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 #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 */
383 #define AVFMT_TS_NONSTRICT 0x8000000 /**< Format does not require strictly
384 increasing timestamps, but they must
385 still be monotonic */
388 * @addtogroup lavf_encoding
391 typedef struct AVOutputFormat {
394 * Descriptive name for the format, meant to be more human-readable
395 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
398 const char *long_name;
399 const char *mime_type;
400 const char *extensions; /**< comma-separated filename extensions */
402 * size of private data so that it can be allocated in the wrapper
406 enum CodecID audio_codec; /**< default audio codec */
407 enum CodecID video_codec; /**< default video codec */
408 int (*write_header)(struct AVFormatContext *);
409 int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
410 int (*write_trailer)(struct AVFormatContext *);
412 * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_RAWPICTURE,
413 * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
414 * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS
420 int (*interleave_packet)(struct AVFormatContext *, AVPacket *out,
421 AVPacket *in, int flush);
424 * List of supported codec_id-codec_tag pairs, ordered by "better
425 * choice first". The arrays are all terminated by CODEC_ID_NONE.
427 const struct AVCodecTag * const *codec_tag;
429 enum CodecID subtitle_codec; /**< default subtitle codec */
431 #if FF_API_OLD_METADATA2
432 const AVMetadataConv *metadata_conv;
435 const AVClass *priv_class; ///< AVClass for the private context
438 * Test if the given codec can be stored in this container.
440 * @return 1 if the codec is supported, 0 if it is not.
441 * A negative number if unknown.
443 int (*query_codec)(enum CodecID id, int std_compliance);
445 void (*get_output_timestamp)(struct AVFormatContext *s, int stream,
446 int64_t *dts, int64_t *wall);
449 struct AVOutputFormat *next;
456 * @addtogroup lavf_decoding
459 typedef struct AVInputFormat {
461 * A comma separated list of short names for the format. New names
462 * may be appended with a minor bump.
467 * Descriptive name for the format, meant to be more human-readable
468 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
471 const char *long_name;
474 * Size of private data so that it can be allocated in the wrapper.
479 * Tell if a given file has a chance of being parsed as this format.
480 * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
481 * big so you do not have to check for that unless you need more.
483 int (*read_probe)(AVProbeData *);
486 * Read the format header and initialize the AVFormatContext
487 * structure. Return 0 if OK. 'ap' if non-NULL contains
488 * additional parameters. Only used in raw format right
489 * now. 'av_new_stream' should be called to create new streams.
491 int (*read_header)(struct AVFormatContext *,
492 AVFormatParameters *ap);
495 * Read one packet and put it in 'pkt'. pts and flags are also
496 * set. 'av_new_stream' can be called only if the flag
497 * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
498 * background thread).
499 * @return 0 on success, < 0 on error.
500 * When returning an error, pkt must not have been allocated
501 * or must be freed before returning
503 int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
506 * Close the stream. The AVFormatContext and AVStreams are not
507 * freed by this function
509 int (*read_close)(struct AVFormatContext *);
513 * Seek to a given timestamp relative to the frames in
514 * stream component stream_index.
515 * @param stream_index Must not be -1.
516 * @param flags Selects which direction should be preferred if no exact
517 * match is available.
518 * @return >= 0 on success (but not necessarily the new offset)
520 attribute_deprecated int (*read_seek)(struct AVFormatContext *,
521 int stream_index, int64_t timestamp, int flags);
524 * Get the next timestamp in stream[stream_index].time_base units.
525 * @return the timestamp or AV_NOPTS_VALUE if an error occurred
527 int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
528 int64_t *pos, int64_t pos_limit);
531 * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
532 * AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
533 * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK.
538 * If extensions are defined, then no probe is done. You should
539 * usually not use extension format guessing because it is not
542 const char *extensions;
545 * General purpose read-only value that the format can use.
550 * Start/resume playing - only meaningful if using a network-based format
553 int (*read_play)(struct AVFormatContext *);
556 * Pause playing - only meaningful if using a network-based format
559 int (*read_pause)(struct AVFormatContext *);
561 const struct AVCodecTag * const *codec_tag;
564 * Seek to timestamp ts.
565 * Seeking will be done so that the point from which all active streams
566 * can be presented successfully will be closest to ts and within min/max_ts.
567 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
569 int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
571 #if FF_API_OLD_METADATA2
572 const AVMetadataConv *metadata_conv;
575 const AVClass *priv_class; ///< AVClass for the private context
578 struct AVInputFormat *next;
584 enum AVStreamParseType {
586 AVSTREAM_PARSE_FULL, /**< full parsing and repack */
587 AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
588 AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
589 AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
592 typedef struct AVIndexEntry {
594 int64_t timestamp; /**<
595 * Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are available
596 * when seeking to this entry. That means preferable PTS on keyframe based formats.
597 * But demuxers can choose to store a different timestamp, if it is more convenient for the implementation or nothing better
600 #define AVINDEX_KEYFRAME 0x0001
602 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).
603 int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
606 #define AV_DISPOSITION_DEFAULT 0x0001
607 #define AV_DISPOSITION_DUB 0x0002
608 #define AV_DISPOSITION_ORIGINAL 0x0004
609 #define AV_DISPOSITION_COMMENT 0x0008
610 #define AV_DISPOSITION_LYRICS 0x0010
611 #define AV_DISPOSITION_KARAOKE 0x0020
614 * Track should be used during playback by default.
615 * Useful for subtitle track that should be displayed
616 * even when user did not explicitly ask for subtitles.
618 #define AV_DISPOSITION_FORCED 0x0040
619 #define AV_DISPOSITION_HEARING_IMPAIRED 0x0080 /**< stream for hearing impaired audiences */
620 #define AV_DISPOSITION_VISUAL_IMPAIRED 0x0100 /**< stream for visual impaired audiences */
621 #define AV_DISPOSITION_CLEAN_EFFECTS 0x0200 /**< stream without voice */
625 * New fields can be added to the end with minor version bumps.
626 * Removal, reordering and changes to existing fields require a major
628 * sizeof(AVStream) must not be used outside libav*.
630 typedef struct AVStream {
631 int index; /**< stream index in AVFormatContext */
632 int id; /**< format-specific stream ID */
633 AVCodecContext *codec; /**< codec context */
635 * Real base framerate of the stream.
636 * This is the lowest framerate with which all timestamps can be
637 * represented accurately (it is the least common multiple of all
638 * framerates in the stream). Note, this value is just a guess!
639 * For example, if the time base is 1/90000 and all frames have either
640 * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
642 AVRational r_frame_rate;
645 #if FF_API_REORDER_PRIVATE
646 /* internal data used in av_find_stream_info() */
651 * encoding: pts generation when outputting stream
656 * This is the fundamental unit of time (in seconds) in terms
657 * of which frame timestamps are represented. For fixed-fps content,
658 * time base should be 1/framerate and timestamp increments should be 1.
659 * decoding: set by libavformat
660 * encoding: set by libavformat in av_write_header
662 AVRational time_base;
663 #if FF_API_REORDER_PRIVATE
664 int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
666 #if FF_API_STREAM_COPY
667 /* ffmpeg.c private use */
668 attribute_deprecated int stream_copy; /**< If set, just copy stream. */
670 enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
672 #if FF_API_AVSTREAM_QUALITY
673 //FIXME move stuff to a flags field?
675 * Quality, as it has been removed from AVCodecContext and put in AVVideoFrame.
676 * MN: dunno if that is the right place for it
678 attribute_deprecated float quality;
682 * Decoding: pts of the first frame of the stream in presentation order, in stream time base.
683 * Only set this if you are absolutely 100% sure that the value you set
684 * it to really is the pts of the first frame.
685 * This may be undefined (AV_NOPTS_VALUE).
686 * @note The ASF header does NOT contain a correct start_time the ASF
687 * demuxer must NOT set this.
692 * Decoding: duration of the stream, in stream time base.
693 * If a source file does not specify a duration, but does specify
694 * a bitrate, this value will be estimated from bitrate and file size.
698 #if FF_API_REORDER_PRIVATE
699 /* av_read_frame() support */
700 enum AVStreamParseType need_parsing;
701 struct AVCodecParserContext *parser;
704 int last_IP_duration;
706 /* av_seek_frame() support */
707 AVIndexEntry *index_entries; /**< Only used if the format does not
708 support seeking natively. */
709 int nb_index_entries;
710 unsigned int index_entries_allocated_size;
713 int64_t nb_frames; ///< number of frames in this stream if known or 0
715 int disposition; /**< AV_DISPOSITION_* bit field */
717 #if FF_API_REORDER_PRIVATE
718 AVProbeData probe_data;
719 #define MAX_REORDER_DELAY 16
720 int64_t pts_buffer[MAX_REORDER_DELAY+1];
724 * sample aspect ratio (0 if unknown)
725 * - encoding: Set by user.
726 * - decoding: Set by libavformat.
728 AVRational sample_aspect_ratio;
730 AVDictionary *metadata;
732 #if FF_API_REORDER_PRIVATE
733 /* Intended mostly for av_read_frame() support. Not supposed to be used by */
734 /* external applications; try to use something else if at all possible. */
735 const uint8_t *cur_ptr;
739 // Timestamp generation support:
741 * Timestamp corresponding to the last dts sync point.
743 * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
744 * a DTS is received from the underlying container. Otherwise set to
745 * AV_NOPTS_VALUE by default.
747 int64_t reference_dts;
750 * Number of packets to buffer for codec probing
751 * NOT PART OF PUBLIC API
753 #define MAX_PROBE_PACKETS 2500
757 * last packet in packet_buffer for this stream when muxing.
758 * Used internally, NOT PART OF PUBLIC API, do not read or
759 * write from outside of libav*
761 struct AVPacketList *last_in_packet_buffer;
767 AVRational avg_frame_rate;
769 /*****************************************************************
770 * All fields below this line are not part of the public API. They
771 * may not be used outside of libavformat and can be changed and
773 * New public fields should be added right above.
774 *****************************************************************
778 * Number of frames that have been demuxed during av_find_stream_info()
780 int codec_info_nb_frames;
784 * This is the MPEG-TS stream identifier +1
787 int stream_identifier;
789 int64_t interleaver_chunk_size;
790 int64_t interleaver_chunk_duration;
793 * Stream information used internally by av_find_stream_info()
795 #define MAX_STD_TIMEBASES (60*12+5)
798 int64_t duration_gcd;
800 double duration_error[2][2][MAX_STD_TIMEBASES];
801 int64_t codec_info_duration;
802 int nb_decoded_frames;
806 * flag to indicate that probing is requested
807 * NOT PART OF PUBLIC API
810 #if !FF_API_REORDER_PRIVATE
811 const uint8_t *cur_ptr;
815 // Timestamp generation support:
817 * Timestamp corresponding to the last dts sync point.
819 * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
820 * a DTS is received from the underlying container. Otherwise set to
821 * AV_NOPTS_VALUE by default.
823 int64_t reference_dts;
826 int last_IP_duration;
830 * Number of packets to buffer for codec probing
832 #define MAX_PROBE_PACKETS 2500
836 * last packet in packet_buffer for this stream when muxing.
838 struct AVPacketList *last_in_packet_buffer;
839 AVProbeData probe_data;
840 #define MAX_REORDER_DELAY 16
841 int64_t pts_buffer[MAX_REORDER_DELAY+1];
842 /* av_read_frame() support */
843 enum AVStreamParseType need_parsing;
844 struct AVCodecParserContext *parser;
846 AVIndexEntry *index_entries; /**< Only used if the format does not
847 support seeking natively. */
848 int nb_index_entries;
849 unsigned int index_entries_allocated_size;
851 int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
855 #define AV_PROGRAM_RUNNING 1
858 * New fields can be added to the end with minor version bumps.
859 * Removal, reordering and changes to existing fields require a major
861 * sizeof(AVProgram) must not be used outside libav*.
863 typedef struct AVProgram {
866 enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
867 unsigned int *stream_index;
868 unsigned int nb_stream_indexes;
869 AVDictionary *metadata;
876 #define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
877 (streams are added dynamically) */
879 typedef struct AVChapter {
880 int id; ///< unique ID to identify the chapter
881 AVRational time_base; ///< time base in which the start/end timestamps are specified
882 int64_t start, end; ///< chapter start/end time in time_base units
883 AVDictionary *metadata;
887 * Format I/O context.
888 * New fields can be added to the end with minor version bumps.
889 * Removal, reordering and changes to existing fields require a major
891 * sizeof(AVFormatContext) must not be used outside libav*, use
892 * avformat_alloc_context() to create an AVFormatContext.
894 typedef struct AVFormatContext {
896 * A class for logging and AVOptions. Set by avformat_alloc_context().
897 * Exports (de)muxer private options if they exist.
899 const AVClass *av_class;
902 * Can only be iformat or oformat, not both at the same time.
904 * decoding: set by avformat_open_input().
905 * encoding: set by the user.
907 struct AVInputFormat *iformat;
908 struct AVOutputFormat *oformat;
911 * Format private data. This is an AVOptions-enabled struct
912 * if and only if iformat/oformat.priv_class is not NULL.
919 * decoding: either set by the user before avformat_open_input() (then
920 * the user must close it manually) or set by avformat_open_input().
921 * encoding: set by the user.
923 * Do NOT set this field if AVFMT_NOFILE flag is set in
924 * iformat/oformat.flags. In such a case, the (de)muxer will handle
925 * I/O in some other way and this field will be NULL.
930 * A list of all streams in the file. New streams are created with
931 * avformat_new_stream().
933 * decoding: streams are created by libavformat in avformat_open_input().
934 * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
935 * appear in av_read_frame().
936 * encoding: streams are created by the user before avformat_write_header().
938 unsigned int nb_streams;
941 char filename[1024]; /**< input or output filename */
945 * @deprecated use 'creation_time' metadata tag instead
947 attribute_deprecated int64_t timestamp;
950 int ctx_flags; /**< Format-specific flags, see AVFMTCTX_xx */
951 #if FF_API_REORDER_PRIVATE
952 /* private data for pts handling (do not modify directly). */
954 * This buffer is only needed when packets were already buffered but
955 * not decoded, for example to get the codec parameters in MPEG
958 struct AVPacketList *packet_buffer;
962 * Decoding: position of the first frame of the component, in
963 * AV_TIME_BASE fractional seconds. NEVER set this value directly:
964 * It is deduced from the AVStream values.
969 * Decoding: duration of the stream, in AV_TIME_BASE fractional
970 * seconds. Only set this value if you know none of the individual stream
971 * durations and also do not set any of them. This is deduced from the
972 * AVStream values if not set.
978 * decoding: total file size, 0 if unknown
980 attribute_deprecated int64_t file_size;
984 * Decoding: total stream bitrate in bit/s, 0 if not
985 * available. Never set it directly if the file_size and the
986 * duration are known as FFmpeg can compute it automatically.
990 #if FF_API_REORDER_PRIVATE
991 /* av_read_frame() support */
994 /* av_seek_frame() support */
995 int64_t data_offset; /**< offset of the first packet */
1000 * use mpeg muxer private options instead
1002 attribute_deprecated int mux_rate;
1004 unsigned int packet_size;
1006 attribute_deprecated int preload;
1010 #if FF_API_LOOP_OUTPUT
1011 #define AVFMT_NOOUTPUTLOOP -1
1012 #define AVFMT_INFINITEOUTPUTLOOP 0
1014 * number of times to loop output in formats that support it
1016 * @deprecated use the 'loop' private option in the gif muxer.
1018 attribute_deprecated int loop_output;
1022 #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
1023 #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
1024 #define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
1025 #define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
1026 #define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
1027 #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
1028 #if FF_API_FLAG_RTP_HINT
1029 #define AVFMT_FLAG_RTP_HINT 0x0040 ///< Deprecated, use the -movflags rtphint muxer specific AVOption instead
1031 #define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
1032 #define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted
1033 #define AVFMT_FLAG_MP4A_LATM 0x8000 ///< Enable RTP MP4A-LATM payload
1034 #define AVFMT_FLAG_SORT_DTS 0x10000 ///< try to interleave outputted packets by dts (using this flag can slow demuxing down)
1035 #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)
1036 #define AVFMT_FLAG_KEEP_SIDE_DATA 0x40000 ///< Dont merge side data but keep it seperate.
1038 #if FF_API_LOOP_INPUT
1040 * @deprecated, use the 'loop' img2 demuxer private option.
1042 attribute_deprecated int loop_input;
1046 * decoding: size of data to probe; encoding: unused.
1048 unsigned int probesize;
1051 * decoding: maximum time (in AV_TIME_BASE units) during which the input should
1052 * be analyzed in avformat_find_stream_info().
1054 int max_analyze_duration;
1059 unsigned int nb_programs;
1060 AVProgram **programs;
1063 * Forced video codec_id.
1064 * Demuxing: Set by user.
1066 enum CodecID video_codec_id;
1069 * Forced audio codec_id.
1070 * Demuxing: Set by user.
1072 enum CodecID audio_codec_id;
1075 * Forced subtitle codec_id.
1076 * Demuxing: Set by user.
1078 enum CodecID subtitle_codec_id;
1081 * Maximum amount of memory in bytes to use for the index of each stream.
1082 * If the index exceeds this size, entries will be discarded as
1083 * needed to maintain a smaller size. This can lead to slower or less
1084 * accurate seeking (depends on demuxer).
1085 * Demuxers for which a full in-memory index is mandatory will ignore
1088 * demuxing: set by user
1090 unsigned int max_index_size;
1093 * Maximum amount of memory in bytes to use for buffering frames
1094 * obtained from realtime capture devices.
1096 unsigned int max_picture_buffer;
1098 unsigned int nb_chapters;
1099 AVChapter **chapters;
1102 * Flags to enable debugging.
1105 #define FF_FDEBUG_TS 0x0001
1107 #if FF_API_REORDER_PRIVATE
1109 * Raw packets from the demuxer, prior to parsing and decoding.
1110 * This buffer is used for buffering packets until the codec can
1111 * be identified, as parsing cannot be done without knowing the
1114 struct AVPacketList *raw_packet_buffer;
1115 struct AVPacketList *raw_packet_buffer_end;
1117 struct AVPacketList *packet_buffer_end;
1120 AVDictionary *metadata;
1122 #if FF_API_REORDER_PRIVATE
1124 * Remaining size available for raw_packet_buffer, in bytes.
1125 * NOT PART OF PUBLIC API
1127 #define RAW_PACKET_BUFFER_SIZE 2500000
1128 int raw_packet_buffer_remaining_size;
1132 * Start time of the stream in real world time, in microseconds
1133 * since the unix epoch (00:00 1st January 1970). That is, pts=0
1134 * in the stream was captured at this real world time.
1135 * - encoding: Set by user.
1136 * - decoding: Unused.
1138 int64_t start_time_realtime;
1141 * decoding: number of frames used to probe fps
1146 * Error recognition; higher values will detect more errors but may
1147 * misdetect some more or less valid parts as errors.
1148 * - encoding: unused
1149 * - decoding: Set by user.
1151 int error_recognition;
1154 * Custom interrupt callbacks for the I/O layer.
1156 * decoding: set by the user before avformat_open_input().
1157 * encoding: set by the user before avformat_write_header()
1158 * (mainly useful for AVFMT_NOFILE formats). The callback
1159 * should also be passed to avio_open2() if it's used to
1162 AVIOInterruptCB interrupt_callback;
1165 * Transport stream id.
1166 * This will be moved into demuxer private options. Thus no API/ABI compatibility
1171 * Audio preload in microseconds.
1172 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1173 * - encoding: Set by user via AVOptions (NO direct access)
1174 * - decoding: unused
1179 * Max chunk time in microseconds.
1180 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1181 * - encoding: Set by user via AVOptions (NO direct access)
1182 * - decoding: unused
1184 int max_chunk_duration;
1187 * Max chunk size in bytes
1188 * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
1189 * - encoding: Set by user via AVOptions (NO direct access)
1190 * - decoding: unused
1194 /*****************************************************************
1195 * All fields below this line are not part of the public API. They
1196 * may not be used outside of libavformat and can be changed and
1198 * New public fields should be added right above.
1199 *****************************************************************
1201 #if !FF_API_REORDER_PRIVATE
1203 * Raw packets from the demuxer, prior to parsing and decoding.
1204 * This buffer is used for buffering packets until the codec can
1205 * be identified, as parsing cannot be done without knowing the
1208 struct AVPacketList *raw_packet_buffer;
1209 struct AVPacketList *raw_packet_buffer_end;
1211 * Remaining size available for raw_packet_buffer, in bytes.
1213 #define RAW_PACKET_BUFFER_SIZE 2500000
1214 int raw_packet_buffer_remaining_size;
1217 * This buffer is only needed when packets were already buffered but
1218 * not decoded, for example to get the codec parameters in MPEG
1221 struct AVPacketList *packet_buffer;
1222 struct AVPacketList *packet_buffer_end;
1224 /* av_read_frame() support */
1227 /* av_seek_frame() support */
1228 int64_t data_offset; /**< offset of the first packet */
1232 typedef struct AVPacketList {
1234 struct AVPacketList *next;
1239 * @defgroup lavf_core Core functions
1242 * Functions for querying libavformat capabilities, allocating core structures,
1248 * Return the LIBAVFORMAT_VERSION_INT constant.
1250 unsigned avformat_version(void);
1253 * Return the libavformat build-time configuration.
1255 const char *avformat_configuration(void);
1258 * Return the libavformat license.
1260 const char *avformat_license(void);
1263 * Initialize libavformat and register all the muxers, demuxers and
1264 * protocols. If you do not call this function, then you can select
1265 * exactly which formats you want to support.
1267 * @see av_register_input_format()
1268 * @see av_register_output_format()
1269 * @see av_register_protocol()
1271 void av_register_all(void);
1273 void av_register_input_format(AVInputFormat *format);
1274 void av_register_output_format(AVOutputFormat *format);
1277 * Do global initialization of network components. This is optional,
1278 * but recommended, since it avoids the overhead of implicitly
1279 * doing the setup for each session.
1281 * Calling this function will become mandatory if using network
1282 * protocols at some major version bump.
1284 int avformat_network_init(void);
1287 * Undo the initialization done by avformat_network_init.
1289 int avformat_network_deinit(void);
1292 * If f is NULL, returns the first registered input format,
1293 * if f is non-NULL, returns the next registered input format after f
1294 * or NULL if f is the last one.
1296 AVInputFormat *av_iformat_next(AVInputFormat *f);
1299 * If f is NULL, returns the first registered output format,
1300 * if f is non-NULL, returns the next registered output format after f
1301 * or NULL if f is the last one.
1303 AVOutputFormat *av_oformat_next(AVOutputFormat *f);
1306 * Allocate an AVFormatContext.
1307 * avformat_free_context() can be used to free the context and everything
1308 * allocated by the framework within it.
1310 AVFormatContext *avformat_alloc_context(void);
1313 * Free an AVFormatContext and all its streams.
1314 * @param s context to free
1316 void avformat_free_context(AVFormatContext *s);
1319 * Get the AVClass for AVFormatContext. It can be used in combination with
1320 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
1322 * @see av_opt_find().
1324 const AVClass *avformat_get_class(void);
1327 * Add a new stream to a media file.
1329 * When demuxing, it is called by the demuxer in read_header(). If the
1330 * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
1331 * be called in read_packet().
1333 * When muxing, should be called by the user before avformat_write_header().
1335 * @param c If non-NULL, the AVCodecContext corresponding to the new stream
1336 * will be initialized to use this codec. This is needed for e.g. codec-specific
1337 * defaults to be set, so codec should be provided if it is known.
1339 * @return newly created stream or NULL on error.
1341 AVStream *avformat_new_stream(AVFormatContext *s, AVCodec *c);
1343 AVProgram *av_new_program(AVFormatContext *s, int id);
1350 #if FF_API_GUESS_IMG2_CODEC
1351 attribute_deprecated enum CodecID av_guess_image2_codec(const char *filename);
1355 attribute_deprecated void av_pkt_dump(FILE *f, AVPacket *pkt, int dump_payload);
1356 attribute_deprecated void av_pkt_dump_log(void *avcl, int level, AVPacket *pkt,
1361 #if FF_API_ALLOC_OUTPUT_CONTEXT
1363 * @deprecated deprecated in favor of avformat_alloc_output_context2()
1365 attribute_deprecated
1366 AVFormatContext *avformat_alloc_output_context(const char *format,
1367 AVOutputFormat *oformat,
1368 const char *filename);
1372 * Allocate an AVFormatContext for an output format.
1373 * avformat_free_context() can be used to free the context and
1374 * everything allocated by the framework within it.
1376 * @param *ctx is set to the created format context, or to NULL in
1378 * @param oformat format to use for allocating the context, if NULL
1379 * format_name and filename are used instead
1380 * @param format_name the name of output format to use for allocating the
1381 * context, if NULL filename is used instead
1382 * @param filename the name of the filename to use for allocating the
1383 * context, may be NULL
1384 * @return >= 0 in case of success, a negative AVERROR code in case of
1387 int avformat_alloc_output_context2(AVFormatContext **ctx, AVOutputFormat *oformat,
1388 const char *format_name, const char *filename);
1391 * @addtogroup lavf_decoding
1396 * Find AVInputFormat based on the short name of the input format.
1398 AVInputFormat *av_find_input_format(const char *short_name);
1401 * Guess the file format.
1403 * @param is_opened Whether the file is already opened; determines whether
1404 * demuxers with or without AVFMT_NOFILE are probed.
1406 AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
1409 * Guess the file format.
1411 * @param is_opened Whether the file is already opened; determines whether
1412 * demuxers with or without AVFMT_NOFILE are probed.
1413 * @param score_max A probe score larger that this is required to accept a
1414 * detection, the variable is set to the actual detection
1416 * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
1417 * to retry with a larger probe buffer.
1419 AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max);
1422 * Guess the file format.
1424 * @param is_opened Whether the file is already opened; determines whether
1425 * demuxers with or without AVFMT_NOFILE are probed.
1426 * @param score_ret The score of the best detection.
1428 AVInputFormat *av_probe_input_format3(AVProbeData *pd, int is_opened, int *score_ret);
1431 * Probe a bytestream to determine the input format. Each time a probe returns
1432 * with a score that is too low, the probe buffer size is increased and another
1433 * attempt is made. When the maximum probe size is reached, the input format
1434 * with the highest score is returned.
1436 * @param pb the bytestream to probe
1437 * @param fmt the input format is put here
1438 * @param filename the filename of the stream
1439 * @param logctx the log context
1440 * @param offset the offset within the bytestream to probe from
1441 * @param max_probe_size the maximum probe buffer size (zero for default)
1442 * @return 0 in case of success, a negative value corresponding to an
1443 * AVERROR code otherwise
1445 int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt,
1446 const char *filename, void *logctx,
1447 unsigned int offset, unsigned int max_probe_size);
1449 #if FF_API_FORMAT_PARAMETERS
1451 * Allocate all the structures needed to read an input stream.
1452 * This does not open the needed codecs for decoding the stream[s].
1453 * @deprecated use avformat_open_input instead.
1455 attribute_deprecated int av_open_input_stream(AVFormatContext **ic_ptr,
1456 AVIOContext *pb, const char *filename,
1457 AVInputFormat *fmt, AVFormatParameters *ap);
1460 * Open a media file as input. The codecs are not opened. Only the file
1461 * header (if present) is read.
1463 * @param ic_ptr The opened media file handle is put here.
1464 * @param filename filename to open
1465 * @param fmt If non-NULL, force the file format to use.
1466 * @param buf_size optional buffer size (zero if default is OK)
1467 * @param ap Additional parameters needed when opening the file
1468 * (NULL if default).
1469 * @return 0 if OK, AVERROR_xxx otherwise
1471 * @deprecated use avformat_open_input instead.
1473 attribute_deprecated int av_open_input_file(AVFormatContext **ic_ptr, const char *filename,
1476 AVFormatParameters *ap);
1480 * Open an input stream and read the header. The codecs are not opened.
1481 * The stream must be closed with av_close_input_file().
1483 * @param ps Pointer to user-supplied AVFormatContext (allocated by avformat_alloc_context).
1484 * May be a pointer to NULL, in which case an AVFormatContext is allocated by this
1485 * function and written into ps.
1486 * Note that a user-supplied AVFormatContext will be freed on failure.
1487 * @param filename Name of the stream to open.
1488 * @param fmt If non-NULL, this parameter forces a specific input format.
1489 * Otherwise the format is autodetected.
1490 * @param options A dictionary filled with AVFormatContext and demuxer-private options.
1491 * On return this parameter will be destroyed and replaced with a dict containing
1492 * options that were not found. May be NULL.
1494 * @return 0 on success, a negative AVERROR on failure.
1496 * @note If you want to use custom IO, preallocate the format context and set its pb field.
1498 int avformat_open_input(AVFormatContext **ps, const char *filename, AVInputFormat *fmt, AVDictionary **options);
1500 int av_demuxer_open(AVFormatContext *ic, AVFormatParameters *ap);
1502 #if FF_API_FORMAT_PARAMETERS
1504 * Read packets of a media file to get stream information. This
1505 * is useful for file formats with no headers such as MPEG. This
1506 * function also computes the real framerate in case of MPEG-2 repeat
1508 * The logical file position is not changed by this function;
1509 * examined packets may be buffered for later processing.
1511 * @param ic media file handle
1512 * @return >=0 if OK, AVERROR_xxx on error
1513 * @todo Let the user decide somehow what information is needed so that
1514 * we do not waste time getting stuff the user does not need.
1516 * @deprecated use avformat_find_stream_info.
1518 attribute_deprecated
1519 int av_find_stream_info(AVFormatContext *ic);
1523 * Read packets of a media file to get stream information. This
1524 * is useful for file formats with no headers such as MPEG. This
1525 * function also computes the real framerate in case of MPEG-2 repeat
1527 * The logical file position is not changed by this function;
1528 * examined packets may be buffered for later processing.
1530 * @param ic media file handle
1531 * @param options If non-NULL, an ic.nb_streams long array of pointers to
1532 * dictionaries, where i-th member contains options for
1533 * codec corresponding to i-th stream.
1534 * On return each dictionary will be filled with options that were not found.
1535 * @return >=0 if OK, AVERROR_xxx on error
1537 * @note this function isn't guaranteed to open all the codecs, so
1538 * options being non-empty at return is a perfectly normal behavior.
1540 * @todo Let the user decide somehow what information is needed so that
1541 * we do not waste time getting stuff the user does not need.
1543 int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options);
1546 * Find the programs which belong to a given stream.
1548 * @param ic media file handle
1549 * @param last the last found program, the search will start after this
1550 * program, or from the beginning if it is NULL
1551 * @param s stream index
1552 * @return the next program which belongs to s, NULL if no program is found or
1553 * the last program is not among the programs of ic.
1555 AVProgram *av_find_program_from_stream(AVFormatContext *ic, AVProgram *last, int s);
1558 * Find the "best" stream in the file.
1559 * The best stream is determined according to various heuristics as the most
1560 * likely to be what the user expects.
1561 * If the decoder parameter is non-NULL, av_find_best_stream will find the
1562 * default decoder for the stream's codec; streams for which no decoder can
1563 * be found are ignored.
1565 * @param ic media file handle
1566 * @param type stream type: video, audio, subtitles, etc.
1567 * @param wanted_stream_nb user-requested stream number,
1568 * or -1 for automatic selection
1569 * @param related_stream try to find a stream related (eg. in the same
1570 * program) to this one, or -1 if none
1571 * @param decoder_ret if non-NULL, returns the decoder for the
1573 * @param flags flags; none are currently defined
1574 * @return the non-negative stream number in case of success,
1575 * AVERROR_STREAM_NOT_FOUND if no stream with the requested type
1577 * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
1578 * @note If av_find_best_stream returns successfully and decoder_ret is not
1579 * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
1581 int av_find_best_stream(AVFormatContext *ic,
1582 enum AVMediaType type,
1583 int wanted_stream_nb,
1585 AVCodec **decoder_ret,
1589 * Read a transport packet from a media file.
1591 * This function is obsolete and should never be used.
1592 * Use av_read_frame() instead.
1594 * @param s media file handle
1595 * @param pkt is filled
1596 * @return 0 if OK, AVERROR_xxx on error
1598 int av_read_packet(AVFormatContext *s, AVPacket *pkt);
1601 * Return the next frame of a stream.
1602 * This function returns what is stored in the file, and does not validate
1603 * that what is there are valid frames for the decoder. It will split what is
1604 * stored in the file into frames and return one for each call. It will not
1605 * omit invalid data between valid frames so as to give the decoder the maximum
1606 * information possible for decoding.
1608 * The returned packet is valid
1609 * until the next av_read_frame() or until av_close_input_file() and
1610 * must be freed with av_free_packet. For video, the packet contains
1611 * exactly one frame. For audio, it contains an integer number of
1612 * frames if each frame has a known fixed size (e.g. PCM or ADPCM
1613 * data). If the audio frames have a variable size (e.g. MPEG audio),
1614 * then it contains one frame.
1616 * pkt->pts, pkt->dts and pkt->duration are always set to correct
1617 * values in AVStream.time_base units (and guessed if the format cannot
1618 * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
1619 * has B-frames, so it is better to rely on pkt->dts if you do not
1620 * decompress the payload.
1622 * @return 0 if OK, < 0 on error or end of file
1624 int av_read_frame(AVFormatContext *s, AVPacket *pkt);
1627 * Seek to the keyframe at timestamp.
1628 * 'timestamp' in 'stream_index'.
1629 * @param stream_index If stream_index is (-1), a default
1630 * stream is selected, and timestamp is automatically converted
1631 * from AV_TIME_BASE units to the stream specific time_base.
1632 * @param timestamp Timestamp in AVStream.time_base units
1633 * or, if no stream is specified, in AV_TIME_BASE units.
1634 * @param flags flags which select direction and seeking mode
1635 * @return >= 0 on success
1637 int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
1641 * Seek to timestamp ts.
1642 * Seeking will be done so that the point from which all active streams
1643 * can be presented successfully will be closest to ts and within min/max_ts.
1644 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
1646 * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
1647 * are the file position (this may not be supported by all demuxers).
1648 * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
1649 * in the stream with stream_index (this may not be supported by all demuxers).
1650 * Otherwise all timestamps are in units of the stream selected by stream_index
1651 * or if stream_index is -1, in AV_TIME_BASE units.
1652 * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
1653 * keyframes (this may not be supported by all demuxers).
1655 * @param stream_index index of the stream which is used as time base reference
1656 * @param min_ts smallest acceptable timestamp
1657 * @param ts target timestamp
1658 * @param max_ts largest acceptable timestamp
1659 * @param flags flags
1660 * @return >=0 on success, error code otherwise
1662 * @note This is part of the new seek API which is still under construction.
1663 * Thus do not use this yet. It may change at any time, do not expect
1664 * ABI compatibility yet!
1666 int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
1669 * Start playing a network-based stream (e.g. RTSP stream) at the
1672 int av_read_play(AVFormatContext *s);
1675 * Pause a network-based stream (e.g. RTSP stream).
1677 * Use av_read_play() to resume it.
1679 int av_read_pause(AVFormatContext *s);
1681 #if FF_API_FORMAT_PARAMETERS
1683 * Free a AVFormatContext allocated by av_open_input_stream.
1684 * @param s context to free
1685 * @deprecated use av_close_input_file()
1687 attribute_deprecated
1688 void av_close_input_stream(AVFormatContext *s);
1691 #if FF_API_CLOSE_INPUT_FILE
1693 * @deprecated use avformat_close_input()
1694 * Close a media file (but not its codecs).
1696 * @param s media file handle
1698 attribute_deprecated
1699 void av_close_input_file(AVFormatContext *s);
1703 * Close an opened input AVFormatContext. Free it and all its contents
1704 * and set *s to NULL.
1706 void avformat_close_input(AVFormatContext **s);
1711 #if FF_API_NEW_STREAM
1713 * Add a new stream to a media file.
1715 * Can only be called in the read_header() function. If the flag
1716 * AVFMTCTX_NOHEADER is in the format context, then new streams
1717 * can be added in read_packet too.
1719 * @param s media file handle
1720 * @param id file-format-dependent stream ID
1722 attribute_deprecated
1723 AVStream *av_new_stream(AVFormatContext *s, int id);
1726 #if FF_API_SET_PTS_INFO
1728 * @deprecated this function is not supposed to be called outside of lavf
1730 attribute_deprecated
1731 void av_set_pts_info(AVStream *s, int pts_wrap_bits,
1732 unsigned int pts_num, unsigned int pts_den);
1735 #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
1736 #define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
1737 #define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
1738 #define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
1740 #if FF_API_SEEK_PUBLIC
1741 attribute_deprecated
1742 int av_seek_frame_binary(AVFormatContext *s, int stream_index,
1743 int64_t target_ts, int flags);
1744 attribute_deprecated
1745 void av_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp);
1746 attribute_deprecated
1747 int64_t av_gen_search(AVFormatContext *s, int stream_index,
1748 int64_t target_ts, int64_t pos_min,
1749 int64_t pos_max, int64_t pos_limit,
1750 int64_t ts_min, int64_t ts_max,
1751 int flags, int64_t *ts_ret,
1752 int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
1755 #if FF_API_FORMAT_PARAMETERS
1757 * @deprecated pass the options to avformat_write_header directly.
1759 attribute_deprecated int av_set_parameters(AVFormatContext *s, AVFormatParameters *ap);
1763 * @addtogroup lavf_encoding
1767 * Allocate the stream private data and write the stream header to
1768 * an output media file.
1770 * @param s Media file handle, must be allocated with avformat_alloc_context().
1771 * Its oformat field must be set to the desired output format;
1772 * Its pb field must be set to an already openened AVIOContext.
1773 * @param options An AVDictionary filled with AVFormatContext and muxer-private options.
1774 * On return this parameter will be destroyed and replaced with a dict containing
1775 * options that were not found. May be NULL.
1777 * @return 0 on success, negative AVERROR on failure.
1779 * @see av_opt_find, av_dict_set, avio_open, av_oformat_next.
1781 int avformat_write_header(AVFormatContext *s, AVDictionary **options);
1783 #if FF_API_FORMAT_PARAMETERS
1785 * Allocate the stream private data and write the stream header to an
1786 * output media file.
1787 * @note: this sets stream time-bases, if possible to stream->codec->time_base
1788 * but for some formats it might also be some other time base
1790 * @param s media file handle
1791 * @return 0 if OK, AVERROR_xxx on error
1793 * @deprecated use avformat_write_header.
1795 attribute_deprecated int av_write_header(AVFormatContext *s);
1799 * Write a packet to an output media file.
1801 * The packet shall contain one audio or video frame.
1802 * The packet must be correctly interleaved according to the container
1803 * specification, if not then av_interleaved_write_frame must be used.
1805 * @param s media file handle
1806 * @param pkt The packet, which contains the stream_index, buf/buf_size,
1808 * @return < 0 on error, = 0 if OK, 1 if end of stream wanted
1810 int av_write_frame(AVFormatContext *s, AVPacket *pkt);
1813 * Write a packet to an output media file ensuring correct interleaving.
1815 * The packet must contain one audio or video frame.
1816 * If the packets are already correctly interleaved, the application should
1817 * call av_write_frame() instead as it is slightly faster. It is also important
1818 * to keep in mind that completely non-interleaved input will need huge amounts
1819 * of memory to interleave with this, so it is preferable to interleave at the
1822 * @param s media file handle
1823 * @param pkt The packet, which contains the stream_index, buf/buf_size,
1825 * @return < 0 on error, = 0 if OK, 1 if end of stream wanted
1827 int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
1830 * Interleave a packet per dts in an output media file.
1832 * Packets with pkt->destruct == av_destruct_packet will be freed inside this
1833 * function, so they cannot be used after it. Note that calling av_free_packet()
1834 * on them is still safe.
1836 * @param s media file handle
1837 * @param out the interleaved packet will be output here
1838 * @param pkt the input packet
1839 * @param flush 1 if no further packets are available as input and all
1840 * remaining packets should be output
1841 * @return 1 if a packet was output, 0 if no packet could be output,
1842 * < 0 if an error occurred
1844 int av_interleave_packet_per_dts(AVFormatContext *s, AVPacket *out,
1845 AVPacket *pkt, int flush);
1848 * Write the stream trailer to an output media file and free the
1849 * file private data.
1851 * May only be called after a successful call to av_write_header.
1853 * @param s media file handle
1854 * @return 0 if OK, AVERROR_xxx on error
1856 int av_write_trailer(AVFormatContext *s);
1859 * Return the output format in the list of registered output formats
1860 * which best matches the provided parameters, or return NULL if
1861 * there is no match.
1863 * @param short_name if non-NULL checks if short_name matches with the
1864 * names of the registered formats
1865 * @param filename if non-NULL checks if filename terminates with the
1866 * extensions of the registered formats
1867 * @param mime_type if non-NULL checks if mime_type matches with the
1868 * MIME type of the registered formats
1870 AVOutputFormat *av_guess_format(const char *short_name,
1871 const char *filename,
1872 const char *mime_type);
1875 * Guess the codec ID based upon muxer and filename.
1877 enum CodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
1878 const char *filename, const char *mime_type,
1879 enum AVMediaType type);
1882 * Get timing information for the data currently output.
1883 * The exact meaning of "currently output" depends on the format.
1884 * It is mostly relevant for devices that have an internal buffer and/or
1885 * work in real time.
1886 * @param s media file handle
1887 * @param stream stream in the media file
1888 * @param dts[out] DTS of the last packet output for the stream, in stream
1890 * @param wall[out] absolute time when that packet whas output,
1892 * @return 0 if OK, AVERROR(ENOSYS) if the format does not support it
1893 * Note: some formats or devices may not allow to measure dts and wall
1896 int av_get_output_timestamp(struct AVFormatContext *s, int stream,
1897 int64_t *dts, int64_t *wall);
1906 * @defgroup lavf_misc Utility functions
1910 * Miscelaneous utility functions related to both muxing and demuxing
1915 * Send a nice hexadecimal dump of a buffer to the specified file stream.
1917 * @param f The file stream pointer where the dump should be sent to.
1919 * @param size buffer size
1921 * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2
1923 void av_hex_dump(FILE *f, uint8_t *buf, int size);
1926 * Send a nice hexadecimal dump of a buffer to the log.
1928 * @param avcl A pointer to an arbitrary struct of which the first field is a
1929 * pointer to an AVClass struct.
1930 * @param level The importance level of the message, lower values signifying
1931 * higher importance.
1933 * @param size buffer size
1935 * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2
1937 void av_hex_dump_log(void *avcl, int level, uint8_t *buf, int size);
1940 * Send a nice dump of a packet to the specified file stream.
1942 * @param f The file stream pointer where the dump should be sent to.
1943 * @param pkt packet to dump
1944 * @param dump_payload True if the payload must be displayed, too.
1945 * @param st AVStream that the packet belongs to
1947 void av_pkt_dump2(FILE *f, AVPacket *pkt, int dump_payload, AVStream *st);
1951 * Send a nice dump of a packet to the log.
1953 * @param avcl A pointer to an arbitrary struct of which the first field is a
1954 * pointer to an AVClass struct.
1955 * @param level The importance level of the message, lower values signifying
1956 * higher importance.
1957 * @param pkt packet to dump
1958 * @param dump_payload True if the payload must be displayed, too.
1959 * @param st AVStream that the packet belongs to
1961 void av_pkt_dump_log2(void *avcl, int level, AVPacket *pkt, int dump_payload,
1965 * Get the CodecID for the given codec tag tag.
1966 * If no codec id is found returns CODEC_ID_NONE.
1968 * @param tags list of supported codec_id-codec_tag pairs, as stored
1969 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
1971 enum CodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
1974 * Get the codec tag for the given codec id id.
1975 * If no codec tag is found returns 0.
1977 * @param tags list of supported codec_id-codec_tag pairs, as stored
1978 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
1980 unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum CodecID id);
1982 int av_find_default_stream_index(AVFormatContext *s);
1985 * Get the index for a specific timestamp.
1986 * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
1987 * to the timestamp which is <= the requested one, if backward
1988 * is 0, then it will be >=
1989 * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
1990 * @return < 0 if no such timestamp could be found
1992 int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
1995 * Add an index entry into a sorted list. Update the entry if the list
1996 * already contains it.
1998 * @param timestamp timestamp in the time base of the given stream
2000 int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
2001 int size, int distance, int flags);
2005 * Split a URL string into components.
2007 * The pointers to buffers for storing individual components may be null,
2008 * in order to ignore that component. Buffers for components not found are
2009 * set to empty strings. If the port is not found, it is set to a negative
2012 * @param proto the buffer for the protocol
2013 * @param proto_size the size of the proto buffer
2014 * @param authorization the buffer for the authorization
2015 * @param authorization_size the size of the authorization buffer
2016 * @param hostname the buffer for the host name
2017 * @param hostname_size the size of the hostname buffer
2018 * @param port_ptr a pointer to store the port number in
2019 * @param path the buffer for the path
2020 * @param path_size the size of the path buffer
2021 * @param url the URL to split
2023 void av_url_split(char *proto, int proto_size,
2024 char *authorization, int authorization_size,
2025 char *hostname, int hostname_size,
2027 char *path, int path_size,
2030 #if FF_API_DUMP_FORMAT
2032 * @deprecated Deprecated in favor of av_dump_format().
2034 attribute_deprecated void dump_format(AVFormatContext *ic,
2040 void av_dump_format(AVFormatContext *ic,
2045 #if FF_API_PARSE_DATE
2047 * Parse datestr and return a corresponding number of microseconds.
2049 * @param datestr String representing a date or a duration.
2050 * See av_parse_time() for the syntax of the provided string.
2051 * @deprecated in favor of av_parse_time()
2053 attribute_deprecated
2054 int64_t parse_date(const char *datestr, int duration);
2058 * Get the current time in microseconds.
2060 int64_t av_gettime(void);
2062 #if FF_API_FIND_INFO_TAG
2064 * @deprecated use av_find_info_tag in libavutil instead.
2066 attribute_deprecated int find_info_tag(char *arg, int arg_size, const char *tag1, const char *info);
2070 * Return in 'buf' the path with '%d' replaced by a number.
2072 * Also handles the '%0nd' format where 'n' is the total number
2073 * of digits and '%%'.
2075 * @param buf destination buffer
2076 * @param buf_size destination buffer size
2077 * @param path numbered sequence string
2078 * @param number frame number
2079 * @return 0 if OK, -1 on format error
2081 int av_get_frame_filename(char *buf, int buf_size,
2082 const char *path, int number);
2085 * Check whether filename actually is a numbered sequence generator.
2087 * @param filename possible numbered sequence string
2088 * @return 1 if a valid numbered sequence string, 0 otherwise
2090 int av_filename_number_test(const char *filename);
2093 * Generate an SDP for an RTP session.
2095 * @param ac array of AVFormatContexts describing the RTP streams. If the
2096 * array is composed by only one context, such context can contain
2097 * multiple AVStreams (one AVStream per RTP stream). Otherwise,
2098 * all the contexts in the array (an AVCodecContext per RTP stream)
2099 * must contain only one AVStream.
2100 * @param n_files number of AVCodecContexts contained in ac
2101 * @param buf buffer where the SDP will be stored (must be allocated by
2103 * @param size the size of the buffer
2104 * @return 0 if OK, AVERROR_xxx on error
2106 int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size);
2108 #if FF_API_SDP_CREATE
2109 attribute_deprecated int avf_sdp_create(AVFormatContext *ac[], int n_files, char *buff, int size);
2113 * Return a positive value if the given filename has one of the given
2114 * extensions, 0 otherwise.
2116 * @param extensions a comma-separated list of filename extensions
2118 int av_match_ext(const char *filename, const char *extensions);
2121 * Test if the given container can store a codec.
2123 * @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
2125 * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
2126 * A negative number if this information is not available.
2128 int avformat_query_codec(AVOutputFormat *ofmt, enum CodecID codec_id, int std_compliance);
2134 #endif /* AVFORMAT_AVFORMAT_H */