2 * copyright (c) 2001 Fabrice Bellard
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 #ifndef AVFORMAT_INTERNAL_H
22 #define AVFORMAT_INTERNAL_H
26 #include "libavutil/bprint.h"
28 #include "os_support.h"
30 #define MAX_URL_SIZE 4096
32 /** size of probe buffer, for guessing file type from file contents */
33 #define PROBE_BUF_MIN 2048
34 #define PROBE_BUF_MAX (1 << 20)
37 # define hex_dump_debug(class, buf, size) av_hex_dump_log(class, AV_LOG_DEBUG, buf, size)
39 # define hex_dump_debug(class, buf, size) do { if (0) av_hex_dump_log(class, AV_LOG_DEBUG, buf, size); } while(0)
42 typedef struct AVCodecTag {
47 typedef struct CodecMime{
52 /*************************************************/
53 /* fractional numbers for exact pts handling */
56 * The exact value of the fractional number is: 'val + num / den'.
57 * num is assumed to be 0 <= num < den.
59 typedef struct FFFrac {
60 int64_t val, num, den;
64 struct AVFormatInternal {
66 * Number of streams relevant for interleaving.
69 int nb_interleaved_streams;
72 * This buffer is only needed when packets were already buffered but
73 * not decoded, for example to get the codec parameters in MPEG
76 struct PacketList *packet_buffer;
77 struct PacketList *packet_buffer_end;
79 /* av_seek_frame() support */
80 int64_t data_offset; /**< offset of the first packet */
83 * Raw packets from the demuxer, prior to parsing and decoding.
84 * This buffer is used for buffering packets until the codec can
85 * be identified, as parsing cannot be done without knowing the
88 struct PacketList *raw_packet_buffer;
89 struct PacketList *raw_packet_buffer_end;
91 * Packets split by the parser get queued here.
93 struct PacketList *parse_queue;
94 struct PacketList *parse_queue_end;
96 * The generic code uses this as a temporary packet
97 * to parse packets; it may also be used for other means
98 * for short periods that are guaranteed not to overlap
99 * with calls to av_read_frame() (or ff_read_packet())
100 * or with each other.
101 * It may be used by demuxers as a replacement for
102 * stack packets (unless they call one of the aforementioned
103 * functions with their own AVFormatContext).
104 * Every user has to ensure that this packet is blank
110 * Used to hold temporary packets.
114 * Remaining size available for raw_packet_buffer, in bytes.
116 #define RAW_PACKET_BUFFER_SIZE 2500000
117 int raw_packet_buffer_remaining_size;
120 * Offset to remap timestamps to be non-negative.
121 * Expressed in timebase units.
122 * @see AVStream.mux_ts_offset
127 * Timebase for the timestamp offset.
129 AVRational offset_timebase;
131 #if FF_API_COMPUTE_PKT_FIELDS2
132 int missing_ts_warning;
135 int inject_global_side_data;
137 int avoid_negative_ts_use_pts;
140 * Timestamp of the end of the shortest stream.
142 int64_t shortest_end;
145 * Whether or not avformat_init_output has already been called
150 * Whether or not avformat_init_output fully initialized streams
152 int streams_initialized;
155 * ID3v2 tag useful for MP3 demuxing
157 AVDictionary *id3v2_meta;
160 * Prefer the codec framerate for avg_frame_rate computation.
162 int prefer_codec_framerate;
165 * Set if chapter ids are strictly monotonic.
167 int chapter_ids_monotonic;
170 struct AVStreamInternal {
172 * Set to 1 if the codec allows reordering, so pts can be different
178 * bitstream filter to run on stream
179 * - encoding: Set by muxer using ff_stream_add_bitstream_filter
185 * Whether or not check_bitstream should still be run on each packet
187 int bitstream_checked;
190 * The codec context used by avformat_find_stream_info, the parser, etc.
192 AVCodecContext *avctx;
194 * 1 if avctx has been initialized with the values from the codec parameters
198 enum AVCodecID orig_codec_id;
200 /* the context for extracting extradata in find_stream_info()
201 * inited=1/bsf=NULL signals that extracting is not possible (codec not
209 * Whether the internal avctx needs to be updated from codecpar (after a late change to codecpar)
211 int need_context_update;
217 #define MAX_STD_TIMEBASES (30*12+30+3+6)
219 * Stream information used internally by avformat_find_stream_info()
223 int64_t duration_gcd;
225 int64_t rfps_duration_sum;
226 double (*duration_error)[2][MAX_STD_TIMEBASES];
227 int64_t codec_info_duration;
228 int64_t codec_info_duration_fields;
229 int frame_delay_evidence;
232 * 0 -> decoder has not been searched for yet.
233 * >0 -> decoder found
234 * <0 -> decoder with codec_id == -found_decoder has not been found
238 int64_t last_duration;
241 * Those are used for average framerate estimation.
243 int64_t fps_first_dts;
244 int fps_first_dts_idx;
245 int64_t fps_last_dts;
246 int fps_last_dts_idx;
250 AVIndexEntry *index_entries; /**< Only used if the format does not
251 support seeking natively. */
252 int nb_index_entries;
253 unsigned int index_entries_allocated_size;
255 int64_t interleaver_chunk_size;
256 int64_t interleaver_chunk_duration;
259 * stream probing state
260 * -1 -> probing finished
261 * 0 -> no probing requested
262 * rest -> perform probing with request_probe being the minimum score to accept.
266 * Indicates that everything up to the next keyframe
267 * should be discarded.
269 int skip_to_keyframe;
272 * Number of samples to skip at the start of the frame decoded from the next packet.
277 * If not 0, the number of samples that should be skipped from the start of
278 * the stream (the samples are removed from packets with pts==0, which also
279 * assumes negative timestamps do not happen).
280 * Intended for use with formats such as mp3 with ad-hoc gapless audio
283 int64_t start_skip_samples;
286 * If not 0, the first audio sample that should be discarded from the stream.
287 * This is broken by design (needs global sample count), but can't be
288 * avoided for broken by design formats such as mp3 with ad-hoc gapless
291 int64_t first_discard_sample;
294 * The sample after last sample that is intended to be discarded after
295 * first_discard_sample. Works on frame boundaries only. Used to prevent
296 * early EOF if the gapless info is broken (considered concatenated mp3s).
298 int64_t last_discard_sample;
301 * Number of internally decoded frames, used internally in libavformat, do not access
302 * its lifetime differs from info which is why it is not in that structure.
304 int nb_decoded_frames;
307 * Timestamp offset added to timestamps before muxing
309 int64_t mux_ts_offset;
312 * Internal data to check for wrapping of the time stamp
314 int64_t pts_wrap_reference;
317 * Options for behavior, when a wrap is detected.
319 * Defined by AV_PTS_WRAP_ values.
321 * If correction is enabled, there are two possibilities:
322 * If the first time stamp is near the wrap point, the wrap offset
323 * will be subtracted, which will create negative time stamps.
324 * Otherwise the offset will be added.
326 int pts_wrap_behavior;
329 * Internal data to prevent doing update_initial_durations() twice
331 int update_initial_durations_done;
333 #define MAX_REORDER_DELAY 16
336 * Internal data to generate dts from pts
338 int64_t pts_reorder_error[MAX_REORDER_DELAY+1];
339 uint8_t pts_reorder_error_count[MAX_REORDER_DELAY+1];
341 int64_t pts_buffer[MAX_REORDER_DELAY+1];
344 * Internal data to analyze DTS and detect faulty mpeg streams
346 int64_t last_dts_for_order_check;
348 uint8_t dts_misordered;
351 * Internal data to inject global side data
353 int inject_global_side_data;
356 * display aspect ratio (0 if unknown)
358 * - decoding: Set by libavformat to calculate sample_aspect_ratio internally
360 AVRational display_aspect_ratio;
362 AVProbeData probe_data;
365 * last packet in packet_buffer for this stream when muxing.
367 struct PacketList *last_in_packet_buffer;
371 #define dynarray_add(tab, nb_ptr, elem)\
373 __typeof__(tab) _tab = (tab);\
374 __typeof__(elem) _elem = (elem);\
375 (void)sizeof(**_tab == _elem); /* check that types are compatible */\
376 av_dynarray_add(_tab, nb_ptr, _elem);\
379 #define dynarray_add(tab, nb_ptr, elem)\
381 av_dynarray_add((tab), nb_ptr, (elem));\
386 * Automatically create sub-directories
388 * @param path will create sub-directories by path
389 * @return 0, or < 0 on error
391 int ff_mkdir_p(const char *path);
393 char *ff_data_to_hex(char *buf, const uint8_t *src, int size, int lowercase);
396 * Parse a string of hexadecimal strings. Any space between the hexadecimal
399 * @param data if non-null, the parsed data is written to this pointer
400 * @param p the string to parse
401 * @return the number of bytes written (or to be written, if data is null)
403 int ff_hex_to_data(uint8_t *data, const char *p);
406 * Add packet to an AVFormatContext's packet_buffer list, determining its
407 * interleaved position using compare() function argument.
408 * @return 0 on success, < 0 on error. pkt will always be blank on return.
410 int ff_interleave_add_packet(AVFormatContext *s, AVPacket *pkt,
411 int (*compare)(AVFormatContext *, const AVPacket *, const AVPacket *));
413 void ff_read_frame_flush(AVFormatContext *s);
415 #define NTP_OFFSET 2208988800ULL
416 #define NTP_OFFSET_US (NTP_OFFSET * 1000000ULL)
418 /** Get the current time since NTP epoch in microseconds. */
419 uint64_t ff_ntp_time(void);
422 * Get the NTP time stamp formatted as per the RFC-5905.
424 * @param ntp_time NTP time in micro seconds (since NTP epoch)
425 * @return the formatted NTP time stamp
427 uint64_t ff_get_formatted_ntp_time(uint64_t ntp_time_us);
430 * Parse the NTP time in micro seconds (since NTP epoch).
432 * @param ntp_ts NTP time stamp formatted as per the RFC-5905.
433 * @return the time in micro seconds (since NTP epoch)
435 uint64_t ff_parse_ntp_time(uint64_t ntp_ts);
438 * Append the media-specific SDP fragment for the media stream c
439 * to the buffer buff.
441 * Note, the buffer needs to be initialized, since it is appended to
444 * @param buff the buffer to append the SDP fragment to
445 * @param size the size of the buff buffer
446 * @param st the AVStream of the media to describe
447 * @param idx the global stream index
448 * @param dest_addr the destination address of the media stream, may be NULL
449 * @param dest_type the destination address type, may be NULL
450 * @param port the destination port of the media stream, 0 if unknown
451 * @param ttl the time to live of the stream, 0 if not multicast
452 * @param fmt the AVFormatContext, which might contain options modifying
455 void ff_sdp_write_media(char *buff, int size, AVStream *st, int idx,
456 const char *dest_addr, const char *dest_type,
457 int port, int ttl, AVFormatContext *fmt);
460 * Write a packet to another muxer than the one the user originally
461 * intended. Useful when chaining muxers, where one muxer internally
462 * writes a received packet to another muxer.
464 * @param dst the muxer to write the packet to
465 * @param dst_stream the stream index within dst to write the packet to
466 * @param pkt the packet to be written
467 * @param src the muxer the packet originally was intended for
468 * @param interleave 0->use av_write_frame, 1->av_interleaved_write_frame
469 * @return the value av_write_frame returned
471 int ff_write_chained(AVFormatContext *dst, int dst_stream, AVPacket *pkt,
472 AVFormatContext *src, int interleave);
475 * Read a whole line of text from AVIOContext. Stop reading after reaching
476 * either a \\n, a \\0 or EOF. The returned string is always \\0-terminated,
477 * and may be truncated if the buffer is too small.
479 * @param s the read-only AVIOContext
480 * @param buf buffer to store the read line
481 * @param maxlen size of the buffer
482 * @return the length of the string written in the buffer, not including the
485 int ff_get_line(AVIOContext *s, char *buf, int maxlen);
488 * Same as ff_get_line but strip the white-space characters in the text tail
490 * @param s the read-only AVIOContext
491 * @param buf buffer to store the read line
492 * @param maxlen size of the buffer
493 * @return the length of the string written in the buffer
495 int ff_get_chomp_line(AVIOContext *s, char *buf, int maxlen);
498 * Read a whole line of text from AVIOContext to an AVBPrint buffer. Stop
499 * reading after reaching a \\r, a \\n, a \\r\\n, a \\0 or EOF. The line
500 * ending characters are NOT included in the buffer, but they are skipped on
503 * @param s the read-only AVIOContext
504 * @param bp the AVBPrint buffer
505 * @return the length of the read line, not including the line endings,
508 int64_t ff_read_line_to_bprint(AVIOContext *s, AVBPrint *bp);
511 * Read a whole line of text from AVIOContext to an AVBPrint buffer overwriting
512 * its contents. Stop reading after reaching a \\r, a \\n, a \\r\\n, a \\0 or
513 * EOF. The line ending characters are NOT included in the buffer, but they
514 * are skipped on the input.
516 * @param s the read-only AVIOContext
517 * @param bp the AVBPrint buffer
518 * @return the length of the read line not including the line endings,
519 * negative on error, or if the buffer becomes truncated.
521 int64_t ff_read_line_to_bprint_overwrite(AVIOContext *s, AVBPrint *bp);
523 #define SPACE_CHARS " \t\r\n"
526 * Callback function type for ff_parse_key_value.
528 * @param key a pointer to the key
529 * @param key_len the number of bytes that belong to the key, including the '='
531 * @param dest return the destination pointer for the value in *dest, may
532 * be null to ignore the value
533 * @param dest_len the length of the *dest buffer
535 typedef void (*ff_parse_key_val_cb)(void *context, const char *key,
536 int key_len, char **dest, int *dest_len);
538 * Parse a string with comma-separated key=value pairs. The value strings
539 * may be quoted and may contain escaped characters within quoted strings.
541 * @param str the string to parse
542 * @param callback_get_buf function that returns where to store the
543 * unescaped value string.
544 * @param context the opaque context pointer to pass to callback_get_buf
546 void ff_parse_key_value(const char *str, ff_parse_key_val_cb callback_get_buf,
550 * Find stream index based on format-specific stream ID
551 * @return stream index, or < 0 on error
553 int ff_find_stream_index(AVFormatContext *s, int id);
556 * Internal version of av_index_search_timestamp
558 int ff_index_search_timestamp(const AVIndexEntry *entries, int nb_entries,
559 int64_t wanted_timestamp, int flags);
562 * Internal version of av_add_index_entry
564 int ff_add_index_entry(AVIndexEntry **index_entries,
565 int *nb_index_entries,
566 unsigned int *index_entries_allocated_size,
567 int64_t pos, int64_t timestamp, int size, int distance, int flags);
569 void ff_configure_buffers_for_index(AVFormatContext *s, int64_t time_tolerance);
574 * @param s media file handle
575 * @param id unique ID for this chapter
576 * @param start chapter start time in time_base units
577 * @param end chapter end time in time_base units
578 * @param title chapter title
580 * @return AVChapter or NULL on error
582 #if FF_API_CHAPTER_ID_INT
583 AVChapter *avpriv_new_chapter(AVFormatContext *s, int id, AVRational time_base,
585 AVChapter *avpriv_new_chapter(AVFormatContext *s, int64_t id, AVRational time_base,
587 int64_t start, int64_t end, const char *title);
590 * Ensure the index uses less memory than the maximum specified in
591 * AVFormatContext.max_index_size by discarding entries if it grows
594 void ff_reduce_index(AVFormatContext *s, int stream_index);
596 enum AVCodecID ff_guess_image2_codec(const char *filename);
599 * Perform a binary search using av_index_search_timestamp() and
600 * AVInputFormat.read_timestamp().
602 * @param target_ts target timestamp in the time base of the given stream
603 * @param stream_index stream number
605 int ff_seek_frame_binary(AVFormatContext *s, int stream_index,
606 int64_t target_ts, int flags);
609 * Update cur_dts of all streams based on the given timestamp and AVStream.
611 * Stream ref_st unchanged, others set cur_dts in their native time base.
612 * Only needed for timestamp wrapping or if (dts not set and pts!=dts).
613 * @param timestamp new dts expressed in time_base of param ref_st
614 * @param ref_st reference stream giving time_base of param timestamp
616 void ff_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp);
618 int ff_find_last_ts(AVFormatContext *s, int stream_index, int64_t *ts, int64_t *pos,
619 int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
622 * Perform a binary search using read_timestamp().
624 * @param target_ts target timestamp in the time base of the given stream
625 * @param stream_index stream number
627 int64_t ff_gen_search(AVFormatContext *s, int stream_index,
628 int64_t target_ts, int64_t pos_min,
629 int64_t pos_max, int64_t pos_limit,
630 int64_t ts_min, int64_t ts_max,
631 int flags, int64_t *ts_ret,
632 int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
635 * Set the time base and wrapping info for a given stream. This will be used
636 * to interpret the stream's timestamps. If the new time base is invalid
637 * (numerator or denominator are non-positive), it leaves the stream
641 * @param pts_wrap_bits number of bits effectively used by the pts
642 * (used for wrap control)
643 * @param pts_num time base numerator
644 * @param pts_den time base denominator
646 void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits,
647 unsigned int pts_num, unsigned int pts_den);
650 * Add side data to a packet for changing parameters to the given values.
651 * Parameters set to 0 aren't included in the change.
653 int ff_add_param_change(AVPacket *pkt, int32_t channels,
654 uint64_t channel_layout, int32_t sample_rate,
655 int32_t width, int32_t height);
658 * Set the timebase for each stream from the corresponding codec timebase and
661 int ff_framehash_write_header(AVFormatContext *s);
664 * Read a transport packet from a media file.
666 * @param s media file handle
667 * @param pkt is filled
668 * @return 0 if OK, AVERROR_xxx on error
670 int ff_read_packet(AVFormatContext *s, AVPacket *pkt);
673 * Add an attached pic to an AVStream.
675 * @param st if set, the stream to add the attached pic to;
676 * if unset, a new stream will be added to s.
677 * @param pb AVIOContext to read data from if buf is unset.
678 * @param buf if set, it contains the data and size information to be used
679 * for the attached pic; if unset, data is read from pb.
680 * @param size the size of the data to read if buf is unset.
682 * @return 0 on success, < 0 on error. On error, this function removes
683 * the stream it has added (if any).
685 int ff_add_attached_pic(AVFormatContext *s, AVStream *st, AVIOContext *pb,
686 AVBufferRef **buf, int size);
689 * Interleave an AVPacket per dts so it can be muxed.
691 * @param s an AVFormatContext for output. pkt resp. out will be added to
692 * resp. taken from its packet buffer.
693 * @param out the interleaved packet will be output here
694 * @param pkt the input packet; will be blank on return if not NULL
695 * @param flush 1 if no further packets are available as input and all
696 * remaining packets should be output
697 * @return 1 if a packet was output, 0 if no packet could be output
698 * (in which case out may be uninitialized), < 0 if an error occurred
700 int ff_interleave_packet_per_dts(AVFormatContext *s, AVPacket *out,
701 AVPacket *pkt, int flush);
703 void ff_free_stream(AVFormatContext *s, AVStream *st);
706 * Return the frame duration in seconds. Return 0 if not available.
708 void ff_compute_frame_duration(AVFormatContext *s, int *pnum, int *pden, AVStream *st,
709 AVCodecParserContext *pc, AVPacket *pkt);
711 unsigned int ff_codec_get_tag(const AVCodecTag *tags, enum AVCodecID id);
713 enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag);
715 int ff_is_intra_only(enum AVCodecID id);
718 * Select a PCM codec based on the given parameters.
720 * @param bps bits-per-sample
721 * @param flt floating-point
722 * @param be big-endian
723 * @param sflags signed flags. each bit corresponds to one byte of bit depth.
724 * e.g. the 1st bit indicates if 8-bit should be signed or
725 * unsigned, the 2nd bit indicates if 16-bit should be signed or
726 * unsigned, etc... This is useful for formats such as WAVE where
727 * only 8-bit is unsigned and all other bit depths are signed.
728 * @return a PCM codec id or AV_CODEC_ID_NONE
730 enum AVCodecID ff_get_pcm_codec_id(int bps, int flt, int be, int sflags);
733 * Chooses a timebase for muxing the specified stream.
735 * The chosen timebase allows sample accurate timestamps based
736 * on the framerate or sample rate for audio streams. It also is
737 * at least as precise as 1/min_precision would be.
739 AVRational ff_choose_timebase(AVFormatContext *s, AVStream *st, int min_precision);
742 * Chooses a timebase for muxing the specified stream.
744 enum AVChromaLocation ff_choose_chroma_location(AVFormatContext *s, AVStream *st);
747 * Generate standard extradata for AVC-Intra based on width/height and field
750 int ff_generate_avci_extradata(AVStream *st);
753 * Add a bitstream filter to a stream.
755 * @param st output stream to add a filter to
756 * @param name the name of the filter to add
757 * @param args filter-specific argument string
758 * @return >0 on success;
759 * AVERROR code on failure
761 int ff_stream_add_bitstream_filter(AVStream *st, const char *name, const char *args);
764 * Copy encoding parameters from source to destination stream
766 * @param dst pointer to destination AVStream
767 * @param src pointer to source AVStream
768 * @return >=0 on success, AVERROR code on error
770 int ff_stream_encode_params_copy(AVStream *dst, const AVStream *src);
773 * Wrap avpriv_io_move and log if error happens.
775 * @param url_src source path
776 * @param url_dst destination path
777 * @return 0 or AVERROR on failure
779 int ff_rename(const char *url_src, const char *url_dst, void *logctx);
782 * Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end
783 * which is always set to 0.
785 * Previously allocated extradata in par will be freed.
787 * @param size size of extradata
788 * @return 0 if OK, AVERROR_xxx on error
790 int ff_alloc_extradata(AVCodecParameters *par, int size);
793 * Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end
794 * which is always set to 0 and fill it from pb.
796 * @param size size of extradata
797 * @return >= 0 if OK, AVERROR_xxx on error
799 int ff_get_extradata(AVFormatContext *s, AVCodecParameters *par, AVIOContext *pb, int size);
802 * add frame for rfps calculation.
804 * @param dts timestamp of the i-th frame
805 * @return 0 if OK, AVERROR_xxx on error
807 int ff_rfps_add_frame(AVFormatContext *ic, AVStream *st, int64_t dts);
809 void ff_rfps_calculate(AVFormatContext *ic);
812 * Flags for AVFormatContext.write_uncoded_frame()
814 enum AVWriteUncodedFrameFlags {
817 * Query whether the feature is possible on this stream.
818 * The frame argument is ignored.
820 AV_WRITE_UNCODED_FRAME_QUERY = 0x0001,
825 * Copies the whilelists from one context to the other
827 int ff_copy_whiteblacklists(AVFormatContext *dst, const AVFormatContext *src);
830 * Returned by demuxers to indicate that data was consumed but discarded
831 * (ignored streams or junk data). The framework will re-call the demuxer.
833 #define FFERROR_REDO FFERRTAG('R','E','D','O')
836 * Utility function to open IO stream of output format.
838 * @param s AVFormatContext
839 * @param url URL or file name to open for writing
840 * @options optional options which will be passed to io_open callback
841 * @return >=0 on success, negative AVERROR in case of failure
843 int ff_format_output_open(AVFormatContext *s, const char *url, AVDictionary **options);
846 * A wrapper around AVFormatContext.io_close that should be used
847 * instead of calling the pointer directly.
849 void ff_format_io_close(AVFormatContext *s, AVIOContext **pb);
852 * Utility function to check if the file uses http or https protocol
854 * @param s AVFormatContext
855 * @param filename URL or file name to open for writing
857 int ff_is_http_proto(char *filename);
860 * Parse creation_time in AVFormatContext metadata if exists and warn if the
863 * @param s AVFormatContext
864 * @param timestamp parsed timestamp in microseconds, only set on successful parsing
865 * @param return_seconds set this to get the number of seconds in timestamp instead of microseconds
866 * @return 1 if OK, 0 if the metadata was not present, AVERROR(EINVAL) on parse error
868 int ff_parse_creation_time_metadata(AVFormatContext *s, int64_t *timestamp, int return_seconds);
871 * Standardize creation_time metadata in AVFormatContext to an ISO-8601
874 * @param s AVFormatContext
875 * @return <0 on error
877 int ff_standardize_creation_time(AVFormatContext *s);
879 #define CONTAINS_PAL 2
881 * Reshuffles the lines to use the user specified stride.
883 * @param ppkt input and output packet
884 * @return negative error code or
885 * 0 if no new packet was allocated
886 * non-zero if a new packet was allocated and ppkt has to be freed
887 * CONTAINS_PAL if in addition to a new packet the old contained a palette
889 int ff_reshuffle_raw_rgb(AVFormatContext *s, AVPacket **ppkt, AVCodecParameters *par, int expected_stride);
892 * Retrieves the palette from a packet, either from side data, or
893 * appended to the video data in the packet itself (raw video only).
894 * It is commonly used after a call to ff_reshuffle_raw_rgb().
896 * Use 0 for the ret parameter to check for side data only.
898 * @param pkt pointer to packet before calling ff_reshuffle_raw_rgb()
899 * @param ret return value from ff_reshuffle_raw_rgb(), or 0
900 * @param palette pointer to palette buffer
901 * @return negative error code or
902 * 1 if the packet has a palette, else 0
904 int ff_get_packet_palette(AVFormatContext *s, AVPacket *pkt, int ret, uint32_t *palette);
907 * Finalize buf into extradata and set its size appropriately.
909 int ff_bprint_to_codecpar_extradata(AVCodecParameters *par, struct AVBPrint *buf);
912 * Find the next packet in the interleaving queue for the given stream.
914 * @return a pointer to a packet if one was found, NULL otherwise.
916 const AVPacket *ff_interleaved_peek(AVFormatContext *s, int stream);
918 int ff_get_muxer_ts_offset(AVFormatContext *s, int stream_index, int64_t *offset);
920 int ff_lock_avformat(void);
921 int ff_unlock_avformat(void);
924 * Set AVFormatContext url field to the provided pointer. The pointer must
925 * point to a valid string. The existing url field is freed if necessary. Also
926 * set the legacy filename field to the same string which was provided in url.
928 void ff_format_set_url(AVFormatContext *s, char *url);
930 void avpriv_register_devices(const AVOutputFormat * const o[], const AVInputFormat * const i[]);
932 #endif /* AVFORMAT_INTERNAL_H */