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
24 #define LIBAVFORMAT_VERSION_MAJOR 52
25 #define LIBAVFORMAT_VERSION_MINOR 80
26 #define LIBAVFORMAT_VERSION_MICRO 0
28 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
29 LIBAVFORMAT_VERSION_MINOR, \
30 LIBAVFORMAT_VERSION_MICRO)
31 #define LIBAVFORMAT_VERSION AV_VERSION(LIBAVFORMAT_VERSION_MAJOR, \
32 LIBAVFORMAT_VERSION_MINOR, \
33 LIBAVFORMAT_VERSION_MICRO)
34 #define LIBAVFORMAT_BUILD LIBAVFORMAT_VERSION_INT
36 #define LIBAVFORMAT_IDENT "Lavf" AV_STRINGIFY(LIBAVFORMAT_VERSION)
39 * Those FF_API_* defines are not part of public API.
40 * They may change, break or disappear at any time.
42 #ifndef FF_API_MAX_STREAMS
43 #define FF_API_MAX_STREAMS (LIBAVFORMAT_VERSION_MAJOR < 53)
45 #ifndef FF_API_OLD_METADATA
46 #define FF_API_OLD_METADATA (LIBAVFORMAT_VERSION_MAJOR < 53)
48 #ifndef FF_API_URL_CLASS
49 #define FF_API_URL_CLASS (LIBAVFORMAT_VERSION_MAJOR >= 53)
51 #ifndef FF_API_URL_RESETBUF
52 #define FF_API_URL_RESETBUF (LIBAVFORMAT_VERSION_MAJOR < 53)
54 #ifndef FF_API_REGISTER_PROTOCOL
55 #define FF_API_REGISTER_PROTOCOL (LIBAVFORMAT_VERSION_MAJOR < 53)
59 * I return the LIBAVFORMAT_VERSION_INT constant. You got
60 * a fucking problem with that, douchebag?
62 unsigned avformat_version(void);
65 * Return the libavformat build-time configuration.
67 const char *avformat_configuration(void);
70 * Return the libavformat license.
72 const char *avformat_license(void);
75 #include <stdio.h> /* FILE */
76 #include "libavcodec/avcodec.h"
80 struct AVFormatContext;
84 * Public Metadata API.
85 * The metadata API allows libavformat to export metadata tags to a client
86 * application using a sequence of key/value pairs. Like all strings in FFmpeg,
87 * metadata must be stored as UTF-8 encoded Unicode. Note that metadata
88 * exported by demuxers isn't checked to be valid UTF-8 in most cases.
89 * Important concepts to keep in mind:
90 * 1. Keys are unique; there can never be 2 tags with the same key. This is
91 * also meant semantically, i.e., a demuxer should not knowingly produce
92 * several keys that are literally different but semantically identical.
93 * E.g., key=Author5, key=Author6. In this example, all authors must be
94 * placed in the same tag.
95 * 2. Metadata is flat, not hierarchical; there are no subtags. If you
96 * want to store, e.g., the email address of the child of producer Alice
97 * and actor Bob, that could have key=alice_and_bobs_childs_email_address.
98 * 3. Several modifiers can be applied to the tag name. This is done by
99 * appending a dash character ('-') and the modifier name in the order
100 * they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng.
101 * a) language -- a tag whose value is localized for a particular language
102 * is appended with the ISO 639-2/B 3-letter language code.
103 * For example: Author-ger=Michael, Author-eng=Mike
104 * The original/default language is in the unqualified "Author" tag.
105 * A demuxer should set a default if it sets any translated tag.
106 * b) sorting -- a modified version of a tag that should be used for
107 * sorting will have '-sort' appended. E.g. artist="The Beatles",
108 * artist-sort="Beatles, The".
110 * 4. Tag names are normally exported exactly as stored in the container to
111 * allow lossless remuxing to the same format. For container-independent
112 * handling of metadata, av_metadata_conv() can convert it to ffmpeg generic
113 * format. Follows a list of generic tag names:
115 * album -- name of the set this work belongs to
116 * album_artist -- main creator of the set/album, if different from artist.
117 * e.g. "Various Artists" for compilation albums.
118 * artist -- main creator of the work
119 * comment -- any additional description of the file.
120 * composer -- who composed the work, if different from artist.
121 * copyright -- name of copyright holder.
122 * date -- date when the work was created, preferably in ISO 8601.
123 * disc -- number of a subset, e.g. disc in a multi-disc collection.
124 * encoder -- name/settings of the software/hardware that produced the file.
125 * encoded_by -- person/group who created the file.
126 * filename -- original name of the file.
127 * genre -- <self-evident>.
128 * language -- main language in which the work is performed, preferably
129 * in ISO 639-2 format.
130 * performer -- artist who performed the work, if different from artist.
131 * E.g for "Also sprach Zarathustra", artist would be "Richard
132 * Strauss" and performer "London Philharmonic Orchestra".
133 * publisher -- name of the label/publisher.
134 * title -- name of the work.
135 * track -- number of this work in the set, can be in form current/total.
138 #define AV_METADATA_MATCH_CASE 1
139 #define AV_METADATA_IGNORE_SUFFIX 2
140 #define AV_METADATA_DONT_STRDUP_KEY 4
141 #define AV_METADATA_DONT_STRDUP_VAL 8
142 #define AV_METADATA_DONT_OVERWRITE 16 ///< Don't overwrite existing tags.
149 typedef struct AVMetadata AVMetadata;
150 typedef struct AVMetadataConv AVMetadataConv;
153 * Get a metadata element with matching key.
155 * @param prev Set to the previous matching element to find the next.
156 * If set to NULL the first matching element is returned.
157 * @param flags Allows case as well as suffix-insensitive comparisons.
158 * @return Found tag or NULL, changing key or value leads to undefined behavior.
161 av_metadata_get(AVMetadata *m, const char *key, const AVMetadataTag *prev, int flags);
163 #if FF_API_OLD_METADATA
165 * Set the given tag in *pm, overwriting an existing tag.
167 * @param pm pointer to a pointer to a metadata struct. If *pm is NULL
168 * a metadata struct is allocated and put in *pm.
169 * @param key tag key to add to *pm (will be av_strduped)
170 * @param value tag value to add to *pm (will be av_strduped)
171 * @return >= 0 on success otherwise an error code <0
172 * @deprecated Use av_metadata_set2() instead.
174 attribute_deprecated int av_metadata_set(AVMetadata **pm, const char *key, const char *value);
178 * Set the given tag in *pm, overwriting an existing tag.
180 * @param pm pointer to a pointer to a metadata struct. If *pm is NULL
181 * a metadata struct is allocated and put in *pm.
182 * @param key tag key to add to *pm (will be av_strduped depending on flags)
183 * @param value tag value to add to *pm (will be av_strduped depending on flags).
184 * Passing a NULL value will cause an existing tag to be deleted.
185 * @return >= 0 on success otherwise an error code <0
187 int av_metadata_set2(AVMetadata **pm, const char *key, const char *value, int flags);
190 * Convert all the metadata sets from ctx according to the source and
191 * destination conversion tables. If one of the tables is NULL, then
192 * tags are converted to/from ffmpeg generic tag names.
194 * @param d_conv destination tags format conversion table
195 * @param s_conv source tags format conversion table
197 void av_metadata_conv(struct AVFormatContext *ctx, const AVMetadataConv *d_conv,
198 const AVMetadataConv *s_conv);
201 * Free all the memory allocated for an AVMetadata struct.
203 void av_metadata_free(AVMetadata **m);
206 /* packet functions */
210 * Allocate and read the payload of a packet and initialize its
211 * fields with default values.
214 * @param size desired payload size
215 * @return >0 (read size) if OK, AVERROR_xxx otherwise
217 int av_get_packet(ByteIOContext *s, AVPacket *pkt, int size);
220 /*************************************************/
221 /* fractional numbers for exact pts handling */
224 * The exact value of the fractional number is: 'val + num / den'.
225 * num is assumed to be 0 <= num < den.
227 typedef struct AVFrac {
228 int64_t val, num, den;
231 /*************************************************/
232 /* input/output formats */
237 * This structure contains the data a format has to probe a file.
239 typedef struct AVProbeData {
240 const char *filename;
241 unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
242 int buf_size; /**< Size of buf except extra allocated bytes */
245 #define AVPROBE_SCORE_MAX 100 ///< maximum score, half of that is used for file-extension-based detection
246 #define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
248 typedef struct AVFormatParameters {
249 AVRational time_base;
254 enum PixelFormat pix_fmt;
255 int channel; /**< Used to select DV channel. */
256 const char *standard; /**< TV standard, NTSC, PAL, SECAM */
257 unsigned int mpeg2ts_raw:1; /**< Force raw MPEG-2 transport stream output, if possible. */
258 unsigned int mpeg2ts_compute_pcr:1; /**< Compute exact PCR for each transport
259 stream packet (only meaningful if
260 mpeg2ts_raw is TRUE). */
261 unsigned int initial_pause:1; /**< Do not begin to play the stream
262 immediately (RTSP only). */
263 unsigned int prealloced_context:1;
264 #if LIBAVFORMAT_VERSION_INT < (53<<16)
265 enum CodecID video_codec_id;
266 enum CodecID audio_codec_id;
268 } AVFormatParameters;
270 //! Demuxer will use url_fopen, no opened file should be provided by the caller.
271 #define AVFMT_NOFILE 0x0001
272 #define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
273 #define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
274 #define AVFMT_RAWPICTURE 0x0020 /**< Format wants AVPicture structure for
276 #define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
277 #define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
278 #define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
279 #define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. */
280 #define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */
281 #define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */
283 typedef struct AVOutputFormat {
286 * Descriptive name for the format, meant to be more human-readable
287 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
290 const char *long_name;
291 const char *mime_type;
292 const char *extensions; /**< comma-separated filename extensions */
294 * size of private data so that it can be allocated in the wrapper
298 enum CodecID audio_codec; /**< default audio codec */
299 enum CodecID video_codec; /**< default video codec */
300 int (*write_header)(struct AVFormatContext *);
301 int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
302 int (*write_trailer)(struct AVFormatContext *);
304 * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_GLOBALHEADER
308 * Currently only used to set pixel format if not YUV420P.
310 int (*set_parameters)(struct AVFormatContext *, AVFormatParameters *);
311 int (*interleave_packet)(struct AVFormatContext *, AVPacket *out,
312 AVPacket *in, int flush);
315 * List of supported codec_id-codec_tag pairs, ordered by "better
316 * choice first". The arrays are all terminated by CODEC_ID_NONE.
318 const struct AVCodecTag * const *codec_tag;
320 enum CodecID subtitle_codec; /**< default subtitle codec */
322 const AVMetadataConv *metadata_conv;
325 struct AVOutputFormat *next;
328 typedef struct AVInputFormat {
330 * A comma separated list of short names for the format. New names
331 * may be appended with a minor bump.
336 * Descriptive name for the format, meant to be more human-readable
337 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
340 const char *long_name;
343 * Size of private data so that it can be allocated in the wrapper.
348 * Tell if a given file has a chance of being parsed as this format.
349 * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
350 * big so you do not have to check for that unless you need more.
352 int (*read_probe)(AVProbeData *);
355 * Read the format header and initialize the AVFormatContext
356 * structure. Return 0 if OK. 'ap' if non-NULL contains
357 * additional parameters. Only used in raw format right
358 * now. 'av_new_stream' should be called to create new streams.
360 int (*read_header)(struct AVFormatContext *,
361 AVFormatParameters *ap);
364 * Read one packet and put it in 'pkt'. pts and flags are also
365 * set. 'av_new_stream' can be called only if the flag
366 * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
367 * background thread).
368 * @return 0 on success, < 0 on error.
369 * When returning an error, pkt must not have been allocated
370 * or must be freed before returning
372 int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
375 * Close the stream. The AVFormatContext and AVStreams are not
376 * freed by this function
378 int (*read_close)(struct AVFormatContext *);
380 #if LIBAVFORMAT_VERSION_MAJOR < 53
382 * Seek to a given timestamp relative to the frames in
383 * stream component stream_index.
384 * @param stream_index Must not be -1.
385 * @param flags Selects which direction should be preferred if no exact
386 * match is available.
387 * @return >= 0 on success (but not necessarily the new offset)
389 int (*read_seek)(struct AVFormatContext *,
390 int stream_index, int64_t timestamp, int flags);
393 * Gets the next timestamp in stream[stream_index].time_base units.
394 * @return the timestamp or AV_NOPTS_VALUE if an error occurred
396 int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
397 int64_t *pos, int64_t pos_limit);
400 * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER.
405 * If extensions are defined, then no probe is done. You should
406 * usually not use extension format guessing because it is not
409 const char *extensions;
412 * General purpose read-only value that the format can use.
417 * Start/resume playing - only meaningful if using a network-based format
420 int (*read_play)(struct AVFormatContext *);
423 * Pause playing - only meaningful if using a network-based format
426 int (*read_pause)(struct AVFormatContext *);
428 const struct AVCodecTag * const *codec_tag;
431 * Seek to timestamp ts.
432 * Seeking will be done so that the point from which all active streams
433 * can be presented successfully will be closest to ts and within min/max_ts.
434 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
436 int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
438 const AVMetadataConv *metadata_conv;
441 struct AVInputFormat *next;
444 enum AVStreamParseType {
446 AVSTREAM_PARSE_FULL, /**< full parsing and repack */
447 AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
448 AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
449 AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
452 typedef struct AVIndexEntry {
455 #define AVINDEX_KEYFRAME 0x0001
457 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).
458 int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
461 #define AV_DISPOSITION_DEFAULT 0x0001
462 #define AV_DISPOSITION_DUB 0x0002
463 #define AV_DISPOSITION_ORIGINAL 0x0004
464 #define AV_DISPOSITION_COMMENT 0x0008
465 #define AV_DISPOSITION_LYRICS 0x0010
466 #define AV_DISPOSITION_KARAOKE 0x0020
469 * Track should be used during playback by default.
470 * Useful for subtitle track that should be displayed
471 * even when user did not explicitly ask for subtitles.
473 #define AV_DISPOSITION_FORCED 0x0040
477 * New fields can be added to the end with minor version bumps.
478 * Removal, reordering and changes to existing fields require a major
480 * sizeof(AVStream) must not be used outside libav*.
482 typedef struct AVStream {
483 int index; /**< stream index in AVFormatContext */
484 int id; /**< format-specific stream ID */
485 AVCodecContext *codec; /**< codec context */
487 * Real base framerate of the stream.
488 * This is the lowest framerate with which all timestamps can be
489 * represented accurately (it is the least common multiple of all
490 * framerates in the stream). Note, this value is just a guess!
491 * For example, if the time base is 1/90000 and all frames have either
492 * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
494 AVRational r_frame_rate;
497 /* internal data used in av_find_stream_info() */
501 * encoding: pts generation when outputting stream
506 * This is the fundamental unit of time (in seconds) in terms
507 * of which frame timestamps are represented. For fixed-fps content,
508 * time base should be 1/framerate and timestamp increments should be 1.
510 AVRational time_base;
511 int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
512 /* ffmpeg.c private use */
513 int stream_copy; /**< If set, just copy stream. */
514 enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
516 //FIXME move stuff to a flags field?
518 * Quality, as it has been removed from AVCodecContext and put in AVVideoFrame.
519 * MN: dunno if that is the right place for it
524 * Decoding: pts of the first frame of the stream, in stream time base.
525 * Only set this if you are absolutely 100% sure that the value you set
526 * it to really is the pts of the first frame.
527 * This may be undefined (AV_NOPTS_VALUE).
528 * @note The ASF header does NOT contain a correct start_time the ASF
529 * demuxer must NOT set this.
534 * Decoding: duration of the stream, in stream time base.
535 * If a source file does not specify a duration, but does specify
536 * a bitrate, this value will be estimated from bitrate and file size.
540 #if FF_API_OLD_METADATA
541 char language[4]; /**< ISO 639-2/B 3-letter language code (empty string if undefined) */
544 /* av_read_frame() support */
545 enum AVStreamParseType need_parsing;
546 struct AVCodecParserContext *parser;
549 int last_IP_duration;
551 /* av_seek_frame() support */
552 AVIndexEntry *index_entries; /**< Only used if the format does not
553 support seeking natively. */
554 int nb_index_entries;
555 unsigned int index_entries_allocated_size;
557 int64_t nb_frames; ///< number of frames in this stream if known or 0
559 #if LIBAVFORMAT_VERSION_INT < (53<<16)
563 #if FF_API_OLD_METADATA
564 char *filename; /**< source filename of the stream */
567 int disposition; /**< AV_DISPOSITION_* bit field */
569 AVProbeData probe_data;
570 #define MAX_REORDER_DELAY 16
571 int64_t pts_buffer[MAX_REORDER_DELAY+1];
574 * sample aspect ratio (0 if unknown)
575 * - encoding: Set by user.
576 * - decoding: Set by libavformat.
578 AVRational sample_aspect_ratio;
580 AVMetadata *metadata;
582 /* Intended mostly for av_read_frame() support. Not supposed to be used by */
583 /* external applications; try to use something else if at all possible. */
584 const uint8_t *cur_ptr;
588 // Timestamp generation support:
590 * Timestamp corresponding to the last dts sync point.
592 * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
593 * a DTS is received from the underlying container. Otherwise set to
594 * AV_NOPTS_VALUE by default.
596 int64_t reference_dts;
599 * Number of packets to buffer for codec probing
600 * NOT PART OF PUBLIC API
602 #define MAX_PROBE_PACKETS 2500
606 * last packet in packet_buffer for this stream when muxing.
607 * used internally, NOT PART OF PUBLIC API, dont read or write from outside of libav*
609 struct AVPacketList *last_in_packet_buffer;
614 AVRational avg_frame_rate;
617 * Number of frames that have been demuxed during av_find_stream_info()
619 int codec_info_nb_frames;
622 * Stream informations used internally by av_find_stream_info()
624 #define MAX_STD_TIMEBASES (60*12+5)
627 int64_t duration_gcd;
629 double duration_error[MAX_STD_TIMEBASES];
630 int64_t codec_info_duration;
634 #define AV_PROGRAM_RUNNING 1
637 * New fields can be added to the end with minor version bumps.
638 * Removal, reordering and changes to existing fields require a major
640 * sizeof(AVProgram) must not be used outside libav*.
642 typedef struct AVProgram {
644 #if FF_API_OLD_METADATA
645 char *provider_name; ///< network name for DVB streams
646 char *name; ///< service name for DVB streams
649 enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
650 unsigned int *stream_index;
651 unsigned int nb_stream_indexes;
652 AVMetadata *metadata;
655 #define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
656 (streams are added dynamically) */
658 typedef struct AVChapter {
659 int id; ///< unique ID to identify the chapter
660 AVRational time_base; ///< time base in which the start/end timestamps are specified
661 int64_t start, end; ///< chapter start/end time in time_base units
662 #if FF_API_OLD_METADATA
663 char *title; ///< chapter title
665 AVMetadata *metadata;
668 #if FF_API_MAX_STREAMS
669 #define MAX_STREAMS 20
673 * Format I/O context.
674 * New fields can be added to the end with minor version bumps.
675 * Removal, reordering and changes to existing fields require a major
677 * sizeof(AVFormatContext) must not be used outside libav*.
679 typedef struct AVFormatContext {
680 const AVClass *av_class; /**< Set by avformat_alloc_context. */
681 /* Can only be iformat or oformat, not both at the same time. */
682 struct AVInputFormat *iformat;
683 struct AVOutputFormat *oformat;
686 unsigned int nb_streams;
687 #if FF_API_MAX_STREAMS
688 AVStream *streams[MAX_STREAMS];
692 char filename[1024]; /**< input or output filename */
695 #if FF_API_OLD_METADATA
701 int year; /**< ID3 year, 0 if none */
702 int track; /**< track number, 0 if none */
703 char genre[32]; /**< ID3 genre */
706 int ctx_flags; /**< Format-specific flags, see AVFMTCTX_xx */
707 /* private data for pts handling (do not modify directly). */
709 * This buffer is only needed when packets were already buffered but
710 * not decoded, for example to get the codec parameters in MPEG
713 struct AVPacketList *packet_buffer;
716 * Decoding: position of the first frame of the component, in
717 * AV_TIME_BASE fractional seconds. NEVER set this value directly:
718 * It is deduced from the AVStream values.
723 * Decoding: duration of the stream, in AV_TIME_BASE fractional
724 * seconds. Only set this value if you know none of the individual stream
725 * durations and also dont set any of them. This is deduced from the
726 * AVStream values if not set.
731 * decoding: total file size, 0 if unknown
736 * Decoding: total stream bitrate in bit/s, 0 if not
737 * available. Never set it directly if the file_size and the
738 * duration are known as FFmpeg can compute it automatically.
742 /* av_read_frame() support */
744 #if LIBAVFORMAT_VERSION_INT < (53<<16)
745 const uint8_t *cur_ptr_deprecated;
746 int cur_len_deprecated;
747 AVPacket cur_pkt_deprecated;
750 /* av_seek_frame() support */
751 int64_t data_offset; /**< offset of the first packet */
755 unsigned int packet_size;
759 #define AVFMT_NOOUTPUTLOOP -1
760 #define AVFMT_INFINITEOUTPUTLOOP 0
762 * number of times to loop output in formats that support it
767 #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
768 #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
769 #define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
770 #define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
771 #define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
772 #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
773 #define AVFMT_FLAG_RTP_HINT 0x0040 ///< Add RTP hinting to the output file
778 * decoding: size of data to probe; encoding: unused.
780 unsigned int probesize;
783 * Maximum time (in AV_TIME_BASE units) during which the input should
784 * be analyzed in av_find_stream_info().
786 int max_analyze_duration;
791 unsigned int nb_programs;
792 AVProgram **programs;
795 * Forced video codec_id.
796 * Demuxing: Set by user.
798 enum CodecID video_codec_id;
801 * Forced audio codec_id.
802 * Demuxing: Set by user.
804 enum CodecID audio_codec_id;
807 * Forced subtitle codec_id.
808 * Demuxing: Set by user.
810 enum CodecID subtitle_codec_id;
813 * Maximum amount of memory in bytes to use for the index of each stream.
814 * If the index exceeds this size, entries will be discarded as
815 * needed to maintain a smaller size. This can lead to slower or less
816 * accurate seeking (depends on demuxer).
817 * Demuxers for which a full in-memory index is mandatory will ignore
820 * demuxing: set by user
822 unsigned int max_index_size;
825 * Maximum amount of memory in bytes to use for buffering frames
826 * obtained from realtime capture devices.
828 unsigned int max_picture_buffer;
830 unsigned int nb_chapters;
831 AVChapter **chapters;
834 * Flags to enable debugging.
837 #define FF_FDEBUG_TS 0x0001
840 * Raw packets from the demuxer, prior to parsing and decoding.
841 * This buffer is used for buffering packets until the codec can
842 * be identified, as parsing cannot be done without knowing the
845 struct AVPacketList *raw_packet_buffer;
846 struct AVPacketList *raw_packet_buffer_end;
848 struct AVPacketList *packet_buffer_end;
850 AVMetadata *metadata;
853 * Remaining size available for raw_packet_buffer, in bytes.
854 * NOT PART OF PUBLIC API
856 #define RAW_PACKET_BUFFER_SIZE 2500000
857 int raw_packet_buffer_remaining_size;
860 * Start time of the stream in real world time, in microseconds
861 * since the unix epoch (00:00 1st January 1970). That is, pts=0
862 * in the stream was captured at this real world time.
863 * - encoding: Set by user.
864 * - decoding: Unused.
866 int64_t start_time_realtime;
869 typedef struct AVPacketList {
871 struct AVPacketList *next;
874 #if LIBAVFORMAT_VERSION_INT < (53<<16)
875 extern AVInputFormat *first_iformat;
876 extern AVOutputFormat *first_oformat;
880 * If f is NULL, returns the first registered input format,
881 * if f is non-NULL, returns the next registered input format after f
882 * or NULL if f is the last one.
884 AVInputFormat *av_iformat_next(AVInputFormat *f);
887 * If f is NULL, returns the first registered output format,
888 * if f is non-NULL, returns the next registered output format after f
889 * or NULL if f is the last one.
891 AVOutputFormat *av_oformat_next(AVOutputFormat *f);
893 enum CodecID av_guess_image2_codec(const char *filename);
895 /* XXX: Use automatic init with either ELF sections or C file parser */
899 void av_register_input_format(AVInputFormat *format);
900 void av_register_output_format(AVOutputFormat *format);
901 #if LIBAVFORMAT_VERSION_MAJOR < 53
902 attribute_deprecated AVOutputFormat *guess_stream_format(const char *short_name,
903 const char *filename,
904 const char *mime_type);
907 * @deprecated Use av_guess_format() instead.
909 attribute_deprecated AVOutputFormat *guess_format(const char *short_name,
910 const char *filename,
911 const char *mime_type);
915 * Return the output format in the list of registered output formats
916 * which best matches the provided parameters, or return NULL if
919 * @param short_name if non-NULL checks if short_name matches with the
920 * names of the registered formats
921 * @param filename if non-NULL checks if filename terminates with the
922 * extensions of the registered formats
923 * @param mime_type if non-NULL checks if mime_type matches with the
924 * MIME type of the registered formats
926 AVOutputFormat *av_guess_format(const char *short_name,
927 const char *filename,
928 const char *mime_type);
931 * Guess the codec ID based upon muxer and filename.
933 enum CodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
934 const char *filename, const char *mime_type,
935 enum AVMediaType type);
938 * Send a nice hexadecimal dump of a buffer to the specified file stream.
940 * @param f The file stream pointer where the dump should be sent to.
942 * @param size buffer size
944 * @see av_hex_dump_log, av_pkt_dump, av_pkt_dump_log
946 void av_hex_dump(FILE *f, uint8_t *buf, int size);
949 * Send a nice hexadecimal dump of a buffer to the log.
951 * @param avcl A pointer to an arbitrary struct of which the first field is a
952 * pointer to an AVClass struct.
953 * @param level The importance level of the message, lower values signifying
956 * @param size buffer size
958 * @see av_hex_dump, av_pkt_dump, av_pkt_dump_log
960 void av_hex_dump_log(void *avcl, int level, uint8_t *buf, int size);
963 * Send a nice dump of a packet to the specified file stream.
965 * @param f The file stream pointer where the dump should be sent to.
966 * @param pkt packet to dump
967 * @param dump_payload True if the payload must be displayed, too.
969 void av_pkt_dump(FILE *f, AVPacket *pkt, int dump_payload);
972 * Send a nice dump of a packet to the log.
974 * @param avcl A pointer to an arbitrary struct of which the first field is a
975 * pointer to an AVClass struct.
976 * @param level The importance level of the message, lower values signifying
978 * @param pkt packet to dump
979 * @param dump_payload True if the payload must be displayed, too.
981 void av_pkt_dump_log(void *avcl, int level, AVPacket *pkt, int dump_payload);
984 * Initialize libavformat and register all the muxers, demuxers and
985 * protocols. If you do not call this function, then you can select
986 * exactly which formats you want to support.
988 * @see av_register_input_format()
989 * @see av_register_output_format()
990 * @see av_register_protocol()
992 void av_register_all(void);
995 * Get the CodecID for the given codec tag tag.
996 * If no codec id is found returns CODEC_ID_NONE.
998 * @param tags list of supported codec_id-codec_tag pairs, as stored
999 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
1001 enum CodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
1004 * Get the codec tag for the given codec id id.
1005 * If no codec tag is found returns 0.
1007 * @param tags list of supported codec_id-codec_tag pairs, as stored
1008 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
1010 unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum CodecID id);
1012 /* media file input */
1015 * Find AVInputFormat based on the short name of the input format.
1017 AVInputFormat *av_find_input_format(const char *short_name);
1020 * Guess the file format.
1022 * @param is_opened Whether the file is already opened; determines whether
1023 * demuxers with or without AVFMT_NOFILE are probed.
1025 AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
1028 * Guess the file format.
1030 * @param is_opened Whether the file is already opened; determines whether
1031 * demuxers with or without AVFMT_NOFILE are probed.
1032 * @param score_max A probe score larger that this is required to accept a
1033 * detection, the variable is set to the actual detection
1035 * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
1036 * to retry with a larger probe buffer.
1038 AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max);
1041 * Allocate all the structures needed to read an input stream.
1042 * This does not open the needed codecs for decoding the stream[s].
1044 int av_open_input_stream(AVFormatContext **ic_ptr,
1045 ByteIOContext *pb, const char *filename,
1046 AVInputFormat *fmt, AVFormatParameters *ap);
1049 * Open a media file as input. The codecs are not opened. Only the file
1050 * header (if present) is read.
1052 * @param ic_ptr The opened media file handle is put here.
1053 * @param filename filename to open
1054 * @param fmt If non-NULL, force the file format to use.
1055 * @param buf_size optional buffer size (zero if default is OK)
1056 * @param ap Additional parameters needed when opening the file
1057 * (NULL if default).
1058 * @return 0 if OK, AVERROR_xxx otherwise
1060 int av_open_input_file(AVFormatContext **ic_ptr, const char *filename,
1063 AVFormatParameters *ap);
1065 #if LIBAVFORMAT_VERSION_MAJOR < 53
1067 * @deprecated Use avformat_alloc_context() instead.
1069 attribute_deprecated AVFormatContext *av_alloc_format_context(void);
1073 * Allocate an AVFormatContext.
1074 * Can be freed with av_free() but do not forget to free everything you
1075 * explicitly allocated as well!
1077 AVFormatContext *avformat_alloc_context(void);
1080 * Read packets of a media file to get stream information. This
1081 * is useful for file formats with no headers such as MPEG. This
1082 * function also computes the real framerate in case of MPEG-2 repeat
1084 * The logical file position is not changed by this function;
1085 * examined packets may be buffered for later processing.
1087 * @param ic media file handle
1088 * @return >=0 if OK, AVERROR_xxx on error
1089 * @todo Let the user decide somehow what information is needed so that
1090 * we do not waste time getting stuff the user does not need.
1092 int av_find_stream_info(AVFormatContext *ic);
1095 * Read a transport packet from a media file.
1097 * This function is obsolete and should never be used.
1098 * Use av_read_frame() instead.
1100 * @param s media file handle
1101 * @param pkt is filled
1102 * @return 0 if OK, AVERROR_xxx on error
1104 int av_read_packet(AVFormatContext *s, AVPacket *pkt);
1107 * Return the next frame of a stream.
1108 * This function returns what is stored in the file, and does not validate
1109 * that what is there are valid frames for the decoder. It will split what is
1110 * stored in the file into frames and return one for each call. It will not
1111 * omit invalid data between valid frames so as to give the decoder the maximum
1112 * information possible for decoding.
1114 * The returned packet is valid
1115 * until the next av_read_frame() or until av_close_input_file() and
1116 * must be freed with av_free_packet. For video, the packet contains
1117 * exactly one frame. For audio, it contains an integer number of
1118 * frames if each frame has a known fixed size (e.g. PCM or ADPCM
1119 * data). If the audio frames have a variable size (e.g. MPEG audio),
1120 * then it contains one frame.
1122 * pkt->pts, pkt->dts and pkt->duration are always set to correct
1123 * values in AVStream.time_base units (and guessed if the format cannot
1124 * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
1125 * has B-frames, so it is better to rely on pkt->dts if you do not
1126 * decompress the payload.
1128 * @return 0 if OK, < 0 on error or end of file
1130 int av_read_frame(AVFormatContext *s, AVPacket *pkt);
1133 * Seek to the keyframe at timestamp.
1134 * 'timestamp' in 'stream_index'.
1135 * @param stream_index If stream_index is (-1), a default
1136 * stream is selected, and timestamp is automatically converted
1137 * from AV_TIME_BASE units to the stream specific time_base.
1138 * @param timestamp Timestamp in AVStream.time_base units
1139 * or, if no stream is specified, in AV_TIME_BASE units.
1140 * @param flags flags which select direction and seeking mode
1141 * @return >= 0 on success
1143 int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
1147 * Seek to timestamp ts.
1148 * Seeking will be done so that the point from which all active streams
1149 * can be presented successfully will be closest to ts and within min/max_ts.
1150 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
1152 * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
1153 * are the file position (this may not be supported by all demuxers).
1154 * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
1155 * in the stream with stream_index (this may not be supported by all demuxers).
1156 * Otherwise all timestamps are in units of the stream selected by stream_index
1157 * or if stream_index is -1, in AV_TIME_BASE units.
1158 * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
1159 * keyframes (this may not be supported by all demuxers).
1161 * @param stream_index index of the stream which is used as time base reference
1162 * @param min_ts smallest acceptable timestamp
1163 * @param ts target timestamp
1164 * @param max_ts largest acceptable timestamp
1165 * @param flags flags
1166 * @return >=0 on success, error code otherwise
1168 * @note This is part of the new seek API which is still under construction.
1169 * Thus do not use this yet. It may change at any time, do not expect
1170 * ABI compatibility yet!
1172 int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
1175 * Start playing a network-based stream (e.g. RTSP stream) at the
1178 int av_read_play(AVFormatContext *s);
1181 * Pause a network-based stream (e.g. RTSP stream).
1183 * Use av_read_play() to resume it.
1185 int av_read_pause(AVFormatContext *s);
1188 * Free a AVFormatContext allocated by av_open_input_stream.
1189 * @param s context to free
1191 void av_close_input_stream(AVFormatContext *s);
1194 * Close a media file (but not its codecs).
1196 * @param s media file handle
1198 void av_close_input_file(AVFormatContext *s);
1201 * Add a new stream to a media file.
1203 * Can only be called in the read_header() function. If the flag
1204 * AVFMTCTX_NOHEADER is in the format context, then new streams
1205 * can be added in read_packet too.
1207 * @param s media file handle
1208 * @param id file-format-dependent stream ID
1210 AVStream *av_new_stream(AVFormatContext *s, int id);
1211 AVProgram *av_new_program(AVFormatContext *s, int id);
1214 * Add a new chapter.
1215 * This function is NOT part of the public API
1216 * and should ONLY be used by demuxers.
1218 * @param s media file handle
1219 * @param id unique ID for this chapter
1220 * @param start chapter start time in time_base units
1221 * @param end chapter end time in time_base units
1222 * @param title chapter title
1224 * @return AVChapter or NULL on error
1226 AVChapter *ff_new_chapter(AVFormatContext *s, int id, AVRational time_base,
1227 int64_t start, int64_t end, const char *title);
1230 * Set the pts for a given stream.
1233 * @param pts_wrap_bits number of bits effectively used by the pts
1234 * (used for wrap control, 33 is the value for MPEG)
1235 * @param pts_num numerator to convert to seconds (MPEG: 1)
1236 * @param pts_den denominator to convert to seconds (MPEG: 90000)
1238 void av_set_pts_info(AVStream *s, int pts_wrap_bits,
1239 unsigned int pts_num, unsigned int pts_den);
1241 #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
1242 #define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
1243 #define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
1244 #define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
1246 int av_find_default_stream_index(AVFormatContext *s);
1249 * Get the index for a specific timestamp.
1250 * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
1251 * to the timestamp which is <= the requested one, if backward
1252 * is 0, then it will be >=
1253 * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
1254 * @return < 0 if no such timestamp could be found
1256 int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
1259 * Ensure the index uses less memory than the maximum specified in
1260 * AVFormatContext.max_index_size by discarding entries if it grows
1262 * This function is not part of the public API and should only be called
1265 void ff_reduce_index(AVFormatContext *s, int stream_index);
1268 * Add an index entry into a sorted list. Update the entry if the list
1269 * already contains it.
1271 * @param timestamp timestamp in the time base of the given stream
1273 int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
1274 int size, int distance, int flags);
1277 * Perform a binary search using av_index_search_timestamp() and
1278 * AVInputFormat.read_timestamp().
1279 * This is not supposed to be called directly by a user application,
1281 * @param target_ts target timestamp in the time base of the given stream
1282 * @param stream_index stream number
1284 int av_seek_frame_binary(AVFormatContext *s, int stream_index,
1285 int64_t target_ts, int flags);
1288 * Update cur_dts of all streams based on the given timestamp and AVStream.
1290 * Stream ref_st unchanged, others set cur_dts in their native time base.
1291 * Only needed for timestamp wrapping or if (dts not set and pts!=dts).
1292 * @param timestamp new dts expressed in time_base of param ref_st
1293 * @param ref_st reference stream giving time_base of param timestamp
1295 void av_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp);
1298 * Perform a binary search using read_timestamp().
1299 * This is not supposed to be called directly by a user application,
1301 * @param target_ts target timestamp in the time base of the given stream
1302 * @param stream_index stream number
1304 int64_t av_gen_search(AVFormatContext *s, int stream_index,
1305 int64_t target_ts, int64_t pos_min,
1306 int64_t pos_max, int64_t pos_limit,
1307 int64_t ts_min, int64_t ts_max,
1308 int flags, int64_t *ts_ret,
1309 int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
1314 int av_set_parameters(AVFormatContext *s, AVFormatParameters *ap);
1317 * Split a URL string into components.
1319 * The pointers to buffers for storing individual components may be null,
1320 * in order to ignore that component. Buffers for components not found are
1321 * set to empty strings. If the port is not found, it is set to a negative
1324 * @param proto the buffer for the protocol
1325 * @param proto_size the size of the proto buffer
1326 * @param authorization the buffer for the authorization
1327 * @param authorization_size the size of the authorization buffer
1328 * @param hostname the buffer for the host name
1329 * @param hostname_size the size of the hostname buffer
1330 * @param port_ptr a pointer to store the port number in
1331 * @param path the buffer for the path
1332 * @param path_size the size of the path buffer
1333 * @param url the URL to split
1335 void av_url_split(char *proto, int proto_size,
1336 char *authorization, int authorization_size,
1337 char *hostname, int hostname_size,
1339 char *path, int path_size,
1343 * Allocate the stream private data and write the stream header to an
1344 * output media file.
1346 * @param s media file handle
1347 * @return 0 if OK, AVERROR_xxx on error
1349 int av_write_header(AVFormatContext *s);
1352 * Write a packet to an output media file.
1354 * The packet shall contain one audio or video frame.
1355 * The packet must be correctly interleaved according to the container
1356 * specification, if not then av_interleaved_write_frame must be used.
1358 * @param s media file handle
1359 * @param pkt The packet, which contains the stream_index, buf/buf_size,
1361 * @return < 0 on error, = 0 if OK, 1 if end of stream wanted
1363 int av_write_frame(AVFormatContext *s, AVPacket *pkt);
1366 * Write a packet to an output media file ensuring correct interleaving.
1368 * The packet must contain one audio or video frame.
1369 * If the packets are already correctly interleaved, the application should
1370 * call av_write_frame() instead as it is slightly faster. It is also important
1371 * to keep in mind that completely non-interleaved input will need huge amounts
1372 * of memory to interleave with this, so it is preferable to interleave at the
1375 * @param s media file handle
1376 * @param pkt The packet, which contains the stream_index, buf/buf_size,
1378 * @return < 0 on error, = 0 if OK, 1 if end of stream wanted
1380 int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
1383 * Interleave a packet per dts in an output media file.
1385 * Packets with pkt->destruct == av_destruct_packet will be freed inside this
1386 * function, so they cannot be used after it. Note that calling av_free_packet()
1387 * on them is still safe.
1389 * @param s media file handle
1390 * @param out the interleaved packet will be output here
1391 * @param pkt the input packet
1392 * @param flush 1 if no further packets are available as input and all
1393 * remaining packets should be output
1394 * @return 1 if a packet was output, 0 if no packet could be output,
1395 * < 0 if an error occurred
1397 int av_interleave_packet_per_dts(AVFormatContext *s, AVPacket *out,
1398 AVPacket *pkt, int flush);
1401 * Write the stream trailer to an output media file and free the
1402 * file private data.
1404 * May only be called after a successful call to av_write_header.
1406 * @param s media file handle
1407 * @return 0 if OK, AVERROR_xxx on error
1409 int av_write_trailer(AVFormatContext *s);
1411 void dump_format(AVFormatContext *ic,
1416 #if LIBAVFORMAT_VERSION_MAJOR < 53
1418 * Parse width and height out of string str.
1419 * @deprecated Use av_parse_video_frame_size instead.
1421 attribute_deprecated int parse_image_size(int *width_ptr, int *height_ptr,
1425 * Convert framerate from a string to a fraction.
1426 * @deprecated Use av_parse_video_frame_rate instead.
1428 attribute_deprecated int parse_frame_rate(int *frame_rate, int *frame_rate_base,
1433 * Parse datestr and return a corresponding number of microseconds.
1434 * @param datestr String representing a date or a duration.
1435 * - If a date the syntax is:
1437 * now|{[{YYYY-MM-DD|YYYYMMDD}[T|t| ]]{{HH[:MM[:SS[.m...]]]}|{HH[MM[SS[.m...]]]}}[Z|z]}
1439 * If the value is "now" it takes the current time.
1440 * Time is local time unless Z is appended, in which case it is
1441 * interpreted as UTC.
1442 * If the year-month-day part is not specified it takes the current
1444 * @return the number of microseconds since 1st of January, 1970 up to
1445 * the time of the parsed date or INT64_MIN if datestr cannot be
1446 * successfully parsed.
1447 * - If a duration the syntax is:
1449 * [-]HH[:MM[:SS[.m...]]]
1452 * @return the number of microseconds contained in a time interval
1453 * with the specified duration or INT64_MIN if datestr cannot be
1454 * successfully parsed.
1455 * @param duration Flag which tells how to interpret datestr, if
1456 * not zero datestr is interpreted as a duration, otherwise as a
1459 int64_t parse_date(const char *datestr, int duration);
1462 * Get the current time in microseconds.
1464 int64_t av_gettime(void);
1466 /* ffm-specific for ffserver */
1467 #define FFM_PACKET_SIZE 4096
1468 int64_t ffm_read_write_index(int fd);
1469 int ffm_write_write_index(int fd, int64_t pos);
1470 void ffm_set_write_index(AVFormatContext *s, int64_t pos, int64_t file_size);
1473 * Attempt to find a specific tag in a URL.
1475 * syntax: '?tag1=val1&tag2=val2...'. Little URL decoding is done.
1476 * Return 1 if found.
1478 int find_info_tag(char *arg, int arg_size, const char *tag1, const char *info);
1481 * Return in 'buf' the path with '%d' replaced by a number.
1483 * Also handles the '%0nd' format where 'n' is the total number
1484 * of digits and '%%'.
1486 * @param buf destination buffer
1487 * @param buf_size destination buffer size
1488 * @param path numbered sequence string
1489 * @param number frame number
1490 * @return 0 if OK, -1 on format error
1492 int av_get_frame_filename(char *buf, int buf_size,
1493 const char *path, int number);
1496 * Check whether filename actually is a numbered sequence generator.
1498 * @param filename possible numbered sequence string
1499 * @return 1 if a valid numbered sequence string, 0 otherwise
1501 int av_filename_number_test(const char *filename);
1504 * Generate an SDP for an RTP session.
1506 * @param ac array of AVFormatContexts describing the RTP streams. If the
1507 * array is composed by only one context, such context can contain
1508 * multiple AVStreams (one AVStream per RTP stream). Otherwise,
1509 * all the contexts in the array (an AVCodecContext per RTP stream)
1510 * must contain only one AVStream.
1511 * @param n_files number of AVCodecContexts contained in ac
1512 * @param buff buffer where the SDP will be stored (must be allocated by
1514 * @param size the size of the buffer
1515 * @return 0 if OK, AVERROR_xxx on error
1517 int avf_sdp_create(AVFormatContext *ac[], int n_files, char *buff, int size);
1520 * Return a positive value if the given filename has one of the given
1521 * extensions, 0 otherwise.
1523 * @param extensions a comma-separated list of filename extensions
1525 int av_match_ext(const char *filename, const char *extensions);
1527 #endif /* AVFORMAT_AVFORMAT_H */