420125409db7d2bc284e921a3325db4ba6543a24
[libav.git] / libavformat / avformat.h
1 /*
2 * copyright (c) 2001 Fabrice Bellard
3 *
4 * This file is part of FFmpeg.
5 *
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.
10 *
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.
15 *
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
19 */
20
21 #ifndef AVFORMAT_AVFORMAT_H
22 #define AVFORMAT_AVFORMAT_H
23
24 #define LIBAVFORMAT_VERSION_MAJOR 52
25 #define LIBAVFORMAT_VERSION_MINOR 26
26 #define LIBAVFORMAT_VERSION_MICRO 0
27
28 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
29 LIBAVFORMAT_VERSION_MINOR, \
30 LIBAVFORMAT_VERSION_MICRO)
31 #define LIBAVFORMAT_VERSION AV_VERSION(LIBAVFORMAT_VERSION_MAJOR, \
32 LIBAVFORMAT_VERSION_MINOR, \
33 LIBAVFORMAT_VERSION_MICRO)
34 #define LIBAVFORMAT_BUILD LIBAVFORMAT_VERSION_INT
35
36 #define LIBAVFORMAT_IDENT "Lavf" AV_STRINGIFY(LIBAVFORMAT_VERSION)
37
38 /**
39 * Returns the LIBAVFORMAT_VERSION_INT constant.
40 */
41 unsigned avformat_version(void);
42
43 #include <time.h>
44 #include <stdio.h> /* FILE */
45 #include "libavcodec/avcodec.h"
46
47 #include "avio.h"
48
49
50 /*
51 * Public Metadata API.
52 * !!WARNING!! This is a work in progress. Don't use outside FFmpeg for now.
53 * The metadata API allows libavformat to export metadata tags to a client
54 * application using a sequence of key/value pairs.
55 * Important concepts to keep in mind:
56 * 1. Keys are unique; there can never be 2 tags with the same key. This is
57 * also meant semantically, i.e., a demuxer should not knowingly produce
58 * several keys that are literally different but semantically identical.
59 * E.g., key=Author5, key=Author6. In this example, all authors must be
60 * placed in the same tag.
61 * 2. Metadata is flat, not hierarchical; there are no subtags. If you
62 * want to store, e.g., the email address of the child of producer Alice
63 * and actor Bob, that could have key=alice_and_bobs_childs_email_address.
64 * 3. A tag whose value is localized for a particular language is appended
65 * with a dash character ('-') and the ISO 639 3-letter language code.
66 * For example: Author-ger=Michael, Author-eng=Mike
67 * The original/default language is in the unqualified "Author" tag.
68 * A demuxer should set a default if it sets any translated tag.
69 */
70
71 #define AV_METADATA_MATCH_CASE 1
72 #define AV_METADATA_IGNORE_SUFFIX 2
73
74 typedef struct {
75 char *key;
76 char *value;
77 }AVMetadataTag;
78
79 typedef struct AVMetadata AVMetadata;
80
81 /**
82 * gets a metadata element with matching key.
83 * @param prev set to the previous matching element to find the next.
84 * @param flags allows case as well as suffix insensitive comparisons.
85 * @return found tag or NULL, changing key or value leads to undefined behavior.
86 */
87 AVMetadataTag *
88 av_metadata_get(AVMetadata *m, const char *key, const AVMetadataTag *prev, int flags);
89
90 /**
91 * sets the given tag in m, overwriting an existing tag.
92 * @param key tag key to add to m (will be av_strduped).
93 * @param value tag value to add to m (will be av_strduped).
94 * @return >= 0 if success otherwise error code that is <0.
95 */
96 int av_metadata_set(AVMetadata **pm, const char *key, const char *value);
97
98 /**
99 * Free all the memory allocated for an AVMetadata struct.
100 */
101 void av_metadata_free(AVMetadata **m);
102
103
104 /* packet functions */
105
106 typedef struct AVPacket {
107 /**
108 * Presentation timestamp in time_base units.
109 * This is the time at which the decompressed packet will be presented
110 * to the user.
111 * Can be AV_NOPTS_VALUE if it is not stored in the file.
112 * pts MUST be larger or equal to dts as presentation cannot happen before
113 * decompression, unless one wants to view hex dumps. Some formats misuse
114 * the terms dts and pts/cts to mean something different, these timestamps
115 * must be converted to true pts/dts before they are stored in AVPacket.
116 */
117 int64_t pts;
118 /**
119 * Decompression timestamp in time_base units.
120 * This is the time at which the packet is decompressed.
121 * Can be AV_NOPTS_VALUE if it is not stored in the file.
122 */
123 int64_t dts;
124 uint8_t *data;
125 int size;
126 int stream_index;
127 int flags;
128 /**
129 * Duration of this packet in time_base units, 0 if unknown.
130 * Equals next_pts - this_pts in presentation order.
131 */
132 int duration;
133 void (*destruct)(struct AVPacket *);
134 void *priv;
135 int64_t pos; ///< byte position in stream, -1 if unknown
136
137 /**
138 * Time difference in stream time base units from the pts of this
139 * packet to the point at which the output from the decoder has converged
140 * independent from the availability of previous frames. That is, the
141 * frames are virtually identical no matter if decoding started from
142 * the very first frame or from this keyframe.
143 * Is AV_NOPTS_VALUE if unknown.
144 * This field is not the display duration of the current packet.
145 *
146 * The purpose of this field is to allow seeking in streams that have no
147 * keyframes in the conventional sense. It corresponds to the
148 * recovery point SEI in H.264 and match_time_delta in NUT. It is also
149 * essential for some types of subtitle streams to ensure that all
150 * subtitles are correctly displayed after seeking.
151 */
152 int64_t convergence_duration;
153 } AVPacket;
154 #define PKT_FLAG_KEY 0x0001
155
156 void av_destruct_packet_nofree(AVPacket *pkt);
157
158 /**
159 * Default packet destructor.
160 */
161 void av_destruct_packet(AVPacket *pkt);
162
163 /**
164 * Initialize optional fields of a packet with default values.
165 *
166 * @param pkt packet
167 */
168 void av_init_packet(AVPacket *pkt);
169
170 /**
171 * Allocate the payload of a packet and initialize its fields with
172 * default values.
173 *
174 * @param pkt packet
175 * @param size wanted payload size
176 * @return 0 if OK, AVERROR_xxx otherwise
177 */
178 int av_new_packet(AVPacket *pkt, int size);
179
180 /**
181 * Allocate and read the payload of a packet and initialize its fields with
182 * default values.
183 *
184 * @param pkt packet
185 * @param size desired payload size
186 * @return >0 (read size) if OK, AVERROR_xxx otherwise
187 */
188 int av_get_packet(ByteIOContext *s, AVPacket *pkt, int size);
189
190 /**
191 * @warning This is a hack - the packet memory allocation stuff is broken. The
192 * packet is allocated if it was not really allocated.
193 */
194 int av_dup_packet(AVPacket *pkt);
195
196 /**
197 * Free a packet.
198 *
199 * @param pkt packet to free
200 */
201 static inline void av_free_packet(AVPacket *pkt)
202 {
203 if (pkt && pkt->destruct) {
204 pkt->destruct(pkt);
205 }
206 }
207
208 /*************************************************/
209 /* fractional numbers for exact pts handling */
210
211 /**
212 * The exact value of the fractional number is: 'val + num / den'.
213 * num is assumed to be 0 <= num < den.
214 * @deprecated Use AVRational instead.
215 */
216 typedef struct AVFrac {
217 int64_t val, num, den;
218 } AVFrac;
219
220 /*************************************************/
221 /* input/output formats */
222
223 struct AVCodecTag;
224
225 struct AVFormatContext;
226
227 /** This structure contains the data a format has to probe a file. */
228 typedef struct AVProbeData {
229 const char *filename;
230 unsigned char *buf;
231 int buf_size;
232 } AVProbeData;
233
234 #define AVPROBE_SCORE_MAX 100 ///< Maximum score, half of that is used for file-extension-based detection.
235 #define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
236
237 typedef struct AVFormatParameters {
238 AVRational time_base;
239 int sample_rate;
240 int channels;
241 int width;
242 int height;
243 enum PixelFormat pix_fmt;
244 int channel; /**< Used to select DV channel. */
245 const char *standard; /**< TV standard, NTSC, PAL, SECAM */
246 unsigned int mpeg2ts_raw:1; /**< Force raw MPEG-2 transport stream output, if possible. */
247 unsigned int mpeg2ts_compute_pcr:1; /**< Compute exact PCR for each transport
248 stream packet (only meaningful if
249 mpeg2ts_raw is TRUE). */
250 unsigned int initial_pause:1; /**< Do not begin to play the stream
251 immediately (RTSP only). */
252 unsigned int prealloced_context:1;
253 #if LIBAVFORMAT_VERSION_INT < (53<<16)
254 enum CodecID video_codec_id;
255 enum CodecID audio_codec_id;
256 #endif
257 } AVFormatParameters;
258
259 //! Demuxer will use url_fopen, no opened file should be provided by the caller.
260 #define AVFMT_NOFILE 0x0001
261 #define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
262 #define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
263 #define AVFMT_RAWPICTURE 0x0020 /**< Format wants AVPicture structure for
264 raw picture data. */
265 #define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
266 #define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
267 #define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
268 #define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. */
269
270 typedef struct AVOutputFormat {
271 const char *name;
272 /**
273 * Descriptive name for the format, meant to be more human-readable
274 * than \p name. You \e should use the NULL_IF_CONFIG_SMALL() macro
275 * to define it.
276 */
277 const char *long_name;
278 const char *mime_type;
279 const char *extensions; /**< comma-separated filename extensions */
280 /** Size of private data so that it can be allocated in the wrapper. */
281 int priv_data_size;
282 /* output support */
283 enum CodecID audio_codec; /**< default audio codec */
284 enum CodecID video_codec; /**< default video codec */
285 int (*write_header)(struct AVFormatContext *);
286 int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
287 int (*write_trailer)(struct AVFormatContext *);
288 /** can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_GLOBALHEADER */
289 int flags;
290 /** Currently only used to set pixel format if not YUV420P. */
291 int (*set_parameters)(struct AVFormatContext *, AVFormatParameters *);
292 int (*interleave_packet)(struct AVFormatContext *, AVPacket *out,
293 AVPacket *in, int flush);
294
295 /**
296 * List of supported codec_id-codec_tag pairs, ordered by "better
297 * choice first". The arrays are all CODEC_ID_NONE terminated.
298 */
299 const struct AVCodecTag * const *codec_tag;
300
301 enum CodecID subtitle_codec; /**< default subtitle codec */
302
303 /* private fields */
304 struct AVOutputFormat *next;
305 } AVOutputFormat;
306
307 typedef struct AVInputFormat {
308 const char *name;
309 /**
310 * Descriptive name for the format, meant to be more human-readable
311 * than \p name. You \e should use the NULL_IF_CONFIG_SMALL() macro
312 * to define it.
313 */
314 const char *long_name;
315 /** Size of private data so that it can be allocated in the wrapper. */
316 int priv_data_size;
317 /**
318 * Tell if a given file has a chance of being parsed by this format.
319 * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
320 * big so you do not have to check for that unless you need more.
321 */
322 int (*read_probe)(AVProbeData *);
323 /** Read the format header and initialize the AVFormatContext
324 structure. Return 0 if OK. 'ap' if non-NULL contains
325 additional parameters. Only used in raw format right
326 now. 'av_new_stream' should be called to create new streams. */
327 int (*read_header)(struct AVFormatContext *,
328 AVFormatParameters *ap);
329 /** Read one packet and put it in 'pkt'. pts and flags are also
330 set. 'av_new_stream' can be called only if the flag
331 AVFMTCTX_NOHEADER is used. */
332 int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
333 /** Close the stream. The AVFormatContext and AVStreams are not
334 freed by this function */
335 int (*read_close)(struct AVFormatContext *);
336 /**
337 * Seek to a given timestamp relative to the frames in
338 * stream component stream_index.
339 * @param stream_index must not be -1
340 * @param flags selects which direction should be preferred if no exact
341 * match is available
342 * @return >= 0 on success (but not necessarily the new offset)
343 */
344 int (*read_seek)(struct AVFormatContext *,
345 int stream_index, int64_t timestamp, int flags);
346 /**
347 * Gets the next timestamp in stream[stream_index].time_base units.
348 * @return the timestamp or AV_NOPTS_VALUE if an error occurred
349 */
350 int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
351 int64_t *pos, int64_t pos_limit);
352 /** Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER. */
353 int flags;
354 /** If extensions are defined, then no probe is done. You should
355 usually not use extension format guessing because it is not
356 reliable enough */
357 const char *extensions;
358 /** General purpose read-only value that the format can use. */
359 int value;
360
361 /** Start/resume playing - only meaningful if using a network-based format
362 (RTSP). */
363 int (*read_play)(struct AVFormatContext *);
364
365 /** Pause playing - only meaningful if using a network-based format
366 (RTSP). */
367 int (*read_pause)(struct AVFormatContext *);
368
369 const struct AVCodecTag * const *codec_tag;
370
371 /* private fields */
372 struct AVInputFormat *next;
373 } AVInputFormat;
374
375 enum AVStreamParseType {
376 AVSTREAM_PARSE_NONE,
377 AVSTREAM_PARSE_FULL, /**< full parsing and repack */
378 AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
379 AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
380 };
381
382 typedef struct AVIndexEntry {
383 int64_t pos;
384 int64_t timestamp;
385 #define AVINDEX_KEYFRAME 0x0001
386 int flags:2;
387 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).
388 int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
389 } AVIndexEntry;
390
391 #define AV_DISPOSITION_DEFAULT 0x0001
392 #define AV_DISPOSITION_DUB 0x0002
393 #define AV_DISPOSITION_ORIGINAL 0x0004
394 #define AV_DISPOSITION_COMMENT 0x0008
395 #define AV_DISPOSITION_LYRICS 0x0010
396 #define AV_DISPOSITION_KARAOKE 0x0020
397
398 /**
399 * Stream structure.
400 * New fields can be added to the end with minor version bumps.
401 * Removal, reordering and changes to existing fields require a major
402 * version bump.
403 * sizeof(AVStream) must not be used outside libav*.
404 */
405 typedef struct AVStream {
406 int index; /**< stream index in AVFormatContext */
407 int id; /**< format-specific stream ID */
408 AVCodecContext *codec; /**< codec context */
409 /**
410 * Real base frame rate of the stream.
411 * This is the lowest frame rate with which all timestamps can be
412 * represented accurately (it is the least common multiple of all
413 * frame rates in the stream). Note, this value is just a guess!
414 * For example if the time base is 1/90000 and all frames have either
415 * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
416 */
417 AVRational r_frame_rate;
418 void *priv_data;
419
420 /* internal data used in av_find_stream_info() */
421 int64_t first_dts;
422 /** encoding: pts generation when outputting stream */
423 struct AVFrac pts;
424
425 /**
426 * This is the fundamental unit of time (in seconds) in terms
427 * of which frame timestamps are represented. For fixed-fps content,
428 * time base should be 1/frame rate and timestamp increments should be 1.
429 */
430 AVRational time_base;
431 int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
432 /* ffmpeg.c private use */
433 int stream_copy; /**< If set, just copy stream. */
434 enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
435 //FIXME move stuff to a flags field?
436 /** Quality, as it has been removed from AVCodecContext and put in AVVideoFrame.
437 * MN: dunno if that is the right place for it */
438 float quality;
439 /**
440 * Decoding: pts of the first frame of the stream, in stream time base.
441 * Only set this if you are absolutely 100% sure that the value you set
442 * it to really is the pts of the first frame.
443 * This may be undefined (AV_NOPTS_VALUE).
444 * @note The ASF header does NOT contain a correct start_time the ASF
445 * demuxer must NOT set this.
446 */
447 int64_t start_time;
448 /**
449 * Decoding: duration of the stream, in stream time base.
450 * If a source file does not specify a duration, but does specify
451 * a bitrate, this value will be estimated from bitrate and file size.
452 */
453 int64_t duration;
454
455 char language[4]; /** ISO 639 3-letter language code (empty string if undefined) */
456
457 /* av_read_frame() support */
458 enum AVStreamParseType need_parsing;
459 struct AVCodecParserContext *parser;
460
461 int64_t cur_dts;
462 int last_IP_duration;
463 int64_t last_IP_pts;
464 /* av_seek_frame() support */
465 AVIndexEntry *index_entries; /**< Only used if the format does not
466 support seeking natively. */
467 int nb_index_entries;
468 unsigned int index_entries_allocated_size;
469
470 int64_t nb_frames; ///< number of frames in this stream if known or 0
471
472 #if LIBAVFORMAT_VERSION_INT < (53<<16)
473 int64_t unused[4+1];
474 #endif
475
476 char *filename; /**< source filename of the stream */
477
478 int disposition; /**< AV_DISPOSITION_* bit field */
479
480 AVProbeData probe_data;
481 #define MAX_REORDER_DELAY 16
482 int64_t pts_buffer[MAX_REORDER_DELAY+1];
483
484 /**
485 * sample aspect ratio (0 if unknown)
486 * - encoding: Set by user.
487 * - decoding: Set by libavformat.
488 */
489 AVRational sample_aspect_ratio;
490
491 AVMetadata *metadata;
492
493 /* av_read_frame() support */
494 const uint8_t *cur_ptr;
495 int cur_len;
496 AVPacket cur_pkt;
497 } AVStream;
498
499 #define AV_PROGRAM_RUNNING 1
500
501 /**
502 * New fields can be added to the end with minor version bumps.
503 * Removal, reordering and changes to existing fields require a major
504 * version bump.
505 * sizeof(AVProgram) must not be used outside libav*.
506 */
507 typedef struct AVProgram {
508 int id;
509 char *provider_name; ///< network name for DVB streams
510 char *name; ///< service name for DVB streams
511 int flags;
512 enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
513 unsigned int *stream_index;
514 unsigned int nb_stream_indexes;
515 AVMetadata *metadata;
516 } AVProgram;
517
518 #define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
519 (streams are added dynamically) */
520
521 typedef struct AVChapter {
522 int id; ///< unique ID to identify the chapter
523 AVRational time_base; ///< time base in which the start/end timestamps are specified
524 int64_t start, end; ///< chapter start/end time in time_base units
525 char *title; ///< chapter title
526 AVMetadata *metadata;
527 } AVChapter;
528
529 #define MAX_STREAMS 20
530
531 /**
532 * Format I/O context.
533 * New fields can be added to the end with minor version bumps.
534 * Removal, reordering and changes to existing fields require a major
535 * version bump.
536 * sizeof(AVFormatContext) must not be used outside libav*.
537 */
538 typedef struct AVFormatContext {
539 const AVClass *av_class; /**< Set by av_alloc_format_context. */
540 /* Can only be iformat or oformat, not both at the same time. */
541 struct AVInputFormat *iformat;
542 struct AVOutputFormat *oformat;
543 void *priv_data;
544 ByteIOContext *pb;
545 unsigned int nb_streams;
546 AVStream *streams[MAX_STREAMS];
547 char filename[1024]; /**< input or output filename */
548 /* stream info */
549 int64_t timestamp;
550 char title[512];
551 char author[512];
552 char copyright[512];
553 char comment[512];
554 char album[512];
555 int year; /**< ID3 year, 0 if none */
556 int track; /**< track number, 0 if none */
557 char genre[32]; /**< ID3 genre */
558
559 int ctx_flags; /**< Format-specific flags, see AVFMTCTX_xx */
560 /* private data for pts handling (do not modify directly). */
561 /** This buffer is only needed when packets were already buffered but
562 not decoded, for example to get the codec parameters in MPEG
563 streams. */
564 struct AVPacketList *packet_buffer;
565
566 /** Decoding: position of the first frame of the component, in
567 AV_TIME_BASE fractional seconds. NEVER set this value directly:
568 It is deduced from the AVStream values. */
569 int64_t start_time;
570 /** Decoding: duration of the stream, in AV_TIME_BASE fractional
571 seconds. NEVER set this value directly: it is deduced from the
572 AVStream values. */
573 int64_t duration;
574 /** decoding: total file size, 0 if unknown */
575 int64_t file_size;
576 /** Decoding: total stream bitrate in bit/s, 0 if not
577 available. Never set it directly if the file_size and the
578 duration are known as ffmpeg can compute it automatically. */
579 int bit_rate;
580
581 /* av_read_frame() support */
582 AVStream *cur_st;
583 #if LIBAVFORMAT_VERSION_INT < (53<<16)
584 const uint8_t *cur_ptr_deprecated;
585 int cur_len_deprecated;
586 AVPacket cur_pkt_deprecated;
587 #endif
588
589 /* av_seek_frame() support */
590 int64_t data_offset; /** offset of the first packet */
591 int index_built;
592
593 int mux_rate;
594 int packet_size;
595 int preload;
596 int max_delay;
597
598 #define AVFMT_NOOUTPUTLOOP -1
599 #define AVFMT_INFINITEOUTPUTLOOP 0
600 /** number of times to loop output in formats that support it */
601 int loop_output;
602
603 int flags;
604 #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate pts if missing even if it requires parsing future frames.
605 #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
606 #define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
607
608 int loop_input;
609 /** Decoding: size of data to probe; encoding: unused. */
610 unsigned int probesize;
611
612 /**
613 * Maximum time (in AV_TIME_BASE units) during which the input should
614 * be analyzed in av_find_stream_info().
615 */
616 int max_analyze_duration;
617
618 const uint8_t *key;
619 int keylen;
620
621 unsigned int nb_programs;
622 AVProgram **programs;
623
624 /**
625 * Forced video codec_id.
626 * Demuxing: Set by user.
627 */
628 enum CodecID video_codec_id;
629 /**
630 * Forced audio codec_id.
631 * Demuxing: Set by user.
632 */
633 enum CodecID audio_codec_id;
634 /**
635 * Forced subtitle codec_id.
636 * Demuxing: Set by user.
637 */
638 enum CodecID subtitle_codec_id;
639
640 /**
641 * Maximum amount of memory in bytes to use per stream for the index.
642 * If the needed index exceeds this size, entries will be discarded as
643 * needed to maintain a smaller size. This can lead to slower or less
644 * accurate seeking (depends on demuxer).
645 * Demuxers for which a full in-memory index is mandatory will ignore
646 * this.
647 * muxing : unused
648 * demuxing: set by user
649 */
650 unsigned int max_index_size;
651
652 /**
653 * Maximum amount of memory in bytes to use for buffering frames
654 * obtained from realtime capture devices.
655 */
656 unsigned int max_picture_buffer;
657
658 unsigned int nb_chapters;
659 AVChapter **chapters;
660
661 /**
662 * Flags to enable debugging.
663 */
664 int debug;
665 #define FF_FDEBUG_TS 0x0001
666
667 /**
668 * Raw packets from the demuxer, prior to parsing and decoding.
669 * This buffer is used for buffering packets until the codec can
670 * be identified, as parsing cannot be done without knowing the
671 * codec.
672 */
673 struct AVPacketList *raw_packet_buffer;
674 struct AVPacketList *raw_packet_buffer_end;
675
676 struct AVPacketList *packet_buffer_end;
677
678 AVMetadata *metadata;
679 } AVFormatContext;
680
681 typedef struct AVPacketList {
682 AVPacket pkt;
683 struct AVPacketList *next;
684 } AVPacketList;
685
686 #if LIBAVFORMAT_VERSION_INT < (53<<16)
687 extern AVInputFormat *first_iformat;
688 extern AVOutputFormat *first_oformat;
689 #endif
690
691 AVInputFormat *av_iformat_next(AVInputFormat *f);
692 AVOutputFormat *av_oformat_next(AVOutputFormat *f);
693
694 enum CodecID av_guess_image2_codec(const char *filename);
695
696 /* XXX: use automatic init with either ELF sections or C file parser */
697 /* modules */
698
699 /* utils.c */
700 void av_register_input_format(AVInputFormat *format);
701 void av_register_output_format(AVOutputFormat *format);
702 AVOutputFormat *guess_stream_format(const char *short_name,
703 const char *filename,
704 const char *mime_type);
705 AVOutputFormat *guess_format(const char *short_name,
706 const char *filename,
707 const char *mime_type);
708
709 /**
710 * Guesses the codec ID based upon muxer and filename.
711 */
712 enum CodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
713 const char *filename, const char *mime_type,
714 enum CodecType type);
715
716 /**
717 * Send a nice hexadecimal dump of a buffer to the specified file stream.
718 *
719 * @param f The file stream pointer where the dump should be sent to.
720 * @param buf buffer
721 * @param size buffer size
722 *
723 * @see av_hex_dump_log, av_pkt_dump, av_pkt_dump_log
724 */
725 void av_hex_dump(FILE *f, uint8_t *buf, int size);
726
727 /**
728 * Send a nice hexadecimal dump of a buffer to the log.
729 *
730 * @param avcl A pointer to an arbitrary struct of which the first field is a
731 * pointer to an AVClass struct.
732 * @param level The importance level of the message, lower values signifying
733 * higher importance.
734 * @param buf buffer
735 * @param size buffer size
736 *
737 * @see av_hex_dump, av_pkt_dump, av_pkt_dump_log
738 */
739 void av_hex_dump_log(void *avcl, int level, uint8_t *buf, int size);
740
741 /**
742 * Send a nice dump of a packet to the specified file stream.
743 *
744 * @param f The file stream pointer where the dump should be sent to.
745 * @param pkt packet to dump
746 * @param dump_payload True if the payload must be displayed, too.
747 */
748 void av_pkt_dump(FILE *f, AVPacket *pkt, int dump_payload);
749
750 /**
751 * Send a nice dump of a packet to the log.
752 *
753 * @param avcl A pointer to an arbitrary struct of which the first field is a
754 * pointer to an AVClass struct.
755 * @param level The importance level of the message, lower values signifying
756 * higher importance.
757 * @param pkt packet to dump
758 * @param dump_payload True if the payload must be displayed, too.
759 */
760 void av_pkt_dump_log(void *avcl, int level, AVPacket *pkt, int dump_payload);
761
762 /**
763 * Initialize libavformat and register all the muxers, demuxers and
764 * protocols. If you do not call this function, then you can select
765 * exactly which formats you want to support.
766 *
767 * @see av_register_input_format()
768 * @see av_register_output_format()
769 * @see register_protocol()
770 */
771 void av_register_all(void);
772
773 /** codec tag <-> codec id */
774 enum CodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
775 unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum CodecID id);
776
777 /* media file input */
778
779 /**
780 * Finds AVInputFormat based on the short name of the input format.
781 */
782 AVInputFormat *av_find_input_format(const char *short_name);
783
784 /**
785 * Guess file format.
786 *
787 * @param is_opened Whether the file is already opened; determines whether
788 * demuxers with or without AVFMT_NOFILE are probed.
789 */
790 AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
791
792 /**
793 * Allocates all the structures needed to read an input stream.
794 * This does not open the needed codecs for decoding the stream[s].
795 */
796 int av_open_input_stream(AVFormatContext **ic_ptr,
797 ByteIOContext *pb, const char *filename,
798 AVInputFormat *fmt, AVFormatParameters *ap);
799
800 /**
801 * Open a media file as input. The codecs are not opened. Only the file
802 * header (if present) is read.
803 *
804 * @param ic_ptr The opened media file handle is put here.
805 * @param filename filename to open
806 * @param fmt If non-NULL, force the file format to use.
807 * @param buf_size optional buffer size (zero if default is OK)
808 * @param ap Additional parameters needed when opening the file
809 * (NULL if default).
810 * @return 0 if OK, AVERROR_xxx otherwise
811 */
812 int av_open_input_file(AVFormatContext **ic_ptr, const char *filename,
813 AVInputFormat *fmt,
814 int buf_size,
815 AVFormatParameters *ap);
816
817 #if LIBAVFORMAT_VERSION_MAJOR < 53
818 /**
819 * @deprecated Use avformat_alloc_context() instead.
820 */
821 attribute_deprecated AVFormatContext *av_alloc_format_context(void);
822 #endif
823
824 /**
825 * Allocate an AVFormatContext.
826 * Can be freed with av_free() but do not forget to free everything you
827 * explicitly allocated as well!
828 */
829 AVFormatContext *avformat_alloc_context(void);
830
831 /**
832 * Read packets of a media file to get stream information. This
833 * is useful for file formats with no headers such as MPEG. This
834 * function also computes the real frame rate in case of MPEG-2 repeat
835 * frame mode.
836 * The logical file position is not changed by this function;
837 * examined packets may be buffered for later processing.
838 *
839 * @param ic media file handle
840 * @return >=0 if OK, AVERROR_xxx on error
841 * @todo Let the user decide somehow what information is needed so that
842 * we do not waste time getting stuff the user does not need.
843 */
844 int av_find_stream_info(AVFormatContext *ic);
845
846 /**
847 * Read a transport packet from a media file.
848 *
849 * This function is obsolete and should never be used.
850 * Use av_read_frame() instead.
851 *
852 * @param s media file handle
853 * @param pkt is filled
854 * @return 0 if OK, AVERROR_xxx on error
855 */
856 int av_read_packet(AVFormatContext *s, AVPacket *pkt);
857
858 /**
859 * Return the next frame of a stream.
860 *
861 * The returned packet is valid
862 * until the next av_read_frame() or until av_close_input_file() and
863 * must be freed with av_free_packet. For video, the packet contains
864 * exactly one frame. For audio, it contains an integer number of
865 * frames if each frame has a known fixed size (e.g. PCM or ADPCM
866 * data). If the audio frames have a variable size (e.g. MPEG audio),
867 * then it contains one frame.
868 *
869 * pkt->pts, pkt->dts and pkt->duration are always set to correct
870 * values in AVStream.timebase units (and guessed if the format cannot
871 * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
872 * has B-frames, so it is better to rely on pkt->dts if you do not
873 * decompress the payload.
874 *
875 * @return 0 if OK, < 0 on error or end of file
876 */
877 int av_read_frame(AVFormatContext *s, AVPacket *pkt);
878
879 /**
880 * Seek to the key frame at timestamp.
881 * 'timestamp' in 'stream_index'.
882 * @param stream_index If stream_index is (-1), a default
883 * stream is selected, and timestamp is automatically converted
884 * from AV_TIME_BASE units to the stream specific time_base.
885 * @param timestamp Timestamp in AVStream.time_base units
886 * or, if no stream is specified, in AV_TIME_BASE units.
887 * @param flags flags which select direction and seeking mode
888 * @return >= 0 on success
889 */
890 int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
891 int flags);
892
893 /**
894 * Start playing a network based stream (e.g. RTSP stream) at the
895 * current position.
896 */
897 int av_read_play(AVFormatContext *s);
898
899 /**
900 * Pause a network based stream (e.g. RTSP stream).
901 *
902 * Use av_read_play() to resume it.
903 */
904 int av_read_pause(AVFormatContext *s);
905
906 /**
907 * Free a AVFormatContext allocated by av_open_input_stream.
908 * @param s context to free
909 */
910 void av_close_input_stream(AVFormatContext *s);
911
912 /**
913 * Close a media file (but not its codecs).
914 *
915 * @param s media file handle
916 */
917 void av_close_input_file(AVFormatContext *s);
918
919 /**
920 * Add a new stream to a media file.
921 *
922 * Can only be called in the read_header() function. If the flag
923 * AVFMTCTX_NOHEADER is in the format context, then new streams
924 * can be added in read_packet too.
925 *
926 * @param s media file handle
927 * @param id file-format-dependent stream ID
928 */
929 AVStream *av_new_stream(AVFormatContext *s, int id);
930 AVProgram *av_new_program(AVFormatContext *s, int id);
931
932 /**
933 * Add a new chapter.
934 * This function is NOT part of the public API
935 * and should ONLY be used by demuxers.
936 *
937 * @param s media file handle
938 * @param id unique ID for this chapter
939 * @param start chapter start time in time_base units
940 * @param end chapter end time in time_base units
941 * @param title chapter title
942 *
943 * @return AVChapter or NULL on error
944 */
945 AVChapter *ff_new_chapter(AVFormatContext *s, int id, AVRational time_base,
946 int64_t start, int64_t end, const char *title);
947
948 /**
949 * Set the pts for a given stream.
950 *
951 * @param s stream
952 * @param pts_wrap_bits number of bits effectively used by the pts
953 * (used for wrap control, 33 is the value for MPEG)
954 * @param pts_num numerator to convert to seconds (MPEG: 1)
955 * @param pts_den denominator to convert to seconds (MPEG: 90000)
956 */
957 void av_set_pts_info(AVStream *s, int pts_wrap_bits,
958 int pts_num, int pts_den);
959
960 #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
961 #define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
962 #define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
963
964 int av_find_default_stream_index(AVFormatContext *s);
965
966 /**
967 * Gets the index for a specific timestamp.
968 * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
969 * to the timestamp which is <= the requested one, if backward
970 * is 0, then it will be >=
971 * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
972 * @return < 0 if no such timestamp could be found
973 */
974 int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
975
976 /**
977 * Ensures the index uses less memory than the maximum specified in
978 * AVFormatContext.max_index_size, by discarding entries if it grows
979 * too large.
980 * This function is not part of the public API and should only be called
981 * by demuxers.
982 */
983 void ff_reduce_index(AVFormatContext *s, int stream_index);
984
985 /**
986 * Add an index entry into a sorted list. Update the entry if the list
987 * already contains it.
988 *
989 * @param timestamp timestamp in the time base of the given stream
990 */
991 int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
992 int size, int distance, int flags);
993
994 /**
995 * Does a binary search using av_index_search_timestamp() and
996 * AVCodec.read_timestamp().
997 * This is not supposed to be called directly by a user application,
998 * but by demuxers.
999 * @param target_ts target timestamp in the time base of the given stream
1000 * @param stream_index stream number
1001 */
1002 int av_seek_frame_binary(AVFormatContext *s, int stream_index,
1003 int64_t target_ts, int flags);
1004
1005 /**
1006 * Updates cur_dts of all streams based on the given timestamp and AVStream.
1007 *
1008 * Stream ref_st unchanged, others set cur_dts in their native time base.
1009 * Only needed for timestamp wrapping or if (dts not set and pts!=dts).
1010 * @param timestamp new dts expressed in time_base of param ref_st
1011 * @param ref_st reference stream giving time_base of param timestamp
1012 */
1013 void av_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp);
1014
1015 /**
1016 * Does a binary search using read_timestamp().
1017 * This is not supposed to be called directly by a user application,
1018 * but by demuxers.
1019 * @param target_ts target timestamp in the time base of the given stream
1020 * @param stream_index stream number
1021 */
1022 int64_t av_gen_search(AVFormatContext *s, int stream_index,
1023 int64_t target_ts, int64_t pos_min,
1024 int64_t pos_max, int64_t pos_limit,
1025 int64_t ts_min, int64_t ts_max,
1026 int flags, int64_t *ts_ret,
1027 int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
1028
1029 /** media file output */
1030 int av_set_parameters(AVFormatContext *s, AVFormatParameters *ap);
1031
1032 /**
1033 * Allocate the stream private data and write the stream header to an
1034 * output media file.
1035 *
1036 * @param s media file handle
1037 * @return 0 if OK, AVERROR_xxx on error
1038 */
1039 int av_write_header(AVFormatContext *s);
1040
1041 /**
1042 * Write a packet to an output media file.
1043 *
1044 * The packet shall contain one audio or video frame.
1045 * The packet must be correctly interleaved according to the container
1046 * specification, if not then av_interleaved_write_frame must be used.
1047 *
1048 * @param s media file handle
1049 * @param pkt The packet, which contains the stream_index, buf/buf_size,
1050 dts/pts, ...
1051 * @return < 0 on error, = 0 if OK, 1 if end of stream wanted
1052 */
1053 int av_write_frame(AVFormatContext *s, AVPacket *pkt);
1054
1055 /**
1056 * Writes a packet to an output media file ensuring correct interleaving.
1057 *
1058 * The packet must contain one audio or video frame.
1059 * If the packets are already correctly interleaved the application should
1060 * call av_write_frame() instead as it is slightly faster. It is also important
1061 * to keep in mind that completely non-interleaved input will need huge amounts
1062 * of memory to interleave with this, so it is preferable to interleave at the
1063 * demuxer level.
1064 *
1065 * @param s media file handle
1066 * @param pkt The packet, which contains the stream_index, buf/buf_size,
1067 dts/pts, ...
1068 * @return < 0 on error, = 0 if OK, 1 if end of stream wanted
1069 */
1070 int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
1071
1072 /**
1073 * Interleave a packet per dts in an output media file.
1074 *
1075 * Packets with pkt->destruct == av_destruct_packet will be freed inside this
1076 * function, so they cannot be used after it, note calling av_free_packet()
1077 * on them is still safe.
1078 *
1079 * @param s media file handle
1080 * @param out the interleaved packet will be output here
1081 * @param in the input packet
1082 * @param flush 1 if no further packets are available as input and all
1083 * remaining packets should be output
1084 * @return 1 if a packet was output, 0 if no packet could be output,
1085 * < 0 if an error occurred
1086 */
1087 int av_interleave_packet_per_dts(AVFormatContext *s, AVPacket *out,
1088 AVPacket *pkt, int flush);
1089
1090 /**
1091 * Add packet to AVFormatContext->packet_buffer list, determining its
1092 * interleaved position using compare() function argument.
1093 *
1094 * This function is not part of the public API and should only be called
1095 * by muxers using their own interleave function.
1096 */
1097 void ff_interleave_add_packet(AVFormatContext *s, AVPacket *pkt,
1098 int (*compare)(AVFormatContext *, AVPacket *, AVPacket *));
1099
1100 /**
1101 * @brief Write the stream trailer to an output media file and
1102 * free the file private data.
1103 *
1104 * May only be called after a successful call to av_write_header.
1105 *
1106 * @param s media file handle
1107 * @return 0 if OK, AVERROR_xxx on error
1108 */
1109 int av_write_trailer(AVFormatContext *s);
1110
1111 void dump_format(AVFormatContext *ic,
1112 int index,
1113 const char *url,
1114 int is_output);
1115
1116 #if LIBAVFORMAT_VERSION_MAJOR < 53
1117 /**
1118 * Parses width and height out of string str.
1119 * @deprecated Use av_parse_video_frame_size instead.
1120 */
1121 attribute_deprecated int parse_image_size(int *width_ptr, int *height_ptr,
1122 const char *str);
1123
1124 /**
1125 * Converts frame rate from string to a fraction.
1126 * @deprecated Use av_parse_video_frame_rate instead.
1127 */
1128 attribute_deprecated int parse_frame_rate(int *frame_rate, int *frame_rate_base,
1129 const char *arg);
1130 #endif
1131
1132 /**
1133 * Parses \p datestr and returns a corresponding number of microseconds.
1134 * @param datestr String representing a date or a duration.
1135 * - If a date the syntax is:
1136 * @code
1137 * [{YYYY-MM-DD|YYYYMMDD}]{T| }{HH[:MM[:SS[.m...]]][Z]|HH[MM[SS[.m...]]][Z]}
1138 * @endcode
1139 * Time is local time unless Z is appended, in which case it is
1140 * interpreted as UTC.
1141 * If the year-month-day part is not specified it takes the current
1142 * year-month-day.
1143 * Returns the number of microseconds since 1st of January, 1970 up to
1144 * the time of the parsed date or INT64_MIN if \p datestr cannot be
1145 * successfully parsed.
1146 * - If a duration the syntax is:
1147 * @code
1148 * [-]HH[:MM[:SS[.m...]]]
1149 * [-]S+[.m...]
1150 * @endcode
1151 * Returns the number of microseconds contained in a time interval
1152 * with the specified duration or INT64_MIN if \p datestr cannot be
1153 * successfully parsed.
1154 * @param duration Flag which tells how to interpret \p datestr, if
1155 * not zero \p datestr is interpreted as a duration, otherwise as a
1156 * date.
1157 */
1158 int64_t parse_date(const char *datestr, int duration);
1159
1160 /** Gets the current time in microseconds. */
1161 int64_t av_gettime(void);
1162
1163 /* ffm-specific for ffserver */
1164 #define FFM_PACKET_SIZE 4096
1165 int64_t ffm_read_write_index(int fd);
1166 void ffm_write_write_index(int fd, int64_t pos);
1167 void ffm_set_write_index(AVFormatContext *s, int64_t pos, int64_t file_size);
1168
1169 /**
1170 * Attempts to find a specific tag in a URL.
1171 *
1172 * syntax: '?tag1=val1&tag2=val2...'. Little URL decoding is done.
1173 * Return 1 if found.
1174 */
1175 int find_info_tag(char *arg, int arg_size, const char *tag1, const char *info);
1176
1177 /**
1178 * Returns in 'buf' the path with '%d' replaced by number.
1179 *
1180 * Also handles the '%0nd' format where 'n' is the total number
1181 * of digits and '%%'.
1182 *
1183 * @param buf destination buffer
1184 * @param buf_size destination buffer size
1185 * @param path numbered sequence string
1186 * @param number frame number
1187 * @return 0 if OK, -1 on format error
1188 */
1189 int av_get_frame_filename(char *buf, int buf_size,
1190 const char *path, int number);
1191
1192 /**
1193 * Check whether filename actually is a numbered sequence generator.
1194 *
1195 * @param filename possible numbered sequence string
1196 * @return 1 if a valid numbered sequence string, 0 otherwise
1197 */
1198 int av_filename_number_test(const char *filename);
1199
1200 /**
1201 * Generate an SDP for an RTP session.
1202 *
1203 * @param ac array of AVFormatContexts describing the RTP streams. If the
1204 * array is composed by only one context, such context can contain
1205 * multiple AVStreams (one AVStream per RTP stream). Otherwise,
1206 * all the contexts in the array (an AVCodecContext per RTP stream)
1207 * must contain only one AVStream.
1208 * @param n_files number of AVCodecContexts contained in ac
1209 * @param buff buffer where the SDP will be stored (must be allocated by
1210 * the caller)
1211 * @param size the size of the buffer
1212 * @return 0 if OK, AVERROR_xxx on error
1213 */
1214 int avf_sdp_create(AVFormatContext *ac[], int n_files, char *buff, int size);
1215
1216 #ifdef HAVE_AV_CONFIG_H
1217
1218 void ff_dynarray_add(intptr_t **tab_ptr, int *nb_ptr, intptr_t elem);
1219
1220 #ifdef __GNUC__
1221 #define dynarray_add(tab, nb_ptr, elem)\
1222 do {\
1223 __typeof__(tab) _tab = (tab);\
1224 __typeof__(elem) _elem = (elem);\
1225 (void)sizeof(**_tab == _elem); /* check that types are compatible */\
1226 ff_dynarray_add((intptr_t **)_tab, nb_ptr, (intptr_t)_elem);\
1227 } while(0)
1228 #else
1229 #define dynarray_add(tab, nb_ptr, elem)\
1230 do {\
1231 ff_dynarray_add((intptr_t **)(tab), nb_ptr, (intptr_t)(elem));\
1232 } while(0)
1233 #endif
1234
1235 time_t mktimegm(struct tm *tm);
1236 struct tm *brktimegm(time_t secs, struct tm *tm);
1237 const char *small_strptime(const char *p, const char *fmt,
1238 struct tm *dt);
1239
1240 struct in_addr;
1241 int resolve_host(struct in_addr *sin_addr, const char *hostname);
1242
1243 void url_split(char *proto, int proto_size,
1244 char *authorization, int authorization_size,
1245 char *hostname, int hostname_size,
1246 int *port_ptr,
1247 char *path, int path_size,
1248 const char *url);
1249
1250 int match_ext(const char *filename, const char *extensions);
1251
1252 #endif /* HAVE_AV_CONFIG_H */
1253
1254 #endif /* AVFORMAT_AVFORMAT_H */