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
26 * I return the LIBAVFORMAT_VERSION_INT constant. You got
27 * a fucking problem with that, douchebag?
29 unsigned avformat_version(void);
32 * Return the libavformat build-time configuration.
34 const char *avformat_configuration(void);
37 * Return the libavformat license.
39 const char *avformat_license(void);
42 #include <stdio.h> /* FILE */
43 #include "libavcodec/avcodec.h"
46 #include "libavformat/version.h"
48 struct AVFormatContext;
52 * Public Metadata API.
53 * The metadata API allows libavformat to export metadata tags to a client
54 * application using a sequence of key/value pairs. Like all strings in FFmpeg,
55 * metadata must be stored as UTF-8 encoded Unicode. Note that metadata
56 * exported by demuxers isn't checked to be valid UTF-8 in most cases.
57 * Important concepts to keep in mind:
58 * 1. Keys are unique; there can never be 2 tags with the same key. This is
59 * also meant semantically, i.e., a demuxer should not knowingly produce
60 * several keys that are literally different but semantically identical.
61 * E.g., key=Author5, key=Author6. In this example, all authors must be
62 * placed in the same tag.
63 * 2. Metadata is flat, not hierarchical; there are no subtags. If you
64 * want to store, e.g., the email address of the child of producer Alice
65 * and actor Bob, that could have key=alice_and_bobs_childs_email_address.
66 * 3. Several modifiers can be applied to the tag name. This is done by
67 * appending a dash character ('-') and the modifier name in the order
68 * they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng.
69 * a) language -- a tag whose value is localized for a particular language
70 * is appended with the ISO 639-2/B 3-letter language code.
71 * For example: Author-ger=Michael, Author-eng=Mike
72 * The original/default language is in the unqualified "Author" tag.
73 * A demuxer should set a default if it sets any translated tag.
74 * b) sorting -- a modified version of a tag that should be used for
75 * sorting will have '-sort' appended. E.g. artist="The Beatles",
76 * artist-sort="Beatles, The".
78 * 4. Demuxers attempt to export metadata in a generic format, however tags
79 * with no generic equivalents are left as they are stored in the container.
80 * Follows a list of generic tag names:
82 * album -- name of the set this work belongs to
83 * album_artist -- main creator of the set/album, if different from artist.
84 * e.g. "Various Artists" for compilation albums.
85 * artist -- main creator of the work
86 * comment -- any additional description of the file.
87 * composer -- who composed the work, if different from artist.
88 * copyright -- name of copyright holder.
89 * creation_time-- date when the file was created, preferably in ISO 8601.
90 * date -- date when the work was created, preferably in ISO 8601.
91 * disc -- number of a subset, e.g. disc in a multi-disc collection.
92 * encoder -- name/settings of the software/hardware that produced the file.
93 * encoded_by -- person/group who created the file.
94 * filename -- original name of the file.
95 * genre -- <self-evident>.
96 * language -- main language in which the work is performed, preferably
97 * in ISO 639-2 format.
98 * performer -- artist who performed the work, if different from artist.
99 * E.g for "Also sprach Zarathustra", artist would be "Richard
100 * Strauss" and performer "London Philharmonic Orchestra".
101 * publisher -- name of the label/publisher.
102 * service_name -- name of the service in broadcasting (channel name).
103 * service_provider -- name of the service provider in broadcasting.
104 * title -- name of the work.
105 * track -- number of this work in the set, can be in form current/total.
108 #define AV_METADATA_MATCH_CASE 1
109 #define AV_METADATA_IGNORE_SUFFIX 2
110 #define AV_METADATA_DONT_STRDUP_KEY 4
111 #define AV_METADATA_DONT_STRDUP_VAL 8
112 #define AV_METADATA_DONT_OVERWRITE 16 ///< Don't overwrite existing tags.
119 typedef struct AVMetadata AVMetadata;
120 #if FF_API_OLD_METADATA
121 typedef struct AVMetadataConv AVMetadataConv;
125 * Get a metadata element with matching key.
127 * @param prev Set to the previous matching element to find the next.
128 * If set to NULL the first matching element is returned.
129 * @param flags Allows case as well as suffix-insensitive comparisons.
130 * @return Found tag or NULL, changing key or value leads to undefined behavior.
133 av_metadata_get(AVMetadata *m, const char *key, const AVMetadataTag *prev, int flags);
135 #if FF_API_OLD_METADATA
137 * Set the given tag in *pm, overwriting an existing tag.
139 * @param pm pointer to a pointer to a metadata struct. If *pm is NULL
140 * a metadata struct is allocated and put in *pm.
141 * @param key tag key to add to *pm (will be av_strduped)
142 * @param value tag value to add to *pm (will be av_strduped)
143 * @return >= 0 on success otherwise an error code <0
144 * @deprecated Use av_metadata_set2() instead.
146 attribute_deprecated int av_metadata_set(AVMetadata **pm, const char *key, const char *value);
150 * Set the given tag in *pm, overwriting an existing tag.
152 * @param pm pointer to a pointer to a metadata struct. If *pm is NULL
153 * a metadata struct is allocated and put in *pm.
154 * @param key tag key to add to *pm (will be av_strduped depending on flags)
155 * @param value tag value to add to *pm (will be av_strduped depending on flags).
156 * Passing a NULL value will cause an existing tag to be deleted.
157 * @return >= 0 on success otherwise an error code <0
159 int av_metadata_set2(AVMetadata **pm, const char *key, const char *value, int flags);
161 #if FF_API_OLD_METADATA
163 * This function is provided for compatibility reason and currently does nothing.
165 attribute_deprecated void av_metadata_conv(struct AVFormatContext *ctx, const AVMetadataConv *d_conv,
166 const AVMetadataConv *s_conv);
170 * Copy metadata from one AVMetadata struct into another.
171 * @param dst pointer to a pointer to a AVMetadata struct. If *dst is NULL,
172 * this function will allocate a struct for you and put it in *dst
173 * @param src pointer to source AVMetadata struct
174 * @param flags flags to use when setting metadata in *dst
175 * @note metadata is read using the AV_METADATA_IGNORE_SUFFIX flag
177 void av_metadata_copy(AVMetadata **dst, AVMetadata *src, int flags);
180 * Free all the memory allocated for an AVMetadata struct.
182 void av_metadata_free(AVMetadata **m);
185 /* packet functions */
189 * Allocate and read the payload of a packet and initialize its
190 * fields with default values.
193 * @param size desired payload size
194 * @return >0 (read size) if OK, AVERROR_xxx otherwise
196 int av_get_packet(ByteIOContext *s, AVPacket *pkt, int size);
200 * Read data and append it to the current content of the AVPacket.
201 * If pkt->size is 0 this is identical to av_get_packet.
202 * Note that this uses av_grow_packet and thus involves a realloc
203 * which is inefficient. Thus this function should only be used
204 * when there is no reasonable way to know (an upper bound of)
208 * @param size amount of data to read
209 * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data
210 * will not be lost even if an error occurs.
212 int av_append_packet(ByteIOContext *s, AVPacket *pkt, int size);
214 /*************************************************/
215 /* fractional numbers for exact pts handling */
218 * The exact value of the fractional number is: 'val + num / den'.
219 * num is assumed to be 0 <= num < den.
221 typedef struct AVFrac {
222 int64_t val, num, den;
225 /*************************************************/
226 /* input/output formats */
231 * This structure contains the data a format has to probe a file.
233 typedef struct AVProbeData {
234 const char *filename;
235 unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
236 int buf_size; /**< Size of buf except extra allocated bytes */
239 #define AVPROBE_SCORE_MAX 100 ///< maximum score, half of that is used for file-extension-based detection
240 #define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
242 typedef struct AVFormatParameters {
243 AVRational time_base;
248 enum PixelFormat pix_fmt;
249 int channel; /**< Used to select DV channel. */
250 const char *standard; /**< TV standard, NTSC, PAL, SECAM */
251 unsigned int mpeg2ts_raw:1; /**< Force raw MPEG-2 transport stream output, if possible. */
252 unsigned int mpeg2ts_compute_pcr:1; /**< Compute exact PCR for each transport
253 stream packet (only meaningful if
254 mpeg2ts_raw is TRUE). */
255 unsigned int initial_pause:1; /**< Do not begin to play the stream
256 immediately (RTSP only). */
257 unsigned int prealloced_context:1;
258 #if FF_API_PARAMETERS_CODEC_ID
259 attribute_deprecated enum CodecID video_codec_id;
260 attribute_deprecated enum CodecID audio_codec_id;
262 } AVFormatParameters;
264 //! Demuxer will use url_fopen, no opened file should be provided by the caller.
265 #define AVFMT_NOFILE 0x0001
266 #define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
267 #define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
268 #define AVFMT_RAWPICTURE 0x0020 /**< Format wants AVPicture structure for
270 #define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
271 #define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
272 #define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
273 #define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */
274 #define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */
275 #define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */
276 #define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */
278 typedef struct AVOutputFormat {
281 * Descriptive name for the format, meant to be more human-readable
282 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
285 const char *long_name;
286 const char *mime_type;
287 const char *extensions; /**< comma-separated filename extensions */
289 * size of private data so that it can be allocated in the wrapper
293 enum CodecID audio_codec; /**< default audio codec */
294 enum CodecID video_codec; /**< default video codec */
295 int (*write_header)(struct AVFormatContext *);
296 int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
297 int (*write_trailer)(struct AVFormatContext *);
299 * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_GLOBALHEADER
303 * Currently only used to set pixel format if not YUV420P.
305 int (*set_parameters)(struct AVFormatContext *, AVFormatParameters *);
306 int (*interleave_packet)(struct AVFormatContext *, AVPacket *out,
307 AVPacket *in, int flush);
310 * List of supported codec_id-codec_tag pairs, ordered by "better
311 * choice first". The arrays are all terminated by CODEC_ID_NONE.
313 const struct AVCodecTag * const *codec_tag;
315 enum CodecID subtitle_codec; /**< default subtitle codec */
317 #if FF_API_OLD_METADATA
318 const AVMetadataConv *metadata_conv;
321 const AVClass *priv_class; ///< AVClass for the private context
324 struct AVOutputFormat *next;
327 typedef struct AVInputFormat {
329 * A comma separated list of short names for the format. New names
330 * may be appended with a minor bump.
335 * Descriptive name for the format, meant to be more human-readable
336 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
339 const char *long_name;
342 * Size of private data so that it can be allocated in the wrapper.
347 * Tell if a given file has a chance of being parsed as this format.
348 * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
349 * big so you do not have to check for that unless you need more.
351 int (*read_probe)(AVProbeData *);
354 * Read the format header and initialize the AVFormatContext
355 * structure. Return 0 if OK. 'ap' if non-NULL contains
356 * additional parameters. Only used in raw format right
357 * now. 'av_new_stream' should be called to create new streams.
359 int (*read_header)(struct AVFormatContext *,
360 AVFormatParameters *ap);
363 * Read one packet and put it in 'pkt'. pts and flags are also
364 * set. 'av_new_stream' can be called only if the flag
365 * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
366 * background thread).
367 * @return 0 on success, < 0 on error.
368 * When returning an error, pkt must not have been allocated
369 * or must be freed before returning
371 int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
374 * Close the stream. The AVFormatContext and AVStreams are not
375 * freed by this function
377 int (*read_close)(struct AVFormatContext *);
381 * Seek to a given timestamp relative to the frames in
382 * stream component stream_index.
383 * @param stream_index Must not be -1.
384 * @param flags Selects which direction should be preferred if no exact
385 * match is available.
386 * @return >= 0 on success (but not necessarily the new offset)
388 attribute_deprecated int (*read_seek)(struct AVFormatContext *,
389 int stream_index, int64_t timestamp, int flags);
392 * Gets the next timestamp in stream[stream_index].time_base units.
393 * @return the timestamp or AV_NOPTS_VALUE if an error occurred
395 int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
396 int64_t *pos, int64_t pos_limit);
399 * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER.
404 * If extensions are defined, then no probe is done. You should
405 * usually not use extension format guessing because it is not
408 const char *extensions;
411 * General purpose read-only value that the format can use.
416 * Start/resume playing - only meaningful if using a network-based format
419 int (*read_play)(struct AVFormatContext *);
422 * Pause playing - only meaningful if using a network-based format
425 int (*read_pause)(struct AVFormatContext *);
427 const struct AVCodecTag * const *codec_tag;
430 * Seek to timestamp ts.
431 * Seeking will be done so that the point from which all active streams
432 * can be presented successfully will be closest to ts and within min/max_ts.
433 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
435 int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
437 #if FF_API_OLD_METADATA
438 const AVMetadataConv *metadata_conv;
442 struct AVInputFormat *next;
445 enum AVStreamParseType {
447 AVSTREAM_PARSE_FULL, /**< full parsing and repack */
448 AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
449 AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
450 AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
453 typedef struct AVIndexEntry {
456 #define AVINDEX_KEYFRAME 0x0001
458 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).
459 int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
462 #define AV_DISPOSITION_DEFAULT 0x0001
463 #define AV_DISPOSITION_DUB 0x0002
464 #define AV_DISPOSITION_ORIGINAL 0x0004
465 #define AV_DISPOSITION_COMMENT 0x0008
466 #define AV_DISPOSITION_LYRICS 0x0010
467 #define AV_DISPOSITION_KARAOKE 0x0020
470 * Track should be used during playback by default.
471 * Useful for subtitle track that should be displayed
472 * even when user did not explicitly ask for subtitles.
474 #define AV_DISPOSITION_FORCED 0x0040
478 * New fields can be added to the end with minor version bumps.
479 * Removal, reordering and changes to existing fields require a major
481 * sizeof(AVStream) must not be used outside libav*.
483 typedef struct AVStream {
484 int index; /**< stream index in AVFormatContext */
485 int id; /**< format-specific stream ID */
486 AVCodecContext *codec; /**< codec context */
488 * Real base framerate of the stream.
489 * This is the lowest framerate with which all timestamps can be
490 * represented accurately (it is the least common multiple of all
491 * framerates in the stream). Note, this value is just a guess!
492 * For example, if the time base is 1/90000 and all frames have either
493 * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
495 AVRational r_frame_rate;
498 /* internal data used in av_find_stream_info() */
502 * encoding: pts generation when outputting stream
507 * This is the fundamental unit of time (in seconds) in terms
508 * of which frame timestamps are represented. For fixed-fps content,
509 * time base should be 1/framerate and timestamp increments should be 1.
511 AVRational time_base;
512 int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
513 /* ffmpeg.c private use */
514 int stream_copy; /**< If set, just copy stream. */
515 enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
517 //FIXME move stuff to a flags field?
519 * Quality, as it has been removed from AVCodecContext and put in AVVideoFrame.
520 * MN: dunno if that is the right place for it
525 * Decoding: pts of the first frame of the stream, in stream time base.
526 * Only set this if you are absolutely 100% sure that the value you set
527 * it to really is the pts of the first frame.
528 * This may be undefined (AV_NOPTS_VALUE).
529 * @note The ASF header does NOT contain a correct start_time the ASF
530 * demuxer must NOT set this.
535 * Decoding: duration of the stream, in stream time base.
536 * If a source file does not specify a duration, but does specify
537 * a bitrate, this value will be estimated from bitrate and file size.
541 #if FF_API_OLD_METADATA
542 attribute_deprecated char language[4]; /**< ISO 639-2/B 3-letter language code (empty string if undefined) */
545 /* av_read_frame() support */
546 enum AVStreamParseType need_parsing;
547 struct AVCodecParserContext *parser;
550 int last_IP_duration;
552 /* av_seek_frame() support */
553 AVIndexEntry *index_entries; /**< Only used if the format does not
554 support seeking natively. */
555 int nb_index_entries;
556 unsigned int index_entries_allocated_size;
558 int64_t nb_frames; ///< number of frames in this stream if known or 0
560 #if FF_API_LAVF_UNUSED
561 attribute_deprecated int64_t unused[4+1];
564 #if FF_API_OLD_METADATA
565 attribute_deprecated char *filename; /**< source filename of the stream */
568 int disposition; /**< AV_DISPOSITION_* bit field */
570 AVProbeData probe_data;
571 #define MAX_REORDER_DELAY 16
572 int64_t pts_buffer[MAX_REORDER_DELAY+1];
575 * sample aspect ratio (0 if unknown)
576 * - encoding: Set by user.
577 * - decoding: Set by libavformat.
579 AVRational sample_aspect_ratio;
581 AVMetadata *metadata;
583 /* Intended mostly for av_read_frame() support. Not supposed to be used by */
584 /* external applications; try to use something else if at all possible. */
585 const uint8_t *cur_ptr;
589 // Timestamp generation support:
591 * Timestamp corresponding to the last dts sync point.
593 * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
594 * a DTS is received from the underlying container. Otherwise set to
595 * AV_NOPTS_VALUE by default.
597 int64_t reference_dts;
600 * Number of packets to buffer for codec probing
601 * NOT PART OF PUBLIC API
603 #define MAX_PROBE_PACKETS 2500
607 * last packet in packet_buffer for this stream when muxing.
608 * used internally, NOT PART OF PUBLIC API, dont read or write from outside of libav*
610 struct AVPacketList *last_in_packet_buffer;
615 AVRational avg_frame_rate;
618 * Number of frames that have been demuxed during av_find_stream_info()
620 int codec_info_nb_frames;
623 * Stream informations used internally by av_find_stream_info()
625 #define MAX_STD_TIMEBASES (60*12+5)
628 int64_t duration_gcd;
630 double duration_error[MAX_STD_TIMEBASES];
631 int64_t codec_info_duration;
635 #define AV_PROGRAM_RUNNING 1
638 * New fields can be added to the end with minor version bumps.
639 * Removal, reordering and changes to existing fields require a major
641 * sizeof(AVProgram) must not be used outside libav*.
643 typedef struct AVProgram {
645 #if FF_API_OLD_METADATA
646 attribute_deprecated char *provider_name; ///< network name for DVB streams
647 attribute_deprecated char *name; ///< service name for DVB streams
650 enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
651 unsigned int *stream_index;
652 unsigned int nb_stream_indexes;
653 AVMetadata *metadata;
656 #define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
657 (streams are added dynamically) */
659 typedef struct AVChapter {
660 int id; ///< unique ID to identify the chapter
661 AVRational time_base; ///< time base in which the start/end timestamps are specified
662 int64_t start, end; ///< chapter start/end time in time_base units
663 #if FF_API_OLD_METADATA
664 attribute_deprecated char *title; ///< chapter title
666 AVMetadata *metadata;
669 #if FF_API_MAX_STREAMS
670 #define MAX_STREAMS 20
674 * Format I/O context.
675 * New fields can be added to the end with minor version bumps.
676 * Removal, reordering and changes to existing fields require a major
678 * sizeof(AVFormatContext) must not be used outside libav*.
680 typedef struct AVFormatContext {
681 const AVClass *av_class; /**< Set by avformat_alloc_context. */
682 /* Can only be iformat or oformat, not both at the same time. */
683 struct AVInputFormat *iformat;
684 struct AVOutputFormat *oformat;
687 unsigned int nb_streams;
688 #if FF_API_MAX_STREAMS
689 AVStream *streams[MAX_STREAMS];
693 char filename[1024]; /**< input or output filename */
696 #if FF_API_OLD_METADATA
697 attribute_deprecated char title[512];
698 attribute_deprecated char author[512];
699 attribute_deprecated char copyright[512];
700 attribute_deprecated char comment[512];
701 attribute_deprecated char album[512];
702 attribute_deprecated int year; /**< ID3 year, 0 if none */
703 attribute_deprecated int track; /**< track number, 0 if none */
704 attribute_deprecated char genre[32]; /**< ID3 genre */
707 int ctx_flags; /**< Format-specific flags, see AVFMTCTX_xx */
708 /* private data for pts handling (do not modify directly). */
710 * This buffer is only needed when packets were already buffered but
711 * not decoded, for example to get the codec parameters in MPEG
714 struct AVPacketList *packet_buffer;
717 * Decoding: position of the first frame of the component, in
718 * AV_TIME_BASE fractional seconds. NEVER set this value directly:
719 * It is deduced from the AVStream values.
724 * Decoding: duration of the stream, in AV_TIME_BASE fractional
725 * seconds. Only set this value if you know none of the individual stream
726 * durations and also dont set any of them. This is deduced from the
727 * AVStream values if not set.
732 * decoding: total file size, 0 if unknown
737 * Decoding: total stream bitrate in bit/s, 0 if not
738 * available. Never set it directly if the file_size and the
739 * duration are known as FFmpeg can compute it automatically.
743 /* av_read_frame() support */
745 #if FF_API_LAVF_UNUSED
746 const uint8_t *cur_ptr_deprecated;
747 int cur_len_deprecated;
748 AVPacket cur_pkt_deprecated;
751 /* av_seek_frame() support */
752 int64_t data_offset; /**< offset of the first packet */
756 unsigned int packet_size;
760 #define AVFMT_NOOUTPUTLOOP -1
761 #define AVFMT_INFINITEOUTPUTLOOP 0
763 * number of times to loop output in formats that support it
768 #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
769 #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
770 #define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
771 #define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
772 #define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
773 #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
774 #define AVFMT_FLAG_RTP_HINT 0x0040 ///< Add RTP hinting to the output file
779 * decoding: size of data to probe; encoding: unused.
781 unsigned int probesize;
784 * Maximum time (in AV_TIME_BASE units) during which the input should
785 * be analyzed in av_find_stream_info().
787 int max_analyze_duration;
792 unsigned int nb_programs;
793 AVProgram **programs;
796 * Forced video codec_id.
797 * Demuxing: Set by user.
799 enum CodecID video_codec_id;
802 * Forced audio codec_id.
803 * Demuxing: Set by user.
805 enum CodecID audio_codec_id;
808 * Forced subtitle codec_id.
809 * Demuxing: Set by user.
811 enum CodecID subtitle_codec_id;
814 * Maximum amount of memory in bytes to use for the index of each stream.
815 * If the index exceeds this size, entries will be discarded as
816 * needed to maintain a smaller size. This can lead to slower or less
817 * accurate seeking (depends on demuxer).
818 * Demuxers for which a full in-memory index is mandatory will ignore
821 * demuxing: set by user
823 unsigned int max_index_size;
826 * Maximum amount of memory in bytes to use for buffering frames
827 * obtained from realtime capture devices.
829 unsigned int max_picture_buffer;
831 unsigned int nb_chapters;
832 AVChapter **chapters;
835 * Flags to enable debugging.
838 #define FF_FDEBUG_TS 0x0001
841 * Raw packets from the demuxer, prior to parsing and decoding.
842 * This buffer is used for buffering packets until the codec can
843 * be identified, as parsing cannot be done without knowing the
846 struct AVPacketList *raw_packet_buffer;
847 struct AVPacketList *raw_packet_buffer_end;
849 struct AVPacketList *packet_buffer_end;
851 AVMetadata *metadata;
854 * Remaining size available for raw_packet_buffer, in bytes.
855 * NOT PART OF PUBLIC API
857 #define RAW_PACKET_BUFFER_SIZE 2500000
858 int raw_packet_buffer_remaining_size;
861 * Start time of the stream in real world time, in microseconds
862 * since the unix epoch (00:00 1st January 1970). That is, pts=0
863 * in the stream was captured at this real world time.
864 * - encoding: Set by user.
865 * - decoding: Unused.
867 int64_t start_time_realtime;
870 typedef struct AVPacketList {
872 struct AVPacketList *next;
875 #if FF_API_FIRST_FORMAT
876 attribute_deprecated extern AVInputFormat *first_iformat;
877 attribute_deprecated extern AVOutputFormat *first_oformat;
881 * If f is NULL, returns the first registered input format,
882 * if f is non-NULL, returns the next registered input format after f
883 * or NULL if f is the last one.
885 AVInputFormat *av_iformat_next(AVInputFormat *f);
888 * If f is NULL, returns the first registered output format,
889 * if f is non-NULL, returns the next registered output format after f
890 * or NULL if f is the last one.
892 AVOutputFormat *av_oformat_next(AVOutputFormat *f);
894 enum CodecID av_guess_image2_codec(const char *filename);
896 /* XXX: Use automatic init with either ELF sections or C file parser */
900 void av_register_input_format(AVInputFormat *format);
901 void av_register_output_format(AVOutputFormat *format);
902 #if FF_API_GUESS_FORMAT
903 attribute_deprecated AVOutputFormat *guess_stream_format(const char *short_name,
904 const char *filename,
905 const char *mime_type);
908 * @deprecated Use av_guess_format() instead.
910 attribute_deprecated AVOutputFormat *guess_format(const char *short_name,
911 const char *filename,
912 const char *mime_type);
916 * Return the output format in the list of registered output formats
917 * which best matches the provided parameters, or return NULL if
920 * @param short_name if non-NULL checks if short_name matches with the
921 * names of the registered formats
922 * @param filename if non-NULL checks if filename terminates with the
923 * extensions of the registered formats
924 * @param mime_type if non-NULL checks if mime_type matches with the
925 * MIME type of the registered formats
927 AVOutputFormat *av_guess_format(const char *short_name,
928 const char *filename,
929 const char *mime_type);
932 * Guess the codec ID based upon muxer and filename.
934 enum CodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
935 const char *filename, const char *mime_type,
936 enum AVMediaType type);
939 * Send a nice hexadecimal dump of a buffer to the specified file stream.
941 * @param f The file stream pointer where the dump should be sent to.
943 * @param size buffer size
945 * @see av_hex_dump_log, av_pkt_dump, av_pkt_dump_log
947 void av_hex_dump(FILE *f, uint8_t *buf, int size);
950 * Send a nice hexadecimal dump of a buffer to the log.
952 * @param avcl A pointer to an arbitrary struct of which the first field is a
953 * pointer to an AVClass struct.
954 * @param level The importance level of the message, lower values signifying
957 * @param size buffer size
959 * @see av_hex_dump, av_pkt_dump, av_pkt_dump_log
961 void av_hex_dump_log(void *avcl, int level, uint8_t *buf, int size);
964 * Send a nice dump of a packet to the specified file stream.
966 * @param f The file stream pointer where the dump should be sent to.
967 * @param pkt packet to dump
968 * @param dump_payload True if the payload must be displayed, too.
970 void av_pkt_dump(FILE *f, AVPacket *pkt, int dump_payload);
973 * Send a nice dump of a packet to the log.
975 * @param avcl A pointer to an arbitrary struct of which the first field is a
976 * pointer to an AVClass struct.
977 * @param level The importance level of the message, lower values signifying
979 * @param pkt packet to dump
980 * @param dump_payload True if the payload must be displayed, too.
982 void av_pkt_dump_log(void *avcl, int level, AVPacket *pkt, int dump_payload);
985 * Initialize libavformat and register all the muxers, demuxers and
986 * protocols. If you do not call this function, then you can select
987 * exactly which formats you want to support.
989 * @see av_register_input_format()
990 * @see av_register_output_format()
991 * @see av_register_protocol()
993 void av_register_all(void);
996 * Get the CodecID for the given codec tag tag.
997 * If no codec id is found returns CODEC_ID_NONE.
999 * @param tags list of supported codec_id-codec_tag pairs, as stored
1000 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
1002 enum CodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
1005 * Get the codec tag for the given codec id id.
1006 * If no codec tag is found returns 0.
1008 * @param tags list of supported codec_id-codec_tag pairs, as stored
1009 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
1011 unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum CodecID id);
1013 /* media file input */
1016 * Find AVInputFormat based on the short name of the input format.
1018 AVInputFormat *av_find_input_format(const char *short_name);
1021 * Guess the file format.
1023 * @param is_opened Whether the file is already opened; determines whether
1024 * demuxers with or without AVFMT_NOFILE are probed.
1026 AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
1029 * Guess the file format.
1031 * @param is_opened Whether the file is already opened; determines whether
1032 * demuxers with or without AVFMT_NOFILE are probed.
1033 * @param score_max A probe score larger that this is required to accept a
1034 * detection, the variable is set to the actual detection
1036 * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
1037 * to retry with a larger probe buffer.
1039 AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max);
1042 * Allocate all the structures needed to read an input stream.
1043 * This does not open the needed codecs for decoding the stream[s].
1045 int av_open_input_stream(AVFormatContext **ic_ptr,
1046 ByteIOContext *pb, const char *filename,
1047 AVInputFormat *fmt, AVFormatParameters *ap);
1050 * Open a media file as input. The codecs are not opened. Only the file
1051 * header (if present) is read.
1053 * @param ic_ptr The opened media file handle is put here.
1054 * @param filename filename to open
1055 * @param fmt If non-NULL, force the file format to use.
1056 * @param buf_size optional buffer size (zero if default is OK)
1057 * @param ap Additional parameters needed when opening the file
1058 * (NULL if default).
1059 * @return 0 if OK, AVERROR_xxx otherwise
1061 int av_open_input_file(AVFormatContext **ic_ptr, const char *filename,
1064 AVFormatParameters *ap);
1066 #if FF_API_ALLOC_FORMAT_CONTEXT
1068 * @deprecated Use avformat_alloc_context() instead.
1070 attribute_deprecated AVFormatContext *av_alloc_format_context(void);
1074 * Allocate an AVFormatContext.
1075 * Can be freed with av_free() but do not forget to free everything you
1076 * explicitly allocated as well!
1078 AVFormatContext *avformat_alloc_context(void);
1081 * Read packets of a media file to get stream information. This
1082 * is useful for file formats with no headers such as MPEG. This
1083 * function also computes the real framerate in case of MPEG-2 repeat
1085 * The logical file position is not changed by this function;
1086 * examined packets may be buffered for later processing.
1088 * @param ic media file handle
1089 * @return >=0 if OK, AVERROR_xxx on error
1090 * @todo Let the user decide somehow what information is needed so that
1091 * we do not waste time getting stuff the user does not need.
1093 int av_find_stream_info(AVFormatContext *ic);
1096 * Find the "best" stream in the file.
1097 * The best stream is determined according to various heuristics as the most
1098 * likely to be what the user expects.
1099 * If the decoder parameter is non-NULL, av_find_best_stream will find the
1100 * default decoder for the stream's codec; streams for which no decoder can
1101 * be found are ignored.
1103 * @param ic media file handle
1104 * @param type stream type: video, audio, subtitles, etc.
1105 * @param wanted_stream_nb user-requested stream number,
1106 * or -1 for automatic selection
1107 * @param related_stream try to find a stream related (eg. in the same
1108 * program) to this one, or -1 if none
1109 * @param decoder_ret if non-NULL, returns the decoder for the
1111 * @param flags flags; none are currently defined
1112 * @return the non-negative stream number in case of success,
1113 * AVERROR_STREAM_NOT_FOUND if no stream with the requested type
1115 * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
1116 * @note If av_find_best_stream returns successfully and decoder_ret is not
1117 * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
1119 int av_find_best_stream(AVFormatContext *ic,
1120 enum AVMediaType type,
1121 int wanted_stream_nb,
1123 AVCodec **decoder_ret,
1127 * Read a transport packet from a media file.
1129 * This function is obsolete and should never be used.
1130 * Use av_read_frame() instead.
1132 * @param s media file handle
1133 * @param pkt is filled
1134 * @return 0 if OK, AVERROR_xxx on error
1136 int av_read_packet(AVFormatContext *s, AVPacket *pkt);
1139 * Return the next frame of a stream.
1140 * This function returns what is stored in the file, and does not validate
1141 * that what is there are valid frames for the decoder. It will split what is
1142 * stored in the file into frames and return one for each call. It will not
1143 * omit invalid data between valid frames so as to give the decoder the maximum
1144 * information possible for decoding.
1146 * The returned packet is valid
1147 * until the next av_read_frame() or until av_close_input_file() and
1148 * must be freed with av_free_packet. For video, the packet contains
1149 * exactly one frame. For audio, it contains an integer number of
1150 * frames if each frame has a known fixed size (e.g. PCM or ADPCM
1151 * data). If the audio frames have a variable size (e.g. MPEG audio),
1152 * then it contains one frame.
1154 * pkt->pts, pkt->dts and pkt->duration are always set to correct
1155 * values in AVStream.time_base units (and guessed if the format cannot
1156 * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
1157 * has B-frames, so it is better to rely on pkt->dts if you do not
1158 * decompress the payload.
1160 * @return 0 if OK, < 0 on error or end of file
1162 int av_read_frame(AVFormatContext *s, AVPacket *pkt);
1165 * Seek to the keyframe at timestamp.
1166 * 'timestamp' in 'stream_index'.
1167 * @param stream_index If stream_index is (-1), a default
1168 * stream is selected, and timestamp is automatically converted
1169 * from AV_TIME_BASE units to the stream specific time_base.
1170 * @param timestamp Timestamp in AVStream.time_base units
1171 * or, if no stream is specified, in AV_TIME_BASE units.
1172 * @param flags flags which select direction and seeking mode
1173 * @return >= 0 on success
1175 int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
1179 * Seek to timestamp ts.
1180 * Seeking will be done so that the point from which all active streams
1181 * can be presented successfully will be closest to ts and within min/max_ts.
1182 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
1184 * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
1185 * are the file position (this may not be supported by all demuxers).
1186 * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
1187 * in the stream with stream_index (this may not be supported by all demuxers).
1188 * Otherwise all timestamps are in units of the stream selected by stream_index
1189 * or if stream_index is -1, in AV_TIME_BASE units.
1190 * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
1191 * keyframes (this may not be supported by all demuxers).
1193 * @param stream_index index of the stream which is used as time base reference
1194 * @param min_ts smallest acceptable timestamp
1195 * @param ts target timestamp
1196 * @param max_ts largest acceptable timestamp
1197 * @param flags flags
1198 * @return >=0 on success, error code otherwise
1200 * @note This is part of the new seek API which is still under construction.
1201 * Thus do not use this yet. It may change at any time, do not expect
1202 * ABI compatibility yet!
1204 int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
1207 * Start playing a network-based stream (e.g. RTSP stream) at the
1210 int av_read_play(AVFormatContext *s);
1213 * Pause a network-based stream (e.g. RTSP stream).
1215 * Use av_read_play() to resume it.
1217 int av_read_pause(AVFormatContext *s);
1220 * Free a AVFormatContext allocated by av_open_input_stream.
1221 * @param s context to free
1223 void av_close_input_stream(AVFormatContext *s);
1226 * Close a media file (but not its codecs).
1228 * @param s media file handle
1230 void av_close_input_file(AVFormatContext *s);
1233 * Add a new stream to a media file.
1235 * Can only be called in the read_header() function. If the flag
1236 * AVFMTCTX_NOHEADER is in the format context, then new streams
1237 * can be added in read_packet too.
1239 * @param s media file handle
1240 * @param id file-format-dependent stream ID
1242 AVStream *av_new_stream(AVFormatContext *s, int id);
1243 AVProgram *av_new_program(AVFormatContext *s, int id);
1246 * Add a new chapter.
1247 * This function is NOT part of the public API
1248 * and should ONLY be used by demuxers.
1250 * @param s media file handle
1251 * @param id unique ID for this chapter
1252 * @param start chapter start time in time_base units
1253 * @param end chapter end time in time_base units
1254 * @param title chapter title
1256 * @return AVChapter or NULL on error
1258 AVChapter *ff_new_chapter(AVFormatContext *s, int id, AVRational time_base,
1259 int64_t start, int64_t end, const char *title);
1262 * Set the pts for a given stream.
1265 * @param pts_wrap_bits number of bits effectively used by the pts
1266 * (used for wrap control, 33 is the value for MPEG)
1267 * @param pts_num numerator to convert to seconds (MPEG: 1)
1268 * @param pts_den denominator to convert to seconds (MPEG: 90000)
1270 void av_set_pts_info(AVStream *s, int pts_wrap_bits,
1271 unsigned int pts_num, unsigned int pts_den);
1273 #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
1274 #define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
1275 #define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
1276 #define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
1278 int av_find_default_stream_index(AVFormatContext *s);
1281 * Get the index for a specific timestamp.
1282 * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
1283 * to the timestamp which is <= the requested one, if backward
1284 * is 0, then it will be >=
1285 * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
1286 * @return < 0 if no such timestamp could be found
1288 int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
1291 * Ensure the index uses less memory than the maximum specified in
1292 * AVFormatContext.max_index_size by discarding entries if it grows
1294 * This function is not part of the public API and should only be called
1297 void ff_reduce_index(AVFormatContext *s, int stream_index);
1300 * Add an index entry into a sorted list. Update the entry if the list
1301 * already contains it.
1303 * @param timestamp timestamp in the time base of the given stream
1305 int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
1306 int size, int distance, int flags);
1309 * Perform a binary search using av_index_search_timestamp() and
1310 * AVInputFormat.read_timestamp().
1311 * This is not supposed to be called directly by a user application,
1313 * @param target_ts target timestamp in the time base of the given stream
1314 * @param stream_index stream number
1316 int av_seek_frame_binary(AVFormatContext *s, int stream_index,
1317 int64_t target_ts, int flags);
1320 * Update cur_dts of all streams based on the given timestamp and AVStream.
1322 * Stream ref_st unchanged, others set cur_dts in their native time base.
1323 * Only needed for timestamp wrapping or if (dts not set and pts!=dts).
1324 * @param timestamp new dts expressed in time_base of param ref_st
1325 * @param ref_st reference stream giving time_base of param timestamp
1327 void av_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp);
1330 * Perform a binary search using read_timestamp().
1331 * This is not supposed to be called directly by a user application,
1333 * @param target_ts target timestamp in the time base of the given stream
1334 * @param stream_index stream number
1336 int64_t av_gen_search(AVFormatContext *s, int stream_index,
1337 int64_t target_ts, int64_t pos_min,
1338 int64_t pos_max, int64_t pos_limit,
1339 int64_t ts_min, int64_t ts_max,
1340 int flags, int64_t *ts_ret,
1341 int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
1346 int av_set_parameters(AVFormatContext *s, AVFormatParameters *ap);
1349 * Split a URL string into components.
1351 * The pointers to buffers for storing individual components may be null,
1352 * in order to ignore that component. Buffers for components not found are
1353 * set to empty strings. If the port is not found, it is set to a negative
1356 * @param proto the buffer for the protocol
1357 * @param proto_size the size of the proto buffer
1358 * @param authorization the buffer for the authorization
1359 * @param authorization_size the size of the authorization buffer
1360 * @param hostname the buffer for the host name
1361 * @param hostname_size the size of the hostname buffer
1362 * @param port_ptr a pointer to store the port number in
1363 * @param path the buffer for the path
1364 * @param path_size the size of the path buffer
1365 * @param url the URL to split
1367 void av_url_split(char *proto, int proto_size,
1368 char *authorization, int authorization_size,
1369 char *hostname, int hostname_size,
1371 char *path, int path_size,
1375 * Allocate the stream private data and write the stream header to an
1376 * output media file.
1378 * @param s media file handle
1379 * @return 0 if OK, AVERROR_xxx on error
1381 int av_write_header(AVFormatContext *s);
1384 * Write a packet to an output media file.
1386 * The packet shall contain one audio or video frame.
1387 * The packet must be correctly interleaved according to the container
1388 * specification, if not then av_interleaved_write_frame must be used.
1390 * @param s media file handle
1391 * @param pkt The packet, which contains the stream_index, buf/buf_size,
1393 * @return < 0 on error, = 0 if OK, 1 if end of stream wanted
1395 int av_write_frame(AVFormatContext *s, AVPacket *pkt);
1398 * Write a packet to an output media file ensuring correct interleaving.
1400 * The packet must contain one audio or video frame.
1401 * If the packets are already correctly interleaved, the application should
1402 * call av_write_frame() instead as it is slightly faster. It is also important
1403 * to keep in mind that completely non-interleaved input will need huge amounts
1404 * of memory to interleave with this, so it is preferable to interleave at the
1407 * @param s media file handle
1408 * @param pkt The packet, which contains the stream_index, buf/buf_size,
1410 * @return < 0 on error, = 0 if OK, 1 if end of stream wanted
1412 int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
1415 * Interleave a packet per dts in an output media file.
1417 * Packets with pkt->destruct == av_destruct_packet will be freed inside this
1418 * function, so they cannot be used after it. Note that calling av_free_packet()
1419 * on them is still safe.
1421 * @param s media file handle
1422 * @param out the interleaved packet will be output here
1423 * @param pkt the input packet
1424 * @param flush 1 if no further packets are available as input and all
1425 * remaining packets should be output
1426 * @return 1 if a packet was output, 0 if no packet could be output,
1427 * < 0 if an error occurred
1429 int av_interleave_packet_per_dts(AVFormatContext *s, AVPacket *out,
1430 AVPacket *pkt, int flush);
1433 * Write the stream trailer to an output media file and free the
1434 * file private data.
1436 * May only be called after a successful call to av_write_header.
1438 * @param s media file handle
1439 * @return 0 if OK, AVERROR_xxx on error
1441 int av_write_trailer(AVFormatContext *s);
1443 void dump_format(AVFormatContext *ic,
1448 #if FF_API_PARSE_FRAME_PARAM
1450 * Parse width and height out of string str.
1451 * @deprecated Use av_parse_video_frame_size instead.
1453 attribute_deprecated int parse_image_size(int *width_ptr, int *height_ptr,
1457 * Convert framerate from a string to a fraction.
1458 * @deprecated Use av_parse_video_frame_rate instead.
1460 attribute_deprecated int parse_frame_rate(int *frame_rate, int *frame_rate_base,
1465 * Parse datestr and return a corresponding number of microseconds.
1466 * @param datestr String representing a date or a duration.
1467 * - If a date the syntax is:
1469 * now|{[{YYYY-MM-DD|YYYYMMDD}[T|t| ]]{{HH[:MM[:SS[.m...]]]}|{HH[MM[SS[.m...]]]}}[Z|z]}
1471 * If the value is "now" it takes the current time.
1472 * Time is local time unless Z is appended, in which case it is
1473 * interpreted as UTC.
1474 * If the year-month-day part is not specified it takes the current
1476 * @return the number of microseconds since 1st of January, 1970 up to
1477 * the time of the parsed date or INT64_MIN if datestr cannot be
1478 * successfully parsed.
1479 * - If a duration the syntax is:
1481 * [-]HH[:MM[:SS[.m...]]]
1484 * @return the number of microseconds contained in a time interval
1485 * with the specified duration or INT64_MIN if datestr cannot be
1486 * successfully parsed.
1487 * @param duration Flag which tells how to interpret datestr, if
1488 * not zero datestr is interpreted as a duration, otherwise as a
1491 int64_t parse_date(const char *datestr, int duration);
1494 * Get the current time in microseconds.
1496 int64_t av_gettime(void);
1498 /* ffm-specific for ffserver */
1499 #define FFM_PACKET_SIZE 4096
1500 int64_t ffm_read_write_index(int fd);
1501 int ffm_write_write_index(int fd, int64_t pos);
1502 void ffm_set_write_index(AVFormatContext *s, int64_t pos, int64_t file_size);
1505 * Attempt to find a specific tag in a URL.
1507 * syntax: '?tag1=val1&tag2=val2...'. Little URL decoding is done.
1508 * Return 1 if found.
1510 int find_info_tag(char *arg, int arg_size, const char *tag1, const char *info);
1513 * Return in 'buf' the path with '%d' replaced by a number.
1515 * Also handles the '%0nd' format where 'n' is the total number
1516 * of digits and '%%'.
1518 * @param buf destination buffer
1519 * @param buf_size destination buffer size
1520 * @param path numbered sequence string
1521 * @param number frame number
1522 * @return 0 if OK, -1 on format error
1524 int av_get_frame_filename(char *buf, int buf_size,
1525 const char *path, int number);
1528 * Check whether filename actually is a numbered sequence generator.
1530 * @param filename possible numbered sequence string
1531 * @return 1 if a valid numbered sequence string, 0 otherwise
1533 int av_filename_number_test(const char *filename);
1536 * Generate an SDP for an RTP session.
1538 * @param ac array of AVFormatContexts describing the RTP streams. If the
1539 * array is composed by only one context, such context can contain
1540 * multiple AVStreams (one AVStream per RTP stream). Otherwise,
1541 * all the contexts in the array (an AVCodecContext per RTP stream)
1542 * must contain only one AVStream.
1543 * @param n_files number of AVCodecContexts contained in ac
1544 * @param buff buffer where the SDP will be stored (must be allocated by
1546 * @param size the size of the buffer
1547 * @return 0 if OK, AVERROR_xxx on error
1549 int avf_sdp_create(AVFormatContext *ac[], int n_files, char *buff, int size);
1552 * Return a positive value if the given filename has one of the given
1553 * extensions, 0 otherwise.
1555 * @param extensions a comma-separated list of filename extensions
1557 int av_match_ext(const char *filename, const char *extensions);
1559 #endif /* AVFORMAT_AVFORMAT_H */