2 * copyright (c) 2001 Fabrice Bellard
4 * This file is part of Libav.
6 * Libav 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 * Libav 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 Libav; 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 Libav,
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 #if FF_API_OLD_METADATA2
225 * @defgroup old_metadata Old metadata API
226 * The following functions are deprecated, use
227 * their equivalents from libavutil/dict.h instead.
231 #define AV_METADATA_MATCH_CASE AV_DICT_MATCH_CASE
232 #define AV_METADATA_IGNORE_SUFFIX AV_DICT_IGNORE_SUFFIX
233 #define AV_METADATA_DONT_STRDUP_KEY AV_DICT_DONT_STRDUP_KEY
234 #define AV_METADATA_DONT_STRDUP_VAL AV_DICT_DONT_STRDUP_VAL
235 #define AV_METADATA_DONT_OVERWRITE AV_DICT_DONT_OVERWRITE
237 typedef attribute_deprecated AVDictionary AVMetadata;
238 typedef attribute_deprecated AVDictionaryEntry AVMetadataTag;
240 typedef struct AVMetadataConv AVMetadataConv;
243 * Get a metadata element with matching key.
245 * @param prev Set to the previous matching element to find the next.
246 * If set to NULL the first matching element is returned.
247 * @param flags Allows case as well as suffix-insensitive comparisons.
248 * @return Found tag or NULL, changing key or value leads to undefined behavior.
250 attribute_deprecated AVDictionaryEntry *
251 av_metadata_get(AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags);
254 * Set the given tag in *pm, overwriting an existing tag.
256 * @param pm pointer to a pointer to a metadata struct. If *pm is NULL
257 * a metadata struct is allocated and put in *pm.
258 * @param key tag key to add to *pm (will be av_strduped depending on flags)
259 * @param value tag value to add to *pm (will be av_strduped depending on flags).
260 * Passing a NULL value will cause an existing tag to be deleted.
261 * @return >= 0 on success otherwise an error code <0
263 attribute_deprecated int av_metadata_set2(AVDictionary **pm, const char *key, const char *value, int flags);
266 * This function is provided for compatibility reason and currently does nothing.
268 attribute_deprecated void av_metadata_conv(struct AVFormatContext *ctx, const AVMetadataConv *d_conv,
269 const AVMetadataConv *s_conv);
272 * Copy metadata from one AVDictionary struct into another.
273 * @param dst pointer to a pointer to a AVDictionary struct. If *dst is NULL,
274 * this function will allocate a struct for you and put it in *dst
275 * @param src pointer to source AVDictionary struct
276 * @param flags flags to use when setting metadata in *dst
277 * @note metadata is read using the AV_DICT_IGNORE_SUFFIX flag
279 attribute_deprecated void av_metadata_copy(AVDictionary **dst, AVDictionary *src, int flags);
282 * Free all the memory allocated for an AVDictionary struct.
284 attribute_deprecated void av_metadata_free(AVDictionary **m);
291 /* packet functions */
295 * Allocate and read the payload of a packet and initialize its
296 * fields with default values.
299 * @param size desired payload size
300 * @return >0 (read size) if OK, AVERROR_xxx otherwise
302 int av_get_packet(AVIOContext *s, AVPacket *pkt, int size);
306 * Read data and append it to the current content of the AVPacket.
307 * If pkt->size is 0 this is identical to av_get_packet.
308 * Note that this uses av_grow_packet and thus involves a realloc
309 * which is inefficient. Thus this function should only be used
310 * when there is no reasonable way to know (an upper bound of)
314 * @param size amount of data to read
315 * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data
316 * will not be lost even if an error occurs.
318 int av_append_packet(AVIOContext *s, AVPacket *pkt, int size);
320 /*************************************************/
321 /* fractional numbers for exact pts handling */
324 * The exact value of the fractional number is: 'val + num / den'.
325 * num is assumed to be 0 <= num < den.
327 typedef struct AVFrac {
328 int64_t val, num, den;
331 /*************************************************/
332 /* input/output formats */
337 * This structure contains the data a format has to probe a file.
339 typedef struct AVProbeData {
340 const char *filename;
341 unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
342 int buf_size; /**< Size of buf except extra allocated bytes */
345 #define AVPROBE_SCORE_MAX 100 ///< maximum score, half of that is used for file-extension-based detection
346 #define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
348 typedef struct AVFormatParameters {
349 #if FF_API_FORMAT_PARAMETERS
350 attribute_deprecated AVRational time_base;
351 attribute_deprecated int sample_rate;
352 attribute_deprecated int channels;
353 attribute_deprecated int width;
354 attribute_deprecated int height;
355 attribute_deprecated enum PixelFormat pix_fmt;
356 attribute_deprecated int channel; /**< Used to select DV channel. */
357 attribute_deprecated const char *standard; /**< deprecated, use demuxer-specific options instead. */
358 attribute_deprecated unsigned int mpeg2ts_raw:1; /**< deprecated, use mpegtsraw demuxer */
359 /**< deprecated, use mpegtsraw demuxer-specific options instead */
360 attribute_deprecated unsigned int mpeg2ts_compute_pcr:1;
361 attribute_deprecated unsigned int initial_pause:1; /**< Do not begin to play the stream
362 immediately (RTSP only). */
363 attribute_deprecated unsigned int prealloced_context:1;
365 } AVFormatParameters;
367 /// Demuxer will use avio_open, no opened file should be provided by the caller.
368 #define AVFMT_NOFILE 0x0001
369 #define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
370 #define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
371 #define AVFMT_RAWPICTURE 0x0020 /**< Format wants AVPicture structure for
373 #define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
374 #define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
375 #define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
376 #define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */
377 #define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */
378 #define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */
379 #define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */
380 #define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fallback to binary search via read_timestamp */
381 #define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fallback to generic search */
382 #define AVFMT_NO_BYTE_SEEK 0x8000 /**< Format does not allow seeking by bytes */
385 * @addtogroup lavf_encoding
388 typedef struct AVOutputFormat {
391 * Descriptive name for the format, meant to be more human-readable
392 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
395 const char *long_name;
396 const char *mime_type;
397 const char *extensions; /**< comma-separated filename extensions */
399 * size of private data so that it can be allocated in the wrapper
403 enum CodecID audio_codec; /**< default audio codec */
404 enum CodecID video_codec; /**< default video codec */
405 int (*write_header)(struct AVFormatContext *);
406 int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
407 int (*write_trailer)(struct AVFormatContext *);
409 * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_RAWPICTURE,
410 * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
411 * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS
415 * Currently only used to set pixel format if not YUV420P.
417 int (*set_parameters)(struct AVFormatContext *, AVFormatParameters *);
418 int (*interleave_packet)(struct AVFormatContext *, AVPacket *out,
419 AVPacket *in, int flush);
422 * List of supported codec_id-codec_tag pairs, ordered by "better
423 * choice first". The arrays are all terminated by CODEC_ID_NONE.
425 const struct AVCodecTag * const *codec_tag;
427 enum CodecID subtitle_codec; /**< default subtitle codec */
429 #if FF_API_OLD_METADATA2
430 const AVMetadataConv *metadata_conv;
433 const AVClass *priv_class; ///< AVClass for the private context
436 * Test if the given codec can be stored in this container.
438 * @return 1 if the codec is supported, 0 if it is not.
439 * A negative number if unknown.
441 int (*query_codec)(enum CodecID id, int std_compliance);
444 struct AVOutputFormat *next;
451 * @addtogroup lavf_decoding
454 typedef struct AVInputFormat {
456 * A comma separated list of short names for the format. New names
457 * may be appended with a minor bump.
462 * Descriptive name for the format, meant to be more human-readable
463 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
466 const char *long_name;
469 * Size of private data so that it can be allocated in the wrapper.
474 * Tell if a given file has a chance of being parsed as this format.
475 * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
476 * big so you do not have to check for that unless you need more.
478 int (*read_probe)(AVProbeData *);
481 * Read the format header and initialize the AVFormatContext
482 * structure. Return 0 if OK. 'ap' if non-NULL contains
483 * additional parameters. Only used in raw format right
484 * now. 'av_new_stream' should be called to create new streams.
486 int (*read_header)(struct AVFormatContext *,
487 AVFormatParameters *ap);
490 * Read one packet and put it in 'pkt'. pts and flags are also
491 * set. 'av_new_stream' can be called only if the flag
492 * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
493 * background thread).
494 * @return 0 on success, < 0 on error.
495 * When returning an error, pkt must not have been allocated
496 * or must be freed before returning
498 int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
501 * Close the stream. The AVFormatContext and AVStreams are not
502 * freed by this function
504 int (*read_close)(struct AVFormatContext *);
507 * Seek to a given timestamp relative to the frames in
508 * stream component stream_index.
509 * @param stream_index Must not be -1.
510 * @param flags Selects which direction should be preferred if no exact
511 * match is available.
512 * @return >= 0 on success (but not necessarily the new offset)
514 int (*read_seek)(struct AVFormatContext *,
515 int stream_index, int64_t timestamp, int flags);
518 * Get the next timestamp in stream[stream_index].time_base units.
519 * @return the timestamp or AV_NOPTS_VALUE if an error occurred
521 int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
522 int64_t *pos, int64_t pos_limit);
525 * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
526 * AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
527 * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK.
532 * If extensions are defined, then no probe is done. You should
533 * usually not use extension format guessing because it is not
536 const char *extensions;
539 * General purpose read-only value that the format can use.
544 * Start/resume playing - only meaningful if using a network-based format
547 int (*read_play)(struct AVFormatContext *);
550 * Pause playing - only meaningful if using a network-based format
553 int (*read_pause)(struct AVFormatContext *);
555 const struct AVCodecTag * const *codec_tag;
558 * Seek to timestamp ts.
559 * Seeking will be done so that the point from which all active streams
560 * can be presented successfully will be closest to ts and within min/max_ts.
561 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
563 int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
565 #if FF_API_OLD_METADATA2
566 const AVMetadataConv *metadata_conv;
569 const AVClass *priv_class; ///< AVClass for the private context
572 struct AVInputFormat *next;
578 enum AVStreamParseType {
580 AVSTREAM_PARSE_FULL, /**< full parsing and repack */
581 AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
582 AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
583 AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
586 typedef struct AVIndexEntry {
589 #define AVINDEX_KEYFRAME 0x0001
591 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).
592 int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
595 #define AV_DISPOSITION_DEFAULT 0x0001
596 #define AV_DISPOSITION_DUB 0x0002
597 #define AV_DISPOSITION_ORIGINAL 0x0004
598 #define AV_DISPOSITION_COMMENT 0x0008
599 #define AV_DISPOSITION_LYRICS 0x0010
600 #define AV_DISPOSITION_KARAOKE 0x0020
603 * Track should be used during playback by default.
604 * Useful for subtitle track that should be displayed
605 * even when user did not explicitly ask for subtitles.
607 #define AV_DISPOSITION_FORCED 0x0040
608 #define AV_DISPOSITION_HEARING_IMPAIRED 0x0080 /**< stream for hearing impaired audiences */
609 #define AV_DISPOSITION_VISUAL_IMPAIRED 0x0100 /**< stream for visual impaired audiences */
610 #define AV_DISPOSITION_CLEAN_EFFECTS 0x0200 /**< stream without voice */
614 * New fields can be added to the end with minor version bumps.
615 * Removal, reordering and changes to existing fields require a major
617 * sizeof(AVStream) must not be used outside libav*.
619 typedef struct AVStream {
620 int index; /**< stream index in AVFormatContext */
621 int id; /**< format-specific stream ID */
622 AVCodecContext *codec; /**< codec context */
624 * Real base framerate of the stream.
625 * This is the lowest framerate with which all timestamps can be
626 * represented accurately (it is the least common multiple of all
627 * framerates in the stream). Note, this value is just a guess!
628 * For example, if the time base is 1/90000 and all frames have either
629 * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
631 AVRational r_frame_rate;
634 #if FF_API_REORDER_PRIVATE
635 /* internal data used in av_find_stream_info() */
640 * encoding: pts generation when outputting stream
645 * This is the fundamental unit of time (in seconds) in terms
646 * of which frame timestamps are represented. For fixed-fps content,
647 * time base should be 1/framerate and timestamp increments should be 1.
648 * decoding: set by libavformat
649 * encoding: set by libavformat in av_write_header
651 AVRational time_base;
652 #if FF_API_REORDER_PRIVATE
653 int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
655 #if FF_API_STREAM_COPY
656 /* ffmpeg.c private use */
657 attribute_deprecated int stream_copy; /**< If set, just copy stream. */
659 enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
661 #if FF_API_AVSTREAM_QUALITY
662 //FIXME move stuff to a flags field?
664 * Quality, as it has been removed from AVCodecContext and put in AVVideoFrame.
665 * MN: dunno if that is the right place for it
667 attribute_deprecated float quality;
671 * Decoding: pts of the first frame of the stream, in stream time base.
672 * Only set this if you are absolutely 100% sure that the value you set
673 * it to really is the pts of the first frame.
674 * This may be undefined (AV_NOPTS_VALUE).
679 * Decoding: duration of the stream, in stream time base.
680 * If a source file does not specify a duration, but does specify
681 * a bitrate, this value will be estimated from bitrate and file size.
685 #if FF_API_REORDER_PRIVATE
686 /* av_read_frame() support */
687 enum AVStreamParseType need_parsing;
688 struct AVCodecParserContext *parser;
691 int last_IP_duration;
693 /* av_seek_frame() support */
694 AVIndexEntry *index_entries; /**< Only used if the format does not
695 support seeking natively. */
696 int nb_index_entries;
697 unsigned int index_entries_allocated_size;
700 int64_t nb_frames; ///< number of frames in this stream if known or 0
702 int disposition; /**< AV_DISPOSITION_* bit field */
704 #if FF_API_REORDER_PRIVATE
705 AVProbeData probe_data;
706 #define MAX_REORDER_DELAY 16
707 int64_t pts_buffer[MAX_REORDER_DELAY+1];
711 * sample aspect ratio (0 if unknown)
712 * - encoding: Set by user.
713 * - decoding: Set by libavformat.
715 AVRational sample_aspect_ratio;
717 AVDictionary *metadata;
719 #if FF_API_REORDER_PRIVATE
720 /* Intended mostly for av_read_frame() support. Not supposed to be used by */
721 /* external applications; try to use something else if at all possible. */
722 const uint8_t *cur_ptr;
726 // Timestamp generation support:
728 * Timestamp corresponding to the last dts sync point.
730 * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
731 * a DTS is received from the underlying container. Otherwise set to
732 * AV_NOPTS_VALUE by default.
734 int64_t reference_dts;
737 * Number of packets to buffer for codec probing
738 * NOT PART OF PUBLIC API
740 #define MAX_PROBE_PACKETS 2500
744 * last packet in packet_buffer for this stream when muxing.
745 * Used internally, NOT PART OF PUBLIC API, do not read or
746 * write from outside of libav*
748 struct AVPacketList *last_in_packet_buffer;
754 AVRational avg_frame_rate;
756 /*****************************************************************
757 * All fields below this line are not part of the public API. They
758 * may not be used outside of libavformat and can be changed and
760 * New public fields should be added right above.
761 *****************************************************************
765 * Number of frames that have been demuxed during av_find_stream_info()
767 int codec_info_nb_frames;
770 * Stream information used internally by av_find_stream_info()
772 #define MAX_STD_TIMEBASES (60*12+5)
775 int64_t duration_gcd;
777 double duration_error[MAX_STD_TIMEBASES];
778 int64_t codec_info_duration;
779 int nb_decoded_frames;
781 #if !FF_API_REORDER_PRIVATE
782 const uint8_t *cur_ptr;
786 // Timestamp generation support:
788 * Timestamp corresponding to the last dts sync point.
790 * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
791 * a DTS is received from the underlying container. Otherwise set to
792 * AV_NOPTS_VALUE by default.
794 int64_t reference_dts;
797 int last_IP_duration;
801 * Number of packets to buffer for codec probing
803 #define MAX_PROBE_PACKETS 2500
807 * last packet in packet_buffer for this stream when muxing.
809 struct AVPacketList *last_in_packet_buffer;
810 AVProbeData probe_data;
811 #define MAX_REORDER_DELAY 16
812 int64_t pts_buffer[MAX_REORDER_DELAY+1];
813 /* av_read_frame() support */
814 enum AVStreamParseType need_parsing;
815 struct AVCodecParserContext *parser;
817 AVIndexEntry *index_entries; /**< Only used if the format does not
818 support seeking natively. */
819 int nb_index_entries;
820 unsigned int index_entries_allocated_size;
822 int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
826 #define AV_PROGRAM_RUNNING 1
829 * New fields can be added to the end with minor version bumps.
830 * Removal, reordering and changes to existing fields require a major
832 * sizeof(AVProgram) must not be used outside libav*.
834 typedef struct AVProgram {
837 enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
838 unsigned int *stream_index;
839 unsigned int nb_stream_indexes;
840 AVDictionary *metadata;
843 #define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
844 (streams are added dynamically) */
846 typedef struct AVChapter {
847 int id; ///< unique ID to identify the chapter
848 AVRational time_base; ///< time base in which the start/end timestamps are specified
849 int64_t start, end; ///< chapter start/end time in time_base units
850 AVDictionary *metadata;
854 * Format I/O context.
855 * New fields can be added to the end with minor version bumps.
856 * Removal, reordering and changes to existing fields require a major
858 * sizeof(AVFormatContext) must not be used outside libav*, use
859 * avformat_alloc_context() to create an AVFormatContext.
861 typedef struct AVFormatContext {
863 * A class for logging and AVOptions. Set by avformat_alloc_context().
864 * Exports (de)muxer private options if they exist.
866 const AVClass *av_class;
869 * Can only be iformat or oformat, not both at the same time.
871 * decoding: set by avformat_open_input().
872 * encoding: set by the user.
874 struct AVInputFormat *iformat;
875 struct AVOutputFormat *oformat;
878 * Format private data. This is an AVOptions-enabled struct
879 * if and only if iformat/oformat.priv_class is not NULL.
886 * decoding: either set by the user before avformat_open_input() (then
887 * the user must close it manually) or set by avformat_open_input().
888 * encoding: set by the user.
890 * Do NOT set this field if AVFMT_NOFILE flag is set in
891 * iformat/oformat.flags. In such a case, the (de)muxer will handle
892 * I/O in some other way and this field will be NULL.
897 * A list of all streams in the file. New streams are created with
898 * avformat_new_stream().
900 * decoding: streams are created by libavformat in avformat_open_input().
901 * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
902 * appear in av_read_frame().
903 * encoding: streams are created by the user before avformat_write_header().
905 unsigned int nb_streams;
908 char filename[1024]; /**< input or output filename */
912 * @deprecated use 'creation_time' metadata tag instead
914 attribute_deprecated int64_t timestamp;
917 int ctx_flags; /**< Format-specific flags, see AVFMTCTX_xx */
918 #if FF_API_REORDER_PRIVATE
919 /* private data for pts handling (do not modify directly). */
921 * This buffer is only needed when packets were already buffered but
922 * not decoded, for example to get the codec parameters in MPEG
925 struct AVPacketList *packet_buffer;
929 * Decoding: position of the first frame of the component, in
930 * AV_TIME_BASE fractional seconds. NEVER set this value directly:
931 * It is deduced from the AVStream values.
936 * Decoding: duration of the stream, in AV_TIME_BASE fractional
937 * seconds. Only set this value if you know none of the individual stream
938 * durations and also do not set any of them. This is deduced from the
939 * AVStream values if not set.
945 * decoding: total file size, 0 if unknown
947 attribute_deprecated int64_t file_size;
951 * Decoding: total stream bitrate in bit/s, 0 if not
952 * available. Never set it directly if the file_size and the
953 * duration are known as Libav can compute it automatically.
957 #if FF_API_REORDER_PRIVATE
958 /* av_read_frame() support */
961 /* av_seek_frame() support */
962 int64_t data_offset; /**< offset of the first packet */
967 * use mpeg muxer private options instead
969 attribute_deprecated int mux_rate;
971 unsigned int packet_size;
973 attribute_deprecated int preload;
977 #if FF_API_LOOP_OUTPUT
978 #define AVFMT_NOOUTPUTLOOP -1
979 #define AVFMT_INFINITEOUTPUTLOOP 0
981 * number of times to loop output in formats that support it
983 * @deprecated use the 'loop' private option in the gif muxer.
985 attribute_deprecated int loop_output;
989 #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
990 #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
991 #define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
992 #define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
993 #define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
994 #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
995 #if FF_API_FLAG_RTP_HINT
996 #define AVFMT_FLAG_RTP_HINT 0x0040 ///< Deprecated, use the -movflags rtphint muxer specific AVOption instead
998 #define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
999 #define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted
1001 #if FF_API_LOOP_INPUT
1003 * @deprecated, use the 'loop' img2 demuxer private option.
1005 attribute_deprecated int loop_input;
1009 * decoding: size of data to probe; encoding: unused.
1011 unsigned int probesize;
1014 * decoding: maximum time (in AV_TIME_BASE units) during which the input should
1015 * be analyzed in avformat_find_stream_info().
1017 int max_analyze_duration;
1022 unsigned int nb_programs;
1023 AVProgram **programs;
1026 * Forced video codec_id.
1027 * Demuxing: Set by user.
1029 enum CodecID video_codec_id;
1032 * Forced audio codec_id.
1033 * Demuxing: Set by user.
1035 enum CodecID audio_codec_id;
1038 * Forced subtitle codec_id.
1039 * Demuxing: Set by user.
1041 enum CodecID subtitle_codec_id;
1044 * Maximum amount of memory in bytes to use for the index of each stream.
1045 * If the index exceeds this size, entries will be discarded as
1046 * needed to maintain a smaller size. This can lead to slower or less
1047 * accurate seeking (depends on demuxer).
1048 * Demuxers for which a full in-memory index is mandatory will ignore
1051 * demuxing: set by user
1053 unsigned int max_index_size;
1056 * Maximum amount of memory in bytes to use for buffering frames
1057 * obtained from realtime capture devices.
1059 unsigned int max_picture_buffer;
1061 unsigned int nb_chapters;
1062 AVChapter **chapters;
1065 * Flags to enable debugging.
1068 #define FF_FDEBUG_TS 0x0001
1070 #if FF_API_REORDER_PRIVATE
1072 * Raw packets from the demuxer, prior to parsing and decoding.
1073 * This buffer is used for buffering packets until the codec can
1074 * be identified, as parsing cannot be done without knowing the
1077 struct AVPacketList *raw_packet_buffer;
1078 struct AVPacketList *raw_packet_buffer_end;
1080 struct AVPacketList *packet_buffer_end;
1083 AVDictionary *metadata;
1085 #if FF_API_REORDER_PRIVATE
1087 * Remaining size available for raw_packet_buffer, in bytes.
1088 * NOT PART OF PUBLIC API
1090 #define RAW_PACKET_BUFFER_SIZE 2500000
1091 int raw_packet_buffer_remaining_size;
1095 * Start time of the stream in real world time, in microseconds
1096 * since the unix epoch (00:00 1st January 1970). That is, pts=0
1097 * in the stream was captured at this real world time.
1098 * - encoding: Set by user.
1099 * - decoding: Unused.
1101 int64_t start_time_realtime;
1104 * decoding: number of frames used to probe fps
1109 * Error recognition; higher values will detect more errors but may
1110 * misdetect some more or less valid parts as errors.
1111 * - encoding: unused
1112 * - decoding: Set by user.
1114 int error_recognition;
1117 * Custom interrupt callbacks for the I/O layer.
1119 * decoding: set by the user before avformat_open_input().
1120 * encoding: set by the user before avformat_write_header()
1121 * (mainly useful for AVFMT_NOFILE formats). The callback
1122 * should also be passed to avio_open2() if it's used to
1125 AVIOInterruptCB interrupt_callback;
1127 /*****************************************************************
1128 * All fields below this line are not part of the public API. They
1129 * may not be used outside of libavformat and can be changed and
1131 * New public fields should be added right above.
1132 *****************************************************************
1134 #if !FF_API_REORDER_PRIVATE
1136 * Raw packets from the demuxer, prior to parsing and decoding.
1137 * This buffer is used for buffering packets until the codec can
1138 * be identified, as parsing cannot be done without knowing the
1141 struct AVPacketList *raw_packet_buffer;
1142 struct AVPacketList *raw_packet_buffer_end;
1144 * Remaining size available for raw_packet_buffer, in bytes.
1146 #define RAW_PACKET_BUFFER_SIZE 2500000
1147 int raw_packet_buffer_remaining_size;
1150 * This buffer is only needed when packets were already buffered but
1151 * not decoded, for example to get the codec parameters in MPEG
1154 struct AVPacketList *packet_buffer;
1155 struct AVPacketList *packet_buffer_end;
1157 /* av_read_frame() support */
1160 /* av_seek_frame() support */
1161 int64_t data_offset; /**< offset of the first packet */
1165 typedef struct AVPacketList {
1167 struct AVPacketList *next;
1172 * @defgroup lavf_core Core functions
1175 * Functions for querying libavformat capabilities, allocating core structures,
1181 * Return the LIBAVFORMAT_VERSION_INT constant.
1183 unsigned avformat_version(void);
1186 * Return the libavformat build-time configuration.
1188 const char *avformat_configuration(void);
1191 * Return the libavformat license.
1193 const char *avformat_license(void);
1196 * Initialize libavformat and register all the muxers, demuxers and
1197 * protocols. If you do not call this function, then you can select
1198 * exactly which formats you want to support.
1200 * @see av_register_input_format()
1201 * @see av_register_output_format()
1202 * @see av_register_protocol()
1204 void av_register_all(void);
1206 void av_register_input_format(AVInputFormat *format);
1207 void av_register_output_format(AVOutputFormat *format);
1210 * Do global initialization of network components. This is optional,
1211 * but recommended, since it avoids the overhead of implicitly
1212 * doing the setup for each session.
1214 * Calling this function will become mandatory if using network
1215 * protocols at some major version bump.
1217 int avformat_network_init(void);
1220 * Undo the initialization done by avformat_network_init.
1222 int avformat_network_deinit(void);
1225 * If f is NULL, returns the first registered input format,
1226 * if f is non-NULL, returns the next registered input format after f
1227 * or NULL if f is the last one.
1229 AVInputFormat *av_iformat_next(AVInputFormat *f);
1232 * If f is NULL, returns the first registered output format,
1233 * if f is non-NULL, returns the next registered output format after f
1234 * or NULL if f is the last one.
1236 AVOutputFormat *av_oformat_next(AVOutputFormat *f);
1239 * Allocate an AVFormatContext.
1240 * avformat_free_context() can be used to free the context and everything
1241 * allocated by the framework within it.
1243 AVFormatContext *avformat_alloc_context(void);
1246 * Free an AVFormatContext and all its streams.
1247 * @param s context to free
1249 void avformat_free_context(AVFormatContext *s);
1252 * Get the AVClass for AVFormatContext. It can be used in combination with
1253 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
1255 * @see av_opt_find().
1257 const AVClass *avformat_get_class(void);
1260 * Add a new stream to a media file.
1262 * When demuxing, it is called by the demuxer in read_header(). If the
1263 * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
1264 * be called in read_packet().
1266 * When muxing, should be called by the user before avformat_write_header().
1268 * @param c If non-NULL, the AVCodecContext corresponding to the new stream
1269 * will be initialized to use this codec. This is needed for e.g. codec-specific
1270 * defaults to be set, so codec should be provided if it is known.
1272 * @return newly created stream or NULL on error.
1274 AVStream *avformat_new_stream(AVFormatContext *s, AVCodec *c);
1276 AVProgram *av_new_program(AVFormatContext *s, int id);
1283 #if FF_API_GUESS_IMG2_CODEC
1284 attribute_deprecated enum CodecID av_guess_image2_codec(const char *filename);
1288 attribute_deprecated void av_pkt_dump(FILE *f, AVPacket *pkt, int dump_payload);
1289 attribute_deprecated void av_pkt_dump_log(void *avcl, int level, AVPacket *pkt,
1295 * @addtogroup lavf_decoding
1300 * Find AVInputFormat based on the short name of the input format.
1302 AVInputFormat *av_find_input_format(const char *short_name);
1305 * Guess the file format.
1307 * @param is_opened Whether the file is already opened; determines whether
1308 * demuxers with or without AVFMT_NOFILE are probed.
1310 AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
1313 * Guess the file format.
1315 * @param is_opened Whether the file is already opened; determines whether
1316 * demuxers with or without AVFMT_NOFILE are probed.
1317 * @param score_max A probe score larger that this is required to accept a
1318 * detection, the variable is set to the actual detection
1320 * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
1321 * to retry with a larger probe buffer.
1323 AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max);
1326 * Probe a bytestream to determine the input format. Each time a probe returns
1327 * with a score that is too low, the probe buffer size is increased and another
1328 * attempt is made. When the maximum probe size is reached, the input format
1329 * with the highest score is returned.
1331 * @param pb the bytestream to probe
1332 * @param fmt the input format is put here
1333 * @param filename the filename of the stream
1334 * @param logctx the log context
1335 * @param offset the offset within the bytestream to probe from
1336 * @param max_probe_size the maximum probe buffer size (zero for default)
1337 * @return 0 in case of success, a negative value corresponding to an
1338 * AVERROR code otherwise
1340 int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt,
1341 const char *filename, void *logctx,
1342 unsigned int offset, unsigned int max_probe_size);
1344 #if FF_API_FORMAT_PARAMETERS
1346 * Allocate all the structures needed to read an input stream.
1347 * This does not open the needed codecs for decoding the stream[s].
1348 * @deprecated use avformat_open_input instead.
1350 attribute_deprecated int av_open_input_stream(AVFormatContext **ic_ptr,
1351 AVIOContext *pb, const char *filename,
1352 AVInputFormat *fmt, AVFormatParameters *ap);
1355 * Open a media file as input. The codecs are not opened. Only the file
1356 * header (if present) is read.
1358 * @param ic_ptr The opened media file handle is put here.
1359 * @param filename filename to open
1360 * @param fmt If non-NULL, force the file format to use.
1361 * @param buf_size optional buffer size (zero if default is OK)
1362 * @param ap Additional parameters needed when opening the file
1363 * (NULL if default).
1364 * @return 0 if OK, AVERROR_xxx otherwise
1366 * @deprecated use avformat_open_input instead.
1368 attribute_deprecated int av_open_input_file(AVFormatContext **ic_ptr, const char *filename,
1371 AVFormatParameters *ap);
1375 * Open an input stream and read the header. The codecs are not opened.
1376 * The stream must be closed with av_close_input_file().
1378 * @param ps Pointer to user-supplied AVFormatContext (allocated by avformat_alloc_context).
1379 * May be a pointer to NULL, in which case an AVFormatContext is allocated by this
1380 * function and written into ps.
1381 * Note that a user-supplied AVFormatContext will be freed on failure.
1382 * @param filename Name of the stream to open.
1383 * @param fmt If non-NULL, this parameter forces a specific input format.
1384 * Otherwise the format is autodetected.
1385 * @param options A dictionary filled with AVFormatContext and demuxer-private options.
1386 * On return this parameter will be destroyed and replaced with a dict containing
1387 * options that were not found. May be NULL.
1389 * @return 0 on success, a negative AVERROR on failure.
1391 * @note If you want to use custom IO, preallocate the format context and set its pb field.
1393 int avformat_open_input(AVFormatContext **ps, const char *filename, AVInputFormat *fmt, AVDictionary **options);
1395 #if FF_API_FORMAT_PARAMETERS
1397 * Read packets of a media file to get stream information. This
1398 * is useful for file formats with no headers such as MPEG. This
1399 * function also computes the real framerate in case of MPEG-2 repeat
1401 * The logical file position is not changed by this function;
1402 * examined packets may be buffered for later processing.
1404 * @param ic media file handle
1405 * @return >=0 if OK, AVERROR_xxx on error
1406 * @todo Let the user decide somehow what information is needed so that
1407 * we do not waste time getting stuff the user does not need.
1409 * @deprecated use avformat_find_stream_info.
1411 attribute_deprecated
1412 int av_find_stream_info(AVFormatContext *ic);
1416 * Read packets of a media file to get stream information. This
1417 * is useful for file formats with no headers such as MPEG. This
1418 * function also computes the real framerate in case of MPEG-2 repeat
1420 * The logical file position is not changed by this function;
1421 * examined packets may be buffered for later processing.
1423 * @param ic media file handle
1424 * @param options If non-NULL, an ic.nb_streams long array of pointers to
1425 * dictionaries, where i-th member contains options for
1426 * codec corresponding to i-th stream.
1427 * On return each dictionary will be filled with options that were not found.
1428 * @return >=0 if OK, AVERROR_xxx on error
1430 * @note this function isn't guaranteed to open all the codecs, so
1431 * options being non-empty at return is a perfectly normal behavior.
1433 * @todo Let the user decide somehow what information is needed so that
1434 * we do not waste time getting stuff the user does not need.
1436 int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options);
1439 * Find the "best" stream in the file.
1440 * The best stream is determined according to various heuristics as the most
1441 * likely to be what the user expects.
1442 * If the decoder parameter is non-NULL, av_find_best_stream will find the
1443 * default decoder for the stream's codec; streams for which no decoder can
1444 * be found are ignored.
1446 * @param ic media file handle
1447 * @param type stream type: video, audio, subtitles, etc.
1448 * @param wanted_stream_nb user-requested stream number,
1449 * or -1 for automatic selection
1450 * @param related_stream try to find a stream related (eg. in the same
1451 * program) to this one, or -1 if none
1452 * @param decoder_ret if non-NULL, returns the decoder for the
1454 * @param flags flags; none are currently defined
1455 * @return the non-negative stream number in case of success,
1456 * AVERROR_STREAM_NOT_FOUND if no stream with the requested type
1458 * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
1459 * @note If av_find_best_stream returns successfully and decoder_ret is not
1460 * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
1462 int av_find_best_stream(AVFormatContext *ic,
1463 enum AVMediaType type,
1464 int wanted_stream_nb,
1466 AVCodec **decoder_ret,
1470 * Read a transport packet from a media file.
1472 * This function is obsolete and should never be used.
1473 * Use av_read_frame() instead.
1475 * @param s media file handle
1476 * @param pkt is filled
1477 * @return 0 if OK, AVERROR_xxx on error
1479 int av_read_packet(AVFormatContext *s, AVPacket *pkt);
1482 * Return the next frame of a stream.
1483 * This function returns what is stored in the file, and does not validate
1484 * that what is there are valid frames for the decoder. It will split what is
1485 * stored in the file into frames and return one for each call. It will not
1486 * omit invalid data between valid frames so as to give the decoder the maximum
1487 * information possible for decoding.
1489 * The returned packet is valid
1490 * until the next av_read_frame() or until av_close_input_file() and
1491 * must be freed with av_free_packet. For video, the packet contains
1492 * exactly one frame. For audio, it contains an integer number of
1493 * frames if each frame has a known fixed size (e.g. PCM or ADPCM
1494 * data). If the audio frames have a variable size (e.g. MPEG audio),
1495 * then it contains one frame.
1497 * pkt->pts, pkt->dts and pkt->duration are always set to correct
1498 * values in AVStream.time_base units (and guessed if the format cannot
1499 * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
1500 * has B-frames, so it is better to rely on pkt->dts if you do not
1501 * decompress the payload.
1503 * @return 0 if OK, < 0 on error or end of file
1505 int av_read_frame(AVFormatContext *s, AVPacket *pkt);
1508 * Seek to the keyframe at timestamp.
1509 * 'timestamp' in 'stream_index'.
1510 * @param stream_index If stream_index is (-1), a default
1511 * stream is selected, and timestamp is automatically converted
1512 * from AV_TIME_BASE units to the stream specific time_base.
1513 * @param timestamp Timestamp in AVStream.time_base units
1514 * or, if no stream is specified, in AV_TIME_BASE units.
1515 * @param flags flags which select direction and seeking mode
1516 * @return >= 0 on success
1518 int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
1522 * Seek to timestamp ts.
1523 * Seeking will be done so that the point from which all active streams
1524 * can be presented successfully will be closest to ts and within min/max_ts.
1525 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
1527 * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
1528 * are the file position (this may not be supported by all demuxers).
1529 * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
1530 * in the stream with stream_index (this may not be supported by all demuxers).
1531 * Otherwise all timestamps are in units of the stream selected by stream_index
1532 * or if stream_index is -1, in AV_TIME_BASE units.
1533 * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
1534 * keyframes (this may not be supported by all demuxers).
1536 * @param stream_index index of the stream which is used as time base reference
1537 * @param min_ts smallest acceptable timestamp
1538 * @param ts target timestamp
1539 * @param max_ts largest acceptable timestamp
1540 * @param flags flags
1541 * @return >=0 on success, error code otherwise
1543 * @note This is part of the new seek API which is still under construction.
1544 * Thus do not use this yet. It may change at any time, do not expect
1545 * ABI compatibility yet!
1547 int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
1550 * Start playing a network-based stream (e.g. RTSP stream) at the
1553 int av_read_play(AVFormatContext *s);
1556 * Pause a network-based stream (e.g. RTSP stream).
1558 * Use av_read_play() to resume it.
1560 int av_read_pause(AVFormatContext *s);
1562 #if FF_API_FORMAT_PARAMETERS
1564 * Free a AVFormatContext allocated by av_open_input_stream.
1565 * @param s context to free
1566 * @deprecated use av_close_input_file()
1568 attribute_deprecated
1569 void av_close_input_stream(AVFormatContext *s);
1572 #if FF_API_CLOSE_INPUT_FILE
1574 * @deprecated use avformat_close_input()
1575 * Close a media file (but not its codecs).
1577 * @param s media file handle
1579 attribute_deprecated
1580 void av_close_input_file(AVFormatContext *s);
1584 * Close an opened input AVFormatContext. Free it and all its contents
1585 * and set *s to NULL.
1587 void avformat_close_input(AVFormatContext **s);
1592 #if FF_API_NEW_STREAM
1594 * Add a new stream to a media file.
1596 * Can only be called in the read_header() function. If the flag
1597 * AVFMTCTX_NOHEADER is in the format context, then new streams
1598 * can be added in read_packet too.
1600 * @param s media file handle
1601 * @param id file-format-dependent stream ID
1603 attribute_deprecated
1604 AVStream *av_new_stream(AVFormatContext *s, int id);
1607 #if FF_API_SET_PTS_INFO
1609 * @deprecated this function is not supposed to be called outside of lavf
1611 attribute_deprecated
1612 void av_set_pts_info(AVStream *s, int pts_wrap_bits,
1613 unsigned int pts_num, unsigned int pts_den);
1616 #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
1617 #define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
1618 #define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
1619 #define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
1621 #if FF_API_SEEK_PUBLIC
1622 attribute_deprecated
1623 int av_seek_frame_binary(AVFormatContext *s, int stream_index,
1624 int64_t target_ts, int flags);
1625 attribute_deprecated
1626 void av_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp);
1627 attribute_deprecated
1628 int64_t av_gen_search(AVFormatContext *s, int stream_index,
1629 int64_t target_ts, int64_t pos_min,
1630 int64_t pos_max, int64_t pos_limit,
1631 int64_t ts_min, int64_t ts_max,
1632 int flags, int64_t *ts_ret,
1633 int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
1636 #if FF_API_FORMAT_PARAMETERS
1638 * @deprecated pass the options to avformat_write_header directly.
1640 attribute_deprecated int av_set_parameters(AVFormatContext *s, AVFormatParameters *ap);
1644 * @addtogroup lavf_encoding
1648 * Allocate the stream private data and write the stream header to
1649 * an output media file.
1651 * @param s Media file handle, must be allocated with avformat_alloc_context().
1652 * Its oformat field must be set to the desired output format;
1653 * Its pb field must be set to an already openened AVIOContext.
1654 * @param options An AVDictionary filled with AVFormatContext and muxer-private options.
1655 * On return this parameter will be destroyed and replaced with a dict containing
1656 * options that were not found. May be NULL.
1658 * @return 0 on success, negative AVERROR on failure.
1660 * @see av_opt_find, av_dict_set, avio_open, av_oformat_next.
1662 int avformat_write_header(AVFormatContext *s, AVDictionary **options);
1664 #if FF_API_FORMAT_PARAMETERS
1666 * Allocate the stream private data and write the stream header to an
1667 * output media file.
1668 * @note: this sets stream time-bases, if possible to stream->codec->time_base
1669 * but for some formats it might also be some other time base
1671 * @param s media file handle
1672 * @return 0 if OK, AVERROR_xxx on error
1674 * @deprecated use avformat_write_header.
1676 attribute_deprecated int av_write_header(AVFormatContext *s);
1680 * Write a packet to an output media file.
1682 * The packet shall contain one audio or video frame.
1683 * The packet must be correctly interleaved according to the container
1684 * specification, if not then av_interleaved_write_frame must be used.
1686 * @param s media file handle
1687 * @param pkt The packet, which contains the stream_index, buf/buf_size,
1689 * @return < 0 on error, = 0 if OK, 1 if end of stream wanted
1691 int av_write_frame(AVFormatContext *s, AVPacket *pkt);
1694 * Write a packet to an output media file ensuring correct interleaving.
1696 * The packet must contain one audio or video frame.
1697 * If the packets are already correctly interleaved, the application should
1698 * call av_write_frame() instead as it is slightly faster. It is also important
1699 * to keep in mind that completely non-interleaved input will need huge amounts
1700 * of memory to interleave with this, so it is preferable to interleave at the
1703 * @param s media file handle
1704 * @param pkt The packet, which contains the stream_index, buf/buf_size,
1706 * @return < 0 on error, = 0 if OK, 1 if end of stream wanted
1708 int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
1711 * Interleave a packet per dts in an output media file.
1713 * Packets with pkt->destruct == av_destruct_packet will be freed inside this
1714 * function, so they cannot be used after it. Note that calling av_free_packet()
1715 * on them is still safe.
1717 * @param s media file handle
1718 * @param out the interleaved packet will be output here
1719 * @param pkt the input packet
1720 * @param flush 1 if no further packets are available as input and all
1721 * remaining packets should be output
1722 * @return 1 if a packet was output, 0 if no packet could be output,
1723 * < 0 if an error occurred
1725 int av_interleave_packet_per_dts(AVFormatContext *s, AVPacket *out,
1726 AVPacket *pkt, int flush);
1729 * Write the stream trailer to an output media file and free the
1730 * file private data.
1732 * May only be called after a successful call to av_write_header.
1734 * @param s media file handle
1735 * @return 0 if OK, AVERROR_xxx on error
1737 int av_write_trailer(AVFormatContext *s);
1740 * Return the output format in the list of registered output formats
1741 * which best matches the provided parameters, or return NULL if
1742 * there is no match.
1744 * @param short_name if non-NULL checks if short_name matches with the
1745 * names of the registered formats
1746 * @param filename if non-NULL checks if filename terminates with the
1747 * extensions of the registered formats
1748 * @param mime_type if non-NULL checks if mime_type matches with the
1749 * MIME type of the registered formats
1751 AVOutputFormat *av_guess_format(const char *short_name,
1752 const char *filename,
1753 const char *mime_type);
1756 * Guess the codec ID based upon muxer and filename.
1758 enum CodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
1759 const char *filename, const char *mime_type,
1760 enum AVMediaType type);
1768 * @defgroup lavf_misc Utility functions
1772 * Miscelaneous utility functions related to both muxing and demuxing
1777 * Send a nice hexadecimal dump of a buffer to the specified file stream.
1779 * @param f The file stream pointer where the dump should be sent to.
1781 * @param size buffer size
1783 * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2
1785 void av_hex_dump(FILE *f, uint8_t *buf, int size);
1788 * Send a nice hexadecimal dump of a buffer to the log.
1790 * @param avcl A pointer to an arbitrary struct of which the first field is a
1791 * pointer to an AVClass struct.
1792 * @param level The importance level of the message, lower values signifying
1793 * higher importance.
1795 * @param size buffer size
1797 * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2
1799 void av_hex_dump_log(void *avcl, int level, uint8_t *buf, int size);
1802 * Send a nice dump of a packet to the specified file stream.
1804 * @param f The file stream pointer where the dump should be sent to.
1805 * @param pkt packet to dump
1806 * @param dump_payload True if the payload must be displayed, too.
1807 * @param st AVStream that the packet belongs to
1809 void av_pkt_dump2(FILE *f, AVPacket *pkt, int dump_payload, AVStream *st);
1813 * Send a nice dump of a packet to the log.
1815 * @param avcl A pointer to an arbitrary struct of which the first field is a
1816 * pointer to an AVClass struct.
1817 * @param level The importance level of the message, lower values signifying
1818 * higher importance.
1819 * @param pkt packet to dump
1820 * @param dump_payload True if the payload must be displayed, too.
1821 * @param st AVStream that the packet belongs to
1823 void av_pkt_dump_log2(void *avcl, int level, AVPacket *pkt, int dump_payload,
1827 * Get the CodecID for the given codec tag tag.
1828 * If no codec id is found returns CODEC_ID_NONE.
1830 * @param tags list of supported codec_id-codec_tag pairs, as stored
1831 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
1833 enum CodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
1836 * Get the codec tag for the given codec id id.
1837 * If no codec tag is found returns 0.
1839 * @param tags list of supported codec_id-codec_tag pairs, as stored
1840 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
1842 unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum CodecID id);
1844 int av_find_default_stream_index(AVFormatContext *s);
1847 * Get the index for a specific timestamp.
1848 * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
1849 * to the timestamp which is <= the requested one, if backward
1850 * is 0, then it will be >=
1851 * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
1852 * @return < 0 if no such timestamp could be found
1854 int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
1857 * Add an index entry into a sorted list. Update the entry if the list
1858 * already contains it.
1860 * @param timestamp timestamp in the time base of the given stream
1862 int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
1863 int size, int distance, int flags);
1867 * Split a URL string into components.
1869 * The pointers to buffers for storing individual components may be null,
1870 * in order to ignore that component. Buffers for components not found are
1871 * set to empty strings. If the port is not found, it is set to a negative
1874 * @param proto the buffer for the protocol
1875 * @param proto_size the size of the proto buffer
1876 * @param authorization the buffer for the authorization
1877 * @param authorization_size the size of the authorization buffer
1878 * @param hostname the buffer for the host name
1879 * @param hostname_size the size of the hostname buffer
1880 * @param port_ptr a pointer to store the port number in
1881 * @param path the buffer for the path
1882 * @param path_size the size of the path buffer
1883 * @param url the URL to split
1885 void av_url_split(char *proto, int proto_size,
1886 char *authorization, int authorization_size,
1887 char *hostname, int hostname_size,
1889 char *path, int path_size,
1892 #if FF_API_DUMP_FORMAT
1893 attribute_deprecated void dump_format(AVFormatContext *ic,
1899 void av_dump_format(AVFormatContext *ic,
1904 #if FF_API_PARSE_DATE
1906 * Parse datestr and return a corresponding number of microseconds.
1908 * @param datestr String representing a date or a duration.
1909 * See av_parse_time() for the syntax of the provided string.
1910 * @deprecated in favor of av_parse_time()
1912 attribute_deprecated
1913 int64_t parse_date(const char *datestr, int duration);
1917 * Get the current time in microseconds.
1919 int64_t av_gettime(void);
1921 #if FF_API_FIND_INFO_TAG
1923 * @deprecated use av_find_info_tag in libavutil instead.
1925 attribute_deprecated int find_info_tag(char *arg, int arg_size, const char *tag1, const char *info);
1929 * Return in 'buf' the path with '%d' replaced by a number.
1931 * Also handles the '%0nd' format where 'n' is the total number
1932 * of digits and '%%'.
1934 * @param buf destination buffer
1935 * @param buf_size destination buffer size
1936 * @param path numbered sequence string
1937 * @param number frame number
1938 * @return 0 if OK, -1 on format error
1940 int av_get_frame_filename(char *buf, int buf_size,
1941 const char *path, int number);
1944 * Check whether filename actually is a numbered sequence generator.
1946 * @param filename possible numbered sequence string
1947 * @return 1 if a valid numbered sequence string, 0 otherwise
1949 int av_filename_number_test(const char *filename);
1952 * Generate an SDP for an RTP session.
1954 * @param ac array of AVFormatContexts describing the RTP streams. If the
1955 * array is composed by only one context, such context can contain
1956 * multiple AVStreams (one AVStream per RTP stream). Otherwise,
1957 * all the contexts in the array (an AVCodecContext per RTP stream)
1958 * must contain only one AVStream.
1959 * @param n_files number of AVCodecContexts contained in ac
1960 * @param buf buffer where the SDP will be stored (must be allocated by
1962 * @param size the size of the buffer
1963 * @return 0 if OK, AVERROR_xxx on error
1965 int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size);
1967 #if FF_API_SDP_CREATE
1968 attribute_deprecated int avf_sdp_create(AVFormatContext *ac[], int n_files, char *buff, int size);
1972 * Return a positive value if the given filename has one of the given
1973 * extensions, 0 otherwise.
1975 * @param extensions a comma-separated list of filename extensions
1977 int av_match_ext(const char *filename, const char *extensions);
1980 * Test if the given container can store a codec.
1982 * @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
1984 * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
1985 * A negative number if this information is not available.
1987 int avformat_query_codec(AVOutputFormat *ofmt, enum CodecID codec_id, int std_compliance);
1993 #endif /* AVFORMAT_AVFORMAT_H */