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 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 Libav 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 * @defgroup lavf_decoding Demuxing
71 * Demuxers read a media file and split it into chunks of data (@em packets). A
72 * @ref AVPacket "packet" contains one or more frames which belong a single
73 * elementary stream. In lavf API this process is represented by the
74 * avformat_open_input() function for opening a file, av_read_frame() for
75 * reading a single packet and finally avformat_close_input(), which does the
78 * @section lavf_decoding_open Opening a media file
79 * The minimum information required to open a file is its URL or filename, which
80 * is passed to avformat_open_input(), as in the following code:
82 * const char *url = "in.mp3";
83 * AVFormatContext *s = NULL;
84 * int ret = avformat_open_input(&s, url, NULL, NULL);
88 * The above code attempts to allocate an AVFormatContext, open the
89 * specified file (autodetecting the format) and read the header, exporting the
90 * information stored there into s. Some formats do not have a header or do not
91 * store enough information there, so it is recommended that you call the
92 * avformat_find_stream_info() function which tries to read and decode a few
93 * frames to find missing information.
95 * In some cases you might want to preallocate an AVFormatContext yourself with
96 * avformat_alloc_context() and do some tweaking on it before passing it to
97 * avformat_open_input(). One such case is when you want to use custom functions
98 * for reading input data instead of lavf internal I/O layer.
99 * To do that, create your own AVIOContext with avio_alloc_context(), passing
100 * your reading callbacks to it. Then set the @em pb field of your
101 * AVFormatContext to newly created AVIOContext.
103 * After you have finished reading the file, you must close it with
104 * avformat_close_input(). It will free everything associated with the file.
106 * @section lavf_decoding_read Reading from an opened file
108 * @section lavf_decoding_seek Seeking
111 * @defgroup lavf_encoding Muxing
115 * @defgroup lavf_io I/O Read/Write
119 * @defgroup lavf_codec Demuxers
121 * @defgroup lavf_codec_native Native Demuxers
124 * @defgroup lavf_codec_wrappers External library wrappers
128 * @defgroup lavf_protos I/O Protocols
131 * @defgroup lavf_internal Internal
139 #include <stdio.h> /* FILE */
140 #include "libavcodec/avcodec.h"
141 #include "libavutil/dict.h"
142 #include "libavutil/log.h"
145 #include "libavformat/version.h"
147 struct AVFormatContext;
151 * @defgroup metadata_api Public Metadata API
154 * The metadata API allows libavformat to export metadata tags to a client
155 * application when demuxing. Conversely it allows a client application to
156 * set metadata when muxing.
158 * Metadata is exported or set as pairs of key/value strings in the 'metadata'
159 * fields of the AVFormatContext, AVStream, AVChapter and AVProgram structs
160 * using the @ref lavu_dict "AVDictionary" API. Like all strings in FFmpeg,
161 * metadata is assumed to be UTF-8 encoded Unicode. Note that metadata
162 * exported by demuxers isn't checked to be valid UTF-8 in most cases.
164 * Important concepts to keep in mind:
165 * - Keys are unique; there can never be 2 tags with the same key. This is
166 * also meant semantically, i.e., a demuxer should not knowingly produce
167 * several keys that are literally different but semantically identical.
168 * E.g., key=Author5, key=Author6. In this example, all authors must be
169 * placed in the same tag.
170 * - Metadata is flat, not hierarchical; there are no subtags. If you
171 * want to store, e.g., the email address of the child of producer Alice
172 * and actor Bob, that could have key=alice_and_bobs_childs_email_address.
173 * - Several modifiers can be applied to the tag name. This is done by
174 * appending a dash character ('-') and the modifier name in the order
175 * they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng.
176 * - language -- a tag whose value is localized for a particular language
177 * is appended with the ISO 639-2/B 3-letter language code.
178 * For example: Author-ger=Michael, Author-eng=Mike
179 * The original/default language is in the unqualified "Author" tag.
180 * A demuxer should set a default if it sets any translated tag.
181 * - sorting -- a modified version of a tag that should be used for
182 * sorting will have '-sort' appended. E.g. artist="The Beatles",
183 * artist-sort="Beatles, The".
185 * - Demuxers attempt to export metadata in a generic format, however tags
186 * with no generic equivalents are left as they are stored in the container.
187 * Follows a list of generic tag names:
190 album -- name of the set this work belongs to
191 album_artist -- main creator of the set/album, if different from artist.
192 e.g. "Various Artists" for compilation albums.
193 artist -- main creator of the work
194 comment -- any additional description of the file.
195 composer -- who composed the work, if different from artist.
196 copyright -- name of copyright holder.
197 creation_time-- date when the file was created, preferably in ISO 8601.
198 date -- date when the work was created, preferably in ISO 8601.
199 disc -- number of a subset, e.g. disc in a multi-disc collection.
200 encoder -- name/settings of the software/hardware that produced the file.
201 encoded_by -- person/group who created the file.
202 filename -- original name of the file.
203 genre -- <self-evident>.
204 language -- main language in which the work is performed, preferably
205 in ISO 639-2 format. Multiple languages can be specified by
206 separating them with commas.
207 performer -- artist who performed the work, if different from artist.
208 E.g for "Also sprach Zarathustra", artist would be "Richard
209 Strauss" and performer "London Philharmonic Orchestra".
210 publisher -- name of the label/publisher.
211 service_name -- name of the service in broadcasting (channel name).
212 service_provider -- name of the service provider in broadcasting.
213 title -- name of the work.
214 track -- number of this work in the set, can be in form current/total.
215 variant_bitrate -- the total bitrate of the bitrate variant that the current stream is part of
218 * Look in the examples section for an application example how to use the Metadata API.
223 /* packet functions */
227 * Allocate and read the payload of a packet and initialize its
228 * fields with default values.
231 * @param size desired payload size
232 * @return >0 (read size) if OK, AVERROR_xxx otherwise
234 int av_get_packet(AVIOContext *s, AVPacket *pkt, int size);
238 * Read data and append it to the current content of the AVPacket.
239 * If pkt->size is 0 this is identical to av_get_packet.
240 * Note that this uses av_grow_packet and thus involves a realloc
241 * which is inefficient. Thus this function should only be used
242 * when there is no reasonable way to know (an upper bound of)
246 * @param size amount of data to read
247 * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data
248 * will not be lost even if an error occurs.
250 int av_append_packet(AVIOContext *s, AVPacket *pkt, int size);
252 /*************************************************/
253 /* fractional numbers for exact pts handling */
256 * The exact value of the fractional number is: 'val + num / den'.
257 * num is assumed to be 0 <= num < den.
259 typedef struct AVFrac {
260 int64_t val, num, den;
263 /*************************************************/
264 /* input/output formats */
269 * This structure contains the data a format has to probe a file.
271 typedef struct AVProbeData {
272 const char *filename;
273 unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
274 int buf_size; /**< Size of buf except extra allocated bytes */
277 #define AVPROBE_SCORE_MAX 100 ///< maximum score, half of that is used for file-extension-based detection
278 #define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
280 /// Demuxer will use avio_open, no opened file should be provided by the caller.
281 #define AVFMT_NOFILE 0x0001
282 #define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
283 #define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
284 #define AVFMT_RAWPICTURE 0x0020 /**< Format wants AVPicture structure for
286 #define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
287 #define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
288 #define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
289 #define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */
290 #define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */
291 #define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */
292 #define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */
293 #define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fallback to binary search via read_timestamp */
294 #define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fallback to generic search */
295 #define AVFMT_NO_BYTE_SEEK 0x8000 /**< Format does not allow seeking by bytes */
296 #define AVFMT_ALLOW_FLUSH 0x10000 /**< Format allows flushing. If not set, the muxer will not receive a NULL packet in the write_packet function. */
297 #define AVFMT_TS_NONSTRICT 0x8000000 /**< Format does not require strictly
298 increasing timestamps, but they must
299 still be monotonic */
302 * @addtogroup lavf_encoding
305 typedef struct AVOutputFormat {
308 * Descriptive name for the format, meant to be more human-readable
309 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
312 const char *long_name;
313 const char *mime_type;
314 const char *extensions; /**< comma-separated filename extensions */
316 * size of private data so that it can be allocated in the wrapper
320 enum CodecID audio_codec; /**< default audio codec */
321 enum CodecID video_codec; /**< default video codec */
322 int (*write_header)(struct AVFormatContext *);
324 * Write a packet. If AVFMT_ALLOW_FLUSH is set in flags,
325 * pkt can be NULL in order to flush data buffered in the muxer.
326 * When flushing, return 0 if there still is more data to flush,
327 * or 1 if everything was flushed and there is no more buffered
330 int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
331 int (*write_trailer)(struct AVFormatContext *);
333 * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_RAWPICTURE,
334 * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
335 * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH
338 int (*interleave_packet)(struct AVFormatContext *, AVPacket *out,
339 AVPacket *in, int flush);
342 * List of supported codec_id-codec_tag pairs, ordered by "better
343 * choice first". The arrays are all terminated by CODEC_ID_NONE.
345 const struct AVCodecTag * const *codec_tag;
347 enum CodecID subtitle_codec; /**< default subtitle codec */
349 const AVClass *priv_class; ///< AVClass for the private context
352 * Test if the given codec can be stored in this container.
354 * @return 1 if the codec is supported, 0 if it is not.
355 * A negative number if unknown.
357 int (*query_codec)(enum CodecID id, int std_compliance);
359 void (*get_output_timestamp)(struct AVFormatContext *s, int stream,
360 int64_t *dts, int64_t *wall);
363 struct AVOutputFormat *next;
370 * @addtogroup lavf_decoding
373 typedef struct AVInputFormat {
375 * A comma separated list of short names for the format. New names
376 * may be appended with a minor bump.
381 * Descriptive name for the format, meant to be more human-readable
382 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
385 const char *long_name;
388 * Size of private data so that it can be allocated in the wrapper.
393 * Tell if a given file has a chance of being parsed as this format.
394 * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
395 * big so you do not have to check for that unless you need more.
397 int (*read_probe)(AVProbeData *);
400 * Read the format header and initialize the AVFormatContext
401 * structure. Return 0 if OK. 'ap' if non-NULL contains
402 * additional parameters. Only used in raw format right
403 * now. 'av_new_stream' should be called to create new streams.
405 int (*read_header)(struct AVFormatContext *);
408 * Read one packet and put it in 'pkt'. pts and flags are also
409 * set. 'av_new_stream' can be called only if the flag
410 * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
411 * background thread).
412 * @return 0 on success, < 0 on error.
413 * When returning an error, pkt must not have been allocated
414 * or must be freed before returning
416 int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
419 * Close the stream. The AVFormatContext and AVStreams are not
420 * freed by this function
422 int (*read_close)(struct AVFormatContext *);
425 * Seek to a given timestamp relative to the frames in
426 * stream component stream_index.
427 * @param stream_index Must not be -1.
428 * @param flags Selects which direction should be preferred if no exact
429 * match is available.
430 * @return >= 0 on success (but not necessarily the new offset)
432 int (*read_seek)(struct AVFormatContext *,
433 int stream_index, int64_t timestamp, int flags);
436 * Get the next timestamp in stream[stream_index].time_base units.
437 * @return the timestamp or AV_NOPTS_VALUE if an error occurred
439 int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
440 int64_t *pos, int64_t pos_limit);
443 * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
444 * AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
445 * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK.
450 * If extensions are defined, then no probe is done. You should
451 * usually not use extension format guessing because it is not
454 const char *extensions;
457 * General purpose read-only value that the format can use.
462 * Start/resume playing - only meaningful if using a network-based format
465 int (*read_play)(struct AVFormatContext *);
468 * Pause playing - only meaningful if using a network-based format
471 int (*read_pause)(struct AVFormatContext *);
473 const struct AVCodecTag * const *codec_tag;
476 * Seek to timestamp ts.
477 * Seeking will be done so that the point from which all active streams
478 * can be presented successfully will be closest to ts and within min/max_ts.
479 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
481 int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
483 const AVClass *priv_class; ///< AVClass for the private context
486 struct AVInputFormat *next;
492 enum AVStreamParseType {
494 AVSTREAM_PARSE_FULL, /**< full parsing and repack */
495 AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
496 AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
497 AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
500 typedef struct AVIndexEntry {
502 int64_t timestamp; /**<
503 * Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are available
504 * when seeking to this entry. That means preferable PTS on keyframe based formats.
505 * But demuxers can choose to store a different timestamp, if it is more convenient for the implementation or nothing better
508 #define AVINDEX_KEYFRAME 0x0001
510 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).
511 int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
514 #define AV_DISPOSITION_DEFAULT 0x0001
515 #define AV_DISPOSITION_DUB 0x0002
516 #define AV_DISPOSITION_ORIGINAL 0x0004
517 #define AV_DISPOSITION_COMMENT 0x0008
518 #define AV_DISPOSITION_LYRICS 0x0010
519 #define AV_DISPOSITION_KARAOKE 0x0020
522 * Track should be used during playback by default.
523 * Useful for subtitle track that should be displayed
524 * even when user did not explicitly ask for subtitles.
526 #define AV_DISPOSITION_FORCED 0x0040
527 #define AV_DISPOSITION_HEARING_IMPAIRED 0x0080 /**< stream for hearing impaired audiences */
528 #define AV_DISPOSITION_VISUAL_IMPAIRED 0x0100 /**< stream for visual impaired audiences */
529 #define AV_DISPOSITION_CLEAN_EFFECTS 0x0200 /**< stream without voice */
533 * New fields can be added to the end with minor version bumps.
534 * Removal, reordering and changes to existing fields require a major
536 * sizeof(AVStream) must not be used outside libav*.
538 typedef struct AVStream {
539 int index; /**< stream index in AVFormatContext */
540 int id; /**< format-specific stream ID */
541 AVCodecContext *codec; /**< codec context */
543 * Real base framerate of the stream.
544 * This is the lowest framerate with which all timestamps can be
545 * represented accurately (it is the least common multiple of all
546 * framerates in the stream). Note, this value is just a guess!
547 * For example, if the time base is 1/90000 and all frames have either
548 * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
550 AVRational r_frame_rate;
554 * encoding: pts generation when outputting stream
559 * This is the fundamental unit of time (in seconds) in terms
560 * of which frame timestamps are represented. For fixed-fps content,
561 * time base should be 1/framerate and timestamp increments should be 1.
562 * decoding: set by libavformat
563 * encoding: set by libavformat in av_write_header
565 AVRational time_base;
566 enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
569 * Decoding: pts of the first frame of the stream in presentation order, in stream time base.
570 * Only set this if you are absolutely 100% sure that the value you set
571 * it to really is the pts of the first frame.
572 * This may be undefined (AV_NOPTS_VALUE).
573 * @note The ASF header does NOT contain a correct start_time the ASF
574 * demuxer must NOT set this.
579 * Decoding: duration of the stream, in stream time base.
580 * If a source file does not specify a duration, but does specify
581 * a bitrate, this value will be estimated from bitrate and file size.
585 int64_t nb_frames; ///< number of frames in this stream if known or 0
587 int disposition; /**< AV_DISPOSITION_* bit field */
590 * sample aspect ratio (0 if unknown)
591 * - encoding: Set by user.
592 * - decoding: Set by libavformat.
594 AVRational sample_aspect_ratio;
596 AVDictionary *metadata;
601 AVRational avg_frame_rate;
603 /*****************************************************************
604 * All fields below this line are not part of the public API. They
605 * may not be used outside of libavformat and can be changed and
607 * New public fields should be added right above.
608 *****************************************************************
612 * Number of frames that have been demuxed during av_find_stream_info()
614 int codec_info_nb_frames;
618 * This is the MPEG-TS stream identifier +1
621 int stream_identifier;
623 int64_t interleaver_chunk_size;
624 int64_t interleaver_chunk_duration;
627 * Stream information used internally by av_find_stream_info()
629 #define MAX_STD_TIMEBASES (60*12+5)
632 int64_t duration_gcd;
634 double duration_error[2][2][MAX_STD_TIMEBASES];
635 int64_t codec_info_duration;
636 int nb_decoded_frames;
638 const uint8_t *cur_ptr;
642 // Timestamp generation support:
644 * Timestamp corresponding to the last dts sync point.
646 * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
647 * a DTS is received from the underlying container. Otherwise set to
648 * AV_NOPTS_VALUE by default.
650 int64_t reference_dts;
653 int last_IP_duration;
657 * Number of packets to buffer for codec probing
659 #define MAX_PROBE_PACKETS 2500
663 * last packet in packet_buffer for this stream when muxing.
665 struct AVPacketList *last_in_packet_buffer;
666 AVProbeData probe_data;
667 #define MAX_REORDER_DELAY 16
668 int64_t pts_buffer[MAX_REORDER_DELAY+1];
669 /* av_read_frame() support */
670 enum AVStreamParseType need_parsing;
671 struct AVCodecParserContext *parser;
673 AVIndexEntry *index_entries; /**< Only used if the format does not
674 support seeking natively. */
675 int nb_index_entries;
676 unsigned int index_entries_allocated_size;
678 int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
681 * flag to indicate that probing is requested
682 * NOT PART OF PUBLIC API
687 #define AV_PROGRAM_RUNNING 1
690 * New fields can be added to the end with minor version bumps.
691 * Removal, reordering and changes to existing fields require a major
693 * sizeof(AVProgram) must not be used outside libav*.
695 typedef struct AVProgram {
698 enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
699 unsigned int *stream_index;
700 unsigned int nb_stream_indexes;
701 AVDictionary *metadata;
708 #define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
709 (streams are added dynamically) */
711 typedef struct AVChapter {
712 int id; ///< unique ID to identify the chapter
713 AVRational time_base; ///< time base in which the start/end timestamps are specified
714 int64_t start, end; ///< chapter start/end time in time_base units
715 AVDictionary *metadata;
719 * Format I/O context.
720 * New fields can be added to the end with minor version bumps.
721 * Removal, reordering and changes to existing fields require a major
723 * sizeof(AVFormatContext) must not be used outside libav*, use
724 * avformat_alloc_context() to create an AVFormatContext.
726 typedef struct AVFormatContext {
728 * A class for logging and AVOptions. Set by avformat_alloc_context().
729 * Exports (de)muxer private options if they exist.
731 const AVClass *av_class;
734 * Can only be iformat or oformat, not both at the same time.
736 * decoding: set by avformat_open_input().
737 * encoding: set by the user.
739 struct AVInputFormat *iformat;
740 struct AVOutputFormat *oformat;
743 * Format private data. This is an AVOptions-enabled struct
744 * if and only if iformat/oformat.priv_class is not NULL.
751 * decoding: either set by the user before avformat_open_input() (then
752 * the user must close it manually) or set by avformat_open_input().
753 * encoding: set by the user.
755 * Do NOT set this field if AVFMT_NOFILE flag is set in
756 * iformat/oformat.flags. In such a case, the (de)muxer will handle
757 * I/O in some other way and this field will be NULL.
762 * A list of all streams in the file. New streams are created with
763 * avformat_new_stream().
765 * decoding: streams are created by libavformat in avformat_open_input().
766 * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
767 * appear in av_read_frame().
768 * encoding: streams are created by the user before avformat_write_header().
770 unsigned int nb_streams;
773 char filename[1024]; /**< input or output filename */
775 int ctx_flags; /**< Format-specific flags, see AVFMTCTX_xx */
778 * Decoding: position of the first frame of the component, in
779 * AV_TIME_BASE fractional seconds. NEVER set this value directly:
780 * It is deduced from the AVStream values.
785 * Decoding: duration of the stream, in AV_TIME_BASE fractional
786 * seconds. Only set this value if you know none of the individual stream
787 * durations and also do not set any of them. This is deduced from the
788 * AVStream values if not set.
793 * Decoding: total stream bitrate in bit/s, 0 if not
794 * available. Never set it directly if the file_size and the
795 * duration are known as FFmpeg can compute it automatically.
799 unsigned int packet_size;
803 #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
804 #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
805 #define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
806 #define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
807 #define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
808 #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
809 #define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
810 #define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted
811 #define AVFMT_FLAG_MP4A_LATM 0x8000 ///< Enable RTP MP4A-LATM payload
812 #define AVFMT_FLAG_SORT_DTS 0x10000 ///< try to interleave outputted packets by dts (using this flag can slow demuxing down)
813 #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)
814 #define AVFMT_FLAG_KEEP_SIDE_DATA 0x40000 ///< Dont merge side data but keep it seperate.
817 * decoding: size of data to probe; encoding: unused.
819 unsigned int probesize;
822 * decoding: maximum time (in AV_TIME_BASE units) during which the input should
823 * be analyzed in avformat_find_stream_info().
825 int max_analyze_duration;
830 unsigned int nb_programs;
831 AVProgram **programs;
834 * Forced video codec_id.
835 * Demuxing: Set by user.
837 enum CodecID video_codec_id;
840 * Forced audio codec_id.
841 * Demuxing: Set by user.
843 enum CodecID audio_codec_id;
846 * Forced subtitle codec_id.
847 * Demuxing: Set by user.
849 enum CodecID subtitle_codec_id;
852 * Maximum amount of memory in bytes to use for the index of each stream.
853 * If the index exceeds this size, entries will be discarded as
854 * needed to maintain a smaller size. This can lead to slower or less
855 * accurate seeking (depends on demuxer).
856 * Demuxers for which a full in-memory index is mandatory will ignore
859 * demuxing: set by user
861 unsigned int max_index_size;
864 * Maximum amount of memory in bytes to use for buffering frames
865 * obtained from realtime capture devices.
867 unsigned int max_picture_buffer;
869 unsigned int nb_chapters;
870 AVChapter **chapters;
873 * Flags to enable debugging.
876 #define FF_FDEBUG_TS 0x0001
878 AVDictionary *metadata;
881 * Start time of the stream in real world time, in microseconds
882 * since the unix epoch (00:00 1st January 1970). That is, pts=0
883 * in the stream was captured at this real world time.
884 * - encoding: Set by user.
885 * - decoding: Unused.
887 int64_t start_time_realtime;
890 * decoding: number of frames used to probe fps
895 * Error recognition; higher values will detect more errors but may
896 * misdetect some more or less valid parts as errors.
898 * - decoding: Set by user.
900 int error_recognition;
903 * Custom interrupt callbacks for the I/O layer.
905 * decoding: set by the user before avformat_open_input().
906 * encoding: set by the user before avformat_write_header()
907 * (mainly useful for AVFMT_NOFILE formats). The callback
908 * should also be passed to avio_open2() if it's used to
911 AVIOInterruptCB interrupt_callback;
914 * Transport stream id.
915 * This will be moved into demuxer private options. Thus no API/ABI compatibility
920 * Audio preload in microseconds.
921 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
922 * - encoding: Set by user via AVOptions (NO direct access)
928 * Max chunk time in microseconds.
929 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
930 * - encoding: Set by user via AVOptions (NO direct access)
933 int max_chunk_duration;
936 * Max chunk size in bytes
937 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
938 * - encoding: Set by user via AVOptions (NO direct access)
943 /*****************************************************************
944 * All fields below this line are not part of the public API. They
945 * may not be used outside of libavformat and can be changed and
947 * New public fields should be added right above.
948 *****************************************************************
951 * Raw packets from the demuxer, prior to parsing and decoding.
952 * This buffer is used for buffering packets until the codec can
953 * be identified, as parsing cannot be done without knowing the
956 struct AVPacketList *raw_packet_buffer;
957 struct AVPacketList *raw_packet_buffer_end;
959 * Remaining size available for raw_packet_buffer, in bytes.
961 #define RAW_PACKET_BUFFER_SIZE 2500000
962 int raw_packet_buffer_remaining_size;
965 * This buffer is only needed when packets were already buffered but
966 * not decoded, for example to get the codec parameters in MPEG
969 struct AVPacketList *packet_buffer;
970 struct AVPacketList *packet_buffer_end;
972 /* av_read_frame() support */
975 /* av_seek_frame() support */
976 int64_t data_offset; /**< offset of the first packet */
979 typedef struct AVPacketList {
981 struct AVPacketList *next;
986 * @defgroup lavf_core Core functions
989 * Functions for querying libavformat capabilities, allocating core structures,
995 * Return the LIBAVFORMAT_VERSION_INT constant.
997 unsigned avformat_version(void);
1000 * Return the libavformat build-time configuration.
1002 const char *avformat_configuration(void);
1005 * Return the libavformat license.
1007 const char *avformat_license(void);
1010 * Initialize libavformat and register all the muxers, demuxers and
1011 * protocols. If you do not call this function, then you can select
1012 * exactly which formats you want to support.
1014 * @see av_register_input_format()
1015 * @see av_register_output_format()
1016 * @see av_register_protocol()
1018 void av_register_all(void);
1020 void av_register_input_format(AVInputFormat *format);
1021 void av_register_output_format(AVOutputFormat *format);
1024 * Do global initialization of network components. This is optional,
1025 * but recommended, since it avoids the overhead of implicitly
1026 * doing the setup for each session.
1028 * Calling this function will become mandatory if using network
1029 * protocols at some major version bump.
1031 int avformat_network_init(void);
1034 * Undo the initialization done by avformat_network_init.
1036 int avformat_network_deinit(void);
1039 * If f is NULL, returns the first registered input format,
1040 * if f is non-NULL, returns the next registered input format after f
1041 * or NULL if f is the last one.
1043 AVInputFormat *av_iformat_next(AVInputFormat *f);
1046 * If f is NULL, returns the first registered output format,
1047 * if f is non-NULL, returns the next registered output format after f
1048 * or NULL if f is the last one.
1050 AVOutputFormat *av_oformat_next(AVOutputFormat *f);
1053 * Allocate an AVFormatContext.
1054 * avformat_free_context() can be used to free the context and everything
1055 * allocated by the framework within it.
1057 AVFormatContext *avformat_alloc_context(void);
1060 * Free an AVFormatContext and all its streams.
1061 * @param s context to free
1063 void avformat_free_context(AVFormatContext *s);
1066 * Get the AVClass for AVFormatContext. It can be used in combination with
1067 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
1069 * @see av_opt_find().
1071 const AVClass *avformat_get_class(void);
1074 * Add a new stream to a media file.
1076 * When demuxing, it is called by the demuxer in read_header(). If the
1077 * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
1078 * be called in read_packet().
1080 * When muxing, should be called by the user before avformat_write_header().
1082 * @param c If non-NULL, the AVCodecContext corresponding to the new stream
1083 * will be initialized to use this codec. This is needed for e.g. codec-specific
1084 * defaults to be set, so codec should be provided if it is known.
1086 * @return newly created stream or NULL on error.
1088 AVStream *avformat_new_stream(AVFormatContext *s, AVCodec *c);
1090 AVProgram *av_new_program(AVFormatContext *s, int id);
1098 attribute_deprecated void av_pkt_dump(FILE *f, AVPacket *pkt, int dump_payload);
1099 attribute_deprecated void av_pkt_dump_log(void *avcl, int level, AVPacket *pkt,
1103 #if FF_API_ALLOC_OUTPUT_CONTEXT
1105 * @deprecated deprecated in favor of avformat_alloc_output_context2()
1107 attribute_deprecated
1108 AVFormatContext *avformat_alloc_output_context(const char *format,
1109 AVOutputFormat *oformat,
1110 const char *filename);
1114 * Allocate an AVFormatContext for an output format.
1115 * avformat_free_context() can be used to free the context and
1116 * everything allocated by the framework within it.
1118 * @param *ctx is set to the created format context, or to NULL in
1120 * @param oformat format to use for allocating the context, if NULL
1121 * format_name and filename are used instead
1122 * @param format_name the name of output format to use for allocating the
1123 * context, if NULL filename is used instead
1124 * @param filename the name of the filename to use for allocating the
1125 * context, may be NULL
1126 * @return >= 0 in case of success, a negative AVERROR code in case of
1129 int avformat_alloc_output_context2(AVFormatContext **ctx, AVOutputFormat *oformat,
1130 const char *format_name, const char *filename);
1133 * @addtogroup lavf_decoding
1138 * Find AVInputFormat based on the short name of the input format.
1140 AVInputFormat *av_find_input_format(const char *short_name);
1143 * Guess the file format.
1145 * @param is_opened Whether the file is already opened; determines whether
1146 * demuxers with or without AVFMT_NOFILE are probed.
1148 AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
1151 * Guess the file format.
1153 * @param is_opened Whether the file is already opened; determines whether
1154 * demuxers with or without AVFMT_NOFILE are probed.
1155 * @param score_max A probe score larger that this is required to accept a
1156 * detection, the variable is set to the actual detection
1158 * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
1159 * to retry with a larger probe buffer.
1161 AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max);
1164 * Guess the file format.
1166 * @param is_opened Whether the file is already opened; determines whether
1167 * demuxers with or without AVFMT_NOFILE are probed.
1168 * @param score_ret The score of the best detection.
1170 AVInputFormat *av_probe_input_format3(AVProbeData *pd, int is_opened, int *score_ret);
1173 * Probe a bytestream to determine the input format. Each time a probe returns
1174 * with a score that is too low, the probe buffer size is increased and another
1175 * attempt is made. When the maximum probe size is reached, the input format
1176 * with the highest score is returned.
1178 * @param pb the bytestream to probe
1179 * @param fmt the input format is put here
1180 * @param filename the filename of the stream
1181 * @param logctx the log context
1182 * @param offset the offset within the bytestream to probe from
1183 * @param max_probe_size the maximum probe buffer size (zero for default)
1184 * @return 0 in case of success, a negative value corresponding to an
1185 * AVERROR code otherwise
1187 int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt,
1188 const char *filename, void *logctx,
1189 unsigned int offset, unsigned int max_probe_size);
1192 * Open an input stream and read the header. The codecs are not opened.
1193 * The stream must be closed with av_close_input_file().
1195 * @param ps Pointer to user-supplied AVFormatContext (allocated by avformat_alloc_context).
1196 * May be a pointer to NULL, in which case an AVFormatContext is allocated by this
1197 * function and written into ps.
1198 * Note that a user-supplied AVFormatContext will be freed on failure.
1199 * @param filename Name of the stream to open.
1200 * @param fmt If non-NULL, this parameter forces a specific input format.
1201 * Otherwise the format is autodetected.
1202 * @param options A dictionary filled with AVFormatContext and demuxer-private options.
1203 * On return this parameter will be destroyed and replaced with a dict containing
1204 * options that were not found. May be NULL.
1206 * @return 0 on success, a negative AVERROR on failure.
1208 * @note If you want to use custom IO, preallocate the format context and set its pb field.
1210 int avformat_open_input(AVFormatContext **ps, const char *filename, AVInputFormat *fmt, AVDictionary **options);
1212 attribute_deprecated
1213 int av_demuxer_open(AVFormatContext *ic);
1215 #if FF_API_FORMAT_PARAMETERS
1217 * Read packets of a media file to get stream information. This
1218 * is useful for file formats with no headers such as MPEG. This
1219 * function also computes the real framerate in case of MPEG-2 repeat
1221 * The logical file position is not changed by this function;
1222 * examined packets may be buffered for later processing.
1224 * @param ic media file handle
1225 * @return >=0 if OK, AVERROR_xxx on error
1226 * @todo Let the user decide somehow what information is needed so that
1227 * we do not waste time getting stuff the user does not need.
1229 * @deprecated use avformat_find_stream_info.
1231 attribute_deprecated
1232 int av_find_stream_info(AVFormatContext *ic);
1236 * Read packets of a media file to get stream information. This
1237 * is useful for file formats with no headers such as MPEG. This
1238 * function also computes the real framerate in case of MPEG-2 repeat
1240 * The logical file position is not changed by this function;
1241 * examined packets may be buffered for later processing.
1243 * @param ic media file handle
1244 * @param options If non-NULL, an ic.nb_streams long array of pointers to
1245 * dictionaries, where i-th member contains options for
1246 * codec corresponding to i-th stream.
1247 * On return each dictionary will be filled with options that were not found.
1248 * @return >=0 if OK, AVERROR_xxx on error
1250 * @note this function isn't guaranteed to open all the codecs, so
1251 * options being non-empty at return is a perfectly normal behavior.
1253 * @todo Let the user decide somehow what information is needed so that
1254 * we do not waste time getting stuff the user does not need.
1256 int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options);
1259 * Find the programs which belong to a given stream.
1261 * @param ic media file handle
1262 * @param last the last found program, the search will start after this
1263 * program, or from the beginning if it is NULL
1264 * @param s stream index
1265 * @return the next program which belongs to s, NULL if no program is found or
1266 * the last program is not among the programs of ic.
1268 AVProgram *av_find_program_from_stream(AVFormatContext *ic, AVProgram *last, int s);
1271 * Find the "best" stream in the file.
1272 * The best stream is determined according to various heuristics as the most
1273 * likely to be what the user expects.
1274 * If the decoder parameter is non-NULL, av_find_best_stream will find the
1275 * default decoder for the stream's codec; streams for which no decoder can
1276 * be found are ignored.
1278 * @param ic media file handle
1279 * @param type stream type: video, audio, subtitles, etc.
1280 * @param wanted_stream_nb user-requested stream number,
1281 * or -1 for automatic selection
1282 * @param related_stream try to find a stream related (eg. in the same
1283 * program) to this one, or -1 if none
1284 * @param decoder_ret if non-NULL, returns the decoder for the
1286 * @param flags flags; none are currently defined
1287 * @return the non-negative stream number in case of success,
1288 * AVERROR_STREAM_NOT_FOUND if no stream with the requested type
1290 * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
1291 * @note If av_find_best_stream returns successfully and decoder_ret is not
1292 * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
1294 int av_find_best_stream(AVFormatContext *ic,
1295 enum AVMediaType type,
1296 int wanted_stream_nb,
1298 AVCodec **decoder_ret,
1302 * Read a transport packet from a media file.
1304 * This function is obsolete and should never be used.
1305 * Use av_read_frame() instead.
1307 * @param s media file handle
1308 * @param pkt is filled
1309 * @return 0 if OK, AVERROR_xxx on error
1311 int av_read_packet(AVFormatContext *s, AVPacket *pkt);
1314 * Return the next frame of a stream.
1315 * This function returns what is stored in the file, and does not validate
1316 * that what is there are valid frames for the decoder. It will split what is
1317 * stored in the file into frames and return one for each call. It will not
1318 * omit invalid data between valid frames so as to give the decoder the maximum
1319 * information possible for decoding.
1321 * The returned packet is valid
1322 * until the next av_read_frame() or until av_close_input_file() and
1323 * must be freed with av_free_packet. For video, the packet contains
1324 * exactly one frame. For audio, it contains an integer number of
1325 * frames if each frame has a known fixed size (e.g. PCM or ADPCM
1326 * data). If the audio frames have a variable size (e.g. MPEG audio),
1327 * then it contains one frame.
1329 * pkt->pts, pkt->dts and pkt->duration are always set to correct
1330 * values in AVStream.time_base units (and guessed if the format cannot
1331 * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
1332 * has B-frames, so it is better to rely on pkt->dts if you do not
1333 * decompress the payload.
1335 * @return 0 if OK, < 0 on error or end of file
1337 int av_read_frame(AVFormatContext *s, AVPacket *pkt);
1340 * Seek to the keyframe at timestamp.
1341 * 'timestamp' in 'stream_index'.
1342 * @param stream_index If stream_index is (-1), a default
1343 * stream is selected, and timestamp is automatically converted
1344 * from AV_TIME_BASE units to the stream specific time_base.
1345 * @param timestamp Timestamp in AVStream.time_base units
1346 * or, if no stream is specified, in AV_TIME_BASE units.
1347 * @param flags flags which select direction and seeking mode
1348 * @return >= 0 on success
1350 int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
1354 * Seek to timestamp ts.
1355 * Seeking will be done so that the point from which all active streams
1356 * can be presented successfully will be closest to ts and within min/max_ts.
1357 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
1359 * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
1360 * are the file position (this may not be supported by all demuxers).
1361 * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
1362 * in the stream with stream_index (this may not be supported by all demuxers).
1363 * Otherwise all timestamps are in units of the stream selected by stream_index
1364 * or if stream_index is -1, in AV_TIME_BASE units.
1365 * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
1366 * keyframes (this may not be supported by all demuxers).
1368 * @param stream_index index of the stream which is used as time base reference
1369 * @param min_ts smallest acceptable timestamp
1370 * @param ts target timestamp
1371 * @param max_ts largest acceptable timestamp
1372 * @param flags flags
1373 * @return >=0 on success, error code otherwise
1375 * @note This is part of the new seek API which is still under construction.
1376 * Thus do not use this yet. It may change at any time, do not expect
1377 * ABI compatibility yet!
1379 int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
1382 * Start playing a network-based stream (e.g. RTSP stream) at the
1385 int av_read_play(AVFormatContext *s);
1388 * Pause a network-based stream (e.g. RTSP stream).
1390 * Use av_read_play() to resume it.
1392 int av_read_pause(AVFormatContext *s);
1394 #if FF_API_CLOSE_INPUT_FILE
1396 * @deprecated use avformat_close_input()
1397 * Close a media file (but not its codecs).
1399 * @param s media file handle
1401 attribute_deprecated
1402 void av_close_input_file(AVFormatContext *s);
1406 * Close an opened input AVFormatContext. Free it and all its contents
1407 * and set *s to NULL.
1409 void avformat_close_input(AVFormatContext **s);
1414 #if FF_API_NEW_STREAM
1416 * Add a new stream to a media file.
1418 * Can only be called in the read_header() function. If the flag
1419 * AVFMTCTX_NOHEADER is in the format context, then new streams
1420 * can be added in read_packet too.
1422 * @param s media file handle
1423 * @param id file-format-dependent stream ID
1425 attribute_deprecated
1426 AVStream *av_new_stream(AVFormatContext *s, int id);
1429 #if FF_API_SET_PTS_INFO
1431 * @deprecated this function is not supposed to be called outside of lavf
1433 attribute_deprecated
1434 void av_set_pts_info(AVStream *s, int pts_wrap_bits,
1435 unsigned int pts_num, unsigned int pts_den);
1438 #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
1439 #define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
1440 #define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
1441 #define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
1444 * @addtogroup lavf_encoding
1448 * Allocate the stream private data and write the stream header to
1449 * an output media file.
1451 * @param s Media file handle, must be allocated with avformat_alloc_context().
1452 * Its oformat field must be set to the desired output format;
1453 * Its pb field must be set to an already openened AVIOContext.
1454 * @param options An AVDictionary filled with AVFormatContext and muxer-private options.
1455 * On return this parameter will be destroyed and replaced with a dict containing
1456 * options that were not found. May be NULL.
1458 * @return 0 on success, negative AVERROR on failure.
1460 * @see av_opt_find, av_dict_set, avio_open, av_oformat_next.
1462 int avformat_write_header(AVFormatContext *s, AVDictionary **options);
1465 * Write a packet to an output media file.
1467 * The packet shall contain one audio or video frame.
1468 * The packet must be correctly interleaved according to the container
1469 * specification, if not then av_interleaved_write_frame must be used.
1471 * @param s media file handle
1472 * @param pkt The packet, which contains the stream_index, buf/buf_size,
1474 * This can be NULL (at any time, not just at the end), in
1475 * order to immediately flush data buffered within the muxer,
1476 * for muxers that buffer up data internally before writing it
1478 * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush
1480 int av_write_frame(AVFormatContext *s, AVPacket *pkt);
1483 * Write a packet to an output media file ensuring correct interleaving.
1485 * The packet must contain one audio or video frame.
1486 * If the packets are already correctly interleaved, the application should
1487 * call av_write_frame() instead as it is slightly faster. It is also important
1488 * to keep in mind that completely non-interleaved input will need huge amounts
1489 * of memory to interleave with this, so it is preferable to interleave at the
1492 * @param s media file handle
1493 * @param pkt The packet containing the data to be written. Libavformat takes
1494 * ownership of the data and will free it when it sees fit using the packet's
1495 * @ref AVPacket.destruct "destruct" field. The caller must not access the data
1496 * after this function returns, as it may already be freed.
1497 * Packet's @ref AVPacket.stream_index "stream_index" field must be set to the
1498 * index of the corresponding stream in @ref AVFormatContext.streams
1500 * It is very strongly recommended that timing information (@ref AVPacket.pts
1501 * "pts", @ref AVPacket.dts "dts" @ref AVPacket.duration "duration") is set to
1504 * @return 0 on success, a negative AVERROR on error.
1506 int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
1509 * Interleave a packet per dts in an output media file.
1511 * Packets with pkt->destruct == av_destruct_packet will be freed inside this
1512 * function, so they cannot be used after it. Note that calling av_free_packet()
1513 * on them is still safe.
1515 * @param s media file handle
1516 * @param out the interleaved packet will be output here
1517 * @param pkt the input packet
1518 * @param flush 1 if no further packets are available as input and all
1519 * remaining packets should be output
1520 * @return 1 if a packet was output, 0 if no packet could be output,
1521 * < 0 if an error occurred
1523 int av_interleave_packet_per_dts(AVFormatContext *s, AVPacket *out,
1524 AVPacket *pkt, int flush);
1527 * Write the stream trailer to an output media file and free the
1528 * file private data.
1530 * May only be called after a successful call to av_write_header.
1532 * @param s media file handle
1533 * @return 0 if OK, AVERROR_xxx on error
1535 int av_write_trailer(AVFormatContext *s);
1538 * Return the output format in the list of registered output formats
1539 * which best matches the provided parameters, or return NULL if
1540 * there is no match.
1542 * @param short_name if non-NULL checks if short_name matches with the
1543 * names of the registered formats
1544 * @param filename if non-NULL checks if filename terminates with the
1545 * extensions of the registered formats
1546 * @param mime_type if non-NULL checks if mime_type matches with the
1547 * MIME type of the registered formats
1549 AVOutputFormat *av_guess_format(const char *short_name,
1550 const char *filename,
1551 const char *mime_type);
1554 * Guess the codec ID based upon muxer and filename.
1556 enum CodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
1557 const char *filename, const char *mime_type,
1558 enum AVMediaType type);
1561 * Get timing information for the data currently output.
1562 * The exact meaning of "currently output" depends on the format.
1563 * It is mostly relevant for devices that have an internal buffer and/or
1564 * work in real time.
1565 * @param s media file handle
1566 * @param stream stream in the media file
1567 * @param dts[out] DTS of the last packet output for the stream, in stream
1569 * @param wall[out] absolute time when that packet whas output,
1571 * @return 0 if OK, AVERROR(ENOSYS) if the format does not support it
1572 * Note: some formats or devices may not allow to measure dts and wall
1575 int av_get_output_timestamp(struct AVFormatContext *s, int stream,
1576 int64_t *dts, int64_t *wall);
1585 * @defgroup lavf_misc Utility functions
1589 * Miscelaneous utility functions related to both muxing and demuxing
1594 * Send a nice hexadecimal dump of a buffer to the specified file stream.
1596 * @param f The file stream pointer where the dump should be sent to.
1598 * @param size buffer size
1600 * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2
1602 void av_hex_dump(FILE *f, uint8_t *buf, int size);
1605 * Send a nice hexadecimal dump of a buffer to the log.
1607 * @param avcl A pointer to an arbitrary struct of which the first field is a
1608 * pointer to an AVClass struct.
1609 * @param level The importance level of the message, lower values signifying
1610 * higher importance.
1612 * @param size buffer size
1614 * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2
1616 void av_hex_dump_log(void *avcl, int level, uint8_t *buf, int size);
1619 * Send a nice dump of a packet to the specified file stream.
1621 * @param f The file stream pointer where the dump should be sent to.
1622 * @param pkt packet to dump
1623 * @param dump_payload True if the payload must be displayed, too.
1624 * @param st AVStream that the packet belongs to
1626 void av_pkt_dump2(FILE *f, AVPacket *pkt, int dump_payload, AVStream *st);
1630 * Send a nice dump of a packet to the log.
1632 * @param avcl A pointer to an arbitrary struct of which the first field is a
1633 * pointer to an AVClass struct.
1634 * @param level The importance level of the message, lower values signifying
1635 * higher importance.
1636 * @param pkt packet to dump
1637 * @param dump_payload True if the payload must be displayed, too.
1638 * @param st AVStream that the packet belongs to
1640 void av_pkt_dump_log2(void *avcl, int level, AVPacket *pkt, int dump_payload,
1644 * Get the CodecID for the given codec tag tag.
1645 * If no codec id is found returns CODEC_ID_NONE.
1647 * @param tags list of supported codec_id-codec_tag pairs, as stored
1648 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
1650 enum CodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
1653 * Get the codec tag for the given codec id id.
1654 * If no codec tag is found returns 0.
1656 * @param tags list of supported codec_id-codec_tag pairs, as stored
1657 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
1659 unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum CodecID id);
1661 int av_find_default_stream_index(AVFormatContext *s);
1664 * Get the index for a specific timestamp.
1665 * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
1666 * to the timestamp which is <= the requested one, if backward
1667 * is 0, then it will be >=
1668 * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
1669 * @return < 0 if no such timestamp could be found
1671 int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
1674 * Add an index entry into a sorted list. Update the entry if the list
1675 * already contains it.
1677 * @param timestamp timestamp in the time base of the given stream
1679 int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
1680 int size, int distance, int flags);
1684 * Split a URL string into components.
1686 * The pointers to buffers for storing individual components may be null,
1687 * in order to ignore that component. Buffers for components not found are
1688 * set to empty strings. If the port is not found, it is set to a negative
1691 * @param proto the buffer for the protocol
1692 * @param proto_size the size of the proto buffer
1693 * @param authorization the buffer for the authorization
1694 * @param authorization_size the size of the authorization buffer
1695 * @param hostname the buffer for the host name
1696 * @param hostname_size the size of the hostname buffer
1697 * @param port_ptr a pointer to store the port number in
1698 * @param path the buffer for the path
1699 * @param path_size the size of the path buffer
1700 * @param url the URL to split
1702 void av_url_split(char *proto, int proto_size,
1703 char *authorization, int authorization_size,
1704 char *hostname, int hostname_size,
1706 char *path, int path_size,
1710 void av_dump_format(AVFormatContext *ic,
1716 * Get the current time in microseconds.
1718 int64_t av_gettime(void);
1721 * Return in 'buf' the path with '%d' replaced by a number.
1723 * Also handles the '%0nd' format where 'n' is the total number
1724 * of digits and '%%'.
1726 * @param buf destination buffer
1727 * @param buf_size destination buffer size
1728 * @param path numbered sequence string
1729 * @param number frame number
1730 * @return 0 if OK, -1 on format error
1732 int av_get_frame_filename(char *buf, int buf_size,
1733 const char *path, int number);
1736 * Check whether filename actually is a numbered sequence generator.
1738 * @param filename possible numbered sequence string
1739 * @return 1 if a valid numbered sequence string, 0 otherwise
1741 int av_filename_number_test(const char *filename);
1744 * Generate an SDP for an RTP session.
1746 * @param ac array of AVFormatContexts describing the RTP streams. If the
1747 * array is composed by only one context, such context can contain
1748 * multiple AVStreams (one AVStream per RTP stream). Otherwise,
1749 * all the contexts in the array (an AVCodecContext per RTP stream)
1750 * must contain only one AVStream.
1751 * @param n_files number of AVCodecContexts contained in ac
1752 * @param buf buffer where the SDP will be stored (must be allocated by
1754 * @param size the size of the buffer
1755 * @return 0 if OK, AVERROR_xxx on error
1757 int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size);
1760 * Return a positive value if the given filename has one of the given
1761 * extensions, 0 otherwise.
1763 * @param extensions a comma-separated list of filename extensions
1765 int av_match_ext(const char *filename, const char *extensions);
1768 * Test if the given container can store a codec.
1770 * @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
1772 * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
1773 * A negative number if this information is not available.
1775 int avformat_query_codec(AVOutputFormat *ofmt, enum CodecID codec_id, int std_compliance);
1781 #endif /* AVFORMAT_AVFORMAT_H */