FFmpeg 7.0
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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/**
718 * @return The AV_DISPOSITION_* flag corresponding to disp or a negative error
719 * code if disp does not correspond to a known stream disposition.
720 */
721int av_disposition_from_string(const char *disp);
722
723/**
724 * @param disposition a combination of AV_DISPOSITION_* values
725 * @return The string description corresponding to the lowest set bit in
726 * disposition. NULL when the lowest set bit does not correspond
727 * to a known disposition or when disposition is 0.
728 */
729const char *av_disposition_to_string(int disposition);
730
731/**
732 * Options for behavior on timestamp wrap detection.
733 */
734#define AV_PTS_WRAP_IGNORE 0 ///< ignore the wrap
735#define AV_PTS_WRAP_ADD_OFFSET 1 ///< add the format specific offset on wrap detection
736#define AV_PTS_WRAP_SUB_OFFSET -1 ///< subtract the format specific offset on wrap detection
737
738/**
739 * Stream structure.
740 * New fields can be added to the end with minor version bumps.
741 * Removal, reordering and changes to existing fields require a major
742 * version bump.
743 * sizeof(AVStream) must not be used outside libav*.
744 */
745typedef struct AVStream {
746 /**
747 * A class for @ref avoptions. Set on stream creation.
748 */
750
751 int index; /**< stream index in AVFormatContext */
752 /**
753 * Format-specific stream ID.
754 * decoding: set by libavformat
755 * encoding: set by the user, replaced by libavformat if left unset
756 */
757 int id;
758
759 /**
760 * Codec parameters associated with this stream. Allocated and freed by
761 * libavformat in avformat_new_stream() and avformat_free_context()
762 * respectively.
763 *
764 * - demuxing: filled by libavformat on stream creation or in
765 * avformat_find_stream_info()
766 * - muxing: filled by the caller before avformat_write_header()
767 */
769
770 void *priv_data;
771
772 /**
773 * This is the fundamental unit of time (in seconds) in terms
774 * of which frame timestamps are represented.
775 *
776 * decoding: set by libavformat
777 * encoding: May be set by the caller before avformat_write_header() to
778 * provide a hint to the muxer about the desired timebase. In
779 * avformat_write_header(), the muxer will overwrite this field
780 * with the timebase that will actually be used for the timestamps
781 * written into the file (which may or may not be related to the
782 * user-provided one, depending on the format).
783 */
785
786 /**
787 * Decoding: pts of the first frame of the stream in presentation order, in stream time base.
788 * Only set this if you are absolutely 100% sure that the value you set
789 * it to really is the pts of the first frame.
790 * This may be undefined (AV_NOPTS_VALUE).
791 * @note The ASF header does NOT contain a correct start_time the ASF
792 * demuxer must NOT set this.
793 */
794 int64_t start_time;
795
796 /**
797 * Decoding: duration of the stream, in stream time base.
798 * If a source file does not specify a duration, but does specify
799 * a bitrate, this value will be estimated from bitrate and file size.
800 *
801 * Encoding: May be set by the caller before avformat_write_header() to
802 * provide a hint to the muxer about the estimated duration.
803 */
804 int64_t duration;
805
806 int64_t nb_frames; ///< number of frames in this stream if known or 0
807
808 /**
809 * Stream disposition - a combination of AV_DISPOSITION_* flags.
810 * - demuxing: set by libavformat when creating the stream or in
811 * avformat_find_stream_info().
812 * - muxing: may be set by the caller before avformat_write_header().
813 */
815
816 enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
817
818 /**
819 * sample aspect ratio (0 if unknown)
820 * - encoding: Set by user.
821 * - decoding: Set by libavformat.
822 */
824
826
827 /**
828 * Average framerate
829 *
830 * - demuxing: May be set by libavformat when creating the stream or in
831 * avformat_find_stream_info().
832 * - muxing: May be set by the caller before avformat_write_header().
833 */
835
836 /**
837 * For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet
838 * will contain the attached picture.
839 *
840 * decoding: set by libavformat, must not be modified by the caller.
841 * encoding: unused
842 */
844
845#if FF_API_AVSTREAM_SIDE_DATA
846 /**
847 * An array of side data that applies to the whole stream (i.e. the
848 * container does not allow it to change between packets).
849 *
850 * There may be no overlap between the side data in this array and side data
851 * in the packets. I.e. a given side data is either exported by the muxer
852 * (demuxing) / set by the caller (muxing) in this array, then it never
853 * appears in the packets, or the side data is exported / sent through
854 * the packets (always in the first packet where the value becomes known or
855 * changes), then it does not appear in this array.
856 *
857 * - demuxing: Set by libavformat when the stream is created.
858 * - muxing: May be set by the caller before avformat_write_header().
859 *
860 * Freed by libavformat in avformat_free_context().
861 *
862 * @deprecated use AVStream's @ref AVCodecParameters.coded_side_data
863 * "codecpar side data".
864 */
866 AVPacketSideData *side_data;
867 /**
868 * The number of elements in the AVStream.side_data array.
869 *
870 * @deprecated use AVStream's @ref AVCodecParameters.nb_coded_side_data
871 * "codecpar side data".
872 */
874 int nb_side_data;
875#endif
876
877 /**
878 * Flags indicating events happening on the stream, a combination of
879 * AVSTREAM_EVENT_FLAG_*.
880 *
881 * - demuxing: may be set by the demuxer in avformat_open_input(),
882 * avformat_find_stream_info() and av_read_frame(). Flags must be cleared
883 * by the user once the event has been handled.
884 * - muxing: may be set by the user after avformat_write_header(). to
885 * indicate a user-triggered event. The muxer will clear the flags for
886 * events it has handled in av_[interleaved]_write_frame().
887 */
888 int event_flags;
889/**
890 * - demuxing: the demuxer read new metadata from the file and updated
891 * AVStream.metadata accordingly
892 * - muxing: the user updated AVStream.metadata and wishes the muxer to write
893 * it into the file
894 */
895#define AVSTREAM_EVENT_FLAG_METADATA_UPDATED 0x0001
896/**
897 * - demuxing: new packets for this stream were read from the file. This
898 * event is informational only and does not guarantee that new packets
899 * for this stream will necessarily be returned from av_read_frame().
900 */
901#define AVSTREAM_EVENT_FLAG_NEW_PACKETS (1 << 1)
902
903 /**
904 * Real base framerate of the stream.
905 * This is the lowest framerate with which all timestamps can be
906 * represented accurately (it is the least common multiple of all
907 * framerates in the stream). Note, this value is just a guess!
908 * For example, if the time base is 1/90000 and all frames have either
909 * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
910 */
912
913 /**
914 * Number of bits in timestamps. Used for wrapping control.
915 *
916 * - demuxing: set by libavformat
917 * - muxing: set by libavformat
919 */
920 int pts_wrap_bits;
921} AVStream;
922
923/**
924 * AVStreamGroupTileGrid holds information on how to combine several
925 * independent images on a single canvas for presentation.
926 *
927 * The output should be a @ref AVStreamGroupTileGrid.background "background"
928 * colored @ref AVStreamGroupTileGrid.coded_width "coded_width" x
929 * @ref AVStreamGroupTileGrid.coded_height "coded_height" canvas where a
930 * @ref AVStreamGroupTileGrid.nb_tiles "nb_tiles" amount of tiles are placed in
931 * the order they appear in the @ref AVStreamGroupTileGrid.offsets "offsets"
932 * array, at the exact offset described for them. In particular, if two or more
933 * tiles overlap, the image with higher index in the
934 * @ref AVStreamGroupTileGrid.offsets "offsets" array takes priority.
935 * Note that a single image may be used multiple times, i.e. multiple entries
936 * in @ref AVStreamGroupTileGrid.offsets "offsets" may have the same value of
937 * idx.
938 *
939 * The following is an example of a simple grid with 3 rows and 4 columns:
940 *
941 * +---+---+---+---+
942 * | 0 | 1 | 2 | 3 |
943 * +---+---+---+---+
944 * | 4 | 5 | 6 | 7 |
945 * +---+---+---+---+
946 * | 8 | 9 |10 |11 |
947 * +---+---+---+---+
948 *
949 * Assuming all tiles have a dimension of 512x512, the
950 * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
951 * the first @ref AVStreamGroup.streams "stream" in the group is "0,0", the
952 * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
953 * the second @ref AVStreamGroup.streams "stream" in the group is "512,0", the
954 * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
955 * the fifth @ref AVStreamGroup.streams "stream" in the group is "0,512", the
956 * @ref AVStreamGroupTileGrid.offsets "offset", of the topleft pixel of
957 * the sixth @ref AVStreamGroup.streams "stream" in the group is "512,512",
958 * etc.
959 *
960 * The following is an example of a canvas with overlaping tiles:
961 *
962 * +-----------+
963 * | %%%%% |
964 * |***%%3%%@@@|
965 * |**0%%%%%2@@|
966 * |***##1@@@@@|
967 * | ##### |
968 * +-----------+
969 *
970 * Assuming a canvas with size 1024x1024 and all tiles with a dimension of
971 * 512x512, a possible @ref AVStreamGroupTileGrid.offsets "offset" for the
972 * topleft pixel of the first @ref AVStreamGroup.streams "stream" in the group
973 * would be 0x256, the @ref AVStreamGroupTileGrid.offsets "offset" for the
974 * topleft pixel of the second @ref AVStreamGroup.streams "stream" in the group
975 * would be 256x512, the @ref AVStreamGroupTileGrid.offsets "offset" for the
976 * topleft pixel of the third @ref AVStreamGroup.streams "stream" in the group
977 * would be 512x256, and the @ref AVStreamGroupTileGrid.offsets "offset" for
978 * the topleft pixel of the fourth @ref AVStreamGroup.streams "stream" in the
979 * group would be 256x0.
980 *
981 * sizeof(AVStreamGroupTileGrid) is not a part of the ABI and may only be
982 * allocated by avformat_stream_group_create().
983 */
984typedef struct AVStreamGroupTileGrid {
985 const AVClass *av_class;
986
987 /**
988 * Amount of tiles in the grid.
989 *
990 * Must be > 0.
991 */
992 unsigned int nb_tiles;
993
994 /**
995 * Width of the canvas.
996 *
997 * Must be > 0.
998 */
999 int coded_width;
1000 /**
1001 * Width of the canvas.
1002 *
1003 * Must be > 0.
1004 */
1005 int coded_height;
1006
1007 /**
1008 * An @ref nb_tiles sized array of offsets in pixels from the topleft edge
1009 * of the canvas, indicating where each stream should be placed.
1010 * It must be allocated with the av_malloc() family of functions.
1011 *
1012 * - demuxing: set by libavformat, must not be modified by the caller.
1013 * - muxing: set by the caller before avformat_write_header().
1014 *
1015 * Freed by libavformat in avformat_free_context().
1016 */
1017 struct {
1018 /**
1019 * Index of the stream in the group this tile references.
1020 *
1021 * Must be < @ref AVStreamGroup.nb_streams "nb_streams".
1022 */
1023 unsigned int idx;
1024 /**
1025 * Offset in pixels from the left edge of the canvas where the tile
1026 * should be placed.
1027 */
1028 int horizontal;
1029 /**
1030 * Offset in pixels from the top edge of the canvas where the tile
1031 * should be placed.
1033 int vertical;
1034 } *offsets;
1035
1036 /**
1037 * The pixel value per channel in RGBA format used if no pixel of any tile
1038 * is located at a particular pixel location.
1039 *
1040 * @see av_image_fill_color().
1041 * @see av_parse_color().
1042 */
1043 uint8_t background[4];
1044
1045 /**
1046 * Offset in pixels from the left edge of the canvas where the actual image
1047 * meant for presentation starts.
1048 *
1049 * This field must be >= 0 and < @ref coded_width.
1050 */
1052 /**
1053 * Offset in pixels from the top edge of the canvas where the actual image
1054 * meant for presentation starts.
1055 *
1056 * This field must be >= 0 and < @ref coded_height.
1057 */
1058 int vertical_offset;
1059
1060 /**
1061 * Width of the final image for presentation.
1062 *
1063 * Must be > 0 and <= (@ref coded_width - @ref horizontal_offset).
1064 * When it's not equal to (@ref coded_width - @ref horizontal_offset), the
1065 * result of (@ref coded_width - width - @ref horizontal_offset) is the
1066 * amount amount of pixels to be cropped from the right edge of the
1067 * final image before presentation.
1068 */
1069 int width;
1070 /**
1071 * Height of the final image for presentation.
1072 *
1073 * Must be > 0 and <= (@ref coded_height - @ref vertical_offset).
1074 * When it's not equal to (@ref coded_height - @ref vertical_offset), the
1075 * result of (@ref coded_height - height - @ref vertical_offset) is the
1076 * amount amount of pixels to be cropped from the bottom edge of the
1077 * final image before presentation.
1078 */
1079 int height;
1087};
1088
1089struct AVIAMFAudioElement;
1091
1092typedef struct AVStreamGroup {
1093 /**
1094 * A class for @ref avoptions. Set by avformat_stream_group_create().
1095 */
1097
1098 void *priv_data;
1099
1100 /**
1101 * Group index in AVFormatContext.
1102 */
1103 unsigned int index;
1104
1105 /**
1106 * Group type-specific group ID.
1107 *
1108 * decoding: set by libavformat
1109 * encoding: may set by the user
1110 */
1111 int64_t id;
1112
1113 /**
1114 * Group type
1115 *
1116 * decoding: set by libavformat on group creation
1117 * encoding: set by avformat_stream_group_create()
1118 */
1120
1121 /**
1122 * Group type-specific parameters
1124 union {
1128 } params;
1129
1130 /**
1131 * Metadata that applies to the whole group.
1132 *
1133 * - demuxing: set by libavformat on group creation
1134 * - muxing: may be set by the caller before avformat_write_header()
1135 *
1136 * Freed by libavformat in avformat_free_context().
1137 */
1139
1140 /**
1141 * Number of elements in AVStreamGroup.streams.
1142 *
1143 * Set by avformat_stream_group_add_stream() must not be modified by any other code.
1144 */
1145 unsigned int nb_streams;
1146
1147 /**
1148 * A list of streams in the group. New entries are created with
1149 * avformat_stream_group_add_stream().
1150 *
1151 * - demuxing: entries are created by libavformat on group creation.
1152 * If AVFMTCTX_NOHEADER is set in ctx_flags, then new entries may also
1153 * appear in av_read_frame().
1154 * - muxing: entries are created by the user before avformat_write_header().
1155 *
1156 * Freed by libavformat in avformat_free_context().
1157 */
1158 AVStream **streams;
1159
1160 /**
1161 * Stream group disposition - a combination of AV_DISPOSITION_* flags.
1162 * This field currently applies to all defined AVStreamGroupParamsType.
1163 *
1164 * - demuxing: set by libavformat when creating the group or in
1165 * avformat_find_stream_info().
1166 * - muxing: may be set by the caller before avformat_write_header().
1167 */
1168 int disposition;
1170
1172
1173#define AV_PROGRAM_RUNNING 1
1174
1175/**
1176 * New fields can be added to the end with minor version bumps.
1177 * Removal, reordering and changes to existing fields require a major
1178 * version bump.
1179 * sizeof(AVProgram) must not be used outside libav*.
1181typedef struct AVProgram {
1182 int id;
1184 enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
1185 unsigned int *stream_index;
1186 unsigned int nb_stream_indexes;
1191 int pcr_pid;
1192 int pmt_version;
1193
1194 /*****************************************************************
1195 * All fields below this line are not part of the public API. They
1196 * may not be used outside of libavformat and can be changed and
1197 * removed at will.
1198 * New public fields should be added right above.
1199 *****************************************************************
1201 int64_t start_time;
1202 int64_t end_time;
1204 int64_t pts_wrap_reference; ///< reference dts for wrap detection
1205 int pts_wrap_behavior; ///< behavior on wrap detection
1206} AVProgram;
1208#define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
1209 (streams are added dynamically) */
1210#define AVFMTCTX_UNSEEKABLE 0x0002 /**< signal that the stream is definitely
1211 not seekable, and attempts to call the
1212 seek function will fail. For some
1213 network protocols (e.g. HLS), this can
1214 change dynamically at runtime. */
1216typedef struct AVChapter {
1217 int64_t id; ///< unique ID to identify the chapter
1218 AVRational time_base; ///< time base in which the start/end timestamps are specified
1219 int64_t start, end; ///< chapter start/end time in time_base units
1221} AVChapter;
1222
1223
1224/**
1225 * Callback used by devices to communicate with application.
1226 */
1227typedef int (*av_format_control_message)(struct AVFormatContext *s, int type,
1228 void *data, size_t data_size);
1229
1230typedef int (*AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags,
1231 const AVIOInterruptCB *int_cb, AVDictionary **options);
1232
1233/**
1234 * The duration of a video can be estimated through various ways, and this enum can be used
1235 * to know how the duration was estimated.
1238 AVFMT_DURATION_FROM_PTS, ///< Duration accurately estimated from PTSes
1239 AVFMT_DURATION_FROM_STREAM, ///< Duration estimated from a stream with a known duration
1240 AVFMT_DURATION_FROM_BITRATE ///< Duration estimated from bitrate (less accurate)
1241};
1242
1243/**
1244 * Format I/O context.
1245 * New fields can be added to the end with minor version bumps.
1246 * Removal, reordering and changes to existing fields require a major
1247 * version bump.
1248 * sizeof(AVFormatContext) must not be used outside libav*, use
1249 * avformat_alloc_context() to create an AVFormatContext.
1250 *
1251 * Fields can be accessed through AVOptions (av_opt*),
1252 * the name string used matches the associated command line parameter name and
1253 * can be found in libavformat/options_table.h.
1254 * The AVOption/command line parameter names differ in some cases from the C
1255 * structure field names for historic reasons or brevity.
1256 */
1257typedef struct AVFormatContext {
1258 /**
1259 * A class for logging and @ref avoptions. Set by avformat_alloc_context().
1260 * Exports (de)muxer private options if they exist.
1261 */
1262 const AVClass *av_class;
1263
1264 /**
1265 * The input container format.
1266 *
1267 * Demuxing only, set by avformat_open_input().
1268 */
1269 const struct AVInputFormat *iformat;
1270
1271 /**
1272 * The output container format.
1273 *
1274 * Muxing only, must be set by the caller before avformat_write_header().
1275 */
1276 const struct AVOutputFormat *oformat;
1277
1278 /**
1279 * Format private data. This is an AVOptions-enabled struct
1280 * if and only if iformat/oformat.priv_class is not NULL.
1281 *
1282 * - muxing: set by avformat_write_header()
1283 * - demuxing: set by avformat_open_input()
1284 */
1285 void *priv_data;
1286
1287 /**
1288 * I/O context.
1289 *
1290 * - demuxing: either set by the user before avformat_open_input() (then
1291 * the user must close it manually) or set by avformat_open_input().
1292 * - muxing: set by the user before avformat_write_header(). The caller must
1293 * take care of closing / freeing the IO context.
1294 *
1295 * Do NOT set this field if AVFMT_NOFILE flag is set in
1296 * iformat/oformat.flags. In such a case, the (de)muxer will handle
1297 * I/O in some other way and this field will be NULL.
1298 */
1299 AVIOContext *pb;
1300
1301 /* stream info */
1302 /**
1303 * Flags signalling stream properties. A combination of AVFMTCTX_*.
1304 * Set by libavformat.
1305 */
1306 int ctx_flags;
1307
1308 /**
1309 * Number of elements in AVFormatContext.streams.
1310 *
1311 * Set by avformat_new_stream(), must not be modified by any other code.
1312 */
1313 unsigned int nb_streams;
1314 /**
1315 * A list of all streams in the file. New streams are created with
1316 * avformat_new_stream().
1317 *
1318 * - demuxing: streams are created by libavformat in avformat_open_input().
1319 * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
1320 * appear in av_read_frame().
1321 * - muxing: streams are created by the user before avformat_write_header().
1322 *
1323 * Freed by libavformat in avformat_free_context().
1324 */
1325 AVStream **streams;
1326
1327 /**
1328 * Number of elements in AVFormatContext.stream_groups.
1329 *
1330 * Set by avformat_stream_group_create(), must not be modified by any other code.
1331 */
1332 unsigned int nb_stream_groups;
1333 /**
1334 * A list of all stream groups in the file. New groups are created with
1335 * avformat_stream_group_create(), and filled with avformat_stream_group_add_stream().
1336 *
1337 * - demuxing: groups may be created by libavformat in avformat_open_input().
1338 * If AVFMTCTX_NOHEADER is set in ctx_flags, then new groups may also
1339 * appear in av_read_frame().
1340 * - muxing: groups may be created by the user before avformat_write_header().
1341 *
1342 * Freed by libavformat in avformat_free_context().
1343 */
1345
1346 /**
1347 * Number of chapters in AVChapter array.
1348 * When muxing, chapters are normally written in the file header,
1349 * so nb_chapters should normally be initialized before write_header
1350 * is called. Some muxers (e.g. mov and mkv) can also write chapters
1351 * in the trailer. To write chapters in the trailer, nb_chapters
1352 * must be zero when write_header is called and non-zero when
1353 * write_trailer is called.
1354 * - muxing: set by user
1355 * - demuxing: set by libavformat
1357 unsigned int nb_chapters;
1359
1360 /**
1361 * input or output URL. Unlike the old filename field, this field has no
1362 * length restriction.
1363 *
1364 * - demuxing: set by avformat_open_input(), initialized to an empty
1365 * string if url parameter was NULL in avformat_open_input().
1366 * - muxing: may be set by the caller before calling avformat_write_header()
1367 * (or avformat_init_output() if that is called first) to a string
1368 * which is freeable by av_free(). Set to an empty string if it
1369 * was NULL in avformat_init_output().
1370 *
1371 * Freed by libavformat in avformat_free_context().
1372 */
1373 char *url;
1374
1375 /**
1376 * Position of the first frame of the component, in
1377 * AV_TIME_BASE fractional seconds. NEVER set this value directly:
1378 * It is deduced from the AVStream values.
1379 *
1380 * Demuxing only, set by libavformat.
1381 */
1382 int64_t start_time;
1383
1384 /**
1385 * Duration of the stream, in AV_TIME_BASE fractional
1386 * seconds. Only set this value if you know none of the individual stream
1387 * durations and also do not set any of them. This is deduced from the
1388 * AVStream values if not set.
1389 *
1390 * Demuxing only, set by libavformat.
1391 */
1392 int64_t duration;
1393
1394 /**
1395 * Total stream bitrate in bit/s, 0 if not
1396 * available. Never set it directly if the file_size and the
1397 * duration are known as FFmpeg can compute it automatically.
1398 */
1399 int64_t bit_rate;
1401 unsigned int packet_size;
1402 int max_delay;
1403
1404 /**
1405 * Flags modifying the (de)muxer behaviour. A combination of AVFMT_FLAG_*.
1406 * Set by the user before avformat_open_input() / avformat_write_header().
1409#define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
1410#define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
1411#define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
1412#define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
1413#define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
1414#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
1415#define AVFMT_FLAG_NOBUFFER 0x0040 ///< Do not buffer frames when possible
1416#define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
1417#define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted
1418#define AVFMT_FLAG_FLUSH_PACKETS 0x0200 ///< Flush the AVIOContext every packet.
1419/**
1420 * When muxing, try to avoid writing any random/volatile data to the output.
1421 * This includes any random IDs, real-time timestamps/dates, muxer version, etc.
1422 *
1423 * This flag is mainly intended for testing.
1425#define AVFMT_FLAG_BITEXACT 0x0400
1426#define AVFMT_FLAG_SORT_DTS 0x10000 ///< try to interleave outputted packets by dts (using this flag can slow demuxing down)
1427#define AVFMT_FLAG_FAST_SEEK 0x80000 ///< Enable fast, but inaccurate seeks for some formats
1428#if FF_API_LAVF_SHORTEST
1429#define AVFMT_FLAG_SHORTEST 0x100000 ///< Stop muxing when the shortest stream stops.
1430#endif
1431#define AVFMT_FLAG_AUTO_BSF 0x200000 ///< Add bitstream filters as requested by the muxer
1432
1433 /**
1434 * Maximum number of bytes read from input in order to determine stream
1435 * properties. Used when reading the global header and in
1436 * avformat_find_stream_info().
1437 *
1438 * Demuxing only, set by the caller before avformat_open_input().
1439 *
1440 * @note this is \e not used for determining the \ref AVInputFormat
1441 * "input format"
1442 * @sa format_probesize
1443 */
1444 int64_t probesize;
1445
1446 /**
1447 * Maximum duration (in AV_TIME_BASE units) of the data read
1448 * from input in avformat_find_stream_info().
1449 * Demuxing only, set by the caller before avformat_find_stream_info().
1450 * Can be set to 0 to let avformat choose using a heuristic.
1451 */
1454 const uint8_t *key;
1457 unsigned int nb_programs;
1459
1460 /**
1461 * Forced video codec_id.
1462 * Demuxing: Set by user.
1463 */
1465
1466 /**
1467 * Forced audio codec_id.
1468 * Demuxing: Set by user.
1469 */
1471
1472 /**
1473 * Forced subtitle codec_id.
1474 * Demuxing: Set by user.
1475 */
1477
1478 /**
1479 * Forced Data codec_id.
1480 * Demuxing: Set by user.
1481 */
1483
1484 /**
1485 * Metadata that applies to the whole file.
1486 *
1487 * - demuxing: set by libavformat in avformat_open_input()
1488 * - muxing: may be set by the caller before avformat_write_header()
1489 *
1490 * Freed by libavformat in avformat_free_context().
1491 */
1493
1494 /**
1495 * Start time of the stream in real world time, in microseconds
1496 * since the Unix epoch (00:00 1st January 1970). That is, pts=0 in the
1497 * stream was captured at this real world time.
1498 * - muxing: Set by the caller before avformat_write_header(). If set to
1499 * either 0 or AV_NOPTS_VALUE, then the current wall-time will
1500 * be used.
1501 * - demuxing: Set by libavformat. AV_NOPTS_VALUE if unknown. Note that
1502 * the value may become known after some number of frames
1503 * have been received.
1504 */
1505 int64_t start_time_realtime;
1506
1507 /**
1508 * The number of frames used for determining the framerate in
1509 * avformat_find_stream_info().
1510 * Demuxing only, set by the caller before avformat_find_stream_info().
1511 */
1512 int fps_probe_size;
1513
1514 /**
1515 * Error recognition; higher values will detect more errors but may
1516 * misdetect some more or less valid parts as errors.
1517 * Demuxing only, set by the caller before avformat_open_input().
1518 */
1520
1521 /**
1522 * Custom interrupt callbacks for the I/O layer.
1523 *
1524 * demuxing: set by the user before avformat_open_input().
1525 * muxing: set by the user before avformat_write_header()
1526 * (mainly useful for AVFMT_NOFILE formats). The callback
1527 * should also be passed to avio_open2() if it's used to
1528 * open the file.
1529 */
1531
1532 /**
1533 * Flags to enable debugging.
1535 int debug;
1536#define FF_FDEBUG_TS 0x0001
1537
1538 /**
1539 * The maximum number of streams.
1540 * - encoding: unused
1541 * - decoding: set by user
1542 */
1543 int max_streams;
1544
1545 /**
1546 * Maximum amount of memory in bytes to use for the index of each stream.
1547 * If the index exceeds this size, entries will be discarded as
1548 * needed to maintain a smaller size. This can lead to slower or less
1549 * accurate seeking (depends on demuxer).
1550 * Demuxers for which a full in-memory index is mandatory will ignore
1551 * this.
1552 * - muxing: unused
1553 * - demuxing: set by user
1554 */
1555 unsigned int max_index_size;
1556
1557 /**
1558 * Maximum amount of memory in bytes to use for buffering frames
1559 * obtained from realtime capture devices.
1560 */
1561 unsigned int max_picture_buffer;
1562
1563 /**
1564 * Maximum buffering duration for interleaving.
1565 *
1566 * To ensure all the streams are interleaved correctly,
1567 * av_interleaved_write_frame() will wait until it has at least one packet
1568 * for each stream before actually writing any packets to the output file.
1569 * When some streams are "sparse" (i.e. there are large gaps between
1570 * successive packets), this can result in excessive buffering.
1571 *
1572 * This field specifies the maximum difference between the timestamps of the
1573 * first and the last packet in the muxing queue, above which libavformat
1574 * will output a packet regardless of whether it has queued a packet for all
1575 * the streams.
1576 *
1577 * Muxing only, set by the caller before avformat_write_header().
1578 */
1579 int64_t max_interleave_delta;
1580
1581 /**
1582 * Maximum number of packets to read while waiting for the first timestamp.
1583 * Decoding only.
1584 */
1585 int max_ts_probe;
1586
1587 /**
1588 * Max chunk time in microseconds.
1589 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1590 * - encoding: Set by user
1591 * - decoding: unused
1592 */
1594
1595 /**
1596 * Max chunk size in bytes
1597 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1598 * - encoding: Set by user
1599 * - decoding: unused
1600 */
1601 int max_chunk_size;
1602
1603 /**
1604 * Maximum number of packets that can be probed
1605 * - encoding: unused
1606 * - decoding: set by user
1607 */
1609
1610 /**
1611 * Allow non-standard and experimental extension
1612 * @see AVCodecContext.strict_std_compliance
1613 */
1615
1616 /**
1617 * Flags indicating events happening on the file, a combination of
1618 * AVFMT_EVENT_FLAG_*.
1619 *
1620 * - demuxing: may be set by the demuxer in avformat_open_input(),
1621 * avformat_find_stream_info() and av_read_frame(). Flags must be cleared
1622 * by the user once the event has been handled.
1623 * - muxing: may be set by the user after avformat_write_header() to
1624 * indicate a user-triggered event. The muxer will clear the flags for
1625 * events it has handled in av_[interleaved]_write_frame().
1626 */
1627 int event_flags;
1628/**
1629 * - demuxing: the demuxer read new metadata from the file and updated
1630 * AVFormatContext.metadata accordingly
1631 * - muxing: the user updated AVFormatContext.metadata and wishes the muxer to
1632 * write it into the file
1633 */
1634#define AVFMT_EVENT_FLAG_METADATA_UPDATED 0x0001
1635
1636
1637 /**
1638 * Avoid negative timestamps during muxing.
1639 * Any value of the AVFMT_AVOID_NEG_TS_* constants.
1640 * Note, this works better when using av_interleaved_write_frame().
1641 * - muxing: Set by user
1642 * - demuxing: unused
1645#define AVFMT_AVOID_NEG_TS_AUTO -1 ///< Enabled when required by target format
1646#define AVFMT_AVOID_NEG_TS_DISABLED 0 ///< Do not shift timestamps even when they are negative.
1647#define AVFMT_AVOID_NEG_TS_MAKE_NON_NEGATIVE 1 ///< Shift timestamps so they are non negative
1648#define AVFMT_AVOID_NEG_TS_MAKE_ZERO 2 ///< Shift timestamps so that they start at 0
1649
1650 /**
1651 * Audio preload in microseconds.
1652 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1653 * - encoding: Set by user
1654 * - decoding: unused
1655 */
1656 int audio_preload;
1657
1658 /**
1659 * forces the use of wallclock timestamps as pts/dts of packets
1660 * This has undefined results in the presence of B frames.
1661 * - encoding: unused
1662 * - decoding: Set by user
1663 */
1665
1666 /**
1667 * Skip duration calcuation in estimate_timings_from_pts.
1668 * - encoding: unused
1669 * - decoding: set by user
1670 */
1672
1673 /**
1674 * avio flags, used to force AVIO_FLAG_DIRECT.
1675 * - encoding: unused
1676 * - decoding: Set by user
1677 */
1678 int avio_flags;
1679
1680 /**
1681 * The duration field can be estimated through various ways, and this field can be used
1682 * to know how the duration was estimated.
1683 * - encoding: unused
1684 * - decoding: Read by user
1685 */
1687
1688 /**
1689 * Skip initial bytes when opening stream
1690 * - encoding: unused
1691 * - decoding: Set by user
1692 */
1693 int64_t skip_initial_bytes;
1694
1695 /**
1696 * Correct single timestamp overflows
1697 * - encoding: unused
1698 * - decoding: Set by user
1699 */
1700 unsigned int correct_ts_overflow;
1701
1702 /**
1703 * Force seeking to any (also non key) frames.
1704 * - encoding: unused
1705 * - decoding: Set by user
1706 */
1707 int seek2any;
1708
1709 /**
1710 * Flush the I/O context after each packet.
1711 * - encoding: Set by user
1712 * - decoding: unused
1713 */
1714 int flush_packets;
1715
1716 /**
1717 * format probing score.
1718 * The maximal score is AVPROBE_SCORE_MAX, its set when the demuxer probes
1719 * the format.
1720 * - encoding: unused
1721 * - decoding: set by avformat, read by user
1722 */
1723 int probe_score;
1724
1725 /**
1726 * Maximum number of bytes read from input in order to identify the
1727 * \ref AVInputFormat "input format". Only used when the format is not set
1728 * explicitly by the caller.
1729 *
1730 * Demuxing only, set by the caller before avformat_open_input().
1731 *
1732 * @sa probesize
1733 */
1734 int format_probesize;
1735
1736 /**
1737 * ',' separated list of allowed decoders.
1738 * If NULL then all are allowed
1739 * - encoding: unused
1740 * - decoding: set by user
1741 */
1742 char *codec_whitelist;
1743
1744 /**
1745 * ',' separated list of allowed demuxers.
1746 * If NULL then all are allowed
1747 * - encoding: unused
1748 * - decoding: set by user
1749 */
1750 char *format_whitelist;
1751
1752 /**
1753 * ',' separated list of allowed protocols.
1754 * - encoding: unused
1755 * - decoding: set by user
1756 */
1757 char *protocol_whitelist;
1758
1759 /**
1760 * ',' separated list of disallowed protocols.
1761 * - encoding: unused
1762 * - decoding: set by user
1763 */
1764 char *protocol_blacklist;
1765
1766 /**
1767 * IO repositioned flag.
1768 * This is set by avformat when the underlaying IO context read pointer
1769 * is repositioned, for example when doing byte based seeking.
1770 * Demuxers can use the flag to detect such changes.
1771 */
1772 int io_repositioned;
1773
1774 /**
1775 * Forced video codec.
1776 * This allows forcing a specific decoder, even when there are multiple with
1777 * the same codec_id.
1778 * Demuxing: Set by user
1779 */
1780 const struct AVCodec *video_codec;
1781
1782 /**
1783 * Forced audio codec.
1784 * This allows forcing a specific decoder, even when there are multiple with
1785 * the same codec_id.
1786 * Demuxing: Set by user
1787 */
1788 const struct AVCodec *audio_codec;
1789
1790 /**
1791 * Forced subtitle codec.
1792 * This allows forcing a specific decoder, even when there are multiple with
1793 * the same codec_id.
1794 * Demuxing: Set by user
1795 */
1796 const struct AVCodec *subtitle_codec;
1797
1798 /**
1799 * Forced data codec.
1800 * This allows forcing a specific decoder, even when there are multiple with
1801 * the same codec_id.
1802 * Demuxing: Set by user
1803 */
1804 const struct AVCodec *data_codec;
1805
1806 /**
1807 * Number of bytes to be written as padding in a metadata header.
1808 * Demuxing: Unused.
1809 * Muxing: Set by user.
1810 */
1812
1813 /**
1814 * User data.
1815 * This is a place for some private data of the user.
1816 */
1817 void *opaque;
1818
1819 /**
1820 * Callback used by devices to communicate with application.
1821 */
1823
1824 /**
1825 * Output timestamp offset, in microseconds.
1826 * Muxing: set by user
1827 */
1828 int64_t output_ts_offset;
1829
1830 /**
1831 * dump format separator.
1832 * can be ", " or "\n " or anything else
1833 * - muxing: Set by user.
1834 * - demuxing: Set by user.
1835 */
1836 uint8_t *dump_separator;
1837
1838 /**
1839 * A callback for opening new IO streams.
1840 *
1841 * Whenever a muxer or a demuxer needs to open an IO stream (typically from
1842 * avformat_open_input() for demuxers, but for certain formats can happen at
1843 * other times as well), it will call this callback to obtain an IO context.
1844 *
1845 * @param s the format context
1846 * @param pb on success, the newly opened IO context should be returned here
1847 * @param url the url to open
1848 * @param flags a combination of AVIO_FLAG_*
1849 * @param options a dictionary of additional options, with the same
1850 * semantics as in avio_open2()
1851 * @return 0 on success, a negative AVERROR code on failure
1852 *
1853 * @note Certain muxers and demuxers do nesting, i.e. they open one or more
1854 * additional internal format contexts. Thus the AVFormatContext pointer
1855 * passed to this callback may be different from the one facing the caller.
1856 * It will, however, have the same 'opaque' field.
1857 */
1858 int (*io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url,
1859 int flags, AVDictionary **options);
1860
1861 /**
1862 * A callback for closing the streams opened with AVFormatContext.io_open().
1863 *
1864 * Using this is preferred over io_close, because this can return an error.
1865 * Therefore this callback is used instead of io_close by the generic
1866 * libavformat code if io_close is NULL or the default.
1867 *
1868 * @param s the format context
1869 * @param pb IO context to be closed and freed
1870 * @return 0 on success, a negative AVERROR code on failure
1871 */
1872 int (*io_close2)(struct AVFormatContext *s, AVIOContext *pb);
1874
1875/**
1876 * This function will cause global side data to be injected in the next packet
1877 * of each stream as well as after any subsequent seek.
1878 *
1879 * @note global side data is always available in every AVStream's
1880 * @ref AVCodecParameters.coded_side_data "codecpar side data" array, and
1881 * in a @ref AVCodecContext.coded_side_data "decoder's side data" array if
1882 * initialized with said stream's codecpar.
1883 * @see av_packet_side_data_get()
1884 */
1886
1887#if FF_API_GET_DUR_ESTIMATE_METHOD
1888/**
1889 * Returns the method used to set ctx->duration.
1890 *
1891 * @return AVFMT_DURATION_FROM_PTS, AVFMT_DURATION_FROM_STREAM, or AVFMT_DURATION_FROM_BITRATE.
1892 * @deprecated duration_estimation_method is public and can be read directly.
1893 */
1895enum AVDurationEstimationMethod av_fmt_ctx_get_duration_estimation_method(const AVFormatContext* ctx);
1896#endif
1897
1898/**
1899 * @defgroup lavf_core Core functions
1900 * @ingroup libavf
1901 *
1902 * Functions for querying libavformat capabilities, allocating core structures,
1903 * etc.
1904 * @{
1905 */
1906
1907/**
1908 * Return the LIBAVFORMAT_VERSION_INT constant.
1909 */
1910unsigned avformat_version(void);
1911
1912/**
1913 * Return the libavformat build-time configuration.
1914 */
1915const char *avformat_configuration(void);
1916
1917/**
1918 * Return the libavformat license.
1919 */
1920const char *avformat_license(void);
1921
1922/**
1923 * Do global initialization of network libraries. This is optional,
1924 * and not recommended anymore.
1925 *
1926 * This functions only exists to work around thread-safety issues
1927 * with older GnuTLS or OpenSSL libraries. If libavformat is linked
1928 * to newer versions of those libraries, or if you do not use them,
1929 * calling this function is unnecessary. Otherwise, you need to call
1930 * this function before any other threads using them are started.
1931 *
1932 * This function will be deprecated once support for older GnuTLS and
1933 * OpenSSL libraries is removed, and this function has no purpose
1934 * anymore.
1935 */
1936int avformat_network_init(void);
1937
1938/**
1939 * Undo the initialization done by avformat_network_init. Call it only
1940 * once for each time you called avformat_network_init.
1941 */
1942int avformat_network_deinit(void);
1943
1944/**
1945 * Iterate over all registered muxers.
1946 *
1947 * @param opaque a pointer where libavformat will store the iteration state. Must
1948 * point to NULL to start the iteration.
1949 *
1950 * @return the next registered muxer or NULL when the iteration is
1951 * finished
1952 */
1954
1955/**
1956 * Iterate over all registered demuxers.
1957 *
1958 * @param opaque a pointer where libavformat will store the iteration state.
1959 * Must point to NULL to start the iteration.
1960 *
1961 * @return the next registered demuxer or NULL when the iteration is
1962 * finished
1963 */
1965
1966/**
1967 * Allocate an AVFormatContext.
1968 * avformat_free_context() can be used to free the context and everything
1969 * allocated by the framework within it.
1970 */
1972
1973/**
1974 * Free an AVFormatContext and all its streams.
1975 * @param s context to free
1976 */
1978
1979/**
1980 * Get the AVClass for AVFormatContext. It can be used in combination with
1981 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
1982 *
1983 * @see av_opt_find().
1984 */
1985const AVClass *avformat_get_class(void);
1986
1987/**
1988 * Get the AVClass for AVStream. It can be used in combination with
1989 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
1990 *
1991 * @see av_opt_find().
1992 */
1993const AVClass *av_stream_get_class(void);
1994
1995/**
1996 * Get the AVClass for AVStreamGroup. It can be used in combination with
1997 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
1998 *
1999 * @see av_opt_find().
2000 */
2002
2003/**
2004 * @return a string identifying the stream group type, or NULL if unknown
2005 */
2007
2008/**
2009 * Add a new empty stream group to a media file.
2010 *
2011 * When demuxing, it may be called by the demuxer in read_header(). If the
2012 * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
2013 * be called in read_packet().
2014 *
2015 * When muxing, may be called by the user before avformat_write_header().
2016 *
2017 * User is required to call avformat_free_context() to clean up the allocation
2018 * by avformat_stream_group_create().
2019 *
2020 * New streams can be added to the group with avformat_stream_group_add_stream().
2021 *
2022 * @param s media file handle
2023 *
2024 * @return newly created group or NULL on error.
2025 * @see avformat_new_stream, avformat_stream_group_add_stream.
2026 */
2028 enum AVStreamGroupParamsType type,
2029 AVDictionary **options);
2030
2031/**
2032 * Add a new stream to a media file.
2033 *
2034 * When demuxing, it is called by the demuxer in read_header(). If the
2035 * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
2036 * be called in read_packet().
2037 *
2038 * When muxing, should be called by the user before avformat_write_header().
2039 *
2040 * User is required to call avformat_free_context() to clean up the allocation
2041 * by avformat_new_stream().
2042 *
2043 * @param s media file handle
2044 * @param c unused, does nothing
2045 *
2046 * @return newly created stream or NULL on error.
2047 */
2049
2050/**
2051 * Add an already allocated stream to a stream group.
2052 *
2053 * When demuxing, it may be called by the demuxer in read_header(). If the
2054 * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
2055 * be called in read_packet().
2056 *
2057 * When muxing, may be called by the user before avformat_write_header() after
2058 * having allocated a new group with avformat_stream_group_create() and stream with
2059 * avformat_new_stream().
2060 *
2061 * User is required to call avformat_free_context() to clean up the allocation
2062 * by avformat_stream_group_add_stream().
2063 *
2064 * @param stg stream group belonging to a media file.
2065 * @param st stream in the media file to add to the group.
2066 *
2067 * @retval 0 success
2068 * @retval AVERROR(EEXIST) the stream was already in the group
2069 * @retval "another negative error code" legitimate errors
2070 *
2071 * @see avformat_new_stream, avformat_stream_group_create.
2072 */
2074
2075#if FF_API_AVSTREAM_SIDE_DATA
2076/**
2077 * Wrap an existing array as stream side data.
2078 *
2079 * @param st stream
2080 * @param type side information type
2081 * @param data the side data array. It must be allocated with the av_malloc()
2082 * family of functions. The ownership of the data is transferred to
2083 * st.
2084 * @param size side information size
2085 *
2086 * @return zero on success, a negative AVERROR code on failure. On failure,
2087 * the stream is unchanged and the data remains owned by the caller.
2088 * @deprecated use av_packet_side_data_add() with the stream's
2089 * @ref AVCodecParameters.coded_side_data "codecpar side data"
2090 */
2092int av_stream_add_side_data(AVStream *st, enum AVPacketSideDataType type,
2093 uint8_t *data, size_t size);
2094
2095/**
2096 * Allocate new information from stream.
2097 *
2098 * @param stream stream
2099 * @param type desired side information type
2100 * @param size side information size
2101 *
2102 * @return pointer to fresh allocated data or NULL otherwise
2103 * @deprecated use av_packet_side_data_new() with the stream's
2104 * @ref AVCodecParameters.coded_side_data "codecpar side data"
2105 */
2107uint8_t *av_stream_new_side_data(AVStream *stream,
2108 enum AVPacketSideDataType type, size_t size);
2109/**
2110 * Get side information from stream.
2111 *
2112 * @param stream stream
2113 * @param type desired side information type
2114 * @param size If supplied, *size will be set to the size of the side data
2115 * or to zero if the desired side data is not present.
2116 *
2117 * @return pointer to data if present or NULL otherwise
2118 * @deprecated use av_packet_side_data_get() with the stream's
2119 * @ref AVCodecParameters.coded_side_data "codecpar side data"
2120 */
2122uint8_t *av_stream_get_side_data(const AVStream *stream,
2123 enum AVPacketSideDataType type, size_t *size);
2124#endif
2125
2127
2128/**
2129 * @}
2130 */
2131
2132
2133/**
2134 * Allocate an AVFormatContext for an output format.
2135 * avformat_free_context() can be used to free the context and
2136 * everything allocated by the framework within it.
2137 *
2138 * @param ctx pointee is set to the created format context,
2139 * or to NULL in case of failure
2140 * @param oformat format to use for allocating the context, if NULL
2141 * format_name and filename are used instead
2142 * @param format_name the name of output format to use for allocating the
2143 * context, if NULL filename is used instead
2144 * @param filename the name of the filename to use for allocating the
2145 * context, may be NULL
2146 *
2147 * @return >= 0 in case of success, a negative AVERROR code in case of
2148 * failure
2149 */
2151 const char *format_name, const char *filename);
2152
2153/**
2154 * @addtogroup lavf_decoding
2155 * @{
2156 */
2157
2158/**
2159 * Find AVInputFormat based on the short name of the input format.
2160 */
2161const AVInputFormat *av_find_input_format(const char *short_name);
2162
2163/**
2164 * Guess the file format.
2165 *
2166 * @param pd data to be probed
2167 * @param is_opened Whether the file is already opened; determines whether
2168 * demuxers with or without AVFMT_NOFILE are probed.
2169 */
2170const AVInputFormat *av_probe_input_format(const AVProbeData *pd, int is_opened);
2171
2172/**
2173 * Guess the file format.
2174 *
2175 * @param pd data to be probed
2176 * @param is_opened Whether the file is already opened; determines whether
2177 * demuxers with or without AVFMT_NOFILE are probed.
2178 * @param score_max A probe score larger that this is required to accept a
2179 * detection, the variable is set to the actual detection
2180 * score afterwards.
2181 * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
2182 * to retry with a larger probe buffer.
2183 */
2185 int is_opened, int *score_max);
2186
2187/**
2188 * Guess the file format.
2189 *
2190 * @param is_opened Whether the file is already opened; determines whether
2191 * demuxers with or without AVFMT_NOFILE are probed.
2192 * @param score_ret The score of the best detection.
2193 */
2195 int is_opened, int *score_ret);
2196
2197/**
2198 * Probe a bytestream to determine the input format. Each time a probe returns
2199 * with a score that is too low, the probe buffer size is increased and another
2200 * attempt is made. When the maximum probe size is reached, the input format
2201 * with the highest score is returned.
2202 *
2203 * @param pb the bytestream to probe
2204 * @param fmt the input format is put here
2205 * @param url the url of the stream
2206 * @param logctx the log context
2207 * @param offset the offset within the bytestream to probe from
2208 * @param max_probe_size the maximum probe buffer size (zero for default)
2209 *
2210 * @return the score in case of success, a negative value corresponding to an
2211 * the maximal score is AVPROBE_SCORE_MAX
2212 * AVERROR code otherwise
2213 */
2215 const char *url, void *logctx,
2216 unsigned int offset, unsigned int max_probe_size);
2217
2218/**
2219 * Like av_probe_input_buffer2() but returns 0 on success
2220 */
2222 const char *url, void *logctx,
2223 unsigned int offset, unsigned int max_probe_size);
2224
2225/**
2226 * Open an input stream and read the header. The codecs are not opened.
2227 * The stream must be closed with avformat_close_input().
2228 *
2229 * @param ps Pointer to user-supplied AVFormatContext (allocated by
2230 * avformat_alloc_context). May be a pointer to NULL, in
2231 * which case an AVFormatContext is allocated by this
2232 * function and written into ps.
2233 * Note that a user-supplied AVFormatContext will be freed
2234 * on failure.
2235 * @param url URL of the stream to open.
2236 * @param fmt If non-NULL, this parameter forces a specific input format.
2237 * Otherwise the format is autodetected.
2238 * @param options A dictionary filled with AVFormatContext and demuxer-private
2239 * options.
2240 * On return this parameter will be destroyed and replaced with
2241 * a dict containing options that were not found. May be NULL.
2242 *
2243 * @return 0 on success, a negative AVERROR on failure.
2244 *
2245 * @note If you want to use custom IO, preallocate the format context and set its pb field.
2246 */
2247int avformat_open_input(AVFormatContext **ps, const char *url,
2248 const AVInputFormat *fmt, AVDictionary **options);
2249
2250/**
2251 * Read packets of a media file to get stream information. This
2252 * is useful for file formats with no headers such as MPEG. This
2253 * function also computes the real framerate in case of MPEG-2 repeat
2254 * frame mode.
2255 * The logical file position is not changed by this function;
2256 * examined packets may be buffered for later processing.
2257 *
2258 * @param ic media file handle
2259 * @param options If non-NULL, an ic.nb_streams long array of pointers to
2260 * dictionaries, where i-th member contains options for
2261 * codec corresponding to i-th stream.
2262 * On return each dictionary will be filled with options that were not found.
2263 * @return >=0 if OK, AVERROR_xxx on error
2264 *
2265 * @note this function isn't guaranteed to open all the codecs, so
2266 * options being non-empty at return is a perfectly normal behavior.
2267 *
2268 * @todo Let the user decide somehow what information is needed so that
2269 * we do not waste time getting stuff the user does not need.
2270 */
2272
2273/**
2274 * Find the programs which belong to a given stream.
2275 *
2276 * @param ic media file handle
2277 * @param last the last found program, the search will start after this
2278 * program, or from the beginning if it is NULL
2279 * @param s stream index
2280 *
2281 * @return the next program which belongs to s, NULL if no program is found or
2282 * the last program is not among the programs of ic.
2283 */
2285
2286void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx);
2287
2288/**
2289 * Find the "best" stream in the file.
2290 * The best stream is determined according to various heuristics as the most
2291 * likely to be what the user expects.
2292 * If the decoder parameter is non-NULL, av_find_best_stream will find the
2293 * default decoder for the stream's codec; streams for which no decoder can
2294 * be found are ignored.
2295 *
2296 * @param ic media file handle
2297 * @param type stream type: video, audio, subtitles, etc.
2298 * @param wanted_stream_nb user-requested stream number,
2299 * or -1 for automatic selection
2300 * @param related_stream try to find a stream related (eg. in the same
2301 * program) to this one, or -1 if none
2302 * @param decoder_ret if non-NULL, returns the decoder for the
2303 * selected stream
2304 * @param flags flags; none are currently defined
2305 *
2306 * @return the non-negative stream number in case of success,
2307 * AVERROR_STREAM_NOT_FOUND if no stream with the requested type
2308 * could be found,
2309 * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
2310 *
2311 * @note If av_find_best_stream returns successfully and decoder_ret is not
2312 * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
2313 */
2315 enum AVMediaType type,
2316 int wanted_stream_nb,
2317 int related_stream,
2318 const struct AVCodec **decoder_ret,
2319 int flags);
2320
2321/**
2322 * Return the next frame of a stream.
2323 * This function returns what is stored in the file, and does not validate
2324 * that what is there are valid frames for the decoder. It will split what is
2325 * stored in the file into frames and return one for each call. It will not
2326 * omit invalid data between valid frames so as to give the decoder the maximum
2327 * information possible for decoding.
2328 *
2329 * On success, the returned packet is reference-counted (pkt->buf is set) and
2330 * valid indefinitely. The packet must be freed with av_packet_unref() when
2331 * it is no longer needed. For video, the packet contains exactly one frame.
2332 * For audio, it contains an integer number of frames if each frame has
2333 * a known fixed size (e.g. PCM or ADPCM data). If the audio frames have
2334 * a variable size (e.g. MPEG audio), then it contains one frame.
2335 *
2336 * pkt->pts, pkt->dts and pkt->duration are always set to correct
2337 * values in AVStream.time_base units (and guessed if the format cannot
2338 * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
2339 * has B-frames, so it is better to rely on pkt->dts if you do not
2340 * decompress the payload.
2341 *
2342 * @return 0 if OK, < 0 on error or end of file. On error, pkt will be blank
2343 * (as if it came from av_packet_alloc()).
2344 *
2345 * @note pkt will be initialized, so it may be uninitialized, but it must not
2346 * contain data that needs to be freed.
2347 */
2349
2350/**
2351 * Seek to the keyframe at timestamp.
2352 * 'timestamp' in 'stream_index'.
2353 *
2354 * @param s media file handle
2355 * @param stream_index If stream_index is (-1), a default stream is selected,
2356 * and timestamp is automatically converted from
2357 * AV_TIME_BASE units to the stream specific time_base.
2358 * @param timestamp Timestamp in AVStream.time_base units or, if no stream
2359 * is specified, in AV_TIME_BASE units.
2360 * @param flags flags which select direction and seeking mode
2361 *
2362 * @return >= 0 on success
2363 */
2364int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
2365 int flags);
2366
2367/**
2368 * Seek to timestamp ts.
2369 * Seeking will be done so that the point from which all active streams
2370 * can be presented successfully will be closest to ts and within min/max_ts.
2371 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
2372 *
2373 * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
2374 * are the file position (this may not be supported by all demuxers).
2375 * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
2376 * in the stream with stream_index (this may not be supported by all demuxers).
2377 * Otherwise all timestamps are in units of the stream selected by stream_index
2378 * or if stream_index is -1, in AV_TIME_BASE units.
2379 * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
2380 * keyframes (this may not be supported by all demuxers).
2381 * If flags contain AVSEEK_FLAG_BACKWARD, it is ignored.
2382 *
2383 * @param s media file handle
2384 * @param stream_index index of the stream which is used as time base reference
2385 * @param min_ts smallest acceptable timestamp
2386 * @param ts target timestamp
2387 * @param max_ts largest acceptable timestamp
2388 * @param flags flags
2389 * @return >=0 on success, error code otherwise
2390 *
2391 * @note This is part of the new seek API which is still under construction.
2392 */
2393int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
2394
2395/**
2396 * Discard all internally buffered data. This can be useful when dealing with
2397 * discontinuities in the byte stream. Generally works only with formats that
2398 * can resync. This includes headerless formats like MPEG-TS/TS but should also
2399 * work with NUT, Ogg and in a limited way AVI for example.
2400 *
2401 * The set of streams, the detected duration, stream parameters and codecs do
2402 * not change when calling this function. If you want a complete reset, it's
2403 * better to open a new AVFormatContext.
2404 *
2405 * This does not flush the AVIOContext (s->pb). If necessary, call
2406 * avio_flush(s->pb) before calling this function.
2407 *
2408 * @param s media file handle
2409 * @return >=0 on success, error code otherwise
2410 */
2412
2413/**
2414 * Start playing a network-based stream (e.g. RTSP stream) at the
2415 * current position.
2416 */
2418
2419/**
2420 * Pause a network-based stream (e.g. RTSP stream).
2421 *
2422 * Use av_read_play() to resume it.
2423 */
2425
2426/**
2427 * Close an opened input AVFormatContext. Free it and all its contents
2428 * and set *s to NULL.
2429 */
2431/**
2432 * @}
2435#define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
2436#define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
2437#define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
2438#define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
2439
2440/**
2441 * @addtogroup lavf_encoding
2442 * @{
2445#define AVSTREAM_INIT_IN_WRITE_HEADER 0 ///< stream parameters initialized in avformat_write_header
2446#define AVSTREAM_INIT_IN_INIT_OUTPUT 1 ///< stream parameters initialized in avformat_init_output
2447
2448/**
2449 * Allocate the stream private data and write the stream header to
2450 * an output media file.
2451 *
2452 * @param s Media file handle, must be allocated with
2453 * avformat_alloc_context().
2454 * Its \ref AVFormatContext.oformat "oformat" field must be set
2455 * to the desired output format;
2456 * Its \ref AVFormatContext.pb "pb" field must be set to an
2457 * already opened ::AVIOContext.
2458 * @param options An ::AVDictionary filled with AVFormatContext and
2459 * muxer-private options.
2460 * On return this parameter will be destroyed and replaced with
2461 * a dict containing options that were not found. May be NULL.
2462 *
2463 * @retval AVSTREAM_INIT_IN_WRITE_HEADER On success, if the codec had not already been
2464 * fully initialized in avformat_init_output().
2465 * @retval AVSTREAM_INIT_IN_INIT_OUTPUT On success, if the codec had already been fully
2466 * initialized in avformat_init_output().
2467 * @retval AVERROR A negative AVERROR on failure.
2468 *
2469 * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_init_output.
2473
2474/**
2475 * Allocate the stream private data and initialize the codec, but do not write the header.
2476 * May optionally be used before avformat_write_header() to initialize stream parameters
2477 * before actually writing the header.
2478 * If using this function, do not pass the same options to avformat_write_header().
2479 *
2480 * @param s Media file handle, must be allocated with
2481 * avformat_alloc_context().
2482 * Its \ref AVFormatContext.oformat "oformat" field must be set
2483 * to the desired output format;
2484 * Its \ref AVFormatContext.pb "pb" field must be set to an
2485 * already opened ::AVIOContext.
2486 * @param options An ::AVDictionary filled with AVFormatContext and
2487 * muxer-private options.
2488 * On return this parameter will be destroyed and replaced with
2489 * a dict containing options that were not found. May be NULL.
2490 *
2491 * @retval AVSTREAM_INIT_IN_WRITE_HEADER On success, if the codec requires
2492 * avformat_write_header to fully initialize.
2493 * @retval AVSTREAM_INIT_IN_INIT_OUTPUT On success, if the codec has been fully
2494 * initialized.
2495 * @retval AVERROR Anegative AVERROR on failure.
2496 *
2497 * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_write_header.
2501
2502/**
2503 * Write a packet to an output media file.
2504 *
2505 * This function passes the packet directly to the muxer, without any buffering
2506 * or reordering. The caller is responsible for correctly interleaving the
2507 * packets if the format requires it. Callers that want libavformat to handle
2508 * the interleaving should call av_interleaved_write_frame() instead of this
2509 * function.
2510 *
2511 * @param s media file handle
2512 * @param pkt The packet containing the data to be written. Note that unlike
2513 * av_interleaved_write_frame(), this function does not take
2514 * ownership of the packet passed to it (though some muxers may make
2515 * an internal reference to the input packet).
2516 * <br>
2517 * This parameter can be NULL (at any time, not just at the end), in
2518 * order to immediately flush data buffered within the muxer, for
2519 * muxers that buffer up data internally before writing it to the
2520 * output.
2521 * <br>
2522 * Packet's @ref AVPacket.stream_index "stream_index" field must be
2523 * set to the index of the corresponding stream in @ref
2524 * AVFormatContext.streams "s->streams".
2525 * <br>
2526 * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2527 * must be set to correct values in the stream's timebase (unless the
2528 * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2529 * they can be set to AV_NOPTS_VALUE).
2530 * The dts for subsequent packets passed to this function must be strictly
2531 * increasing when compared in their respective timebases (unless the
2532 * output format is flagged with the AVFMT_TS_NONSTRICT, then they
2533 * merely have to be nondecreasing). @ref AVPacket.duration
2534 * "duration") should also be set if known.
2535 * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush
2536 *
2537 * @see av_interleaved_write_frame()
2538 */
2540
2541/**
2542 * Write a packet to an output media file ensuring correct interleaving.
2543 *
2544 * This function will buffer the packets internally as needed to make sure the
2545 * packets in the output file are properly interleaved, usually ordered by
2546 * increasing dts. Callers doing their own interleaving should call
2547 * av_write_frame() instead of this function.
2548 *
2549 * Using this function instead of av_write_frame() can give muxers advance
2550 * knowledge of future packets, improving e.g. the behaviour of the mp4
2551 * muxer for VFR content in fragmenting mode.
2552 *
2553 * @param s media file handle
2554 * @param pkt The packet containing the data to be written.
2555 * <br>
2556 * If the packet is reference-counted, this function will take
2557 * ownership of this reference and unreference it later when it sees
2558 * fit. If the packet is not reference-counted, libavformat will
2559 * make a copy.
2560 * The returned packet will be blank (as if returned from
2561 * av_packet_alloc()), even on error.
2562 * <br>
2563 * This parameter can be NULL (at any time, not just at the end), to
2564 * flush the interleaving queues.
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 in one stream must be strictly
2575 * increasing (unless the output format is flagged with the
2576 * AVFMT_TS_NONSTRICT, then they merely have to be nondecreasing).
2577 * @ref AVPacket.duration "duration" should also be set if known.
2578 *
2579 * @return 0 on success, a negative AVERROR on error.
2580 *
2581 * @see av_write_frame(), AVFormatContext.max_interleave_delta
2582 */
2584
2585/**
2586 * Write an uncoded frame to an output media file.
2587 *
2588 * The frame must be correctly interleaved according to the container
2589 * specification; if not, av_interleaved_write_uncoded_frame() must be used.
2590 *
2591 * See av_interleaved_write_uncoded_frame() for details.
2592 */
2593int av_write_uncoded_frame(AVFormatContext *s, int stream_index,
2594 struct AVFrame *frame);
2595
2596/**
2597 * Write an uncoded frame to an output media file.
2598 *
2599 * If the muxer supports it, this function makes it possible to write an AVFrame
2600 * structure directly, without encoding it into a packet.
2601 * It is mostly useful for devices and similar special muxers that use raw
2602 * video or PCM data and will not serialize it into a byte stream.
2603 *
2604 * To test whether it is possible to use it with a given muxer and stream,
2605 * use av_write_uncoded_frame_query().
2606 *
2607 * The caller gives up ownership of the frame and must not access it
2608 * afterwards.
2609 *
2610 * @return >=0 for success, a negative code on error
2611 */
2613 struct AVFrame *frame);
2614
2615/**
2616 * Test whether a muxer supports uncoded frame.
2617 *
2618 * @return >=0 if an uncoded frame can be written to that muxer and stream,
2619 * <0 if not
2620 */
2621int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index);
2622
2623/**
2624 * Write the stream trailer to an output media file and free the
2625 * file private data.
2626 *
2627 * May only be called after a successful call to avformat_write_header.
2628 *
2629 * @param s media file handle
2630 * @return 0 if OK, AVERROR_xxx on error
2631 */
2633
2634/**
2635 * Return the output format in the list of registered output formats
2636 * which best matches the provided parameters, or return NULL if
2637 * there is no match.
2638 *
2639 * @param short_name if non-NULL checks if short_name matches with the
2640 * names of the registered formats
2641 * @param filename if non-NULL checks if filename terminates with the
2642 * extensions of the registered formats
2643 * @param mime_type if non-NULL checks if mime_type matches with the
2644 * MIME type of the registered formats
2645 */
2646const AVOutputFormat *av_guess_format(const char *short_name,
2647 const char *filename,
2648 const char *mime_type);
2649
2650/**
2651 * Guess the codec ID based upon muxer and filename.
2652 */
2653enum AVCodecID av_guess_codec(const AVOutputFormat *fmt, const char *short_name,
2654 const char *filename, const char *mime_type,
2655 enum AVMediaType type);
2656
2657/**
2658 * Get timing information for the data currently output.
2659 * The exact meaning of "currently output" depends on the format.
2660 * It is mostly relevant for devices that have an internal buffer and/or
2661 * work in real time.
2662 * @param s media file handle
2663 * @param stream stream in the media file
2664 * @param[out] dts DTS of the last packet output for the stream, in stream
2665 * time_base units
2666 * @param[out] wall absolute time when that packet whas output,
2667 * in microsecond
2668 * @retval 0 Success
2669 * @retval AVERROR(ENOSYS) The format does not support it
2670 *
2671 * @note Some formats or devices may not allow to measure dts and wall
2672 * atomically.
2673 */
2674int av_get_output_timestamp(struct AVFormatContext *s, int stream,
2675 int64_t *dts, int64_t *wall);
2676
2677
2678/**
2679 * @}
2680 */
2681
2682
2683/**
2684 * @defgroup lavf_misc Utility functions
2685 * @ingroup libavf
2686 * @{
2687 *
2688 * Miscellaneous utility functions related to both muxing and demuxing
2689 * (or neither).
2690 */
2691
2692/**
2693 * Send a nice hexadecimal dump of a buffer to the specified file stream.
2694 *
2695 * @param f The file stream pointer where the dump should be sent to.
2696 * @param buf buffer
2697 * @param size buffer size
2698 *
2699 * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2
2700 */
2701void av_hex_dump(FILE *f, const uint8_t *buf, int size);
2702
2703/**
2704 * Send a nice hexadecimal dump of a buffer to the log.
2705 *
2706 * @param avcl A pointer to an arbitrary struct of which the first field is a
2707 * pointer to an AVClass struct.
2708 * @param level The importance level of the message, lower values signifying
2709 * higher importance.
2710 * @param buf buffer
2711 * @param size buffer size
2712 *
2713 * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2
2714 */
2715void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size);
2716
2717/**
2718 * Send a nice dump of a packet to the specified file stream.
2719 *
2720 * @param f The file stream pointer where the dump should be sent to.
2721 * @param pkt packet to dump
2722 * @param dump_payload True if the payload must be displayed, too.
2723 * @param st AVStream that the packet belongs to
2724 */
2725void av_pkt_dump2(FILE *f, const AVPacket *pkt, int dump_payload, const AVStream *st);
2726
2727
2728/**
2729 * Send a nice dump of a packet to the log.
2730 *
2731 * @param avcl A pointer to an arbitrary struct of which the first field is a
2732 * pointer to an AVClass struct.
2733 * @param level The importance level of the message, lower values signifying
2734 * higher importance.
2735 * @param pkt packet to dump
2736 * @param dump_payload True if the payload must be displayed, too.
2737 * @param st AVStream that the packet belongs to
2738 */
2739void av_pkt_dump_log2(void *avcl, int level, const AVPacket *pkt, int dump_payload,
2740 const AVStream *st);
2741
2742/**
2743 * Get the AVCodecID for the given codec tag tag.
2744 * If no codec id is found returns AV_CODEC_ID_NONE.
2745 *
2746 * @param tags list of supported codec_id-codec_tag pairs, as stored
2747 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2748 * @param tag codec tag to match to a codec ID
2749 */
2750enum AVCodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
2751
2752/**
2753 * Get the codec tag for the given codec id id.
2754 * If no codec tag is found returns 0.
2755 *
2756 * @param tags list of supported codec_id-codec_tag pairs, as stored
2757 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2758 * @param id codec ID to match to a codec tag
2759 */
2760unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id);
2761
2762/**
2763 * Get the codec tag for the given codec id.
2764 *
2765 * @param tags list of supported codec_id - codec_tag pairs, as stored
2766 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2767 * @param id codec id that should be searched for in the list
2768 * @param tag A pointer to the found tag
2769 * @return 0 if id was not found in tags, > 0 if it was found
2770 */
2771int av_codec_get_tag2(const struct AVCodecTag * const *tags, enum AVCodecID id,
2772 unsigned int *tag);
2773
2775
2776/**
2777 * Get the index for a specific timestamp.
2778 *
2779 * @param st stream that the timestamp belongs to
2780 * @param timestamp timestamp to retrieve the index for
2781 * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
2782 * to the timestamp which is <= the requested one, if backward
2783 * is 0, then it will be >=
2784 * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
2785 * @return < 0 if no such timestamp could be found
2786 */
2787int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
2788
2789/**
2790 * Get the index entry count for the given AVStream.
2791 *
2792 * @param st stream
2793 * @return the number of index entries in the stream
2794 */
2796
2797/**
2798 * Get the AVIndexEntry corresponding to the given index.
2799 *
2800 * @param st Stream containing the requested AVIndexEntry.
2801 * @param idx The desired index.
2802 * @return A pointer to the requested AVIndexEntry if it exists, NULL otherwise.
2803 *
2804 * @note The pointer returned by this function is only guaranteed to be valid
2805 * until any function that takes the stream or the parent AVFormatContext
2806 * as input argument is called.
2807 */
2809
2810/**
2811 * Get the AVIndexEntry corresponding to the given timestamp.
2812 *
2813 * @param st Stream containing the requested AVIndexEntry.
2814 * @param wanted_timestamp Timestamp to retrieve the index entry for.
2815 * @param flags If AVSEEK_FLAG_BACKWARD then the returned entry will correspond
2816 * to the timestamp which is <= the requested one, if backward
2817 * is 0, then it will be >=
2818 * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise.
2819 * @return A pointer to the requested AVIndexEntry if it exists, NULL otherwise.
2820 *
2821 * @note The pointer returned by this function is only guaranteed to be valid
2822 * until any function that takes the stream or the parent AVFormatContext
2823 * as input argument is called.
2824 */
2826 int64_t wanted_timestamp,
2827 int flags);
2828/**
2829 * Add an index entry into a sorted list. Update the entry if the list
2830 * already contains it.
2831 *
2832 * @param timestamp timestamp in the time base of the given stream
2833 */
2834int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
2835 int size, int distance, int flags);
2836
2837
2838/**
2839 * Split a URL string into components.
2840 *
2841 * The pointers to buffers for storing individual components may be null,
2842 * in order to ignore that component. Buffers for components not found are
2843 * set to empty strings. If the port is not found, it is set to a negative
2844 * value.
2845 *
2846 * @param proto the buffer for the protocol
2847 * @param proto_size the size of the proto buffer
2848 * @param authorization the buffer for the authorization
2849 * @param authorization_size the size of the authorization buffer
2850 * @param hostname the buffer for the host name
2851 * @param hostname_size the size of the hostname buffer
2852 * @param port_ptr a pointer to store the port number in
2853 * @param path the buffer for the path
2854 * @param path_size the size of the path buffer
2855 * @param url the URL to split
2856 */
2857void av_url_split(char *proto, int proto_size,
2858 char *authorization, int authorization_size,
2859 char *hostname, int hostname_size,
2860 int *port_ptr,
2861 char *path, int path_size,
2862 const char *url);
2863
2864
2865/**
2866 * Print detailed information about the input or output format, such as
2867 * duration, bitrate, streams, container, programs, metadata, side data,
2868 * codec and time base.
2869 *
2870 * @param ic the context to analyze
2871 * @param index index of the stream to dump information about
2872 * @param url the URL to print, such as source or destination file
2873 * @param is_output Select whether the specified context is an input(0) or output(1)
2874 */
2876 int index,
2877 const char *url,
2878 int is_output);
2880
2881#define AV_FRAME_FILENAME_FLAGS_MULTIPLE 1 ///< Allow multiple %d
2882
2883/**
2884 * Return in 'buf' the path with '%d' replaced by a number.
2885 *
2886 * Also handles the '%0nd' format where 'n' is the total number
2887 * of digits and '%%'.
2888 *
2889 * @param buf destination buffer
2890 * @param buf_size destination buffer size
2891 * @param path numbered sequence string
2892 * @param number frame number
2893 * @param flags AV_FRAME_FILENAME_FLAGS_*
2894 * @return 0 if OK, -1 on format error
2895 */
2896int av_get_frame_filename2(char *buf, int buf_size,
2897 const char *path, int number, int flags);
2898
2899int av_get_frame_filename(char *buf, int buf_size,
2900 const char *path, int number);
2901
2902/**
2903 * Check whether filename actually is a numbered sequence generator.
2904 *
2905 * @param filename possible numbered sequence string
2906 * @return 1 if a valid numbered sequence string, 0 otherwise
2907 */
2908int av_filename_number_test(const char *filename);
2909
2910/**
2911 * Generate an SDP for an RTP session.
2912 *
2913 * Note, this overwrites the id values of AVStreams in the muxer contexts
2914 * for getting unique dynamic payload types.
2915 *
2916 * @param ac array of AVFormatContexts describing the RTP streams. If the
2917 * array is composed by only one context, such context can contain
2918 * multiple AVStreams (one AVStream per RTP stream). Otherwise,
2919 * all the contexts in the array (an AVCodecContext per RTP stream)
2920 * must contain only one AVStream.
2921 * @param n_files number of AVCodecContexts contained in ac
2922 * @param buf buffer where the SDP will be stored (must be allocated by
2923 * the caller)
2924 * @param size the size of the buffer
2925 * @return 0 if OK, AVERROR_xxx on error
2926 */
2927int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size);
2928
2929/**
2930 * Return a positive value if the given filename has one of the given
2931 * extensions, 0 otherwise.
2932 *
2933 * @param filename file name to check against the given extensions
2934 * @param extensions a comma-separated list of filename extensions
2935 */
2936int av_match_ext(const char *filename, const char *extensions);
2937
2938/**
2939 * Test if the given container can store a codec.
2940 *
2941 * @param ofmt container to check for compatibility
2942 * @param codec_id codec to potentially store in container
2943 * @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
2944 *
2945 * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
2946 * A negative number if this information is not available.
2947 */
2948int avformat_query_codec(const AVOutputFormat *ofmt, enum AVCodecID codec_id,
2949 int std_compliance);
2950
2951/**
2952 * @defgroup riff_fourcc RIFF FourCCs
2953 * @{
2954 * Get the tables mapping RIFF FourCCs to libavcodec AVCodecIDs. The tables are
2955 * meant to be passed to av_codec_get_id()/av_codec_get_tag() as in the
2956 * following code:
2957 * @code
2958 * uint32_t tag = MKTAG('H', '2', '6', '4');
2959 * const struct AVCodecTag *table[] = { avformat_get_riff_video_tags(), 0 };
2960 * enum AVCodecID id = av_codec_get_id(table, tag);
2961 * @endcode
2962 */
2963/**
2964 * @return the table mapping RIFF FourCCs for video to libavcodec AVCodecID.
2965 */
2966const struct AVCodecTag *avformat_get_riff_video_tags(void);
2967/**
2968 * @return the table mapping RIFF FourCCs for audio to AVCodecID.
2969 */
2970const struct AVCodecTag *avformat_get_riff_audio_tags(void);
2971/**
2972 * @return the table mapping MOV FourCCs for video to libavcodec AVCodecID.
2973 */
2974const struct AVCodecTag *avformat_get_mov_video_tags(void);
2975/**
2976 * @return the table mapping MOV FourCCs for audio to AVCodecID.
2977 */
2978const struct AVCodecTag *avformat_get_mov_audio_tags(void);
2979
2980/**
2981 * @}
2982 */
2983
2984/**
2985 * Guess the sample aspect ratio of a frame, based on both the stream and the
2986 * frame aspect ratio.
2987 *
2988 * Since the frame aspect ratio is set by the codec but the stream aspect ratio
2989 * is set by the demuxer, these two may not be equal. This function tries to
2990 * return the value that you should use if you would like to display the frame.
2991 *
2992 * Basic logic is to use the stream aspect ratio if it is set to something sane
2993 * otherwise use the frame aspect ratio. This way a container setting, which is
2994 * usually easy to modify can override the coded value in the frames.
2995 *
2996 * @param format the format context which the stream is part of
2997 * @param stream the stream which the frame is part of
2998 * @param frame the frame with the aspect ratio to be determined
2999 * @return the guessed (valid) sample_aspect_ratio, 0/1 if no idea
3000 */
3002 struct AVFrame *frame);
3003
3004/**
3005 * Guess the frame rate, based on both the container and codec information.
3006 *
3007 * @param ctx the format context which the stream is part of
3008 * @param stream the stream which the frame is part of
3009 * @param frame the frame for which the frame rate should be determined, may be NULL
3010 * @return the guessed (valid) frame rate, 0/1 if no idea
3011 */
3013 struct AVFrame *frame);
3014
3015/**
3016 * Check if the stream st contained in s is matched by the stream specifier
3017 * spec.
3018 *
3019 * See the "stream specifiers" chapter in the documentation for the syntax
3020 * of spec.
3021 *
3022 * @return >0 if st is matched by spec;
3023 * 0 if st is not matched by spec;
3024 * AVERROR code if spec is invalid
3025 *
3026 * @note A stream specifier can match several streams in the format.
3027 */
3029 const char *spec);
3030
3037#if FF_API_R_FRAME_RATE
3038 AVFMT_TBCF_R_FRAMERATE,
3039#endif
3040};
3041
3042/**
3043 * Transfer internal timing information from one stream to another.
3044 *
3045 * This function is useful when doing stream copy.
3046 *
3047 * @param ofmt target output format for ost
3048 * @param ost output stream which needs timings copy and adjustments
3049 * @param ist reference input stream to copy timings from
3050 * @param copy_tb define from where the stream codec timebase needs to be imported
3051 */
3053 AVStream *ost, const AVStream *ist,
3054 enum AVTimebaseSource copy_tb);
3055
3056/**
3057 * Get the internal codec timebase from a stream.
3058 *
3059 * @param st input stream to extract the timebase from
3060 */
3062
3063/**
3064 * @}
3065 */
3066
3067#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:1080
@ AV_STREAM_GROUP_PARAMS_NONE
Definition avformat.h:1081
@ AV_STREAM_GROUP_PARAMS_IAMF_MIX_PRESENTATION
Definition avformat.h:1083
@ AV_STREAM_GROUP_PARAMS_TILE_GRID
Definition avformat.h:1084
@ AV_STREAM_GROUP_PARAMS_IAMF_AUDIO_ELEMENT
Definition avformat.h:1082
int(* AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options)
Definition avformat.h:1228
AVDurationEstimationMethod
The duration of a video can be estimated through various ways, and this enum can be used to know how ...
Definition avformat.h:1235
@ AVFMT_DURATION_FROM_BITRATE
Duration estimated from bitrate (less accurate)
Definition avformat.h:1238
@ AVFMT_DURATION_FROM_PTS
Duration accurately estimated from PTSes.
Definition avformat.h:1236
@ AVFMT_DURATION_FROM_STREAM
Duration estimated from a stream with a known duration.
Definition avformat.h:1237
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:1225
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:210
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.
AVRational av_stream_get_codec_timebase(const AVStream *st)
Get the internal codec timebase from a stream.
const AVIndexEntry * avformat_index_get_entry(AVStream *st, int idx)
Get the AVIndexEntry corresponding to the given index.
AVTimebaseSource
Definition avformat.h:3031
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,...
int avformat_transfer_internal_stream_timing_info(const AVOutputFormat *ofmt, AVStream *ost, const AVStream *ist, enum AVTimebaseSource copy_tb)
Transfer internal timing information from one stream to another.
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.
@ AVFMT_TBCF_DEMUXER
Definition avformat.h:3034
@ AVFMT_TBCF_AUTO
Definition avformat.h:3032
@ AVFMT_TBCF_DECODER
Definition avformat.h:3033
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:1215
int64_t start
Definition avformat.h:1217
AVDictionary * metadata
Definition avformat.h:1218
int64_t end
chapter start/end time in time_base units
Definition avformat.h:1217
AVRational time_base
time base in which the start/end timestamps are specified
Definition avformat.h:1216
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:1255
int64_t max_interleave_delta
Maximum buffering duration for interleaving.
Definition avformat.h:1577
int event_flags
Flags indicating events happening on the file, a combination of AVFMT_EVENT_FLAG_*.
Definition avformat.h:1625
int avoid_negative_ts
Avoid negative timestamps during muxing.
Definition avformat.h:1642
unsigned int packet_size
Definition avformat.h:1399
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition avformat.h:1311
const AVClass * av_class
A class for logging and AVOptions.
Definition avformat.h:1260
int max_streams
The maximum number of streams.
Definition avformat.h:1541
int(* io_close2)(struct AVFormatContext *s, AVIOContext *pb)
A callback for closing the streams opened with AVFormatContext.io_open().
Definition avformat.h:1870
const uint8_t * key
Definition avformat.h:1452
AVStreamGroup ** stream_groups
A list of all stream groups in the file.
Definition avformat.h:1342
enum AVCodecID audio_codec_id
Forced audio codec_id.
Definition avformat.h:1468
AVIOContext * pb
I/O context.
Definition avformat.h:1297
int flush_packets
Flush the I/O context after each packet.
Definition avformat.h:1712
enum AVCodecID data_codec_id
Forced Data codec_id.
Definition avformat.h:1480
int64_t start_time
Position of the first frame of the component, in AV_TIME_BASE fractional seconds.
Definition avformat.h:1380
const struct AVCodec * data_codec
Forced data codec.
Definition avformat.h:1802
AVDictionary * metadata
Metadata that applies to the whole file.
Definition avformat.h:1490
int flags
Flags modifying the (de)muxer behaviour.
Definition avformat.h:1406
const struct AVOutputFormat * oformat
The output container format.
Definition avformat.h:1274
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:1599
int seek2any
Force seeking to any (also non key) frames.
Definition avformat.h:1705
int io_repositioned
IO repositioned flag.
Definition avformat.h:1770
AVProgram ** programs
Definition avformat.h:1456
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:1450
int ctx_flags
Flags signalling stream properties.
Definition avformat.h:1304
int strict_std_compliance
Allow non-standard and experimental extension.
Definition avformat.h:1612
int fps_probe_size
The number of frames used for determining the framerate in avformat_find_stream_info().
Definition avformat.h:1510
const struct AVCodec * audio_codec
Forced audio codec.
Definition avformat.h:1786
unsigned int nb_programs
Definition avformat.h:1455
AVIOInterruptCB interrupt_callback
Custom interrupt callbacks for the I/O layer.
Definition avformat.h:1528
int avio_flags
avio flags, used to force AVIO_FLAG_DIRECT.
Definition avformat.h:1676
char * url
input or output URL.
Definition avformat.h:1371
int probe_score
format probing score.
Definition avformat.h:1721
const struct AVInputFormat * iformat
The input container format.
Definition avformat.h:1267
unsigned int nb_chapters
Number of chapters in AVChapter array.
Definition avformat.h:1355
int metadata_header_padding
Number of bytes to be written as padding in a metadata header.
Definition avformat.h:1809
int64_t output_ts_offset
Output timestamp offset, in microseconds.
Definition avformat.h:1826
void * opaque
User data.
Definition avformat.h:1815
int format_probesize
Maximum number of bytes read from input in order to identify the input format.
Definition avformat.h:1732
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:1662
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:1684
int64_t bit_rate
Total stream bitrate in bit/s, 0 if not available.
Definition avformat.h:1397
char * codec_whitelist
',' separated list of allowed decoders.
Definition avformat.h:1740
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:1503
unsigned int max_index_size
Maximum amount of memory in bytes to use for the index of each stream.
Definition avformat.h:1553
enum AVCodecID video_codec_id
Forced video codec_id.
Definition avformat.h:1462
int debug
Flags to enable debugging.
Definition avformat.h:1533
av_format_control_message control_message_cb
Callback used by devices to communicate with application.
Definition avformat.h:1820
char * format_whitelist
',' separated list of allowed demuxers.
Definition avformat.h:1748
int audio_preload
Audio preload in microseconds.
Definition avformat.h:1654
AVChapter ** chapters
Definition avformat.h:1356
unsigned int nb_stream_groups
Number of elements in AVFormatContext.stream_groups.
Definition avformat.h:1330
void * priv_data
Format private data.
Definition avformat.h:1283
int64_t probesize
Maximum number of bytes read from input in order to determine stream properties.
Definition avformat.h:1442
enum AVCodecID subtitle_codec_id
Forced subtitle codec_id.
Definition avformat.h:1474
AVStream ** streams
A list of all streams in the file.
Definition avformat.h:1323
int64_t duration
Duration of the stream, in AV_TIME_BASE fractional seconds.
Definition avformat.h:1390
int max_ts_probe
Maximum number of packets to read while waiting for the first timestamp.
Definition avformat.h:1583
int64_t skip_initial_bytes
Skip initial bytes when opening stream.
Definition avformat.h:1691
const struct AVCodec * subtitle_codec
Forced subtitle codec.
Definition avformat.h:1794
char * protocol_whitelist
',' separated list of allowed protocols.
Definition avformat.h:1755
char * protocol_blacklist
',' separated list of disallowed protocols.
Definition avformat.h:1762
unsigned int max_picture_buffer
Maximum amount of memory in bytes to use for buffering frames obtained from realtime capture devices.
Definition avformat.h:1559
int max_chunk_duration
Max chunk time in microseconds.
Definition avformat.h:1591
const struct AVCodec * video_codec
Forced video codec.
Definition avformat.h:1778
int skip_estimate_duration_from_pts
Skip duration calcuation in estimate_timings_from_pts.
Definition avformat.h:1669
int error_recognition
Error recognition; higher values will detect more errors but may misdetect some more or less valid pa...
Definition avformat.h:1517
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:1856
int max_probe_packets
Maximum number of packets that can be probed.
Definition avformat.h:1606
unsigned int correct_ts_overflow
Correct single timestamp overflows.
Definition avformat.h:1698
uint8_t * dump_separator
dump format separator.
Definition avformat.h:1834
This structure describes decoded (raw) audio or video data.
Definition frame.h:344
Information on how to combine one or more audio streams, as defined in section 3.6 of IAMF.
Definition iamf.h:347
Information on how to render and mix one or more AVIAMFAudioElement to generate the final audio outpu...
Definition iamf.h:600
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:373
This structure stores compressed data.
Definition packet.h:499
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:1179
int pmt_pid
Definition avformat.h:1188
unsigned int nb_stream_indexes
Definition avformat.h:1184
int64_t start_time
Definition avformat.h:1199
int program_num
Definition avformat.h:1187
int64_t end_time
Definition avformat.h:1200
unsigned int * stream_index
Definition avformat.h:1183
int pcr_pid
Definition avformat.h:1189
int64_t pts_wrap_reference
reference dts for wrap detection
Definition avformat.h:1202
enum AVDiscard discard
selects which program to discard and which to feed to the caller
Definition avformat.h:1182
int pts_wrap_behavior
behavior on wrap detection
Definition avformat.h:1203
int pmt_version
Definition avformat.h:1190
AVDictionary * metadata
Definition avformat.h:1185
Rational number (pair of numerator and denominator).
Definition rational.h:58
AVStreamGroupTileGrid holds information on how to combine several independent images on a single canv...
Definition avformat.h:982
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:1067
int height
Height of the final image for presentation.
Definition avformat.h:1077
int coded_width
Width of the canvas.
Definition avformat.h:997
unsigned int nb_tiles
Amount of tiles in the grid.
Definition avformat.h:990
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:1041
int horizontal_offset
Offset in pixels from the left edge of the canvas where the actual image meant for presentation start...
Definition avformat.h:1049
const AVClass * av_class
Definition avformat.h:983
int horizontal
Offset in pixels from the left edge of the canvas where the tile should be placed.
Definition avformat.h:1026
unsigned int idx
Index of the stream in the group this tile references.
Definition avformat.h:1021
int vertical_offset
Offset in pixels from the top edge of the canvas where the actual image meant for presentation starts...
Definition avformat.h:1056
int coded_height
Width of the canvas.
Definition avformat.h:1003
int vertical
Offset in pixels from the top edge of the canvas where the tile should be placed.
Definition avformat.h:1031
enum AVStreamGroupParamsType type
Group type.
Definition avformat.h:1117
struct AVIAMFMixPresentation * iamf_mix_presentation
Definition avformat.h:1124
union AVStreamGroup::@4 params
Group type-specific parameters.
struct AVStreamGroupTileGrid * tile_grid
Definition avformat.h:1125
void * priv_data
Definition avformat.h:1096
unsigned int nb_streams
Number of elements in AVStreamGroup.streams.
Definition avformat.h:1143
AVDictionary * metadata
Metadata that applies to the whole group.
Definition avformat.h:1136
unsigned int index
Group index in AVFormatContext.
Definition avformat.h:1101
struct AVIAMFAudioElement * iamf_audio_element
Definition avformat.h:1123
int disposition
Stream group disposition - a combination of AV_DISPOSITION_* flags.
Definition avformat.h:1166
int64_t id
Group type-specific group ID.
Definition avformat.h:1109
AVStream ** streams
A list of streams in the group.
Definition avformat.h:1156
const AVClass * av_class
A class for AVOptions.
Definition avformat.h:1094
Stream structure.
Definition avformat.h:743
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition avformat.h:766
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition avformat.h:821
int64_t nb_frames
number of frames in this stream if known or 0
Definition avformat.h:804
const AVClass * av_class
A class for AVOptions.
Definition avformat.h:747
enum AVDiscard discard
Selects which packets can be discarded at will and do not need to be demuxed.
Definition avformat.h:814
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition avformat.h:802
AVDictionary * metadata
Definition avformat.h:823
void * priv_data
Definition avformat.h:768
int id
Format-specific stream ID.
Definition avformat.h:755
int index
stream index in AVFormatContext
Definition avformat.h:749
int pts_wrap_bits
Number of bits in timestamps.
Definition avformat.h:918
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition avformat.h:792
AVPacket attached_pic
For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet will contain the attached pictu...
Definition avformat.h:841
AVRational avg_frame_rate
Average framerate.
Definition avformat.h:832
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition avformat.h:782
int event_flags
Flags indicating events happening on the stream, a combination of AVSTREAM_EVENT_FLAG_*.
Definition avformat.h:886
AVRational r_frame_rate
Real base framerate of the stream.
Definition avformat.h:909
int disposition
Stream disposition - a combination of AV_DISPOSITION_* flags.
Definition avformat.h:812
static AVStream * ost