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). Before using lavf, you need to call
40 * av_register_all() to register all compiled muxers, demuxers and protocols.
41 * Unless you are absolutely sure you won't use libavformat's network
42 * capabilities, you should also call avformat_network_init().
44 * A supported input format is described by an AVInputFormat struct, conversely
45 * an output format is described by AVOutputFormat. You can iterate over all
46 * registered input/output formats using the av_iformat_next() /
47 * av_oformat_next() functions. The protocols layer is not part of the public
48 * API, so you can only get the names of supported protocols with the
49 * avio_enum_protocols() function.
51 * Main lavf structure used for both muxing and demuxing is AVFormatContext,
52 * which exports all information about the file being read or written. As with
53 * most Libavformat structures, its size is not part of public ABI, so it cannot be
54 * allocated on stack or directly with av_malloc(). To create an
55 * AVFormatContext, use avformat_alloc_context() (some functions, like
56 * avformat_open_input() might do that for you).
58 * Most importantly an AVFormatContext contains:
59 * @li the @ref AVFormatContext.iformat "input" or @ref AVFormatContext.oformat
60 * "output" format. It is either autodetected or set by user for input;
61 * always set by user for output.
62 * @li an @ref AVFormatContext.streams "array" of AVStreams, which describe all
63 * elementary streams stored in the file. AVStreams are typically referred to
64 * using their index in this array.
65 * @li an @ref AVFormatContext.pb "I/O context". It is either opened by lavf or
66 * set by user for input, always set by user for output (unless you are dealing
67 * with an AVFMT_NOFILE format).
69 * @section lavf_options Passing options to (de)muxers
70 * It is possible to configure lavf muxers and demuxers using the @ref avoptions
71 * mechanism. Generic (format-independent) libavformat options are provided by
72 * AVFormatContext, they can be examined from a user program by calling
73 * av_opt_next() / av_opt_find() on an allocated AVFormatContext (or its AVClass
74 * from avformat_get_class()). Private (format-specific) options are provided by
75 * AVFormatContext.priv_data if and only if AVInputFormat.priv_class /
76 * AVOutputFormat.priv_class of the corresponding format struct is non-NULL.
77 * Further options may be provided by the @ref AVFormatContext.pb "I/O context",
78 * if its AVClass is non-NULL, and the protocols layer. See the discussion on
79 * nesting in @ref avoptions documentation to learn how to access those.
82 * URL strings in libavformat are made of a scheme/protocol, a ':', and a
83 * scheme specific string. URLs without a scheme and ':' used for local files
84 * are supported but deprecated. "file:" should be used for local files.
86 * It is important that the scheme string is not taken from untrusted
87 * sources without checks.
89 * Note that some schemes/protocols are quite powerful, allowing access to
90 * both local and remote files, parts of them, concatenations of them, local
91 * audio and video devices and so on.
95 * @defgroup lavf_decoding Demuxing
97 * Demuxers read a media file and split it into chunks of data (@em packets). A
98 * @ref AVPacket "packet" contains one or more encoded frames which belongs to a
99 * single elementary stream. In the lavf API this process is represented by the
100 * avformat_open_input() function for opening a file, av_read_frame() for
101 * reading a single packet and finally avformat_close_input(), which does the
104 * @section lavf_decoding_open Opening a media file
105 * The minimum information required to open a file is its URL, which
106 * is passed to avformat_open_input(), as in the following code:
108 * const char *url = "file:in.mp3";
109 * AVFormatContext *s = NULL;
110 * int ret = avformat_open_input(&s, url, NULL, NULL);
114 * The above code attempts to allocate an AVFormatContext, open the
115 * specified file (autodetecting the format) and read the header, exporting the
116 * information stored there into s. Some formats do not have a header or do not
117 * store enough information there, so it is recommended that you call the
118 * avformat_find_stream_info() function which tries to read and decode a few
119 * frames to find missing information.
121 * In some cases you might want to preallocate an AVFormatContext yourself with
122 * avformat_alloc_context() and do some tweaking on it before passing it to
123 * avformat_open_input(). One such case is when you want to use custom functions
124 * for reading input data instead of lavf internal I/O layer.
125 * To do that, create your own AVIOContext with avio_alloc_context(), passing
126 * your reading callbacks to it. Then set the @em pb field of your
127 * AVFormatContext to newly created AVIOContext.
129 * Since the format of the opened file is in general not known until after
130 * avformat_open_input() has returned, it is not possible to set demuxer private
131 * options on a preallocated context. Instead, the options should be passed to
132 * avformat_open_input() wrapped in an AVDictionary:
134 * AVDictionary *options = NULL;
135 * av_dict_set(&options, "video_size", "640x480", 0);
136 * av_dict_set(&options, "pixel_format", "rgb24", 0);
138 * if (avformat_open_input(&s, url, NULL, &options) < 0)
140 * av_dict_free(&options);
142 * This code passes the private options 'video_size' and 'pixel_format' to the
143 * demuxer. They would be necessary for e.g. the rawvideo demuxer, since it
144 * cannot know how to interpret raw video data otherwise. If the format turns
145 * out to be something different than raw video, those options will not be
146 * recognized by the demuxer and therefore will not be applied. Such unrecognized
147 * options are then returned in the options dictionary (recognized options are
148 * consumed). The calling program can handle such unrecognized options as it
151 * AVDictionaryEntry *e;
152 * if (e = av_dict_get(options, "", NULL, AV_DICT_IGNORE_SUFFIX)) {
153 * fprintf(stderr, "Option %s not recognized by the demuxer.\n", e->key);
158 * After you have finished reading the file, you must close it with
159 * avformat_close_input(). It will free everything associated with the file.
161 * @section lavf_decoding_read Reading from an opened file
162 * Reading data from an opened AVFormatContext is done by repeatedly calling
163 * av_read_frame() on it. Each call, if successful, will return an AVPacket
164 * containing encoded data for one AVStream, identified by
165 * AVPacket.stream_index. This packet may be passed straight into the libavcodec
166 * decoding functions avcodec_send_packet() or avcodec_decode_subtitle2() if the
167 * caller wishes to decode the data.
169 * AVPacket.pts, AVPacket.dts and AVPacket.duration timing information will be
170 * set if known. They may also be unset (i.e. AV_NOPTS_VALUE for
171 * pts/dts, 0 for duration) if the stream does not provide them. The timing
172 * information will be in AVStream.time_base units, i.e. it has to be
173 * multiplied by the timebase to convert them to seconds.
175 * If AVPacket.buf is set on the returned packet, then the packet is
176 * allocated dynamically and the user may keep it indefinitely.
177 * Otherwise, if AVPacket.buf is NULL, the packet data is backed by a
178 * static storage somewhere inside the demuxer and the packet is only valid
179 * until the next av_read_frame() call or closing the file. If the caller
180 * requires a longer lifetime, av_dup_packet() will make an av_malloc()ed copy
182 * In both cases, the packet must be freed with av_packet_unref() when it is no
185 * @section lavf_decoding_seek Seeking
188 * @defgroup lavf_encoding Muxing
190 * Muxers take encoded data in the form of @ref AVPacket "AVPackets" and write
191 * it into files or other output bytestreams in the specified container format.
193 * The main API functions for muxing are avformat_write_header() for writing the
194 * file header, av_write_frame() / av_interleaved_write_frame() for writing the
195 * packets and av_write_trailer() for finalizing the file.
197 * At the beginning of the muxing process, the caller must first call
198 * avformat_alloc_context() to create a muxing context. The caller then sets up
199 * the muxer by filling the various fields in this context:
201 * - The @ref AVFormatContext.oformat "oformat" field must be set to select the
202 * muxer that will be used.
203 * - Unless the format is of the AVFMT_NOFILE type, the @ref AVFormatContext.pb
204 * "pb" field must be set to an opened IO context, either returned from
205 * avio_open2() or a custom one.
206 * - Unless the format is of the AVFMT_NOSTREAMS type, at least one stream must
207 * be created with the avformat_new_stream() function. The caller should fill
208 * the @ref AVStream.codecpar "stream codec parameters" information, such as the
209 * codec @ref AVCodecParameters.codec_type "type", @ref AVCodecParameters.codec_id
210 * "id" and other parameters (e.g. width / height, the pixel or sample format,
211 * etc.) as known. The @ref AVStream.time_base "stream timebase" should
212 * be set to the timebase that the caller desires to use for this stream (note
213 * that the timebase actually used by the muxer can be different, as will be
215 * - It is advised to manually initialize only the relevant fields in
216 * AVCodecParameters, rather than using @ref avcodec_parameters_copy() during
217 * remuxing: there is no guarantee that the codec context values remain valid
218 * for both input and output format contexts.
219 * - The caller may fill in additional information, such as @ref
220 * AVFormatContext.metadata "global" or @ref AVStream.metadata "per-stream"
221 * metadata, @ref AVFormatContext.chapters "chapters", @ref
222 * AVFormatContext.programs "programs", etc. as described in the
223 * AVFormatContext documentation. Whether such information will actually be
224 * stored in the output depends on what the container format and the muxer
227 * When the muxing context is fully set up, the caller must call
228 * avformat_write_header() to initialize the muxer internals and write the file
229 * header. Whether anything actually is written to the IO context at this step
230 * depends on the muxer, but this function must always be called. Any muxer
231 * private options must be passed in the options parameter to this function.
233 * The data is then sent to the muxer by repeatedly calling av_write_frame() or
234 * av_interleaved_write_frame() (consult those functions' documentation for
235 * discussion on the difference between them; only one of them may be used with
236 * a single muxing context, they should not be mixed). Do note that the timing
237 * information on the packets sent to the muxer must be in the corresponding
238 * AVStream's timebase. That timebase is set by the muxer (in the
239 * avformat_write_header() step) and may be different from the timebase
240 * requested by the caller.
242 * Once all the data has been written, the caller must call av_write_trailer()
243 * to flush any buffered packets and finalize the output file, then close the IO
244 * context (if any) and finally free the muxing context with
245 * avformat_free_context().
248 * @defgroup lavf_io I/O Read/Write
250 * @section lavf_io_dirlist Directory listing
251 * The directory listing API makes it possible to list files on remote servers.
253 * Some of possible use cases:
254 * - an "open file" dialog to choose files from a remote location,
255 * - a recursive media finder providing a player with an ability to play all
256 * files from a given directory.
258 * @subsection lavf_io_dirlist_open Opening a directory
259 * At first, a directory needs to be opened by calling avio_open_dir()
260 * supplied with a URL and, optionally, ::AVDictionary containing
261 * protocol-specific parameters. The function returns zero or positive
262 * integer and allocates AVIODirContext on success.
265 * AVIODirContext *ctx = NULL;
266 * if (avio_open_dir(&ctx, "smb://example.com/some_dir", NULL) < 0) {
267 * fprintf(stderr, "Cannot open directory.\n");
272 * This code tries to open a sample directory using smb protocol without
273 * any additional parameters.
275 * @subsection lavf_io_dirlist_read Reading entries
276 * Each directory's entry (i.e. file, another directory, anything else
277 * within ::AVIODirEntryType) is represented by AVIODirEntry.
278 * Reading consecutive entries from an opened AVIODirContext is done by
279 * repeatedly calling avio_read_dir() on it. Each call returns zero or
280 * positive integer if successful. Reading can be stopped right after the
281 * NULL entry has been read -- it means there are no entries left to be
282 * read. The following code reads all entries from a directory associated
283 * with ctx and prints their names to standard output.
285 * AVIODirEntry *entry = NULL;
287 * if (avio_read_dir(ctx, &entry) < 0) {
288 * fprintf(stderr, "Cannot list directory.\n");
293 * printf("%s\n", entry->name);
294 * avio_free_directory_entry(&entry);
299 * @defgroup lavf_codec Demuxers
301 * @defgroup lavf_codec_native Native Demuxers
304 * @defgroup lavf_codec_wrappers External library wrappers
308 * @defgroup lavf_protos I/O Protocols
311 * @defgroup lavf_internal Internal
318 #include <stdio.h> /* FILE */
319 #include "libavcodec/avcodec.h"
320 #include "libavutil/dict.h"
321 #include "libavutil/log.h"
324 #include "libavformat/version.h"
326 struct AVFormatContext;
328 struct AVDeviceInfoList;
329 struct AVDeviceCapabilitiesQuery;
332 * @defgroup metadata_api Public Metadata API
335 * The metadata API allows libavformat to export metadata tags to a client
336 * application when demuxing. Conversely it allows a client application to
337 * set metadata when muxing.
339 * Metadata is exported or set as pairs of key/value strings in the 'metadata'
340 * fields of the AVFormatContext, AVStream, AVChapter and AVProgram structs
341 * using the @ref lavu_dict "AVDictionary" API. Like all strings in FFmpeg,
342 * metadata is assumed to be UTF-8 encoded Unicode. Note that metadata
343 * exported by demuxers isn't checked to be valid UTF-8 in most cases.
345 * Important concepts to keep in mind:
346 * - Keys are unique; there can never be 2 tags with the same key. This is
347 * also meant semantically, i.e., a demuxer should not knowingly produce
348 * several keys that are literally different but semantically identical.
349 * E.g., key=Author5, key=Author6. In this example, all authors must be
350 * placed in the same tag.
351 * - Metadata is flat, not hierarchical; there are no subtags. If you
352 * want to store, e.g., the email address of the child of producer Alice
353 * and actor Bob, that could have key=alice_and_bobs_childs_email_address.
354 * - Several modifiers can be applied to the tag name. This is done by
355 * appending a dash character ('-') and the modifier name in the order
356 * they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng.
357 * - language -- a tag whose value is localized for a particular language
358 * is appended with the ISO 639-2/B 3-letter language code.
359 * For example: Author-ger=Michael, Author-eng=Mike
360 * The original/default language is in the unqualified "Author" tag.
361 * A demuxer should set a default if it sets any translated tag.
362 * - sorting -- a modified version of a tag that should be used for
363 * sorting will have '-sort' appended. E.g. artist="The Beatles",
364 * artist-sort="Beatles, The".
365 * - Some protocols and demuxers support metadata updates. After a successful
366 * call to av_read_packet(), AVFormatContext.event_flags or AVStream.event_flags
367 * will be updated to indicate if metadata changed. In order to detect metadata
368 * changes on a stream, you need to loop through all streams in the AVFormatContext
369 * and check their individual event_flags.
371 * - Demuxers attempt to export metadata in a generic format, however tags
372 * with no generic equivalents are left as they are stored in the container.
373 * Follows a list of generic tag names:
376 album -- name of the set this work belongs to
377 album_artist -- main creator of the set/album, if different from artist.
378 e.g. "Various Artists" for compilation albums.
379 artist -- main creator of the work
380 comment -- any additional description of the file.
381 composer -- who composed the work, if different from artist.
382 copyright -- name of copyright holder.
383 creation_time-- date when the file was created, preferably in ISO 8601.
384 date -- date when the work was created, preferably in ISO 8601.
385 disc -- number of a subset, e.g. disc in a multi-disc collection.
386 encoder -- name/settings of the software/hardware that produced the file.
387 encoded_by -- person/group who created the file.
388 filename -- original name of the file.
389 genre -- <self-evident>.
390 language -- main language in which the work is performed, preferably
391 in ISO 639-2 format. Multiple languages can be specified by
392 separating them with commas.
393 performer -- artist who performed the work, if different from artist.
394 E.g for "Also sprach Zarathustra", artist would be "Richard
395 Strauss" and performer "London Philharmonic Orchestra".
396 publisher -- name of the label/publisher.
397 service_name -- name of the service in broadcasting (channel name).
398 service_provider -- name of the service provider in broadcasting.
399 title -- name of the work.
400 track -- number of this work in the set, can be in form current/total.
401 variant_bitrate -- the total bitrate of the bitrate variant that the current stream is part of
404 * Look in the examples section for an application example how to use the Metadata API.
409 /* packet functions */
413 * Allocate and read the payload of a packet and initialize its
414 * fields with default values.
416 * @param s associated IO context
418 * @param size desired payload size
419 * @return >0 (read size) if OK, AVERROR_xxx otherwise
421 int av_get_packet(AVIOContext *s, AVPacket *pkt, int size);
425 * Read data and append it to the current content of the AVPacket.
426 * If pkt->size is 0 this is identical to av_get_packet.
427 * Note that this uses av_grow_packet and thus involves a realloc
428 * which is inefficient. Thus this function should only be used
429 * when there is no reasonable way to know (an upper bound of)
432 * @param s associated IO context
434 * @param size amount of data to read
435 * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data
436 * will not be lost even if an error occurs.
438 int av_append_packet(AVIOContext *s, AVPacket *pkt, int size);
440 /*************************************************/
441 /* input/output formats */
446 * This structure contains the data a format has to probe a file.
448 typedef struct AVProbeData {
449 const char *filename;
450 unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
451 int buf_size; /**< Size of buf except extra allocated bytes */
452 const char *mime_type; /**< mime_type, when known. */
455 #define AVPROBE_SCORE_RETRY (AVPROBE_SCORE_MAX/4)
456 #define AVPROBE_SCORE_STREAM_RETRY (AVPROBE_SCORE_MAX/4-1)
458 #define AVPROBE_SCORE_EXTENSION 50 ///< score for file extension
459 #define AVPROBE_SCORE_MIME 75 ///< score for file mime type
460 #define AVPROBE_SCORE_MAX 100 ///< maximum score
462 #define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
464 /// Demuxer will use avio_open, no opened file should be provided by the caller.
465 #define AVFMT_NOFILE 0x0001
466 #define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
467 #define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
468 #define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
469 #define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
470 #define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
471 #define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */
472 #define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */
473 #define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */
474 #define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */
475 #define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fall back on binary search via read_timestamp */
476 #define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fall back on generic search */
477 #define AVFMT_NO_BYTE_SEEK 0x8000 /**< Format does not allow seeking by bytes */
478 #define AVFMT_ALLOW_FLUSH 0x10000 /**< Format allows flushing. If not set, the muxer will not receive a NULL packet in the write_packet function. */
479 #define AVFMT_TS_NONSTRICT 0x20000 /**< Format does not require strictly
480 increasing timestamps, but they must
481 still be monotonic */
482 #define AVFMT_TS_NEGATIVE 0x40000 /**< Format allows muxing negative
483 timestamps. If not set the timestamp
484 will be shifted in av_write_frame and
485 av_interleaved_write_frame so they
487 The user or muxer can override this through
488 AVFormatContext.avoid_negative_ts
491 #define AVFMT_SEEK_TO_PTS 0x4000000 /**< Seeking is based on PTS */
494 * @addtogroup lavf_encoding
497 typedef struct AVOutputFormat {
500 * Descriptive name for the format, meant to be more human-readable
501 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
504 const char *long_name;
505 const char *mime_type;
506 const char *extensions; /**< comma-separated filename extensions */
508 enum AVCodecID audio_codec; /**< default audio codec */
509 enum AVCodecID video_codec; /**< default video codec */
510 enum AVCodecID subtitle_codec; /**< default subtitle codec */
512 * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER,
513 * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
514 * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH,
515 * AVFMT_TS_NONSTRICT, AVFMT_TS_NEGATIVE
520 * List of supported codec_id-codec_tag pairs, ordered by "better
521 * choice first". The arrays are all terminated by AV_CODEC_ID_NONE.
523 const struct AVCodecTag * const *codec_tag;
526 const AVClass *priv_class; ///< AVClass for the private context
528 /*****************************************************************
529 * No fields below this line are part of the public API. They
530 * may not be used outside of libavformat and can be changed and
532 * New public fields should be added right above.
533 *****************************************************************
535 struct AVOutputFormat *next;
537 * size of private data so that it can be allocated in the wrapper
541 int (*write_header)(struct AVFormatContext *);
543 * Write a packet. If AVFMT_ALLOW_FLUSH is set in flags,
544 * pkt can be NULL in order to flush data buffered in the muxer.
545 * When flushing, return 0 if there still is more data to flush,
546 * or 1 if everything was flushed and there is no more buffered
549 int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
550 int (*write_trailer)(struct AVFormatContext *);
552 * Currently only used to set pixel format if not YUV420P.
554 int (*interleave_packet)(struct AVFormatContext *, AVPacket *out,
555 AVPacket *in, int flush);
557 * Test if the given codec can be stored in this container.
559 * @return 1 if the codec is supported, 0 if it is not.
560 * A negative number if unknown.
561 * MKTAG('A', 'P', 'I', 'C') if the codec is only supported as AV_DISPOSITION_ATTACHED_PIC
563 int (*query_codec)(enum AVCodecID id, int std_compliance);
565 void (*get_output_timestamp)(struct AVFormatContext *s, int stream,
566 int64_t *dts, int64_t *wall);
568 * Allows sending messages from application to device.
570 int (*control_message)(struct AVFormatContext *s, int type,
571 void *data, size_t data_size);
574 * Write an uncoded AVFrame.
576 * See av_write_uncoded_frame() for details.
578 * The library will free *frame afterwards, but the muxer can prevent it
579 * by setting the pointer to NULL.
581 int (*write_uncoded_frame)(struct AVFormatContext *, int stream_index,
582 AVFrame **frame, unsigned flags);
584 * Returns device list with it properties.
585 * @see avdevice_list_devices() for more details.
587 int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
589 * Initialize device capabilities submodule.
590 * @see avdevice_capabilities_create() for more details.
592 int (*create_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
594 * Free device capabilities submodule.
595 * @see avdevice_capabilities_free() for more details.
597 int (*free_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
598 enum AVCodecID data_codec; /**< default data codec */
600 * Initialize format. May allocate data here, and set any AVFormatContext or
601 * AVStream parameters that need to be set before packets are sent.
602 * This method must not write output.
604 * Return 0 if streams were fully configured, 1 if not, negative AVERROR on failure
606 * Any allocations made here must be freed in deinit().
608 int (*init)(struct AVFormatContext *);
610 * Deinitialize format. If present, this is called whenever the muxer is being
611 * destroyed, regardless of whether or not the header has been written.
613 * If a trailer is being written, this is called after write_trailer().
615 * This is called if init() fails as well.
617 void (*deinit)(struct AVFormatContext *);
619 * Set up any necessary bitstream filtering and extract any extra data needed
620 * for the global header.
621 * Return 0 if more packets from this stream must be checked; 1 if not.
623 int (*check_bitstream)(struct AVFormatContext *, const AVPacket *pkt);
630 * @addtogroup lavf_decoding
633 typedef struct AVInputFormat {
635 * A comma separated list of short names for the format. New names
636 * may be appended with a minor bump.
641 * Descriptive name for the format, meant to be more human-readable
642 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
645 const char *long_name;
648 * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
649 * AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
650 * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK, AVFMT_SEEK_TO_PTS.
655 * If extensions are defined, then no probe is done. You should
656 * usually not use extension format guessing because it is not
659 const char *extensions;
661 const struct AVCodecTag * const *codec_tag;
663 const AVClass *priv_class; ///< AVClass for the private context
666 * Comma-separated list of mime types.
667 * It is used check for matching mime types while probing.
668 * @see av_probe_input_format2
670 const char *mime_type;
672 /*****************************************************************
673 * No fields below this line are part of the public API. They
674 * may not be used outside of libavformat and can be changed and
676 * New public fields should be added right above.
677 *****************************************************************
679 struct AVInputFormat *next;
682 * Raw demuxers store their codec ID here.
687 * Size of private data so that it can be allocated in the wrapper.
692 * Tell if a given file has a chance of being parsed as this format.
693 * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
694 * big so you do not have to check for that unless you need more.
696 int (*read_probe)(AVProbeData *);
699 * Read the format header and initialize the AVFormatContext
700 * structure. Return 0 if OK. 'avformat_new_stream' should be
701 * called to create new streams.
703 int (*read_header)(struct AVFormatContext *);
706 * Read one packet and put it in 'pkt'. pts and flags are also
707 * set. 'avformat_new_stream' can be called only if the flag
708 * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
709 * background thread).
710 * @return 0 on success, < 0 on error.
711 * When returning an error, pkt must not have been allocated
712 * or must be freed before returning
714 int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
717 * Close the stream. The AVFormatContext and AVStreams are not
718 * freed by this function
720 int (*read_close)(struct AVFormatContext *);
723 * Seek to a given timestamp relative to the frames in
724 * stream component stream_index.
725 * @param stream_index Must not be -1.
726 * @param flags Selects which direction should be preferred if no exact
727 * match is available.
728 * @return >= 0 on success (but not necessarily the new offset)
730 int (*read_seek)(struct AVFormatContext *,
731 int stream_index, int64_t timestamp, int flags);
734 * Get the next timestamp in stream[stream_index].time_base units.
735 * @return the timestamp or AV_NOPTS_VALUE if an error occurred
737 int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
738 int64_t *pos, int64_t pos_limit);
741 * Start/resume playing - only meaningful if using a network-based format
744 int (*read_play)(struct AVFormatContext *);
747 * Pause playing - only meaningful if using a network-based format
750 int (*read_pause)(struct AVFormatContext *);
753 * Seek to timestamp ts.
754 * Seeking will be done so that the point from which all active streams
755 * can be presented successfully will be closest to ts and within min/max_ts.
756 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
758 int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
761 * Returns device list with it properties.
762 * @see avdevice_list_devices() for more details.
764 int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
767 * Initialize device capabilities submodule.
768 * @see avdevice_capabilities_create() for more details.
770 int (*create_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
773 * Free device capabilities submodule.
774 * @see avdevice_capabilities_free() for more details.
776 int (*free_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
782 enum AVStreamParseType {
784 AVSTREAM_PARSE_FULL, /**< full parsing and repack */
785 AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
786 AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
787 AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
788 AVSTREAM_PARSE_FULL_RAW, /**< full parsing and repack with timestamp and position generation by parser for raw
789 this assumes that each packet in the file contains no demuxer level headers and
790 just codec level data, otherwise position generation would fail */
793 typedef struct AVIndexEntry {
795 int64_t timestamp; /**<
796 * Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are available
797 * when seeking to this entry. That means preferable PTS on keyframe based formats.
798 * But demuxers can choose to store a different timestamp, if it is more convenient for the implementation or nothing better
801 #define AVINDEX_KEYFRAME 0x0001
802 #define AVINDEX_DISCARD_FRAME 0x0002 /**
803 * Flag is used to indicate which frame should be discarded after decoding.
806 int size:30; //Yeah, trying to keep the size of this small to reduce memory requirements (it is 24 vs. 32 bytes due to possible 8-byte alignment).
807 int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
810 #define AV_DISPOSITION_DEFAULT 0x0001
811 #define AV_DISPOSITION_DUB 0x0002
812 #define AV_DISPOSITION_ORIGINAL 0x0004
813 #define AV_DISPOSITION_COMMENT 0x0008
814 #define AV_DISPOSITION_LYRICS 0x0010
815 #define AV_DISPOSITION_KARAOKE 0x0020
818 * Track should be used during playback by default.
819 * Useful for subtitle track that should be displayed
820 * even when user did not explicitly ask for subtitles.
822 #define AV_DISPOSITION_FORCED 0x0040
823 #define AV_DISPOSITION_HEARING_IMPAIRED 0x0080 /**< stream for hearing impaired audiences */
824 #define AV_DISPOSITION_VISUAL_IMPAIRED 0x0100 /**< stream for visual impaired audiences */
825 #define AV_DISPOSITION_CLEAN_EFFECTS 0x0200 /**< stream without voice */
827 * The stream is stored in the file as an attached picture/"cover art" (e.g.
828 * APIC frame in ID3v2). The first (usually only) packet associated with it
829 * will be returned among the first few packets read from the file unless
830 * seeking takes place. It can also be accessed at any time in
831 * AVStream.attached_pic.
833 #define AV_DISPOSITION_ATTACHED_PIC 0x0400
835 * The stream is sparse, and contains thumbnail images, often corresponding
836 * to chapter markers. Only ever used with AV_DISPOSITION_ATTACHED_PIC.
838 #define AV_DISPOSITION_TIMED_THUMBNAILS 0x0800
840 typedef struct AVStreamInternal AVStreamInternal;
843 * To specify text track kind (different from subtitles default).
845 #define AV_DISPOSITION_CAPTIONS 0x10000
846 #define AV_DISPOSITION_DESCRIPTIONS 0x20000
847 #define AV_DISPOSITION_METADATA 0x40000
848 #define AV_DISPOSITION_DEPENDENT 0x80000 ///< dependent audio stream (mix_type=0 in mpegts)
849 #define AV_DISPOSITION_STILL_IMAGE 0x100000 ///< still images in video stream (still_picture_flag=1 in mpegts)
852 * Options for behavior on timestamp wrap detection.
854 #define AV_PTS_WRAP_IGNORE 0 ///< ignore the wrap
855 #define AV_PTS_WRAP_ADD_OFFSET 1 ///< add the format specific offset on wrap detection
856 #define AV_PTS_WRAP_SUB_OFFSET -1 ///< subtract the format specific offset on wrap detection
860 * New fields can be added to the end with minor version bumps.
861 * Removal, reordering and changes to existing fields require a major
863 * sizeof(AVStream) must not be used outside libav*.
865 typedef struct AVStream {
866 int index; /**< stream index in AVFormatContext */
868 * Format-specific stream ID.
869 * decoding: set by libavformat
870 * encoding: set by the user, replaced by libavformat if left unset
873 #if FF_API_LAVF_AVCTX
875 * @deprecated use the codecpar struct instead
878 AVCodecContext *codec;
883 * This is the fundamental unit of time (in seconds) in terms
884 * of which frame timestamps are represented.
886 * decoding: set by libavformat
887 * encoding: May be set by the caller before avformat_write_header() to
888 * provide a hint to the muxer about the desired timebase. In
889 * avformat_write_header(), the muxer will overwrite this field
890 * with the timebase that will actually be used for the timestamps
891 * written into the file (which may or may not be related to the
892 * user-provided one, depending on the format).
894 AVRational time_base;
897 * Decoding: pts of the first frame of the stream in presentation order, in stream time base.
898 * Only set this if you are absolutely 100% sure that the value you set
899 * it to really is the pts of the first frame.
900 * This may be undefined (AV_NOPTS_VALUE).
901 * @note The ASF header does NOT contain a correct start_time the ASF
902 * demuxer must NOT set this.
907 * Decoding: duration of the stream, in stream time base.
908 * If a source file does not specify a duration, but does specify
909 * a bitrate, this value will be estimated from bitrate and file size.
911 * Encoding: May be set by the caller before avformat_write_header() to
912 * provide a hint to the muxer about the estimated duration.
916 int64_t nb_frames; ///< number of frames in this stream if known or 0
918 int disposition; /**< AV_DISPOSITION_* bit field */
920 enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
923 * sample aspect ratio (0 if unknown)
924 * - encoding: Set by user.
925 * - decoding: Set by libavformat.
927 AVRational sample_aspect_ratio;
929 AVDictionary *metadata;
934 * - demuxing: May be set by libavformat when creating the stream or in
935 * avformat_find_stream_info().
936 * - muxing: May be set by the caller before avformat_write_header().
938 AVRational avg_frame_rate;
941 * For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet
942 * will contain the attached picture.
944 * decoding: set by libavformat, must not be modified by the caller.
947 AVPacket attached_pic;
950 * An array of side data that applies to the whole stream (i.e. the
951 * container does not allow it to change between packets).
953 * There may be no overlap between the side data in this array and side data
954 * in the packets. I.e. a given side data is either exported by the muxer
955 * (demuxing) / set by the caller (muxing) in this array, then it never
956 * appears in the packets, or the side data is exported / sent through
957 * the packets (always in the first packet where the value becomes known or
958 * changes), then it does not appear in this array.
960 * - demuxing: Set by libavformat when the stream is created.
961 * - muxing: May be set by the caller before avformat_write_header().
963 * Freed by libavformat in avformat_free_context().
965 * @see av_format_inject_global_side_data()
967 AVPacketSideData *side_data;
969 * The number of elements in the AVStream.side_data array.
974 * Flags for the user to detect events happening on the stream. Flags must
975 * be cleared by the user once the event has been handled.
976 * A combination of AVSTREAM_EVENT_FLAG_*.
979 #define AVSTREAM_EVENT_FLAG_METADATA_UPDATED 0x0001 ///< The call resulted in updated metadata.
982 * Real base framerate of the stream.
983 * This is the lowest framerate with which all timestamps can be
984 * represented accurately (it is the least common multiple of all
985 * framerates in the stream). Note, this value is just a guess!
986 * For example, if the time base is 1/90000 and all frames have either
987 * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
989 AVRational r_frame_rate;
991 #if FF_API_LAVF_FFSERVER
993 * String containing pairs of key and values describing recommended encoder configuration.
994 * Pairs are separated by ','.
995 * Keys are separated from values by '='.
1000 char *recommended_encoder_configuration;
1004 * Codec parameters associated with this stream. Allocated and freed by
1005 * libavformat in avformat_new_stream() and avformat_free_context()
1008 * - demuxing: filled by libavformat on stream creation or in
1009 * avformat_find_stream_info()
1010 * - muxing: filled by the caller before avformat_write_header()
1012 AVCodecParameters *codecpar;
1014 /*****************************************************************
1015 * All fields below this line are not part of the public API. They
1016 * may not be used outside of libavformat and can be changed and
1018 * Internal note: be aware that physically removing these fields
1019 * will break ABI. Replace removed fields with dummy fields, and
1020 * add new fields to AVStreamInternal.
1021 *****************************************************************
1024 #define MAX_STD_TIMEBASES (30*12+30+3+6)
1026 * Stream information used internally by avformat_find_stream_info()
1030 int64_t duration_gcd;
1032 int64_t rfps_duration_sum;
1033 double (*duration_error)[2][MAX_STD_TIMEBASES];
1034 int64_t codec_info_duration;
1035 int64_t codec_info_duration_fields;
1036 int frame_delay_evidence;
1039 * 0 -> decoder has not been searched for yet.
1040 * >0 -> decoder found
1041 * <0 -> decoder with codec_id == -found_decoder has not been found
1045 int64_t last_duration;
1048 * Those are used for average framerate estimation.
1050 int64_t fps_first_dts;
1051 int fps_first_dts_idx;
1052 int64_t fps_last_dts;
1053 int fps_last_dts_idx;
1057 int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
1059 // Timestamp generation support:
1061 * Timestamp corresponding to the last dts sync point.
1063 * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
1064 * a DTS is received from the underlying container. Otherwise set to
1065 * AV_NOPTS_VALUE by default.
1069 int64_t last_IP_pts;
1070 int last_IP_duration;
1073 * Number of packets to buffer for codec probing
1078 * Number of frames that have been demuxed during avformat_find_stream_info()
1080 int codec_info_nb_frames;
1082 /* av_read_frame() support */
1083 enum AVStreamParseType need_parsing;
1084 struct AVCodecParserContext *parser;
1087 * last packet in packet_buffer for this stream when muxing.
1089 struct AVPacketList *last_in_packet_buffer;
1090 AVProbeData probe_data;
1091 #define MAX_REORDER_DELAY 16
1092 int64_t pts_buffer[MAX_REORDER_DELAY+1];
1094 AVIndexEntry *index_entries; /**< Only used if the format does not
1095 support seeking natively. */
1096 int nb_index_entries;
1097 unsigned int index_entries_allocated_size;
1101 * This is the MPEG-TS stream identifier +1
1104 int stream_identifier;
1106 int64_t interleaver_chunk_size;
1107 int64_t interleaver_chunk_duration;
1110 * stream probing state
1111 * -1 -> probing finished
1112 * 0 -> no probing requested
1113 * rest -> perform probing with request_probe being the minimum score to accept.
1114 * NOT PART OF PUBLIC API
1118 * Indicates that everything up to the next keyframe
1119 * should be discarded.
1121 int skip_to_keyframe;
1124 * Number of samples to skip at the start of the frame decoded from the next packet.
1129 * If not 0, the number of samples that should be skipped from the start of
1130 * the stream (the samples are removed from packets with pts==0, which also
1131 * assumes negative timestamps do not happen).
1132 * Intended for use with formats such as mp3 with ad-hoc gapless audio
1135 int64_t start_skip_samples;
1138 * If not 0, the first audio sample that should be discarded from the stream.
1139 * This is broken by design (needs global sample count), but can't be
1140 * avoided for broken by design formats such as mp3 with ad-hoc gapless
1143 int64_t first_discard_sample;
1146 * The sample after last sample that is intended to be discarded after
1147 * first_discard_sample. Works on frame boundaries only. Used to prevent
1148 * early EOF if the gapless info is broken (considered concatenated mp3s).
1150 int64_t last_discard_sample;
1153 * Number of internally decoded frames, used internally in libavformat, do not access
1154 * its lifetime differs from info which is why it is not in that structure.
1156 int nb_decoded_frames;
1159 * Timestamp offset added to timestamps before muxing
1160 * NOT PART OF PUBLIC API
1162 int64_t mux_ts_offset;
1165 * Internal data to check for wrapping of the time stamp
1167 int64_t pts_wrap_reference;
1170 * Options for behavior, when a wrap is detected.
1172 * Defined by AV_PTS_WRAP_ values.
1174 * If correction is enabled, there are two possibilities:
1175 * If the first time stamp is near the wrap point, the wrap offset
1176 * will be subtracted, which will create negative time stamps.
1177 * Otherwise the offset will be added.
1179 int pts_wrap_behavior;
1182 * Internal data to prevent doing update_initial_durations() twice
1184 int update_initial_durations_done;
1187 * Internal data to generate dts from pts
1189 int64_t pts_reorder_error[MAX_REORDER_DELAY+1];
1190 uint8_t pts_reorder_error_count[MAX_REORDER_DELAY+1];
1193 * Internal data to analyze DTS and detect faulty mpeg streams
1195 int64_t last_dts_for_order_check;
1196 uint8_t dts_ordered;
1197 uint8_t dts_misordered;
1200 * Internal data to inject global side data
1202 int inject_global_side_data;
1205 * display aspect ratio (0 if unknown)
1206 * - encoding: unused
1207 * - decoding: Set by libavformat to calculate sample_aspect_ratio internally
1209 AVRational display_aspect_ratio;
1212 * An opaque field for libavformat internal usage.
1213 * Must not be accessed in any way by callers.
1215 AVStreamInternal *internal;
1218 #if FF_API_FORMAT_GET_SET
1220 * Accessors for some AVStream fields. These used to be provided for ABI
1221 * compatibility, and do not need to be used anymore.
1223 attribute_deprecated
1224 AVRational av_stream_get_r_frame_rate(const AVStream *s);
1225 attribute_deprecated
1226 void av_stream_set_r_frame_rate(AVStream *s, AVRational r);
1227 #if FF_API_LAVF_FFSERVER
1228 attribute_deprecated
1229 char* av_stream_get_recommended_encoder_configuration(const AVStream *s);
1230 attribute_deprecated
1231 void av_stream_set_recommended_encoder_configuration(AVStream *s, char *configuration);
1235 struct AVCodecParserContext *av_stream_get_parser(const AVStream *s);
1238 * Returns the pts of the last muxed packet + its duration
1240 * the retuned value is undefined when used with a demuxer.
1242 int64_t av_stream_get_end_pts(const AVStream *st);
1244 #define AV_PROGRAM_RUNNING 1
1247 * New fields can be added to the end with minor version bumps.
1248 * Removal, reordering and changes to existing fields require a major
1250 * sizeof(AVProgram) must not be used outside libav*.
1252 typedef struct AVProgram {
1255 enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
1256 unsigned int *stream_index;
1257 unsigned int nb_stream_indexes;
1258 AVDictionary *metadata;
1264 /*****************************************************************
1265 * All fields below this line are not part of the public API. They
1266 * may not be used outside of libavformat and can be changed and
1268 * New public fields should be added right above.
1269 *****************************************************************
1274 int64_t pts_wrap_reference; ///< reference dts for wrap detection
1275 int pts_wrap_behavior; ///< behavior on wrap detection
1278 #define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
1279 (streams are added dynamically) */
1280 #define AVFMTCTX_UNSEEKABLE 0x0002 /**< signal that the stream is definitely
1281 not seekable, and attempts to call the
1282 seek function will fail. For some
1283 network protocols (e.g. HLS), this can
1284 change dynamically at runtime. */
1286 typedef struct AVChapter {
1287 int id; ///< unique ID to identify the chapter
1288 AVRational time_base; ///< time base in which the start/end timestamps are specified
1289 int64_t start, end; ///< chapter start/end time in time_base units
1290 AVDictionary *metadata;
1295 * Callback used by devices to communicate with application.
1297 typedef int (*av_format_control_message)(struct AVFormatContext *s, int type,
1298 void *data, size_t data_size);
1300 typedef int (*AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags,
1301 const AVIOInterruptCB *int_cb, AVDictionary **options);
1304 * The duration of a video can be estimated through various ways, and this enum can be used
1305 * to know how the duration was estimated.
1307 enum AVDurationEstimationMethod {
1308 AVFMT_DURATION_FROM_PTS, ///< Duration accurately estimated from PTSes
1309 AVFMT_DURATION_FROM_STREAM, ///< Duration estimated from a stream with a known duration
1310 AVFMT_DURATION_FROM_BITRATE ///< Duration estimated from bitrate (less accurate)
1313 typedef struct AVFormatInternal AVFormatInternal;
1316 * Format I/O context.
1317 * New fields can be added to the end with minor version bumps.
1318 * Removal, reordering and changes to existing fields require a major
1320 * sizeof(AVFormatContext) must not be used outside libav*, use
1321 * avformat_alloc_context() to create an AVFormatContext.
1323 * Fields can be accessed through AVOptions (av_opt*),
1324 * the name string used matches the associated command line parameter name and
1325 * can be found in libavformat/options_table.h.
1326 * The AVOption/command line parameter names differ in some cases from the C
1327 * structure field names for historic reasons or brevity.
1329 typedef struct AVFormatContext {
1331 * A class for logging and @ref avoptions. Set by avformat_alloc_context().
1332 * Exports (de)muxer private options if they exist.
1334 const AVClass *av_class;
1337 * The input container format.
1339 * Demuxing only, set by avformat_open_input().
1341 struct AVInputFormat *iformat;
1344 * The output container format.
1346 * Muxing only, must be set by the caller before avformat_write_header().
1348 struct AVOutputFormat *oformat;
1351 * Format private data. This is an AVOptions-enabled struct
1352 * if and only if iformat/oformat.priv_class is not NULL.
1354 * - muxing: set by avformat_write_header()
1355 * - demuxing: set by avformat_open_input()
1362 * - demuxing: either set by the user before avformat_open_input() (then
1363 * the user must close it manually) or set by avformat_open_input().
1364 * - muxing: set by the user before avformat_write_header(). The caller must
1365 * take care of closing / freeing the IO context.
1367 * Do NOT set this field if AVFMT_NOFILE flag is set in
1368 * iformat/oformat.flags. In such a case, the (de)muxer will handle
1369 * I/O in some other way and this field will be NULL.
1375 * Flags signalling stream properties. A combination of AVFMTCTX_*.
1376 * Set by libavformat.
1381 * Number of elements in AVFormatContext.streams.
1383 * Set by avformat_new_stream(), must not be modified by any other code.
1385 unsigned int nb_streams;
1387 * A list of all streams in the file. New streams are created with
1388 * avformat_new_stream().
1390 * - demuxing: streams are created by libavformat in avformat_open_input().
1391 * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
1392 * appear in av_read_frame().
1393 * - muxing: streams are created by the user before avformat_write_header().
1395 * Freed by libavformat in avformat_free_context().
1399 #if FF_API_FORMAT_FILENAME
1401 * input or output filename
1403 * - demuxing: set by avformat_open_input()
1404 * - muxing: may be set by the caller before avformat_write_header()
1406 * @deprecated Use url instead.
1408 attribute_deprecated
1409 char filename[1024];
1413 * input or output URL. Unlike the old filename field, this field has no
1414 * length restriction.
1416 * - demuxing: set by avformat_open_input(), initialized to an empty
1417 * string if url parameter was NULL in avformat_open_input().
1418 * - muxing: may be set by the caller before calling avformat_write_header()
1419 * (or avformat_init_output() if that is called first) to a string
1420 * which is freeable by av_free(). Set to an empty string if it
1421 * was NULL in avformat_init_output().
1423 * Freed by libavformat in avformat_free_context().
1428 * Position of the first frame of the component, in
1429 * AV_TIME_BASE fractional seconds. NEVER set this value directly:
1430 * It is deduced from the AVStream values.
1432 * Demuxing only, set by libavformat.
1437 * Duration of the stream, in AV_TIME_BASE fractional
1438 * seconds. Only set this value if you know none of the individual stream
1439 * durations and also do not set any of them. This is deduced from the
1440 * AVStream values if not set.
1442 * Demuxing only, set by libavformat.
1447 * Total stream bitrate in bit/s, 0 if not
1448 * available. Never set it directly if the file_size and the
1449 * duration are known as FFmpeg can compute it automatically.
1453 unsigned int packet_size;
1457 * Flags modifying the (de)muxer behaviour. A combination of AVFMT_FLAG_*.
1458 * Set by the user before avformat_open_input() / avformat_write_header().
1461 #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
1462 #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
1463 #define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
1464 #define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
1465 #define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
1466 #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
1467 #define AVFMT_FLAG_NOBUFFER 0x0040 ///< Do not buffer frames when possible
1468 #define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
1469 #define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted
1470 #define AVFMT_FLAG_FLUSH_PACKETS 0x0200 ///< Flush the AVIOContext every packet.
1472 * When muxing, try to avoid writing any random/volatile data to the output.
1473 * This includes any random IDs, real-time timestamps/dates, muxer version, etc.
1475 * This flag is mainly intended for testing.
1477 #define AVFMT_FLAG_BITEXACT 0x0400
1478 #define AVFMT_FLAG_MP4A_LATM 0x8000 ///< Enable RTP MP4A-LATM payload
1479 #define AVFMT_FLAG_SORT_DTS 0x10000 ///< try to interleave outputted packets by dts (using this flag can slow demuxing down)
1480 #define AVFMT_FLAG_PRIV_OPT 0x20000 ///< Enable use of private options by delaying codec open (this could be made default once all code is converted)
1481 #if FF_API_LAVF_KEEPSIDE_FLAG
1482 #define AVFMT_FLAG_KEEP_SIDE_DATA 0x40000 ///< Deprecated, does nothing.
1484 #define AVFMT_FLAG_FAST_SEEK 0x80000 ///< Enable fast, but inaccurate seeks for some formats
1485 #define AVFMT_FLAG_SHORTEST 0x100000 ///< Stop muxing when the shortest stream stops.
1486 #define AVFMT_FLAG_AUTO_BSF 0x200000 ///< Add bitstream filters as requested by the muxer
1489 * Maximum size of the data read from input for determining
1490 * the input container format.
1491 * Demuxing only, set by the caller before avformat_open_input().
1496 * Maximum duration (in AV_TIME_BASE units) of the data read
1497 * from input in avformat_find_stream_info().
1498 * Demuxing only, set by the caller before avformat_find_stream_info().
1499 * Can be set to 0 to let avformat choose using a heuristic.
1501 int64_t max_analyze_duration;
1506 unsigned int nb_programs;
1507 AVProgram **programs;
1510 * Forced video codec_id.
1511 * Demuxing: Set by user.
1513 enum AVCodecID video_codec_id;
1516 * Forced audio codec_id.
1517 * Demuxing: Set by user.
1519 enum AVCodecID audio_codec_id;
1522 * Forced subtitle codec_id.
1523 * Demuxing: Set by user.
1525 enum AVCodecID subtitle_codec_id;
1528 * Maximum amount of memory in bytes to use for the index of each stream.
1529 * If the index exceeds this size, entries will be discarded as
1530 * needed to maintain a smaller size. This can lead to slower or less
1531 * accurate seeking (depends on demuxer).
1532 * Demuxers for which a full in-memory index is mandatory will ignore
1535 * - demuxing: set by user
1537 unsigned int max_index_size;
1540 * Maximum amount of memory in bytes to use for buffering frames
1541 * obtained from realtime capture devices.
1543 unsigned int max_picture_buffer;
1546 * Number of chapters in AVChapter array.
1547 * When muxing, chapters are normally written in the file header,
1548 * so nb_chapters should normally be initialized before write_header
1549 * is called. Some muxers (e.g. mov and mkv) can also write chapters
1550 * in the trailer. To write chapters in the trailer, nb_chapters
1551 * must be zero when write_header is called and non-zero when
1552 * write_trailer is called.
1553 * - muxing: set by user
1554 * - demuxing: set by libavformat
1556 unsigned int nb_chapters;
1557 AVChapter **chapters;
1560 * Metadata that applies to the whole file.
1562 * - demuxing: set by libavformat in avformat_open_input()
1563 * - muxing: may be set by the caller before avformat_write_header()
1565 * Freed by libavformat in avformat_free_context().
1567 AVDictionary *metadata;
1570 * Start time of the stream in real world time, in microseconds
1571 * since the Unix epoch (00:00 1st January 1970). That is, pts=0 in the
1572 * stream was captured at this real world time.
1573 * - muxing: Set by the caller before avformat_write_header(). If set to
1574 * either 0 or AV_NOPTS_VALUE, then the current wall-time will
1576 * - demuxing: Set by libavformat. AV_NOPTS_VALUE if unknown. Note that
1577 * the value may become known after some number of frames
1578 * have been received.
1580 int64_t start_time_realtime;
1583 * The number of frames used for determining the framerate in
1584 * avformat_find_stream_info().
1585 * Demuxing only, set by the caller before avformat_find_stream_info().
1590 * Error recognition; higher values will detect more errors but may
1591 * misdetect some more or less valid parts as errors.
1592 * Demuxing only, set by the caller before avformat_open_input().
1594 int error_recognition;
1597 * Custom interrupt callbacks for the I/O layer.
1599 * demuxing: set by the user before avformat_open_input().
1600 * muxing: set by the user before avformat_write_header()
1601 * (mainly useful for AVFMT_NOFILE formats). The callback
1602 * should also be passed to avio_open2() if it's used to
1605 AVIOInterruptCB interrupt_callback;
1608 * Flags to enable debugging.
1611 #define FF_FDEBUG_TS 0x0001
1614 * Maximum buffering duration for interleaving.
1616 * To ensure all the streams are interleaved correctly,
1617 * av_interleaved_write_frame() will wait until it has at least one packet
1618 * for each stream before actually writing any packets to the output file.
1619 * When some streams are "sparse" (i.e. there are large gaps between
1620 * successive packets), this can result in excessive buffering.
1622 * This field specifies the maximum difference between the timestamps of the
1623 * first and the last packet in the muxing queue, above which libavformat
1624 * will output a packet regardless of whether it has queued a packet for all
1627 * Muxing only, set by the caller before avformat_write_header().
1629 int64_t max_interleave_delta;
1632 * Allow non-standard and experimental extension
1633 * @see AVCodecContext.strict_std_compliance
1635 int strict_std_compliance;
1638 * Flags for the user to detect events happening on the file. Flags must
1639 * be cleared by the user once the event has been handled.
1640 * A combination of AVFMT_EVENT_FLAG_*.
1643 #define AVFMT_EVENT_FLAG_METADATA_UPDATED 0x0001 ///< The call resulted in updated metadata.
1646 * Maximum number of packets to read while waiting for the first timestamp.
1652 * Avoid negative timestamps during muxing.
1653 * Any value of the AVFMT_AVOID_NEG_TS_* constants.
1654 * Note, this only works when using av_interleaved_write_frame. (interleave_packet_per_dts is in use)
1655 * - muxing: Set by user
1656 * - demuxing: unused
1658 int avoid_negative_ts;
1659 #define AVFMT_AVOID_NEG_TS_AUTO -1 ///< Enabled when required by target format
1660 #define AVFMT_AVOID_NEG_TS_MAKE_NON_NEGATIVE 1 ///< Shift timestamps so they are non negative
1661 #define AVFMT_AVOID_NEG_TS_MAKE_ZERO 2 ///< Shift timestamps so that they start at 0
1664 * Transport stream id.
1665 * This will be moved into demuxer private options. Thus no API/ABI compatibility
1670 * Audio preload in microseconds.
1671 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1672 * - encoding: Set by user
1673 * - decoding: unused
1678 * Max chunk time in microseconds.
1679 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1680 * - encoding: Set by user
1681 * - decoding: unused
1683 int max_chunk_duration;
1686 * Max chunk size in bytes
1687 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1688 * - encoding: Set by user
1689 * - decoding: unused
1694 * forces the use of wallclock timestamps as pts/dts of packets
1695 * This has undefined results in the presence of B frames.
1696 * - encoding: unused
1697 * - decoding: Set by user
1699 int use_wallclock_as_timestamps;
1702 * avio flags, used to force AVIO_FLAG_DIRECT.
1703 * - encoding: unused
1704 * - decoding: Set by user
1709 * The duration field can be estimated through various ways, and this field can be used
1710 * to know how the duration was estimated.
1711 * - encoding: unused
1712 * - decoding: Read by user
1714 enum AVDurationEstimationMethod duration_estimation_method;
1717 * Skip initial bytes when opening stream
1718 * - encoding: unused
1719 * - decoding: Set by user
1721 int64_t skip_initial_bytes;
1724 * Correct single timestamp overflows
1725 * - encoding: unused
1726 * - decoding: Set by user
1728 unsigned int correct_ts_overflow;
1731 * Force seeking to any (also non key) frames.
1732 * - encoding: unused
1733 * - decoding: Set by user
1738 * Flush the I/O context after each packet.
1739 * - encoding: Set by user
1740 * - decoding: unused
1745 * format probing score.
1746 * The maximal score is AVPROBE_SCORE_MAX, its set when the demuxer probes
1748 * - encoding: unused
1749 * - decoding: set by avformat, read by user
1754 * number of bytes to read maximally to identify format.
1755 * - encoding: unused
1756 * - decoding: set by user
1758 int format_probesize;
1761 * ',' separated list of allowed decoders.
1762 * If NULL then all are allowed
1763 * - encoding: unused
1764 * - decoding: set by user
1766 char *codec_whitelist;
1769 * ',' separated list of allowed demuxers.
1770 * If NULL then all are allowed
1771 * - encoding: unused
1772 * - decoding: set by user
1774 char *format_whitelist;
1777 * An opaque field for libavformat internal usage.
1778 * Must not be accessed in any way by callers.
1780 AVFormatInternal *internal;
1783 * IO repositioned flag.
1784 * This is set by avformat when the underlaying IO context read pointer
1785 * is repositioned, for example when doing byte based seeking.
1786 * Demuxers can use the flag to detect such changes.
1788 int io_repositioned;
1791 * Forced video codec.
1792 * This allows forcing a specific decoder, even when there are multiple with
1793 * the same codec_id.
1794 * Demuxing: Set by user
1796 AVCodec *video_codec;
1799 * Forced audio codec.
1800 * This allows forcing a specific decoder, even when there are multiple with
1801 * the same codec_id.
1802 * Demuxing: Set by user
1804 AVCodec *audio_codec;
1807 * Forced subtitle codec.
1808 * This allows forcing a specific decoder, even when there are multiple with
1809 * the same codec_id.
1810 * Demuxing: Set by user
1812 AVCodec *subtitle_codec;
1815 * Forced data codec.
1816 * This allows forcing a specific decoder, even when there are multiple with
1817 * the same codec_id.
1818 * Demuxing: Set by user
1820 AVCodec *data_codec;
1823 * Number of bytes to be written as padding in a metadata header.
1825 * Muxing: Set by user via av_format_set_metadata_header_padding.
1827 int metadata_header_padding;
1831 * This is a place for some private data of the user.
1836 * Callback used by devices to communicate with application.
1838 av_format_control_message control_message_cb;
1841 * Output timestamp offset, in microseconds.
1842 * Muxing: set by user
1844 int64_t output_ts_offset;
1847 * dump format separator.
1848 * can be ", " or "\n " or anything else
1849 * - muxing: Set by user.
1850 * - demuxing: Set by user.
1852 uint8_t *dump_separator;
1855 * Forced Data codec_id.
1856 * Demuxing: Set by user.
1858 enum AVCodecID data_codec_id;
1860 #if FF_API_OLD_OPEN_CALLBACKS
1862 * Called to open further IO contexts when needed for demuxing.
1864 * This can be set by the user application to perform security checks on
1865 * the URLs before opening them.
1866 * The function should behave like avio_open2(), AVFormatContext is provided
1867 * as contextual information and to reach AVFormatContext.opaque.
1869 * If NULL then some simple checks are used together with avio_open2().
1871 * Must not be accessed directly from outside avformat.
1872 * @See av_format_set_open_cb()
1874 * Demuxing: Set by user.
1876 * @deprecated Use io_open and io_close.
1878 attribute_deprecated
1879 int (*open_cb)(struct AVFormatContext *s, AVIOContext **p, const char *url, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options);
1883 * ',' separated list of allowed protocols.
1884 * - encoding: unused
1885 * - decoding: set by user
1887 char *protocol_whitelist;
1890 * A callback for opening new IO streams.
1892 * Whenever a muxer or a demuxer needs to open an IO stream (typically from
1893 * avformat_open_input() for demuxers, but for certain formats can happen at
1894 * other times as well), it will call this callback to obtain an IO context.
1896 * @param s the format context
1897 * @param pb on success, the newly opened IO context should be returned here
1898 * @param url the url to open
1899 * @param flags a combination of AVIO_FLAG_*
1900 * @param options a dictionary of additional options, with the same
1901 * semantics as in avio_open2()
1902 * @return 0 on success, a negative AVERROR code on failure
1904 * @note Certain muxers and demuxers do nesting, i.e. they open one or more
1905 * additional internal format contexts. Thus the AVFormatContext pointer
1906 * passed to this callback may be different from the one facing the caller.
1907 * It will, however, have the same 'opaque' field.
1909 int (*io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url,
1910 int flags, AVDictionary **options);
1913 * A callback for closing the streams opened with AVFormatContext.io_open().
1915 void (*io_close)(struct AVFormatContext *s, AVIOContext *pb);
1918 * ',' separated list of disallowed protocols.
1919 * - encoding: unused
1920 * - decoding: set by user
1922 char *protocol_blacklist;
1925 * The maximum number of streams.
1926 * - encoding: unused
1927 * - decoding: set by user
1932 * Skip duration calcuation in estimate_timings_from_pts.
1933 * - encoding: unused
1934 * - decoding: set by user
1936 int skip_estimate_duration_from_pts;
1939 #if FF_API_FORMAT_GET_SET
1941 * Accessors for some AVFormatContext fields. These used to be provided for ABI
1942 * compatibility, and do not need to be used anymore.
1944 attribute_deprecated
1945 int av_format_get_probe_score(const AVFormatContext *s);
1946 attribute_deprecated
1947 AVCodec * av_format_get_video_codec(const AVFormatContext *s);
1948 attribute_deprecated
1949 void av_format_set_video_codec(AVFormatContext *s, AVCodec *c);
1950 attribute_deprecated
1951 AVCodec * av_format_get_audio_codec(const AVFormatContext *s);
1952 attribute_deprecated
1953 void av_format_set_audio_codec(AVFormatContext *s, AVCodec *c);
1954 attribute_deprecated
1955 AVCodec * av_format_get_subtitle_codec(const AVFormatContext *s);
1956 attribute_deprecated
1957 void av_format_set_subtitle_codec(AVFormatContext *s, AVCodec *c);
1958 attribute_deprecated
1959 AVCodec * av_format_get_data_codec(const AVFormatContext *s);
1960 attribute_deprecated
1961 void av_format_set_data_codec(AVFormatContext *s, AVCodec *c);
1962 attribute_deprecated
1963 int av_format_get_metadata_header_padding(const AVFormatContext *s);
1964 attribute_deprecated
1965 void av_format_set_metadata_header_padding(AVFormatContext *s, int c);
1966 attribute_deprecated
1967 void * av_format_get_opaque(const AVFormatContext *s);
1968 attribute_deprecated
1969 void av_format_set_opaque(AVFormatContext *s, void *opaque);
1970 attribute_deprecated
1971 av_format_control_message av_format_get_control_message_cb(const AVFormatContext *s);
1972 attribute_deprecated
1973 void av_format_set_control_message_cb(AVFormatContext *s, av_format_control_message callback);
1974 #if FF_API_OLD_OPEN_CALLBACKS
1975 attribute_deprecated AVOpenCallback av_format_get_open_cb(const AVFormatContext *s);
1976 attribute_deprecated void av_format_set_open_cb(AVFormatContext *s, AVOpenCallback callback);
1981 * This function will cause global side data to be injected in the next packet
1982 * of each stream as well as after any subsequent seek.
1984 void av_format_inject_global_side_data(AVFormatContext *s);
1987 * Returns the method used to set ctx->duration.
1989 * @return AVFMT_DURATION_FROM_PTS, AVFMT_DURATION_FROM_STREAM, or AVFMT_DURATION_FROM_BITRATE.
1991 enum AVDurationEstimationMethod av_fmt_ctx_get_duration_estimation_method(const AVFormatContext* ctx);
1993 typedef struct AVPacketList {
1995 struct AVPacketList *next;
2000 * @defgroup lavf_core Core functions
2003 * Functions for querying libavformat capabilities, allocating core structures,
2009 * Return the LIBAVFORMAT_VERSION_INT constant.
2011 unsigned avformat_version(void);
2014 * Return the libavformat build-time configuration.
2016 const char *avformat_configuration(void);
2019 * Return the libavformat license.
2021 const char *avformat_license(void);
2025 * Initialize libavformat and register all the muxers, demuxers and
2026 * protocols. If you do not call this function, then you can select
2027 * exactly which formats you want to support.
2029 * @see av_register_input_format()
2030 * @see av_register_output_format()
2032 attribute_deprecated
2033 void av_register_all(void);
2035 attribute_deprecated
2036 void av_register_input_format(AVInputFormat *format);
2037 attribute_deprecated
2038 void av_register_output_format(AVOutputFormat *format);
2042 * Do global initialization of network libraries. This is optional,
2043 * and not recommended anymore.
2045 * This functions only exists to work around thread-safety issues
2046 * with older GnuTLS or OpenSSL libraries. If libavformat is linked
2047 * to newer versions of those libraries, or if you do not use them,
2048 * calling this function is unnecessary. Otherwise, you need to call
2049 * this function before any other threads using them are started.
2051 * This function will be deprecated once support for older GnuTLS and
2052 * OpenSSL libraries is removed, and this function has no purpose
2055 int avformat_network_init(void);
2058 * Undo the initialization done by avformat_network_init. Call it only
2059 * once for each time you called avformat_network_init.
2061 int avformat_network_deinit(void);
2065 * If f is NULL, returns the first registered input format,
2066 * if f is non-NULL, returns the next registered input format after f
2067 * or NULL if f is the last one.
2069 attribute_deprecated
2070 AVInputFormat *av_iformat_next(const AVInputFormat *f);
2073 * If f is NULL, returns the first registered output format,
2074 * if f is non-NULL, returns the next registered output format after f
2075 * or NULL if f is the last one.
2077 attribute_deprecated
2078 AVOutputFormat *av_oformat_next(const AVOutputFormat *f);
2082 * Iterate over all registered muxers.
2084 * @param opaque a pointer where libavformat will store the iteration state. Must
2085 * point to NULL to start the iteration.
2087 * @return the next registered muxer or NULL when the iteration is
2090 const AVOutputFormat *av_muxer_iterate(void **opaque);
2093 * Iterate over all registered demuxers.
2095 * @param opaque a pointer where libavformat will store the iteration state. Must
2096 * point to NULL to start the iteration.
2098 * @return the next registered demuxer or NULL when the iteration is
2101 const AVInputFormat *av_demuxer_iterate(void **opaque);
2104 * Allocate an AVFormatContext.
2105 * avformat_free_context() can be used to free the context and everything
2106 * allocated by the framework within it.
2108 AVFormatContext *avformat_alloc_context(void);
2111 * Free an AVFormatContext and all its streams.
2112 * @param s context to free
2114 void avformat_free_context(AVFormatContext *s);
2117 * Get the AVClass for AVFormatContext. It can be used in combination with
2118 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2120 * @see av_opt_find().
2122 const AVClass *avformat_get_class(void);
2125 * Add a new stream to a media file.
2127 * When demuxing, it is called by the demuxer in read_header(). If the
2128 * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
2129 * be called in read_packet().
2131 * When muxing, should be called by the user before avformat_write_header().
2133 * User is required to call avcodec_close() and avformat_free_context() to
2134 * clean up the allocation by avformat_new_stream().
2136 * @param s media file handle
2137 * @param c If non-NULL, the AVCodecContext corresponding to the new stream
2138 * will be initialized to use this codec. This is needed for e.g. codec-specific
2139 * defaults to be set, so codec should be provided if it is known.
2141 * @return newly created stream or NULL on error.
2143 AVStream *avformat_new_stream(AVFormatContext *s, const AVCodec *c);
2146 * Wrap an existing array as stream side data.
2149 * @param type side information type
2150 * @param data the side data array. It must be allocated with the av_malloc()
2151 * family of functions. The ownership of the data is transferred to
2153 * @param size side information size
2154 * @return zero on success, a negative AVERROR code on failure. On failure,
2155 * the stream is unchanged and the data remains owned by the caller.
2157 int av_stream_add_side_data(AVStream *st, enum AVPacketSideDataType type,
2158 uint8_t *data, size_t size);
2161 * Allocate new information from stream.
2163 * @param stream stream
2164 * @param type desired side information type
2165 * @param size side information size
2166 * @return pointer to fresh allocated data or NULL otherwise
2168 uint8_t *av_stream_new_side_data(AVStream *stream,
2169 enum AVPacketSideDataType type, int size);
2171 * Get side information from stream.
2173 * @param stream stream
2174 * @param type desired side information type
2175 * @param size pointer for side information size to store (optional)
2176 * @return pointer to data if present or NULL otherwise
2178 uint8_t *av_stream_get_side_data(const AVStream *stream,
2179 enum AVPacketSideDataType type, int *size);
2181 AVProgram *av_new_program(AVFormatContext *s, int id);
2189 * Allocate an AVFormatContext for an output format.
2190 * avformat_free_context() can be used to free the context and
2191 * everything allocated by the framework within it.
2193 * @param *ctx is set to the created format context, or to NULL in
2195 * @param oformat format to use for allocating the context, if NULL
2196 * format_name and filename are used instead
2197 * @param format_name the name of output format to use for allocating the
2198 * context, if NULL filename is used instead
2199 * @param filename the name of the filename to use for allocating the
2200 * context, may be NULL
2201 * @return >= 0 in case of success, a negative AVERROR code in case of
2204 int avformat_alloc_output_context2(AVFormatContext **ctx, AVOutputFormat *oformat,
2205 const char *format_name, const char *filename);
2208 * @addtogroup lavf_decoding
2213 * Find AVInputFormat based on the short name of the input format.
2215 AVInputFormat *av_find_input_format(const char *short_name);
2218 * Guess the file format.
2220 * @param pd data to be probed
2221 * @param is_opened Whether the file is already opened; determines whether
2222 * demuxers with or without AVFMT_NOFILE are probed.
2224 AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
2227 * Guess the file format.
2229 * @param pd data to be probed
2230 * @param is_opened Whether the file is already opened; determines whether
2231 * demuxers with or without AVFMT_NOFILE are probed.
2232 * @param score_max A probe score larger that this is required to accept a
2233 * detection, the variable is set to the actual detection
2235 * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
2236 * to retry with a larger probe buffer.
2238 AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max);
2241 * Guess the file format.
2243 * @param is_opened Whether the file is already opened; determines whether
2244 * demuxers with or without AVFMT_NOFILE are probed.
2245 * @param score_ret The score of the best detection.
2247 AVInputFormat *av_probe_input_format3(AVProbeData *pd, int is_opened, int *score_ret);
2250 * Probe a bytestream to determine the input format. Each time a probe returns
2251 * with a score that is too low, the probe buffer size is increased and another
2252 * attempt is made. When the maximum probe size is reached, the input format
2253 * with the highest score is returned.
2255 * @param pb the bytestream to probe
2256 * @param fmt the input format is put here
2257 * @param url the url of the stream
2258 * @param logctx the log context
2259 * @param offset the offset within the bytestream to probe from
2260 * @param max_probe_size the maximum probe buffer size (zero for default)
2261 * @return the score in case of success, a negative value corresponding to an
2262 * the maximal score is AVPROBE_SCORE_MAX
2263 * AVERROR code otherwise
2265 int av_probe_input_buffer2(AVIOContext *pb, AVInputFormat **fmt,
2266 const char *url, void *logctx,
2267 unsigned int offset, unsigned int max_probe_size);
2270 * Like av_probe_input_buffer2() but returns 0 on success
2272 int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt,
2273 const char *url, void *logctx,
2274 unsigned int offset, unsigned int max_probe_size);
2277 * Open an input stream and read the header. The codecs are not opened.
2278 * The stream must be closed with avformat_close_input().
2280 * @param ps Pointer to user-supplied AVFormatContext (allocated by avformat_alloc_context).
2281 * May be a pointer to NULL, in which case an AVFormatContext is allocated by this
2282 * function and written into ps.
2283 * Note that a user-supplied AVFormatContext will be freed on failure.
2284 * @param url URL of the stream to open.
2285 * @param fmt If non-NULL, this parameter forces a specific input format.
2286 * Otherwise the format is autodetected.
2287 * @param options A dictionary filled with AVFormatContext and demuxer-private options.
2288 * On return this parameter will be destroyed and replaced with a dict containing
2289 * options that were not found. May be NULL.
2291 * @return 0 on success, a negative AVERROR on failure.
2293 * @note If you want to use custom IO, preallocate the format context and set its pb field.
2295 int avformat_open_input(AVFormatContext **ps, const char *url, AVInputFormat *fmt, AVDictionary **options);
2297 attribute_deprecated
2298 int av_demuxer_open(AVFormatContext *ic);
2301 * Read packets of a media file to get stream information. This
2302 * is useful for file formats with no headers such as MPEG. This
2303 * function also computes the real framerate in case of MPEG-2 repeat
2305 * The logical file position is not changed by this function;
2306 * examined packets may be buffered for later processing.
2308 * @param ic media file handle
2309 * @param options If non-NULL, an ic.nb_streams long array of pointers to
2310 * dictionaries, where i-th member contains options for
2311 * codec corresponding to i-th stream.
2312 * On return each dictionary will be filled with options that were not found.
2313 * @return >=0 if OK, AVERROR_xxx on error
2315 * @note this function isn't guaranteed to open all the codecs, so
2316 * options being non-empty at return is a perfectly normal behavior.
2318 * @todo Let the user decide somehow what information is needed so that
2319 * we do not waste time getting stuff the user does not need.
2321 int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options);
2324 * Find the programs which belong to a given stream.
2326 * @param ic media file handle
2327 * @param last the last found program, the search will start after this
2328 * program, or from the beginning if it is NULL
2329 * @param s stream index
2330 * @return the next program which belongs to s, NULL if no program is found or
2331 * the last program is not among the programs of ic.
2333 AVProgram *av_find_program_from_stream(AVFormatContext *ic, AVProgram *last, int s);
2335 void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx);
2338 * Find the "best" stream in the file.
2339 * The best stream is determined according to various heuristics as the most
2340 * likely to be what the user expects.
2341 * If the decoder parameter is non-NULL, av_find_best_stream will find the
2342 * default decoder for the stream's codec; streams for which no decoder can
2343 * be found are ignored.
2345 * @param ic media file handle
2346 * @param type stream type: video, audio, subtitles, etc.
2347 * @param wanted_stream_nb user-requested stream number,
2348 * or -1 for automatic selection
2349 * @param related_stream try to find a stream related (eg. in the same
2350 * program) to this one, or -1 if none
2351 * @param decoder_ret if non-NULL, returns the decoder for the
2353 * @param flags flags; none are currently defined
2354 * @return the non-negative stream number in case of success,
2355 * AVERROR_STREAM_NOT_FOUND if no stream with the requested type
2357 * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
2358 * @note If av_find_best_stream returns successfully and decoder_ret is not
2359 * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
2361 int av_find_best_stream(AVFormatContext *ic,
2362 enum AVMediaType type,
2363 int wanted_stream_nb,
2365 AVCodec **decoder_ret,
2369 * Return the next frame of a stream.
2370 * This function returns what is stored in the file, and does not validate
2371 * that what is there are valid frames for the decoder. It will split what is
2372 * stored in the file into frames and return one for each call. It will not
2373 * omit invalid data between valid frames so as to give the decoder the maximum
2374 * information possible for decoding.
2376 * If pkt->buf is NULL, then the packet is valid until the next
2377 * av_read_frame() or until avformat_close_input(). Otherwise the packet
2378 * is valid indefinitely. In both cases the packet must be freed with
2379 * av_packet_unref when it is no longer needed. For video, the packet contains
2380 * exactly one frame. For audio, it contains an integer number of frames if each
2381 * frame has a known fixed size (e.g. PCM or ADPCM data). If the audio frames
2382 * have a variable size (e.g. MPEG audio), then it contains one frame.
2384 * pkt->pts, pkt->dts and pkt->duration are always set to correct
2385 * values in AVStream.time_base units (and guessed if the format cannot
2386 * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
2387 * has B-frames, so it is better to rely on pkt->dts if you do not
2388 * decompress the payload.
2390 * @return 0 if OK, < 0 on error or end of file
2392 int av_read_frame(AVFormatContext *s, AVPacket *pkt);
2395 * Seek to the keyframe at timestamp.
2396 * 'timestamp' in 'stream_index'.
2398 * @param s media file handle
2399 * @param stream_index If stream_index is (-1), a default
2400 * stream is selected, and timestamp is automatically converted
2401 * from AV_TIME_BASE units to the stream specific time_base.
2402 * @param timestamp Timestamp in AVStream.time_base units
2403 * or, if no stream is specified, in AV_TIME_BASE units.
2404 * @param flags flags which select direction and seeking mode
2405 * @return >= 0 on success
2407 int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
2411 * Seek to timestamp ts.
2412 * Seeking will be done so that the point from which all active streams
2413 * can be presented successfully will be closest to ts and within min/max_ts.
2414 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
2416 * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
2417 * are the file position (this may not be supported by all demuxers).
2418 * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
2419 * in the stream with stream_index (this may not be supported by all demuxers).
2420 * Otherwise all timestamps are in units of the stream selected by stream_index
2421 * or if stream_index is -1, in AV_TIME_BASE units.
2422 * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
2423 * keyframes (this may not be supported by all demuxers).
2424 * If flags contain AVSEEK_FLAG_BACKWARD, it is ignored.
2426 * @param s media file handle
2427 * @param stream_index index of the stream which is used as time base reference
2428 * @param min_ts smallest acceptable timestamp
2429 * @param ts target timestamp
2430 * @param max_ts largest acceptable timestamp
2431 * @param flags flags
2432 * @return >=0 on success, error code otherwise
2434 * @note This is part of the new seek API which is still under construction.
2435 * Thus do not use this yet. It may change at any time, do not expect
2436 * ABI compatibility yet!
2438 int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
2441 * Discard all internally buffered data. This can be useful when dealing with
2442 * discontinuities in the byte stream. Generally works only with formats that
2443 * can resync. This includes headerless formats like MPEG-TS/TS but should also
2444 * work with NUT, Ogg and in a limited way AVI for example.
2446 * The set of streams, the detected duration, stream parameters and codecs do
2447 * not change when calling this function. If you want a complete reset, it's
2448 * better to open a new AVFormatContext.
2450 * This does not flush the AVIOContext (s->pb). If necessary, call
2451 * avio_flush(s->pb) before calling this function.
2453 * @param s media file handle
2454 * @return >=0 on success, error code otherwise
2456 int avformat_flush(AVFormatContext *s);
2459 * Start playing a network-based stream (e.g. RTSP stream) at the
2462 int av_read_play(AVFormatContext *s);
2465 * Pause a network-based stream (e.g. RTSP stream).
2467 * Use av_read_play() to resume it.
2469 int av_read_pause(AVFormatContext *s);
2472 * Close an opened input AVFormatContext. Free it and all its contents
2473 * and set *s to NULL.
2475 void avformat_close_input(AVFormatContext **s);
2480 #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
2481 #define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
2482 #define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
2483 #define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
2486 * @addtogroup lavf_encoding
2490 #define AVSTREAM_INIT_IN_WRITE_HEADER 0 ///< stream parameters initialized in avformat_write_header
2491 #define AVSTREAM_INIT_IN_INIT_OUTPUT 1 ///< stream parameters initialized in avformat_init_output
2494 * Allocate the stream private data and write the stream header to
2495 * an output media file.
2497 * @param s Media file handle, must be allocated with avformat_alloc_context().
2498 * Its oformat field must be set to the desired output format;
2499 * Its pb field must be set to an already opened AVIOContext.
2500 * @param options An AVDictionary filled with AVFormatContext and muxer-private options.
2501 * On return this parameter will be destroyed and replaced with a dict containing
2502 * options that were not found. May be NULL.
2504 * @return AVSTREAM_INIT_IN_WRITE_HEADER on success if the codec had not already been fully initialized in avformat_init,
2505 * AVSTREAM_INIT_IN_INIT_OUTPUT on success if the codec had already been fully initialized in avformat_init,
2506 * negative AVERROR on failure.
2508 * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_init_output.
2510 av_warn_unused_result
2511 int avformat_write_header(AVFormatContext *s, AVDictionary **options);
2514 * Allocate the stream private data and initialize the codec, but do not write the header.
2515 * May optionally be used before avformat_write_header to initialize stream parameters
2516 * before actually writing the header.
2517 * If using this function, do not pass the same options to avformat_write_header.
2519 * @param s Media file handle, must be allocated with avformat_alloc_context().
2520 * Its oformat field must be set to the desired output format;
2521 * Its pb field must be set to an already opened AVIOContext.
2522 * @param options An AVDictionary filled with AVFormatContext and muxer-private options.
2523 * On return this parameter will be destroyed and replaced with a dict containing
2524 * options that were not found. May be NULL.
2526 * @return AVSTREAM_INIT_IN_WRITE_HEADER on success if the codec requires avformat_write_header to fully initialize,
2527 * AVSTREAM_INIT_IN_INIT_OUTPUT on success if the codec has been fully initialized,
2528 * negative AVERROR on failure.
2530 * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_write_header.
2532 av_warn_unused_result
2533 int avformat_init_output(AVFormatContext *s, AVDictionary **options);
2536 * Write a packet to an output media file.
2538 * This function passes the packet directly to the muxer, without any buffering
2539 * or reordering. The caller is responsible for correctly interleaving the
2540 * packets if the format requires it. Callers that want libavformat to handle
2541 * the interleaving should call av_interleaved_write_frame() instead of this
2544 * @param s media file handle
2545 * @param pkt The packet containing the data to be written. Note that unlike
2546 * av_interleaved_write_frame(), this function does not take
2547 * ownership of the packet passed to it (though some muxers may make
2548 * an internal reference to the input packet).
2550 * This parameter can be NULL (at any time, not just at the end), in
2551 * order to immediately flush data buffered within the muxer, for
2552 * muxers that buffer up data internally before writing it to the
2555 * Packet's @ref AVPacket.stream_index "stream_index" field must be
2556 * set to the index of the corresponding stream in @ref
2557 * AVFormatContext.streams "s->streams".
2559 * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2560 * must be set to correct values in the stream's timebase (unless the
2561 * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2562 * they can be set to AV_NOPTS_VALUE).
2563 * The dts for subsequent packets passed to this function must be strictly
2564 * increasing when compared in their respective timebases (unless the
2565 * output format is flagged with the AVFMT_TS_NONSTRICT, then they
2566 * merely have to be nondecreasing). @ref AVPacket.duration
2567 * "duration") should also be set if known.
2568 * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush
2570 * @see av_interleaved_write_frame()
2572 int av_write_frame(AVFormatContext *s, AVPacket *pkt);
2575 * Write a packet to an output media file ensuring correct interleaving.
2577 * This function will buffer the packets internally as needed to make sure the
2578 * packets in the output file are properly interleaved in the order of
2579 * increasing dts. Callers doing their own interleaving should call
2580 * av_write_frame() instead of this function.
2582 * Using this function instead of av_write_frame() can give muxers advance
2583 * knowledge of future packets, improving e.g. the behaviour of the mp4
2584 * muxer for VFR content in fragmenting mode.
2586 * @param s media file handle
2587 * @param pkt The packet containing the data to be written.
2589 * If the packet is reference-counted, this function will take
2590 * ownership of this reference and unreference it later when it sees
2592 * The caller must not access the data through this reference after
2593 * this function returns. If the packet is not reference-counted,
2594 * libavformat will make a copy.
2596 * This parameter can be NULL (at any time, not just at the end), to
2597 * flush the interleaving queues.
2599 * Packet's @ref AVPacket.stream_index "stream_index" field must be
2600 * set to the index of the corresponding stream in @ref
2601 * AVFormatContext.streams "s->streams".
2603 * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
2604 * must be set to correct values in the stream's timebase (unless the
2605 * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
2606 * they can be set to AV_NOPTS_VALUE).
2607 * The dts for subsequent packets in one stream must be strictly
2608 * increasing (unless the output format is flagged with the
2609 * AVFMT_TS_NONSTRICT, then they merely have to be nondecreasing).
2610 * @ref AVPacket.duration "duration") should also be set if known.
2612 * @return 0 on success, a negative AVERROR on error. Libavformat will always
2613 * take care of freeing the packet, even if this function fails.
2615 * @see av_write_frame(), AVFormatContext.max_interleave_delta
2617 int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
2620 * Write an uncoded frame to an output media file.
2622 * The frame must be correctly interleaved according to the container
2623 * specification; if not, then av_interleaved_write_frame() must be used.
2625 * See av_interleaved_write_frame() for details.
2627 int av_write_uncoded_frame(AVFormatContext *s, int stream_index,
2631 * Write an uncoded frame to an output media file.
2633 * If the muxer supports it, this function makes it possible to write an AVFrame
2634 * structure directly, without encoding it into a packet.
2635 * It is mostly useful for devices and similar special muxers that use raw
2636 * video or PCM data and will not serialize it into a byte stream.
2638 * To test whether it is possible to use it with a given muxer and stream,
2639 * use av_write_uncoded_frame_query().
2641 * The caller gives up ownership of the frame and must not access it
2644 * @return >=0 for success, a negative code on error
2646 int av_interleaved_write_uncoded_frame(AVFormatContext *s, int stream_index,
2650 * Test whether a muxer supports uncoded frame.
2652 * @return >=0 if an uncoded frame can be written to that muxer and stream,
2655 int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index);
2658 * Write the stream trailer to an output media file and free the
2659 * file private data.
2661 * May only be called after a successful call to avformat_write_header.
2663 * @param s media file handle
2664 * @return 0 if OK, AVERROR_xxx on error
2666 int av_write_trailer(AVFormatContext *s);
2669 * Return the output format in the list of registered output formats
2670 * which best matches the provided parameters, or return NULL if
2671 * there is no match.
2673 * @param short_name if non-NULL checks if short_name matches with the
2674 * names of the registered formats
2675 * @param filename if non-NULL checks if filename terminates with the
2676 * extensions of the registered formats
2677 * @param mime_type if non-NULL checks if mime_type matches with the
2678 * MIME type of the registered formats
2680 AVOutputFormat *av_guess_format(const char *short_name,
2681 const char *filename,
2682 const char *mime_type);
2685 * Guess the codec ID based upon muxer and filename.
2687 enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
2688 const char *filename, const char *mime_type,
2689 enum AVMediaType type);
2692 * Get timing information for the data currently output.
2693 * The exact meaning of "currently output" depends on the format.
2694 * It is mostly relevant for devices that have an internal buffer and/or
2695 * work in real time.
2696 * @param s media file handle
2697 * @param stream stream in the media file
2698 * @param[out] dts DTS of the last packet output for the stream, in stream
2700 * @param[out] wall absolute time when that packet whas output,
2702 * @return 0 if OK, AVERROR(ENOSYS) if the format does not support it
2703 * Note: some formats or devices may not allow to measure dts and wall
2706 int av_get_output_timestamp(struct AVFormatContext *s, int stream,
2707 int64_t *dts, int64_t *wall);
2716 * @defgroup lavf_misc Utility functions
2720 * Miscellaneous utility functions related to both muxing and demuxing
2725 * Send a nice hexadecimal dump of a buffer to the specified file stream.
2727 * @param f The file stream pointer where the dump should be sent to.
2729 * @param size buffer size
2731 * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2
2733 void av_hex_dump(FILE *f, const uint8_t *buf, int size);
2736 * Send a nice hexadecimal dump of a buffer to the log.
2738 * @param avcl A pointer to an arbitrary struct of which the first field is a
2739 * pointer to an AVClass struct.
2740 * @param level The importance level of the message, lower values signifying
2741 * higher importance.
2743 * @param size buffer size
2745 * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2
2747 void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size);
2750 * Send a nice dump of a packet to the specified file stream.
2752 * @param f The file stream pointer where the dump should be sent to.
2753 * @param pkt packet to dump
2754 * @param dump_payload True if the payload must be displayed, too.
2755 * @param st AVStream that the packet belongs to
2757 void av_pkt_dump2(FILE *f, const AVPacket *pkt, int dump_payload, const AVStream *st);
2761 * Send a nice dump of a packet to the log.
2763 * @param avcl A pointer to an arbitrary struct of which the first field is a
2764 * pointer to an AVClass struct.
2765 * @param level The importance level of the message, lower values signifying
2766 * higher importance.
2767 * @param pkt packet to dump
2768 * @param dump_payload True if the payload must be displayed, too.
2769 * @param st AVStream that the packet belongs to
2771 void av_pkt_dump_log2(void *avcl, int level, const AVPacket *pkt, int dump_payload,
2772 const AVStream *st);
2775 * Get the AVCodecID for the given codec tag tag.
2776 * If no codec id is found returns AV_CODEC_ID_NONE.
2778 * @param tags list of supported codec_id-codec_tag pairs, as stored
2779 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2780 * @param tag codec tag to match to a codec ID
2782 enum AVCodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
2785 * Get the codec tag for the given codec id id.
2786 * If no codec tag is found returns 0.
2788 * @param tags list of supported codec_id-codec_tag pairs, as stored
2789 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2790 * @param id codec ID to match to a codec tag
2792 unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id);
2795 * Get the codec tag for the given codec id.
2797 * @param tags list of supported codec_id - codec_tag pairs, as stored
2798 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
2799 * @param id codec id that should be searched for in the list
2800 * @param tag A pointer to the found tag
2801 * @return 0 if id was not found in tags, > 0 if it was found
2803 int av_codec_get_tag2(const struct AVCodecTag * const *tags, enum AVCodecID id,
2806 int av_find_default_stream_index(AVFormatContext *s);
2809 * Get the index for a specific timestamp.
2811 * @param st stream that the timestamp belongs to
2812 * @param timestamp timestamp to retrieve the index for
2813 * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
2814 * to the timestamp which is <= the requested one, if backward
2815 * is 0, then it will be >=
2816 * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
2817 * @return < 0 if no such timestamp could be found
2819 int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
2822 * Add an index entry into a sorted list. Update the entry if the list
2823 * already contains it.
2825 * @param timestamp timestamp in the time base of the given stream
2827 int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
2828 int size, int distance, int flags);
2832 * Split a URL string into components.
2834 * The pointers to buffers for storing individual components may be null,
2835 * in order to ignore that component. Buffers for components not found are
2836 * set to empty strings. If the port is not found, it is set to a negative
2839 * @param proto the buffer for the protocol
2840 * @param proto_size the size of the proto buffer
2841 * @param authorization the buffer for the authorization
2842 * @param authorization_size the size of the authorization buffer
2843 * @param hostname the buffer for the host name
2844 * @param hostname_size the size of the hostname buffer
2845 * @param port_ptr a pointer to store the port number in
2846 * @param path the buffer for the path
2847 * @param path_size the size of the path buffer
2848 * @param url the URL to split
2850 void av_url_split(char *proto, int proto_size,
2851 char *authorization, int authorization_size,
2852 char *hostname, int hostname_size,
2854 char *path, int path_size,
2859 * Print detailed information about the input or output format, such as
2860 * duration, bitrate, streams, container, programs, metadata, side data,
2861 * codec and time base.
2863 * @param ic the context to analyze
2864 * @param index index of the stream to dump information about
2865 * @param url the URL to print, such as source or destination file
2866 * @param is_output Select whether the specified context is an input(0) or output(1)
2868 void av_dump_format(AVFormatContext *ic,
2874 #define AV_FRAME_FILENAME_FLAGS_MULTIPLE 1 ///< Allow multiple %d
2877 * Return in 'buf' the path with '%d' replaced by a number.
2879 * Also handles the '%0nd' format where 'n' is the total number
2880 * of digits and '%%'.
2882 * @param buf destination buffer
2883 * @param buf_size destination buffer size
2884 * @param path numbered sequence string
2885 * @param number frame number
2886 * @param flags AV_FRAME_FILENAME_FLAGS_*
2887 * @return 0 if OK, -1 on format error
2889 int av_get_frame_filename2(char *buf, int buf_size,
2890 const char *path, int number, int flags);
2892 int av_get_frame_filename(char *buf, int buf_size,
2893 const char *path, int number);
2896 * Check whether filename actually is a numbered sequence generator.
2898 * @param filename possible numbered sequence string
2899 * @return 1 if a valid numbered sequence string, 0 otherwise
2901 int av_filename_number_test(const char *filename);
2904 * Generate an SDP for an RTP session.
2906 * Note, this overwrites the id values of AVStreams in the muxer contexts
2907 * for getting unique dynamic payload types.
2909 * @param ac array of AVFormatContexts describing the RTP streams. If the
2910 * array is composed by only one context, such context can contain
2911 * multiple AVStreams (one AVStream per RTP stream). Otherwise,
2912 * all the contexts in the array (an AVCodecContext per RTP stream)
2913 * must contain only one AVStream.
2914 * @param n_files number of AVCodecContexts contained in ac
2915 * @param buf buffer where the SDP will be stored (must be allocated by
2917 * @param size the size of the buffer
2918 * @return 0 if OK, AVERROR_xxx on error
2920 int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size);
2923 * Return a positive value if the given filename has one of the given
2924 * extensions, 0 otherwise.
2926 * @param filename file name to check against the given extensions
2927 * @param extensions a comma-separated list of filename extensions
2929 int av_match_ext(const char *filename, const char *extensions);
2932 * Test if the given container can store a codec.
2934 * @param ofmt container to check for compatibility
2935 * @param codec_id codec to potentially store in container
2936 * @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
2938 * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
2939 * A negative number if this information is not available.
2941 int avformat_query_codec(const AVOutputFormat *ofmt, enum AVCodecID codec_id,
2942 int std_compliance);
2945 * @defgroup riff_fourcc RIFF FourCCs
2947 * Get the tables mapping RIFF FourCCs to libavcodec AVCodecIDs. The tables are
2948 * meant to be passed to av_codec_get_id()/av_codec_get_tag() as in the
2951 * uint32_t tag = MKTAG('H', '2', '6', '4');
2952 * const struct AVCodecTag *table[] = { avformat_get_riff_video_tags(), 0 };
2953 * enum AVCodecID id = av_codec_get_id(table, tag);
2957 * @return the table mapping RIFF FourCCs for video to libavcodec AVCodecID.
2959 const struct AVCodecTag *avformat_get_riff_video_tags(void);
2961 * @return the table mapping RIFF FourCCs for audio to AVCodecID.
2963 const struct AVCodecTag *avformat_get_riff_audio_tags(void);
2965 * @return the table mapping MOV FourCCs for video to libavcodec AVCodecID.
2967 const struct AVCodecTag *avformat_get_mov_video_tags(void);
2969 * @return the table mapping MOV FourCCs for audio to AVCodecID.
2971 const struct AVCodecTag *avformat_get_mov_audio_tags(void);
2978 * Guess the sample aspect ratio of a frame, based on both the stream and the
2979 * frame aspect ratio.
2981 * Since the frame aspect ratio is set by the codec but the stream aspect ratio
2982 * is set by the demuxer, these two may not be equal. This function tries to
2983 * return the value that you should use if you would like to display the frame.
2985 * Basic logic is to use the stream aspect ratio if it is set to something sane
2986 * otherwise use the frame aspect ratio. This way a container setting, which is
2987 * usually easy to modify can override the coded value in the frames.
2989 * @param format the format context which the stream is part of
2990 * @param stream the stream which the frame is part of
2991 * @param frame the frame with the aspect ratio to be determined
2992 * @return the guessed (valid) sample_aspect_ratio, 0/1 if no idea
2994 AVRational av_guess_sample_aspect_ratio(AVFormatContext *format, AVStream *stream, AVFrame *frame);
2997 * Guess the frame rate, based on both the container and codec information.
2999 * @param ctx the format context which the stream is part of
3000 * @param stream the stream which the frame is part of
3001 * @param frame the frame for which the frame rate should be determined, may be NULL
3002 * @return the guessed (valid) frame rate, 0/1 if no idea
3004 AVRational av_guess_frame_rate(AVFormatContext *ctx, AVStream *stream, AVFrame *frame);
3007 * Check if the stream st contained in s is matched by the stream specifier
3010 * See the "stream specifiers" chapter in the documentation for the syntax
3013 * @return >0 if st is matched by spec;
3014 * 0 if st is not matched by spec;
3015 * AVERROR code if spec is invalid
3017 * @note A stream specifier can match several streams in the format.
3019 int avformat_match_stream_specifier(AVFormatContext *s, AVStream *st,
3022 int avformat_queue_attached_pictures(AVFormatContext *s);
3026 * Apply a list of bitstream filters to a packet.
3028 * @param codec AVCodecContext, usually from an AVStream
3029 * @param pkt the packet to apply filters to. If, on success, the returned
3030 * packet has size == 0 and side_data_elems == 0, it indicates that
3031 * the packet should be dropped
3032 * @param bsfc a NULL-terminated list of filters to apply
3033 * @return >=0 on success;
3034 * AVERROR code on failure
3036 attribute_deprecated
3037 int av_apply_bitstream_filters(AVCodecContext *codec, AVPacket *pkt,
3038 AVBitStreamFilterContext *bsfc);
3041 enum AVTimebaseSource {
3042 AVFMT_TBCF_AUTO = -1,
3045 #if FF_API_R_FRAME_RATE
3046 AVFMT_TBCF_R_FRAMERATE,
3051 * Transfer internal timing information from one stream to another.
3053 * This function is useful when doing stream copy.
3055 * @param ofmt target output format for ost
3056 * @param ost output stream which needs timings copy and adjustments
3057 * @param ist reference input stream to copy timings from
3058 * @param copy_tb define from where the stream codec timebase needs to be imported
3060 int avformat_transfer_internal_stream_timing_info(const AVOutputFormat *ofmt,
3061 AVStream *ost, const AVStream *ist,
3062 enum AVTimebaseSource copy_tb);
3065 * Get the internal codec timebase from a stream.
3067 * @param st input stream to extract the timebase from
3069 AVRational av_stream_get_codec_timebase(const AVStream *st);
3075 #endif /* AVFORMAT_AVFORMAT_H */