4 Muxers are configured elements in FFmpeg which allow writing
5 multimedia streams to a particular type of file.
7 When you configure your FFmpeg build, all the supported muxers
8 are enabled by default. You can list all available muxers using the
9 configure option @code{--list-muxers}.
11 You can disable all the muxers with the configure option
12 @code{--disable-muxers} and selectively enable / disable single muxers
13 with the options @code{--enable-muxer=@var{MUXER}} /
14 @code{--disable-muxer=@var{MUXER}}.
16 The option @code{-muxers} of the ff* tools will display the list of
17 enabled muxers. Use @code{-formats} to view a combined list of
18 enabled demuxers and muxers.
20 A description of some of the currently available muxers follows.
25 Audio Interchange File Format muxer.
29 It accepts the following options:
33 Enable ID3v2 tags writing when set to 1. Default is 0 (disabled).
36 Select ID3v2 version to write. Currently only version 3 and 4 (aka.
37 ID3v2.3 and ID3v2.4) are supported. The default is version 4.
44 Advanced Systems Format muxer.
46 Note that Windows Media Audio (wma) and Windows Media Video (wmv) use this
51 It accepts the following options:
55 Set the muxer packet size. By tuning this setting you may reduce data
56 fragmentation or muxer overhead depending on your source. Default value is
57 3200, minimum is 100, maximum is 64k.
64 Audio Video Interleaved muxer.
68 It accepts the following options:
71 @item reserve_index_space
72 Reserve the specified amount of bytes for the OpenDML master index of each
73 stream within the file header. By default additional master indexes are
74 embedded within the data packets if there is no space left in the first master
75 index and are linked together as a chain of indexes. This index structure can
76 cause problems for some use cases, e.g. third-party software strictly relying
77 on the OpenDML index specification or when file seeking is slow. Reserving
78 enough index space in the file header avoids these problems.
80 The required index space depends on the output file size and should be about 16
81 bytes per gigabyte. When this option is omitted or set to zero the necessary
82 index space is guessed.
84 @item write_channel_mask
85 Write the channel layout mask into the audio stream header.
87 This option is enabled by default. Disabling the channel mask can be useful in
88 specific scenarios, e.g. when merging multiple audio streams into one for
89 compatibility with software that only supports a single audio stream in AVI
90 (see @ref{amerge,,the "amerge" section in the ffmpeg-filters manual,ffmpeg-filters}).
97 Chromaprint fingerprinter.
99 This muxer feeds audio data to the Chromaprint library,
100 which generates a fingerprint for the provided audio data. See @url{https://acoustid.org/chromaprint}
102 It takes a single signed native-endian 16-bit raw audio stream of at most 2 channels.
107 @item silence_threshold
108 Threshold for detecting silence, ranges from -1 to 32767. -1 disables silence detection and
109 is required for use with the AcoustID service. Default is -1.
112 Version of algorithm to fingerprint with. Range is 0 to 4. Version 2 requires that silence
113 detection be enabled. Default is 1.
116 Format to output the fingerprint as. Accepts the following options:
119 Binary raw fingerprint
122 Binary compressed fingerprint
125 Base64 compressed fingerprint @emph{(default)}
134 CRC (Cyclic Redundancy Check) testing format.
136 This muxer computes and prints the Adler-32 CRC of all the input audio
137 and video frames. By default audio frames are converted to signed
138 16-bit raw audio and video frames to raw video before computing the
141 The output of the muxer consists of a single line of the form:
142 CRC=0x@var{CRC}, where @var{CRC} is a hexadecimal number 0-padded to
143 8 digits containing the CRC for all the decoded input frames.
145 See also the @ref{framecrc} muxer.
149 For example to compute the CRC of the input, and store it in the file
152 ffmpeg -i INPUT -f crc out.crc
155 You can print the CRC to stdout with the command:
157 ffmpeg -i INPUT -f crc -
160 You can select the output format of each frame with @command{ffmpeg} by
161 specifying the audio and video codec and format. For example to
162 compute the CRC of the input audio converted to PCM unsigned 8-bit
163 and the input video converted to MPEG-2 video, use the command:
165 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f crc -
170 Adobe Flash Video Format muxer.
172 This muxer accepts the following options:
176 @item flvflags @var{flags}
181 @item aac_seq_header_detect
182 Place AAC sequence header based on audio stream data.
184 @item no_sequence_end
185 Disable sequence end tag.
188 Disable metadata tag.
190 @item no_duration_filesize
191 Disable duration and filesize in metadata when they are equal to zero
192 at the end of stream. (Be used to non-seekable living stream).
194 @item add_keyframe_index
195 Used to facilitate seeking; particularly for HTTP pseudo streaming.
202 Dynamic Adaptive Streaming over HTTP (DASH) muxer that creates segments
203 and manifest files according to the MPEG-DASH standard ISO/IEC 23009-1:2014.
205 For more information see:
209 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
211 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
214 It creates a MPD manifest file and segment files for each stream.
216 The segment filename might contain pre-defined identifiers used with SegmentTemplate
217 as defined in section 5.3.9.4.4 of the standard. Available identifiers are "$RepresentationID$",
218 "$Number$", "$Bandwidth$" and "$Time$".
219 In addition to the standard identifiers, an ffmpeg-specific "$ext$" identifier is also supported.
220 When specified ffmpeg will replace $ext$ in the file name with muxing format's extensions such as mp4, webm etc.,
223 ffmpeg -re -i <input> -map 0 -map 0 -c:a libfdk_aac -c:v libx264
224 -b:v:0 800k -b:v:1 300k -s:v:1 320x170 -profile:v:1 baseline
225 -profile:v:0 main -bf 1 -keyint_min 120 -g 120 -sc_threshold 0
226 -b_strategy 0 -ar:a:1 22050 -use_timeline 1 -use_template 1
227 -window_size 5 -adaptation_sets "id=0,streams=v id=1,streams=a"
228 -f dash /path/to/out.mpd
232 @item -min_seg_duration @var{microseconds}
233 This is a deprecated option to set the segment length in microseconds, use @var{seg_duration} instead.
234 @item -seg_duration @var{duration}
235 Set the segment length in seconds (fractional value can be set). The value is
236 treated as average segment duration when @var{use_template} is enabled and
237 @var{use_timeline} is disabled and as minimum segment duration for all the other
239 @item -window_size @var{size}
240 Set the maximum number of segments kept in the manifest.
241 @item -extra_window_size @var{size}
242 Set the maximum number of segments kept outside of the manifest before removing from disk.
243 @item -remove_at_exit @var{remove}
244 Enable (1) or disable (0) removal of all segments when finished.
245 @item -use_template @var{template}
246 Enable (1) or disable (0) use of SegmentTemplate instead of SegmentList.
247 @item -use_timeline @var{timeline}
248 Enable (1) or disable (0) use of SegmentTimeline in SegmentTemplate.
249 @item -single_file @var{single_file}
250 Enable (1) or disable (0) storing all segments in one file, accessed using byte ranges.
251 @item -single_file_name @var{file_name}
252 DASH-templated name to be used for baseURL. Implies @var{single_file} set to "1". In the template, "$ext$" is replaced with the file name extension specific for the segment format.
253 @item -init_seg_name @var{init_name}
254 DASH-templated name to used for the initialization segment. Default is "init-stream$RepresentationID$.$ext$". "$ext$" is replaced with the file name extension specific for the segment format.
255 @item -media_seg_name @var{segment_name}
256 DASH-templated name to used for the media segments. Default is "chunk-stream$RepresentationID$-$Number%05d$.$ext$". "$ext$" is replaced with the file name extension specific for the segment format.
257 @item -utc_timing_url @var{utc_url}
258 URL of the page that will return the UTC timestamp in ISO format. Example: "https://time.akamai.com/?iso"
259 @item method @var{method}
260 Use the given HTTP method to create output files. Generally set to PUT or POST.
261 @item -http_user_agent @var{user_agent}
262 Override User-Agent field in HTTP header. Applicable only for HTTP output.
263 @item -http_persistent @var{http_persistent}
264 Use persistent HTTP connections. Applicable only for HTTP output.
265 @item -hls_playlist @var{hls_playlist}
266 Generate HLS playlist files as well. The master playlist is generated with the filename master.m3u8.
267 One media playlist file is generated for each stream with filenames media_0.m3u8, media_1.m3u8, etc.
268 @item -streaming @var{streaming}
269 Enable (1) or disable (0) chunk streaming mode of output. In chunk streaming
270 mode, each frame will be a moof fragment which forms a chunk.
271 @item -adaptation_sets @var{adaptation_sets}
272 Assign streams to AdaptationSets. Syntax is "id=x,streams=a,b,c id=y,streams=d,e" with x and y being the IDs
273 of the adaptation sets and a,b,c,d and e are the indices of the mapped streams.
275 To map all video (or audio) streams to an AdaptationSet, "v" (or "a") can be used as stream identifier instead of IDs.
277 When no assignment is defined, this defaults to an AdaptationSet for each stream.
278 @item -timeout @var{timeout}
279 Set timeout for socket I/O operations. Applicable only for HTTP output.
280 @item -index_correction @var{index_correction}
281 Enable (1) or Disable (0) segment index correction logic. Applicable only when
282 @var{use_template} is enabled and @var{use_timeline} is disabled.
284 When enabled, the logic monitors the flow of segment indexes. If a streams's
285 segment index value is not at the expected real time position, then the logic
286 corrects that index value.
288 Typically this logic is needed in live streaming use cases. The network bandwidth
289 fluctuations are common during long run streaming. Each fluctuation can cause
290 the segment indexes fall behind the expected real time position.
291 @item -format_options @var{options_list}
292 Set container format (mp4/webm) options using a @code{:} separated list of
293 key=value parameters. Values containing @code{:} special characters must be
296 @item -dash_segment_type @var{dash_segment_type}
299 If this flag is set, the dash segment files format will be selected based on the stream codec. This is the default mode.
302 If this flag is set, the dash segment files will be in in ISOBMFF format.
305 If this flag is set, the dash segment files will be in in WebM format.
307 @item -ignore_io_errors @var{ignore_io_errors}
308 Ignore IO errors during open and write. Useful for long-duration runs with network output.
310 @item -lhls @var{lhls}
311 Enable Low-latency HLS(LHLS). Adds #EXT-X-PREFETCH tag with current segment's URI.
312 Apple doesn't have an official spec for LHLS. Meanwhile hls.js player folks are
313 trying to standardize a open LHLS spec. The draft spec is available in https://github.com/video-dev/hlsjs-rfcs/blob/lhls-spec/proposals/0001-lhls.md
314 This option will also try to comply with the above open spec, till Apple's spec officially supports it.
315 Applicable only when @var{streaming} and @var{hls_playlist} options are enabled.
316 This is an experimental feature.
318 @item -master_m3u8_publish_rate @var{master_m3u8_publish_rate}
319 Publish master playlist repeatedly every after specified number of segment intervals.
326 Per-packet CRC (Cyclic Redundancy Check) testing format.
328 This muxer computes and prints the Adler-32 CRC for each audio
329 and video packet. By default audio frames are converted to signed
330 16-bit raw audio and video frames to raw video before computing the
333 The output of the muxer consists of a line for each audio and video
336 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
339 @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
344 For example to compute the CRC of the audio and video frames in
345 @file{INPUT}, converted to raw audio and video packets, and store it
346 in the file @file{out.crc}:
348 ffmpeg -i INPUT -f framecrc out.crc
351 To print the information to stdout, use the command:
353 ffmpeg -i INPUT -f framecrc -
356 With @command{ffmpeg}, you can select the output format to which the
357 audio and video frames are encoded before computing the CRC for each
358 packet by specifying the audio and video codec. For example, to
359 compute the CRC of each decoded input audio frame converted to PCM
360 unsigned 8-bit and of each decoded input video frame converted to
361 MPEG-2 video, use the command:
363 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
366 See also the @ref{crc} muxer.
371 Per-packet hash testing format.
373 This muxer computes and prints a cryptographic hash for each audio
374 and video packet. This can be used for packet-by-packet equality
375 checks without having to individually do a binary comparison on each.
377 By default audio frames are converted to signed 16-bit raw audio and
378 video frames to raw video before computing the hash, but the output
379 of explicit conversions to other codecs can also be used. It uses the
380 SHA-256 cryptographic hash function by default, but supports several
383 The output of the muxer consists of a line for each audio and video
386 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
389 @var{hash} is a hexadecimal number representing the computed hash
393 @item hash @var{algorithm}
394 Use the cryptographic hash function specified by the string @var{algorithm}.
395 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
396 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
397 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
398 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
404 To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
405 converted to raw audio and video packets, and store it in the file
408 ffmpeg -i INPUT -f framehash out.sha256
411 To print the information to stdout, using the MD5 hash function, use
414 ffmpeg -i INPUT -f framehash -hash md5 -
417 See also the @ref{hash} muxer.
422 Per-packet MD5 testing format.
424 This is a variant of the @ref{framehash} muxer. Unlike that muxer,
425 it defaults to using the MD5 hash function.
429 To compute the MD5 hash of the audio and video frames in @file{INPUT},
430 converted to raw audio and video packets, and store it in the file
433 ffmpeg -i INPUT -f framemd5 out.md5
436 To print the information to stdout, use the command:
438 ffmpeg -i INPUT -f framemd5 -
441 See also the @ref{framehash} and @ref{md5} muxers.
448 It accepts the following options:
452 Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
453 for looping indefinitely (default).
456 Force the delay (expressed in centiseconds) after the last frame. Each frame
457 ends with a delay until the next frame. The default is @code{-1}, which is a
458 special value to tell the muxer to re-use the previous delay. In case of a
459 loop, you might want to customize this value to mark a pause for instance.
462 For example, to encode a gif looping 10 times, with a 5 seconds delay between
465 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
468 Note 1: if you wish to extract the frames into separate GIF files, you need to
469 force the @ref{image2} muxer:
471 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
474 Note 2: the GIF format has a very large time base: the delay between two frames
475 can therefore not be smaller than one centi second.
482 This muxer computes and prints a cryptographic hash of all the input
483 audio and video frames. This can be used for equality checks without
484 having to do a complete binary comparison.
486 By default audio frames are converted to signed 16-bit raw audio and
487 video frames to raw video before computing the hash, but the output
488 of explicit conversions to other codecs can also be used. Timestamps
489 are ignored. It uses the SHA-256 cryptographic hash function by default,
490 but supports several other algorithms.
492 The output of the muxer consists of a single line of the form:
493 @var{algo}=@var{hash}, where @var{algo} is a short string representing
494 the hash function used, and @var{hash} is a hexadecimal number
495 representing the computed hash.
498 @item hash @var{algorithm}
499 Use the cryptographic hash function specified by the string @var{algorithm}.
500 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
501 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
502 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
503 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
509 To compute the SHA-256 hash of the input converted to raw audio and
510 video, and store it in the file @file{out.sha256}:
512 ffmpeg -i INPUT -f hash out.sha256
515 To print an MD5 hash to stdout use the command:
517 ffmpeg -i INPUT -f hash -hash md5 -
520 See also the @ref{framehash} muxer.
525 Apple HTTP Live Streaming muxer that segments MPEG-TS according to
526 the HTTP Live Streaming (HLS) specification.
528 It creates a playlist file, and one or more segment files. The output filename
529 specifies the playlist filename.
531 By default, the muxer creates a file for each segment produced. These files
532 have the same name as the playlist, followed by a sequential number and a
535 Make sure to require a closed GOP when encoding and to set the GOP
536 size to fit your segment time constraint.
538 For example, to convert an input file with @command{ffmpeg}:
540 ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
542 This example will produce the playlist, @file{out.m3u8}, and segment files:
543 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
545 See also the @ref{segment} muxer, which provides a more generic and
546 flexible implementation of a segmenter, and can be used to perform HLS
551 This muxer supports the following options:
554 @item hls_init_time @var{seconds}
555 Set the initial target segment length in seconds. Default value is @var{0}.
556 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
557 After the initial playlist is filled @command{ffmpeg} will cut segments
558 at duration equal to @code{hls_time}
560 @item hls_time @var{seconds}
561 Set the target segment length in seconds. Default value is 2.
562 Segment will be cut on the next key frame after this time has passed.
564 @item hls_list_size @var{size}
565 Set the maximum number of playlist entries. If set to 0 the list file
566 will contain all the segments. Default value is 5.
568 @item hls_delete_threshold @var{size}
569 Set the number of unreferenced segments to keep on disk before @code{hls_flags delete_segments}
570 deletes them. Increase this to allow continue clients to download segments which
571 were recently referenced in the playlist. Default value is 1, meaning segments older than
572 @code{hls_list_size+1} will be deleted.
574 @item hls_ts_options @var{options_list}
575 Set output format options using a :-separated list of key=value
576 parameters. Values containing @code{:} special characters must be
579 @item hls_wrap @var{wrap}
580 This is a deprecated option, you can use @code{hls_list_size}
581 and @code{hls_flags delete_segments} instead it
583 This option is useful to avoid to fill the disk with many segment
584 files, and limits the maximum number of segment files written to disk
588 @item hls_start_number_source
589 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
590 Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
591 segment and subtitle filenames. In any case, if @code{hls_flags append_list}
592 is set and read playlist sequence number is greater than the specified start sequence number,
593 then that value will be used as start value.
595 It accepts the following values:
599 @item generic (default)
600 Set the starting sequence numbers according to @var{start_number} option value.
603 The start number will be the seconds since epoch (1970-01-01 00:00:00)
606 The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
610 @item start_number @var{number}
611 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
612 when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
613 Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
616 @item hls_allow_cache @var{allowcache}
617 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
619 @item hls_base_url @var{baseurl}
620 Append @var{baseurl} to every entry in the playlist.
621 Useful to generate playlists with absolute paths.
623 Note that the playlist sequence number must be unique for each segment
624 and it is not to be confused with the segment filename sequence number
625 which can be cyclic, for example if the @option{wrap} option is
628 @item hls_segment_filename @var{filename}
629 Set the segment filename. Unless @code{hls_flags single_file} is set,
630 @var{filename} is used as a string format with the segment number:
632 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
634 This example will produce the playlist, @file{out.m3u8}, and segment files:
635 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
637 @var{filename} may contain full path or relative path specification,
638 but only the file name part without any path info will be contained in the m3u8 segment list.
639 Should a relative path be specified, the path of the created segment
640 files will be relative to the current working directory.
641 When strftime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
643 When @code{var_stream_map} is set with two or more variant streams, the
644 @var{filename} pattern must contain the string "%v", this string specifies
645 the position of variant stream index in the generated segment file names.
647 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
648 -map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0 v:1,a:1" \
649 -hls_segment_filename 'file_%v_%03d.ts' out_%v.m3u8
651 This example will produce the playlists segment file sets:
652 @file{file_0_000.ts}, @file{file_0_001.ts}, @file{file_0_002.ts}, etc. and
653 @file{file_1_000.ts}, @file{file_1_001.ts}, @file{file_1_002.ts}, etc.
655 The string "%v" may be present in the filename or in the last directory name
656 containing the file. If the string is present in the directory name, then
657 sub-directories are created after expanding the directory name pattern. This
658 enables creation of segments corresponding to different variant streams in
661 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
662 -map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0 v:1,a:1" \
663 -hls_segment_filename 'vs%v/file_%03d.ts' vs%v/out.m3u8
665 This example will produce the playlists segment file sets:
666 @file{vs0/file_000.ts}, @file{vs0/file_001.ts}, @file{vs0/file_002.ts}, etc. and
667 @file{vs1/file_000.ts}, @file{vs1/file_001.ts}, @file{vs1/file_002.ts}, etc.
670 Same as strftime option, will be deprecated.
673 Use strftime() on @var{filename} to expand the segment filename with localtime.
674 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
675 hls_flag and %%d will be the specifier.
677 ffmpeg -i in.nut -strftime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
679 This example will produce the playlist, @file{out.m3u8}, and segment files:
680 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
681 Note: On some systems/environments, the @code{%s} specifier is not available. See
682 @code{strftime()} documentation.
684 ffmpeg -i in.nut -strftime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
686 This example will produce the playlist, @file{out.m3u8}, and segment files:
687 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
689 @item use_localtime_mkdir
690 Same as strftime_mkdir option, will be deprecated .
693 Used together with -strftime_mkdir, it will create all subdirectories which
694 is expanded in @var{filename}.
696 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y%m%d/file-%Y%m%d-%s.ts' out.m3u8
698 This example will create a directory 201560215 (if it does not exist), and then
699 produce the playlist, @file{out.m3u8}, and segment files:
700 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
703 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y/%m/%d/file-%Y%m%d-%s.ts' out.m3u8
705 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
706 produce the playlist, @file{out.m3u8}, and segment files:
707 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
710 @item hls_key_info_file @var{key_info_file}
711 Use the information in @var{key_info_file} for segment encryption. The first
712 line of @var{key_info_file} specifies the key URI written to the playlist. The
713 key URL is used to access the encryption key during playback. The second line
714 specifies the path to the key file used to obtain the key during the encryption
715 process. The key file is read as a single packed array of 16 octets in binary
716 format. The optional third line specifies the initialization vector (IV) as a
717 hexadecimal string to be used instead of the segment sequence number (default)
718 for encryption. Changes to @var{key_info_file} will result in segment
719 encryption with the new key/IV and an entry in the playlist for the new key
720 URI/IV if @code{hls_flags periodic_rekey} is enabled.
722 Key info file format:
731 http://server/file.key
736 Example key file paths:
744 0123456789ABCDEF0123456789ABCDEF
747 Key info file example:
749 http://server/file.key
751 0123456789ABCDEF0123456789ABCDEF
754 Example shell script:
758 openssl rand 16 > file.key
759 echo $BASE_URL/file.key > file.keyinfo
760 echo file.key >> file.keyinfo
761 echo $(openssl rand -hex 16) >> file.keyinfo
762 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
763 -hls_key_info_file file.keyinfo out.m3u8
766 @item -hls_enc @var{enc}
767 Enable (1) or disable (0) the AES128 encryption.
768 When enabled every segment generated is encrypted and the encryption key
769 is saved as @var{playlist name}.key.
771 @item -hls_enc_key @var{key}
772 Hex-coded 16byte key to encrypt the segments, by default it
773 is randomly generated.
775 @item -hls_enc_key_url @var{keyurl}
776 If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
779 @item -hls_enc_iv @var{iv}
780 Hex-coded 16byte initialization vector for every segment instead
781 of the autogenerated ones.
783 @item hls_segment_type @var{flags}
788 Output segment files in MPEG-2 Transport Stream format. This is
789 compatible with all HLS versions.
792 Output segment files in fragmented MP4 format, similar to MPEG-DASH.
793 fmp4 files may be used in HLS version 7 and above.
797 @item hls_fmp4_init_filename @var{filename}
798 Set filename to the fragment files header file, default filename is @file{init.mp4}.
800 When @code{var_stream_map} is set with two or more variant streams, the
801 @var{filename} pattern must contain the string "%v", this string specifies
802 the position of variant stream index in the generated init file names.
803 The string "%v" may be present in the filename or in the last directory name
804 containing the file. If the string is present in the directory name, then
805 sub-directories are created after expanding the directory name pattern. This
806 enables creation of init files corresponding to different variant streams in
809 @item hls_flags @var{flags}
814 If this flag is set, the muxer will store all segments in a single MPEG-TS
815 file, and will use byte ranges in the playlist. HLS playlists generated with
816 this way will have the version number 4.
819 ffmpeg -i in.nut -hls_flags single_file out.m3u8
821 Will produce the playlist, @file{out.m3u8}, and a single segment file,
824 @item delete_segments
825 Segment files removed from the playlist are deleted after a period of time
826 equal to the duration of the segment plus the duration of the playlist.
829 Append new segments into the end of old segment list,
830 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
832 @item round_durations
833 Round the duration info in the playlist file segment info to integer
834 values, instead of using floating point.
837 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
838 first segment's information.
841 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
844 The file specified by @code{hls_key_info_file} will be checked periodically and
845 detect updates to the encryption info. Be sure to replace this file atomically,
846 including the file containing the AES encryption key.
848 @item independent_segments
849 Add the @code{#EXT-X-INDEPENDENT-SEGMENTS} to playlists that has video segments
850 and when all the segments of that playlist are guaranteed to start with a Key frame.
853 Allow segments to start on frames other than keyframes. This improves
854 behavior on some players when the time between keyframes is inconsistent,
855 but may make things worse on others, and can cause some oddities during
856 seeking. This flag should be used with the @code{hls_time} option.
858 @item program_date_time
859 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
861 @item second_level_segment_index
862 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
863 besides date/time values when strftime is on.
864 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
866 @item second_level_segment_size
867 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
868 expression besides date/time values when strftime is on.
869 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
871 @item second_level_segment_duration
872 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
873 expression besides date/time values when strftime is on.
874 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
877 ffmpeg -i sample.mpeg \
878 -f hls -hls_time 3 -hls_list_size 5 \
879 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
880 -strftime 1 -strftime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
882 This will produce segments like this:
883 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
886 Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
887 serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
888 before they have been added to the m3u8 playlist.
892 @item hls_playlist_type event
893 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
894 @option{hls_list_size} to 0; the playlist can only be appended to.
896 @item hls_playlist_type vod
897 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
898 @option{hls_list_size} to 0; the playlist must not change.
901 Use the given HTTP method to create the hls files.
903 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
905 This example will upload all the mpegts segment files to the HTTP
906 server using the HTTP PUT method, and update the m3u8 files every
907 @code{refresh} times using the same method.
908 Note that the HTTP server must support the given method for uploading
911 @item http_user_agent
912 Override User-Agent field in HTTP header. Applicable only for HTTP output.
915 Map string which specifies how to group the audio, video and subtitle streams
916 into different variant streams. The variant stream groups are separated
918 Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
919 the keys to specify audio, video and subtitle streams respectively.
920 Allowed values are 0 to 9 (limited just based on practical usage).
922 When there are two or more variant streams, the output filename pattern must
923 contain the string "%v", this string specifies the position of variant stream
924 index in the output media playlist filenames. The string "%v" may be present in
925 the filename or in the last directory name containing the file. If the string is
926 present in the directory name, then sub-directories are created after expanding
927 the directory name pattern. This enables creation of variant streams in
931 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
932 -map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0 v:1,a:1" \
933 http://example.com/live/out_%v.m3u8
935 This example creates two hls variant streams. The first variant stream will
936 contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
937 second variant stream will contain video stream of bitrate 256k and audio
938 stream of bitrate 32k. Here, two media playlist with file names out_0.m3u8 and
939 out_1.m3u8 will be created.
941 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
942 -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
943 http://example.com/live/out_%v.m3u8
945 This example creates three hls variant streams. The first variant stream will
946 be a video only stream with video bitrate 1000k, the second variant stream will
947 be an audio only stream with bitrate 64k and the third variant stream will be a
948 video only stream with bitrate 256k. Here, three media playlist with file names
949 out_0.m3u8, out_1.m3u8 and out_2.m3u8 will be created.
951 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
952 -map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0 v:1,a:1" \
953 http://example.com/live/vs_%v/out.m3u8
955 This example creates the variant streams in subdirectories. Here, the first
956 media playlist is created at @file{http://example.com/live/vs_0/out.m3u8} and
957 the second one at @file{http://example.com/live/vs_1/out.m3u8}.
959 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k \
960 -map 0:a -map 0:a -map 0:v -map 0:v -f hls \
961 -var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
962 -master_pl_name master.m3u8 \
963 http://example.com/live/out_%v.m3u8
965 This example creates two audio only and two video only variant streams. In
966 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
967 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
968 and they are mapped to the two video only variant streams with audio group names
969 'aud_low' and 'aud_high'.
971 By default, a single hls variant containing all the encoded streams is created.
974 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
975 -map 0:a -map 0:a -map 0:v -f hls \
976 -var_stream_map "a:0,agroup:aud_low,default:yes a:1,agroup:aud_low v:0,agroup:aud_low" \
977 -master_pl_name master.m3u8 \
978 http://example.com/live/out_%v.m3u8
980 This example creates two audio only and one video only variant streams. In
981 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
982 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
983 and they are mapped to the one video only variant streams with audio group name
984 'aud_low', and the audio group have default stat is NO or YES.
986 By default, a single hls variant containing all the encoded streams is created.
989 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
990 -map 0:a -map 0:a -map 0:v -f hls \
991 -var_stream_map "a:0,agroup:aud_low,default:yes,language=ENG a:1,agroup:aud_low,language:CHN v:0,agroup:aud_low" \
992 -master_pl_name master.m3u8 \
993 http://example.com/live/out_%v.m3u8
995 This example creates two audio only and one video only variant streams. In
996 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
997 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
998 and they are mapped to the one video only variant streams with audio group name
999 'aud_low', and the audio group have default stat is NO or YES, and one audio
1000 have and language is named ENG, the other audio language is named CHN.
1002 By default, a single hls variant containing all the encoded streams is created.
1005 Map string which specifies different closed captions groups and their
1006 attributes. The closed captions stream groups are separated by space.
1007 Expected string format is like this
1008 "ccgroup:<group name>,instreamid:<INSTREAM-ID>,language:<language code> ....".
1009 'ccgroup' and 'instreamid' are mandatory attributes. 'language' is an optional
1011 The closed captions groups configured using this option are mapped to different
1012 variant streams by providing the same 'ccgroup' name in the
1013 @code{var_stream_map} string. If @code{var_stream_map} is not set, then the
1014 first available ccgroup in @code{cc_stream_map} is mapped to the output variant
1015 stream. The examples for these two use cases are given below.
1018 ffmpeg -re -i in.ts -b:v 1000k -b:a 64k -a53cc 1 -f hls \
1019 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en" \
1020 -master_pl_name master.m3u8 \
1021 http://example.com/live/out.m3u8
1023 This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=CLOSED-CAPTIONS} in
1024 the master playlist with group name 'cc', language 'en' (english) and
1025 INSTREAM-ID 'CC1'. Also, it adds @code{CLOSED-CAPTIONS} attribute with group
1026 name 'cc' for the output variant stream.
1028 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1029 -a53cc:0 1 -a53cc:1 1\
1030 -map 0:v -map 0:a -map 0:v -map 0:a -f hls \
1031 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en ccgroup:cc,instreamid:CC2,language:sp" \
1032 -var_stream_map "v:0,a:0,ccgroup:cc v:1,a:1,ccgroup:cc" \
1033 -master_pl_name master.m3u8 \
1034 http://example.com/live/out_%v.m3u8
1036 This example adds two @code{#EXT-X-MEDIA} tags with @code{TYPE=CLOSED-CAPTIONS} in
1037 the master playlist for the INSTREAM-IDs 'CC1' and 'CC2'. Also, it adds
1038 @code{CLOSED-CAPTIONS} attribute with group name 'cc' for the two output variant
1041 @item master_pl_name
1042 Create HLS master playlist with the given name.
1045 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
1047 This example creates HLS master playlist with name master.m3u8 and it is
1048 published at http://example.com/live/
1050 @item master_pl_publish_rate
1051 Publish master play list repeatedly every after specified number of segment intervals.
1054 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
1055 -hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
1058 This example creates HLS master playlist with name master.m3u8 and keep
1059 publishing it repeatedly every after 30 segments i.e. every after 60s.
1061 @item http_persistent
1062 Use persistent HTTP connections. Applicable only for HTTP output.
1065 Set timeout for socket I/O operations. Applicable only for HTTP output.
1067 @item -ignore_io_errors
1068 Ignore IO errors during open, write and delete. Useful for long-duration runs with network output.
1077 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
1081 Size cannot exceed 256 pixels in any dimension
1084 Only BMP and PNG images can be stored
1087 If a BMP image is used, it must be one of the following pixel formats:
1089 BMP Bit Depth FFmpeg Pixel Format
1099 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
1102 If a PNG image is used, it must use the rgba pixel format
1110 The image file muxer writes video frames to image files.
1112 The output filenames are specified by a pattern, which can be used to
1113 produce sequentially numbered series of files.
1114 The pattern may contain the string "%d" or "%0@var{N}d", this string
1115 specifies the position of the characters representing a numbering in
1116 the filenames. If the form "%0@var{N}d" is used, the string
1117 representing the number in each filename is 0-padded to @var{N}
1118 digits. The literal character '%' can be specified in the pattern with
1121 If the pattern contains "%d" or "%0@var{N}d", the first filename of
1122 the file list specified will contain the number 1, all the following
1123 numbers will be sequential.
1125 The pattern may contain a suffix which is used to automatically
1126 determine the format of the image files to write.
1128 For example the pattern "img-%03d.bmp" will specify a sequence of
1129 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
1130 @file{img-010.bmp}, etc.
1131 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
1132 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
1135 @subsection Examples
1137 The following example shows how to use @command{ffmpeg} for creating a
1138 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
1139 taking one image every second from the input video:
1141 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
1144 Note that with @command{ffmpeg}, if the format is not specified with the
1145 @code{-f} option and the output filename specifies an image file
1146 format, the image2 muxer is automatically selected, so the previous
1147 command can be written as:
1149 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
1152 Note also that the pattern must not necessarily contain "%d" or
1153 "%0@var{N}d", for example to create a single image file
1154 @file{img.jpeg} from the start of the input video you can employ the command:
1156 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
1159 The @option{strftime} option allows you to expand the filename with
1160 date and time information. Check the documentation of
1161 the @code{strftime()} function for the syntax.
1163 For example to generate image files from the @code{strftime()}
1164 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
1167 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
1170 You can set the file name with current frame's PTS:
1172 ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
1179 If set to 1, expand the filename with pts from pkt->pts.
1183 Start the sequence from the specified number. Default value is 1.
1186 If set to 1, the filename will always be interpreted as just a
1187 filename, not a pattern, and the corresponding file will be continuously
1188 overwritten with new images. Default value is 0.
1191 If set to 1, expand the filename with date and time information from
1192 @code{strftime()}. Default value is 0.
1195 The image muxer supports the .Y.U.V image file format. This format is
1196 special in that that each image frame consists of three files, for
1197 each of the YUV420P components. To read or write this image file format,
1198 specify the name of the '.Y' file. The muxer will automatically open the
1199 '.U' and '.V' files as required.
1203 Matroska container muxer.
1205 This muxer implements the matroska and webm container specs.
1207 @subsection Metadata
1209 The recognized metadata settings in this muxer are:
1213 Set title name provided to a single track.
1216 Specify the language of the track in the Matroska languages form.
1218 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
1219 639-2/B) form (like "fre" for French), or a language code mixed with a
1220 country code for specialities in languages (like "fre-ca" for Canadian
1224 Set stereo 3D video layout of two views in a single video track.
1226 The following values are recognized:
1231 Both views are arranged side by side, Left-eye view is on the left
1233 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
1235 Both views are arranged in top-bottom orientation, Left-eye view is on top
1236 @item checkerboard_rl
1237 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
1238 @item checkerboard_lr
1239 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
1240 @item row_interleaved_rl
1241 Each view is constituted by a row based interleaving, Right-eye view is first row
1242 @item row_interleaved_lr
1243 Each view is constituted by a row based interleaving, Left-eye view is first row
1244 @item col_interleaved_rl
1245 Both views are arranged in a column based interleaving manner, Right-eye view is first column
1246 @item col_interleaved_lr
1247 Both views are arranged in a column based interleaving manner, Left-eye view is first column
1248 @item anaglyph_cyan_red
1249 All frames are in anaglyph format viewable through red-cyan filters
1251 Both views are arranged side by side, Right-eye view is on the left
1252 @item anaglyph_green_magenta
1253 All frames are in anaglyph format viewable through green-magenta filters
1255 Both eyes laced in one Block, Left-eye view is first
1257 Both eyes laced in one Block, Right-eye view is first
1261 For example a 3D WebM clip can be created using the following command line:
1263 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
1268 This muxer supports the following options:
1271 @item reserve_index_space
1272 By default, this muxer writes the index for seeking (called cues in Matroska
1273 terms) at the end of the file, because it cannot know in advance how much space
1274 to leave for the index at the beginning of the file. However for some use cases
1275 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
1276 index at the beginning of the file.
1278 If this option is set to a non-zero value, the muxer will reserve a given amount
1279 of space in the file header and then try to write the cues there when the muxing
1280 finishes. If the available space does not suffice, muxing will fail. A safe size
1281 for most use cases should be about 50kB per hour of video.
1283 Note that cues are only written if the output is seekable and this option will
1284 have no effect if it is not.
1292 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
1293 defaults to using the MD5 hash function.
1295 @subsection Examples
1297 To compute the MD5 hash of the input converted to raw
1298 audio and video, and store it in the file @file{out.md5}:
1300 ffmpeg -i INPUT -f md5 out.md5
1303 You can print the MD5 to stdout with the command:
1305 ffmpeg -i INPUT -f md5 -
1308 See also the @ref{hash} and @ref{framemd5} muxers.
1310 @section mov, mp4, ismv
1312 MOV/MP4/ISMV (Smooth Streaming) muxer.
1314 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
1315 file has all the metadata about all packets stored in one location
1316 (written at the end of the file, it can be moved to the start for
1317 better playback by adding @var{faststart} to the @var{movflags}, or
1318 using the @command{qt-faststart} tool). A fragmented
1319 file consists of a number of fragments, where packets and metadata
1320 about these packets are stored together. Writing a fragmented
1321 file has the advantage that the file is decodable even if the
1322 writing is interrupted (while a normal MOV/MP4 is undecodable if
1323 it is not properly finished), and it requires less memory when writing
1324 very long files (since writing normal MOV/MP4 files stores info about
1325 every single packet in memory until the file is closed). The downside
1326 is that it is less compatible with other applications.
1330 Fragmentation is enabled by setting one of the AVOptions that define
1331 how to cut the file into fragments:
1334 @item -moov_size @var{bytes}
1335 Reserves space for the moov atom at the beginning of the file instead of placing the
1336 moov atom at the end. If the space reserved is insufficient, muxing will fail.
1337 @item -movflags frag_keyframe
1338 Start a new fragment at each video keyframe.
1339 @item -frag_duration @var{duration}
1340 Create fragments that are @var{duration} microseconds long.
1341 @item -frag_size @var{size}
1342 Create fragments that contain up to @var{size} bytes of payload data.
1343 @item -movflags frag_custom
1344 Allow the caller to manually choose when to cut fragments, by
1345 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
1346 the packets written so far. (This is only useful with other
1347 applications integrating libavformat, not from @command{ffmpeg}.)
1348 @item -min_frag_duration @var{duration}
1349 Don't create fragments that are shorter than @var{duration} microseconds long.
1352 If more than one condition is specified, fragments are cut when
1353 one of the specified conditions is fulfilled. The exception to this is
1354 @code{-min_frag_duration}, which has to be fulfilled for any of the other
1355 conditions to apply.
1357 Additionally, the way the output file is written can be adjusted
1358 through a few other options:
1361 @item -movflags empty_moov
1362 Write an initial moov atom directly at the start of the file, without
1363 describing any samples in it. Generally, an mdat/moov pair is written
1364 at the start of the file, as a normal MOV/MP4 file, containing only
1365 a short portion of the file. With this option set, there is no initial
1366 mdat atom, and the moov atom only describes the tracks but has
1369 This option is implicitly set when writing ismv (Smooth Streaming) files.
1370 @item -movflags separate_moof
1371 Write a separate moof (movie fragment) atom for each track. Normally,
1372 packets for all tracks are written in a moof atom (which is slightly
1373 more efficient), but with this option set, the muxer writes one moof/mdat
1374 pair for each track, making it easier to separate tracks.
1376 This option is implicitly set when writing ismv (Smooth Streaming) files.
1377 @item -movflags skip_sidx
1378 Skip writing of sidx atom. When bitrate overhead due to sidx atom is high,
1379 this option could be used for cases where sidx atom is not mandatory.
1380 When global_sidx flag is enabled, this option will be ignored.
1381 @item -movflags faststart
1382 Run a second pass moving the index (moov atom) to the beginning of the file.
1383 This operation can take a while, and will not work in various situations such
1384 as fragmented output, thus it is not enabled by default.
1385 @item -movflags rtphint
1386 Add RTP hinting tracks to the output file.
1387 @item -movflags disable_chpl
1388 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
1389 and a QuickTime chapter track are written to the file. With this option
1390 set, only the QuickTime chapter track will be written. Nero chapters can
1391 cause failures when the file is reprocessed with certain tagging programs, like
1392 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
1393 @item -movflags omit_tfhd_offset
1394 Do not write any absolute base_data_offset in tfhd atoms. This avoids
1395 tying fragments to absolute byte positions in the file/streams.
1396 @item -movflags default_base_moof
1397 Similarly to the omit_tfhd_offset, this flag avoids writing the
1398 absolute base_data_offset field in tfhd atoms, but does so by using
1399 the new default-base-is-moof flag instead. This flag is new from
1400 14496-12:2012. This may make the fragments easier to parse in certain
1401 circumstances (avoiding basing track fragment location calculations
1402 on the implicit end of the previous track fragment).
1404 Specify @code{on} to force writing a timecode track, @code{off} to disable it
1405 and @code{auto} to write a timecode track only for mov and mp4 output (default).
1406 @item -movflags negative_cts_offsets
1407 Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
1408 be negative. This enables the initial sample to have DTS/CTS of zero, and
1409 reduces the need for edit lists for some cases such as video tracks with
1410 B-frames. Additionally, eases conformance with the DASH-IF interoperability
1413 This option is implicitly set when writing ismv (Smooth Streaming) files.
1415 Write producer time reference box (PRFT) with a specified time source for the
1416 NTP field in the PRFT box. Set value as @samp{wallclock} to specify timesource
1417 as wallclock time and @samp{pts} to specify timesource as input packets' PTS
1420 Setting value to @samp{pts} is applicable only for a live encoding use case,
1421 where PTS values are set as as wallclock time at the source. For example, an
1422 encoding use case with decklink capture source where @option{video_pts} and
1423 @option{audio_pts} are set to @samp{abs_wallclock}.
1428 Smooth Streaming content can be pushed in real time to a publishing
1429 point on IIS with this muxer. Example:
1431 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
1434 @subsection Audible AAX
1436 Audible AAX files are encrypted M4B files, and they can be decrypted by specifying a 4 byte activation secret.
1438 ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
1443 The MP3 muxer writes a raw MP3 stream with the following optional features:
1446 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
1447 2.4 are supported, the @code{id3v2_version} private option controls which one is
1448 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
1451 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
1452 The pictures are supplied to the muxer in form of a video stream with a single
1453 packet. There can be any number of those streams, each will correspond to a
1454 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
1455 to APIC @var{description} and @var{picture type} respectively. See
1456 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
1458 Note that the APIC frames must be written at the beginning, so the muxer will
1459 buffer the audio frames until it gets all the pictures. It is therefore advised
1460 to provide the pictures as soon as possible to avoid excessive buffering.
1463 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
1464 default, but will be written only if the output is seekable. The
1465 @code{write_xing} private option can be used to disable it. The frame contains
1466 various information that may be useful to the decoder, like the audio duration
1470 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1471 enabled with the @code{write_id3v1} private option, but as its capabilities are
1472 very limited, its usage is not recommended.
1477 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1479 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1482 To attach a picture to an mp3 file select both the audio and the picture stream
1485 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1486 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1489 Write a "clean" MP3 without any extra features:
1491 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1496 MPEG transport stream muxer.
1498 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1500 The recognized metadata settings in mpegts muxer are @code{service_provider}
1501 and @code{service_name}. If they are not set the default for
1502 @code{service_provider} is @samp{FFmpeg} and the default for
1503 @code{service_name} is @samp{Service01}.
1507 The muxer options are:
1510 @item mpegts_transport_stream_id @var{integer}
1511 Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
1512 Default is @code{0x0001}.
1514 @item mpegts_original_network_id @var{integer}
1515 Set the @samp{original_network_id}. This is unique identifier of a
1516 network in DVB. Its main use is in the unique identification of a service
1517 through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
1520 @item mpegts_service_id @var{integer}
1521 Set the @samp{service_id}, also known as program in DVB. Default is
1524 @item mpegts_service_type @var{integer}
1525 Set the program @samp{service_type}. Default is @code{digital_tv}.
1526 Accepts the following options:
1529 Any hexadecimal value between @code{0x01} and @code{0xff} as defined in
1534 Digital Radio service.
1537 @item advanced_codec_digital_radio
1538 Advanced Codec Digital Radio service.
1539 @item mpeg2_digital_hdtv
1540 MPEG2 Digital HDTV service.
1541 @item advanced_codec_digital_sdtv
1542 Advanced Codec Digital SDTV service.
1543 @item advanced_codec_digital_hdtv
1544 Advanced Codec Digital HDTV service.
1547 @item mpegts_pmt_start_pid @var{integer}
1548 Set the first PID for PMT. Default is @code{0x1000}. Max is @code{0x1f00}.
1550 @item mpegts_start_pid @var{integer}
1551 Set the first PID for data packets. Default is @code{0x0100}. Max is
1554 @item mpegts_m2ts_mode @var{boolean}
1555 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
1558 @item muxrate @var{integer}
1559 Set a constant muxrate. Default is VBR.
1561 @item pes_payload_size @var{integer}
1562 Set minimum PES packet payload in bytes. Default is @code{2930}.
1564 @item mpegts_flags @var{flags}
1565 Set mpegts flags. Accepts the following options:
1567 @item resend_headers
1568 Reemit PAT/PMT before writing the next packet.
1570 Use LATM packetization for AAC.
1571 @item pat_pmt_at_frames
1572 Reemit PAT and PMT at each video frame.
1574 Conform to System B (DVB) instead of System A (ATSC).
1575 @item initial_discontinuity
1576 Mark the initial packet of each stream as discontinuity.
1579 @item resend_headers @var{integer}
1580 Reemit PAT/PMT before writing the next packet. This option is deprecated:
1581 use @option{mpegts_flags} instead.
1583 @item mpegts_copyts @var{boolean}
1584 Preserve original timestamps, if value is set to @code{1}. Default value
1585 is @code{-1}, which results in shifting timestamps so that they start from 0.
1587 @item omit_video_pes_length @var{boolean}
1588 Omit the PES packet length for video packets. Default is @code{1} (true).
1590 @item pcr_period @var{integer}
1591 Override the default PCR retransmission time in milliseconds. Ignored if
1592 variable muxrate is selected. Default is @code{20}.
1594 @item pat_period @var{double}
1595 Maximum time in seconds between PAT/PMT tables.
1597 @item sdt_period @var{double}
1598 Maximum time in seconds between SDT tables.
1600 @item tables_version @var{integer}
1601 Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
1602 This option allows updating stream structure so that standard consumer may
1603 detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
1604 usage) or restart @command{ffmpeg} instance, cyclically changing
1605 @option{tables_version} value:
1608 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1609 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1611 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1612 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1613 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1621 ffmpeg -i file.mpg -c copy \
1622 -mpegts_original_network_id 0x1122 \
1623 -mpegts_transport_stream_id 0x3344 \
1624 -mpegts_service_id 0x5566 \
1625 -mpegts_pmt_start_pid 0x1500 \
1626 -mpegts_start_pid 0x150 \
1627 -metadata service_provider="Some provider" \
1628 -metadata service_name="Some Channel" \
1632 @section mxf, mxf_d10
1638 The muxer options are:
1641 @item store_user_comments @var{bool}
1642 Set if user comments should be stored if available or never.
1643 IRT D-10 does not allow user comments. The default is thus to write them for
1644 mxf but not for mxf_d10
1651 This muxer does not generate any output file, it is mainly useful for
1652 testing or benchmarking purposes.
1654 For example to benchmark decoding with @command{ffmpeg} you can use the
1657 ffmpeg -benchmark -i INPUT -f null out.null
1660 Note that the above command does not read or write the @file{out.null}
1661 file, but specifying the output file is required by the @command{ffmpeg}
1664 Alternatively you can write the command as:
1666 ffmpeg -benchmark -i INPUT -f null -
1672 @item -syncpoints @var{flags}
1673 Change the syncpoint usage in nut:
1675 @item @var{default} use the normal low-overhead seeking aids.
1676 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1677 Use of this option is not recommended, as the resulting files are very damage
1678 sensitive and seeking is not possible. Also in general the overhead from
1679 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1680 all growing data tables, allowing to mux endless streams with limited memory
1681 and without these disadvantages.
1682 @item @var{timestamped} extend the syncpoint with a wallclock field.
1684 The @var{none} and @var{timestamped} flags are experimental.
1685 @item -write_index @var{bool}
1686 Write index at the end, the default is to write an index.
1690 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1695 Ogg container muxer.
1698 @item -page_duration @var{duration}
1699 Preferred page duration, in microseconds. The muxer will attempt to create
1700 pages that are approximately @var{duration} microseconds long. This allows the
1701 user to compromise between seek granularity and container overhead. The default
1702 is 1 second. A value of 0 will fill all segments, making pages as large as
1703 possible. A value of 1 will effectively use 1 packet-per-page in most
1704 situations, giving a small seek granularity at the cost of additional container
1706 @item -serial_offset @var{value}
1707 Serial value from which to set the streams serial number.
1708 Setting it to different and sufficiently large values ensures that the produced
1709 ogg files can be safely chained.
1714 @section segment, stream_segment, ssegment
1716 Basic stream segmenter.
1718 This muxer outputs streams to a number of separate files of nearly
1719 fixed duration. Output filename pattern can be set in a fashion
1720 similar to @ref{image2}, or by using a @code{strftime} template if
1721 the @option{strftime} option is enabled.
1723 @code{stream_segment} is a variant of the muxer used to write to
1724 streaming output formats, i.e. which do not require global headers,
1725 and is recommended for outputting e.g. to MPEG transport stream segments.
1726 @code{ssegment} is a shorter alias for @code{stream_segment}.
1728 Every segment starts with a keyframe of the selected reference stream,
1729 which is set through the @option{reference_stream} option.
1731 Note that if you want accurate splitting for a video file, you need to
1732 make the input key frames correspond to the exact splitting times
1733 expected by the segmenter, or the segment muxer will start the new
1734 segment with the key frame found next after the specified start
1737 The segment muxer works best with a single constant frame rate video.
1739 Optionally it can generate a list of the created segments, by setting
1740 the option @var{segment_list}. The list type is specified by the
1741 @var{segment_list_type} option. The entry filenames in the segment
1742 list are set by default to the basename of the corresponding segment
1745 See also the @ref{hls} muxer, which provides a more specific
1746 implementation for HLS segmentation.
1750 The segment muxer supports the following options:
1753 @item increment_tc @var{1|0}
1754 if set to @code{1}, increment timecode between each segment
1755 If this is selected, the input need to have
1756 a timecode in the first video stream. Default value is
1759 @item reference_stream @var{specifier}
1760 Set the reference stream, as specified by the string @var{specifier}.
1761 If @var{specifier} is set to @code{auto}, the reference is chosen
1762 automatically. Otherwise it must be a stream specifier (see the ``Stream
1763 specifiers'' chapter in the ffmpeg manual) which specifies the
1764 reference stream. The default value is @code{auto}.
1766 @item segment_format @var{format}
1767 Override the inner container format, by default it is guessed by the filename
1770 @item segment_format_options @var{options_list}
1771 Set output format options using a :-separated list of key=value
1772 parameters. Values containing the @code{:} special character must be
1775 @item segment_list @var{name}
1776 Generate also a listfile named @var{name}. If not specified no
1777 listfile is generated.
1779 @item segment_list_flags @var{flags}
1780 Set flags affecting the segment list generation.
1782 It currently supports the following flags:
1785 Allow caching (only affects M3U8 list files).
1788 Allow live-friendly file generation.
1791 @item segment_list_size @var{size}
1792 Update the list file so that it contains at most @var{size}
1793 segments. If 0 the list file will contain all the segments. Default
1796 @item segment_list_entry_prefix @var{prefix}
1797 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1798 By default no prefix is applied.
1800 @item segment_list_type @var{type}
1801 Select the listing format.
1803 The following values are recognized:
1806 Generate a flat list for the created segments, one segment per line.
1809 Generate a list for the created segments, one segment per line,
1810 each line matching the format (comma-separated values):
1812 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1815 @var{segment_filename} is the name of the output file generated by the
1816 muxer according to the provided pattern. CSV escaping (according to
1817 RFC4180) is applied if required.
1819 @var{segment_start_time} and @var{segment_end_time} specify
1820 the segment start and end time expressed in seconds.
1822 A list file with the suffix @code{".csv"} or @code{".ext"} will
1823 auto-select this format.
1825 @samp{ext} is deprecated in favor or @samp{csv}.
1828 Generate an ffconcat file for the created segments. The resulting file
1829 can be read using the FFmpeg @ref{concat} demuxer.
1831 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1832 auto-select this format.
1835 Generate an extended M3U8 file, version 3, compliant with
1836 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1838 A list file with the suffix @code{".m3u8"} will auto-select this format.
1841 If not specified the type is guessed from the list file name suffix.
1843 @item segment_time @var{time}
1844 Set segment duration to @var{time}, the value must be a duration
1845 specification. Default value is "2". See also the
1846 @option{segment_times} option.
1848 Note that splitting may not be accurate, unless you force the
1849 reference stream key-frames at the given time. See the introductory
1850 notice and the examples below.
1852 @item segment_atclocktime @var{1|0}
1853 If set to "1" split at regular clock time intervals starting from 00:00
1854 o'clock. The @var{time} value specified in @option{segment_time} is
1855 used for setting the length of the splitting interval.
1857 For example with @option{segment_time} set to "900" this makes it possible
1858 to create files at 12:00 o'clock, 12:15, 12:30, etc.
1860 Default value is "0".
1862 @item segment_clocktime_offset @var{duration}
1863 Delay the segment splitting times with the specified duration when using
1864 @option{segment_atclocktime}.
1866 For example with @option{segment_time} set to "900" and
1867 @option{segment_clocktime_offset} set to "300" this makes it possible to
1868 create files at 12:05, 12:20, 12:35, etc.
1870 Default value is "0".
1872 @item segment_clocktime_wrap_duration @var{duration}
1873 Force the segmenter to only start a new segment if a packet reaches the muxer
1874 within the specified duration after the segmenting clock time. This way you
1875 can make the segmenter more resilient to backward local time jumps, such as
1876 leap seconds or transition to standard time from daylight savings time.
1878 Default is the maximum possible duration which means starting a new segment
1879 regardless of the elapsed time since the last clock time.
1881 @item segment_time_delta @var{delta}
1882 Specify the accuracy time when selecting the start time for a
1883 segment, expressed as a duration specification. Default value is "0".
1885 When delta is specified a key-frame will start a new segment if its
1886 PTS satisfies the relation:
1888 PTS >= start_time - time_delta
1891 This option is useful when splitting video content, which is always
1892 split at GOP boundaries, in case a key frame is found just before the
1893 specified split time.
1895 In particular may be used in combination with the @file{ffmpeg} option
1896 @var{force_key_frames}. The key frame times specified by
1897 @var{force_key_frames} may not be set accurately because of rounding
1898 issues, with the consequence that a key frame time may result set just
1899 before the specified time. For constant frame rate videos a value of
1900 1/(2*@var{frame_rate}) should address the worst case mismatch between
1901 the specified time and the time set by @var{force_key_frames}.
1903 @item segment_times @var{times}
1904 Specify a list of split points. @var{times} contains a list of comma
1905 separated duration specifications, in increasing order. See also
1906 the @option{segment_time} option.
1908 @item segment_frames @var{frames}
1909 Specify a list of split video frame numbers. @var{frames} contains a
1910 list of comma separated integer numbers, in increasing order.
1912 This option specifies to start a new segment whenever a reference
1913 stream key frame is found and the sequential number (starting from 0)
1914 of the frame is greater or equal to the next value in the list.
1916 @item segment_wrap @var{limit}
1917 Wrap around segment index once it reaches @var{limit}.
1919 @item segment_start_number @var{number}
1920 Set the sequence number of the first segment. Defaults to @code{0}.
1922 @item strftime @var{1|0}
1923 Use the @code{strftime} function to define the name of the new
1924 segments to write. If this is selected, the output segment name must
1925 contain a @code{strftime} function template. Default value is
1928 @item break_non_keyframes @var{1|0}
1929 If enabled, allow segments to start on frames other than keyframes. This
1930 improves behavior on some players when the time between keyframes is
1931 inconsistent, but may make things worse on others, and can cause some oddities
1932 during seeking. Defaults to @code{0}.
1934 @item reset_timestamps @var{1|0}
1935 Reset timestamps at the beginning of each segment, so that each segment
1936 will start with near-zero timestamps. It is meant to ease the playback
1937 of the generated segments. May not work with some combinations of
1938 muxers/codecs. It is set to @code{0} by default.
1940 @item initial_offset @var{offset}
1941 Specify timestamp offset to apply to the output packet timestamps. The
1942 argument must be a time duration specification, and defaults to 0.
1944 @item write_empty_segments @var{1|0}
1945 If enabled, write an empty segment if there are no packets during the period a
1946 segment would usually span. Otherwise, the segment will be filled with the next
1947 packet written. Defaults to @code{0}.
1950 Make sure to require a closed GOP when encoding and to set the GOP
1951 size to fit your segment time constraint.
1953 @subsection Examples
1957 Remux the content of file @file{in.mkv} to a list of segments
1958 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
1959 generated segments to @file{out.list}:
1961 ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
1965 Segment input and set output format options for the output segments:
1967 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
1971 Segment the input file according to the split points specified by the
1972 @var{segment_times} option:
1974 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 out%03d.nut
1978 Use the @command{ffmpeg} @option{force_key_frames}
1979 option to force key frames in the input at the specified location, together
1980 with the segment option @option{segment_time_delta} to account for
1981 possible roundings operated when setting key frame times.
1983 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
1984 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
1986 In order to force key frames on the input file, transcoding is
1990 Segment the input file by splitting the input file according to the
1991 frame numbers sequence specified with the @option{segment_frames} option:
1993 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
1997 Convert the @file{in.mkv} to TS segments using the @code{libx264}
1998 and @code{aac} encoders:
2000 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
2004 Segment the input file, and create an M3U8 live playlist (can be used
2005 as live HLS source):
2007 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
2008 -segment_list_flags +live -segment_time 10 out%03d.mkv
2012 @section smoothstreaming
2014 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
2018 Specify the number of fragments kept in the manifest. Default 0 (keep all).
2020 @item extra_window_size
2021 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
2023 @item lookahead_count
2024 Specify the number of lookahead fragments. Default 2.
2026 @item min_frag_duration
2027 Specify the minimum fragment duration (in microseconds). Default 5000000.
2029 @item remove_at_exit
2030 Specify whether to remove all fragments when finished. Default 0 (do not remove).
2037 The fifo pseudo-muxer allows the separation of encoding and muxing by using
2038 first-in-first-out queue and running the actual muxer in a separate thread. This
2039 is especially useful in combination with the @ref{tee} muxer and can be used to
2040 send data to several destinations with different reliability/writing speed/latency.
2042 API users should be aware that callback functions (interrupt_callback,
2043 io_open and io_close) used within its AVFormatContext must be thread-safe.
2045 The behavior of the fifo muxer if the queue fills up or if the output fails is
2051 output can be transparently restarted with configurable delay between retries
2052 based on real time or time of the processed stream.
2055 encoding can be blocked during temporary failure, or continue transparently
2056 dropping packets in case fifo queue fills up.
2063 Specify the format name. Useful if it cannot be guessed from the
2067 Specify size of the queue (number of packets). Default value is 60.
2070 Specify format options for the underlying muxer. Muxer options can be specified
2071 as a list of @var{key}=@var{value} pairs separated by ':'.
2073 @item drop_pkts_on_overflow @var{bool}
2074 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
2075 rather than blocking the encoder. This makes it possible to continue streaming without
2076 delaying the input, at the cost of omitting part of the stream. By default
2077 this option is set to 0 (false), so in such cases the encoder will be blocked
2078 until the muxer processes some of the packets and none of them is lost.
2080 @item attempt_recovery @var{bool}
2081 If failure occurs, attempt to recover the output. This is especially useful
2082 when used with network output, since it makes it possible to restart streaming transparently.
2083 By default this option is set to 0 (false).
2085 @item max_recovery_attempts
2086 Sets maximum number of successive unsuccessful recovery attempts after which
2087 the output fails permanently. By default this option is set to 0 (unlimited).
2089 @item recovery_wait_time @var{duration}
2090 Waiting time before the next recovery attempt after previous unsuccessful
2091 recovery attempt. Default value is 5 seconds.
2093 @item recovery_wait_streamtime @var{bool}
2094 If set to 0 (false), the real time is used when waiting for the recovery
2095 attempt (i.e. the recovery will be attempted after at least
2096 recovery_wait_time seconds).
2097 If set to 1 (true), the time of the processed stream is taken into account
2098 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
2099 seconds of the stream is omitted).
2100 By default, this option is set to 0 (false).
2102 @item recover_any_error @var{bool}
2103 If set to 1 (true), recovery will be attempted regardless of type of the error
2104 causing the failure. By default this option is set to 0 (false) and in case of
2105 certain (usually permanent) errors the recovery is not attempted even when
2106 @var{attempt_recovery} is set to 1.
2108 @item restart_with_keyframe @var{bool}
2109 Specify whether to wait for the keyframe after recovering from
2110 queue overflow or failure. This option is set to 0 (false) by default.
2114 @subsection Examples
2119 Stream something to rtmp server, continue processing the stream at real-time
2120 rate even in case of temporary failure (network outage) and attempt to recover
2121 streaming every second indefinitely.
2123 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
2124 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
2132 The tee muxer can be used to write the same data to several outputs, such as files or streams.
2133 It can be used, for example, to stream a video over a network and save it to disk at the same time.
2135 It is different from specifying several outputs to the @command{ffmpeg}
2136 command-line tool. With the tee muxer, the audio and video data will be encoded only once.
2137 With conventional multiple outputs, multiple encoding operations in parallel are initiated,
2138 which can be a very expensive process. The tee muxer is not useful when using the libavformat API
2139 directly because it is then possible to feed the same packets to several muxers directly.
2141 Since the tee muxer does not represent any particular output format, ffmpeg cannot auto-select
2142 output streams. So all streams intended for output must be specified using @code{-map}. See
2145 Some encoders may need different options depending on the output format;
2146 the auto-detection of this can not work with the tee muxer, so they need to be explicitly specified.
2147 The main example is the @option{global_header} flag.
2149 The slave outputs are specified in the file name given to the muxer,
2150 separated by '|'. If any of the slave name contains the '|' separator,
2151 leading or trailing spaces or any special character, those must be
2152 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
2153 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
2159 @item use_fifo @var{bool}
2160 If set to 1, slave outputs will be processed in separate threads using the @ref{fifo}
2161 muxer. This allows to compensate for different speed/latency/reliability of
2162 outputs and setup transparent recovery. By default this feature is turned off.
2165 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
2169 Muxer options can be specified for each slave by prepending them as a list of
2170 @var{key}=@var{value} pairs separated by ':', between square brackets. If
2171 the options values contain a special character or the ':' separator, they
2172 must be escaped; note that this is a second level escaping.
2174 The following special options are also recognized:
2177 Specify the format name. Required if it cannot be guessed from the
2180 @item bsfs[/@var{spec}]
2181 Specify a list of bitstream filters to apply to the specified
2184 It is possible to specify to which streams a given bitstream filter
2185 applies, by appending a stream specifier to the option separated by
2186 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
2187 stream specifiers}).
2189 If the stream specifier is not specified, the bitstream filters will be
2190 applied to all streams in the output. This will cause that output operation
2191 to fail if the output contains streams to which the bitstream filter cannot
2192 be applied e.g. @code{h264_mp4toannexb} being applied to an output containing an audio stream.
2194 Options for a bitstream filter must be specified in the form of @code{opt=value}.
2196 Several bitstream filters can be specified, separated by ",".
2198 @item use_fifo @var{bool}
2199 This allows to override tee muxer use_fifo option for individual slave muxer.
2202 This allows to override tee muxer fifo_options for individual slave muxer.
2206 Select the streams that should be mapped to the slave output,
2207 specified by a stream specifier. If not specified, this defaults to
2208 all the mapped streams. This will cause that output operation to fail
2209 if the output format does not accept all mapped streams.
2211 You may use multiple stream specifiers separated by commas (@code{,}) e.g.: @code{a:0,v}
2214 Specify behaviour on output failure. This can be set to either @code{abort} (which is
2215 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
2216 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
2217 will continue without being affected.
2220 @subsection Examples
2224 Encode something and both archive it in a WebM file and stream it
2225 as MPEG-TS over UDP:
2227 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2228 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2232 As above, but continue streaming even if output to local file fails
2233 (for example local drive fills up):
2235 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2236 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2240 Use @command{ffmpeg} to encode the input, and send the output
2241 to three different destinations. The @code{dump_extra} bitstream
2242 filter is used to add extradata information to all the output video
2243 keyframes packets, as requested by the MPEG-TS format. The select
2244 option is applied to @file{out.aac} in order to make it contain only
2247 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2248 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
2252 As above, but select only stream @code{a:1} for the audio output. Note
2253 that a second level escaping must be performed, as ":" is a special
2254 character used to separate options.
2256 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2257 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
2261 @section webm_dash_manifest
2263 WebM DASH Manifest muxer.
2265 This muxer implements the WebM DASH Manifest specification to generate the DASH
2266 manifest XML. It also supports manifest generation for DASH live streams.
2268 For more information see:
2272 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
2274 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
2279 This muxer supports the following options:
2282 @item adaptation_sets
2283 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
2284 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
2285 audio and video streams. Any number of adaptation sets can be added using this option.
2288 Set this to 1 to create a live stream DASH Manifest. Default: 0.
2290 @item chunk_start_index
2291 Start index of the first chunk. This will go in the @samp{startNumber} attribute
2292 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
2294 @item chunk_duration_ms
2295 Duration of each chunk in milliseconds. This will go in the @samp{duration}
2296 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
2298 @item utc_timing_url
2299 URL of the page that will return the UTC timestamp in ISO format. This will go
2300 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
2303 @item time_shift_buffer_depth
2304 Smallest time (in seconds) shifting buffer for which any Representation is
2305 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
2306 attribute of the @samp{MPD} element. Default: 60.
2308 @item minimum_update_period
2309 Minimum update period (in seconds) of the manifest. This will go in the
2310 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
2316 ffmpeg -f webm_dash_manifest -i video1.webm \
2317 -f webm_dash_manifest -i video2.webm \
2318 -f webm_dash_manifest -i audio1.webm \
2319 -f webm_dash_manifest -i audio2.webm \
2320 -map 0 -map 1 -map 2 -map 3 \
2322 -f webm_dash_manifest \
2323 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
2329 WebM Live Chunk Muxer.
2331 This muxer writes out WebM headers and chunks as separate files which can be
2332 consumed by clients that support WebM Live streams via DASH.
2336 This muxer supports the following options:
2339 @item chunk_start_index
2340 Index of the first chunk (defaults to 0).
2343 Filename of the header where the initialization data will be written.
2345 @item audio_chunk_duration
2346 Duration of each audio chunk in milliseconds (defaults to 5000).
2351 ffmpeg -f v4l2 -i /dev/video0 \
2355 -s 640x360 -keyint_min 30 -g 30 \
2357 -header webm_live_video_360.hdr \
2358 -chunk_start_index 1 \
2359 webm_live_video_360_%d.chk \
2364 -header webm_live_audio_128.hdr \
2365 -chunk_start_index 1 \
2366 -audio_chunk_duration 1000 \
2367 webm_live_audio_128_%d.chk