2 * copyright (c) 2001 Fabrice Bellard
4 * This file is part of FFmpeg.
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.
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.
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
21 #ifndef AVFORMAT_AVFORMAT_H
22 #define AVFORMAT_AVFORMAT_H
27 * Main libavformat public API header
31 * @defgroup libavf libavformat
32 * I/O and Muxing/Demuxing Library
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().
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.
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).
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).
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.
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.
84 * It is important that the scheme string is not taken from untrusted
85 * sources without checks.
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.
93 * @defgroup lavf_decoding Demuxing
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
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:
106 * const char *url = "file:in.mp3";
107 * AVFormatContext *s = NULL;
108 * int ret = avformat_open_input(&s, url, NULL, NULL);
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.
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.
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:
132 * AVDictionary *options = NULL;
133 * av_dict_set(&options, "video_size", "640x480", 0);
134 * av_dict_set(&options, "pixel_format", "rgb24", 0);
136 * if (avformat_open_input(&s, url, NULL, &options) < 0)
138 * av_dict_free(&options);
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
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);
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.
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.
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.
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
178 * @section lavf_decoding_seek Seeking
181 * @defgroup lavf_encoding Muxing
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.
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.
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:
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
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
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.
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.
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().
241 * @defgroup lavf_io I/O Read/Write
243 * @section lavf_io_dirlist Directory listing
244 * The directory listing API makes it possible to list files on remote servers.
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.
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.
258 * AVIODirContext *ctx = NULL;
259 * if (avio_open_dir(&ctx, "smb://example.com/some_dir", NULL) < 0) {
260 * fprintf(stderr, "Cannot open directory.\n");
265 * This code tries to open a sample directory using smb protocol without
266 * any additional parameters.
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.
278 * AVIODirEntry *entry = NULL;
280 * if (avio_read_dir(ctx, &entry) < 0) {
281 * fprintf(stderr, "Cannot list directory.\n");
286 * printf("%s\n", entry->name);
287 * avio_free_directory_entry(&entry);
292 * @defgroup lavf_codec Demuxers
294 * @defgroup lavf_codec_native Native Demuxers
297 * @defgroup lavf_codec_wrappers External library wrappers
301 * @defgroup lavf_protos I/O Protocols
304 * @defgroup lavf_internal Internal
311 #include <stdio.h> /* FILE */
312 #include "libavcodec/avcodec.h"
313 #include "libavutil/dict.h"
314 #include "libavutil/log.h"
317 #include "libavformat/version.h"
319 struct AVFormatContext;
321 struct AVDeviceInfoList;
322 struct AVDeviceCapabilitiesQuery;
325 * @defgroup metadata_api Public Metadata API
328 * The metadata API allows libavformat to export metadata tags to a client
329 * application when demuxing. Conversely it allows a client application to
330 * set metadata when muxing.
332 * Metadata is exported or set as pairs of key/value strings in the 'metadata'
333 * fields of the AVFormatContext, AVStream, AVChapter and AVProgram structs
334 * using the @ref lavu_dict "AVDictionary" API. Like all strings in FFmpeg,
335 * metadata is assumed to be UTF-8 encoded Unicode. Note that metadata
336 * exported by demuxers isn't checked to be valid UTF-8 in most cases.
338 * Important concepts to keep in mind:
339 * - Keys are unique; there can never be 2 tags with the same key. This is
340 * also meant semantically, i.e., a demuxer should not knowingly produce
341 * several keys that are literally different but semantically identical.
342 * E.g., key=Author5, key=Author6. In this example, all authors must be
343 * placed in the same tag.
344 * - Metadata is flat, not hierarchical; there are no subtags. If you
345 * want to store, e.g., the email address of the child of producer Alice
346 * and actor Bob, that could have key=alice_and_bobs_childs_email_address.
347 * - Several modifiers can be applied to the tag name. This is done by
348 * appending a dash character ('-') and the modifier name in the order
349 * they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng.
350 * - language -- a tag whose value is localized for a particular language
351 * is appended with the ISO 639-2/B 3-letter language code.
352 * For example: Author-ger=Michael, Author-eng=Mike
353 * The original/default language is in the unqualified "Author" tag.
354 * A demuxer should set a default if it sets any translated tag.
355 * - sorting -- a modified version of a tag that should be used for
356 * sorting will have '-sort' appended. E.g. artist="The Beatles",
357 * artist-sort="Beatles, The".
358 * - Some protocols and demuxers support metadata updates. After a successful
359 * call to av_read_frame(), AVFormatContext.event_flags or AVStream.event_flags
360 * will be updated to indicate if metadata changed. In order to detect metadata
361 * changes on a stream, you need to loop through all streams in the AVFormatContext
362 * and check their individual event_flags.
364 * - Demuxers attempt to export metadata in a generic format, however tags
365 * with no generic equivalents are left as they are stored in the container.
366 * Follows a list of generic tag names:
369 album -- name of the set this work belongs to
370 album_artist -- main creator of the set/album, if different from artist.
371 e.g. "Various Artists" for compilation albums.
372 artist -- main creator of the work
373 comment -- any additional description of the file.
374 composer -- who composed the work, if different from artist.
375 copyright -- name of copyright holder.
376 creation_time-- date when the file was created, preferably in ISO 8601.
377 date -- date when the work was created, preferably in ISO 8601.
378 disc -- number of a subset, e.g. disc in a multi-disc collection.
379 encoder -- name/settings of the software/hardware that produced the file.
380 encoded_by -- person/group who created the file.
381 filename -- original name of the file.
382 genre -- <self-evident>.
383 language -- main language in which the work is performed, preferably
384 in ISO 639-2 format. Multiple languages can be specified by
385 separating them with commas.
386 performer -- artist who performed the work, if different from artist.
387 E.g for "Also sprach Zarathustra", artist would be "Richard
388 Strauss" and performer "London Philharmonic Orchestra".
389 publisher -- name of the label/publisher.
390 service_name -- name of the service in broadcasting (channel name).
391 service_provider -- name of the service provider in broadcasting.
392 title -- name of the work.
393 track -- number of this work in the set, can be in form current/total.
394 variant_bitrate -- the total bitrate of the bitrate variant that the current stream is part of
397 * Look in the examples section for an application example how to use the Metadata API.
402 /* packet functions */
406 * Allocate and read the payload of a packet and initialize its
407 * fields with default values.
409 * @param s associated IO context
411 * @param size desired payload size
412 * @return >0 (read size) if OK, AVERROR_xxx otherwise
414 int av_get_packet(AVIOContext *s, AVPacket *pkt, int size);
418 * Read data and append it to the current content of the AVPacket.
419 * If pkt->size is 0 this is identical to av_get_packet.
420 * Note that this uses av_grow_packet and thus involves a realloc
421 * which is inefficient. Thus this function should only be used
422 * when there is no reasonable way to know (an upper bound of)
425 * @param s associated IO context
427 * @param size amount of data to read
428 * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data
429 * will not be lost even if an error occurs.
431 int av_append_packet(AVIOContext *s, AVPacket *pkt, int size);
433 /*************************************************/
434 /* input/output formats */
439 * This structure contains the data a format has to probe a file.
441 typedef struct AVProbeData {
442 const char *filename;
443 unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
444 int buf_size; /**< Size of buf except extra allocated bytes */
445 const char *mime_type; /**< mime_type, when known. */
448 #define AVPROBE_SCORE_RETRY (AVPROBE_SCORE_MAX/4)
449 #define AVPROBE_SCORE_STREAM_RETRY (AVPROBE_SCORE_MAX/4-1)
451 #define AVPROBE_SCORE_EXTENSION 50 ///< score for file extension
452 #define AVPROBE_SCORE_MIME 75 ///< score for file mime type
453 #define AVPROBE_SCORE_MAX 100 ///< maximum score
455 #define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
457 /// Demuxer will use avio_open, no opened file should be provided by the caller.
458 #define AVFMT_NOFILE 0x0001
459 #define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
460 #define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
461 #define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
462 #define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
463 #define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
464 #define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */
465 #define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */
466 #define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */
467 #define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */
468 #define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fall back on binary search via read_timestamp */
469 #define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fall back on generic search */
470 #define AVFMT_NO_BYTE_SEEK 0x8000 /**< Format does not allow seeking by bytes */
471 #define AVFMT_ALLOW_FLUSH 0x10000 /**< Format allows flushing. If not set, the muxer will not receive a NULL packet in the write_packet function. */
472 #define AVFMT_TS_NONSTRICT 0x20000 /**< Format does not require strictly
473 increasing timestamps, but they must
474 still be monotonic */
475 #define AVFMT_TS_NEGATIVE 0x40000 /**< Format allows muxing negative
476 timestamps. If not set the timestamp
477 will be shifted in av_write_frame and
478 av_interleaved_write_frame so they
480 The user or muxer can override this through
481 AVFormatContext.avoid_negative_ts
484 #define AVFMT_SEEK_TO_PTS 0x4000000 /**< Seeking is based on PTS */
487 * @addtogroup lavf_encoding
490 typedef struct AVOutputFormat {
493 * Descriptive name for the format, meant to be more human-readable
494 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
497 const char *long_name;
498 const char *mime_type;
499 const char *extensions; /**< comma-separated filename extensions */
501 enum AVCodecID audio_codec; /**< default audio codec */
502 enum AVCodecID video_codec; /**< default video codec */
503 enum AVCodecID subtitle_codec; /**< default subtitle codec */
505 * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER,
506 * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
507 * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH,
508 * AVFMT_TS_NONSTRICT, AVFMT_TS_NEGATIVE
513 * List of supported codec_id-codec_tag pairs, ordered by "better
514 * choice first". The arrays are all terminated by AV_CODEC_ID_NONE.
516 const struct AVCodecTag * const *codec_tag;
519 const AVClass *priv_class; ///< AVClass for the private context
521 /*****************************************************************
522 * No fields below this line are part of the public API. They
523 * may not be used outside of libavformat and can be changed and
525 * New public fields should be added right above.
526 *****************************************************************
529 * size of private data so that it can be allocated in the wrapper
533 int (*write_header)(struct AVFormatContext *);
535 * Write a packet. If AVFMT_ALLOW_FLUSH is set in flags,
536 * pkt can be NULL in order to flush data buffered in the muxer.
537 * When flushing, return 0 if there still is more data to flush,
538 * or 1 if everything was flushed and there is no more buffered
541 int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
542 int (*write_trailer)(struct AVFormatContext *);
544 * A format-specific function for interleavement.
545 * If unset, packets will be interleaved by dts.
547 int (*interleave_packet)(struct AVFormatContext *, AVPacket *out,
548 AVPacket *in, int flush);
550 * Test if the given codec can be stored in this container.
552 * @return 1 if the codec is supported, 0 if it is not.
553 * A negative number if unknown.
554 * MKTAG('A', 'P', 'I', 'C') if the codec is only supported as AV_DISPOSITION_ATTACHED_PIC
556 int (*query_codec)(enum AVCodecID id, int std_compliance);
558 void (*get_output_timestamp)(struct AVFormatContext *s, int stream,
559 int64_t *dts, int64_t *wall);
561 * Allows sending messages from application to device.
563 int (*control_message)(struct AVFormatContext *s, int type,
564 void *data, size_t data_size);
567 * Write an uncoded AVFrame.
569 * See av_write_uncoded_frame() for details.
571 * The library will free *frame afterwards, but the muxer can prevent it
572 * by setting the pointer to NULL.
574 int (*write_uncoded_frame)(struct AVFormatContext *, int stream_index,
575 AVFrame **frame, unsigned flags);
577 * Returns device list with it properties.
578 * @see avdevice_list_devices() for more details.
580 int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
581 #if LIBAVFORMAT_VERSION_MAJOR < 59
583 * Initialize device capabilities submodule.
584 * @see avdevice_capabilities_create() for more details.
586 int (*create_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
588 * Free device capabilities submodule.
589 * @see avdevice_capabilities_free() for more details.
591 int (*free_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
593 enum AVCodecID data_codec; /**< default data codec */
595 * Initialize format. May allocate data here, and set any AVFormatContext or
596 * AVStream parameters that need to be set before packets are sent.
597 * This method must not write output.
599 * Return 0 if streams were fully configured, 1 if not, negative AVERROR on failure
601 * Any allocations made here must be freed in deinit().
603 int (*init)(struct AVFormatContext *);
605 * Deinitialize format. If present, this is called whenever the muxer is being
606 * destroyed, regardless of whether or not the header has been written.
608 * If a trailer is being written, this is called after write_trailer().
610 * This is called if init() fails as well.
612 void (*deinit)(struct AVFormatContext *);
614 * Set up any necessary bitstream filtering and extract any extra data needed
615 * for the global header.
616 * Return 0 if more packets from this stream must be checked; 1 if not.
618 int (*check_bitstream)(struct AVFormatContext *, const AVPacket *pkt);
625 * @addtogroup lavf_decoding
628 typedef struct AVInputFormat {
630 * A comma separated list of short names for the format. New names
631 * may be appended with a minor bump.
636 * Descriptive name for the format, meant to be more human-readable
637 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
640 const char *long_name;
643 * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
644 * AVFMT_NOTIMESTAMPS, AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
645 * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK, AVFMT_SEEK_TO_PTS.
650 * If extensions are defined, then no probe is done. You should
651 * usually not use extension format guessing because it is not
654 const char *extensions;
656 const struct AVCodecTag * const *codec_tag;
658 const AVClass *priv_class; ///< AVClass for the private context
661 * Comma-separated list of mime types.
662 * It is used check for matching mime types while probing.
663 * @see av_probe_input_format2
665 const char *mime_type;
667 /*****************************************************************
668 * No fields below this line are part of the public API. They
669 * may not be used outside of libavformat and can be changed and
671 * New public fields should be added right above.
672 *****************************************************************
675 * Raw demuxers store their codec ID here.
680 * Size of private data so that it can be allocated in the wrapper.
685 * Tell if a given file has a chance of being parsed as this format.
686 * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
687 * big so you do not have to check for that unless you need more.
689 int (*read_probe)(const AVProbeData *);
692 * Read the format header and initialize the AVFormatContext
693 * structure. Return 0 if OK. 'avformat_new_stream' should be
694 * called to create new streams.
696 int (*read_header)(struct AVFormatContext *);
699 * Read one packet and put it in 'pkt'. pts and flags are also
700 * set. 'avformat_new_stream' can be called only if the flag
701 * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
702 * background thread).
703 * @return 0 on success, < 0 on error.
704 * Upon returning an error, pkt must be unreferenced by the caller.
706 int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
709 * Close the stream. The AVFormatContext and AVStreams are not
710 * freed by this function
712 int (*read_close)(struct AVFormatContext *);
715 * Seek to a given timestamp relative to the frames in
716 * stream component stream_index.
717 * @param stream_index Must not be -1.
718 * @param flags Selects which direction should be preferred if no exact
719 * match is available.
720 * @return >= 0 on success (but not necessarily the new offset)
722 int (*read_seek)(struct AVFormatContext *,
723 int stream_index, int64_t timestamp, int flags);
726 * Get the next timestamp in stream[stream_index].time_base units.
727 * @return the timestamp or AV_NOPTS_VALUE if an error occurred
729 int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
730 int64_t *pos, int64_t pos_limit);
733 * Start/resume playing - only meaningful if using a network-based format
736 int (*read_play)(struct AVFormatContext *);
739 * Pause playing - only meaningful if using a network-based format
742 int (*read_pause)(struct AVFormatContext *);
745 * Seek to timestamp ts.
746 * Seeking will be done so that the point from which all active streams
747 * can be presented successfully will be closest to ts and within min/max_ts.
748 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
750 int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
753 * Returns device list with it properties.
754 * @see avdevice_list_devices() for more details.
756 int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
758 #if LIBAVFORMAT_VERSION_MAJOR < 59
760 * Initialize device capabilities submodule.
761 * @see avdevice_capabilities_create() for more details.
763 int (*create_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
766 * Free device capabilities submodule.
767 * @see avdevice_capabilities_free() for more details.
769 int (*free_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
776 enum AVStreamParseType {
778 AVSTREAM_PARSE_FULL, /**< full parsing and repack */
779 AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
780 AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
781 AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
782 AVSTREAM_PARSE_FULL_RAW, /**< full parsing and repack with timestamp and position generation by parser for raw
783 this assumes that each packet in the file contains no demuxer level headers and
784 just codec level data, otherwise position generation would fail */
787 typedef struct AVIndexEntry {
789 int64_t timestamp; /**<
790 * Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are available
791 * when seeking to this entry. That means preferable PTS on keyframe based formats.
792 * But demuxers can choose to store a different timestamp, if it is more convenient for the implementation or nothing better
795 #define AVINDEX_KEYFRAME 0x0001
796 #define AVINDEX_DISCARD_FRAME 0x0002 /**
797 * Flag is used to indicate which frame should be discarded after decoding.
800 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).
801 int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
804 #define AV_DISPOSITION_DEFAULT 0x0001
805 #define AV_DISPOSITION_DUB 0x0002
806 #define AV_DISPOSITION_ORIGINAL 0x0004
807 #define AV_DISPOSITION_COMMENT 0x0008
808 #define AV_DISPOSITION_LYRICS 0x0010
809 #define AV_DISPOSITION_KARAOKE 0x0020
812 * Track should be used during playback by default.
813 * Useful for subtitle track that should be displayed
814 * even when user did not explicitly ask for subtitles.
816 #define AV_DISPOSITION_FORCED 0x0040
817 #define AV_DISPOSITION_HEARING_IMPAIRED 0x0080 /**< stream for hearing impaired audiences */
818 #define AV_DISPOSITION_VISUAL_IMPAIRED 0x0100 /**< stream for visual impaired audiences */
819 #define AV_DISPOSITION_CLEAN_EFFECTS 0x0200 /**< stream without voice */
821 * The stream is stored in the file as an attached picture/"cover art" (e.g.
822 * APIC frame in ID3v2). The first (usually only) packet associated with it
823 * will be returned among the first few packets read from the file unless
824 * seeking takes place. It can also be accessed at any time in
825 * AVStream.attached_pic.
827 #define AV_DISPOSITION_ATTACHED_PIC 0x0400
829 * The stream is sparse, and contains thumbnail images, often corresponding
830 * to chapter markers. Only ever used with AV_DISPOSITION_ATTACHED_PIC.
832 #define AV_DISPOSITION_TIMED_THUMBNAILS 0x0800
834 typedef struct AVStreamInternal AVStreamInternal;
837 * To specify text track kind (different from subtitles default).
839 #define AV_DISPOSITION_CAPTIONS 0x10000
840 #define AV_DISPOSITION_DESCRIPTIONS 0x20000
841 #define AV_DISPOSITION_METADATA 0x40000
842 #define AV_DISPOSITION_DEPENDENT 0x80000 ///< dependent audio stream (mix_type=0 in mpegts)
843 #define AV_DISPOSITION_STILL_IMAGE 0x100000 ///< still images in video stream (still_picture_flag=1 in mpegts)
846 * Options for behavior on timestamp wrap detection.
848 #define AV_PTS_WRAP_IGNORE 0 ///< ignore the wrap
849 #define AV_PTS_WRAP_ADD_OFFSET 1 ///< add the format specific offset on wrap detection
850 #define AV_PTS_WRAP_SUB_OFFSET -1 ///< subtract the format specific offset on wrap detection
854 * New fields can be added to the end with minor version bumps.
855 * Removal, reordering and changes to existing fields require a major
857 * sizeof(AVStream) must not be used outside libav*.
859 typedef struct AVStream {
860 int index; /**< stream index in AVFormatContext */
862 * Format-specific stream ID.
863 * decoding: set by libavformat
864 * encoding: set by the user, replaced by libavformat if left unset
867 #if FF_API_LAVF_AVCTX
869 * @deprecated use the codecpar struct instead
872 AVCodecContext *codec;
877 * This is the fundamental unit of time (in seconds) in terms
878 * of which frame timestamps are represented.
880 * decoding: set by libavformat
881 * encoding: May be set by the caller before avformat_write_header() to
882 * provide a hint to the muxer about the desired timebase. In
883 * avformat_write_header(), the muxer will overwrite this field
884 * with the timebase that will actually be used for the timestamps
885 * written into the file (which may or may not be related to the
886 * user-provided one, depending on the format).
888 AVRational time_base;
891 * Decoding: pts of the first frame of the stream in presentation order, in stream time base.
892 * Only set this if you are absolutely 100% sure that the value you set
893 * it to really is the pts of the first frame.
894 * This may be undefined (AV_NOPTS_VALUE).
895 * @note The ASF header does NOT contain a correct start_time the ASF
896 * demuxer must NOT set this.
901 * Decoding: duration of the stream, in stream time base.
902 * If a source file does not specify a duration, but does specify
903 * a bitrate, this value will be estimated from bitrate and file size.
905 * Encoding: May be set by the caller before avformat_write_header() to
906 * provide a hint to the muxer about the estimated duration.
910 int64_t nb_frames; ///< number of frames in this stream if known or 0
912 int disposition; /**< AV_DISPOSITION_* bit field */
914 enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
917 * sample aspect ratio (0 if unknown)
918 * - encoding: Set by user.
919 * - decoding: Set by libavformat.
921 AVRational sample_aspect_ratio;
923 AVDictionary *metadata;
928 * - demuxing: May be set by libavformat when creating the stream or in
929 * avformat_find_stream_info().
930 * - muxing: May be set by the caller before avformat_write_header().
932 AVRational avg_frame_rate;
935 * For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet
936 * will contain the attached picture.
938 * decoding: set by libavformat, must not be modified by the caller.
941 AVPacket attached_pic;
944 * An array of side data that applies to the whole stream (i.e. the
945 * container does not allow it to change between packets).
947 * There may be no overlap between the side data in this array and side data
948 * in the packets. I.e. a given side data is either exported by the muxer
949 * (demuxing) / set by the caller (muxing) in this array, then it never
950 * appears in the packets, or the side data is exported / sent through
951 * the packets (always in the first packet where the value becomes known or
952 * changes), then it does not appear in this array.
954 * - demuxing: Set by libavformat when the stream is created.
955 * - muxing: May be set by the caller before avformat_write_header().
957 * Freed by libavformat in avformat_free_context().
959 * @see av_format_inject_global_side_data()
961 AVPacketSideData *side_data;
963 * The number of elements in the AVStream.side_data array.
968 * Flags indicating events happening on the stream, a combination of
969 * AVSTREAM_EVENT_FLAG_*.
971 * - demuxing: may be set by the demuxer in avformat_open_input(),
972 * avformat_find_stream_info() and av_read_frame(). Flags must be cleared
973 * by the user once the event has been handled.
974 * - muxing: may be set by the user after avformat_write_header(). to
975 * indicate a user-triggered event. The muxer will clear the flags for
976 * events it has handled in av_[interleaved]_write_frame().
980 * - demuxing: the demuxer read new metadata from the file and updated
981 * AVStream.metadata accordingly
982 * - muxing: the user updated AVStream.metadata and wishes the muxer to write
985 #define AVSTREAM_EVENT_FLAG_METADATA_UPDATED 0x0001
987 * - demuxing: new packets for this stream were read from the file. This
988 * event is informational only and does not guarantee that new packets
989 * for this stream will necessarily be returned from av_read_frame().
991 #define AVSTREAM_EVENT_FLAG_NEW_PACKETS (1 << 1)
994 * Real base framerate of the stream.
995 * This is the lowest framerate with which all timestamps can be
996 * represented accurately (it is the least common multiple of all
997 * framerates in the stream). Note, this value is just a guess!
998 * For example, if the time base is 1/90000 and all frames have either
999 * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
1001 AVRational r_frame_rate;
1003 #if FF_API_LAVF_FFSERVER
1005 * String containing pairs of key and values describing recommended encoder configuration.
1006 * Pairs are separated by ','.
1007 * Keys are separated from values by '='.
1009 * @deprecated unused
1011 attribute_deprecated
1012 char *recommended_encoder_configuration;
1016 * Codec parameters associated with this stream. Allocated and freed by
1017 * libavformat in avformat_new_stream() and avformat_free_context()
1020 * - demuxing: filled by libavformat on stream creation or in
1021 * avformat_find_stream_info()
1022 * - muxing: filled by the caller before avformat_write_header()
1024 AVCodecParameters *codecpar;
1026 /*****************************************************************
1027 * All fields below this line are not part of the public API. They
1028 * may not be used outside of libavformat and can be changed and
1030 * Internal note: be aware that physically removing these fields
1031 * will break ABI. Replace removed fields with dummy fields, and
1032 * add new fields to AVStreamInternal.
1033 *****************************************************************
1036 #if LIBAVFORMAT_VERSION_MAJOR < 59
1037 // kept for ABI compatibility only, do not access in any way
1041 int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
1043 // Timestamp generation support:
1045 * Timestamp corresponding to the last dts sync point.
1047 * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
1048 * a DTS is received from the underlying container. Otherwise set to
1049 * AV_NOPTS_VALUE by default.
1053 int64_t last_IP_pts;
1054 int last_IP_duration;
1057 * Number of packets to buffer for codec probing
1062 * Number of frames that have been demuxed during avformat_find_stream_info()
1064 int codec_info_nb_frames;
1066 /* av_read_frame() support */
1067 enum AVStreamParseType need_parsing;
1068 struct AVCodecParserContext *parser;
1070 #if LIBAVFORMAT_VERSION_MAJOR < 59
1071 // kept for ABI compatibility only, do not access in any way
1073 AVProbeData unused6;
1074 int64_t unused5[16+1];
1077 unsigned int unused4;
1082 * This is the MPEG-TS stream identifier +1
1085 int stream_identifier;
1087 #if LIBAVFORMAT_VERSION_MAJOR < 59
1088 // kept for ABI compatibility only, do not access in any way
1095 * An opaque field for libavformat internal usage.
1096 * Must not be accessed in any way by callers.
1098 AVStreamInternal *internal;
1101 #if FF_API_FORMAT_GET_SET
1103 * Accessors for some AVStream fields. These used to be provided for ABI
1104 * compatibility, and do not need to be used anymore.
1106 attribute_deprecated
1107 AVRational av_stream_get_r_frame_rate(const AVStream *s);
1108 attribute_deprecated
1109 void av_stream_set_r_frame_rate(AVStream *s, AVRational r);
1110 #if FF_API_LAVF_FFSERVER
1111 attribute_deprecated
1112 char* av_stream_get_recommended_encoder_configuration(const AVStream *s);
1113 attribute_deprecated
1114 void av_stream_set_recommended_encoder_configuration(AVStream *s, char *configuration);
1118 struct AVCodecParserContext *av_stream_get_parser(const AVStream *s);
1121 * Returns the pts of the last muxed packet + its duration
1123 * the retuned value is undefined when used with a demuxer.
1125 int64_t av_stream_get_end_pts(const AVStream *st);
1127 #define AV_PROGRAM_RUNNING 1
1130 * New fields can be added to the end with minor version bumps.
1131 * Removal, reordering and changes to existing fields require a major
1133 * sizeof(AVProgram) must not be used outside libav*.
1135 typedef struct AVProgram {
1138 enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
1139 unsigned int *stream_index;
1140 unsigned int nb_stream_indexes;
1141 AVDictionary *metadata;
1148 /*****************************************************************
1149 * All fields below this line are not part of the public API. They
1150 * may not be used outside of libavformat and can be changed and
1152 * New public fields should be added right above.
1153 *****************************************************************
1158 int64_t pts_wrap_reference; ///< reference dts for wrap detection
1159 int pts_wrap_behavior; ///< behavior on wrap detection
1162 #define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
1163 (streams are added dynamically) */
1164 #define AVFMTCTX_UNSEEKABLE 0x0002 /**< signal that the stream is definitely
1165 not seekable, and attempts to call the
1166 seek function will fail. For some
1167 network protocols (e.g. HLS), this can
1168 change dynamically at runtime. */
1170 typedef struct AVChapter {
1171 #if FF_API_CHAPTER_ID_INT
1172 int id; ///< unique ID to identify the chapter
1174 int64_t id; ///< unique ID to identify the chapter
1176 AVRational time_base; ///< time base in which the start/end timestamps are specified
1177 int64_t start, end; ///< chapter start/end time in time_base units
1178 AVDictionary *metadata;
1183 * Callback used by devices to communicate with application.
1185 typedef int (*av_format_control_message)(struct AVFormatContext *s, int type,
1186 void *data, size_t data_size);
1188 typedef int (*AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags,
1189 const AVIOInterruptCB *int_cb, AVDictionary **options);
1192 * The duration of a video can be estimated through various ways, and this enum can be used
1193 * to know how the duration was estimated.
1195 enum AVDurationEstimationMethod {
1196 AVFMT_DURATION_FROM_PTS, ///< Duration accurately estimated from PTSes
1197 AVFMT_DURATION_FROM_STREAM, ///< Duration estimated from a stream with a known duration
1198 AVFMT_DURATION_FROM_BITRATE ///< Duration estimated from bitrate (less accurate)
1201 typedef struct AVFormatInternal AVFormatInternal;
1204 * Format I/O context.
1205 * New fields can be added to the end with minor version bumps.
1206 * Removal, reordering and changes to existing fields require a major
1208 * sizeof(AVFormatContext) must not be used outside libav*, use
1209 * avformat_alloc_context() to create an AVFormatContext.
1211 * Fields can be accessed through AVOptions (av_opt*),
1212 * the name string used matches the associated command line parameter name and
1213 * can be found in libavformat/options_table.h.
1214 * The AVOption/command line parameter names differ in some cases from the C
1215 * structure field names for historic reasons or brevity.
1217 typedef struct AVFormatContext {
1219 * A class for logging and @ref avoptions. Set by avformat_alloc_context().
1220 * Exports (de)muxer private options if they exist.
1222 const AVClass *av_class;
1225 * The input container format.
1227 * Demuxing only, set by avformat_open_input().
1229 const struct AVInputFormat *iformat;
1232 * The output container format.
1234 * Muxing only, must be set by the caller before avformat_write_header().
1236 const struct AVOutputFormat *oformat;
1239 * Format private data. This is an AVOptions-enabled struct
1240 * if and only if iformat/oformat.priv_class is not NULL.
1242 * - muxing: set by avformat_write_header()
1243 * - demuxing: set by avformat_open_input()
1250 * - demuxing: either set by the user before avformat_open_input() (then
1251 * the user must close it manually) or set by avformat_open_input().
1252 * - muxing: set by the user before avformat_write_header(). The caller must
1253 * take care of closing / freeing the IO context.
1255 * Do NOT set this field if AVFMT_NOFILE flag is set in
1256 * iformat/oformat.flags. In such a case, the (de)muxer will handle
1257 * I/O in some other way and this field will be NULL.
1263 * Flags signalling stream properties. A combination of AVFMTCTX_*.
1264 * Set by libavformat.
1269 * Number of elements in AVFormatContext.streams.
1271 * Set by avformat_new_stream(), must not be modified by any other code.
1273 unsigned int nb_streams;
1275 * A list of all streams in the file. New streams are created with
1276 * avformat_new_stream().
1278 * - demuxing: streams are created by libavformat in avformat_open_input().
1279 * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
1280 * appear in av_read_frame().
1281 * - muxing: streams are created by the user before avformat_write_header().
1283 * Freed by libavformat in avformat_free_context().
1287 #if FF_API_FORMAT_FILENAME
1289 * input or output filename
1291 * - demuxing: set by avformat_open_input()
1292 * - muxing: may be set by the caller before avformat_write_header()
1294 * @deprecated Use url instead.
1296 attribute_deprecated
1297 char filename[1024];
1301 * input or output URL. Unlike the old filename field, this field has no
1302 * length restriction.
1304 * - demuxing: set by avformat_open_input(), initialized to an empty
1305 * string if url parameter was NULL in avformat_open_input().
1306 * - muxing: may be set by the caller before calling avformat_write_header()
1307 * (or avformat_init_output() if that is called first) to a string
1308 * which is freeable by av_free(). Set to an empty string if it
1309 * was NULL in avformat_init_output().
1311 * Freed by libavformat in avformat_free_context().
1316 * Position of the first frame of the component, in
1317 * AV_TIME_BASE fractional seconds. NEVER set this value directly:
1318 * It is deduced from the AVStream values.
1320 * Demuxing only, set by libavformat.
1325 * Duration of the stream, in AV_TIME_BASE fractional
1326 * seconds. Only set this value if you know none of the individual stream
1327 * durations and also do not set any of them. This is deduced from the
1328 * AVStream values if not set.
1330 * Demuxing only, set by libavformat.
1335 * Total stream bitrate in bit/s, 0 if not
1336 * available. Never set it directly if the file_size and the
1337 * duration are known as FFmpeg can compute it automatically.
1341 unsigned int packet_size;
1345 * Flags modifying the (de)muxer behaviour. A combination of AVFMT_FLAG_*.
1346 * Set by the user before avformat_open_input() / avformat_write_header().
1349 #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
1350 #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
1351 #define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
1352 #define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
1353 #define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
1354 #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
1355 #define AVFMT_FLAG_NOBUFFER 0x0040 ///< Do not buffer frames when possible
1356 #define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
1357 #define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted
1358 #define AVFMT_FLAG_FLUSH_PACKETS 0x0200 ///< Flush the AVIOContext every packet.
1360 * When muxing, try to avoid writing any random/volatile data to the output.
1361 * This includes any random IDs, real-time timestamps/dates, muxer version, etc.
1363 * This flag is mainly intended for testing.
1365 #define AVFMT_FLAG_BITEXACT 0x0400
1366 #if FF_API_LAVF_MP4A_LATM
1367 #define AVFMT_FLAG_MP4A_LATM 0x8000 ///< Deprecated, does nothing.
1369 #define AVFMT_FLAG_SORT_DTS 0x10000 ///< try to interleave outputted packets by dts (using this flag can slow demuxing down)
1370 #if FF_API_LAVF_PRIV_OPT
1371 #define AVFMT_FLAG_PRIV_OPT 0x20000 ///< Enable use of private options by delaying codec open (deprecated, will do nothing once av_demuxer_open() is removed)
1373 #if FF_API_LAVF_KEEPSIDE_FLAG
1374 #define AVFMT_FLAG_KEEP_SIDE_DATA 0x40000 ///< Deprecated, does nothing.
1376 #define AVFMT_FLAG_FAST_SEEK 0x80000 ///< Enable fast, but inaccurate seeks for some formats
1377 #define AVFMT_FLAG_SHORTEST 0x100000 ///< Stop muxing when the shortest stream stops.
1378 #define AVFMT_FLAG_AUTO_BSF 0x200000 ///< Add bitstream filters as requested by the muxer
1381 * Maximum size of the data read from input for determining
1382 * the input container format.
1383 * Demuxing only, set by the caller before avformat_open_input().
1388 * Maximum duration (in AV_TIME_BASE units) of the data read
1389 * from input in avformat_find_stream_info().
1390 * Demuxing only, set by the caller before avformat_find_stream_info().
1391 * Can be set to 0 to let avformat choose using a heuristic.
1393 int64_t max_analyze_duration;
1398 unsigned int nb_programs;
1399 AVProgram **programs;
1402 * Forced video codec_id.
1403 * Demuxing: Set by user.
1405 enum AVCodecID video_codec_id;
1408 * Forced audio codec_id.
1409 * Demuxing: Set by user.
1411 enum AVCodecID audio_codec_id;
1414 * Forced subtitle codec_id.
1415 * Demuxing: Set by user.
1417 enum AVCodecID subtitle_codec_id;
1420 * Maximum amount of memory in bytes to use for the index of each stream.
1421 * If the index exceeds this size, entries will be discarded as
1422 * needed to maintain a smaller size. This can lead to slower or less
1423 * accurate seeking (depends on demuxer).
1424 * Demuxers for which a full in-memory index is mandatory will ignore
1427 * - demuxing: set by user
1429 unsigned int max_index_size;
1432 * Maximum amount of memory in bytes to use for buffering frames
1433 * obtained from realtime capture devices.
1435 unsigned int max_picture_buffer;
1438 * Number of chapters in AVChapter array.
1439 * When muxing, chapters are normally written in the file header,
1440 * so nb_chapters should normally be initialized before write_header
1441 * is called. Some muxers (e.g. mov and mkv) can also write chapters
1442 * in the trailer. To write chapters in the trailer, nb_chapters
1443 * must be zero when write_header is called and non-zero when
1444 * write_trailer is called.
1445 * - muxing: set by user
1446 * - demuxing: set by libavformat
1448 unsigned int nb_chapters;
1449 AVChapter **chapters;
1452 * Metadata that applies to the whole file.
1454 * - demuxing: set by libavformat in avformat_open_input()
1455 * - muxing: may be set by the caller before avformat_write_header()
1457 * Freed by libavformat in avformat_free_context().
1459 AVDictionary *metadata;
1462 * Start time of the stream in real world time, in microseconds
1463 * since the Unix epoch (00:00 1st January 1970). That is, pts=0 in the
1464 * stream was captured at this real world time.
1465 * - muxing: Set by the caller before avformat_write_header(). If set to
1466 * either 0 or AV_NOPTS_VALUE, then the current wall-time will
1468 * - demuxing: Set by libavformat. AV_NOPTS_VALUE if unknown. Note that
1469 * the value may become known after some number of frames
1470 * have been received.
1472 int64_t start_time_realtime;
1475 * The number of frames used for determining the framerate in
1476 * avformat_find_stream_info().
1477 * Demuxing only, set by the caller before avformat_find_stream_info().
1482 * Error recognition; higher values will detect more errors but may
1483 * misdetect some more or less valid parts as errors.
1484 * Demuxing only, set by the caller before avformat_open_input().
1486 int error_recognition;
1489 * Custom interrupt callbacks for the I/O layer.
1491 * demuxing: set by the user before avformat_open_input().
1492 * muxing: set by the user before avformat_write_header()
1493 * (mainly useful for AVFMT_NOFILE formats). The callback
1494 * should also be passed to avio_open2() if it's used to
1497 AVIOInterruptCB interrupt_callback;
1500 * Flags to enable debugging.
1503 #define FF_FDEBUG_TS 0x0001
1506 * Maximum buffering duration for interleaving.
1508 * To ensure all the streams are interleaved correctly,
1509 * av_interleaved_write_frame() will wait until it has at least one packet
1510 * for each stream before actually writing any packets to the output file.
1511 * When some streams are "sparse" (i.e. there are large gaps between
1512 * successive packets), this can result in excessive buffering.
1514 * This field specifies the maximum difference between the timestamps of the
1515 * first and the last packet in the muxing queue, above which libavformat
1516 * will output a packet regardless of whether it has queued a packet for all
1519 * Muxing only, set by the caller before avformat_write_header().
1521 int64_t max_interleave_delta;
1524 * Allow non-standard and experimental extension
1525 * @see AVCodecContext.strict_std_compliance
1527 int strict_std_compliance;
1530 * Flags indicating events happening on the file, a combination of
1531 * AVFMT_EVENT_FLAG_*.
1533 * - demuxing: may be set by the demuxer in avformat_open_input(),
1534 * avformat_find_stream_info() and av_read_frame(). Flags must be cleared
1535 * by the user once the event has been handled.
1536 * - muxing: may be set by the user after avformat_write_header() to
1537 * indicate a user-triggered event. The muxer will clear the flags for
1538 * events it has handled in av_[interleaved]_write_frame().
1542 * - demuxing: the demuxer read new metadata from the file and updated
1543 * AVFormatContext.metadata accordingly
1544 * - muxing: the user updated AVFormatContext.metadata and wishes the muxer to
1545 * write it into the file
1547 #define AVFMT_EVENT_FLAG_METADATA_UPDATED 0x0001
1550 * Maximum number of packets to read while waiting for the first timestamp.
1556 * Avoid negative timestamps during muxing.
1557 * Any value of the AVFMT_AVOID_NEG_TS_* constants.
1558 * Note, this only works when using av_interleaved_write_frame. (interleave_packet_per_dts is in use)
1559 * - muxing: Set by user
1560 * - demuxing: unused
1562 int avoid_negative_ts;
1563 #define AVFMT_AVOID_NEG_TS_AUTO -1 ///< Enabled when required by target format
1564 #define AVFMT_AVOID_NEG_TS_MAKE_NON_NEGATIVE 1 ///< Shift timestamps so they are non negative
1565 #define AVFMT_AVOID_NEG_TS_MAKE_ZERO 2 ///< Shift timestamps so that they start at 0
1568 * Transport stream id.
1569 * This will be moved into demuxer private options. Thus no API/ABI compatibility
1574 * Audio preload in microseconds.
1575 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1576 * - encoding: Set by user
1577 * - decoding: unused
1582 * Max chunk time in microseconds.
1583 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1584 * - encoding: Set by user
1585 * - decoding: unused
1587 int max_chunk_duration;
1590 * Max chunk size in bytes
1591 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1592 * - encoding: Set by user
1593 * - decoding: unused
1598 * forces the use of wallclock timestamps as pts/dts of packets
1599 * This has undefined results in the presence of B frames.
1600 * - encoding: unused
1601 * - decoding: Set by user
1603 int use_wallclock_as_timestamps;
1606 * avio flags, used to force AVIO_FLAG_DIRECT.
1607 * - encoding: unused
1608 * - decoding: Set by user
1613 * The duration field can be estimated through various ways, and this field can be used
1614 * to know how the duration was estimated.
1615 * - encoding: unused
1616 * - decoding: Read by user
1618 enum AVDurationEstimationMethod duration_estimation_method;
1621 * Skip initial bytes when opening stream
1622 * - encoding: unused
1623 * - decoding: Set by user
1625 int64_t skip_initial_bytes;
1628 * Correct single timestamp overflows
1629 * - encoding: unused
1630 * - decoding: Set by user
1632 unsigned int correct_ts_overflow;
1635 * Force seeking to any (also non key) frames.
1636 * - encoding: unused
1637 * - decoding: Set by user
1642 * Flush the I/O context after each packet.
1643 * - encoding: Set by user
1644 * - decoding: unused
1649 * format probing score.
1650 * The maximal score is AVPROBE_SCORE_MAX, its set when the demuxer probes
1652 * - encoding: unused
1653 * - decoding: set by avformat, read by user
1658 * number of bytes to read maximally to identify format.
1659 * - encoding: unused
1660 * - decoding: set by user
1662 int format_probesize;
1665 * ',' separated list of allowed decoders.
1666 * If NULL then all are allowed
1667 * - encoding: unused
1668 * - decoding: set by user
1670 char *codec_whitelist;
1673 * ',' separated list of allowed demuxers.
1674 * If NULL then all are allowed
1675 * - encoding: unused
1676 * - decoding: set by user
1678 char *format_whitelist;
1681 * An opaque field for libavformat internal usage.
1682 * Must not be accessed in any way by callers.
1684 AVFormatInternal *internal;
1687 * IO repositioned flag.
1688 * This is set by avformat when the underlaying IO context read pointer
1689 * is repositioned, for example when doing byte based seeking.
1690 * Demuxers can use the flag to detect such changes.
1692 int io_repositioned;
1695 * Forced video codec.
1696 * This allows forcing a specific decoder, even when there are multiple with
1697 * the same codec_id.
1698 * Demuxing: Set by user
1700 AVCodec *video_codec;
1703 * Forced audio codec.
1704 * This allows forcing a specific decoder, even when there are multiple with
1705 * the same codec_id.
1706 * Demuxing: Set by user
1708 AVCodec *audio_codec;
1711 * Forced subtitle codec.
1712 * This allows forcing a specific decoder, even when there are multiple with
1713 * the same codec_id.
1714 * Demuxing: Set by user
1716 AVCodec *subtitle_codec;
1719 * Forced data codec.
1720 * This allows forcing a specific decoder, even when there are multiple with
1721 * the same codec_id.
1722 * Demuxing: Set by user
1724 AVCodec *data_codec;
1727 * Number of bytes to be written as padding in a metadata header.
1729 * Muxing: Set by user via av_format_set_metadata_header_padding.
1731 int metadata_header_padding;
1735 * This is a place for some private data of the user.
1740 * Callback used by devices to communicate with application.
1742 av_format_control_message control_message_cb;
1745 * Output timestamp offset, in microseconds.
1746 * Muxing: set by user
1748 int64_t output_ts_offset;
1751 * dump format separator.
1752 * can be ", " or "\n " or anything else
1753 * - muxing: Set by user.
1754 * - demuxing: Set by user.
1756 uint8_t *dump_separator;
1759 * Forced Data codec_id.
1760 * Demuxing: Set by user.
1762 enum AVCodecID data_codec_id;
1764 #if FF_API_OLD_OPEN_CALLBACKS
1766 * Called to open further IO contexts when needed for demuxing.
1768 * This can be set by the user application to perform security checks on
1769 * the URLs before opening them.
1770 * The function should behave like avio_open2(), AVFormatContext is provided
1771 * as contextual information and to reach AVFormatContext.opaque.
1773 * If NULL then some simple checks are used together with avio_open2().
1775 * Must not be accessed directly from outside avformat.
1776 * @See av_format_set_open_cb()
1778 * Demuxing: Set by user.
1780 * @deprecated Use io_open and io_close.
1782 attribute_deprecated
1783 int (*open_cb)(struct AVFormatContext *s, AVIOContext **p, const char *url, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options);
1787 * ',' separated list of allowed protocols.
1788 * - encoding: unused
1789 * - decoding: set by user
1791 char *protocol_whitelist;
1794 * A callback for opening new IO streams.
1796 * Whenever a muxer or a demuxer needs to open an IO stream (typically from
1797 * avformat_open_input() for demuxers, but for certain formats can happen at
1798 * other times as well), it will call this callback to obtain an IO context.
1800 * @param s the format context
1801 * @param pb on success, the newly opened IO context should be returned here
1802 * @param url the url to open
1803 * @param flags a combination of AVIO_FLAG_*
1804 * @param options a dictionary of additional options, with the same
1805 * semantics as in avio_open2()
1806 * @return 0 on success, a negative AVERROR code on failure
1808 * @note Certain muxers and demuxers do nesting, i.e. they open one or more
1809 * additional internal format contexts. Thus the AVFormatContext pointer
1810 * passed to this callback may be different from the one facing the caller.
1811 * It will, however, have the same 'opaque' field.
1813 int (*io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url,
1814 int flags, AVDictionary **options);
1817 * A callback for closing the streams opened with AVFormatContext.io_open().
1819 void (*io_close)(struct AVFormatContext *s, AVIOContext *pb);
1822 * ',' separated list of disallowed protocols.
1823 * - encoding: unused
1824 * - decoding: set by user
1826 char *protocol_blacklist;
1829 * The maximum number of streams.
1830 * - encoding: unused
1831 * - decoding: set by user
1836 * Skip duration calcuation in estimate_timings_from_pts.
1837 * - encoding: unused
1838 * - decoding: set by user
1840 int skip_estimate_duration_from_pts;
1843 * Maximum number of packets that can be probed
1844 * - encoding: unused
1845 * - decoding: set by user
1847 int max_probe_packets;
1850 #if FF_API_FORMAT_GET_SET
1852 * Accessors for some AVFormatContext fields. These used to be provided for ABI
1853 * compatibility, and do not need to be used anymore.
1855 attribute_deprecated
1856 int av_format_get_probe_score(const AVFormatContext *s);
1857 attribute_deprecated
1858 AVCodec * av_format_get_video_codec(const AVFormatContext *s);
1859 attribute_deprecated
1860 void av_format_set_video_codec(AVFormatContext *s, AVCodec *c);
1861 attribute_deprecated
1862 AVCodec * av_format_get_audio_codec(const AVFormatContext *s);
1863 attribute_deprecated
1864 void av_format_set_audio_codec(AVFormatContext *s, AVCodec *c);
1865 attribute_deprecated
1866 AVCodec * av_format_get_subtitle_codec(const AVFormatContext *s);
1867 attribute_deprecated
1868 void av_format_set_subtitle_codec(AVFormatContext *s, AVCodec *c);
1869 attribute_deprecated
1870 AVCodec * av_format_get_data_codec(const AVFormatContext *s);
1871 attribute_deprecated
1872 void av_format_set_data_codec(AVFormatContext *s, AVCodec *c);
1873 attribute_deprecated
1874 int av_format_get_metadata_header_padding(const AVFormatContext *s);
1875 attribute_deprecated
1876 void av_format_set_metadata_header_padding(AVFormatContext *s, int c);
1877 attribute_deprecated
1878 void * av_format_get_opaque(const AVFormatContext *s);
1879 attribute_deprecated
1880 void av_format_set_opaque(AVFormatContext *s, void *opaque);
1881 attribute_deprecated
1882 av_format_control_message av_format_get_control_message_cb(const AVFormatContext *s);
1883 attribute_deprecated
1884 void av_format_set_control_message_cb(AVFormatContext *s, av_format_control_message callback);
1885 #if FF_API_OLD_OPEN_CALLBACKS
1886 attribute_deprecated AVOpenCallback av_format_get_open_cb(const AVFormatContext *s);
1887 attribute_deprecated void av_format_set_open_cb(AVFormatContext *s, AVOpenCallback callback);
1892 * This function will cause global side data to be injected in the next packet
1893 * of each stream as well as after any subsequent seek.
1895 void av_format_inject_global_side_data(AVFormatContext *s);
1898 * Returns the method used to set ctx->duration.
1900 * @return AVFMT_DURATION_FROM_PTS, AVFMT_DURATION_FROM_STREAM, or AVFMT_DURATION_FROM_BITRATE.
1902 enum AVDurationEstimationMethod av_fmt_ctx_get_duration_estimation_method(const AVFormatContext* ctx);
1905 * @defgroup lavf_core Core functions
1908 * Functions for querying libavformat capabilities, allocating core structures,
1914 * Return the LIBAVFORMAT_VERSION_INT constant.
1916 unsigned avformat_version(void);
1919 * Return the libavformat build-time configuration.
1921 const char *avformat_configuration(void);
1924 * Return the libavformat license.
1926 const char *avformat_license(void);
1929 * Do global initialization of network libraries. This is optional,
1930 * and not recommended anymore.
1932 * This functions only exists to work around thread-safety issues
1933 * with older GnuTLS or OpenSSL libraries. If libavformat is linked
1934 * to newer versions of those libraries, or if you do not use them,
1935 * calling this function is unnecessary. Otherwise, you need to call
1936 * this function before any other threads using them are started.
1938 * This function will be deprecated once support for older GnuTLS and
1939 * OpenSSL libraries is removed, and this function has no purpose
1942 int avformat_network_init(void);
1945 * Undo the initialization done by avformat_network_init. Call it only
1946 * once for each time you called avformat_network_init.
1948 int avformat_network_deinit(void);
1951 * Iterate over all registered muxers.
1953 * @param opaque a pointer where libavformat will store the iteration state. Must
1954 * point to NULL to start the iteration.
1956 * @return the next registered muxer or NULL when the iteration is
1959 const AVOutputFormat *av_muxer_iterate(void **opaque);
1962 * Iterate over all registered demuxers.
1964 * @param opaque a pointer where libavformat will store the iteration state. Must
1965 * point to NULL to start the iteration.
1967 * @return the next registered demuxer or NULL when the iteration is
1970 const AVInputFormat *av_demuxer_iterate(void **opaque);
1973 * Allocate an AVFormatContext.
1974 * avformat_free_context() can be used to free the context and everything
1975 * allocated by the framework within it.
1977 AVFormatContext *avformat_alloc_context(void);
1980 * Free an AVFormatContext and all its streams.
1981 * @param s context to free
1983 void avformat_free_context(AVFormatContext *s);
1986 * Get the AVClass for AVFormatContext. It can be used in combination with
1987 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
1989 * @see av_opt_find().
1991 const AVClass *avformat_get_class(void);
1994 * Add a new stream to a media file.
1996 * When demuxing, it is called by the demuxer in read_header(). If the
1997 * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
1998 * be called in read_packet().
2000 * When muxing, should be called by the user before avformat_write_header().
2002 * User is required to call avcodec_close() and avformat_free_context() to
2003 * clean up the allocation by avformat_new_stream().
2005 * @param s media file handle
2006 * @param c If non-NULL, the AVCodecContext corresponding to the new stream
2007 * will be initialized to use this codec. This is needed for e.g. codec-specific
2008 * defaults to be set, so codec should be provided if it is known.
2010 * @return newly created stream or NULL on error.
2012 AVStream *avformat_new_stream(AVFormatContext *s, const AVCodec *c);
2015 * Wrap an existing array as stream side data.
2018 * @param type side information type
2019 * @param data the side data array. It must be allocated with the av_malloc()
2020 * family of functions. The ownership of the data is transferred to
2022 * @param size side information size
2023 * @return zero on success, a negative AVERROR code on failure. On failure,
2024 * the stream is unchanged and the data remains owned by the caller.
2026 int av_stream_add_side_data(AVStream *st, enum AVPacketSideDataType type,
2027 uint8_t *data, size_t size);
2030 * Allocate new information from stream.
2032 * @param stream stream
2033 * @param type desired side information type
2034 * @param size side information size
2035 * @return pointer to fresh allocated data or NULL otherwise
2037 uint8_t *av_stream_new_side_data(AVStream *stream,
2038 #if FF_API_BUFFER_SIZE_T
2039 enum AVPacketSideDataType type, int size);
2041 enum AVPacketSideDataType type, size_t size);
2044 * Get side information from stream.
2046 * @param stream stream
2047 * @param type desired side information type
2048 * @param size If supplied, *size will be set to the size of the side data
2049 * or to zero if the desired side data is not present.
2050 * @return pointer to data if present or NULL otherwise
2052 uint8_t *av_stream_get_side_data(const AVStream *stream,
2053 #if FF_API_BUFFER_SIZE_T
2054 enum AVPacketSideDataType type, int *size);
2056 enum AVPacketSideDataType type, size_t *size);
2059 AVProgram *av_new_program(AVFormatContext *s, int id);
2067 * Allocate an AVFormatContext for an output format.
2068 * avformat_free_context() can be used to free the context and
2069 * everything allocated by the framework within it.
2071 * @param *ctx is set to the created format context, or to NULL in
2073 * @param oformat format to use for allocating the context, if NULL
2074 * format_name and filename are used instead
2075 * @param format_name the name of output format to use for allocating the
2076 * context, if NULL filename is used instead
2077 * @param filename the name of the filename to use for allocating the
2078 * context, may be NULL
2079 * @return >= 0 in case of success, a negative AVERROR code in case of
2082 int avformat_alloc_output_context2(AVFormatContext **ctx, const AVOutputFormat *oformat,
2083 const char *format_name, const char *filename);
2086 * @addtogroup lavf_decoding
2091 * Find AVInputFormat based on the short name of the input format.
2093 const AVInputFormat *av_find_input_format(const char *short_name);
2096 * Guess the file format.
2098 * @param pd data to be probed
2099 * @param is_opened Whether the file is already opened; determines whether
2100 * demuxers with or without AVFMT_NOFILE are probed.
2102 const AVInputFormat *av_probe_input_format(const AVProbeData *pd, int is_opened);
2105 * Guess the file format.
2107 * @param pd data to be probed
2108 * @param is_opened Whether the file is already opened; determines whether
2109 * demuxers with or without AVFMT_NOFILE are probed.
2110 * @param score_max A probe score larger that this is required to accept a
2111 * detection, the variable is set to the actual detection
2113 * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
2114 * to retry with a larger probe buffer.
2116 const AVInputFormat *av_probe_input_format2(const AVProbeData *pd,
2117 int is_opened, int *score_max);
2120 * Guess the file format.
2122 * @param is_opened Whether the file is already opened; determines whether
2123 * demuxers with or without AVFMT_NOFILE are probed.
2124 * @param score_ret The score of the best detection.
2126 const AVInputFormat *av_probe_input_format3(const AVProbeData *pd,
2127 int is_opened, int *score_ret);
2130 * Probe a bytestream to determine the input format. Each time a probe returns
2131 * with a score that is too low, the probe buffer size is increased and another
2132 * attempt is made. When the maximum probe size is reached, the input format
2133 * with the highest score is returned.
2135 * @param pb the bytestream to probe
2136 * @param fmt the input format is put here
2137 * @param url the url of the stream
2138 * @param logctx the log context
2139 * @param offset the offset within the bytestream to probe from
2140 * @param max_probe_size the maximum probe buffer size (zero for default)
2141 * @return the score in case of success, a negative value corresponding to an
2142 * the maximal score is AVPROBE_SCORE_MAX
2143 * AVERROR code otherwise
2145 int av_probe_input_buffer2(AVIOContext *pb, const AVInputFormat **fmt,
2146 const char *url, void *logctx,
2147 unsigned int offset, unsigned int max_probe_size);
2150 * Like av_probe_input_buffer2() but returns 0 on success
2152 int av_probe_input_buffer(AVIOContext *pb, const AVInputFormat **fmt,
2153 const char *url, void *logctx,
2154 unsigned int offset, unsigned int max_probe_size);
2157 * Open an input stream and read the header. The codecs are not opened.
2158 * The stream must be closed with avformat_close_input().
2160 * @param ps Pointer to user-supplied AVFormatContext (allocated by avformat_alloc_context).
2161 * May be a pointer to NULL, in which case an AVFormatContext is allocated by this
2162 * function and written into ps.
2163 * Note that a user-supplied AVFormatContext will be freed on failure.
2164 * @param url URL of the stream to open.
2165 * @param fmt If non-NULL, this parameter forces a specific input format.
2166 * Otherwise the format is autodetected.
2167 * @param options A dictionary filled with AVFormatContext and demuxer-private options.
2168 * On return this parameter will be destroyed and replaced with a dict containing
2169 * options that were not found. May be NULL.
2171 * @return 0 on success, a negative AVERROR on failure.
2173 * @note If you want to use custom IO, preallocate the format context and set its pb field.
2175 int avformat_open_input(AVFormatContext **ps, const char *url,
2176 const AVInputFormat *fmt, AVDictionary **options);
2178 #if FF_API_DEMUXER_OPEN
2180 * @deprecated Use an AVDictionary to pass options to a demuxer.
2182 attribute_deprecated
2183 int av_demuxer_open(AVFormatContext *ic);
2187 * Read packets of a media file to get stream information. This
2188 * is useful for file formats with no headers such as MPEG. This
2189 * function also computes the real framerate in case of MPEG-2 repeat
2191 * The logical file position is not changed by this function;
2192 * examined packets may be buffered for later processing.
2194 * @param ic media file handle
2195 * @param options If non-NULL, an ic.nb_streams long array of pointers to
2196 * dictionaries, where i-th member contains options for
2197 * codec corresponding to i-th stream.
2198 * On return each dictionary will be filled with options that were not found.
2199 * @return >=0 if OK, AVERROR_xxx on error
2201 * @note this function isn't guaranteed to open all the codecs, so
2202 * options being non-empty at return is a perfectly normal behavior.
2204 * @todo Let the user decide somehow what information is needed so that
2205 * we do not waste time getting stuff the user does not need.
2207 int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options);
2210 * Find the programs which belong to a given stream.
2212 * @param ic media file handle
2213 * @param last the last found program, the search will start after this
2214 * program, or from the beginning if it is NULL
2215 * @param s stream index
2216 * @return the next program which belongs to s, NULL if no program is found or
2217 * the last program is not among the programs of ic.
2219 AVProgram *av_find_program_from_stream(AVFormatContext *ic, AVProgram *last, int s);
2221 void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx);
2224 * Find the "best" stream in the file.
2225 * The best stream is determined according to various heuristics as the most
2226 * likely to be what the user expects.
2227 * If the decoder parameter is non-NULL, av_find_best_stream will find the
2228 * default decoder for the stream's codec; streams for which no decoder can
2229 * be found are ignored.
2231 * @param ic media file handle
2232 * @param type stream type: video, audio, subtitles, etc.
2233 * @param wanted_stream_nb user-requested stream number,
2234 * or -1 for automatic selection
2235 * @param related_stream try to find a stream related (eg. in the same
2236 * program) to this one, or -1 if none
2237 * @param decoder_ret if non-NULL, returns the decoder for the
2239 * @param flags flags; none are currently defined
2240 * @return the non-negative stream number in case of success,
2241 * AVERROR_STREAM_NOT_FOUND if no stream with the requested type
2243 * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
2244 * @note If av_find_best_stream returns successfully and decoder_ret is not
2245 * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
2247 int av_find_best_stream(AVFormatContext *ic,
2248 enum AVMediaType type,
2249 int wanted_stream_nb,
2251 AVCodec **decoder_ret,
2255 * Return the next frame of a stream.
2256 * This function returns what is stored in the file, and does not validate
2257 * that what is there are valid frames for the decoder. It will split what is
2258 * stored in the file into frames and return one for each call. It will not
2259 * omit invalid data between valid frames so as to give the decoder the maximum
2260 * information possible for decoding.
2262 * On success, the returned packet is reference-counted (pkt->buf is set) and
2263 * valid indefinitely. The packet must be freed with av_packet_unref() when
2264 * it is no longer needed. For video, the packet contains exactly one frame.
2265 * For audio, it contains an integer number of frames if each frame has
2266 * a known fixed size (e.g. PCM or ADPCM data). If the audio frames have
2267 * a variable size (e.g. MPEG audio), then it contains one frame.
2269 * pkt->pts, pkt->dts and pkt->duration are always set to correct
2270 * values in AVStream.time_base units (and guessed if the format cannot
2271 * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
2272 * has B-frames, so it is better to rely on pkt->dts if you do not
2273 * decompress the payload.
2275 * @return 0 if OK, < 0 on error or end of file. On error, pkt will be blank
2276 * (as if it came from av_packet_alloc()).
2278 * @note pkt will be initialized, so it may be uninitialized, but it must not
2279 * contain data that needs to be freed.
2281 int av_read_frame(AVFormatContext *s, AVPacket *pkt);
2284 * Seek to the keyframe at timestamp.
2285 * 'timestamp' in 'stream_index'.
2287 * @param s media file handle
2288 * @param stream_index If stream_index is (-1), a default
2289 * stream is selected, and timestamp is automatically converted
2290 * from AV_TIME_BASE units to the stream specific time_base.
2291 * @param timestamp Timestamp in AVStream.time_base units
2292 * or, if no stream is specified, in AV_TIME_BASE units.
2293 * @param flags flags which select direction and seeking mode
2294 * @return >= 0 on success
2296 int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
2300 * Seek to timestamp ts.
2301 * Seeking will be done so that the point from which all active streams
2302 * can be presented successfully will be closest to ts and within min/max_ts.
2303 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
2305 * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
2306 * are the file position (this may not be supported by all demuxers).
2307 * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
2308 * in the stream with stream_index (this may not be supported by all demuxers).
2309 * Otherwise all timestamps are in units of the stream selected by stream_index
2310 * or if stream_index is -1, in AV_TIME_BASE units.
2311 * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
2312 * keyframes (this may not be supported by all demuxers).
2313 * If flags contain AVSEEK_FLAG_BACKWARD, it is ignored.
2315 * @param s media file handle
2316 * @param stream_index index of the stream which is used as time base reference
2317 * @param min_ts smallest acceptable timestamp
2318 * @param ts target timestamp
2319 * @param max_ts largest acceptable timestamp
2320 * @param flags flags
2321 * @return >=0 on success, error code otherwise
2323 * @note This is part of the new seek API which is still under construction.
2325 int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
2328 * Discard all internally buffered data. This can be useful when dealing with
2329 * discontinuities in the byte stream. Generally works only with formats that
2330 * can resync. This includes headerless formats like MPEG-TS/TS but should also
2331 * work with NUT, Ogg and in a limited way AVI for example.
2333 * The set of streams, the detected duration, stream parameters and codecs do
2334 * not change when calling this function. If you want a complete reset, it's
2335 * better to open a new AVFormatContext.
2337 * This does not flush the AVIOContext (s->pb). If necessary, call
2338 * avio_flush(s->pb) before calling this function.
2340 * @param s media file handle
2341 * @return >=0 on success, error code otherwise
2343 int avformat_flush(AVFormatContext *s);
2346 * Start playing a network-based stream (e.g. RTSP stream) at the
2349 int av_read_play(AVFormatContext *s);
2352 * Pause a network-based stream (e.g. RTSP stream).
2354 * Use av_read_play() to resume it.
2356 int av_read_pause(AVFormatContext *s);
2359 * Close an opened input AVFormatContext. Free it and all its contents
2360 * and set *s to NULL.
2362 void avformat_close_input(AVFormatContext **s);
2367 #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
2368 #define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
2369 #define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
2370 #define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
2373 * @addtogroup lavf_encoding
2377 #define AVSTREAM_INIT_IN_WRITE_HEADER 0 ///< stream parameters initialized in avformat_write_header
2378 #define AVSTREAM_INIT_IN_INIT_OUTPUT 1 ///< stream parameters initialized in avformat_init_output
2381 * Allocate the stream private data and write the stream header to
2382 * an output media file.
2384 * @param s Media file handle, must be allocated with avformat_alloc_context().
2385 * Its oformat field must be set to the desired output format;
2386 * Its pb field must be set to an already opened AVIOContext.
2387 * @param options An AVDictionary filled with AVFormatContext and muxer-private options.
2388 * On return this parameter will be destroyed and replaced with a dict containing
2389 * options that were not found. May be NULL.
2391 * @return AVSTREAM_INIT_IN_WRITE_HEADER on success if the codec had not already been fully initialized in avformat_init,
2392 * AVSTREAM_INIT_IN_INIT_OUTPUT on success if the codec had already been fully initialized in avformat_init,
2393 * negative AVERROR on failure.
2395 * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_init_output.
2397 av_warn_unused_result
2398 int avformat_write_header(AVFormatContext *s, AVDictionary **options);
2401 * Allocate the stream private data and initialize the codec, but do not write the header.
2402 * May optionally be used before avformat_write_header to initialize stream parameters
2403 * before actually writing the header.
2404 * If using this function, do not pass the same options to avformat_write_header.
2406 * @param s Media file handle, must be allocated with avformat_alloc_context().
2407 * Its oformat field must be set to the desired output format;
2408 * Its pb field must be set to an already opened AVIOContext.
2409 * @param options An AVDictionary filled with AVFormatContext and muxer-private options.
2410 * On return this parameter will be destroyed and replaced with a dict containing
2411 * options that were not found. May be NULL.
2413 * @return AVSTREAM_INIT_IN_WRITE_HEADER on success if the codec requires avformat_write_header to fully initialize,
2414 * AVSTREAM_INIT_IN_INIT_OUTPUT on success if the codec has been fully initialized,
2415 * negative AVERROR on failure.
2417 * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_write_header.
2419 av_warn_unused_result
2420 int avformat_init_output(AVFormatContext *s, AVDictionary **options);
2423 * Write a packet to an output media file.
2425 * This function passes the packet directly to the muxer, without any buffering
2426 * or reordering. The caller is responsible for correctly interleaving the
2427 * packets if the format requires it. Callers that want libavformat to handle
2428 * the interleaving should call av_interleaved_write_frame() instead of this
2431 * @param s media file handle
2432 * @param pkt The packet containing the data to be written. Note that unlike
2433 * av_interleaved_write_frame(), this function does not take
2434 * ownership of the packet passed to it (though some muxers may make
2435 * an internal reference to the input packet).
2437 * This parameter can be NULL (at any time, not just at the end), in
2438 * order to immediately flush data buffered within the muxer, for
2439 * muxers that buffer up data internally before writing it to the
2442 * Packet's @ref AVPacket.stream_index "stream_index" field must be
2443 * set to the index of the corresponding stream in @ref
2444 * AVFormatContext.streams "s->streams".
2446 * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2447 * must be set to correct values in the stream's timebase (unless the
2448 * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2449 * they can be set to AV_NOPTS_VALUE).
2450 * The dts for subsequent packets passed to this function must be strictly
2451 * increasing when compared in their respective timebases (unless the
2452 * output format is flagged with the AVFMT_TS_NONSTRICT, then they
2453 * merely have to be nondecreasing). @ref AVPacket.duration
2454 * "duration") should also be set if known.
2455 * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush
2457 * @see av_interleaved_write_frame()
2459 int av_write_frame(AVFormatContext *s, AVPacket *pkt);
2462 * Write a packet to an output media file ensuring correct interleaving.
2464 * This function will buffer the packets internally as needed to make sure the
2465 * packets in the output file are properly interleaved in the order of
2466 * increasing dts. Callers doing their own interleaving should call
2467 * av_write_frame() instead of this function.
2469 * Using this function instead of av_write_frame() can give muxers advance
2470 * knowledge of future packets, improving e.g. the behaviour of the mp4
2471 * muxer for VFR content in fragmenting mode.
2473 * @param s media file handle
2474 * @param pkt The packet containing the data to be written.
2476 * If the packet is reference-counted, this function will take
2477 * ownership of this reference and unreference it later when it sees
2479 * The caller must not access the data through this reference after
2480 * this function returns. If the packet is not reference-counted,
2481 * libavformat will make a copy.
2483 * This parameter can be NULL (at any time, not just at the end), to
2484 * flush the interleaving queues.
2486 * Packet's @ref AVPacket.stream_index "stream_index" field must be
2487 * set to the index of the corresponding stream in @ref
2488 * AVFormatContext.streams "s->streams".
2490 * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2491 * must be set to correct values in the stream's timebase (unless the
2492 * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2493 * they can be set to AV_NOPTS_VALUE).
2494 * The dts for subsequent packets in one stream must be strictly
2495 * increasing (unless the output format is flagged with the
2496 * AVFMT_TS_NONSTRICT, then they merely have to be nondecreasing).
2497 * @ref AVPacket.duration "duration") should also be set if known.
2499 * @return 0 on success, a negative AVERROR on error. Libavformat will always
2500 * take care of freeing the packet, even if this function fails.
2502 * @see av_write_frame(), AVFormatContext.max_interleave_delta
2504 int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
2507 * Write an uncoded frame to an output media file.
2509 * The frame must be correctly interleaved according to the container
2510 * specification; if not, av_interleaved_write_uncoded_frame() must be used.
2512 * See av_interleaved_write_uncoded_frame() for details.
2514 int av_write_uncoded_frame(AVFormatContext *s, int stream_index,
2518 * Write an uncoded frame to an output media file.
2520 * If the muxer supports it, this function makes it possible to write an AVFrame
2521 * structure directly, without encoding it into a packet.
2522 * It is mostly useful for devices and similar special muxers that use raw
2523 * video or PCM data and will not serialize it into a byte stream.
2525 * To test whether it is possible to use it with a given muxer and stream,
2526 * use av_write_uncoded_frame_query().
2528 * The caller gives up ownership of the frame and must not access it
2531 * @return >=0 for success, a negative code on error
2533 int av_interleaved_write_uncoded_frame(AVFormatContext *s, int stream_index,
2537 * Test whether a muxer supports uncoded frame.
2539 * @return >=0 if an uncoded frame can be written to that muxer and stream,
2542 int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index);
2545 * Write the stream trailer to an output media file and free the
2546 * file private data.
2548 * May only be called after a successful call to avformat_write_header.
2550 * @param s media file handle
2551 * @return 0 if OK, AVERROR_xxx on error
2553 int av_write_trailer(AVFormatContext *s);
2556 * Return the output format in the list of registered output formats
2557 * which best matches the provided parameters, or return NULL if
2558 * there is no match.
2560 * @param short_name if non-NULL checks if short_name matches with the
2561 * names of the registered formats
2562 * @param filename if non-NULL checks if filename terminates with the
2563 * extensions of the registered formats
2564 * @param mime_type if non-NULL checks if mime_type matches with the
2565 * MIME type of the registered formats
2567 const AVOutputFormat *av_guess_format(const char *short_name,
2568 const char *filename,
2569 const char *mime_type);
2572 * Guess the codec ID based upon muxer and filename.
2574 enum AVCodecID av_guess_codec(const AVOutputFormat *fmt, const char *short_name,
2575 const char *filename, const char *mime_type,
2576 enum AVMediaType type);
2579 * Get timing information for the data currently output.
2580 * The exact meaning of "currently output" depends on the format.
2581 * It is mostly relevant for devices that have an internal buffer and/or
2582 * work in real time.
2583 * @param s media file handle
2584 * @param stream stream in the media file
2585 * @param[out] dts DTS of the last packet output for the stream, in stream
2587 * @param[out] wall absolute time when that packet whas output,
2589 * @return 0 if OK, AVERROR(ENOSYS) if the format does not support it
2590 * Note: some formats or devices may not allow to measure dts and wall
2593 int av_get_output_timestamp(struct AVFormatContext *s, int stream,
2594 int64_t *dts, int64_t *wall);
2603 * @defgroup lavf_misc Utility functions
2607 * Miscellaneous utility functions related to both muxing and demuxing
2612 * Send a nice hexadecimal dump of a buffer to the specified file stream.
2614 * @param f The file stream pointer where the dump should be sent to.
2616 * @param size buffer size
2618 * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2
2620 void av_hex_dump(FILE *f, const uint8_t *buf, int size);
2623 * Send a nice hexadecimal dump of a buffer to the log.
2625 * @param avcl A pointer to an arbitrary struct of which the first field is a
2626 * pointer to an AVClass struct.
2627 * @param level The importance level of the message, lower values signifying
2628 * higher importance.
2630 * @param size buffer size
2632 * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2
2634 void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size);
2637 * Send a nice dump of a packet to the specified file stream.
2639 * @param f The file stream pointer where the dump should be sent to.
2640 * @param pkt packet to dump
2641 * @param dump_payload True if the payload must be displayed, too.
2642 * @param st AVStream that the packet belongs to
2644 void av_pkt_dump2(FILE *f, const AVPacket *pkt, int dump_payload, const AVStream *st);
2648 * Send a nice dump of a packet to the log.
2650 * @param avcl A pointer to an arbitrary struct of which the first field is a
2651 * pointer to an AVClass struct.
2652 * @param level The importance level of the message, lower values signifying
2653 * higher importance.
2654 * @param pkt packet to dump
2655 * @param dump_payload True if the payload must be displayed, too.
2656 * @param st AVStream that the packet belongs to
2658 void av_pkt_dump_log2(void *avcl, int level, const AVPacket *pkt, int dump_payload,
2659 const AVStream *st);
2662 * Get the AVCodecID for the given codec tag tag.
2663 * If no codec id is found returns AV_CODEC_ID_NONE.
2665 * @param tags list of supported codec_id-codec_tag pairs, as stored
2666 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2667 * @param tag codec tag to match to a codec ID
2669 enum AVCodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
2672 * Get the codec tag for the given codec id id.
2673 * If no codec tag is found returns 0.
2675 * @param tags list of supported codec_id-codec_tag pairs, as stored
2676 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2677 * @param id codec ID to match to a codec tag
2679 unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id);
2682 * Get the codec tag for the given codec id.
2684 * @param tags list of supported codec_id - codec_tag pairs, as stored
2685 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2686 * @param id codec id that should be searched for in the list
2687 * @param tag A pointer to the found tag
2688 * @return 0 if id was not found in tags, > 0 if it was found
2690 int av_codec_get_tag2(const struct AVCodecTag * const *tags, enum AVCodecID id,
2693 int av_find_default_stream_index(AVFormatContext *s);
2696 * Get the index for a specific timestamp.
2698 * @param st stream that the timestamp belongs to
2699 * @param timestamp timestamp to retrieve the index for
2700 * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
2701 * to the timestamp which is <= the requested one, if backward
2702 * is 0, then it will be >=
2703 * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
2704 * @return < 0 if no such timestamp could be found
2706 int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
2709 * Get the index entry count for the given AVStream.
2712 * @return the number of index entries in the stream
2714 int avformat_index_get_entries_count(const AVStream *st);
2717 * Get the AVIndexEntry corresponding to the given index.
2719 * @param st Stream containing the requested AVIndexEntry.
2720 * @param idx The desired index.
2721 * @return A pointer to the requested AVIndexEntry if it exists, NULL otherwise.
2723 * @note The pointer returned by this function is only guaranteed to be valid
2724 * until any function that could alter the stream or the AVFormatContext
2725 * that contains it is called.
2727 const AVIndexEntry *avformat_index_get_entry(const AVStream *st, int idx);
2730 * Get the AVIndexEntry corresponding to the given timestamp.
2732 * @param st Stream containing the requested AVIndexEntry.
2733 * @param timestamp Timestamp to retrieve the index entry for.
2734 * @param flags If AVSEEK_FLAG_BACKWARD then the returned entry will correspond
2735 * to the timestamp which is <= the requested one, if backward
2736 * is 0, then it will be >=
2737 * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise.
2738 * @return A pointer to the requested AVIndexEntry if it exists, NULL otherwise.
2740 * @note The pointer returned by this function is only guaranteed to be valid
2741 * until any function that could alter the stream or the AVFormatContext
2742 * that contains it is called.
2744 const AVIndexEntry *avformat_index_get_entry_from_timestamp(const AVStream *st,
2745 int64_t wanted_timestamp,
2748 * Add an index entry into a sorted list. Update the entry if the list
2749 * already contains it.
2751 * @param timestamp timestamp in the time base of the given stream
2753 int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
2754 int size, int distance, int flags);
2758 * Split a URL string into components.
2760 * The pointers to buffers for storing individual components may be null,
2761 * in order to ignore that component. Buffers for components not found are
2762 * set to empty strings. If the port is not found, it is set to a negative
2765 * @param proto the buffer for the protocol
2766 * @param proto_size the size of the proto buffer
2767 * @param authorization the buffer for the authorization
2768 * @param authorization_size the size of the authorization buffer
2769 * @param hostname the buffer for the host name
2770 * @param hostname_size the size of the hostname buffer
2771 * @param port_ptr a pointer to store the port number in
2772 * @param path the buffer for the path
2773 * @param path_size the size of the path buffer
2774 * @param url the URL to split
2776 void av_url_split(char *proto, int proto_size,
2777 char *authorization, int authorization_size,
2778 char *hostname, int hostname_size,
2780 char *path, int path_size,
2785 * Print detailed information about the input or output format, such as
2786 * duration, bitrate, streams, container, programs, metadata, side data,
2787 * codec and time base.
2789 * @param ic the context to analyze
2790 * @param index index of the stream to dump information about
2791 * @param url the URL to print, such as source or destination file
2792 * @param is_output Select whether the specified context is an input(0) or output(1)
2794 void av_dump_format(AVFormatContext *ic,
2800 #define AV_FRAME_FILENAME_FLAGS_MULTIPLE 1 ///< Allow multiple %d
2803 * Return in 'buf' the path with '%d' replaced by a number.
2805 * Also handles the '%0nd' format where 'n' is the total number
2806 * of digits and '%%'.
2808 * @param buf destination buffer
2809 * @param buf_size destination buffer size
2810 * @param path numbered sequence string
2811 * @param number frame number
2812 * @param flags AV_FRAME_FILENAME_FLAGS_*
2813 * @return 0 if OK, -1 on format error
2815 int av_get_frame_filename2(char *buf, int buf_size,
2816 const char *path, int number, int flags);
2818 int av_get_frame_filename(char *buf, int buf_size,
2819 const char *path, int number);
2822 * Check whether filename actually is a numbered sequence generator.
2824 * @param filename possible numbered sequence string
2825 * @return 1 if a valid numbered sequence string, 0 otherwise
2827 int av_filename_number_test(const char *filename);
2830 * Generate an SDP for an RTP session.
2832 * Note, this overwrites the id values of AVStreams in the muxer contexts
2833 * for getting unique dynamic payload types.
2835 * @param ac array of AVFormatContexts describing the RTP streams. If the
2836 * array is composed by only one context, such context can contain
2837 * multiple AVStreams (one AVStream per RTP stream). Otherwise,
2838 * all the contexts in the array (an AVCodecContext per RTP stream)
2839 * must contain only one AVStream.
2840 * @param n_files number of AVCodecContexts contained in ac
2841 * @param buf buffer where the SDP will be stored (must be allocated by
2843 * @param size the size of the buffer
2844 * @return 0 if OK, AVERROR_xxx on error
2846 int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size);
2849 * Return a positive value if the given filename has one of the given
2850 * extensions, 0 otherwise.
2852 * @param filename file name to check against the given extensions
2853 * @param extensions a comma-separated list of filename extensions
2855 int av_match_ext(const char *filename, const char *extensions);
2858 * Test if the given container can store a codec.
2860 * @param ofmt container to check for compatibility
2861 * @param codec_id codec to potentially store in container
2862 * @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
2864 * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
2865 * A negative number if this information is not available.
2867 int avformat_query_codec(const AVOutputFormat *ofmt, enum AVCodecID codec_id,
2868 int std_compliance);
2871 * @defgroup riff_fourcc RIFF FourCCs
2873 * Get the tables mapping RIFF FourCCs to libavcodec AVCodecIDs. The tables are
2874 * meant to be passed to av_codec_get_id()/av_codec_get_tag() as in the
2877 * uint32_t tag = MKTAG('H', '2', '6', '4');
2878 * const struct AVCodecTag *table[] = { avformat_get_riff_video_tags(), 0 };
2879 * enum AVCodecID id = av_codec_get_id(table, tag);
2883 * @return the table mapping RIFF FourCCs for video to libavcodec AVCodecID.
2885 const struct AVCodecTag *avformat_get_riff_video_tags(void);
2887 * @return the table mapping RIFF FourCCs for audio to AVCodecID.
2889 const struct AVCodecTag *avformat_get_riff_audio_tags(void);
2891 * @return the table mapping MOV FourCCs for video to libavcodec AVCodecID.
2893 const struct AVCodecTag *avformat_get_mov_video_tags(void);
2895 * @return the table mapping MOV FourCCs for audio to AVCodecID.
2897 const struct AVCodecTag *avformat_get_mov_audio_tags(void);
2904 * Guess the sample aspect ratio of a frame, based on both the stream and the
2905 * frame aspect ratio.
2907 * Since the frame aspect ratio is set by the codec but the stream aspect ratio
2908 * is set by the demuxer, these two may not be equal. This function tries to
2909 * return the value that you should use if you would like to display the frame.
2911 * Basic logic is to use the stream aspect ratio if it is set to something sane
2912 * otherwise use the frame aspect ratio. This way a container setting, which is
2913 * usually easy to modify can override the coded value in the frames.
2915 * @param format the format context which the stream is part of
2916 * @param stream the stream which the frame is part of
2917 * @param frame the frame with the aspect ratio to be determined
2918 * @return the guessed (valid) sample_aspect_ratio, 0/1 if no idea
2920 AVRational av_guess_sample_aspect_ratio(AVFormatContext *format, AVStream *stream, AVFrame *frame);
2923 * Guess the frame rate, based on both the container and codec information.
2925 * @param ctx the format context which the stream is part of
2926 * @param stream the stream which the frame is part of
2927 * @param frame the frame for which the frame rate should be determined, may be NULL
2928 * @return the guessed (valid) frame rate, 0/1 if no idea
2930 AVRational av_guess_frame_rate(AVFormatContext *ctx, AVStream *stream, AVFrame *frame);
2933 * Check if the stream st contained in s is matched by the stream specifier
2936 * See the "stream specifiers" chapter in the documentation for the syntax
2939 * @return >0 if st is matched by spec;
2940 * 0 if st is not matched by spec;
2941 * AVERROR code if spec is invalid
2943 * @note A stream specifier can match several streams in the format.
2945 int avformat_match_stream_specifier(AVFormatContext *s, AVStream *st,
2948 int avformat_queue_attached_pictures(AVFormatContext *s);
2950 enum AVTimebaseSource {
2951 AVFMT_TBCF_AUTO = -1,
2954 #if FF_API_R_FRAME_RATE
2955 AVFMT_TBCF_R_FRAMERATE,
2960 * Transfer internal timing information from one stream to another.
2962 * This function is useful when doing stream copy.
2964 * @param ofmt target output format for ost
2965 * @param ost output stream which needs timings copy and adjustments
2966 * @param ist reference input stream to copy timings from
2967 * @param copy_tb define from where the stream codec timebase needs to be imported
2969 int avformat_transfer_internal_stream_timing_info(const AVOutputFormat *ofmt,
2970 AVStream *ost, const AVStream *ist,
2971 enum AVTimebaseSource copy_tb);
2974 * Get the internal codec timebase from a stream.
2976 * @param st input stream to extract the timebase from
2978 AVRational av_stream_get_codec_timebase(const AVStream *st);
2984 #endif /* AVFORMAT_AVFORMAT_H */