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 "libavcodec/packet_internal.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 typedef struct FFFormatContext
{
71 * Whether the timestamp shift offset has already been determined.
72 * -1: disabled, 0: not yet determined, 1: determined.
75 AVOID_NEGATIVE_TS_DISABLED
= -1,
76 AVOID_NEGATIVE_TS_UNKNOWN
= 0,
77 AVOID_NEGATIVE_TS_KNOWN
= 1,
78 } avoid_negative_ts_status
;
79 #define AVOID_NEGATIVE_TS_ENABLED(status) ((status) >= 0)
82 * This buffer is only needed when packets were already buffered but
83 * not decoded, for example to get the codec parameters in MPEG
86 PacketList packet_buffer
;
88 /* av_seek_frame() support */
89 int64_t data_offset
; /**< offset of the first packet */
92 * The generic code uses this as a temporary packet
93 * to parse packets or for muxing, especially flushing.
94 * For demuxers, it may also be used for other means
95 * for short periods that are guaranteed not to overlap
96 * with calls to av_read_frame() (or ff_read_packet())
98 * It may be used by demuxers as a replacement for
99 * stack packets (unless they call one of the aforementioned
100 * functions with their own AVFormatContext).
101 * Every user has to ensure that this packet is blank
107 * Used to hold temporary packets for the generic demuxing code.
108 * When muxing, it may be used by muxers to hold packets (even
113 int avoid_negative_ts_use_pts
;
116 * ID3v2 tag useful for MP3 demuxing
118 AVDictionary
*id3v2_meta
;
123 static av_always_inline FFFormatContext
*ffformatcontext(AVFormatContext
*s
)
125 return (FFFormatContext
*)s
;
128 typedef struct FFStream
{
130 * The public context.
134 AVFormatContext
*fmtctx
;
136 * Set to 1 if the codec allows reordering, so pts can be different
142 * bitstream filter to run on stream
143 * - encoding: Set by muxer using ff_stream_add_bitstream_filter
146 struct AVBSFContext
*bsfc
;
149 * Whether or not check_bitstream should still be run on each packet
151 int bitstream_checked
;
154 * The codec context used by avformat_find_stream_info, the parser, etc.
156 struct AVCodecContext
*avctx
;
158 * 1 if avctx has been initialized with the values from the codec parameters
162 /* the context for extracting extradata in find_stream_info()
163 * inited=1/bsf=NULL signals that extracting is not possible (codec not
166 struct AVBSFContext
*bsf
;
171 * Whether the internal avctx needs to be updated from codecpar (after a late change to codecpar)
173 int need_context_update
;
180 * Stream information used internally by avformat_find_stream_info()
182 struct FFStreamInfo
*info
;
184 AVIndexEntry
*index_entries
; /**< Only used if the format does not
185 support seeking natively. */
186 int nb_index_entries
;
187 unsigned int index_entries_allocated_size
;
189 int64_t interleaver_chunk_size
;
190 int64_t interleaver_chunk_duration
;
193 * stream probing state
194 * -1 -> probing finished
195 * 0 -> no probing requested
196 * rest -> perform probing with request_probe being the minimum score to accept.
200 * Indicates that everything up to the next keyframe
201 * should be discarded.
203 int skip_to_keyframe
;
206 * Number of samples to skip at the start of the frame decoded from the next packet.
211 * If not 0, the number of samples that should be skipped from the start of
212 * the stream (the samples are removed from packets with pts==0, which also
213 * assumes negative timestamps do not happen).
214 * Intended for use with formats such as mp3 with ad-hoc gapless audio
217 int64_t start_skip_samples
;
220 * If not 0, the first audio sample that should be discarded from the stream.
221 * This is broken by design (needs global sample count), but can't be
222 * avoided for broken by design formats such as mp3 with ad-hoc gapless
225 int64_t first_discard_sample
;
228 * The sample after last sample that is intended to be discarded after
229 * first_discard_sample. Works on frame boundaries only. Used to prevent
230 * early EOF if the gapless info is broken (considered concatenated mp3s).
232 int64_t last_discard_sample
;
235 * Number of internally decoded frames, used internally in libavformat, do not access
236 * its lifetime differs from info which is why it is not in that structure.
238 int nb_decoded_frames
;
241 * Timestamp offset added to timestamps before muxing
243 int64_t mux_ts_offset
;
246 * This is the lowest ts allowed in this track; it may be set by the muxer
247 * during init or write_header and influences the automatic timestamp
250 int64_t lowest_ts_allowed
;
253 * Internal data to check for wrapping of the time stamp
255 int64_t pts_wrap_reference
;
258 * Options for behavior, when a wrap is detected.
260 * Defined by AV_PTS_WRAP_ values.
262 * If correction is enabled, there are two possibilities:
263 * If the first time stamp is near the wrap point, the wrap offset
264 * will be subtracted, which will create negative time stamps.
265 * Otherwise the offset will be added.
267 int pts_wrap_behavior
;
270 * Internal data to prevent doing update_initial_durations() twice
272 int update_initial_durations_done
;
274 #define MAX_REORDER_DELAY 16
277 * Internal data to generate dts from pts
279 int64_t pts_reorder_error
[MAX_REORDER_DELAY
+1];
280 uint8_t pts_reorder_error_count
[MAX_REORDER_DELAY
+1];
282 int64_t pts_buffer
[MAX_REORDER_DELAY
+1];
285 * Internal data to analyze DTS and detect faulty mpeg streams
287 int64_t last_dts_for_order_check
;
289 uint8_t dts_misordered
;
292 * display aspect ratio (0 if unknown)
294 * - decoding: Set by libavformat to calculate sample_aspect_ratio internally
296 AVRational display_aspect_ratio
;
298 AVProbeData probe_data
;
301 * last packet in packet_buffer for this stream when muxing.
303 PacketListEntry
*last_in_packet_buffer
;
306 int last_IP_duration
;
309 * Number of packets to buffer for codec probing
313 /* av_read_frame() support */
314 enum AVStreamParseType need_parsing
;
315 struct AVCodecParserContext
*parser
;
318 * Number of frames that have been demuxed during avformat_find_stream_info()
320 int codec_info_nb_frames
;
324 * This is the MPEG-TS stream identifier +1
327 int stream_identifier
;
329 // Timestamp generation support:
331 * Timestamp corresponding to the last dts sync point.
333 * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
334 * a DTS is received from the underlying container. Otherwise set to
335 * AV_NOPTS_VALUE by default.
340 const struct AVCodecDescriptor
*codec_desc
;
342 #if FF_API_INTERNAL_TIMING
343 AVRational transferred_mux_tb
;
347 static av_always_inline FFStream
*ffstream(AVStream
*st
)
349 return (FFStream
*)st
;
352 static av_always_inline
const FFStream
*cffstream(const AVStream
*st
)
354 return (const FFStream
*)st
;
357 #if defined (__GNUC__) || defined (__clang__)
358 #define dynarray_add(tab, nb_ptr, elem)\
360 __typeof__(tab) _tab = (tab);\
361 __typeof__(elem) _elem = (elem);\
362 (void)sizeof(**_tab == _elem); /* check that types are compatible */\
363 av_dynarray_add(_tab, nb_ptr, _elem);\
366 #define dynarray_add(tab, nb_ptr, elem)\
368 av_dynarray_add((tab), nb_ptr, (elem));\
373 * Automatically create sub-directories
375 * @param path will create sub-directories by path
376 * @return 0, or < 0 on error
378 int ff_mkdir_p(const char *path
);
381 * Write hexadecimal string corresponding to given binary data. The string
382 * is zero-terminated.
384 * @param buf the output string is written here;
385 * needs to be at least 2 * size + 1 bytes long.
386 * @param src the input data to be transformed.
387 * @param size the size (in byte) of src.
388 * @param lowercase determines whether to use the range [0-9a-f] or [0-9A-F].
391 char *ff_data_to_hex(char *buf
, const uint8_t *src
, int size
, int lowercase
);
394 * Parse a string of hexadecimal strings. Any space between the hexadecimal
397 * @param data if non-null, the parsed data is written to this pointer
398 * @param p the string to parse
399 * @return the number of bytes written (or to be written, if data is null)
401 int ff_hex_to_data(uint8_t *data
, const char *p
);
403 #define NTP_OFFSET 2208988800ULL
404 #define NTP_OFFSET_US (NTP_OFFSET * 1000000ULL)
406 /** Get the current time since NTP epoch in microseconds. */
407 uint64_t ff_ntp_time(void);
410 * Get the NTP time stamp formatted as per the RFC-5905.
412 * @param ntp_time NTP time in micro seconds (since NTP epoch)
413 * @return the formatted NTP time stamp
415 uint64_t ff_get_formatted_ntp_time(uint64_t ntp_time_us
);
418 * Parse the NTP time in micro seconds (since NTP epoch).
420 * @param ntp_ts NTP time stamp formatted as per the RFC-5905.
421 * @return the time in micro seconds (since NTP epoch)
423 uint64_t ff_parse_ntp_time(uint64_t ntp_ts
);
426 * Append the media-specific SDP fragment for the media stream c
427 * to the buffer buff.
429 * Note, the buffer needs to be initialized, since it is appended to
432 * @param buff the buffer to append the SDP fragment to
433 * @param size the size of the buff buffer
434 * @param st the AVStream of the media to describe
435 * @param idx the global stream index
436 * @param dest_addr the destination address of the media stream, may be NULL
437 * @param dest_type the destination address type, may be NULL
438 * @param port the destination port of the media stream, 0 if unknown
439 * @param ttl the time to live of the stream, 0 if not multicast
440 * @param fmt the AVFormatContext, which might contain options modifying
442 * @return 0 on success, a negative error code on failure
444 int ff_sdp_write_media(char *buff
, int size
, const AVStream
*st
, int idx
,
445 const char *dest_addr
, const char *dest_type
,
446 int port
, int ttl
, AVFormatContext
*fmt
);
449 * Read a whole line of text from AVIOContext. Stop reading after reaching
450 * either a \\n, a \\0 or EOF. The returned string is always \\0-terminated,
451 * and may be truncated if the buffer is too small.
453 * @param s the read-only AVIOContext
454 * @param buf buffer to store the read line
455 * @param maxlen size of the buffer
456 * @return the length of the string written in the buffer, not including the
459 int ff_get_line(AVIOContext
*s
, char *buf
, int maxlen
);
462 * Same as ff_get_line but strip the white-space characters in the text tail
464 * @param s the read-only AVIOContext
465 * @param buf buffer to store the read line
466 * @param maxlen size of the buffer
467 * @return the length of the string written in the buffer
469 int ff_get_chomp_line(AVIOContext
*s
, char *buf
, int maxlen
);
471 #define SPACE_CHARS " \t\r\n"
474 * Callback function type for ff_parse_key_value.
476 * @param key a pointer to the key
477 * @param key_len the number of bytes that belong to the key, including the '='
479 * @param dest return the destination pointer for the value in *dest, may
480 * be null to ignore the value
481 * @param dest_len the length of the *dest buffer
483 typedef void (*ff_parse_key_val_cb
)(void *context
, const char *key
,
484 int key_len
, char **dest
, int *dest_len
);
486 * Parse a string with comma-separated key=value pairs. The value strings
487 * may be quoted and may contain escaped characters within quoted strings.
489 * @param str the string to parse
490 * @param callback_get_buf function that returns where to store the
491 * unescaped value string.
492 * @param context the opaque context pointer to pass to callback_get_buf
494 void ff_parse_key_value(const char *str
, ff_parse_key_val_cb callback_get_buf
,
497 enum AVCodecID
ff_guess_image2_codec(const char *filename
);
500 * Set the time base and wrapping info for a given stream. This will be used
501 * to interpret the stream's timestamps. If the new time base is invalid
502 * (numerator or denominator are non-positive), it leaves the stream
506 * @param pts_wrap_bits number of bits effectively used by the pts
507 * (used for wrap control)
508 * @param pts_num time base numerator
509 * @param pts_den time base denominator
511 void avpriv_set_pts_info(AVStream
*st
, int pts_wrap_bits
,
512 unsigned int pts_num
, unsigned int pts_den
);
515 * Set the timebase for each stream from the corresponding codec timebase and
518 int ff_framehash_write_header(AVFormatContext
*s
);
521 * Remove a stream from its AVFormatContext and free it.
522 * The stream must be the last stream of the AVFormatContext.
524 void ff_remove_stream(AVFormatContext
*s
, AVStream
*st
);
527 * Remove a stream group from its AVFormatContext and free it.
528 * The stream group must be the last stream group of the AVFormatContext.
530 void ff_remove_stream_group(AVFormatContext
*s
, AVStreamGroup
*stg
);
532 unsigned int ff_codec_get_tag(const AVCodecTag
*tags
, enum AVCodecID id
);
534 enum AVCodecID
ff_codec_get_id(const AVCodecTag
*tags
, unsigned int tag
);
537 * Select a PCM codec based on the given parameters.
539 * @param bps bits-per-sample
540 * @param flt floating-point
541 * @param be big-endian
542 * @param sflags signed flags. each bit corresponds to one byte of bit depth.
543 * e.g. the 1st bit indicates if 8-bit should be signed or
544 * unsigned, the 2nd bit indicates if 16-bit should be signed or
545 * unsigned, etc... This is useful for formats such as WAVE where
546 * only 8-bit is unsigned and all other bit depths are signed.
547 * @return a PCM codec id or AV_CODEC_ID_NONE
549 enum AVCodecID
ff_get_pcm_codec_id(int bps
, int flt
, int be
, int sflags
);
552 * Create a new stream and copy to it all parameters from a source stream, with
553 * the exception of the index field, which is set when the new stream is
556 * @param dst_ctx pointer to the context in which the new stream is created
557 * @param src pointer to source AVStream
558 * @return pointer to the new stream or NULL on error
560 AVStream
*ff_stream_clone(AVFormatContext
*dst_ctx
, const AVStream
*src
);
563 * Wrap ffurl_move() and log if error happens.
565 * @param url_src source path
566 * @param url_dst destination path
567 * @return 0 or AVERROR on failure
569 int ff_rename(const char *url_src
, const char *url_dst
, void *logctx
);
572 * Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end
573 * which is always set to 0.
575 * Previously allocated extradata in par will be freed.
577 * @param size size of extradata
578 * @return 0 if OK, AVERROR_xxx on error
580 int ff_alloc_extradata(AVCodecParameters
*par
, int size
);
583 * Copies the whilelists from one context to the other
585 int ff_copy_whiteblacklists(AVFormatContext
*dst
, const AVFormatContext
*src
);
588 * A wrapper around AVFormatContext.io_close that should be used
589 * instead of calling the pointer directly.
591 * @param s AVFormatContext
592 * @param *pb the AVIOContext to be closed and freed. Can be NULL.
593 * @return >=0 on success, negative AVERROR in case of failure
595 int ff_format_io_close(AVFormatContext
*s
, AVIOContext
**pb
);
598 * Utility function to check if the file uses http or https protocol
600 * @param s AVFormatContext
601 * @param filename URL or file name to open for writing
603 int ff_is_http_proto(const char *filename
);
607 * Finalize buf into extradata and set its size appropriately.
609 int ff_bprint_to_codecpar_extradata(AVCodecParameters
*par
, struct AVBPrint
*buf
);
612 * Set AVFormatContext url field to the provided pointer. The pointer must
613 * point to a valid string. The existing url field is freed if necessary. Also
614 * set the legacy filename field to the same string which was provided in url.
616 void ff_format_set_url(AVFormatContext
*s
, char *url
);
619 * Return a positive value if the given url has one of the given
620 * extensions, negative AVERROR on error, 0 otherwise.
622 * @param url url to check against the given extensions
623 * @param extensions a comma-separated list of filename extensions
625 int ff_match_url_ext(const char *url
, const char *extensions
);
628 * Return in 'buf' the path with '%d' replaced by a number.
630 * Also handles the '%0nd' format where 'n' is the total number
631 * of digits and '%%'.
633 * @param buf destination buffer
634 * @param path path with substitution template
635 * @param number the number to substitute
636 * @param flags AV_FRAME_FILENAME_FLAGS_*
637 * @return 0 if OK, <0 on error.
639 int ff_bprint_get_frame_filename(struct AVBPrint
*buf
, const char *path
, int64_t number
, int flags
);
642 * Set a dictionary value to an ISO-8601 compliant timestamp string.
644 * @param dict pointer to a pointer to a dictionary struct. If *dict is NULL
645 * a dictionary struct is allocated and put in *dict.
646 * @param key metadata key
647 * @param timestamp unix timestamp in microseconds
648 * @return <0 on error
650 int ff_dict_set_timestamp(AVDictionary
**dict
, const char *key
, int64_t timestamp
);
653 * Set a list of query string options on an object. Only the objects own
654 * options will be set.
656 * @param obj the object to set options on
657 * @param str the query string
658 * @param allow_unknown ignore unknown query string options. This can be OK if
659 * nested protocols are used.
660 * @return <0 on error
662 int ff_parse_opts_from_query_string(void *obj
, const char *str
, int allow_unkown
);
665 * Make a RFC 4281/6381 like string describing a codec.
667 * @param logctx a context for potential log messages
668 * @param par pointer to an AVCodecParameters struct describing the codec
669 * @param frame_rate an optional pointer to AVRational for the frame rate,
670 * for deciding the right profile for video codecs
671 * @param str the output string buffer
672 * @param size the size of the string pointed to by str
673 * @return <0 on error
675 int ff_make_codec_str(void *logctx
, const AVCodecParameters
*par
,
676 const AVRational
*frame_rate
, struct AVBPrint
*out
);
678 #endif /* AVFORMAT_INTERNAL_H */