creation or in
770 * avformat_find_stream_info()
771 * - muxing: filled by the caller before avformat_write_header()
772 */
774
775 void *priv_data;
776
777 /**
778 * This is the fundamental unit of time (in seconds) in terms
779 * of which frame timestamps are represented.
780 *
781 * decoding: set by libavformat
782 * encoding: May be set by the caller before avformat_write_header() to
783 * provide a hint to the muxer about the desired timebase. In
784 * avformat_write_header(), the muxer will overwrite this field
785 * with the timebase that will actually be used for the timestamps
786 * written into the file (which may or may not be related to the
787 * user-provided one, depending on the format).
788 */
790
791 /**
792 * Decoding: pts of the first frame of the stream in presentation order, in stream time base.
793 * Only set this if you are absolutely 100% sure that the value you set
794 * it to really is the pts of the first frame.
795 * This may be undefined (AV_NOPTS_VALUE).
796 * @note The ASF header does NOT contain a correct start_time the ASF
797 * demuxer must NOT set this.
798 */
799 int64_t start_time;
800
801 /**
802 * Decoding: duration of the stream, in stream time base.
803 * If a source file does not specify a duration, but does specify
804 * a bitrate, this value will be estimated from bitrate and file size.
805 *
806 * Encoding: May be set by the caller before avformat_write_header() to
807 * provide a hint to the muxer about the estimated duration.
808 */
809 int64_t duration;
810
811 int64_t nb_frames; ///< number of frames in this stream if known or 0
812
813 /**
814 * Stream disposition - a combination of AV_DISPOSITION_* flags.
815 * - demuxing: set by libavformat when creating the stream or in
816 * avformat_find_stream_info().
817 * - muxing: may be set by the caller before avformat_write_header().
818 */
820
821 enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
822
823 /**
824 * sample aspect ratio (0 if unknown)
825 * - encoding: Set by user.
826 * - decoding: Set by libavformat.
827 */
829
831
832 /**
833 * Average framerate
834 *
835 * - demuxing: May be set by libavformat when creating the stream or in
836 * avformat_find_stream_info().
837 * - muxing: May be set by the caller before avformat_write_header().
838 */
840
841 /**
842 * For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet
843 * will contain the attached picture.
844 *
845 * decoding: set by libavformat, must not be modified by the caller.
846 * encoding: unused
847 */
849
850#if FF_API_AVSTREAM_SIDE_DATA
851 /**
852 * An array of side data that applies to the whole stream (i.e. the
853 * container does not allow it to change between packets).
854 *
855 * There may be no overlap between the side data in this array and side data
856 * in the packets. I.e. a given side data is either exported by the muxer
857 * (demuxing) / set by the caller (muxing) in this array, then it never
858 * appears in the packets, or the side data is exported / sent through
859 * the packets (always in the first packet where the value becomes known or
860 * changes), then it does not appear in this array.
861 *
862 * - demuxing: Set by libavformat when the stream is created.
863 * - muxing: May be set by the caller before avformat_write_header().
864 *
865 * Freed by libavformat in avformat_free_context().
866 *
867 * @deprecated use AVStream's @ref AVCodecParameters.coded_side_data
868 * "codecpar side data".
869 */
871 AVPacketSideData *side_data;
872 /**
873 * The number of elements in the AVStream.side_data array.
874 *
875 * @deprecated use AVStream's @ref AVCodecParameters.nb_coded_side_data
876 * "codecpar side data".
877 */
879 int nb_side_data;
880#endif
881
882 /**
883 * Flags indicating events happening on the stream, a combination of
884 * AVSTREAM_EVENT_FLAG_*.
885 *
886 * - demuxing: may be set by the demuxer in avformat_open_input(),
887 * avformat_find_stream_info() and av_read_frame(). Flags must be cleared
888 * by the user once the event has been handled.
889 * - muxing: may be set by the user after avformat_write_header(). to
890 * indicate a user-triggered event. The muxer will clear the flags for
891 * events it has handled in av_[interleaved]_write_frame().
892 */
893 int event_flags;
894/**
895 * - demuxing: the demuxer read new metadata from the file and updated
896 * AVStream.metadata accordingly
897 * - muxing: the user updated AVStream.metadata and wishes the muxer to write
898 * it into the file
899 */
900#define AVSTREAM_EVENT_FLAG_METADATA_UPDATED 0x0001
901/**
902 * - demuxing: new packets for this stream were read from the file. This
903 * event is informational only and does not guarantee that new packets
904 * for this stream will necessarily be returned from av_read_frame().
905 */
906#define AVSTREAM_EVENT_FLAG_NEW_PACKETS (1 << 1)
907
908 /**
909 * Real base framerate of the stream.
910 * This is the lowest framerate with which all timestamps can be
911 * represented accurately (it is the least common multiple of all
912 * framerates in the stream). Note, this value is just a guess!
913 * For example, if the time base is 1/90000 and all frames have either
914 * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
915 */
917
918 /**
919 * Number of bits in timestamps. Used for wrapping control.
920 *
921 * - demuxing: set by libavformat
922 * - muxing: set by libavformat
924 */
925 int pts_wrap_bits;
926} AVStream;
927
928/**
929 * AVStreamGroupTileGrid holds information on how to combine several
930 * independent images on a single canvas for presentation.
931 *
932 * The output should be a @ref AVStreamGroupTileGrid.background "background"
933 * colored @ref AVStreamGroupTileGrid.coded_width "coded_width" x
934 * @ref AVStreamGroupTileGrid.coded_height "coded_height" canvas where a
935 * @ref AVStreamGroupTileGrid.nb_tiles "nb_tiles" amount of tiles are placed in
936 * the order they appear in the @ref AVStreamGroupTileGrid.offsets "offsets"
937 * array, at the exact offset described for them. In particular, if two or more
938 * tiles overlap, the image with higher index in the
939 * @ref AVStreamGroupTileGrid.offsets "offsets" array takes priority.
940 * Note that a single image may be used multiple times, i.e. multiple entries
941 * in @ref AVStreamGroupTileGrid.offsets "offsets" may have the same value of
942 * idx.
943 *
944 * The following is an example of a simple grid with 3 rows and 4 columns:
945 *
946 * +---+---+---+---+
947 * | 0 | 1 | 2 | 3 |
948 * +---+---+---+---+
949 * | 4 | 5 | 6 | 7 |
950 * +---+---+---+---+
951 * | 8 | 9 |10 |11 |
952 * +---+---+---+---+
953 *
954 * Assuming all tiles have a dimension of 512x512, the
955 * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
956 * the first @ref AVStreamGroup.streams "stream" in the group is "0,0", the
957 * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
958 * the second @ref AVStreamGroup.streams "stream" in the group is "512,0", the
959 * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
960 * the fifth @ref AVStreamGroup.streams "stream" in the group is "0,512", the
961 * @ref AVStreamGroupTileGrid.offsets "offset", of the topleft pixel of
962 * the sixth @ref AVStreamGroup.streams "stream" in the group is "512,512",
963 * etc.
964 *
965 * The following is an example of a canvas with overlaping tiles:
966 *
967 * +-----------+
968 * | %%%%% |
969 * |***%%3%%@@@|
970 * |**0%%%%%2@@|
971 * |***##1@@@@@|
972 * | ##### |
973 * +-----------+
974 *
975 * Assuming a canvas with size 1024x1024 and all tiles with a dimension of
976 * 512x512, a possible @ref AVStreamGroupTileGrid.offsets "offset" for the
977 * topleft pixel of the first @ref AVStreamGroup.streams "stream" in the group
978 * would be 0x256, the @ref AVStreamGroupTileGrid.offsets "offset" for the
979 * topleft pixel of the second @ref AVStreamGroup.streams "stream" in the group
980 * would be 256x512, the @ref AVStreamGroupTileGrid.offsets "offset" for the
981 * topleft pixel of the third @ref AVStreamGroup.streams "stream" in the group
982 * would be 512x256, and the @ref AVStreamGroupTileGrid.offsets "offset" for
983 * the topleft pixel of the fourth @ref AVStreamGroup.streams "stream" in the
984 * group would be 256x0.
985 *
986 * sizeof(AVStreamGroupTileGrid) is not a part of the ABI and may only be
987 * allocated by avformat_stream_group_create().
988 */
989typedef struct AVStreamGroupTileGrid {
990 const AVClass *av_class;
991
992 /**
993 * Amount of tiles in the grid.
994 *
995 * Must be > 0.
996 */
997 unsigned int nb_tiles;
998
999 /**
1000 * Width of the canvas.
1001 *
1002 * Must be > 0.
1003 */
1004 int coded_width;
1005 /**
1006 * Width of the canvas.
1007 *
1008 * Must be > 0.
1009 */
1010 int coded_height;
1011
1012 /**
1013 * An @ref nb_tiles sized array of offsets in pixels from the topleft edge
1014 * of the canvas, indicating where each stream should be placed.
1015 * It must be allocated with the av_malloc() family of functions.
1016 *
1017 * - demuxing: set by libavformat, must not be modified by the caller.
1018 * - muxing: set by the caller before avformat_write_header().
1019 *
1020 * Freed by libavformat in avformat_free_context().
1021 */
1022 struct {
1023 /**
1024 * Index of the stream in the group this tile references.
1025 *
1026 * Must be < @ref AVStreamGroup.nb_streams "nb_streams".
1027 */
1028 unsigned int idx;
1029 /**
1030 * Offset in pixels from the left edge of the canvas where the tile
1031 * should be placed.
1032 */
1033 int horizontal;
1034 /**
1035 * Offset in pixels from the top edge of the canvas where the tile
1036 * should be placed.
1038 int vertical;
1039 } *offsets;
1040
1041 /**
1042 * The pixel value per channel in RGBA format used if no pixel of any tile
1043 * is located at a particular pixel location.
1044 *
1045 * @see av_image_fill_color().
1046 * @see av_parse_color().
1047 */
1048 uint8_t background[4];
1049
1050 /**
1051 * Offset in pixels from the left edge of the canvas where the actual image
1052 * meant for presentation starts.
1053 *
1054 * This field must be >= 0 and < @ref coded_width.
1055 */
1057 /**
1058 * Offset in pixels from the top edge of the canvas where the actual image
1059 * meant for presentation starts.
1060 *
1061 * This field must be >= 0 and < @ref coded_height.
1062 */
1063 int vertical_offset;
1064
1065 /**
1066 * Width of the final image for presentation.
1067 *
1068 * Must be > 0 and <= (@ref coded_width - @ref horizontal_offset).
1069 * When it's not equal to (@ref coded_width - @ref horizontal_offset), the
1070 * result of (@ref coded_width - width - @ref horizontal_offset) is the
1071 * amount amount of pixels to be cropped from the right edge of the
1072 * final image before presentation.
1073 */
1074 int width;
1075 /**
1076 * Height of the final image for presentation.
1077 *
1078 * Must be > 0 and <= (@ref coded_height - @ref vertical_offset).
1079 * When it's not equal to (@ref coded_height - @ref vertical_offset), the
1080 * result of (@ref coded_height - height - @ref vertical_offset) is the
1081 * amount amount of pixels to be cropped from the bottom edge of the
1082 * final image before presentation.
1083 */
1084 int height;
1086
1087/**
1088 * AVStreamGroupLCEVC is meant to define the relation between video streams
1089 * and a data stream containing LCEVC enhancement layer NALUs.
1090 *
1091 * No more than one stream of @ref AVCodecParameters.codec_type "codec_type"
1092 * AVMEDIA_TYPE_DATA shall be present, and it must be of
1093 * @ref AVCodecParameters.codec_id "codec_id" AV_CODEC_ID_LCEVC.
1095typedef struct AVStreamGroupLCEVC {
1096 const AVClass *av_class;
1097
1098 /**
1099 * Index of the LCEVC data stream in AVStreamGroup.
1100 */
1101 unsigned int lcevc_index;
1102 /**
1103 * Width of the final stream for presentation.
1104 */
1105 int width;
1106 /**
1107 * Height of the final image for presentation.
1108 */
1109 int height;
1118};
1119
1120struct AVIAMFAudioElement;
1122
1123typedef struct AVStreamGroup {
1124 /**
1125 * A class for @ref avoptions. Set by avformat_stream_group_create().
1126 */
1128
1129 void *priv_data;
1130
1131 /**
1132 * Group index in AVFormatContext.
1133 */
1134 unsigned int index;
1135
1136 /**
1137 * Group type-specific group ID.
1138 *
1139 * decoding: set by libavformat
1140 * encoding: may set by the user
1141 */
1142 int64_t id;
1143
1144 /**
1145 * Group type
1146 *
1147 * decoding: set by libavformat on group creation
1148 * encoding: set by avformat_stream_group_create()
1149 */
1151
1152 /**
1153 * Group type-specific parameters
1155 union {
1159 struct AVStreamGroupLCEVC *lcevc;
1160 } params;
1161
1162 /**
1163 * Metadata that applies to the whole group.
1164 *
1165 * - demuxing: set by libavformat on group creation
1166 * - muxing: may be set by the caller before avformat_write_header()
1167 *
1168 * Freed by libavformat in avformat_free_context().
1169 */
1171
1172 /**
1173 * Number of elements in AVStreamGroup.streams.
1174 *
1175 * Set by avformat_stream_group_add_stream() must not be modified by any other code.
1176 */
1177 unsigned int nb_streams;
1178
1179 /**
1180 * A list of streams in the group. New entries are created with
1181 * avformat_stream_group_add_stream().
1182 *
1183 * - demuxing: entries are created by libavformat on group creation.
1184 * If AVFMTCTX_NOHEADER is set in ctx_flags, then new entries may also
1185 * appear in av_read_frame().
1186 * - muxing: entries are created by the user before avformat_write_header().
1187 *
1188 * Freed by libavformat in avformat_free_context().
1189 */
1190 AVStream **streams;
1191
1192 /**
1193 * Stream group disposition - a combination of AV_DISPOSITION_* flags.
1194 * This field currently applies to all defined AVStreamGroupParamsType.
1195 *
1196 * - demuxing: set by libavformat when creating the group or in
1197 * avformat_find_stream_info().
1198 * - muxing: may be set by the caller before avformat_write_header().
1199 */
1200 int disposition;
1202
1204
1205#define AV_PROGRAM_RUNNING 1
1206
1207/**
1208 * New fields can be added to the end with minor version bumps.
1209 * Removal, reordering and changes to existing fields require a major
1210 * version bump.
1211 * sizeof(AVProgram) must not be used outside libav*.
1213typedef struct AVProgram {
1214 int id;
1216 enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
1217 unsigned int *stream_index;
1218 unsigned int nb_stream_indexes;
1223 int pcr_pid;
1224 int pmt_version;
1225
1226 /*****************************************************************
1227 * All fields below this line are not part of the public API. They
1228 * may not be used outside of libavformat and can be changed and
1229 * removed at will.
1230 * New public fields should be added right above.
1231 *****************************************************************
1233 int64_t start_time;
1234 int64_t end_time;
1236 int64_t pts_wrap_reference; ///< reference dts for wrap detection
1237 int pts_wrap_behavior; ///< behavior on wrap detection
1238} AVProgram;
1240#define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
1241 (streams are added dynamically) */
1242#define AVFMTCTX_UNSEEKABLE 0x0002 /**< signal that the stream is definitely
1243 not seekable, and attempts to call the
1244 seek function will fail. For some
1245 network protocols (e.g. HLS), this can
1246 change dynamically at runtime. */
1248typedef struct AVChapter {
1249 int64_t id; ///< unique ID to identify the chapter
1250 AVRational time_base; ///< time base in which the start/end timestamps are specified
1251 int64_t start, end; ///< chapter start/end time in time_base units
1253} AVChapter;
1254
1255
1256/**
1257 * Callback used by devices to communicate with application.
1258 */
1259typedef int (*av_format_control_message)(struct AVFormatContext *s, int type,
1260 void *data, size_t data_size);
1261
1262typedef int (*AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags,
1263 const AVIOInterruptCB *int_cb, AVDictionary **options);
1264
1265/**
1266 * The duration of a video can be estimated through various ways, and this enum can be used
1267 * to know how the duration was estimated.
1270 AVFMT_DURATION_FROM_PTS, ///< Duration accurately estimated from PTSes
1271 AVFMT_DURATION_FROM_STREAM, ///< Duration estimated from a stream with a known duration
1272 AVFMT_DURATION_FROM_BITRATE ///< Duration estimated from bitrate (less accurate)
1273};
1274
1275/**
1276 * Format I/O context.
1277 * New fields can be added to the end with minor version bumps.
1278 * Removal, reordering and changes to existing fields require a major
1279 * version bump.
1280 * sizeof(AVFormatContext) must not be used outside libav*, use
1281 * avformat_alloc_context() to create an AVFormatContext.
1282 *
1283 * Fields can be accessed through AVOptions (av_opt*),
1284 * the name string used matches the associated command line parameter name and
1285 * can be found in libavformat/options_table.h.
1286 * The AVOption/command line parameter names differ in some cases from the C
1287 * structure field names for historic reasons or brevity.
1288 */
1289typedef struct AVFormatContext {
1290 /**
1291 * A class for logging and @ref avoptions. Set by avformat_alloc_context().
1292 * Exports (de)muxer private options if they exist.
1293 */
1294 const AVClass *av_class;
1295
1296 /**
1297 * The input container format.
1298 *
1299 * Demuxing only, set by avformat_open_input().
1300 */
1301 const struct AVInputFormat *iformat;
1302
1303 /**
1304 * The output container format.
1305 *
1306 * Muxing only, must be set by the caller before avformat_write_header().
1307 */
1308 const struct AVOutputFormat *oformat;
1309
1310 /**
1311 * Format private data. This is an AVOptions-enabled struct
1312 * if and only if iformat/oformat.priv_class is not NULL.
1313 *
1314 * - muxing: set by avformat_write_header()
1315 * - demuxing: set by avformat_open_input()
1316 */
1317 void *priv_data;
1318
1319 /**
1320 * I/O context.
1321 *
1322 * - demuxing: either set by the user before avformat_open_input() (then
1323 * the user must close it manually) or set by avformat_open_input().
1324 * - muxing: set by the user before avformat_write_header(). The caller must
1325 * take care of closing / freeing the IO context.
1326 *
1327 * Do NOT set this field if AVFMT_NOFILE flag is set in
1328 * iformat/oformat.flags. In such a case, the (de)muxer will handle
1329 * I/O in some other way and this field will be NULL.
1330 */
1331 AVIOContext *pb;
1332
1333 /* stream info */
1334 /**
1335 * Flags signalling stream properties. A combination of AVFMTCTX_*.
1336 * Set by libavformat.
1337 */
1338 int ctx_flags;
1339
1340 /**
1341 * Number of elements in AVFormatContext.streams.
1342 *
1343 * Set by avformat_new_stream(), must not be modified by any other code.
1344 */
1345 unsigned int nb_streams;
1346 /**
1347 * A list of all streams in the file. New streams are created with
1348 * avformat_new_stream().
1349 *
1350 * - demuxing: streams are created by libavformat in avformat_open_input().
1351 * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
1352 * appear in av_read_frame().
1353 * - muxing: streams are created by the user before avformat_write_header().
1354 *
1355 * Freed by libavformat in avformat_free_context().
1356 */
1357 AVStream **streams;
1358
1359 /**
1360 * Number of elements in AVFormatContext.stream_groups.
1361 *
1362 * Set by avformat_stream_group_create(), must not be modified by any other code.
1363 */
1364 unsigned int nb_stream_groups;
1365 /**
1366 * A list of all stream groups in the file. New groups are created with
1367 * avformat_stream_group_create(), and filled with avformat_stream_group_add_stream().
1368 *
1369 * - demuxing: groups may be created by libavformat in avformat_open_input().
1370 * If AVFMTCTX_NOHEADER is set in ctx_flags, then new groups may also
1371 * appear in av_read_frame().
1372 * - muxing: groups may be created by the user before avformat_write_header().
1373 *
1374 * Freed by libavformat in avformat_free_context().
1375 */
1377
1378 /**
1379 * Number of chapters in AVChapter array.
1380 * When muxing, chapters are normally written in the file header,
1381 * so nb_chapters should normally be initialized before write_header
1382 * is called. Some muxers (e.g. mov and mkv) can also write chapters
1383 * in the trailer. To write chapters in the trailer, nb_chapters
1384 * must be zero when write_header is called and non-zero when
1385 * write_trailer is called.
1386 * - muxing: set by user
1387 * - demuxing: set by libavformat
1389 unsigned int nb_chapters;
1391
1392 /**
1393 * input or output URL. Unlike the old filename field, this field has no
1394 * length restriction.
1395 *
1396 * - demuxing: set by avformat_open_input(), initialized to an empty
1397 * string if url parameter was NULL in avformat_open_input().
1398 * - muxing: may be set by the caller before calling avformat_write_header()
1399 * (or avformat_init_output() if that is called first) to a string
1400 * which is freeable by av_free(). Set to an empty string if it
1401 * was NULL in avformat_init_output().
1402 *
1403 * Freed by libavformat in avformat_free_context().
1404 */
1405 char *url;
1406
1407 /**
1408 * Position of the first frame of the component, in
1409 * AV_TIME_BASE fractional seconds. NEVER set this value directly:
1410 * It is deduced from the AVStream values.
1411 *
1412 * Demuxing only, set by libavformat.
1413 */
1414 int64_t start_time;
1415
1416 /**
1417 * Duration of the stream, in AV_TIME_BASE fractional
1418 * seconds. Only set this value if you know none of the individual stream
1419 * durations and also do not set any of them. This is deduced from the
1420 * AVStream values if not set.
1421 *
1422 * Demuxing only, set by libavformat.
1423 */
1424 int64_t duration;
1425
1426 /**
1427 * Total stream bitrate in bit/s, 0 if not
1428 * available. Never set it directly if the file_size and the
1429 * duration are known as FFmpeg can compute it automatically.
1430 */
1431 int64_t bit_rate;
1433 unsigned int packet_size;
1434 int max_delay;
1435
1436 /**
1437 * Flags modifying the (de)muxer behaviour. A combination of AVFMT_FLAG_*.
1438 * Set by the user before avformat_open_input() / avformat_write_header().
1441#define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
1442#define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
1443#define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
1444#define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
1445#define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
1446#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
1447#define AVFMT_FLAG_NOBUFFER 0x0040 ///< Do not buffer frames when possible
1448#define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
1449#define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted
1450#define AVFMT_FLAG_FLUSH_PACKETS 0x0200 ///< Flush the AVIOContext every packet.
1451/**
1452 * When muxing, try to avoid writing any random/volatile data to the output.
1453 * This includes any random IDs, real-time timestamps/dates, muxer version, etc.
1454 *
1455 * This flag is mainly intended for testing.
1457#define AVFMT_FLAG_BITEXACT 0x0400
1458#define AVFMT_FLAG_SORT_DTS 0x10000 ///< try to interleave outputted packets by dts (using this flag can slow demuxing down)
1459#define AVFMT_FLAG_FAST_SEEK 0x80000 ///< Enable fast, but inaccurate seeks for some formats
1460#if FF_API_LAVF_SHORTEST
1461#define AVFMT_FLAG_SHORTEST 0x100000 ///< Stop muxing when the shortest stream stops.
1462#endif
1463#define AVFMT_FLAG_AUTO_BSF 0x200000 ///< Add bitstream filters as requested by the muxer
1464
1465 /**
1466 * Maximum number of bytes read from input in order to determine stream
1467 * properties. Used when reading the global header and in
1468 * avformat_find_stream_info().
1469 *
1470 * Demuxing only, set by the caller before avformat_open_input().
1471 *
1472 * @note this is \e not used for determining the \ref AVInputFormat
1473 * "input format"
1474 * @see format_probesize
1475 */
1476 int64_t probesize;
1477
1478 /**
1479 * Maximum duration (in AV_TIME_BASE units) of the data read
1480 * from input in avformat_find_stream_info().
1481 * Demuxing only, set by the caller before avformat_find_stream_info().
1482 * Can be set to 0 to let avformat choose using a heuristic.
1483 */
1486 const uint8_t *key;
1489 unsigned int nb_programs;
1491
1492 /**
1493 * Forced video codec_id.
1494 * Demuxing: Set by user.
1495 */
1497
1498 /**
1499 * Forced audio codec_id.
1500 * Demuxing: Set by user.
1501 */
1503
1504 /**
1505 * Forced subtitle codec_id.
1506 * Demuxing: Set by user.
1507 */
1509
1510 /**
1511 * Forced Data codec_id.
1512 * Demuxing: Set by user.
1513 */
1515
1516 /**
1517 * Metadata that applies to the whole file.
1518 *
1519 * - demuxing: set by libavformat in avformat_open_input()
1520 * - muxing: may be set by the caller before avformat_write_header()
1521 *
1522 * Freed by libavformat in avformat_free_context().
1523 */
1525
1526 /**
1527 * Start time of the stream in real world time, in microseconds
1528 * since the Unix epoch (00:00 1st January 1970). That is, pts=0 in the
1529 * stream was captured at this real world time.
1530 * - muxing: Set by the caller before avformat_write_header(). If set to
1531 * either 0 or AV_NOPTS_VALUE, then the current wall-time will
1532 * be used.
1533 * - demuxing: Set by libavformat. AV_NOPTS_VALUE if unknown. Note that
1534 * the value may become known after some number of frames
1535 * have been received.
1536 */
1537 int64_t start_time_realtime;
1538
1539 /**
1540 * The number of frames used for determining the framerate in
1541 * avformat_find_stream_info().
1542 * Demuxing only, set by the caller before avformat_find_stream_info().
1543 */
1544 int fps_probe_size;
1545
1546 /**
1547 * Error recognition; higher values will detect more errors but may
1548 * misdetect some more or less valid parts as errors.
1549 * Demuxing only, set by the caller before avformat_open_input().
1550 */
1552
1553 /**
1554 * Custom interrupt callbacks for the I/O layer.
1555 *
1556 * demuxing: set by the user before avformat_open_input().
1557 * muxing: set by the user before avformat_write_header()
1558 * (mainly useful for AVFMT_NOFILE formats). The callback
1559 * should also be passed to avio_open2() if it's used to
1560 * open the file.
1561 */
1563
1564 /**
1565 * Flags to enable debugging.
1567 int debug;
1568#define FF_FDEBUG_TS 0x0001
1569
1570 /**
1571 * The maximum number of streams.
1572 * - encoding: unused
1573 * - decoding: set by user
1574 */
1575 int max_streams;
1576
1577 /**
1578 * Maximum amount of memory in bytes to use for the index of each stream.
1579 * If the index exceeds this size, entries will be discarded as
1580 * needed to maintain a smaller size. This can lead to slower or less
1581 * accurate seeking (depends on demuxer).
1582 * Demuxers for which a full in-memory index is mandatory will ignore
1583 * this.
1584 * - muxing: unused
1585 * - demuxing: set by user
1586 */
1587 unsigned int max_index_size;
1588
1589 /**
1590 * Maximum amount of memory in bytes to use for buffering frames
1591 * obtained from realtime capture devices.
1592 */
1593 unsigned int max_picture_buffer;
1594
1595 /**
1596 * Maximum buffering duration for interleaving.
1597 *
1598 * To ensure all the streams are interleaved correctly,
1599 * av_interleaved_write_frame() will wait until it has at least one packet
1600 * for each stream before actually writing any packets to the output file.
1601 * When some streams are "sparse" (i.e. there are large gaps between
1602 * successive packets), this can result in excessive buffering.
1603 *
1604 * This field specifies the maximum difference between the timestamps of the
1605 * first and the last packet in the muxing queue, above which libavformat
1606 * will output a packet regardless of whether it has queued a packet for all
1607 * the streams.
1608 *
1609 * Muxing only, set by the caller before avformat_write_header().
1610 */
1611 int64_t max_interleave_delta;
1612
1613 /**
1614 * Maximum number of packets to read while waiting for the first timestamp.
1615 * Decoding only.
1616 */
1617 int max_ts_probe;
1618
1619 /**
1620 * Max chunk time in microseconds.
1621 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1622 * - encoding: Set by user
1623 * - decoding: unused
1624 */
1626
1627 /**
1628 * Max chunk size in bytes
1629 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1630 * - encoding: Set by user
1631 * - decoding: unused
1632 */
1633 int max_chunk_size;
1634
1635 /**
1636 * Maximum number of packets that can be probed
1637 * - encoding: unused
1638 * - decoding: set by user
1639 */
1641
1642 /**
1643 * Allow non-standard and experimental extension
1644 * @see AVCodecContext.strict_std_compliance
1645 */
1647
1648 /**
1649 * Flags indicating events happening on the file, a combination of
1650 * AVFMT_EVENT_FLAG_*.
1651 *
1652 * - demuxing: may be set by the demuxer in avformat_open_input(),
1653 * avformat_find_stream_info() and av_read_frame(). Flags must be cleared
1654 * by the user once the event has been handled.
1655 * - muxing: may be set by the user after avformat_write_header() to
1656 * indicate a user-triggered event. The muxer will clear the flags for
1657 * events it has handled in av_[interleaved]_write_frame().
1658 */
1659 int event_flags;
1660/**
1661 * - demuxing: the demuxer read new metadata from the file and updated
1662 * AVFormatContext.metadata accordingly
1663 * - muxing: the user updated AVFormatContext.metadata and wishes the muxer to
1664 * write it into the file
1665 */
1666#define AVFMT_EVENT_FLAG_METADATA_UPDATED 0x0001
1667
1668
1669 /**
1670 * Avoid negative timestamps during muxing.
1671 * Any value of the AVFMT_AVOID_NEG_TS_* constants.
1672 * Note, this works better when using av_interleaved_write_frame().
1673 * - muxing: Set by user
1674 * - demuxing: unused
1677#define AVFMT_AVOID_NEG_TS_AUTO -1 ///< Enabled when required by target format
1678#define AVFMT_AVOID_NEG_TS_DISABLED 0 ///< Do not shift timestamps even when they are negative.
1679#define AVFMT_AVOID_NEG_TS_MAKE_NON_NEGATIVE 1 ///< Shift timestamps so they are non negative
1680#define AVFMT_AVOID_NEG_TS_MAKE_ZERO 2 ///< Shift timestamps so that they start at 0
1681
1682 /**
1683 * Audio preload in microseconds.
1684 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1685 * - encoding: Set by user
1686 * - decoding: unused
1687 */
1688 int audio_preload;
1689
1690 /**
1691 * forces the use of wallclock timestamps as pts/dts of packets
1692 * This has undefined results in the presence of B frames.
1693 * - encoding: unused
1694 * - decoding: Set by user
1695 */
1697
1698 /**
1699 * Skip duration calcuation in estimate_timings_from_pts.
1700 * - encoding: unused
1701 * - decoding: set by user
1702 *
1703 * @see duration_probesize
1704 */
1706
1707 /**
1708 * avio flags, used to force AVIO_FLAG_DIRECT.
1709 * - encoding: unused
1710 * - decoding: Set by user
1711 */
1712 int avio_flags;
1713
1714 /**
1715 * The duration field can be estimated through various ways, and this field can be used
1716 * to know how the duration was estimated.
1717 * - encoding: unused
1718 * - decoding: Read by user
1719 */
1721
1722 /**
1723 * Skip initial bytes when opening stream
1724 * - encoding: unused
1725 * - decoding: Set by user
1726 */
1727 int64_t skip_initial_bytes;
1728
1729 /**
1730 * Correct single timestamp overflows
1731 * - encoding: unused
1732 * - decoding: Set by user
1733 */
1734 unsigned int correct_ts_overflow;
1735
1736 /**
1737 * Force seeking to any (also non key) frames.
1738 * - encoding: unused
1739 * - decoding: Set by user
1740 */
1741 int seek2any;
1742
1743 /**
1744 * Flush the I/O context after each packet.
1745 * - encoding: Set by user
1746 * - decoding: unused
1747 */
1748 int flush_packets;
1749
1750 /**
1751 * format probing score.
1752 * The maximal score is AVPROBE_SCORE_MAX, its set when the demuxer probes
1753 * the format.
1754 * - encoding: unused
1755 * - decoding: set by avformat, read by user
1756 */
1757 int probe_score;
1758
1759 /**
1760 * Maximum number of bytes read from input in order to identify the
1761 * \ref AVInputFormat "input format". Only used when the format is not set
1762 * explicitly by the caller.
1763 *
1764 * Demuxing only, set by the caller before avformat_open_input().
1765 *
1766 * @see probesize
1767 */
1768 int format_probesize;
1769
1770 /**
1771 * ',' separated list of allowed decoders.
1772 * If NULL then all are allowed
1773 * - encoding: unused
1774 * - decoding: set by user
1775 */
1776 char *codec_whitelist;
1777
1778 /**
1779 * ',' separated list of allowed demuxers.
1780 * If NULL then all are allowed
1781 * - encoding: unused
1782 * - decoding: set by user
1783 */
1784 char *format_whitelist;
1785
1786 /**
1787 * ',' separated list of allowed protocols.
1788 * - encoding: unused
1789 * - decoding: set by user
1790 */
1791 char *protocol_whitelist;
1792
1793 /**
1794 * ',' separated list of disallowed protocols.
1795 * - encoding: unused
1796 * - decoding: set by user
1797 */
1798 char *protocol_blacklist;
1799
1800 /**
1801 * IO repositioned flag.
1802 * This is set by avformat when the underlaying IO context read pointer
1803 * is repositioned, for example when doing byte based seeking.
1804 * Demuxers can use the flag to detect such changes.
1805 */
1806 int io_repositioned;
1807
1808 /**
1809 * Forced video codec.
1810 * This allows forcing a specific decoder, even when there are multiple with
1811 * the same codec_id.
1812 * Demuxing: Set by user
1813 */
1814 const struct AVCodec *video_codec;
1815
1816 /**
1817 * Forced audio codec.
1818 * This allows forcing a specific decoder, even when there are multiple with
1819 * the same codec_id.
1820 * Demuxing: Set by user
1821 */
1822 const struct AVCodec *audio_codec;
1823
1824 /**
1825 * Forced subtitle codec.
1826 * This allows forcing a specific decoder, even when there are multiple with
1827 * the same codec_id.
1828 * Demuxing: Set by user
1829 */
1830 const struct AVCodec *subtitle_codec;
1831
1832 /**
1833 * Forced data codec.
1834 * This allows forcing a specific decoder, even when there are multiple with
1835 * the same codec_id.
1836 * Demuxing: Set by user
1837 */
1838 const struct AVCodec *data_codec;
1839
1840 /**
1841 * Number of bytes to be written as padding in a metadata header.
1842 * Demuxing: Unused.
1843 * Muxing: Set by user.
1844 */
1846
1847 /**
1848 * User data.
1849 * This is a place for some private data of the user.
1850 */
1851 void *opaque;
1852
1853 /**
1854 * Callback used by devices to communicate with application.
1855 */
1857
1858 /**
1859 * Output timestamp offset, in microseconds.
1860 * Muxing: set by user
1861 */
1862 int64_t output_ts_offset;
1863
1864 /**
1865 * dump format separator.
1866 * can be ", " or "\n " or anything else
1867 * - muxing: Set by user.
1868 * - demuxing: Set by user.
1869 */
1870 uint8_t *dump_separator;
1871
1872 /**
1873 * A callback for opening new IO streams.
1874 *
1875 * Whenever a muxer or a demuxer needs to open an IO stream (typically from
1876 * avformat_open_input() for demuxers, but for certain formats can happen at
1877 * other times as well), it will call this callback to obtain an IO context.
1878 *
1879 * @param s the format context
1880 * @param pb on success, the newly opened IO context should be returned here
1881 * @param url the url to open
1882 * @param flags a combination of AVIO_FLAG_*
1883 * @param options a dictionary of additional options, with the same
1884 * semantics as in avio_open2()
1885 * @return 0 on success, a negative AVERROR code on failure
1886 *
1887 * @note Certain muxers and demuxers do nesting, i.e. they open one or more
1888 * additional internal format contexts. Thus the AVFormatContext pointer
1889 * passed to this callback may be different from the one facing the caller.
1890 * It will, however, have the same 'opaque' field.
1891 */
1892 int (*io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url,
1893 int flags, AVDictionary **options);
1894
1895 /**
1896 * A callback for closing the streams opened with AVFormatContext.io_open().
1897 *
1898 * Using this is preferred over io_close, because this can return an error.
1899 * Therefore this callback is used instead of io_close by the generic
1900 * libavformat code if io_close is NULL or the default.
1901 *
1902 * @param s the format context
1903 * @param pb IO context to be closed and freed
1904 * @return 0 on success, a negative AVERROR code on failure
1905 */
1906 int (*io_close2)(struct AVFormatContext *s, AVIOContext *pb);
1907
1908 /**
1909 * Maximum number of bytes read from input in order to determine stream durations
1910 * when using estimate_timings_from_pts in avformat_find_stream_info().
1911 * Demuxing only, set by the caller before avformat_find_stream_info().
1912 * Can be set to 0 to let avformat choose using a heuristic.
1913 *
1914 * @see skip_estimate_duration_from_pts
1915 */
1916 int64_t duration_probesize;
1918
1919/**
1920 * This function will cause global side data to be injected in the next packet
1921 * of each stream as well as after any subsequent seek.
1922 *
1923 * @note global side data is always available in every AVStream's
1924 * @ref AVCodecParameters.coded_side_data "codecpar side data" array, and
1925 * in a @ref AVCodecContext.coded_side_data "decoder's side data" array if
1926 * initialized with said stream's codecpar.
1927 * @see av_packet_side_data_get()
1928 */
1930
1931#if FF_API_GET_DUR_ESTIMATE_METHOD
1932/**
1933 * Returns the method used to set ctx->duration.
1934 *
1935 * @return AVFMT_DURATION_FROM_PTS, AVFMT_DURATION_FROM_STREAM, or AVFMT_DURATION_FROM_BITRATE.
1936 * @deprecated duration_estimation_method is public and can be read directly.
1937 */
1939enum AVDurationEstimationMethod av_fmt_ctx_get_duration_estimation_method(const AVFormatContext* ctx);
1940#endif
1941
1942/**
1943 * @defgroup lavf_core Core functions
1944 * @ingroup libavf
1945 *
1946 * Functions for querying libavformat capabilities, allocating core structures,
1947 * etc.
1948 * @{
1949 */
1950
1951/**
1952 * Return the LIBAVFORMAT_VERSION_INT constant.
1953 */
1954unsigned avformat_version(void);
1955
1956/**
1957 * Return the libavformat build-time configuration.
1958 */
1959const char *avformat_configuration(void);
1960
1961/**
1962 * Return the libavformat license.
1963 */
1964const char *avformat_license(void);
1965
1966/**
1967 * Do global initialization of network libraries. This is optional,
1968 * and not recommended anymore.
1969 *
1970 * This functions only exists to work around thread-safety issues
1971 * with older GnuTLS or OpenSSL libraries. If libavformat is linked
1972 * to newer versions of those libraries, or if you do not use them,
1973 * calling this function is unnecessary. Otherwise, you need to call
1974 * this function before any other threads using them are started.
1975 *
1976 * This function will be deprecated once support for older GnuTLS and
1977 * OpenSSL libraries is removed, and this function has no purpose
1978 * anymore.
1979 */
1980int avformat_network_init(void);
1981
1982/**
1983 * Undo the initialization done by avformat_network_init. Call it only
1984 * once for each time you called avformat_network_init.
1985 */
1986int avformat_network_deinit(void);
1987
1988/**
1989 * Iterate over all registered muxers.
1990 *
1991 * @param opaque a pointer where libavformat will store the iteration state. Must
1992 * point to NULL to start the iteration.
1993 *
1994 * @return the next registered muxer or NULL when the iteration is
1995 * finished
1996 */
1998
1999/**
2000 * Iterate over all registered demuxers.
2001 *
2002 * @param opaque a pointer where libavformat will store the iteration state.
2003 * Must point to NULL to start the iteration.
2004 *
2005 * @return the next registered demuxer or NULL when the iteration is
2006 * finished
2007 */
2009
2010/**
2011 * Allocate an AVFormatContext.
2012 * avformat_free_context() can be used to free the context and everything
2013 * allocated by the framework within it.
2014 */
2016
2017/**
2018 * Free an AVFormatContext and all its streams.
2019 * @param s context to free
2020 */
2022
2023/**
2024 * Get the AVClass for AVFormatContext. It can be used in combination with
2025 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2026 *
2027 * @see av_opt_find().
2028 */
2029const AVClass *avformat_get_class(void);
2030
2031/**
2032 * Get the AVClass for AVStream. It can be used in combination with
2033 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2034 *
2035 * @see av_opt_find().
2036 */
2037const AVClass *av_stream_get_class(void);
2038
2039/**
2040 * Get the AVClass for AVStreamGroup. It can be used in combination with
2041 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2042 *
2043 * @see av_opt_find().
2044 */
2046
2047/**
2048 * @return a string identifying the stream group type, or NULL if unknown
2049 */
2051
2052/**
2053 * Add a new empty stream group to a media file.
2054 *
2055 * When demuxing, it may be called by the demuxer in read_header(). If the
2056 * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
2057 * be called in read_packet().
2058 *
2059 * When muxing, may be called by the user before avformat_write_header().
2060 *
2061 * User is required to call avformat_free_context() to clean up the allocation
2062 * by avformat_stream_group_create().
2063 *
2064 * New streams can be added to the group with avformat_stream_group_add_stream().
2065 *
2066 * @param s media file handle
2067 *
2068 * @return newly created group or NULL on error.
2069 * @see avformat_new_stream, avformat_stream_group_add_stream.
2070 */
2072 enum AVStreamGroupParamsType type,
2073 AVDictionary **options);
2074
2075/**
2076 * Add a new stream to a media file.
2077 *
2078 * When demuxing, it is called by the demuxer in read_header(). If the
2079 * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
2080 * be called in read_packet().
2081 *
2082 * When muxing, should be called by the user before avformat_write_header().
2083 *
2084 * User is required to call avformat_free_context() to clean up the allocation
2085 * by avformat_new_stream().
2086 *
2087 * @param s media file handle
2088 * @param c unused, does nothing
2089 *
2090 * @return newly created stream or NULL on error.
2091 */
2093
2094/**
2095 * Add an already allocated stream to a stream group.
2096 *
2097 * When demuxing, it may be called by the demuxer in read_header(). If the
2098 * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
2099 * be called in read_packet().
2100 *
2101 * When muxing, may be called by the user before avformat_write_header() after
2102 * having allocated a new group with avformat_stream_group_create() and stream with
2103 * avformat_new_stream().
2104 *
2105 * User is required to call avformat_free_context() to clean up the allocation
2106 * by avformat_stream_group_add_stream().
2107 *
2108 * @param stg stream group belonging to a media file.
2109 * @param st stream in the media file to add to the group.
2110 *
2111 * @retval 0 success
2112 * @retval AVERROR(EEXIST) the stream was already in the group
2113 * @retval "another negative error code" legitimate errors
2114 *
2115 * @see avformat_new_stream, avformat_stream_group_create.
2116 */
2118
2119#if FF_API_AVSTREAM_SIDE_DATA
2120/**
2121 * Wrap an existing array as stream side data.
2122 *
2123 * @param st stream
2124 * @param type side information type
2125 * @param data the side data array. It must be allocated with the av_malloc()
2126 * family of functions. The ownership of the data is transferred to
2127 * st.
2128 * @param size side information size
2129 *
2130 * @return zero on success, a negative AVERROR code on failure. On failure,
2131 * the stream is unchanged and the data remains owned by the caller.
2132 * @deprecated use av_packet_side_data_add() with the stream's
2133 * @ref AVCodecParameters.coded_side_data "codecpar side data"
2134 */
2136int av_stream_add_side_data(AVStream *st, enum AVPacketSideDataType type,
2137 uint8_t *data, size_t size);
2138
2139/**
2140 * Allocate new information from stream.
2141 *
2142 * @param stream stream
2143 * @param type desired side information type
2144 * @param size side information size
2145 *
2146 * @return pointer to fresh allocated data or NULL otherwise
2147 * @deprecated use av_packet_side_data_new() with the stream's
2148 * @ref AVCodecParameters.coded_side_data "codecpar side data"
2149 */
2151uint8_t *av_stream_new_side_data(AVStream *stream,
2152 enum AVPacketSideDataType type, size_t size);
2153/**
2154 * Get side information from stream.
2155 *
2156 * @param stream stream
2157 * @param type desired side information type
2158 * @param size If supplied, *size will be set to the size of the side data
2159 * or to zero if the desired side data is not present.
2160 *
2161 * @return pointer to data if present or NULL otherwise
2162 * @deprecated use av_packet_side_data_get() with the stream's
2163 * @ref AVCodecParameters.coded_side_data "codecpar side data"
2164 */
2166uint8_t *av_stream_get_side_data(const AVStream *stream,
2167 enum AVPacketSideDataType type, size_t *size);
2168#endif
2169
2171
2172/**
2173 * @}
2174 */
2175
2176
2177/**
2178 * Allocate an AVFormatContext for an output format.
2179 * avformat_free_context() can be used to free the context and
2180 * everything allocated by the framework within it.
2181 *
2182 * @param ctx pointee is set to the created format context,
2183 * or to NULL in case of failure
2184 * @param oformat format to use for allocating the context, if NULL
2185 * format_name and filename are used instead
2186 * @param format_name the name of output format to use for allocating the
2187 * context, if NULL filename is used instead
2188 * @param filename the name of the filename to use for allocating the
2189 * context, may be NULL
2190 *
2191 * @return >= 0 in case of success, a negative AVERROR code in case of
2192 * failure
2193 */
2195 const char *format_name, const char *filename);
2196
2197/**
2198 * @addtogroup lavf_decoding
2199 * @{
2200 */
2201
2202/**
2203 * Find AVInputFormat based on the short name of the input format.
2204 */
2205const AVInputFormat *av_find_input_format(const char *short_name);
2206
2207/**
2208 * Guess the file format.
2209 *
2210 * @param pd data to be probed
2211 * @param is_opened Whether the file is already opened; determines whether
2212 * demuxers with or without AVFMT_NOFILE are probed.
2213 */
2214const AVInputFormat *av_probe_input_format(const AVProbeData *pd, int is_opened);
2215
2216/**
2217 * Guess the file format.
2218 *
2219 * @param pd data to be probed
2220 * @param is_opened Whether the file is already opened; determines whether
2221 * demuxers with or without AVFMT_NOFILE are probed.
2222 * @param score_max A probe score larger that this is required to accept a
2223 * detection, the variable is set to the actual detection
2224 * score afterwards.
2225 * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
2226 * to retry with a larger probe buffer.
2227 */
2229 int is_opened, int *score_max);
2230
2231/**
2232 * Guess the file format.
2233 *
2234 * @param is_opened Whether the file is already opened; determines whether
2235 * demuxers with or without AVFMT_NOFILE are probed.
2236 * @param score_ret The score of the best detection.
2237 */
2239 int is_opened, int *score_ret);
2240
2241/**
2242 * Probe a bytestream to determine the input format. Each time a probe returns
2243 * with a score that is too low, the probe buffer size is increased and another
2244 * attempt is made. When the maximum probe size is reached, the input format
2245 * with the highest score is returned.
2246 *
2247 * @param pb the bytestream to probe
2248 * @param fmt the input format is put here
2249 * @param url the url of the stream
2250 * @param logctx the log context
2251 * @param offset the offset within the bytestream to probe from
2252 * @param max_probe_size the maximum probe buffer size (zero for default)
2253 *
2254 * @return the score in case of success, a negative value corresponding to an
2255 * the maximal score is AVPROBE_SCORE_MAX
2256 * AVERROR code otherwise
2257 */
2259 const char *url, void *logctx,
2260 unsigned int offset, unsigned int max_probe_size);
2261
2262/**
2263 * Like av_probe_input_buffer2() but returns 0 on success
2264 */
2266 const char *url, void *logctx,
2267 unsigned int offset, unsigned int max_probe_size);
2268
2269/**
2270 * Open an input stream and read the header. The codecs are not opened.
2271 * The stream must be closed with avformat_close_input().
2272 *
2273 * @param ps Pointer to user-supplied AVFormatContext (allocated by
2274 * avformat_alloc_context). May be a pointer to NULL, in
2275 * which case an AVFormatContext is allocated by this
2276 * function and written into ps.
2277 * Note that a user-supplied AVFormatContext will be freed
2278 * on failure.
2279 * @param url URL of the stream to open.
2280 * @param fmt If non-NULL, this parameter forces a specific input format.
2281 * Otherwise the format is autodetected.
2282 * @param options A dictionary filled with AVFormatContext and demuxer-private
2283 * options.
2284 * On return this parameter will be destroyed and replaced with
2285 * a dict containing options that were not found. May be NULL.
2286 *
2287 * @return 0 on success, a negative AVERROR on failure.
2288 *
2289 * @note If you want to use custom IO, preallocate the format context and set its pb field.
2290 */
2291int avformat_open_input(AVFormatContext **ps, const char *url,
2292 const AVInputFormat *fmt, AVDictionary **options);
2293
2294/**
2295 * Read packets of a media file to get stream information. This
2296 * is useful for file formats with no headers such as MPEG. This
2297 * function also computes the real framerate in case of MPEG-2 repeat
2298 * frame mode.
2299 * The logical file position is not changed by this function;
2300 * examined packets may be buffered for later processing.
2301 *
2302 * @param ic media file handle
2303 * @param options If non-NULL, an ic.nb_streams long array of pointers to
2304 * dictionaries, where i-th member contains options for
2305 * codec corresponding to i-th stream.
2306 * On return each dictionary will be filled with options that were not found.
2307 * @return >=0 if OK, AVERROR_xxx on error
2308 *
2309 * @note this function isn't guaranteed to open all the codecs, so
2310 * options being non-empty at return is a perfectly normal behavior.
2311 *
2312 * @todo Let the user decide somehow what information is needed so that
2313 * we do not waste time getting stuff the user does not need.
2314 */
2316
2317/**
2318 * Find the programs which belong to a given stream.
2319 *
2320 * @param ic media file handle
2321 * @param last the last found program, the search will start after this
2322 * program, or from the beginning if it is NULL
2323 * @param s stream index
2324 *
2325 * @return the next program which belongs to s, NULL if no program is found or
2326 * the last program is not among the programs of ic.
2327 */
2329
2330void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx);
2331
2332/**
2333 * Find the "best" stream in the file.
2334 * The best stream is determined according to various heuristics as the most
2335 * likely to be what the user expects.
2336 * If the decoder parameter is non-NULL, av_find_best_stream will find the
2337 * default decoder for the stream's codec; streams for which no decoder can
2338 * be found are ignored.
2339 *
2340 * @param ic media file handle
2341 * @param type stream type: video, audio, subtitles, etc.
2342 * @param wanted_stream_nb user-requested stream number,
2343 * or -1 for automatic selection
2344 * @param related_stream try to find a stream related (eg. in the same
2345 * program) to this one, or -1 if none
2346 * @param decoder_ret if non-NULL, returns the decoder for the
2347 * selected stream
2348 * @param flags flags; none are currently defined
2349 *
2350 * @return the non-negative stream number in case of success,
2351 * AVERROR_STREAM_NOT_FOUND if no stream with the requested type
2352 * could be found,
2353 * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
2354 *
2355 * @note If av_find_best_stream returns successfully and decoder_ret is not
2356 * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
2357 */
2359 enum AVMediaType type,
2360 int wanted_stream_nb,
2361 int related_stream,
2362 const struct AVCodec **decoder_ret,
2363 int flags);
2364
2365/**
2366 * Return the next frame of a stream.
2367 * This function returns what is stored in the file, and does not validate
2368 * that what is there are valid frames for the decoder. It will split what is
2369 * stored in the file into frames and return one for each call. It will not
2370 * omit invalid data between valid frames so as to give the decoder the maximum
2371 * information possible for decoding.
2372 *
2373 * On success, the returned packet is reference-counted (pkt->buf is set) and
2374 * valid indefinitely. The packet must be freed with av_packet_unref() when
2375 * it is no longer needed. For video, the packet contains exactly one frame.
2376 * For audio, it contains an integer number of frames if each frame has
2377 * a known fixed size (e.g. PCM or ADPCM data). If the audio frames have
2378 * a variable size (e.g. MPEG audio), then it contains one frame.
2379 *
2380 * pkt->pts, pkt->dts and pkt->duration are always set to correct
2381 * values in AVStream.time_base units (and guessed if the format cannot
2382 * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
2383 * has B-frames, so it is better to rely on pkt->dts if you do not
2384 * decompress the payload.
2385 *
2386 * @return 0 if OK, < 0 on error or end of file. On error, pkt will be blank
2387 * (as if it came from av_packet_alloc()).
2388 *
2389 * @note pkt will be initialized, so it may be uninitialized, but it must not
2390 * contain data that needs to be freed.
2391 */
2393
2394/**
2395 * Seek to the keyframe at timestamp.
2396 * 'timestamp' in 'stream_index'.
2397 *
2398 * @param s media file handle
2399 * @param stream_index If stream_index is (-1), a default stream is selected,
2400 * and timestamp is automatically converted from
2401 * AV_TIME_BASE units to the stream specific time_base.
2402 * @param timestamp Timestamp in AVStream.time_base units or, if no stream
2403 * is specified, in AV_TIME_BASE units.
2404 * @param flags flags which select direction and seeking mode
2405 *
2406 * @return >= 0 on success
2407 */
2408int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
2409 int flags);
2410
2411/**
2412 * Seek to timestamp ts.
2413 * Seeking will be done so that the point from which all active streams
2414 * can be presented successfully will be closest to ts and within min/max_ts.
2415 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
2416 *
2417 * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
2418 * are the file position (this may not be supported by all demuxers).
2419 * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
2420 * in the stream with stream_index (this may not be supported by all demuxers).
2421 * Otherwise all timestamps are in units of the stream selected by stream_index
2422 * or if stream_index is -1, in AV_TIME_BASE units.
2423 * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
2424 * keyframes (this may not be supported by all demuxers).
2425 * If flags contain AVSEEK_FLAG_BACKWARD, it is ignored.
2426 *
2427 * @param s media file handle
2428 * @param stream_index index of the stream which is used as time base reference
2429 * @param min_ts smallest acceptable timestamp
2430 * @param ts target timestamp
2431 * @param max_ts largest acceptable timestamp
2432 * @param flags flags
2433 * @return >=0 on success, error code otherwise
2434 *
2435 * @note This is part of the new seek API which is still under construction.
2436 */
2437int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
2438
2439/**
2440 * Discard all internally buffered data. This can be useful when dealing with
2441 * discontinuities in the byte stream. Generally works only with formats that
2442 * can resync. This includes headerless formats like MPEG-TS/TS but should also
2443 * work with NUT, Ogg and in a limited way AVI for example.
2444 *
2445 * The set of streams, the detected duration, stream parameters and codecs do
2446 * not change when calling this function. If you want a complete reset, it's
2447 * better to open a new AVFormatContext.
2448 *
2449 * This does not flush the AVIOContext (s->pb). If necessary, call
2450 * avio_flush(s->pb) before calling this function.
2451 *
2452 * @param s media file handle
2453 * @return >=0 on success, error code otherwise
2454 */
2456
2457/**
2458 * Start playing a network-based stream (e.g. RTSP stream) at the
2459 * current position.
2460 */
2462
2463/**
2464 * Pause a network-based stream (e.g. RTSP stream).
2465 *
2466 * Use av_read_play() to resume it.
2467 */
2469
2470/**
2471 * Close an opened input AVFormatContext. Free it and all its contents
2472 * and set *s to NULL.
2473 */
2475/**
2476 * @}
2479#define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
2480#define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
2481#define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
2482#define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
2483
2484/**
2485 * @addtogroup lavf_encoding
2486 * @{
2489#define AVSTREAM_INIT_IN_WRITE_HEADER 0 ///< stream parameters initialized in avformat_write_header
2490#define AVSTREAM_INIT_IN_INIT_OUTPUT 1 ///< stream parameters initialized in avformat_init_output
2491
2492/**
2493 * Allocate the stream private data and write the stream header to
2494 * an output media file.
2495 *
2496 * @param s Media file handle, must be allocated with
2497 * avformat_alloc_context().
2498 * Its \ref AVFormatContext.oformat "oformat" field must be set
2499 * to the desired output format;
2500 * Its \ref AVFormatContext.pb "pb" field must be set to an
2501 * already opened ::AVIOContext.
2502 * @param options An ::AVDictionary filled with AVFormatContext and
2503 * muxer-private options.
2504 * On return this parameter will be destroyed and replaced with
2505 * a dict containing options that were not found. May be NULL.
2506 *
2507 * @retval AVSTREAM_INIT_IN_WRITE_HEADER On success, if the codec had not already been
2508 * fully initialized in avformat_init_output().
2509 * @retval AVSTREAM_INIT_IN_INIT_OUTPUT On success, if the codec had already been fully
2510 * initialized in avformat_init_output().
2511 * @retval AVERROR A negative AVERROR on failure.
2512 *
2513 * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_init_output.
2517
2518/**
2519 * Allocate the stream private data and initialize the codec, but do not write the header.
2520 * May optionally be used before avformat_write_header() to initialize stream parameters
2521 * before actually writing the header.
2522 * If using this function, do not pass the same options to avformat_write_header().
2523 *
2524 * @param s Media file handle, must be allocated with
2525 * avformat_alloc_context().
2526 * Its \ref AVFormatContext.oformat "oformat" field must be set
2527 * to the desired output format;
2528 * Its \ref AVFormatContext.pb "pb" field must be set to an
2529 * already opened ::AVIOContext.
2530 * @param options An ::AVDictionary filled with AVFormatContext and
2531 * muxer-private options.
2532 * On return this parameter will be destroyed and replaced with
2533 * a dict containing options that were not found. May be NULL.
2534 *
2535 * @retval AVSTREAM_INIT_IN_WRITE_HEADER On success, if the codec requires
2536 * avformat_write_header to fully initialize.
2537 * @retval AVSTREAM_INIT_IN_INIT_OUTPUT On success, if the codec has been fully
2538 * initialized.
2539 * @retval AVERROR Anegative AVERROR on failure.
2540 *
2541 * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_write_header.
2545
2546/**
2547 * Write a packet to an output media file.
2548 *
2549 * This function passes the packet directly to the muxer, without any buffering
2550 * or reordering. The caller is responsible for correctly interleaving the
2551 * packets if the format requires it. Callers that want libavformat to handle
2552 * the interleaving should call av_interleaved_write_frame() instead of this
2553 * function.
2554 *
2555 * @param s media file handle
2556 * @param pkt The packet containing the data to be written. Note that unlike
2557 * av_interleaved_write_frame(), this function does not take
2558 * ownership of the packet passed to it (though some muxers may make
2559 * an internal reference to the input packet).
2560 * <br>
2561 * This parameter can be NULL (at any time, not just at the end), in
2562 * order to immediately flush data buffered within the muxer, for
2563 * muxers that buffer up data internally before writing it to the
2564 * output.
2565 * <br>
2566 * Packet's @ref AVPacket.stream_index "stream_index" field must be
2567 * set to the index of the corresponding stream in @ref
2568 * AVFormatContext.streams "s->streams".
2569 * <br>
2570 * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2571 * must be set to correct values in the stream's timebase (unless the
2572 * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2573 * they can be set to AV_NOPTS_VALUE).
2574 * The dts for subsequent packets passed to this function must be strictly
2575 * increasing when compared in their respective timebases (unless the
2576 * output format is flagged with the AVFMT_TS_NONSTRICT, then they
2577 * merely have to be nondecreasing). @ref AVPacket.duration
2578 * "duration") should also be set if known.
2579 * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush
2580 *
2581 * @see av_interleaved_write_frame()
2582 */
2584
2585/**
2586 * Write a packet to an output media file ensuring correct interleaving.
2587 *
2588 * This function will buffer the packets internally as needed to make sure the
2589 * packets in the output file are properly interleaved, usually ordered by
2590 * increasing dts. Callers doing their own interleaving should call
2591 * av_write_frame() instead of this function.
2592 *
2593 * Using this function instead of av_write_frame() can give muxers advance
2594 * knowledge of future packets, improving e.g. the behaviour of the mp4
2595 * muxer for VFR content in fragmenting mode.
2596 *
2597 * @param s media file handle
2598 * @param pkt The packet containing the data to be written.
2599 * <br>
2600 * If the packet is reference-counted, this function will take
2601 * ownership of this reference and unreference it later when it sees
2602 * fit. If the packet is not reference-counted, libavformat will
2603 * make a copy.
2604 * The returned packet will be blank (as if returned from
2605 * av_packet_alloc()), even on error.
2606 * <br>
2607 * This parameter can be NULL (at any time, not just at the end), to
2608 * flush the interleaving queues.
2609 * <br>
2610 * Packet's @ref AVPacket.stream_index "stream_index" field must be
2611 * set to the index of the corresponding stream in @ref
2612 * AVFormatContext.streams "s->streams".
2613 * <br>
2614 * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2615 * must be set to correct values in the stream's timebase (unless the
2616 * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2617 * they can be set to AV_NOPTS_VALUE).
2618 * The dts for subsequent packets in one stream must be strictly
2619 * increasing (unless the output format is flagged with the
2620 * AVFMT_TS_NONSTRICT, then they merely have to be nondecreasing).
2621 * @ref AVPacket.duration "duration" should also be set if known.
2622 *
2623 * @return 0 on success, a negative AVERROR on error.
2624 *
2625 * @see av_write_frame(), AVFormatContext.max_interleave_delta
2626 */
2628
2629/**
2630 * Write an uncoded frame to an output media file.
2631 *
2632 * The frame must be correctly interleaved according to the container
2633 * specification; if not, av_interleaved_write_uncoded_frame() must be used.
2634 *
2635 * See av_interleaved_write_uncoded_frame() for details.
2636 */
2637int av_write_uncoded_frame(AVFormatContext *s, int stream_index,
2638 struct AVFrame *frame);
2639
2640/**
2641 * Write an uncoded frame to an output media file.
2642 *
2643 * If the muxer supports it, this function makes it possible to write an AVFrame
2644 * structure directly, without encoding it into a packet.
2645 * It is mostly useful for devices and similar special muxers that use raw
2646 * video or PCM data and will not serialize it into a byte stream.
2647 *
2648 * To test whether it is possible to use it with a given muxer and stream,
2649 * use av_write_uncoded_frame_query().
2650 *
2651 * The caller gives up ownership of the frame and must not access it
2652 * afterwards.
2653 *
2654 * @return >=0 for success, a negative code on error
2655 */
2657 struct AVFrame *frame);
2658
2659/**
2660 * Test whether a muxer supports uncoded frame.
2661 *
2662 * @return >=0 if an uncoded frame can be written to that muxer and stream,
2663 * <0 if not
2664 */
2665int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index);
2666
2667/**
2668 * Write the stream trailer to an output media file and free the
2669 * file private data.
2670 *
2671 * May only be called after a successful call to avformat_write_header.
2672 *
2673 * @param s media file handle
2674 * @return 0 if OK, AVERROR_xxx on error
2675 */
2677
2678/**
2679 * Return the output format in the list of registered output formats
2680 * which best matches the provided parameters, or return NULL if
2681 * there is no match.
2682 *
2683 * @param short_name if non-NULL checks if short_name matches with the
2684 * names of the registered formats
2685 * @param filename if non-NULL checks if filename terminates with the
2686 * extensions of the registered formats
2687 * @param mime_type if non-NULL checks if mime_type matches with the
2688 * MIME type of the registered formats
2689 */
2690const AVOutputFormat *av_guess_format(const char *short_name,
2691 const char *filename,
2692 const char *mime_type);
2693
2694/**
2695 * Guess the codec ID based upon muxer and filename.
2696 */
2697enum AVCodecID av_guess_codec(const AVOutputFormat *fmt, const char *short_name,
2698 const char *filename, const char *mime_type,
2699 enum AVMediaType type);
2700
2701/**
2702 * Get timing information for the data currently output.
2703 * The exact meaning of "currently output" depends on the format.
2704 * It is mostly relevant for devices that have an internal buffer and/or
2705 * work in real time.
2706 * @param s media file handle
2707 * @param stream stream in the media file
2708 * @param[out] dts DTS of the last packet output for the stream, in stream
2709 * time_base units
2710 * @param[out] wall absolute time when that packet whas output,
2711 * in microsecond
2712 * @retval 0 Success
2713 * @retval AVERROR(ENOSYS) The format does not support it
2714 *
2715 * @note Some formats or devices may not allow to measure dts and wall
2716 * atomically.
2717 */
2718int av_get_output_timestamp(struct AVFormatContext *s, int stream,
2719 int64_t *dts, int64_t *wall);
2720
2721
2722/**
2723 * @}
2724 */
2725
2726
2727/**
2728 * @defgroup lavf_misc Utility functions
2729 * @ingroup libavf
2730 * @{
2731 *
2732 * Miscellaneous utility functions related to both muxing and demuxing
2733 * (or neither).
2734 */
2735
2736/**
2737 * Send a nice hexadecimal dump of a buffer to the specified file stream.
2738 *
2739 * @param f The file stream pointer where the dump should be sent to.
2740 * @param buf buffer
2741 * @param size buffer size
2742 *
2743 * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2
2744 */
2745void av_hex_dump(FILE *f, const uint8_t *buf, int size);
2746
2747/**
2748 * Send a nice hexadecimal dump of a buffer to the log.
2749 *
2750 * @param avcl A pointer to an arbitrary struct of which the first field is a
2751 * pointer to an AVClass struct.
2752 * @param level The importance level of the message, lower values signifying
2753 * higher importance.
2754 * @param buf buffer
2755 * @param size buffer size
2756 *
2757 * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2
2758 */
2759void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size);
2760
2761/**
2762 * Send a nice dump of a packet to the specified file stream.
2763 *
2764 * @param f The file stream pointer where the dump should be sent to.
2765 * @param pkt packet to dump
2766 * @param dump_payload True if the payload must be displayed, too.
2767 * @param st AVStream that the packet belongs to
2768 */
2769void av_pkt_dump2(FILE *f, const AVPacket *pkt, int dump_payload, const AVStream *st);
2770
2771
2772/**
2773 * Send a nice dump of a packet to the log.
2774 *
2775 * @param avcl A pointer to an arbitrary struct of which the first field is a
2776 * pointer to an AVClass struct.
2777 * @param level The importance level of the message, lower values signifying
2778 * higher importance.
2779 * @param pkt packet to dump
2780 * @param dump_payload True if the payload must be displayed, too.
2781 * @param st AVStream that the packet belongs to
2782 */
2783void av_pkt_dump_log2(void *avcl, int level, const AVPacket *pkt, int dump_payload,
2784 const AVStream *st);
2785
2786/**
2787 * Get the AVCodecID for the given codec tag tag.
2788 * If no codec id is found returns AV_CODEC_ID_NONE.
2789 *
2790 * @param tags list of supported codec_id-codec_tag pairs, as stored
2791 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2792 * @param tag codec tag to match to a codec ID
2793 */
2794enum AVCodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
2795
2796/**
2797 * Get the codec tag for the given codec id id.
2798 * If no codec tag is found returns 0.
2799 *
2800 * @param tags list of supported codec_id-codec_tag pairs, as stored
2801 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2802 * @param id codec ID to match to a codec tag
2803 */
2804unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id);
2805
2806/**
2807 * Get the codec tag for the given codec id.
2808 *
2809 * @param tags list of supported codec_id - codec_tag pairs, as stored
2810 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2811 * @param id codec id that should be searched for in the list
2812 * @param tag A pointer to the found tag
2813 * @return 0 if id was not found in tags, > 0 if it was found
2814 */
2815int av_codec_get_tag2(const struct AVCodecTag * const *tags, enum AVCodecID id,
2816 unsigned int *tag);
2817
2819
2820/**
2821 * Get the index for a specific timestamp.
2822 *
2823 * @param st stream that the timestamp belongs to
2824 * @param timestamp timestamp to retrieve the index for
2825 * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
2826 * to the timestamp which is <= the requested one, if backward
2827 * is 0, then it will be >=
2828 * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
2829 * @return < 0 if no such timestamp could be found
2830 */
2831int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
2832
2833/**
2834 * Get the index entry count for the given AVStream.
2835 *
2836 * @param st stream
2837 * @return the number of index entries in the stream
2838 */
2840
2841/**
2842 * Get the AVIndexEntry corresponding to the given index.
2843 *
2844 * @param st Stream containing the requested AVIndexEntry.
2845 * @param idx The desired index.
2846 * @return A pointer to the requested AVIndexEntry if it exists, NULL otherwise.
2847 *
2848 * @note The pointer returned by this function is only guaranteed to be valid
2849 * until any function that takes the stream or the parent AVFormatContext
2850 * as input argument is called.
2851 */
2853
2854/**
2855 * Get the AVIndexEntry corresponding to the given timestamp.
2856 *
2857 * @param st Stream containing the requested AVIndexEntry.
2858 * @param wanted_timestamp Timestamp to retrieve the index entry for.
2859 * @param flags If AVSEEK_FLAG_BACKWARD then the returned entry will correspond
2860 * to the timestamp which is <= the requested one, if backward
2861 * is 0, then it will be >=
2862 * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise.
2863 * @return A pointer to the requested AVIndexEntry if it exists, NULL otherwise.
2864 *
2865 * @note The pointer returned by this function is only guaranteed to be valid
2866 * until any function that takes the stream or the parent AVFormatContext
2867 * as input argument is called.
2868 */
2870 int64_t wanted_timestamp,
2871 int flags);
2872/**
2873 * Add an index entry into a sorted list. Update the entry if the list
2874 * already contains it.
2875 *
2876 * @param timestamp timestamp in the time base of the given stream
2877 */
2878int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
2879 int size, int distance, int flags);
2880
2881
2882/**
2883 * Split a URL string into components.
2884 *
2885 * The pointers to buffers for storing individual components may be null,
2886 * in order to ignore that component. Buffers for components not found are
2887 * set to empty strings. If the port is not found, it is set to a negative
2888 * value.
2889 *
2890 * @param proto the buffer for the protocol
2891 * @param proto_size the size of the proto buffer
2892 * @param authorization the buffer for the authorization
2893 * @param authorization_size the size of the authorization buffer
2894 * @param hostname the buffer for the host name
2895 * @param hostname_size the size of the hostname buffer
2896 * @param port_ptr a pointer to store the port number in
2897 * @param path the buffer for the path
2898 * @param path_size the size of the path buffer
2899 * @param url the URL to split
2900 */
2901void av_url_split(char *proto, int proto_size,
2902 char *authorization, int authorization_size,
2903 char *hostname, int hostname_size,
2904 int *port_ptr,
2905 char *path, int path_size,
2906 const char *url);
2907
2908
2909/**
2910 * Print detailed information about the input or output format, such as
2911 * duration, bitrate, streams, container, programs, metadata, side data,
2912 * codec and time base.
2913 *
2914 * @param ic the context to analyze
2915 * @param index index of the stream to dump information about
2916 * @param url the URL to print, such as source or destination file
2917 * @param is_output Select whether the specified context is an input(0) or output(1)
2918 */
2920 int index,
2921 const char *url,
2922 int is_output);
2924
2925#define AV_FRAME_FILENAME_FLAGS_MULTIPLE 1 ///< Allow multiple %d
2926
2927/**
2928 * Return in 'buf' the path with '%d' replaced by a number.
2929 *
2930 * Also handles the '%0nd' format where 'n' is the total number
2931 * of digits and '%%'.
2932 *
2933 * @param buf destination buffer
2934 * @param buf_size destination buffer size
2935 * @param path numbered sequence string
2936 * @param number frame number
2937 * @param flags AV_FRAME_FILENAME_FLAGS_*
2938 * @return 0 if OK, -1 on format error
2939 */
2940int av_get_frame_filename2(char *buf, int buf_size,
2941 const char *path, int number, int flags);
2942
2943int av_get_frame_filename(char *buf, int buf_size,
2944 const char *path, int number);
2945
2946/**
2947 * Check whether filename actually is a numbered sequence generator.
2948 *
2949 * @param filename possible numbered sequence string
2950 * @return 1 if a valid numbered sequence string, 0 otherwise
2951 */
2952int av_filename_number_test(const char *filename);
2953
2954/**
2955 * Generate an SDP for an RTP session.
2956 *
2957 * Note, this overwrites the id values of AVStreams in the muxer contexts
2958 * for getting unique dynamic payload types.
2959 *
2960 * @param ac array of AVFormatContexts describing the RTP streams. If the
2961 * array is composed by only one context, such context can contain
2962 * multiple AVStreams (one AVStream per RTP stream). Otherwise,
2963 * all the contexts in the array (an AVCodecContext per RTP stream)
2964 * must contain only one AVStream.
2965 * @param n_files number of AVCodecContexts contained in ac
2966 * @param buf buffer where the SDP will be stored (must be allocated by
2967 * the caller)
2968 * @param size the size of the buffer
2969 * @return 0 if OK, AVERROR_xxx on error
2970 */
2971int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size);
2972
2973/**
2974 * Return a positive value if the given filename has one of the given
2975 * extensions, 0 otherwise.
2976 *
2977 * @param filename file name to check against the given extensions
2978 * @param extensions a comma-separated list of filename extensions
2979 */
2980int av_match_ext(const char *filename, const char *extensions);
2981
2982/**
2983 * Test if the given container can store a codec.
2984 *
2985 * @param ofmt container to check for compatibility
2986 * @param codec_id codec to potentially store in container
2987 * @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
2988 *
2989 * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
2990 * A negative number if this information is not available.
2991 */
2992int avformat_query_codec(const AVOutputFormat *ofmt, enum AVCodecID codec_id,
2993 int std_compliance);
2994
2995/**
2996 * @defgroup riff_fourcc RIFF FourCCs
2997 * @{
2998 * Get the tables mapping RIFF FourCCs to libavcodec AVCodecIDs. The tables are
2999 * meant to be passed to av_codec_get_id()/av_codec_get_tag() as in the
3000 * following code:
3001 * @code
3002 * uint32_t tag = MKTAG('H', '2', '6', '4');
3003 * const struct AVCodecTag *table[] = { avformat_get_riff_video_tags(), 0 };
3004 * enum AVCodecID id = av_codec_get_id(table, tag);
3005 * @endcode
3006 */
3007/**
3008 * @return the table mapping RIFF FourCCs for video to libavcodec AVCodecID.
3009 */
3010const struct AVCodecTag *avformat_get_riff_video_tags(void);
3011/**
3012 * @return the table mapping RIFF FourCCs for audio to AVCodecID.
3013 */
3014const struct AVCodecTag *avformat_get_riff_audio_tags(void);
3015/**
3016 * @return the table mapping MOV FourCCs for video to libavcodec AVCodecID.
3017 */
3018const struct AVCodecTag *avformat_get_mov_video_tags(void);
3019/**
3020 * @return the table mapping MOV FourCCs for audio to AVCodecID.
3021 */
3022const struct AVCodecTag *avformat_get_mov_audio_tags(void);
3023
3024/**
3025 * @}
3026 */
3027
3028/**
3029 * Guess the sample aspect ratio of a frame, based on both the stream and the
3030 * frame aspect ratio.
3031 *
3032 * Since the frame aspect ratio is set by the codec but the stream aspect ratio
3033 * is set by the demuxer, these two may not be equal. This function tries to
3034 * return the value that you should use if you would like to display the frame.
3035 *
3036 * Basic logic is to use the stream aspect ratio if it is set to something sane
3037 * otherwise use the frame aspect ratio. This way a container setting, which is
3038 * usually easy to modify can override the coded value in the frames.
3039 *
3040 * @param format the format context which the stream is part of
3041 * @param stream the stream which the frame is part of
3042 * @param frame the frame with the aspect ratio to be determined
3043 * @return the guessed (valid) sample_aspect_ratio, 0/1 if no idea
3044 */
3046 struct AVFrame *frame);
3047
3048/**
3049 * Guess the frame rate, based on both the container and codec information.
3050 *
3051 * @param ctx the format context which the stream is part of
3052 * @param stream the stream which the frame is part of
3053 * @param frame the frame for which the frame rate should be determined, may be NULL
3054 * @return the guessed (valid) frame rate, 0/1 if no idea
3055 */
3057 struct AVFrame *frame);
3058
3059/**
3060 * Check if the stream st contained in s is matched by the stream specifier
3061 * spec.
3062 *
3063 * See the "stream specifiers" chapter in the documentation for the syntax
3064 * of spec.
3065 *
3066 * @return >0 if st is matched by spec;
3067 * 0 if st is not matched by spec;
3068 * AVERROR code if spec is invalid
3069 *
3070 * @note A stream specifier can match several streams in the format.
3071 */
3073 const char *spec);
3074
3076
3077#if FF_API_INTERNAL_TIMING
3078enum AVTimebaseSource {
3079 AVFMT_TBCF_AUTO = -1,
3080 AVFMT_TBCF_DECODER,
3081 AVFMT_TBCF_DEMUXER,
3082#if FF_API_R_FRAME_RATE
3083 AVFMT_TBCF_R_FRAMERATE,
3084#endif
3085};
3086
3087/**
3088 * @deprecated do not call this function
3089 */
3091int avformat_transfer_internal_stream_timing_info(const AVOutputFormat *ofmt,
3092 AVStream *ost, const AVStream *ist,
3093 enum AVTimebaseSource copy_tb);
3094
3095/**
3096 * @deprecated do not call this function
3097 */
3099AVRational av_stream_get_codec_timebase(const AVStream *st);
3100#endif
3101
3102
3103/**
3104 * @}
3105 */
3106
3107#endif /* AVFORMAT_AVFORMAT_H */
#define av_warn_unused_result
Definition attributes.h:62
#define attribute_deprecated
Definition attributes.h:100
int av_append_packet(AVIOContext *s, AVPacket *pkt, int size)
Read data and append it to the current content of the AVPacket.
AVStreamGroupParamsType
Definition avformat.h:1110
@ AV_STREAM_GROUP_PARAMS_NONE
Definition avformat.h:1111
@ AV_STREAM_GROUP_PARAMS_IAMF_MIX_PRESENTATION
Definition avformat.h:1113
@ AV_STREAM_GROUP_PARAMS_TILE_GRID
Definition avformat.h:1114
@ AV_STREAM_GROUP_PARAMS_IAMF_AUDIO_ELEMENT
Definition avformat.h:1112
@ AV_STREAM_GROUP_PARAMS_LCEVC
Definition avformat.h:1115
int(* AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options)
Definition avformat.h:1260
AVDurationEstimationMethod
The duration of a video can be estimated through various ways, and this enum can be used to know how ...
Definition avformat.h:1267
@ AVFMT_DURATION_FROM_BITRATE
Duration estimated from bitrate (less accurate)
Definition avformat.h:1270
@ AVFMT_DURATION_FROM_PTS
Duration accurately estimated from PTSes.
Definition avformat.h:1268
@ AVFMT_DURATION_FROM_STREAM
Duration estimated from a stream with a known duration.
Definition avformat.h:1269
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:1257
const char * av_disposition_to_string(int disposition)
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.
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...
int av_disposition_from_string(const char *disp)
struct AVCodecParserContext * av_stream_get_parser(const AVStream *s)
int avformat_alloc_output_context2(AVFormatContext **ctx, const AVOutputFormat *oformat, const char *format_name, const char *filename)
Allocate an AVFormatContext for an output format.
AVStreamParseType
Definition avformat.h:591
@ AVSTREAM_PARSE_TIMESTAMPS
full parsing and interpolation of timestamps for frames not starting on a packet boundary
Definition avformat.h:595
@ AVSTREAM_PARSE_FULL_ONCE
full parsing and repack of the first frame only, only implemented for H.264 currently
Definition avformat.h:596
@ AVSTREAM_PARSE_FULL_RAW
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition avformat.h:597
@ AVSTREAM_PARSE_HEADERS
Only parse headers, do not repack.
Definition avformat.h:594
@ AVSTREAM_PARSE_FULL
full parsing and repack
Definition avformat.h:593
@ AVSTREAM_PARSE_NONE
Definition avformat.h:592
Buffered I/O operations.
Misc types and constants that do not belong anywhere else.
static AVPacket * pkt
static AVFrame * frame
Public dictionary API.
reference-counted frame API
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition codec_id.h:49
AVDiscard
Definition defs.h:212
AVPacketSideDataType
Definition packet.h:41
const AVClass * av_stream_group_get_class(void)
Get the AVClass for AVStreamGroup.
int avformat_network_deinit(void)
Undo the initialization done by avformat_network_init.
const char * avformat_configuration(void)
Return the libavformat build-time configuration.
const char * avformat_stream_group_name(enum AVStreamGroupParamsType type)
AVProgram * av_new_program(AVFormatContext *s, int id)
AVStreamGroup * avformat_stream_group_create(AVFormatContext *s, enum AVStreamGroupParamsType type, AVDictionary **options)
Add a new empty stream group to a media file.
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
const AVClass * av_stream_get_class(void)
Get the AVClass for AVStream.
int avformat_stream_group_add_stream(AVStreamGroup *stg, AVStream *st)
Add an already allocated stream to a stream group.
const AVOutputFormat * av_muxer_iterate(void **opaque)
Iterate over all registered muxers.
int avformat_network_init(void)
Do global initialization of network libraries.
const char * avformat_license(void)
Return the libavformat license.
AVFormatContext * avformat_alloc_context(void)
Allocate an AVFormatContext.
const AVInputFormat * av_demuxer_iterate(void **opaque)
Iterate over all registered demuxers.
void avformat_free_context(AVFormatContext *s)
Free an AVFormatContext and all its streams.
const AVClass * avformat_get_class(void)
Get the AVClass for AVFormatContext.
unsigned avformat_version(void)
Return the LIBAVFORMAT_VERSION_INT constant.
const AVInputFormat * av_find_input_format(const char *short_name)
Find AVInputFormat based on the short name of the input format.
AVProgram * av_find_program_from_stream(AVFormatContext *ic, AVProgram *last, int s)
Find the programs which belong to a given stream.
const AVInputFormat * av_probe_input_format3(const AVProbeData *pd, int is_opened, int *score_ret)
Guess the file format.
int av_read_pause(AVFormatContext *s)
Pause a network-based stream (e.g.
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.
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
int av_read_play(AVFormatContext *s)
Start playing a network-based stream (e.g.
int av_find_best_stream(AVFormatContext *ic, enum AVMediaType type, int wanted_stream_nb, int related_stream, const struct AVCodec **decoder_ret, int flags)
Find the "best" stream in the file.
int av_probe_input_buffer(AVIOContext *pb, const AVInputFormat **fmt, const char *url, void *logctx, unsigned int offset, unsigned int max_probe_size)
Like av_probe_input_buffer2() but returns 0 on success.
int avformat_flush(AVFormatContext *s)
Discard all internally buffered data.
int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Seek to the keyframe at timestamp.
void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx)
int av_probe_input_buffer2(AVIOContext *pb, const AVInputFormat **fmt, const char *url, void *logctx, unsigned int offset, unsigned int max_probe_size)
Probe a bytestream to determine the input format.
int avformat_open_input(AVFormatContext **ps, const char *url, const AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
const AVInputFormat * av_probe_input_format(const AVProbeData *pd, int is_opened)
Guess the file format.
const AVInputFormat * av_probe_input_format2(const AVProbeData *pd, int is_opened, int *score_max)
Guess the file format.
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
enum AVCodecID av_guess_codec(const AVOutputFormat *fmt, const char *short_name, const char *filename, const char *mime_type, enum AVMediaType type)
Guess the codec ID based upon muxer and filename.
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.
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.
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file ensuring correct interleaving.
int av_interleaved_write_uncoded_frame(AVFormatContext *s, int stream_index, struct AVFrame *frame)
Write an uncoded frame to an output media file.
int av_write_uncoded_frame(AVFormatContext *s, int stream_index, struct AVFrame *frame)
Write an uncoded frame to an output media file.
int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index)
Test whether a muxer supports uncoded frame.
int av_get_output_timestamp(struct AVFormatContext *s, int stream, int64_t *dts, int64_t *wall)
Get timing information for the data currently output.
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
const AVOutputFormat * av_guess_format(const char *short_name, const char *filename, const char *mime_type)
Return the output format in the list of registered output formats which best matches the provided par...
int av_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file.
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.
unsigned int av_codec_get_tag(const struct AVCodecTag *const *tags, enum AVCodecID id)
Get the codec tag for the given codec id id.
enum AVCodecID av_codec_get_id(const struct AVCodecTag *const *tags, unsigned int tag)
Get the AVCodecID for the given codec tag tag.
int avformat_index_get_entries_count(const AVStream *st)
Get the index entry count for the given AVStream.
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.
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.
int avformat_queue_attached_pictures(AVFormatContext *s)
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.
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.
const AVIndexEntry * avformat_index_get_entry(AVStream *st, int idx)
Get the AVIndexEntry corresponding to the given index.
AVRational av_guess_frame_rate(AVFormatContext *ctx, AVStream *stream, struct AVFrame *frame)
Guess the frame rate, based on both the container and codec information.
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.
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.
int av_get_frame_filename(char *buf, int buf_size, const char *path, int number)
int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size)
Generate an SDP for an RTP session.
int avformat_query_codec(const AVOutputFormat *ofmt, enum AVCodecID codec_id, int std_compliance)
Test if the given container can store a codec.
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.
int av_find_default_stream_index(AVFormatContext *s)
const AVIndexEntry * avformat_index_get_entry_from_timestamp(AVStream *st, int64_t wanted_timestamp, int flags)
Get the AVIndexEntry corresponding to the given timestamp.
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.
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.
int av_filename_number_test(const char *filename)
Check whether filename actually is a numbered sequence generator.
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
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,...
AVRational av_guess_sample_aspect_ratio(AVFormatContext *format, AVStream *stream, struct AVFrame *frame)
Guess the sample aspect ratio of a frame, based on both the stream and the frame aspect ratio.
struct AVDictionary AVDictionary
Definition dict.h:94
AVMediaType
Definition avutil.h:199
const struct AVCodecTag * avformat_get_mov_audio_tags(void)
const struct AVCodecTag * avformat_get_riff_audio_tags(void)
const struct AVCodecTag * avformat_get_mov_video_tags(void)
const struct AVCodecTag * avformat_get_riff_video_tags(void)
Libavformat version macros.
Libavformat version macros.
int64_t id
unique ID to identify the chapter
Definition avformat.h:1247
int64_t start
Definition avformat.h:1249
AVDictionary * metadata
Definition avformat.h:1250
int64_t end
chapter start/end time in time_base units
Definition avformat.h:1249
AVRational time_base
time base in which the start/end timestamps are specified
Definition avformat.h:1248
Describe the class of an AVClass context structure.
Definition log.h:66
This struct describes the properties of an encoded stream.
Definition codec_par.h:47
AVCodec.
Definition codec.h:187
Format I/O context.
Definition avformat.h:1287
int64_t max_interleave_delta
Maximum buffering duration for interleaving.
Definition avformat.h:1609
int event_flags
Flags indicating events happening on the file, a combination of AVFMT_EVENT_FLAG_*.
Definition avformat.h:1657
int avoid_negative_ts
Avoid negative timestamps during muxing.
Definition avformat.h:1674
unsigned int packet_size
Definition avformat.h:1431
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition avformat.h:1343
const AVClass * av_class
A class for logging and AVOptions.
Definition avformat.h:1292
int max_streams
The maximum number of streams.
Definition avformat.h:1573
int(* io_close2)(struct AVFormatContext *s, AVIOContext *pb)
A callback for closing the streams opened with AVFormatContext.io_open().
Definition avformat.h:1904
const uint8_t * key
Definition avformat.h:1484
AVStreamGroup ** stream_groups
A list of all stream groups in the file.
Definition avformat.h:1374
enum AVCodecID audio_codec_id
Forced audio codec_id.
Definition avformat.h:1500
AVIOContext * pb
I/O context.
Definition avformat.h:1329
int flush_packets
Flush the I/O context after each packet.
Definition avformat.h:1746
enum AVCodecID data_codec_id
Forced Data codec_id.
Definition avformat.h:1512
int64_t start_time
Position of the first frame of the component, in AV_TIME_BASE fractional seconds.
Definition avformat.h:1412
const struct AVCodec * data_codec
Forced data codec.
Definition avformat.h:1836
AVDictionary * metadata
Metadata that applies to the whole file.
Definition avformat.h:1522
int flags
Flags modifying the (de)muxer behaviour.
Definition avformat.h:1438
const struct AVOutputFormat * oformat
The output container format.
Definition avformat.h:1306
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:1631
int seek2any
Force seeking to any (also non key) frames.
Definition avformat.h:1739
int io_repositioned
IO repositioned flag.
Definition avformat.h:1804
AVProgram ** programs
Definition avformat.h:1488
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:1482
int ctx_flags
Flags signalling stream properties.
Definition avformat.h:1336
int strict_std_compliance
Allow non-standard and experimental extension.
Definition avformat.h:1644
int fps_probe_size
The number of frames used for determining the framerate in avformat_find_stream_info().
Definition avformat.h:1542
const struct AVCodec * audio_codec
Forced audio codec.
Definition avformat.h:1820
unsigned int nb_programs
Definition avformat.h:1487
AVIOInterruptCB interrupt_callback
Custom interrupt callbacks for the I/O layer.
Definition avformat.h:1560
int avio_flags
avio flags, used to force AVIO_FLAG_DIRECT.
Definition avformat.h:1710
char * url
input or output URL.
Definition avformat.h:1403
int probe_score
format probing score.
Definition avformat.h:1755
const struct AVInputFormat * iformat
The input container format.
Definition avformat.h:1299
unsigned int nb_chapters
Number of chapters in AVChapter array.
Definition avformat.h:1387
int metadata_header_padding
Number of bytes to be written as padding in a metadata header.
Definition avformat.h:1843
int64_t output_ts_offset
Output timestamp offset, in microseconds.
Definition avformat.h:1860
void * opaque
User data.
Definition avformat.h:1849
int format_probesize
Maximum number of bytes read from input in order to identify the input format.
Definition avformat.h:1766
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:1694
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:1718
int64_t bit_rate
Total stream bitrate in bit/s, 0 if not available.
Definition avformat.h:1429
int64_t duration_probesize
Maximum number of bytes read from input in order to determine stream durations when using estimate_ti...
Definition avformat.h:1914
char * codec_whitelist
',' separated list of allowed decoders.
Definition avformat.h:1774
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:1535
unsigned int max_index_size
Maximum amount of memory in bytes to use for the index of each stream.
Definition avformat.h:1585
enum AVCodecID video_codec_id
Forced video codec_id.
Definition avformat.h:1494
int debug
Flags to enable debugging.
Definition avformat.h:1565
av_format_control_message control_message_cb
Callback used by devices to communicate with application.
Definition avformat.h:1854
char * format_whitelist
',' separated list of allowed demuxers.
Definition avformat.h:1782
int audio_preload
Audio preload in microseconds.
Definition avformat.h:1686
AVChapter ** chapters
Definition avformat.h:1388
unsigned int nb_stream_groups
Number of elements in AVFormatContext.stream_groups.
Definition avformat.h:1362
void * priv_data
Format private data.
Definition avformat.h:1315
int64_t probesize
Maximum number of bytes read from input in order to determine stream properties.
Definition avformat.h:1474
enum AVCodecID subtitle_codec_id
Forced subtitle codec_id.
Definition avformat.h:1506
AVStream ** streams
A list of all streams in the file.
Definition avformat.h:1355
int64_t duration
Duration of the stream, in AV_TIME_BASE fractional seconds.
Definition avformat.h:1422
int max_ts_probe
Maximum number of packets to read while waiting for the first timestamp.
Definition avformat.h:1615
int64_t skip_initial_bytes
Skip initial bytes when opening stream.
Definition avformat.h:1725
const struct AVCodec * subtitle_codec
Forced subtitle codec.
Definition avformat.h:1828
char * protocol_whitelist
',' separated list of allowed protocols.
Definition avformat.h:1789
char * protocol_blacklist
',' separated list of disallowed protocols.
Definition avformat.h:1796
unsigned int max_picture_buffer
Maximum amount of memory in bytes to use for buffering frames obtained from realtime capture devices.
Definition avformat.h:1591
int max_chunk_duration
Max chunk time in microseconds.
Definition avformat.h:1623
const struct AVCodec * video_codec
Forced video codec.
Definition avformat.h:1812
int skip_estimate_duration_from_pts
Skip duration calcuation in estimate_timings_from_pts.
Definition avformat.h:1703
int error_recognition
Error recognition; higher values will detect more errors but may misdetect some more or less valid pa...
Definition avformat.h:1549
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:1890
int max_probe_packets
Maximum number of packets that can be probed.
Definition avformat.h:1638
unsigned int correct_ts_overflow
Correct single timestamp overflows.
Definition avformat.h:1732
uint8_t * dump_separator
dump format separator.
Definition avformat.h:1868
This structure describes decoded (raw) audio or video data.
Definition frame.h:389
Information on how to combine one or more audio streams, as defined in section 3.6 of IAMF.
Definition iamf.h:356
Information on how to render and mix one or more AVIAMFAudioElement to generate the final audio outpu...
Definition iamf.h:609
Bytestream IO Context.
Definition avio.h:160
Callback for checking whether to abort blocking functions.
Definition avio.h:59
int64_t pos
Definition avformat.h:603
int min_distance
Minimum distance between this and the previous keyframe, used to avoid unneeded searching.
Definition avformat.h:614
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition avformat.h:604
int flags
Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS, AVFMT_NOTIMESTAMPS,...
Definition avformat.h:567
const char * long_name
Descriptive name for the format, meant to be more human-readable than name.
Definition avformat.h:560
const char * name
A comma separated list of short names for the format.
Definition avformat.h:553
const struct AVCodecTag *const * codec_tag
Definition avformat.h:576
const char * mime_type
Comma-separated list of mime types.
Definition avformat.h:585
const char * extensions
If extensions are defined, then no probe is done.
Definition avformat.h:574
const AVClass * priv_class
AVClass for the private context.
Definition avformat.h:578
const char * extensions
comma-separated filename extensions
Definition avformat.h:518
enum AVCodecID video_codec
default video codec
Definition avformat.h:521
enum AVCodecID audio_codec
default audio codec
Definition avformat.h:520
const char * long_name
Descriptive name for the format, meant to be more human-readable than name.
Definition avformat.h:516
int flags
can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS,...
Definition avformat.h:529
const char * name
Definition avformat.h:510
const struct AVCodecTag *const * codec_tag
List of supported codec_id-codec_tag pairs, ordered by "better choice first".
Definition avformat.h:535
const char * mime_type
Definition avformat.h:517
enum AVCodecID subtitle_codec
default subtitle codec
Definition avformat.h:522
const AVClass * priv_class
AVClass for the private context.
Definition avformat.h:538
This structure stores auxiliary information for decoding, presenting, or otherwise processing the cod...
Definition packet.h:390
This structure stores compressed data.
Definition packet.h:516
This structure contains the data a format has to probe a file.
Definition avformat.h:451
const char * filename
Definition avformat.h:452
const char * mime_type
mime_type, when known.
Definition avformat.h:455
int buf_size
Size of buf except extra allocated bytes.
Definition avformat.h:454
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition avformat.h:453
New fields can be added to the end with minor version bumps.
Definition avformat.h:1211
int pmt_pid
Definition avformat.h:1220
unsigned int nb_stream_indexes
Definition avformat.h:1216
int64_t start_time
Definition avformat.h:1231
int program_num
Definition avformat.h:1219
int64_t end_time
Definition avformat.h:1232
unsigned int * stream_index
Definition avformat.h:1215
int pcr_pid
Definition avformat.h:1221
int64_t pts_wrap_reference
reference dts for wrap detection
Definition avformat.h:1234
enum AVDiscard discard
selects which program to discard and which to feed to the caller
Definition avformat.h:1214
int pts_wrap_behavior
behavior on wrap detection
Definition avformat.h:1235
int pmt_version
Definition avformat.h:1222
AVDictionary * metadata
Definition avformat.h:1217
Rational number (pair of numerator and denominator).
Definition rational.h:58
AVStreamGroupLCEVC is meant to define the relation between video streams and a data stream containing...
Definition avformat.h:1093
const AVClass * av_class
Definition avformat.h:1094
int height
Height of the final image for presentation.
Definition avformat.h:1107
unsigned int lcevc_index
Index of the LCEVC data stream in AVStreamGroup.
Definition avformat.h:1099
int width
Width of the final stream for presentation.
Definition avformat.h:1103
AVStreamGroupTileGrid holds information on how to combine several independent images on a single canv...
Definition avformat.h:987
struct AVStreamGroupTileGrid::@3 * offsets
An nb_tiles sized array of offsets in pixels from the topleft edge of the canvas, indicating where ea...
int width
Width of the final image for presentation.
Definition avformat.h:1072
int height
Height of the final image for presentation.
Definition avformat.h:1082
int coded_width
Width of the canvas.
Definition avformat.h:1002
unsigned int nb_tiles
Amount of tiles in the grid.
Definition avformat.h:995
uint8_t background[4]
The pixel value per channel in RGBA format used if no pixel of any tile is located at a particular pi...
Definition avformat.h:1046
int horizontal_offset
Offset in pixels from the left edge of the canvas where the actual image meant for presentation start...
Definition avformat.h:1054
const AVClass * av_class
Definition avformat.h:988
int horizontal
Offset in pixels from the left edge of the canvas where the tile should be placed.
Definition avformat.h:1031
unsigned int idx
Index of the stream in the group this tile references.
Definition avformat.h:1026
int vertical_offset
Offset in pixels from the top edge of the canvas where the actual image meant for presentation starts...
Definition avformat.h:1061
int coded_height
Width of the canvas.
Definition avformat.h:1008
int vertical
Offset in pixels from the top edge of the canvas where the tile should be placed.
Definition avformat.h:1036
enum AVStreamGroupParamsType type
Group type.
Definition avformat.h:1148
struct AVStreamGroupLCEVC * lcevc
Definition avformat.h:1157
struct AVIAMFMixPresentation * iamf_mix_presentation
Definition avformat.h:1155
union AVStreamGroup::@4 params
Group type-specific parameters.
struct AVStreamGroupTileGrid * tile_grid
Definition avformat.h:1156
void * priv_data
Definition avformat.h:1127
unsigned int nb_streams
Number of elements in AVStreamGroup.streams.
Definition avformat.h:1175
AVDictionary * metadata
Metadata that applies to the whole group.
Definition avformat.h:1168
unsigned int index
Group index in AVFormatContext.
Definition avformat.h:1132
struct AVIAMFAudioElement * iamf_audio_element
Definition avformat.h:1154
int disposition
Stream group disposition - a combination of AV_DISPOSITION_* flags.
Definition avformat.h:1198
int64_t id
Group type-specific group ID.
Definition avformat.h:1140
AVStream ** streams
A list of streams in the group.
Definition avformat.h:1188
const AVClass * av_class
A class for AVOptions.
Definition avformat.h:1125
Stream structure.
Definition avformat.h:748
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition avformat.h:771
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition avformat.h:826
int64_t nb_frames
number of frames in this stream if known or 0
Definition avformat.h:809
const AVClass * av_class
A class for AVOptions.
Definition avformat.h:752
enum AVDiscard discard
Selects which packets can be discarded at will and do not need to be demuxed.
Definition avformat.h:819
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition avformat.h:807
AVDictionary * metadata
Definition avformat.h:828
void * priv_data
Definition avformat.h:773
int id
Format-specific stream ID.
Definition avformat.h:760
int index
stream index in AVFormatContext
Definition avformat.h:754
int pts_wrap_bits
Number of bits in timestamps.
Definition avformat.h:923
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition avformat.h:797
AVPacket attached_pic
For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet will contain the attached pictu...
Definition avformat.h:846
AVRational avg_frame_rate
Average framerate.
Definition avformat.h:837
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition avformat.h:787
int event_flags
Flags indicating events happening on the stream, a combination of AVSTREAM_EVENT_FLAG_*.
Definition avformat.h:891
AVRational r_frame_rate
Real base framerate of the stream.
Definition avformat.h:914
int disposition
Stream disposition - a combination of AV_DISPOSITION_* flags.
Definition avformat.h:817
static AVStream * ost