rtp: set the payload type as stream id
[libav.git] / libavformat / avformat.h
1 /*
2 * copyright (c) 2001 Fabrice Bellard
3 *
4 * This file is part of Libav.
5 *
6 * Libav is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * Libav is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with Libav; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #ifndef AVFORMAT_AVFORMAT_H
22 #define AVFORMAT_AVFORMAT_H
23
24 /**
25 * @file
26 * @ingroup libavf
27 * Main libavformat public API header
28 */
29
30 /**
31 * @defgroup libavf I/O and Muxing/Demuxing Library
32 * @{
33 *
34 * Libavformat (lavf) is a library for dealing with various media container
35 * formats. Its main two purposes are demuxing - i.e. splitting a media file
36 * into component streams, and the reverse process of muxing - writing supplied
37 * data in a specified container format. It also has an @ref lavf_io
38 * "I/O module" which supports a number of protocols for accessing the data (e.g.
39 * file, tcp, http and others). Before using lavf, you need to call
40 * av_register_all() to register all compiled muxers, demuxers and protocols.
41 * Unless you are absolutely sure you won't use libavformat's network
42 * capabilities, you should also call avformat_network_init().
43 *
44 * A supported input format is described by an AVInputFormat struct, conversely
45 * an output format is described by AVOutputFormat. You can iterate over all
46 * registered input/output formats using the av_iformat_next() /
47 * av_oformat_next() functions. The protocols layer is not part of the public
48 * API, so you can only get the names of supported protocols with the
49 * avio_enum_protocols() function.
50 *
51 * Main lavf structure used for both muxing and demuxing is AVFormatContext,
52 * which exports all information about the file being read or written. As with
53 * most Libav structures, its size is not part of public ABI, so it cannot be
54 * allocated on stack or directly with av_malloc(). To create an
55 * AVFormatContext, use avformat_alloc_context() (some functions, like
56 * avformat_open_input() might do that for you).
57 *
58 * Most importantly an AVFormatContext contains:
59 * @li the @ref AVFormatContext.iformat "input" or @ref AVFormatContext.oformat
60 * "output" format. It is either autodetected or set by user for input;
61 * always set by user for output.
62 * @li an @ref AVFormatContext.streams "array" of AVStreams, which describe all
63 * elementary streams stored in the file. AVStreams are typically referred to
64 * using their index in this array.
65 * @li an @ref AVFormatContext.pb "I/O context". It is either opened by lavf or
66 * set by user for input, always set by user for output (unless you are dealing
67 * with an AVFMT_NOFILE format).
68 *
69 * @section lavf_options Passing options to (de)muxers
70 * Lavf allows to configure muxers and demuxers using the @ref avoptions
71 * mechanism. Generic (format-independent) libavformat options are provided by
72 * AVFormatContext, they can be examined from a user program by calling
73 * av_opt_next() / av_opt_find() on an allocated AVFormatContext (or its AVClass
74 * from avformat_get_class()). Private (format-specific) options are provided by
75 * AVFormatContext.priv_data if and only if AVInputFormat.priv_class /
76 * AVOutputFormat.priv_class of the corresponding format struct is non-NULL.
77 * Further options may be provided by the @ref AVFormatContext.pb "I/O context",
78 * if its AVClass is non-NULL, and the protocols layer. See the discussion on
79 * nesting in @ref avoptions documentation to learn how to access those.
80 *
81 * @defgroup lavf_decoding Demuxing
82 * @{
83 * Demuxers read a media file and split it into chunks of data (@em packets). A
84 * @ref AVPacket "packet" contains one or more encoded frames which belongs to a
85 * single elementary stream. In the lavf API this process is represented by the
86 * avformat_open_input() function for opening a file, av_read_frame() for
87 * reading a single packet and finally avformat_close_input(), which does the
88 * cleanup.
89 *
90 * @section lavf_decoding_open Opening a media file
91 * The minimum information required to open a file is its URL or filename, which
92 * is passed to avformat_open_input(), as in the following code:
93 * @code
94 * const char *url = "in.mp3";
95 * AVFormatContext *s = NULL;
96 * int ret = avformat_open_input(&s, url, NULL, NULL);
97 * if (ret < 0)
98 * abort();
99 * @endcode
100 * The above code attempts to allocate an AVFormatContext, open the
101 * specified file (autodetecting the format) and read the header, exporting the
102 * information stored there into s. Some formats do not have a header or do not
103 * store enough information there, so it is recommended that you call the
104 * avformat_find_stream_info() function which tries to read and decode a few
105 * frames to find missing information.
106 *
107 * In some cases you might want to preallocate an AVFormatContext yourself with
108 * avformat_alloc_context() and do some tweaking on it before passing it to
109 * avformat_open_input(). One such case is when you want to use custom functions
110 * for reading input data instead of lavf internal I/O layer.
111 * To do that, create your own AVIOContext with avio_alloc_context(), passing
112 * your reading callbacks to it. Then set the @em pb field of your
113 * AVFormatContext to newly created AVIOContext.
114 *
115 * Since the format of the opened file is in general not known until after
116 * avformat_open_input() has returned, it is not possible to set demuxer private
117 * options on a preallocated context. Instead, the options should be passed to
118 * avformat_open_input() wrapped in an AVDictionary:
119 * @code
120 * AVDictionary *options = NULL;
121 * av_dict_set(&options, "video_size", "640x480", 0);
122 * av_dict_set(&options, "pixel_format", "rgb24", 0);
123 *
124 * if (avformat_open_input(&s, url, NULL, &options) < 0)
125 * abort();
126 * av_dict_free(&options);
127 * @endcode
128 * This code passes the private options 'video_size' and 'pixel_format' to the
129 * demuxer. They would be necessary for e.g. the rawvideo demuxer, since it
130 * cannot know how to interpret raw video data otherwise. If the format turns
131 * out to be something different than raw video, those options will not be
132 * recognized by the demuxer and therefore will not be applied. Such unrecognized
133 * options are then returned in the options dictionary (recognized options are
134 * consumed). The calling program can handle such unrecognized options as it
135 * wishes, e.g.
136 * @code
137 * AVDictionaryEntry *e;
138 * if (e = av_dict_get(options, "", NULL, AV_DICT_IGNORE_SUFFIX)) {
139 * fprintf(stderr, "Option %s not recognized by the demuxer.\n", e->key);
140 * abort();
141 * }
142 * @endcode
143 *
144 * After you have finished reading the file, you must close it with
145 * avformat_close_input(). It will free everything associated with the file.
146 *
147 * @section lavf_decoding_read Reading from an opened file
148 * Reading data from an opened AVFormatContext is done by repeatedly calling
149 * av_read_frame() on it. Each call, if successful, will return an AVPacket
150 * containing encoded data for one AVStream, identified by
151 * AVPacket.stream_index. This packet may be passed straight into the libavcodec
152 * decoding functions avcodec_decode_video2(), avcodec_decode_audio4() or
153 * avcodec_decode_subtitle2() if the caller wishes to decode the data.
154 *
155 * AVPacket.pts, AVPacket.dts and AVPacket.duration timing information will be
156 * set if known. They may also be unset (i.e. AV_NOPTS_VALUE for
157 * pts/dts, 0 for duration) if the stream does not provide them. The timing
158 * information will be in AVStream.time_base units, i.e. it has to be
159 * multiplied by the timebase to convert them to seconds.
160 *
161 * If AVPacket.destruct is set on the returned packet, then the packet is
162 * allocated dynamically and the user may keep it indefinitely.
163 * Otherwise, if AVPacket.destruct is NULL, the packet data is backed by a
164 * static storage somewhere inside the demuxer and the packet is only valid
165 * until the next av_read_frame() call or closing the file. If the caller
166 * requires a longer lifetime, av_dup_packet() will make an av_malloc()ed copy
167 * of it.
168 * In both cases, the packet must be freed with av_free_packet() when it is no
169 * longer needed.
170 *
171 * @section lavf_decoding_seek Seeking
172 * @}
173 *
174 * @defgroup lavf_encoding Muxing
175 * @{
176 * @}
177 *
178 * @defgroup lavf_io I/O Read/Write
179 * @{
180 * @}
181 *
182 * @defgroup lavf_codec Demuxers
183 * @{
184 * @defgroup lavf_codec_native Native Demuxers
185 * @{
186 * @}
187 * @defgroup lavf_codec_wrappers External library wrappers
188 * @{
189 * @}
190 * @}
191 * @defgroup lavf_protos I/O Protocols
192 * @{
193 * @}
194 * @defgroup lavf_internal Internal
195 * @{
196 * @}
197 * @}
198 *
199 */
200
201 #include <time.h>
202 #include <stdio.h> /* FILE */
203 #include "libavcodec/avcodec.h"
204 #include "libavutil/dict.h"
205 #include "libavutil/log.h"
206
207 #include "avio.h"
208 #include "libavformat/version.h"
209
210 #if FF_API_AV_GETTIME
211 #include "libavutil/time.h"
212 #endif
213
214 struct AVFormatContext;
215
216
217 /**
218 * @defgroup metadata_api Public Metadata API
219 * @{
220 * @ingroup libavf
221 * The metadata API allows libavformat to export metadata tags to a client
222 * application when demuxing. Conversely it allows a client application to
223 * set metadata when muxing.
224 *
225 * Metadata is exported or set as pairs of key/value strings in the 'metadata'
226 * fields of the AVFormatContext, AVStream, AVChapter and AVProgram structs
227 * using the @ref lavu_dict "AVDictionary" API. Like all strings in Libav,
228 * metadata is assumed to be UTF-8 encoded Unicode. Note that metadata
229 * exported by demuxers isn't checked to be valid UTF-8 in most cases.
230 *
231 * Important concepts to keep in mind:
232 * - Keys are unique; there can never be 2 tags with the same key. This is
233 * also meant semantically, i.e., a demuxer should not knowingly produce
234 * several keys that are literally different but semantically identical.
235 * E.g., key=Author5, key=Author6. In this example, all authors must be
236 * placed in the same tag.
237 * - Metadata is flat, not hierarchical; there are no subtags. If you
238 * want to store, e.g., the email address of the child of producer Alice
239 * and actor Bob, that could have key=alice_and_bobs_childs_email_address.
240 * - Several modifiers can be applied to the tag name. This is done by
241 * appending a dash character ('-') and the modifier name in the order
242 * they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng.
243 * - language -- a tag whose value is localized for a particular language
244 * is appended with the ISO 639-2/B 3-letter language code.
245 * For example: Author-ger=Michael, Author-eng=Mike
246 * The original/default language is in the unqualified "Author" tag.
247 * A demuxer should set a default if it sets any translated tag.
248 * - sorting -- a modified version of a tag that should be used for
249 * sorting will have '-sort' appended. E.g. artist="The Beatles",
250 * artist-sort="Beatles, The".
251 *
252 * - Demuxers attempt to export metadata in a generic format, however tags
253 * with no generic equivalents are left as they are stored in the container.
254 * Follows a list of generic tag names:
255 *
256 @verbatim
257 album -- name of the set this work belongs to
258 album_artist -- main creator of the set/album, if different from artist.
259 e.g. "Various Artists" for compilation albums.
260 artist -- main creator of the work
261 comment -- any additional description of the file.
262 composer -- who composed the work, if different from artist.
263 copyright -- name of copyright holder.
264 creation_time-- date when the file was created, preferably in ISO 8601.
265 date -- date when the work was created, preferably in ISO 8601.
266 disc -- number of a subset, e.g. disc in a multi-disc collection.
267 encoder -- name/settings of the software/hardware that produced the file.
268 encoded_by -- person/group who created the file.
269 filename -- original name of the file.
270 genre -- <self-evident>.
271 language -- main language in which the work is performed, preferably
272 in ISO 639-2 format. Multiple languages can be specified by
273 separating them with commas.
274 performer -- artist who performed the work, if different from artist.
275 E.g for "Also sprach Zarathustra", artist would be "Richard
276 Strauss" and performer "London Philharmonic Orchestra".
277 publisher -- name of the label/publisher.
278 service_name -- name of the service in broadcasting (channel name).
279 service_provider -- name of the service provider in broadcasting.
280 title -- name of the work.
281 track -- number of this work in the set, can be in form current/total.
282 variant_bitrate -- the total bitrate of the bitrate variant that the current stream is part of
283 @endverbatim
284 *
285 * Look in the examples section for an application example how to use the Metadata API.
286 *
287 * @}
288 */
289
290 /* packet functions */
291
292
293 /**
294 * Allocate and read the payload of a packet and initialize its
295 * fields with default values.
296 *
297 * @param pkt packet
298 * @param size desired payload size
299 * @return >0 (read size) if OK, AVERROR_xxx otherwise
300 */
301 int av_get_packet(AVIOContext *s, AVPacket *pkt, int size);
302
303
304 /**
305 * Read data and append it to the current content of the AVPacket.
306 * If pkt->size is 0 this is identical to av_get_packet.
307 * Note that this uses av_grow_packet and thus involves a realloc
308 * which is inefficient. Thus this function should only be used
309 * when there is no reasonable way to know (an upper bound of)
310 * the final size.
311 *
312 * @param pkt packet
313 * @param size amount of data to read
314 * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data
315 * will not be lost even if an error occurs.
316 */
317 int av_append_packet(AVIOContext *s, AVPacket *pkt, int size);
318
319 /*************************************************/
320 /* fractional numbers for exact pts handling */
321
322 /**
323 * The exact value of the fractional number is: 'val + num / den'.
324 * num is assumed to be 0 <= num < den.
325 */
326 typedef struct AVFrac {
327 int64_t val, num, den;
328 } AVFrac;
329
330 /*************************************************/
331 /* input/output formats */
332
333 struct AVCodecTag;
334
335 /**
336 * This structure contains the data a format has to probe a file.
337 */
338 typedef struct AVProbeData {
339 const char *filename;
340 unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
341 int buf_size; /**< Size of buf except extra allocated bytes */
342 } AVProbeData;
343
344 #define AVPROBE_SCORE_MAX 100 ///< maximum score, half of that is used for file-extension-based detection
345 #define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
346
347 /// Demuxer will use avio_open, no opened file should be provided by the caller.
348 #define AVFMT_NOFILE 0x0001
349 #define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
350 #define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
351 #define AVFMT_RAWPICTURE 0x0020 /**< Format wants AVPicture structure for
352 raw picture data. */
353 #define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
354 #define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
355 #define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
356 #define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */
357 #define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */
358 #define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */
359 #define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */
360 #define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fallback to binary search via read_timestamp */
361 #define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fallback to generic search */
362 #define AVFMT_NO_BYTE_SEEK 0x8000 /**< Format does not allow seeking by bytes */
363 #define AVFMT_ALLOW_FLUSH 0x10000 /**< Format allows flushing. If not set, the muxer will not receive a NULL packet in the write_packet function. */
364 #define AVFMT_TS_NONSTRICT 0x20000 /**< Format does not require strictly
365 increasing timestamps, but they must
366 still be monotonic */
367
368 /**
369 * @addtogroup lavf_encoding
370 * @{
371 */
372 typedef struct AVOutputFormat {
373 const char *name;
374 /**
375 * Descriptive name for the format, meant to be more human-readable
376 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
377 * to define it.
378 */
379 const char *long_name;
380 const char *mime_type;
381 const char *extensions; /**< comma-separated filename extensions */
382 /* output support */
383 enum AVCodecID audio_codec; /**< default audio codec */
384 enum AVCodecID video_codec; /**< default video codec */
385 enum AVCodecID subtitle_codec; /**< default subtitle codec */
386 /**
387 * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_RAWPICTURE,
388 * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
389 * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH,
390 * AVFMT_TS_NONSTRICT
391 */
392 int flags;
393
394 /**
395 * List of supported codec_id-codec_tag pairs, ordered by "better
396 * choice first". The arrays are all terminated by AV_CODEC_ID_NONE.
397 */
398 const struct AVCodecTag * const *codec_tag;
399
400
401 const AVClass *priv_class; ///< AVClass for the private context
402
403 /*****************************************************************
404 * No fields below this line are part of the public API. They
405 * may not be used outside of libavformat and can be changed and
406 * removed at will.
407 * New public fields should be added right above.
408 *****************************************************************
409 */
410 struct AVOutputFormat *next;
411 /**
412 * size of private data so that it can be allocated in the wrapper
413 */
414 int priv_data_size;
415
416 int (*write_header)(struct AVFormatContext *);
417 /**
418 * Write a packet. If AVFMT_ALLOW_FLUSH is set in flags,
419 * pkt can be NULL in order to flush data buffered in the muxer.
420 * When flushing, return 0 if there still is more data to flush,
421 * or 1 if everything was flushed and there is no more buffered
422 * data.
423 */
424 int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
425 int (*write_trailer)(struct AVFormatContext *);
426 /**
427 * Currently only used to set pixel format if not YUV420P.
428 */
429 int (*interleave_packet)(struct AVFormatContext *, AVPacket *out,
430 AVPacket *in, int flush);
431 /**
432 * Test if the given codec can be stored in this container.
433 *
434 * @return 1 if the codec is supported, 0 if it is not.
435 * A negative number if unknown.
436 */
437 int (*query_codec)(enum AVCodecID id, int std_compliance);
438 } AVOutputFormat;
439 /**
440 * @}
441 */
442
443 /**
444 * @addtogroup lavf_decoding
445 * @{
446 */
447 typedef struct AVInputFormat {
448 /**
449 * A comma separated list of short names for the format. New names
450 * may be appended with a minor bump.
451 */
452 const char *name;
453
454 /**
455 * Descriptive name for the format, meant to be more human-readable
456 * than name. You should use the NULL_IF_CONFIG_SMALL() macro
457 * to define it.
458 */
459 const char *long_name;
460
461 /**
462 * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
463 * AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
464 * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK.
465 */
466 int flags;
467
468 /**
469 * If extensions are defined, then no probe is done. You should
470 * usually not use extension format guessing because it is not
471 * reliable enough
472 */
473 const char *extensions;
474
475 const struct AVCodecTag * const *codec_tag;
476
477 const AVClass *priv_class; ///< AVClass for the private context
478
479 /*****************************************************************
480 * No fields below this line are part of the public API. They
481 * may not be used outside of libavformat and can be changed and
482 * removed at will.
483 * New public fields should be added right above.
484 *****************************************************************
485 */
486 struct AVInputFormat *next;
487
488 /**
489 * Raw demuxers store their codec ID here.
490 */
491 int raw_codec_id;
492
493 /**
494 * Size of private data so that it can be allocated in the wrapper.
495 */
496 int priv_data_size;
497
498 /**
499 * Tell if a given file has a chance of being parsed as this format.
500 * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
501 * big so you do not have to check for that unless you need more.
502 */
503 int (*read_probe)(AVProbeData *);
504
505 /**
506 * Read the format header and initialize the AVFormatContext
507 * structure. Return 0 if OK. Only used in raw format right
508 * now. 'avformat_new_stream' should be called to create new streams.
509 */
510 int (*read_header)(struct AVFormatContext *);
511
512 /**
513 * Read one packet and put it in 'pkt'. pts and flags are also
514 * set. 'avformat_new_stream' can be called only if the flag
515 * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
516 * background thread).
517 * @return 0 on success, < 0 on error.
518 * When returning an error, pkt must not have been allocated
519 * or must be freed before returning
520 */
521 int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
522
523 /**
524 * Close the stream. The AVFormatContext and AVStreams are not
525 * freed by this function
526 */
527 int (*read_close)(struct AVFormatContext *);
528
529 /**
530 * Seek to a given timestamp relative to the frames in
531 * stream component stream_index.
532 * @param stream_index Must not be -1.
533 * @param flags Selects which direction should be preferred if no exact
534 * match is available.
535 * @return >= 0 on success (but not necessarily the new offset)
536 */
537 int (*read_seek)(struct AVFormatContext *,
538 int stream_index, int64_t timestamp, int flags);
539
540 /**
541 * Get the next timestamp in stream[stream_index].time_base units.
542 * @return the timestamp or AV_NOPTS_VALUE if an error occurred
543 */
544 int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
545 int64_t *pos, int64_t pos_limit);
546
547 /**
548 * Start/resume playing - only meaningful if using a network-based format
549 * (RTSP).
550 */
551 int (*read_play)(struct AVFormatContext *);
552
553 /**
554 * Pause playing - only meaningful if using a network-based format
555 * (RTSP).
556 */
557 int (*read_pause)(struct AVFormatContext *);
558
559 /**
560 * Seek to timestamp ts.
561 * Seeking will be done so that the point from which all active streams
562 * can be presented successfully will be closest to ts and within min/max_ts.
563 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
564 */
565 int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
566 } AVInputFormat;
567 /**
568 * @}
569 */
570
571 enum AVStreamParseType {
572 AVSTREAM_PARSE_NONE,
573 AVSTREAM_PARSE_FULL, /**< full parsing and repack */
574 AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
575 AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
576 AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
577 };
578
579 typedef struct AVIndexEntry {
580 int64_t pos;
581 int64_t timestamp;
582 #define AVINDEX_KEYFRAME 0x0001
583 int flags:2;
584 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).
585 int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
586 } AVIndexEntry;
587
588 #define AV_DISPOSITION_DEFAULT 0x0001
589 #define AV_DISPOSITION_DUB 0x0002
590 #define AV_DISPOSITION_ORIGINAL 0x0004
591 #define AV_DISPOSITION_COMMENT 0x0008
592 #define AV_DISPOSITION_LYRICS 0x0010
593 #define AV_DISPOSITION_KARAOKE 0x0020
594
595 /**
596 * Track should be used during playback by default.
597 * Useful for subtitle track that should be displayed
598 * even when user did not explicitly ask for subtitles.
599 */
600 #define AV_DISPOSITION_FORCED 0x0040
601 #define AV_DISPOSITION_HEARING_IMPAIRED 0x0080 /**< stream for hearing impaired audiences */
602 #define AV_DISPOSITION_VISUAL_IMPAIRED 0x0100 /**< stream for visual impaired audiences */
603 #define AV_DISPOSITION_CLEAN_EFFECTS 0x0200 /**< stream without voice */
604 /**
605 * The stream is stored in the file as an attached picture/"cover art" (e.g.
606 * APIC frame in ID3v2). The single packet associated with it will be returned
607 * among the first few packets read from the file unless seeking takes place.
608 * It can also be accessed at any time in AVStream.attached_pic.
609 */
610 #define AV_DISPOSITION_ATTACHED_PIC 0x0400
611
612 /**
613 * Stream structure.
614 * New fields can be added to the end with minor version bumps.
615 * Removal, reordering and changes to existing fields require a major
616 * version bump.
617 * sizeof(AVStream) must not be used outside libav*.
618 */
619 typedef struct AVStream {
620 int index; /**< stream index in AVFormatContext */
621 /**
622 * Format-specific stream ID.
623 * decoding: set by libavformat
624 * encoding: set by the user, replaced by libavformat if left unset
625 */
626 int id;
627 /**
628 * Codec context associated with this stream. Allocated and freed by
629 * libavformat.
630 *
631 * - decoding: The demuxer exports codec information stored in the headers
632 * here.
633 * - encoding: The user sets codec information, the muxer writes it to the
634 * output. Mandatory fields as specified in AVCodecContext
635 * documentation must be set even if this AVCodecContext is
636 * not actually used for encoding.
637 */
638 AVCodecContext *codec;
639 #if FF_API_R_FRAME_RATE
640 /**
641 * Real base framerate of the stream.
642 * This is the lowest framerate with which all timestamps can be
643 * represented accurately (it is the least common multiple of all
644 * framerates in the stream). Note, this value is just a guess!
645 * For example, if the time base is 1/90000 and all frames have either
646 * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
647 */
648 AVRational r_frame_rate;
649 #endif
650 void *priv_data;
651
652 /**
653 * encoding: pts generation when outputting stream
654 */
655 struct AVFrac pts;
656
657 /**
658 * This is the fundamental unit of time (in seconds) in terms
659 * of which frame timestamps are represented.
660 *
661 * decoding: set by libavformat
662 * encoding: set by libavformat in avformat_write_header. The muxer may use the
663 * user-provided value of @ref AVCodecContext.time_base "codec->time_base"
664 * as a hint.
665 */
666 AVRational time_base;
667
668 /**
669 * Decoding: pts of the first frame of the stream, in stream time base.
670 * Only set this if you are absolutely 100% sure that the value you set
671 * it to really is the pts of the first frame.
672 * This may be undefined (AV_NOPTS_VALUE).
673 */
674 int64_t start_time;
675
676 /**
677 * Decoding: duration of the stream, in stream time base.
678 * If a source file does not specify a duration, but does specify
679 * a bitrate, this value will be estimated from bitrate and file size.
680 */
681 int64_t duration;
682
683 int64_t nb_frames; ///< number of frames in this stream if known or 0
684
685 int disposition; /**< AV_DISPOSITION_* bit field */
686
687 enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
688
689 /**
690 * sample aspect ratio (0 if unknown)
691 * - encoding: Set by user.
692 * - decoding: Set by libavformat.
693 */
694 AVRational sample_aspect_ratio;
695
696 AVDictionary *metadata;
697
698 /**
699 * Average framerate
700 */
701 AVRational avg_frame_rate;
702
703 /**
704 * For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet
705 * will contain the attached picture.
706 *
707 * decoding: set by libavformat, must not be modified by the caller.
708 * encoding: unused
709 */
710 AVPacket attached_pic;
711
712 /*****************************************************************
713 * All fields below this line are not part of the public API. They
714 * may not be used outside of libavformat and can be changed and
715 * removed at will.
716 * New public fields should be added right above.
717 *****************************************************************
718 */
719
720 /**
721 * Stream information used internally by av_find_stream_info()
722 */
723 #define MAX_STD_TIMEBASES (60*12+5)
724 struct {
725 #if FF_API_R_FRAME_RATE
726 int64_t last_dts;
727 int64_t duration_gcd;
728 int duration_count;
729 double duration_error[MAX_STD_TIMEBASES];
730 #endif
731 int nb_decoded_frames;
732 int found_decoder;
733
734 /**
735 * Those are used for average framerate estimation.
736 */
737 int64_t fps_first_dts;
738 int fps_first_dts_idx;
739 int64_t fps_last_dts;
740 int fps_last_dts_idx;
741
742 } *info;
743
744 int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
745
746 // Timestamp generation support:
747 /**
748 * Timestamp corresponding to the last dts sync point.
749 *
750 * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
751 * a DTS is received from the underlying container. Otherwise set to
752 * AV_NOPTS_VALUE by default.
753 */
754 int64_t reference_dts;
755 int64_t first_dts;
756 int64_t cur_dts;
757 int64_t last_IP_pts;
758 int last_IP_duration;
759
760 /**
761 * Number of packets to buffer for codec probing
762 */
763 #define MAX_PROBE_PACKETS 2500
764 int probe_packets;
765
766 /**
767 * Number of frames that have been demuxed during av_find_stream_info()
768 */
769 int codec_info_nb_frames;
770
771 /* av_read_frame() support */
772 enum AVStreamParseType need_parsing;
773 struct AVCodecParserContext *parser;
774
775 /**
776 * last packet in packet_buffer for this stream when muxing.
777 */
778 struct AVPacketList *last_in_packet_buffer;
779 AVProbeData probe_data;
780 #define MAX_REORDER_DELAY 16
781 int64_t pts_buffer[MAX_REORDER_DELAY+1];
782
783 AVIndexEntry *index_entries; /**< Only used if the format does not
784 support seeking natively. */
785 int nb_index_entries;
786 unsigned int index_entries_allocated_size;
787 } AVStream;
788
789 #define AV_PROGRAM_RUNNING 1
790
791 /**
792 * New fields can be added to the end with minor version bumps.
793 * Removal, reordering and changes to existing fields require a major
794 * version bump.
795 * sizeof(AVProgram) must not be used outside libav*.
796 */
797 typedef struct AVProgram {
798 int id;
799 int flags;
800 enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
801 unsigned int *stream_index;
802 unsigned int nb_stream_indexes;
803 AVDictionary *metadata;
804 } AVProgram;
805
806 #define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
807 (streams are added dynamically) */
808
809 typedef struct AVChapter {
810 int id; ///< unique ID to identify the chapter
811 AVRational time_base; ///< time base in which the start/end timestamps are specified
812 int64_t start, end; ///< chapter start/end time in time_base units
813 AVDictionary *metadata;
814 } AVChapter;
815
816 /**
817 * Format I/O context.
818 * New fields can be added to the end with minor version bumps.
819 * Removal, reordering and changes to existing fields require a major
820 * version bump.
821 * sizeof(AVFormatContext) must not be used outside libav*, use
822 * avformat_alloc_context() to create an AVFormatContext.
823 */
824 typedef struct AVFormatContext {
825 /**
826 * A class for logging and AVOptions. Set by avformat_alloc_context().
827 * Exports (de)muxer private options if they exist.
828 */
829 const AVClass *av_class;
830
831 /**
832 * Can only be iformat or oformat, not both at the same time.
833 *
834 * decoding: set by avformat_open_input().
835 * encoding: set by the user.
836 */
837 struct AVInputFormat *iformat;
838 struct AVOutputFormat *oformat;
839
840 /**
841 * Format private data. This is an AVOptions-enabled struct
842 * if and only if iformat/oformat.priv_class is not NULL.
843 */
844 void *priv_data;
845
846 /**
847 * I/O context.
848 *
849 * decoding: either set by the user before avformat_open_input() (then
850 * the user must close it manually) or set by avformat_open_input().
851 * encoding: set by the user.
852 *
853 * Do NOT set this field if AVFMT_NOFILE flag is set in
854 * iformat/oformat.flags. In such a case, the (de)muxer will handle
855 * I/O in some other way and this field will be NULL.
856 */
857 AVIOContext *pb;
858
859 /* stream info */
860 int ctx_flags; /**< Format-specific flags, see AVFMTCTX_xx */
861
862 /**
863 * A list of all streams in the file. New streams are created with
864 * avformat_new_stream().
865 *
866 * decoding: streams are created by libavformat in avformat_open_input().
867 * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
868 * appear in av_read_frame().
869 * encoding: streams are created by the user before avformat_write_header().
870 */
871 unsigned int nb_streams;
872 AVStream **streams;
873
874 char filename[1024]; /**< input or output filename */
875
876 /**
877 * Decoding: position of the first frame of the component, in
878 * AV_TIME_BASE fractional seconds. NEVER set this value directly:
879 * It is deduced from the AVStream values.
880 */
881 int64_t start_time;
882
883 /**
884 * Decoding: duration of the stream, in AV_TIME_BASE fractional
885 * seconds. Only set this value if you know none of the individual stream
886 * durations and also do not set any of them. This is deduced from the
887 * AVStream values if not set.
888 */
889 int64_t duration;
890
891 /**
892 * Decoding: total stream bitrate in bit/s, 0 if not
893 * available. Never set it directly if the file_size and the
894 * duration are known as Libav can compute it automatically.
895 */
896 int bit_rate;
897
898 unsigned int packet_size;
899 int max_delay;
900
901 int flags;
902 #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
903 #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
904 #define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
905 #define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
906 #define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
907 #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
908 #define AVFMT_FLAG_NOBUFFER 0x0040 ///< Do not buffer frames when possible
909 #define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
910 #define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted
911
912 /**
913 * decoding: size of data to probe; encoding: unused.
914 */
915 unsigned int probesize;
916
917 /**
918 * decoding: maximum time (in AV_TIME_BASE units) during which the input should
919 * be analyzed in avformat_find_stream_info().
920 */
921 int max_analyze_duration;
922
923 const uint8_t *key;
924 int keylen;
925
926 unsigned int nb_programs;
927 AVProgram **programs;
928
929 /**
930 * Forced video codec_id.
931 * Demuxing: Set by user.
932 */
933 enum AVCodecID video_codec_id;
934
935 /**
936 * Forced audio codec_id.
937 * Demuxing: Set by user.
938 */
939 enum AVCodecID audio_codec_id;
940
941 /**
942 * Forced subtitle codec_id.
943 * Demuxing: Set by user.
944 */
945 enum AVCodecID subtitle_codec_id;
946
947 /**
948 * Maximum amount of memory in bytes to use for the index of each stream.
949 * If the index exceeds this size, entries will be discarded as
950 * needed to maintain a smaller size. This can lead to slower or less
951 * accurate seeking (depends on demuxer).
952 * Demuxers for which a full in-memory index is mandatory will ignore
953 * this.
954 * muxing : unused
955 * demuxing: set by user
956 */
957 unsigned int max_index_size;
958
959 /**
960 * Maximum amount of memory in bytes to use for buffering frames
961 * obtained from realtime capture devices.
962 */
963 unsigned int max_picture_buffer;
964
965 unsigned int nb_chapters;
966 AVChapter **chapters;
967
968 AVDictionary *metadata;
969
970 /**
971 * Start time of the stream in real world time, in microseconds
972 * since the unix epoch (00:00 1st January 1970). That is, pts=0
973 * in the stream was captured at this real world time.
974 * - encoding: Set by user.
975 * - decoding: Unused.
976 */
977 int64_t start_time_realtime;
978
979 /**
980 * decoding: number of frames used to probe fps
981 */
982 int fps_probe_size;
983
984 /**
985 * Error recognition; higher values will detect more errors but may
986 * misdetect some more or less valid parts as errors.
987 * - encoding: unused
988 * - decoding: Set by user.
989 */
990 int error_recognition;
991
992 /**
993 * Custom interrupt callbacks for the I/O layer.
994 *
995 * decoding: set by the user before avformat_open_input().
996 * encoding: set by the user before avformat_write_header()
997 * (mainly useful for AVFMT_NOFILE formats). The callback
998 * should also be passed to avio_open2() if it's used to
999 * open the file.
1000 */
1001 AVIOInterruptCB interrupt_callback;
1002
1003 /**
1004 * Flags to enable debugging.
1005 */
1006 int debug;
1007 #define FF_FDEBUG_TS 0x0001
1008 /*****************************************************************
1009 * All fields below this line are not part of the public API. They
1010 * may not be used outside of libavformat and can be changed and
1011 * removed at will.
1012 * New public fields should be added right above.
1013 *****************************************************************
1014 */
1015
1016 /**
1017 * This buffer is only needed when packets were already buffered but
1018 * not decoded, for example to get the codec parameters in MPEG
1019 * streams.
1020 */
1021 struct AVPacketList *packet_buffer;
1022 struct AVPacketList *packet_buffer_end;
1023
1024 /* av_seek_frame() support */
1025 int64_t data_offset; /**< offset of the first packet */
1026
1027 /**
1028 * Raw packets from the demuxer, prior to parsing and decoding.
1029 * This buffer is used for buffering packets until the codec can
1030 * be identified, as parsing cannot be done without knowing the
1031 * codec.
1032 */
1033 struct AVPacketList *raw_packet_buffer;
1034 struct AVPacketList *raw_packet_buffer_end;
1035 /**
1036 * Packets split by the parser get queued here.
1037 */
1038 struct AVPacketList *parse_queue;
1039 struct AVPacketList *parse_queue_end;
1040 /**
1041 * Remaining size available for raw_packet_buffer, in bytes.
1042 */
1043 #define RAW_PACKET_BUFFER_SIZE 2500000
1044 int raw_packet_buffer_remaining_size;
1045 } AVFormatContext;
1046
1047 typedef struct AVPacketList {
1048 AVPacket pkt;
1049 struct AVPacketList *next;
1050 } AVPacketList;
1051
1052
1053 /**
1054 * @defgroup lavf_core Core functions
1055 * @ingroup libavf
1056 *
1057 * Functions for querying libavformat capabilities, allocating core structures,
1058 * etc.
1059 * @{
1060 */
1061
1062 /**
1063 * Return the LIBAVFORMAT_VERSION_INT constant.
1064 */
1065 unsigned avformat_version(void);
1066
1067 /**
1068 * Return the libavformat build-time configuration.
1069 */
1070 const char *avformat_configuration(void);
1071
1072 /**
1073 * Return the libavformat license.
1074 */
1075 const char *avformat_license(void);
1076
1077 /**
1078 * Initialize libavformat and register all the muxers, demuxers and
1079 * protocols. If you do not call this function, then you can select
1080 * exactly which formats you want to support.
1081 *
1082 * @see av_register_input_format()
1083 * @see av_register_output_format()
1084 * @see av_register_protocol()
1085 */
1086 void av_register_all(void);
1087
1088 void av_register_input_format(AVInputFormat *format);
1089 void av_register_output_format(AVOutputFormat *format);
1090
1091 /**
1092 * Do global initialization of network components. This is optional,
1093 * but recommended, since it avoids the overhead of implicitly
1094 * doing the setup for each session.
1095 *
1096 * Calling this function will become mandatory if using network
1097 * protocols at some major version bump.
1098 */
1099 int avformat_network_init(void);
1100
1101 /**
1102 * Undo the initialization done by avformat_network_init.
1103 */
1104 int avformat_network_deinit(void);
1105
1106 /**
1107 * If f is NULL, returns the first registered input format,
1108 * if f is non-NULL, returns the next registered input format after f
1109 * or NULL if f is the last one.
1110 */
1111 AVInputFormat *av_iformat_next(AVInputFormat *f);
1112
1113 /**
1114 * If f is NULL, returns the first registered output format,
1115 * if f is non-NULL, returns the next registered output format after f
1116 * or NULL if f is the last one.
1117 */
1118 AVOutputFormat *av_oformat_next(AVOutputFormat *f);
1119
1120 /**
1121 * Allocate an AVFormatContext.
1122 * avformat_free_context() can be used to free the context and everything
1123 * allocated by the framework within it.
1124 */
1125 AVFormatContext *avformat_alloc_context(void);
1126
1127 /**
1128 * Free an AVFormatContext and all its streams.
1129 * @param s context to free
1130 */
1131 void avformat_free_context(AVFormatContext *s);
1132
1133 /**
1134 * Get the AVClass for AVFormatContext. It can be used in combination with
1135 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
1136 *
1137 * @see av_opt_find().
1138 */
1139 const AVClass *avformat_get_class(void);
1140
1141 /**
1142 * Add a new stream to a media file.
1143 *
1144 * When demuxing, it is called by the demuxer in read_header(). If the
1145 * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
1146 * be called in read_packet().
1147 *
1148 * When muxing, should be called by the user before avformat_write_header().
1149 *
1150 * @param c If non-NULL, the AVCodecContext corresponding to the new stream
1151 * will be initialized to use this codec. This is needed for e.g. codec-specific
1152 * defaults to be set, so codec should be provided if it is known.
1153 *
1154 * @return newly created stream or NULL on error.
1155 */
1156 AVStream *avformat_new_stream(AVFormatContext *s, AVCodec *c);
1157
1158 AVProgram *av_new_program(AVFormatContext *s, int id);
1159
1160 /**
1161 * @}
1162 */
1163
1164
1165 /**
1166 * @addtogroup lavf_decoding
1167 * @{
1168 */
1169
1170 /**
1171 * Find AVInputFormat based on the short name of the input format.
1172 */
1173 AVInputFormat *av_find_input_format(const char *short_name);
1174
1175 /**
1176 * Guess the file format.
1177 *
1178 * @param is_opened Whether the file is already opened; determines whether
1179 * demuxers with or without AVFMT_NOFILE are probed.
1180 */
1181 AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
1182
1183 /**
1184 * Guess the file format.
1185 *
1186 * @param is_opened Whether the file is already opened; determines whether
1187 * demuxers with or without AVFMT_NOFILE are probed.
1188 * @param score_max A probe score larger that this is required to accept a
1189 * detection, the variable is set to the actual detection
1190 * score afterwards.
1191 * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
1192 * to retry with a larger probe buffer.
1193 */
1194 AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max);
1195
1196 /**
1197 * Probe a bytestream to determine the input format. Each time a probe returns
1198 * with a score that is too low, the probe buffer size is increased and another
1199 * attempt is made. When the maximum probe size is reached, the input format
1200 * with the highest score is returned.
1201 *
1202 * @param pb the bytestream to probe
1203 * @param fmt the input format is put here
1204 * @param filename the filename of the stream
1205 * @param logctx the log context
1206 * @param offset the offset within the bytestream to probe from
1207 * @param max_probe_size the maximum probe buffer size (zero for default)
1208 * @return 0 in case of success, a negative value corresponding to an
1209 * AVERROR code otherwise
1210 */
1211 int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt,
1212 const char *filename, void *logctx,
1213 unsigned int offset, unsigned int max_probe_size);
1214
1215 /**
1216 * Open an input stream and read the header. The codecs are not opened.
1217 * The stream must be closed with av_close_input_file().
1218 *
1219 * @param ps Pointer to user-supplied AVFormatContext (allocated by avformat_alloc_context).
1220 * May be a pointer to NULL, in which case an AVFormatContext is allocated by this
1221 * function and written into ps.
1222 * Note that a user-supplied AVFormatContext will be freed on failure.
1223 * @param filename Name of the stream to open.
1224 * @param fmt If non-NULL, this parameter forces a specific input format.
1225 * Otherwise the format is autodetected.
1226 * @param options A dictionary filled with AVFormatContext and demuxer-private options.
1227 * On return this parameter will be destroyed and replaced with a dict containing
1228 * options that were not found. May be NULL.
1229 *
1230 * @return 0 on success, a negative AVERROR on failure.
1231 *
1232 * @note If you want to use custom IO, preallocate the format context and set its pb field.
1233 */
1234 int avformat_open_input(AVFormatContext **ps, const char *filename, AVInputFormat *fmt, AVDictionary **options);
1235
1236 /**
1237 * Read packets of a media file to get stream information. This
1238 * is useful for file formats with no headers such as MPEG. This
1239 * function also computes the real framerate in case of MPEG-2 repeat
1240 * frame mode.
1241 * The logical file position is not changed by this function;
1242 * examined packets may be buffered for later processing.
1243 *
1244 * @param ic media file handle
1245 * @param options If non-NULL, an ic.nb_streams long array of pointers to
1246 * dictionaries, where i-th member contains options for
1247 * codec corresponding to i-th stream.
1248 * On return each dictionary will be filled with options that were not found.
1249 * @return >=0 if OK, AVERROR_xxx on error
1250 *
1251 * @note this function isn't guaranteed to open all the codecs, so
1252 * options being non-empty at return is a perfectly normal behavior.
1253 *
1254 * @todo Let the user decide somehow what information is needed so that
1255 * we do not waste time getting stuff the user does not need.
1256 */
1257 int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options);
1258
1259 /**
1260 * Find the "best" stream in the file.
1261 * The best stream is determined according to various heuristics as the most
1262 * likely to be what the user expects.
1263 * If the decoder parameter is non-NULL, av_find_best_stream will find the
1264 * default decoder for the stream's codec; streams for which no decoder can
1265 * be found are ignored.
1266 *
1267 * @param ic media file handle
1268 * @param type stream type: video, audio, subtitles, etc.
1269 * @param wanted_stream_nb user-requested stream number,
1270 * or -1 for automatic selection
1271 * @param related_stream try to find a stream related (eg. in the same
1272 * program) to this one, or -1 if none
1273 * @param decoder_ret if non-NULL, returns the decoder for the
1274 * selected stream
1275 * @param flags flags; none are currently defined
1276 * @return the non-negative stream number in case of success,
1277 * AVERROR_STREAM_NOT_FOUND if no stream with the requested type
1278 * could be found,
1279 * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
1280 * @note If av_find_best_stream returns successfully and decoder_ret is not
1281 * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
1282 */
1283 int av_find_best_stream(AVFormatContext *ic,
1284 enum AVMediaType type,
1285 int wanted_stream_nb,
1286 int related_stream,
1287 AVCodec **decoder_ret,
1288 int flags);
1289
1290 #if FF_API_READ_PACKET
1291 /**
1292 * @deprecated use AVFMT_FLAG_NOFILLIN | AVFMT_FLAG_NOPARSE to read raw
1293 * unprocessed packets
1294 *
1295 * Read a transport packet from a media file.
1296 *
1297 * This function is obsolete and should never be used.
1298 * Use av_read_frame() instead.
1299 *
1300 * @param s media file handle
1301 * @param pkt is filled
1302 * @return 0 if OK, AVERROR_xxx on error
1303 */
1304 attribute_deprecated
1305 int av_read_packet(AVFormatContext *s, AVPacket *pkt);
1306 #endif
1307
1308 /**
1309 * Return the next frame of a stream.
1310 * This function returns what is stored in the file, and does not validate
1311 * that what is there are valid frames for the decoder. It will split what is
1312 * stored in the file into frames and return one for each call. It will not
1313 * omit invalid data between valid frames so as to give the decoder the maximum
1314 * information possible for decoding.
1315 *
1316 * If pkt->destruct is NULL, then the packet is valid until the next
1317 * av_read_frame() or until av_close_input_file(). Otherwise the packet is valid
1318 * indefinitely. In both cases the packet must be freed with
1319 * av_free_packet when it is no longer needed. For video, the packet contains
1320 * exactly one frame. For audio, it contains an integer number of frames if each
1321 * frame has a known fixed size (e.g. PCM or ADPCM data). If the audio frames
1322 * have a variable size (e.g. MPEG audio), then it contains one frame.
1323 *
1324 * pkt->pts, pkt->dts and pkt->duration are always set to correct
1325 * values in AVStream.time_base units (and guessed if the format cannot
1326 * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
1327 * has B-frames, so it is better to rely on pkt->dts if you do not
1328 * decompress the payload.
1329 *
1330 * @return 0 if OK, < 0 on error or end of file
1331 */
1332 int av_read_frame(AVFormatContext *s, AVPacket *pkt);
1333
1334 /**
1335 * Seek to the keyframe at timestamp.
1336 * 'timestamp' in 'stream_index'.
1337 * @param stream_index If stream_index is (-1), a default
1338 * stream is selected, and timestamp is automatically converted
1339 * from AV_TIME_BASE units to the stream specific time_base.
1340 * @param timestamp Timestamp in AVStream.time_base units
1341 * or, if no stream is specified, in AV_TIME_BASE units.
1342 * @param flags flags which select direction and seeking mode
1343 * @return >= 0 on success
1344 */
1345 int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
1346 int flags);
1347
1348 /**
1349 * Seek to timestamp ts.
1350 * Seeking will be done so that the point from which all active streams
1351 * can be presented successfully will be closest to ts and within min/max_ts.
1352 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
1353 *
1354 * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
1355 * are the file position (this may not be supported by all demuxers).
1356 * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
1357 * in the stream with stream_index (this may not be supported by all demuxers).
1358 * Otherwise all timestamps are in units of the stream selected by stream_index
1359 * or if stream_index is -1, in AV_TIME_BASE units.
1360 * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
1361 * keyframes (this may not be supported by all demuxers).
1362 *
1363 * @param stream_index index of the stream which is used as time base reference
1364 * @param min_ts smallest acceptable timestamp
1365 * @param ts target timestamp
1366 * @param max_ts largest acceptable timestamp
1367 * @param flags flags
1368 * @return >=0 on success, error code otherwise
1369 *
1370 * @note This is part of the new seek API which is still under construction.
1371 * Thus do not use this yet. It may change at any time, do not expect
1372 * ABI compatibility yet!
1373 */
1374 int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
1375
1376 /**
1377 * Start playing a network-based stream (e.g. RTSP stream) at the
1378 * current position.
1379 */
1380 int av_read_play(AVFormatContext *s);
1381
1382 /**
1383 * Pause a network-based stream (e.g. RTSP stream).
1384 *
1385 * Use av_read_play() to resume it.
1386 */
1387 int av_read_pause(AVFormatContext *s);
1388
1389 #if FF_API_CLOSE_INPUT_FILE
1390 /**
1391 * @deprecated use avformat_close_input()
1392 * Close a media file (but not its codecs).
1393 *
1394 * @param s media file handle
1395 */
1396 attribute_deprecated
1397 void av_close_input_file(AVFormatContext *s);
1398 #endif
1399
1400 /**
1401 * Close an opened input AVFormatContext. Free it and all its contents
1402 * and set *s to NULL.
1403 */
1404 void avformat_close_input(AVFormatContext **s);
1405 /**
1406 * @}
1407 */
1408
1409 #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
1410 #define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
1411 #define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
1412 #define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
1413
1414 /**
1415 * @addtogroup lavf_encoding
1416 * @{
1417 */
1418 /**
1419 * Allocate the stream private data and write the stream header to
1420 * an output media file.
1421 *
1422 * @param s Media file handle, must be allocated with avformat_alloc_context().
1423 * Its oformat field must be set to the desired output format;
1424 * Its pb field must be set to an already openened AVIOContext.
1425 * @param options An AVDictionary filled with AVFormatContext and muxer-private options.
1426 * On return this parameter will be destroyed and replaced with a dict containing
1427 * options that were not found. May be NULL.
1428 *
1429 * @return 0 on success, negative AVERROR on failure.
1430 *
1431 * @see av_opt_find, av_dict_set, avio_open, av_oformat_next.
1432 */
1433 int avformat_write_header(AVFormatContext *s, AVDictionary **options);
1434
1435 /**
1436 * Write a packet to an output media file.
1437 *
1438 * The packet shall contain one audio or video frame.
1439 * The packet must be correctly interleaved according to the container
1440 * specification, if not then av_interleaved_write_frame must be used.
1441 *
1442 * @param s media file handle
1443 * @param pkt The packet, which contains the stream_index, buf/buf_size,
1444 * dts/pts, ...
1445 * This can be NULL (at any time, not just at the end), in
1446 * order to immediately flush data buffered within the muxer,
1447 * for muxers that buffer up data internally before writing it
1448 * to the output.
1449 * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush
1450 */
1451 int av_write_frame(AVFormatContext *s, AVPacket *pkt);
1452
1453 /**
1454 * Write a packet to an output media file ensuring correct interleaving.
1455 *
1456 * The packet must contain one audio or video frame.
1457 * If the packets are already correctly interleaved, the application should
1458 * call av_write_frame() instead as it is slightly faster. It is also important
1459 * to keep in mind that completely non-interleaved input will need huge amounts
1460 * of memory to interleave with this, so it is preferable to interleave at the
1461 * demuxer level.
1462 *
1463 * @param s media file handle
1464 * @param pkt The packet containing the data to be written. Libavformat takes
1465 * ownership of the data and will free it when it sees fit using the packet's
1466 * @ref AVPacket.destruct "destruct" field. The caller must not access the data
1467 * after this function returns, as it may already be freed.
1468 * This can be NULL (at any time, not just at the end), to flush the
1469 * interleaving queues.
1470 * Packet's @ref AVPacket.stream_index "stream_index" field must be set to the
1471 * index of the corresponding stream in @ref AVFormatContext.streams
1472 * "s.streams".
1473 * It is very strongly recommended that timing information (@ref AVPacket.pts
1474 * "pts", @ref AVPacket.dts "dts" @ref AVPacket.duration "duration") is set to
1475 * correct values.
1476 *
1477 * @return 0 on success, a negative AVERROR on error.
1478 */
1479 int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
1480
1481 #if FF_API_INTERLEAVE_PACKET
1482 /**
1483 * @deprecated this function was never meant to be called by the user
1484 * programs.
1485 */
1486 attribute_deprecated
1487 int av_interleave_packet_per_dts(AVFormatContext *s, AVPacket *out,
1488 AVPacket *pkt, int flush);
1489 #endif
1490
1491 /**
1492 * Write the stream trailer to an output media file and free the
1493 * file private data.
1494 *
1495 * May only be called after a successful call to avformat_write_header.
1496 *
1497 * @param s media file handle
1498 * @return 0 if OK, AVERROR_xxx on error
1499 */
1500 int av_write_trailer(AVFormatContext *s);
1501
1502 /**
1503 * Return the output format in the list of registered output formats
1504 * which best matches the provided parameters, or return NULL if
1505 * there is no match.
1506 *
1507 * @param short_name if non-NULL checks if short_name matches with the
1508 * names of the registered formats
1509 * @param filename if non-NULL checks if filename terminates with the
1510 * extensions of the registered formats
1511 * @param mime_type if non-NULL checks if mime_type matches with the
1512 * MIME type of the registered formats
1513 */
1514 AVOutputFormat *av_guess_format(const char *short_name,
1515 const char *filename,
1516 const char *mime_type);
1517
1518 /**
1519 * Guess the codec ID based upon muxer and filename.
1520 */
1521 enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
1522 const char *filename, const char *mime_type,
1523 enum AVMediaType type);
1524
1525 /**
1526 * @}
1527 */
1528
1529
1530 /**
1531 * @defgroup lavf_misc Utility functions
1532 * @ingroup libavf
1533 * @{
1534 *
1535 * Miscelaneous utility functions related to both muxing and demuxing
1536 * (or neither).
1537 */
1538
1539 /**
1540 * Send a nice hexadecimal dump of a buffer to the specified file stream.
1541 *
1542 * @param f The file stream pointer where the dump should be sent to.
1543 * @param buf buffer
1544 * @param size buffer size
1545 *
1546 * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2
1547 */
1548 void av_hex_dump(FILE *f, const uint8_t *buf, int size);
1549
1550 /**
1551 * Send a nice hexadecimal dump of a buffer to the log.
1552 *
1553 * @param avcl A pointer to an arbitrary struct of which the first field is a
1554 * pointer to an AVClass struct.
1555 * @param level The importance level of the message, lower values signifying
1556 * higher importance.
1557 * @param buf buffer
1558 * @param size buffer size
1559 *
1560 * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2
1561 */
1562 void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size);
1563
1564 /**
1565 * Send a nice dump of a packet to the specified file stream.
1566 *
1567 * @param f The file stream pointer where the dump should be sent to.
1568 * @param pkt packet to dump
1569 * @param dump_payload True if the payload must be displayed, too.
1570 * @param st AVStream that the packet belongs to
1571 */
1572 void av_pkt_dump2(FILE *f, AVPacket *pkt, int dump_payload, AVStream *st);
1573
1574
1575 /**
1576 * Send a nice dump of a packet to the log.
1577 *
1578 * @param avcl A pointer to an arbitrary struct of which the first field is a
1579 * pointer to an AVClass struct.
1580 * @param level The importance level of the message, lower values signifying
1581 * higher importance.
1582 * @param pkt packet to dump
1583 * @param dump_payload True if the payload must be displayed, too.
1584 * @param st AVStream that the packet belongs to
1585 */
1586 void av_pkt_dump_log2(void *avcl, int level, AVPacket *pkt, int dump_payload,
1587 AVStream *st);
1588
1589 /**
1590 * Get the AVCodecID for the given codec tag tag.
1591 * If no codec id is found returns AV_CODEC_ID_NONE.
1592 *
1593 * @param tags list of supported codec_id-codec_tag pairs, as stored
1594 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
1595 */
1596 enum AVCodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
1597
1598 /**
1599 * Get the codec tag for the given codec id id.
1600 * If no codec tag is found returns 0.
1601 *
1602 * @param tags list of supported codec_id-codec_tag pairs, as stored
1603 * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
1604 */
1605 unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id);
1606
1607 int av_find_default_stream_index(AVFormatContext *s);
1608
1609 /**
1610 * Get the index for a specific timestamp.
1611 * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
1612 * to the timestamp which is <= the requested one, if backward
1613 * is 0, then it will be >=
1614 * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
1615 * @return < 0 if no such timestamp could be found
1616 */
1617 int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
1618
1619 /**
1620 * Add an index entry into a sorted list. Update the entry if the list
1621 * already contains it.
1622 *
1623 * @param timestamp timestamp in the time base of the given stream
1624 */
1625 int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
1626 int size, int distance, int flags);
1627
1628
1629 /**
1630 * Split a URL string into components.
1631 *
1632 * The pointers to buffers for storing individual components may be null,
1633 * in order to ignore that component. Buffers for components not found are
1634 * set to empty strings. If the port is not found, it is set to a negative
1635 * value.
1636 *
1637 * @param proto the buffer for the protocol
1638 * @param proto_size the size of the proto buffer
1639 * @param authorization the buffer for the authorization
1640 * @param authorization_size the size of the authorization buffer
1641 * @param hostname the buffer for the host name
1642 * @param hostname_size the size of the hostname buffer
1643 * @param port_ptr a pointer to store the port number in
1644 * @param path the buffer for the path
1645 * @param path_size the size of the path buffer
1646 * @param url the URL to split
1647 */
1648 void av_url_split(char *proto, int proto_size,
1649 char *authorization, int authorization_size,
1650 char *hostname, int hostname_size,
1651 int *port_ptr,
1652 char *path, int path_size,
1653 const char *url);
1654
1655
1656 void av_dump_format(AVFormatContext *ic,
1657 int index,
1658 const char *url,
1659 int is_output);
1660
1661 /**
1662 * Return in 'buf' the path with '%d' replaced by a number.
1663 *
1664 * Also handles the '%0nd' format where 'n' is the total number
1665 * of digits and '%%'.
1666 *
1667 * @param buf destination buffer
1668 * @param buf_size destination buffer size
1669 * @param path numbered sequence string
1670 * @param number frame number
1671 * @return 0 if OK, -1 on format error
1672 */
1673 int av_get_frame_filename(char *buf, int buf_size,
1674 const char *path, int number);
1675
1676 /**
1677 * Check whether filename actually is a numbered sequence generator.
1678 *
1679 * @param filename possible numbered sequence string
1680 * @return 1 if a valid numbered sequence string, 0 otherwise
1681 */
1682 int av_filename_number_test(const char *filename);
1683
1684 /**
1685 * Generate an SDP for an RTP session.
1686 *
1687 * Note, this overwrites the id values of AVStreams in the muxer contexts
1688 * for getting unique dynamic payload types.
1689 *
1690 * @param ac array of AVFormatContexts describing the RTP streams. If the
1691 * array is composed by only one context, such context can contain
1692 * multiple AVStreams (one AVStream per RTP stream). Otherwise,
1693 * all the contexts in the array (an AVCodecContext per RTP stream)
1694 * must contain only one AVStream.
1695 * @param n_files number of AVCodecContexts contained in ac
1696 * @param buf buffer where the SDP will be stored (must be allocated by
1697 * the caller)
1698 * @param size the size of the buffer
1699 * @return 0 if OK, AVERROR_xxx on error
1700 */
1701 int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size);
1702
1703 /**
1704 * Return a positive value if the given filename has one of the given
1705 * extensions, 0 otherwise.
1706 *
1707 * @param extensions a comma-separated list of filename extensions
1708 */
1709 int av_match_ext(const char *filename, const char *extensions);
1710
1711 /**
1712 * Test if the given container can store a codec.
1713 *
1714 * @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
1715 *
1716 * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
1717 * A negative number if this information is not available.
1718 */
1719 int avformat_query_codec(AVOutputFormat *ofmt, enum AVCodecID codec_id, int std_compliance);
1720
1721 /**
1722 * @defgroup riff_fourcc RIFF FourCCs
1723 * @{
1724 * Get the tables mapping RIFF FourCCs to libavcodec AVCodecIDs. The tables are
1725 * meant to be passed to av_codec_get_id()/av_codec_get_tag() as in the
1726 * following code:
1727 * @code
1728 * uint32_t tag = MKTAG('H', '2', '6', '4');
1729 * const struct AVCodecTag *table[] = { avformat_get_riff_video_tags(), 0 };
1730 * enum AVCodecID id = av_codec_get_id(table, tag);
1731 * @endcode
1732 */
1733 /**
1734 * @return the table mapping RIFF FourCCs for video to libavcodec AVCodecID.
1735 */
1736 const struct AVCodecTag *avformat_get_riff_video_tags(void);
1737 /**
1738 * @return the table mapping RIFF FourCCs for audio to AVCodecID.
1739 */
1740 const struct AVCodecTag *avformat_get_riff_audio_tags(void);
1741 /**
1742 * @}
1743 */
1744
1745 /**
1746 * @}
1747 */
1748
1749 #endif /* AVFORMAT_AVFORMAT_H */