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_INTERNAL_H
22 #define AVFORMAT_INTERNAL_H
23
24 #include <stdint.h>
25
26 #include "libavcodec/avcodec.h"
27 #include "libavcodec/packet_internal.h"
28
29 #include "avformat.h"
30 #include "os_support.h"
31
32 #define MAX_URL_SIZE 4096
33
34 /** size of probe buffer, for guessing file type from file contents */
35 #define PROBE_BUF_MIN 2048
36 #define PROBE_BUF_MAX (1 << 20)
37
38 #ifdef DEBUG
39 # define hex_dump_debug(class, buf, size) av_hex_dump_log(class, AV_LOG_DEBUG, buf, size)
40 #else
41 # define hex_dump_debug(class, buf, size) do { if (0) av_hex_dump_log(class, AV_LOG_DEBUG, buf, size); } while(0)
42 #endif
43
44 /**
45 * For an AVInputFormat with this flag set read_close() needs to be called
46 * by the caller upon read_header() failure.
47 */
48 #define FF_FMT_INIT_CLEANUP (1 << 0)
49
50 typedef struct AVCodecTag {
51 enum AVCodecID id;
52 unsigned int tag;
53 } AVCodecTag;
54
55 typedef struct CodecMime{
56 char str[32];
57 enum AVCodecID id;
58 } CodecMime;
59
60 /*************************************************/
61 /* fractional numbers for exact pts handling */
62
63 /**
64 * The exact value of the fractional number is: 'val + num / den'.
65 * num is assumed to be 0 <= num < den.
66 */
67 typedef struct FFFrac {
68 int64_t val, num, den;
69 } FFFrac;
70
71
72 typedef struct FFFormatContext {
73 /**
74 * The public context.
75 */
76 AVFormatContext pub;
77
78 /**
79 * Number of streams relevant for interleaving.
80 * Muxing only.
81 */
82 int nb_interleaved_streams;
83
84 /**
85 * Whether the timestamp shift offset has already been determined.
86 * -1: disabled, 0: not yet determined, 1: determined.
87 */
88 enum {
89 AVOID_NEGATIVE_TS_DISABLED = -1,
90 AVOID_NEGATIVE_TS_UNKNOWN = 0,
91 AVOID_NEGATIVE_TS_KNOWN = 1,
92 } avoid_negative_ts_status;
93 #define AVOID_NEGATIVE_TS_ENABLED(status) ((status) >= 0)
94
95 /**
96 * The interleavement function in use. Always set for muxers.
97 */
98 int (*interleave_packet)(struct AVFormatContext *s, AVPacket *pkt,
99 int flush, int has_packet);
100
101 /**
102 * This buffer is only needed when packets were already buffered but
103 * not decoded, for example to get the codec parameters in MPEG
104 * streams.
105 */
106 PacketList packet_buffer;
107
108 /* av_seek_frame() support */
109 int64_t data_offset; /**< offset of the first packet */
110
111 /**
112 * Raw packets from the demuxer, prior to parsing and decoding.
113 * This buffer is used for buffering packets until the codec can
114 * be identified, as parsing cannot be done without knowing the
115 * codec.
116 */
117 PacketList raw_packet_buffer;
118 /**
119 * Packets split by the parser get queued here.
120 */
121 PacketList parse_queue;
122 /**
123 * The generic code uses this as a temporary packet
124 * to parse packets or for muxing, especially flushing.
125 * For demuxers, it may also be used for other means
126 * for short periods that are guaranteed not to overlap
127 * with calls to av_read_frame() (or ff_read_packet())
128 * or with each other.
129 * It may be used by demuxers as a replacement for
130 * stack packets (unless they call one of the aforementioned
131 * functions with their own AVFormatContext).
132 * Every user has to ensure that this packet is blank
133 * after using it.
134 */
135 AVPacket *parse_pkt;
136
137 /**
138 * Used to hold temporary packets for the generic demuxing code.
139 * When muxing, it may be used by muxers to hold packets (even
140 * permanent ones).
141 */
142 AVPacket *pkt;
143 /**
144 * Sum of the size of packets in raw_packet_buffer, in bytes.
145 */
146 int raw_packet_buffer_size;
147
148 #if FF_API_COMPUTE_PKT_FIELDS2
149 int missing_ts_warning;
150 #endif
151
152 int inject_global_side_data;
153
154 int avoid_negative_ts_use_pts;
155
156 /**
157 * Timestamp of the end of the shortest stream.
158 */
159 int64_t shortest_end;
160
161 /**
162 * Whether or not avformat_init_output has already been called
163 */
164 int initialized;
165
166 /**
167 * Whether or not avformat_init_output fully initialized streams
168 */
169 int streams_initialized;
170
171 /**
172 * ID3v2 tag useful for MP3 demuxing
173 */
174 AVDictionary *id3v2_meta;
175
176 /*
177 * Prefer the codec framerate for avg_frame_rate computation.
178 */
179 int prefer_codec_framerate;
180
181 /**
182 * Set if chapter ids are strictly monotonic.
183 */
184 int chapter_ids_monotonic;
185
186 /**
187 * Contexts and child contexts do not contain a metadata option
188 */
189 int metafree;
190 } FFFormatContext;
191
ffformatcontext(AVFormatContext * s)192 static av_always_inline FFFormatContext *ffformatcontext(AVFormatContext *s)
193 {
194 return (FFFormatContext*)s;
195 }
196
197 typedef struct FFStream {
198 /**
199 * The public context.
200 */
201 AVStream pub;
202
203 /**
204 * Set to 1 if the codec allows reordering, so pts can be different
205 * from dts.
206 */
207 int reorder;
208
209 /**
210 * bitstream filter to run on stream
211 * - encoding: Set by muxer using ff_stream_add_bitstream_filter
212 * - decoding: unused
213 */
214 struct AVBSFContext *bsfc;
215
216 /**
217 * Whether or not check_bitstream should still be run on each packet
218 */
219 int bitstream_checked;
220
221 /**
222 * The codec context used by avformat_find_stream_info, the parser, etc.
223 */
224 AVCodecContext *avctx;
225 /**
226 * 1 if avctx has been initialized with the values from the codec parameters
227 */
228 int avctx_inited;
229
230 /* the context for extracting extradata in find_stream_info()
231 * inited=1/bsf=NULL signals that extracting is not possible (codec not
232 * supported) */
233 struct {
234 struct AVBSFContext *bsf;
235 int inited;
236 } extract_extradata;
237
238 /**
239 * Whether the internal avctx needs to be updated from codecpar (after a late change to codecpar)
240 */
241 int need_context_update;
242
243 int is_intra_only;
244
245 FFFrac *priv_pts;
246
247 /**
248 * Stream information used internally by avformat_find_stream_info()
249 */
250 struct FFStreamInfo *info;
251
252 AVIndexEntry *index_entries; /**< Only used if the format does not
253 support seeking natively. */
254 int nb_index_entries;
255 unsigned int index_entries_allocated_size;
256
257 int64_t interleaver_chunk_size;
258 int64_t interleaver_chunk_duration;
259
260 /**
261 * stream probing state
262 * -1 -> probing finished
263 * 0 -> no probing requested
264 * rest -> perform probing with request_probe being the minimum score to accept.
265 */
266 int request_probe;
267 /**
268 * Indicates that everything up to the next keyframe
269 * should be discarded.
270 */
271 int skip_to_keyframe;
272
273 /**
274 * Number of samples to skip at the start of the frame decoded from the next packet.
275 */
276 int skip_samples;
277
278 /**
279 * If not 0, the number of samples that should be skipped from the start of
280 * the stream (the samples are removed from packets with pts==0, which also
281 * assumes negative timestamps do not happen).
282 * Intended for use with formats such as mp3 with ad-hoc gapless audio
283 * support.
284 */
285 int64_t start_skip_samples;
286
287 /**
288 * If not 0, the first audio sample that should be discarded from the stream.
289 * This is broken by design (needs global sample count), but can't be
290 * avoided for broken by design formats such as mp3 with ad-hoc gapless
291 * audio support.
292 */
293 int64_t first_discard_sample;
294
295 /**
296 * The sample after last sample that is intended to be discarded after
297 * first_discard_sample. Works on frame boundaries only. Used to prevent
298 * early EOF if the gapless info is broken (considered concatenated mp3s).
299 */
300 int64_t last_discard_sample;
301
302 /**
303 * Number of internally decoded frames, used internally in libavformat, do not access
304 * its lifetime differs from info which is why it is not in that structure.
305 */
306 int nb_decoded_frames;
307
308 /**
309 * Timestamp offset added to timestamps before muxing
310 */
311 int64_t mux_ts_offset;
312
313 /**
314 * Internal data to check for wrapping of the time stamp
315 */
316 int64_t pts_wrap_reference;
317
318 /**
319 * Options for behavior, when a wrap is detected.
320 *
321 * Defined by AV_PTS_WRAP_ values.
322 *
323 * If correction is enabled, there are two possibilities:
324 * If the first time stamp is near the wrap point, the wrap offset
325 * will be subtracted, which will create negative time stamps.
326 * Otherwise the offset will be added.
327 */
328 int pts_wrap_behavior;
329
330 /**
331 * Internal data to prevent doing update_initial_durations() twice
332 */
333 int update_initial_durations_done;
334
335 #define MAX_REORDER_DELAY 16
336
337 /**
338 * Internal data to generate dts from pts
339 */
340 int64_t pts_reorder_error[MAX_REORDER_DELAY+1];
341 uint8_t pts_reorder_error_count[MAX_REORDER_DELAY+1];
342
343 int64_t pts_buffer[MAX_REORDER_DELAY+1];
344
345 /**
346 * Internal data to analyze DTS and detect faulty mpeg streams
347 */
348 int64_t last_dts_for_order_check;
349 uint8_t dts_ordered;
350 uint8_t dts_misordered;
351
352 /**
353 * Internal data to inject global side data
354 */
355 int inject_global_side_data;
356
357 /**
358 * display aspect ratio (0 if unknown)
359 * - encoding: unused
360 * - decoding: Set by libavformat to calculate sample_aspect_ratio internally
361 */
362 AVRational display_aspect_ratio;
363
364 AVProbeData probe_data;
365
366 /**
367 * last packet in packet_buffer for this stream when muxing.
368 */
369 PacketListEntry *last_in_packet_buffer;
370
371 int64_t last_IP_pts;
372 int last_IP_duration;
373
374 /**
375 * Number of packets to buffer for codec probing
376 */
377 int probe_packets;
378
379 /* av_read_frame() support */
380 enum AVStreamParseType need_parsing;
381 struct AVCodecParserContext *parser;
382
383 /**
384 * Number of frames that have been demuxed during avformat_find_stream_info()
385 */
386 int codec_info_nb_frames;
387
388 /**
389 * Stream Identifier
390 * This is the MPEG-TS stream identifier +1
391 * 0 means unknown
392 */
393 int stream_identifier;
394
395 // Timestamp generation support:
396 /**
397 * Timestamp corresponding to the last dts sync point.
398 *
399 * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
400 * a DTS is received from the underlying container. Otherwise set to
401 * AV_NOPTS_VALUE by default.
402 */
403 int64_t first_dts;
404 int64_t cur_dts;
405 } FFStream;
406
ffstream(AVStream * st)407 static av_always_inline FFStream *ffstream(AVStream *st)
408 {
409 return (FFStream*)st;
410 }
411
cffstream(const AVStream * st)412 static av_always_inline const FFStream *cffstream(const AVStream *st)
413 {
414 return (FFStream*)st;
415 }
416
417 #ifdef __GNUC__
418 #define dynarray_add(tab, nb_ptr, elem)\
419 do {\
420 __typeof__(tab) _tab = (tab);\
421 __typeof__(elem) _elem = (elem);\
422 (void)sizeof(**_tab == _elem); /* check that types are compatible */\
423 av_dynarray_add(_tab, nb_ptr, _elem);\
424 } while(0)
425 #else
426 #define dynarray_add(tab, nb_ptr, elem)\
427 do {\
428 av_dynarray_add((tab), nb_ptr, (elem));\
429 } while(0)
430 #endif
431
432
433 void ff_flush_packet_queue(AVFormatContext *s);
434
435 /**
436 * Automatically create sub-directories
437 *
438 * @param path will create sub-directories by path
439 * @return 0, or < 0 on error
440 */
441 int ff_mkdir_p(const char *path);
442
443 /**
444 * Write hexadecimal string corresponding to given binary data. The string
445 * is zero-terminated.
446 *
447 * @param buf the output string is written here;
448 * needs to be at least 2 * size + 1 bytes long.
449 * @param src the input data to be transformed.
450 * @param size the size (in byte) of src.
451 * @param lowercase determines whether to use the range [0-9a-f] or [0-9A-F].
452 * @return buf.
453 */
454 char *ff_data_to_hex(char *buf, const uint8_t *src, int size, int lowercase);
455
456 /**
457 * Parse a string of hexadecimal strings. Any space between the hexadecimal
458 * digits is ignored.
459 *
460 * @param data if non-null, the parsed data is written to this pointer
461 * @param p the string to parse
462 * @return the number of bytes written (or to be written, if data is null)
463 */
464 int ff_hex_to_data(uint8_t *data, const char *p);
465
466 #define NTP_OFFSET 2208988800ULL
467 #define NTP_OFFSET_US (NTP_OFFSET * 1000000ULL)
468
469 /** Get the current time since NTP epoch in microseconds. */
470 uint64_t ff_ntp_time(void);
471
472 /**
473 * Get the NTP time stamp formatted as per the RFC-5905.
474 *
475 * @param ntp_time NTP time in micro seconds (since NTP epoch)
476 * @return the formatted NTP time stamp
477 */
478 uint64_t ff_get_formatted_ntp_time(uint64_t ntp_time_us);
479
480 /**
481 * Parse the NTP time in micro seconds (since NTP epoch).
482 *
483 * @param ntp_ts NTP time stamp formatted as per the RFC-5905.
484 * @return the time in micro seconds (since NTP epoch)
485 */
486 uint64_t ff_parse_ntp_time(uint64_t ntp_ts);
487
488 /**
489 * Append the media-specific SDP fragment for the media stream c
490 * to the buffer buff.
491 *
492 * Note, the buffer needs to be initialized, since it is appended to
493 * existing content.
494 *
495 * @param buff the buffer to append the SDP fragment to
496 * @param size the size of the buff buffer
497 * @param st the AVStream of the media to describe
498 * @param idx the global stream index
499 * @param dest_addr the destination address of the media stream, may be NULL
500 * @param dest_type the destination address type, may be NULL
501 * @param port the destination port of the media stream, 0 if unknown
502 * @param ttl the time to live of the stream, 0 if not multicast
503 * @param fmt the AVFormatContext, which might contain options modifying
504 * the generated SDP
505 * @return 0 on success, a negative error code on failure
506 */
507 int ff_sdp_write_media(char *buff, int size, const AVStream *st, int idx,
508 const char *dest_addr, const char *dest_type,
509 int port, int ttl, AVFormatContext *fmt);
510
511 /**
512 * Read a whole line of text from AVIOContext. Stop reading after reaching
513 * either a \\n, a \\0 or EOF. The returned string is always \\0-terminated,
514 * and may be truncated if the buffer is too small.
515 *
516 * @param s the read-only AVIOContext
517 * @param buf buffer to store the read line
518 * @param maxlen size of the buffer
519 * @return the length of the string written in the buffer, not including the
520 * final \\0
521 */
522 int ff_get_line(AVIOContext *s, char *buf, int maxlen);
523
524 /**
525 * Same as ff_get_line but strip the white-space characters in the text tail
526 *
527 * @param s the read-only AVIOContext
528 * @param buf buffer to store the read line
529 * @param maxlen size of the buffer
530 * @return the length of the string written in the buffer
531 */
532 int ff_get_chomp_line(AVIOContext *s, char *buf, int maxlen);
533
534 #define SPACE_CHARS " \t\r\n"
535
536 /**
537 * Callback function type for ff_parse_key_value.
538 *
539 * @param key a pointer to the key
540 * @param key_len the number of bytes that belong to the key, including the '='
541 * char
542 * @param dest return the destination pointer for the value in *dest, may
543 * be null to ignore the value
544 * @param dest_len the length of the *dest buffer
545 */
546 typedef void (*ff_parse_key_val_cb)(void *context, const char *key,
547 int key_len, char **dest, int *dest_len);
548 /**
549 * Parse a string with comma-separated key=value pairs. The value strings
550 * may be quoted and may contain escaped characters within quoted strings.
551 *
552 * @param str the string to parse
553 * @param callback_get_buf function that returns where to store the
554 * unescaped value string.
555 * @param context the opaque context pointer to pass to callback_get_buf
556 */
557 void ff_parse_key_value(const char *str, ff_parse_key_val_cb callback_get_buf,
558 void *context);
559
560 enum AVCodecID ff_guess_image2_codec(const char *filename);
561
562 const AVCodec *ff_find_decoder(AVFormatContext *s, const AVStream *st,
563 enum AVCodecID codec_id);
564
565 /**
566 * Set the time base and wrapping info for a given stream. This will be used
567 * to interpret the stream's timestamps. If the new time base is invalid
568 * (numerator or denominator are non-positive), it leaves the stream
569 * unchanged.
570 *
571 * @param st stream
572 * @param pts_wrap_bits number of bits effectively used by the pts
573 * (used for wrap control)
574 * @param pts_num time base numerator
575 * @param pts_den time base denominator
576 */
577 void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits,
578 unsigned int pts_num, unsigned int pts_den);
579
580 /**
581 * Set the timebase for each stream from the corresponding codec timebase and
582 * print it.
583 */
584 int ff_framehash_write_header(AVFormatContext *s);
585
586 /**
587 * Frees a stream without modifying the corresponding AVFormatContext.
588 * Must only be called if the latter doesn't matter or if the stream
589 * is not yet attached to an AVFormatContext.
590 */
591 void ff_free_stream(AVStream **st);
592 /**
593 * Remove a stream from its AVFormatContext and free it.
594 * The stream must be the last stream of the AVFormatContext.
595 */
596 void ff_remove_stream(AVFormatContext *s, AVStream *st);
597
598 unsigned int ff_codec_get_tag(const AVCodecTag *tags, enum AVCodecID id);
599
600 enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag);
601
602 int ff_is_intra_only(enum AVCodecID id);
603
604 /**
605 * Select a PCM codec based on the given parameters.
606 *
607 * @param bps bits-per-sample
608 * @param flt floating-point
609 * @param be big-endian
610 * @param sflags signed flags. each bit corresponds to one byte of bit depth.
611 * e.g. the 1st bit indicates if 8-bit should be signed or
612 * unsigned, the 2nd bit indicates if 16-bit should be signed or
613 * unsigned, etc... This is useful for formats such as WAVE where
614 * only 8-bit is unsigned and all other bit depths are signed.
615 * @return a PCM codec id or AV_CODEC_ID_NONE
616 */
617 enum AVCodecID ff_get_pcm_codec_id(int bps, int flt, int be, int sflags);
618
619 /**
620 * Copy side data from source to destination stream
621 *
622 * @param dst pointer to destination AVStream
623 * @param src pointer to source AVStream
624 * @return >=0 on success, AVERROR code on error
625 */
626 int ff_stream_side_data_copy(AVStream *dst, const AVStream *src);
627
628 /**
629 * Wrap ffurl_move() and log if error happens.
630 *
631 * @param url_src source path
632 * @param url_dst destination path
633 * @return 0 or AVERROR on failure
634 */
635 int ff_rename(const char *url_src, const char *url_dst, void *logctx);
636
637 /**
638 * Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end
639 * which is always set to 0.
640 *
641 * Previously allocated extradata in par will be freed.
642 *
643 * @param size size of extradata
644 * @return 0 if OK, AVERROR_xxx on error
645 */
646 int ff_alloc_extradata(AVCodecParameters *par, int size);
647
648 /**
649 * Copies the whilelists from one context to the other
650 */
651 int ff_copy_whiteblacklists(AVFormatContext *dst, const AVFormatContext *src);
652
653 /*
654 * A wrapper around AVFormatContext.io_close that should be used
655 * instead of calling the pointer directly.
656 *
657 * @param s AVFormatContext
658 * @param *pb the AVIOContext to be closed and freed. Can be NULL.
659 * @return >=0 on success, negative AVERROR in case of failure
660 */
661 int ff_format_io_close(AVFormatContext *s, AVIOContext **pb);
662
663 /* Default io_close callback, not to be used directly, use ff_format_io_close
664 * instead. */
665 void ff_format_io_close_default(AVFormatContext *s, AVIOContext *pb);
666
667 /**
668 * Utility function to check if the file uses http or https protocol
669 *
670 * @param s AVFormatContext
671 * @param filename URL or file name to open for writing
672 */
673 int ff_is_http_proto(const char *filename);
674
675 struct AVBPrint;
676 /**
677 * Finalize buf into extradata and set its size appropriately.
678 */
679 int ff_bprint_to_codecpar_extradata(AVCodecParameters *par, struct AVBPrint *buf);
680
681 int ff_lock_avformat(void);
682 int ff_unlock_avformat(void);
683
684 /**
685 * Set AVFormatContext url field to the provided pointer. The pointer must
686 * point to a valid string. The existing url field is freed if necessary. Also
687 * set the legacy filename field to the same string which was provided in url.
688 */
689 void ff_format_set_url(AVFormatContext *s, char *url);
690
691 void avpriv_register_devices(const AVOutputFormat * const o[], const AVInputFormat * const i[]);
692
693 #endif /* AVFORMAT_INTERNAL_H */
694