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 -global_sidx @var{global_sidx}
297 Write global SIDX atom. Applicable only for single file, mp4 output, non-streaming mode.
299 @item -dash_segment_type @var{dash_segment_type}
302 If this flag is set, the dash segment files format will be selected based on the stream codec. This is the default mode.
305 If this flag is set, the dash segment files will be in in ISOBMFF format.
308 If this flag is set, the dash segment files will be in in WebM format.
310 @item -ignore_io_errors @var{ignore_io_errors}
311 Ignore IO errors during open and write. Useful for long-duration runs with network output.
313 @item -lhls @var{lhls}
314 Enable Low-latency HLS(LHLS). Adds #EXT-X-PREFETCH tag with current segment's URI.
315 Apple doesn't have an official spec for LHLS. Meanwhile hls.js player folks are
316 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
317 This option will also try to comply with the above open spec, till Apple's spec officially supports it.
318 Applicable only when @var{streaming} and @var{hls_playlist} options are enabled.
319 This is an experimental feature.
321 @item -master_m3u8_publish_rate @var{master_m3u8_publish_rate}
322 Publish master playlist repeatedly every after specified number of segment intervals.
329 Per-packet CRC (Cyclic Redundancy Check) testing format.
331 This muxer computes and prints the Adler-32 CRC for each audio
332 and video packet. By default audio frames are converted to signed
333 16-bit raw audio and video frames to raw video before computing the
336 The output of the muxer consists of a line for each audio and video
339 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
342 @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
347 For example to compute the CRC of the audio and video frames in
348 @file{INPUT}, converted to raw audio and video packets, and store it
349 in the file @file{out.crc}:
351 ffmpeg -i INPUT -f framecrc out.crc
354 To print the information to stdout, use the command:
356 ffmpeg -i INPUT -f framecrc -
359 With @command{ffmpeg}, you can select the output format to which the
360 audio and video frames are encoded before computing the CRC for each
361 packet by specifying the audio and video codec. For example, to
362 compute the CRC of each decoded input audio frame converted to PCM
363 unsigned 8-bit and of each decoded input video frame converted to
364 MPEG-2 video, use the command:
366 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
369 See also the @ref{crc} muxer.
374 Per-packet hash testing format.
376 This muxer computes and prints a cryptographic hash for each audio
377 and video packet. This can be used for packet-by-packet equality
378 checks without having to individually do a binary comparison on each.
380 By default audio frames are converted to signed 16-bit raw audio and
381 video frames to raw video before computing the hash, but the output
382 of explicit conversions to other codecs can also be used. It uses the
383 SHA-256 cryptographic hash function by default, but supports several
386 The output of the muxer consists of a line for each audio and video
389 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
392 @var{hash} is a hexadecimal number representing the computed hash
396 @item hash @var{algorithm}
397 Use the cryptographic hash function specified by the string @var{algorithm}.
398 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
399 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
400 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
401 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
407 To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
408 converted to raw audio and video packets, and store it in the file
411 ffmpeg -i INPUT -f framehash out.sha256
414 To print the information to stdout, using the MD5 hash function, use
417 ffmpeg -i INPUT -f framehash -hash md5 -
420 See also the @ref{hash} muxer.
425 Per-packet MD5 testing format.
427 This is a variant of the @ref{framehash} muxer. Unlike that muxer,
428 it defaults to using the MD5 hash function.
432 To compute the MD5 hash of the audio and video frames in @file{INPUT},
433 converted to raw audio and video packets, and store it in the file
436 ffmpeg -i INPUT -f framemd5 out.md5
439 To print the information to stdout, use the command:
441 ffmpeg -i INPUT -f framemd5 -
444 See also the @ref{framehash} and @ref{md5} muxers.
451 It accepts the following options:
455 Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
456 for looping indefinitely (default).
459 Force the delay (expressed in centiseconds) after the last frame. Each frame
460 ends with a delay until the next frame. The default is @code{-1}, which is a
461 special value to tell the muxer to re-use the previous delay. In case of a
462 loop, you might want to customize this value to mark a pause for instance.
465 For example, to encode a gif looping 10 times, with a 5 seconds delay between
468 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
471 Note 1: if you wish to extract the frames into separate GIF files, you need to
472 force the @ref{image2} muxer:
474 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
477 Note 2: the GIF format has a very large time base: the delay between two frames
478 can therefore not be smaller than one centi second.
485 This muxer computes and prints a cryptographic hash of all the input
486 audio and video frames. This can be used for equality checks without
487 having to do a complete binary comparison.
489 By default audio frames are converted to signed 16-bit raw audio and
490 video frames to raw video before computing the hash, but the output
491 of explicit conversions to other codecs can also be used. Timestamps
492 are ignored. It uses the SHA-256 cryptographic hash function by default,
493 but supports several other algorithms.
495 The output of the muxer consists of a single line of the form:
496 @var{algo}=@var{hash}, where @var{algo} is a short string representing
497 the hash function used, and @var{hash} is a hexadecimal number
498 representing the computed hash.
501 @item hash @var{algorithm}
502 Use the cryptographic hash function specified by the string @var{algorithm}.
503 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
504 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
505 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
506 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
512 To compute the SHA-256 hash of the input converted to raw audio and
513 video, and store it in the file @file{out.sha256}:
515 ffmpeg -i INPUT -f hash out.sha256
518 To print an MD5 hash to stdout use the command:
520 ffmpeg -i INPUT -f hash -hash md5 -
523 See also the @ref{framehash} muxer.
528 Apple HTTP Live Streaming muxer that segments MPEG-TS according to
529 the HTTP Live Streaming (HLS) specification.
531 It creates a playlist file, and one or more segment files. The output filename
532 specifies the playlist filename.
534 By default, the muxer creates a file for each segment produced. These files
535 have the same name as the playlist, followed by a sequential number and a
538 Make sure to require a closed GOP when encoding and to set the GOP
539 size to fit your segment time constraint.
541 For example, to convert an input file with @command{ffmpeg}:
543 ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
545 This example will produce the playlist, @file{out.m3u8}, and segment files:
546 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
548 See also the @ref{segment} muxer, which provides a more generic and
549 flexible implementation of a segmenter, and can be used to perform HLS
554 This muxer supports the following options:
557 @item hls_init_time @var{seconds}
558 Set the initial target segment length in seconds. Default value is @var{0}.
559 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
560 After the initial playlist is filled @command{ffmpeg} will cut segments
561 at duration equal to @code{hls_time}
563 @item hls_time @var{seconds}
564 Set the target segment length in seconds. Default value is 2.
565 Segment will be cut on the next key frame after this time has passed.
567 @item hls_list_size @var{size}
568 Set the maximum number of playlist entries. If set to 0 the list file
569 will contain all the segments. Default value is 5.
571 @item hls_delete_threshold @var{size}
572 Set the number of unreferenced segments to keep on disk before @code{hls_flags delete_segments}
573 deletes them. Increase this to allow continue clients to download segments which
574 were recently referenced in the playlist. Default value is 1, meaning segments older than
575 @code{hls_list_size+1} will be deleted.
577 @item hls_ts_options @var{options_list}
578 Set output format options using a :-separated list of key=value
579 parameters. Values containing @code{:} special characters must be
582 @item hls_wrap @var{wrap}
583 This is a deprecated option, you can use @code{hls_list_size}
584 and @code{hls_flags delete_segments} instead it
586 This option is useful to avoid to fill the disk with many segment
587 files, and limits the maximum number of segment files written to disk
591 @item hls_start_number_source
592 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
593 Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
594 segment and subtitle filenames. In any case, if @code{hls_flags append_list}
595 is set and read playlist sequence number is greater than the specified start sequence number,
596 then that value will be used as start value.
598 It accepts the following values:
602 @item generic (default)
603 Set the starting sequence numbers according to @var{start_number} option value.
606 The start number will be the seconds since epoch (1970-01-01 00:00:00)
609 The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
613 @item start_number @var{number}
614 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
615 when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
616 Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
619 @item hls_allow_cache @var{allowcache}
620 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
622 @item hls_base_url @var{baseurl}
623 Append @var{baseurl} to every entry in the playlist.
624 Useful to generate playlists with absolute paths.
626 Note that the playlist sequence number must be unique for each segment
627 and it is not to be confused with the segment filename sequence number
628 which can be cyclic, for example if the @option{wrap} option is
631 @item hls_segment_filename @var{filename}
632 Set the segment filename. Unless @code{hls_flags single_file} is set,
633 @var{filename} is used as a string format with the segment number:
635 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
637 This example will produce the playlist, @file{out.m3u8}, and segment files:
638 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
640 @var{filename} may contain full path or relative path specification,
641 but only the file name part without any path info will be contained in the m3u8 segment list.
642 Should a relative path be specified, the path of the created segment
643 files will be relative to the current working directory.
644 When strftime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
646 When @code{var_stream_map} is set with two or more variant streams, the
647 @var{filename} pattern must contain the string "%v", this string specifies
648 the position of variant stream index in the generated segment file names.
650 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
651 -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" \
652 -hls_segment_filename 'file_%v_%03d.ts' out_%v.m3u8
654 This example will produce the playlists segment file sets:
655 @file{file_0_000.ts}, @file{file_0_001.ts}, @file{file_0_002.ts}, etc. and
656 @file{file_1_000.ts}, @file{file_1_001.ts}, @file{file_1_002.ts}, etc.
658 The string "%v" may be present in the filename or in the last directory name
659 containing the file, but only in one of them. (Additionally, %v may appear multiple times in the last
660 sub-directory or filename.) If the string %v is present in the directory name, then
661 sub-directories are created after expanding the directory name pattern. This
662 enables creation of segments corresponding to different variant streams in
665 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
666 -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" \
667 -hls_segment_filename 'vs%v/file_%03d.ts' vs%v/out.m3u8
669 This example will produce the playlists segment file sets:
670 @file{vs0/file_000.ts}, @file{vs0/file_001.ts}, @file{vs0/file_002.ts}, etc. and
671 @file{vs1/file_000.ts}, @file{vs1/file_001.ts}, @file{vs1/file_002.ts}, etc.
674 Same as strftime option, will be deprecated.
677 Use strftime() on @var{filename} to expand the segment filename with localtime.
678 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
679 hls_flag and %%d will be the specifier.
681 ffmpeg -i in.nut -strftime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
683 This example will produce the playlist, @file{out.m3u8}, and segment files:
684 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
685 Note: On some systems/environments, the @code{%s} specifier is not available. See
686 @code{strftime()} documentation.
688 ffmpeg -i in.nut -strftime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
690 This example will produce the playlist, @file{out.m3u8}, and segment files:
691 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
693 @item use_localtime_mkdir
694 Same as strftime_mkdir option, will be deprecated .
697 Used together with -strftime_mkdir, it will create all subdirectories which
698 is expanded in @var{filename}.
700 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y%m%d/file-%Y%m%d-%s.ts' out.m3u8
702 This example will create a directory 201560215 (if it does not exist), and then
703 produce the playlist, @file{out.m3u8}, and segment files:
704 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
707 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y/%m/%d/file-%Y%m%d-%s.ts' out.m3u8
709 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
710 produce the playlist, @file{out.m3u8}, and segment files:
711 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
714 @item hls_key_info_file @var{key_info_file}
715 Use the information in @var{key_info_file} for segment encryption. The first
716 line of @var{key_info_file} specifies the key URI written to the playlist. The
717 key URL is used to access the encryption key during playback. The second line
718 specifies the path to the key file used to obtain the key during the encryption
719 process. The key file is read as a single packed array of 16 octets in binary
720 format. The optional third line specifies the initialization vector (IV) as a
721 hexadecimal string to be used instead of the segment sequence number (default)
722 for encryption. Changes to @var{key_info_file} will result in segment
723 encryption with the new key/IV and an entry in the playlist for the new key
724 URI/IV if @code{hls_flags periodic_rekey} is enabled.
726 Key info file format:
735 http://server/file.key
740 Example key file paths:
748 0123456789ABCDEF0123456789ABCDEF
751 Key info file example:
753 http://server/file.key
755 0123456789ABCDEF0123456789ABCDEF
758 Example shell script:
762 openssl rand 16 > file.key
763 echo $BASE_URL/file.key > file.keyinfo
764 echo file.key >> file.keyinfo
765 echo $(openssl rand -hex 16) >> file.keyinfo
766 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
767 -hls_key_info_file file.keyinfo out.m3u8
770 @item -hls_enc @var{enc}
771 Enable (1) or disable (0) the AES128 encryption.
772 When enabled every segment generated is encrypted and the encryption key
773 is saved as @var{playlist name}.key.
775 @item -hls_enc_key @var{key}
776 Hex-coded 16byte key to encrypt the segments, by default it
777 is randomly generated.
779 @item -hls_enc_key_url @var{keyurl}
780 If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
783 @item -hls_enc_iv @var{iv}
784 Hex-coded 16byte initialization vector for every segment instead
785 of the autogenerated ones.
787 @item hls_segment_type @var{flags}
792 Output segment files in MPEG-2 Transport Stream format. This is
793 compatible with all HLS versions.
796 Output segment files in fragmented MP4 format, similar to MPEG-DASH.
797 fmp4 files may be used in HLS version 7 and above.
801 @item hls_fmp4_init_filename @var{filename}
802 Set filename to the fragment files header file, default filename is @file{init.mp4}.
804 When @code{var_stream_map} is set with two or more variant streams, the
805 @var{filename} pattern must contain the string "%v", this string specifies
806 the position of variant stream index in the generated init file names.
807 The string "%v" may be present in the filename or in the last directory name
808 containing the file. If the string is present in the directory name, then
809 sub-directories are created after expanding the directory name pattern. This
810 enables creation of init files corresponding to different variant streams in
813 @item hls_flags @var{flags}
818 If this flag is set, the muxer will store all segments in a single MPEG-TS
819 file, and will use byte ranges in the playlist. HLS playlists generated with
820 this way will have the version number 4.
823 ffmpeg -i in.nut -hls_flags single_file out.m3u8
825 Will produce the playlist, @file{out.m3u8}, and a single segment file,
828 @item delete_segments
829 Segment files removed from the playlist are deleted after a period of time
830 equal to the duration of the segment plus the duration of the playlist.
833 Append new segments into the end of old segment list,
834 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
836 @item round_durations
837 Round the duration info in the playlist file segment info to integer
838 values, instead of using floating point.
841 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
842 first segment's information.
845 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
848 The file specified by @code{hls_key_info_file} will be checked periodically and
849 detect updates to the encryption info. Be sure to replace this file atomically,
850 including the file containing the AES encryption key.
852 @item independent_segments
853 Add the @code{#EXT-X-INDEPENDENT-SEGMENTS} to playlists that has video segments
854 and when all the segments of that playlist are guaranteed to start with a Key frame.
857 Add the @code{#EXT-X-I-FRAMES-ONLY} to playlists that has video segments
858 and can play only I-frames in the @code{#EXT-X-BYTERANGE} mode.
861 Allow segments to start on frames other than keyframes. This improves
862 behavior on some players when the time between keyframes is inconsistent,
863 but may make things worse on others, and can cause some oddities during
864 seeking. This flag should be used with the @code{hls_time} option.
866 @item program_date_time
867 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
869 @item second_level_segment_index
870 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
871 besides date/time values when strftime is on.
872 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
874 @item second_level_segment_size
875 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
876 expression besides date/time values when strftime is on.
877 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
879 @item second_level_segment_duration
880 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
881 expression besides date/time values when strftime is on.
882 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
885 ffmpeg -i sample.mpeg \
886 -f hls -hls_time 3 -hls_list_size 5 \
887 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
888 -strftime 1 -strftime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
890 This will produce segments like this:
891 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
894 Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
895 serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
896 before they have been added to the m3u8 playlist.
900 @item hls_playlist_type event
901 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
902 @option{hls_list_size} to 0; the playlist can only be appended to.
904 @item hls_playlist_type vod
905 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
906 @option{hls_list_size} to 0; the playlist must not change.
909 Use the given HTTP method to create the hls files.
911 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
913 This example will upload all the mpegts segment files to the HTTP
914 server using the HTTP PUT method, and update the m3u8 files every
915 @code{refresh} times using the same method.
916 Note that the HTTP server must support the given method for uploading
919 @item http_user_agent
920 Override User-Agent field in HTTP header. Applicable only for HTTP output.
923 Map string which specifies how to group the audio, video and subtitle streams
924 into different variant streams. The variant stream groups are separated
926 Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
927 the keys to specify audio, video and subtitle streams respectively.
928 Allowed values are 0 to 9 (limited just based on practical usage).
930 When there are two or more variant streams, the output filename pattern must
931 contain the string "%v", this string specifies the position of variant stream
932 index in the output media playlist filenames. The string "%v" may be present in
933 the filename or in the last directory name containing the file. If the string is
934 present in the directory name, then sub-directories are created after expanding
935 the directory name pattern. This enables creation of variant streams in
939 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
940 -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" \
941 http://example.com/live/out_%v.m3u8
943 This example creates two hls variant streams. The first variant stream will
944 contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
945 second variant stream will contain video stream of bitrate 256k and audio
946 stream of bitrate 32k. Here, two media playlist with file names out_0.m3u8 and
947 out_1.m3u8 will be created. If you want something meaningful text instead of indexes
948 in result names, you may specify names for each or some of the variants
949 as in the following example.
953 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
954 -map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0,name:my_hd v:1,a:1,name:my_sd" \
955 http://example.com/live/out_%v.m3u8
958 This example creates two hls variant streams as in the previous one.
959 But here, the two media playlist with file names out_my_hd.m3u8 and
960 out_my_sd.m3u8 will be created.
963 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
964 -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
965 http://example.com/live/out_%v.m3u8
967 This example creates three hls variant streams. The first variant stream will
968 be a video only stream with video bitrate 1000k, the second variant stream will
969 be an audio only stream with bitrate 64k and the third variant stream will be a
970 video only stream with bitrate 256k. Here, three media playlist with file names
971 out_0.m3u8, out_1.m3u8 and out_2.m3u8 will be created.
973 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
974 -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" \
975 http://example.com/live/vs_%v/out.m3u8
977 This example creates the variant streams in subdirectories. Here, the first
978 media playlist is created at @file{http://example.com/live/vs_0/out.m3u8} and
979 the second one at @file{http://example.com/live/vs_1/out.m3u8}.
981 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k \
982 -map 0:a -map 0:a -map 0:v -map 0:v -f hls \
983 -var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
984 -master_pl_name master.m3u8 \
985 http://example.com/live/out_%v.m3u8
987 This example creates two audio only and two video only variant streams. In
988 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
989 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
990 and they are mapped to the two video only variant streams with audio group names
991 'aud_low' and 'aud_high'.
993 By default, a single hls variant containing all the encoded streams is created.
996 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
997 -map 0:a -map 0:a -map 0:v -f hls \
998 -var_stream_map "a:0,agroup:aud_low,default:yes a:1,agroup:aud_low v:0,agroup:aud_low" \
999 -master_pl_name master.m3u8 \
1000 http://example.com/live/out_%v.m3u8
1002 This example creates two audio only and one video only variant streams. In
1003 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1004 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1005 and they are mapped to the one video only variant streams with audio group name
1006 'aud_low', and the audio group have default stat is NO or YES.
1008 By default, a single hls variant containing all the encoded streams is created.
1011 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
1012 -map 0:a -map 0:a -map 0:v -f hls \
1013 -var_stream_map "a:0,agroup:aud_low,default:yes,language:ENG a:1,agroup:aud_low,language:CHN v:0,agroup:aud_low" \
1014 -master_pl_name master.m3u8 \
1015 http://example.com/live/out_%v.m3u8
1017 This example creates two audio only and one video only variant streams. In
1018 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1019 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1020 and they are mapped to the one video only variant streams with audio group name
1021 'aud_low', and the audio group have default stat is NO or YES, and one audio
1022 have and language is named ENG, the other audio language is named CHN.
1024 By default, a single hls variant containing all the encoded streams is created.
1027 Map string which specifies different closed captions groups and their
1028 attributes. The closed captions stream groups are separated by space.
1029 Expected string format is like this
1030 "ccgroup:<group name>,instreamid:<INSTREAM-ID>,language:<language code> ....".
1031 'ccgroup' and 'instreamid' are mandatory attributes. 'language' is an optional
1033 The closed captions groups configured using this option are mapped to different
1034 variant streams by providing the same 'ccgroup' name in the
1035 @code{var_stream_map} string. If @code{var_stream_map} is not set, then the
1036 first available ccgroup in @code{cc_stream_map} is mapped to the output variant
1037 stream. The examples for these two use cases are given below.
1040 ffmpeg -re -i in.ts -b:v 1000k -b:a 64k -a53cc 1 -f hls \
1041 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en" \
1042 -master_pl_name master.m3u8 \
1043 http://example.com/live/out.m3u8
1045 This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=CLOSED-CAPTIONS} in
1046 the master playlist with group name 'cc', language 'en' (english) and
1047 INSTREAM-ID 'CC1'. Also, it adds @code{CLOSED-CAPTIONS} attribute with group
1048 name 'cc' for the output variant stream.
1050 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1051 -a53cc:0 1 -a53cc:1 1\
1052 -map 0:v -map 0:a -map 0:v -map 0:a -f hls \
1053 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en ccgroup:cc,instreamid:CC2,language:sp" \
1054 -var_stream_map "v:0,a:0,ccgroup:cc v:1,a:1,ccgroup:cc" \
1055 -master_pl_name master.m3u8 \
1056 http://example.com/live/out_%v.m3u8
1058 This example adds two @code{#EXT-X-MEDIA} tags with @code{TYPE=CLOSED-CAPTIONS} in
1059 the master playlist for the INSTREAM-IDs 'CC1' and 'CC2'. Also, it adds
1060 @code{CLOSED-CAPTIONS} attribute with group name 'cc' for the two output variant
1063 @item master_pl_name
1064 Create HLS master playlist with the given name.
1067 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
1069 This example creates HLS master playlist with name master.m3u8 and it is
1070 published at http://example.com/live/
1072 @item master_pl_publish_rate
1073 Publish master play list repeatedly every after specified number of segment intervals.
1076 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
1077 -hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
1080 This example creates HLS master playlist with name master.m3u8 and keep
1081 publishing it repeatedly every after 30 segments i.e. every after 60s.
1083 @item http_persistent
1084 Use persistent HTTP connections. Applicable only for HTTP output.
1087 Set timeout for socket I/O operations. Applicable only for HTTP output.
1089 @item -ignore_io_errors
1090 Ignore IO errors during open, write and delete. Useful for long-duration runs with network output.
1093 Set custom HTTP headers, can override built in default headers. Applicable only for HTTP output.
1102 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
1106 Size cannot exceed 256 pixels in any dimension
1109 Only BMP and PNG images can be stored
1112 If a BMP image is used, it must be one of the following pixel formats:
1114 BMP Bit Depth FFmpeg Pixel Format
1124 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
1127 If a PNG image is used, it must use the rgba pixel format
1135 The image file muxer writes video frames to image files.
1137 The output filenames are specified by a pattern, which can be used to
1138 produce sequentially numbered series of files.
1139 The pattern may contain the string "%d" or "%0@var{N}d", this string
1140 specifies the position of the characters representing a numbering in
1141 the filenames. If the form "%0@var{N}d" is used, the string
1142 representing the number in each filename is 0-padded to @var{N}
1143 digits. The literal character '%' can be specified in the pattern with
1146 If the pattern contains "%d" or "%0@var{N}d", the first filename of
1147 the file list specified will contain the number 1, all the following
1148 numbers will be sequential.
1150 The pattern may contain a suffix which is used to automatically
1151 determine the format of the image files to write.
1153 For example the pattern "img-%03d.bmp" will specify a sequence of
1154 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
1155 @file{img-010.bmp}, etc.
1156 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
1157 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
1160 @subsection Examples
1162 The following example shows how to use @command{ffmpeg} for creating a
1163 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
1164 taking one image every second from the input video:
1166 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
1169 Note that with @command{ffmpeg}, if the format is not specified with the
1170 @code{-f} option and the output filename specifies an image file
1171 format, the image2 muxer is automatically selected, so the previous
1172 command can be written as:
1174 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
1177 Note also that the pattern must not necessarily contain "%d" or
1178 "%0@var{N}d", for example to create a single image file
1179 @file{img.jpeg} from the start of the input video you can employ the command:
1181 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
1184 The @option{strftime} option allows you to expand the filename with
1185 date and time information. Check the documentation of
1186 the @code{strftime()} function for the syntax.
1188 For example to generate image files from the @code{strftime()}
1189 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
1192 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
1195 You can set the file name with current frame's PTS:
1197 ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
1204 If set to 1, expand the filename with pts from pkt->pts.
1208 Start the sequence from the specified number. Default value is 1.
1211 If set to 1, the filename will always be interpreted as just a
1212 filename, not a pattern, and the corresponding file will be continuously
1213 overwritten with new images. Default value is 0.
1216 If set to 1, expand the filename with date and time information from
1217 @code{strftime()}. Default value is 0.
1220 The image muxer supports the .Y.U.V image file format. This format is
1221 special in that that each image frame consists of three files, for
1222 each of the YUV420P components. To read or write this image file format,
1223 specify the name of the '.Y' file. The muxer will automatically open the
1224 '.U' and '.V' files as required.
1228 Matroska container muxer.
1230 This muxer implements the matroska and webm container specs.
1232 @subsection Metadata
1234 The recognized metadata settings in this muxer are:
1238 Set title name provided to a single track.
1241 Specify the language of the track in the Matroska languages form.
1243 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
1244 639-2/B) form (like "fre" for French), or a language code mixed with a
1245 country code for specialities in languages (like "fre-ca" for Canadian
1249 Set stereo 3D video layout of two views in a single video track.
1251 The following values are recognized:
1256 Both views are arranged side by side, Left-eye view is on the left
1258 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
1260 Both views are arranged in top-bottom orientation, Left-eye view is on top
1261 @item checkerboard_rl
1262 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
1263 @item checkerboard_lr
1264 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
1265 @item row_interleaved_rl
1266 Each view is constituted by a row based interleaving, Right-eye view is first row
1267 @item row_interleaved_lr
1268 Each view is constituted by a row based interleaving, Left-eye view is first row
1269 @item col_interleaved_rl
1270 Both views are arranged in a column based interleaving manner, Right-eye view is first column
1271 @item col_interleaved_lr
1272 Both views are arranged in a column based interleaving manner, Left-eye view is first column
1273 @item anaglyph_cyan_red
1274 All frames are in anaglyph format viewable through red-cyan filters
1276 Both views are arranged side by side, Right-eye view is on the left
1277 @item anaglyph_green_magenta
1278 All frames are in anaglyph format viewable through green-magenta filters
1280 Both eyes laced in one Block, Left-eye view is first
1282 Both eyes laced in one Block, Right-eye view is first
1286 For example a 3D WebM clip can be created using the following command line:
1288 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
1293 This muxer supports the following options:
1296 @item reserve_index_space
1297 By default, this muxer writes the index for seeking (called cues in Matroska
1298 terms) at the end of the file, because it cannot know in advance how much space
1299 to leave for the index at the beginning of the file. However for some use cases
1300 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
1301 index at the beginning of the file.
1303 If this option is set to a non-zero value, the muxer will reserve a given amount
1304 of space in the file header and then try to write the cues there when the muxing
1305 finishes. If the available space does not suffice, muxing will fail. A safe size
1306 for most use cases should be about 50kB per hour of video.
1308 Note that cues are only written if the output is seekable and this option will
1309 have no effect if it is not.
1317 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
1318 defaults to using the MD5 hash function.
1320 @subsection Examples
1322 To compute the MD5 hash of the input converted to raw
1323 audio and video, and store it in the file @file{out.md5}:
1325 ffmpeg -i INPUT -f md5 out.md5
1328 You can print the MD5 to stdout with the command:
1330 ffmpeg -i INPUT -f md5 -
1333 See also the @ref{hash} and @ref{framemd5} muxers.
1335 @section mov, mp4, ismv
1337 MOV/MP4/ISMV (Smooth Streaming) muxer.
1339 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
1340 file has all the metadata about all packets stored in one location
1341 (written at the end of the file, it can be moved to the start for
1342 better playback by adding @var{faststart} to the @var{movflags}, or
1343 using the @command{qt-faststart} tool). A fragmented
1344 file consists of a number of fragments, where packets and metadata
1345 about these packets are stored together. Writing a fragmented
1346 file has the advantage that the file is decodable even if the
1347 writing is interrupted (while a normal MOV/MP4 is undecodable if
1348 it is not properly finished), and it requires less memory when writing
1349 very long files (since writing normal MOV/MP4 files stores info about
1350 every single packet in memory until the file is closed). The downside
1351 is that it is less compatible with other applications.
1355 Fragmentation is enabled by setting one of the AVOptions that define
1356 how to cut the file into fragments:
1359 @item -moov_size @var{bytes}
1360 Reserves space for the moov atom at the beginning of the file instead of placing the
1361 moov atom at the end. If the space reserved is insufficient, muxing will fail.
1362 @item -movflags frag_keyframe
1363 Start a new fragment at each video keyframe.
1364 @item -frag_duration @var{duration}
1365 Create fragments that are @var{duration} microseconds long.
1366 @item -frag_size @var{size}
1367 Create fragments that contain up to @var{size} bytes of payload data.
1368 @item -movflags frag_custom
1369 Allow the caller to manually choose when to cut fragments, by
1370 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
1371 the packets written so far. (This is only useful with other
1372 applications integrating libavformat, not from @command{ffmpeg}.)
1373 @item -min_frag_duration @var{duration}
1374 Don't create fragments that are shorter than @var{duration} microseconds long.
1377 If more than one condition is specified, fragments are cut when
1378 one of the specified conditions is fulfilled. The exception to this is
1379 @code{-min_frag_duration}, which has to be fulfilled for any of the other
1380 conditions to apply.
1382 Additionally, the way the output file is written can be adjusted
1383 through a few other options:
1386 @item -movflags empty_moov
1387 Write an initial moov atom directly at the start of the file, without
1388 describing any samples in it. Generally, an mdat/moov pair is written
1389 at the start of the file, as a normal MOV/MP4 file, containing only
1390 a short portion of the file. With this option set, there is no initial
1391 mdat atom, and the moov atom only describes the tracks but has
1394 This option is implicitly set when writing ismv (Smooth Streaming) files.
1395 @item -movflags separate_moof
1396 Write a separate moof (movie fragment) atom for each track. Normally,
1397 packets for all tracks are written in a moof atom (which is slightly
1398 more efficient), but with this option set, the muxer writes one moof/mdat
1399 pair for each track, making it easier to separate tracks.
1401 This option is implicitly set when writing ismv (Smooth Streaming) files.
1402 @item -movflags skip_sidx
1403 Skip writing of sidx atom. When bitrate overhead due to sidx atom is high,
1404 this option could be used for cases where sidx atom is not mandatory.
1405 When global_sidx flag is enabled, this option will be ignored.
1406 @item -movflags faststart
1407 Run a second pass moving the index (moov atom) to the beginning of the file.
1408 This operation can take a while, and will not work in various situations such
1409 as fragmented output, thus it is not enabled by default.
1410 @item -movflags rtphint
1411 Add RTP hinting tracks to the output file.
1412 @item -movflags disable_chpl
1413 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
1414 and a QuickTime chapter track are written to the file. With this option
1415 set, only the QuickTime chapter track will be written. Nero chapters can
1416 cause failures when the file is reprocessed with certain tagging programs, like
1417 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
1418 @item -movflags omit_tfhd_offset
1419 Do not write any absolute base_data_offset in tfhd atoms. This avoids
1420 tying fragments to absolute byte positions in the file/streams.
1421 @item -movflags default_base_moof
1422 Similarly to the omit_tfhd_offset, this flag avoids writing the
1423 absolute base_data_offset field in tfhd atoms, but does so by using
1424 the new default-base-is-moof flag instead. This flag is new from
1425 14496-12:2012. This may make the fragments easier to parse in certain
1426 circumstances (avoiding basing track fragment location calculations
1427 on the implicit end of the previous track fragment).
1429 Specify @code{on} to force writing a timecode track, @code{off} to disable it
1430 and @code{auto} to write a timecode track only for mov and mp4 output (default).
1431 @item -movflags negative_cts_offsets
1432 Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
1433 be negative. This enables the initial sample to have DTS/CTS of zero, and
1434 reduces the need for edit lists for some cases such as video tracks with
1435 B-frames. Additionally, eases conformance with the DASH-IF interoperability
1438 This option is implicitly set when writing ismv (Smooth Streaming) files.
1440 Write producer time reference box (PRFT) with a specified time source for the
1441 NTP field in the PRFT box. Set value as @samp{wallclock} to specify timesource
1442 as wallclock time and @samp{pts} to specify timesource as input packets' PTS
1445 Setting value to @samp{pts} is applicable only for a live encoding use case,
1446 where PTS values are set as as wallclock time at the source. For example, an
1447 encoding use case with decklink capture source where @option{video_pts} and
1448 @option{audio_pts} are set to @samp{abs_wallclock}.
1453 Smooth Streaming content can be pushed in real time to a publishing
1454 point on IIS with this muxer. Example:
1456 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
1459 @subsection Audible AAX
1461 Audible AAX files are encrypted M4B files, and they can be decrypted by specifying a 4 byte activation secret.
1463 ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
1468 The MP3 muxer writes a raw MP3 stream with the following optional features:
1471 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
1472 2.4 are supported, the @code{id3v2_version} private option controls which one is
1473 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
1476 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
1477 The pictures are supplied to the muxer in form of a video stream with a single
1478 packet. There can be any number of those streams, each will correspond to a
1479 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
1480 to APIC @var{description} and @var{picture type} respectively. See
1481 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
1483 Note that the APIC frames must be written at the beginning, so the muxer will
1484 buffer the audio frames until it gets all the pictures. It is therefore advised
1485 to provide the pictures as soon as possible to avoid excessive buffering.
1488 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
1489 default, but will be written only if the output is seekable. The
1490 @code{write_xing} private option can be used to disable it. The frame contains
1491 various information that may be useful to the decoder, like the audio duration
1495 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1496 enabled with the @code{write_id3v1} private option, but as its capabilities are
1497 very limited, its usage is not recommended.
1502 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1504 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1507 To attach a picture to an mp3 file select both the audio and the picture stream
1510 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1511 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1514 Write a "clean" MP3 without any extra features:
1516 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1521 MPEG transport stream muxer.
1523 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1525 The recognized metadata settings in mpegts muxer are @code{service_provider}
1526 and @code{service_name}. If they are not set the default for
1527 @code{service_provider} is @samp{FFmpeg} and the default for
1528 @code{service_name} is @samp{Service01}.
1532 The muxer options are:
1535 @item mpegts_transport_stream_id @var{integer}
1536 Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
1537 Default is @code{0x0001}.
1539 @item mpegts_original_network_id @var{integer}
1540 Set the @samp{original_network_id}. This is unique identifier of a
1541 network in DVB. Its main use is in the unique identification of a service
1542 through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
1545 @item mpegts_service_id @var{integer}
1546 Set the @samp{service_id}, also known as program in DVB. Default is
1549 @item mpegts_service_type @var{integer}
1550 Set the program @samp{service_type}. Default is @code{digital_tv}.
1551 Accepts the following options:
1554 Any hexadecimal value between @code{0x01} and @code{0xff} as defined in
1559 Digital Radio service.
1562 @item advanced_codec_digital_radio
1563 Advanced Codec Digital Radio service.
1564 @item mpeg2_digital_hdtv
1565 MPEG2 Digital HDTV service.
1566 @item advanced_codec_digital_sdtv
1567 Advanced Codec Digital SDTV service.
1568 @item advanced_codec_digital_hdtv
1569 Advanced Codec Digital HDTV service.
1572 @item mpegts_pmt_start_pid @var{integer}
1573 Set the first PID for PMT. Default is @code{0x1000}. Max is @code{0x1f00}.
1575 @item mpegts_start_pid @var{integer}
1576 Set the first PID for data packets. Default is @code{0x0100}. Max is
1579 @item mpegts_m2ts_mode @var{boolean}
1580 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
1583 @item muxrate @var{integer}
1584 Set a constant muxrate. Default is VBR.
1586 @item pes_payload_size @var{integer}
1587 Set minimum PES packet payload in bytes. Default is @code{2930}.
1589 @item mpegts_flags @var{flags}
1590 Set mpegts flags. Accepts the following options:
1592 @item resend_headers
1593 Reemit PAT/PMT before writing the next packet.
1595 Use LATM packetization for AAC.
1596 @item pat_pmt_at_frames
1597 Reemit PAT and PMT at each video frame.
1599 Conform to System B (DVB) instead of System A (ATSC).
1600 @item initial_discontinuity
1601 Mark the initial packet of each stream as discontinuity.
1604 @item resend_headers @var{integer}
1605 Reemit PAT/PMT before writing the next packet. This option is deprecated:
1606 use @option{mpegts_flags} instead.
1608 @item mpegts_copyts @var{boolean}
1609 Preserve original timestamps, if value is set to @code{1}. Default value
1610 is @code{-1}, which results in shifting timestamps so that they start from 0.
1612 @item omit_video_pes_length @var{boolean}
1613 Omit the PES packet length for video packets. Default is @code{1} (true).
1615 @item pcr_period @var{integer}
1616 Override the default PCR retransmission time in milliseconds. Ignored if
1617 variable muxrate is selected. Default is @code{20}.
1619 @item pat_period @var{double}
1620 Maximum time in seconds between PAT/PMT tables.
1622 @item sdt_period @var{double}
1623 Maximum time in seconds between SDT tables.
1625 @item tables_version @var{integer}
1626 Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
1627 This option allows updating stream structure so that standard consumer may
1628 detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
1629 usage) or restart @command{ffmpeg} instance, cyclically changing
1630 @option{tables_version} value:
1633 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1634 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1636 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1637 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1638 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1646 ffmpeg -i file.mpg -c copy \
1647 -mpegts_original_network_id 0x1122 \
1648 -mpegts_transport_stream_id 0x3344 \
1649 -mpegts_service_id 0x5566 \
1650 -mpegts_pmt_start_pid 0x1500 \
1651 -mpegts_start_pid 0x150 \
1652 -metadata service_provider="Some provider" \
1653 -metadata service_name="Some Channel" \
1657 @section mxf, mxf_d10, mxf_opatom
1663 The muxer options are:
1666 @item store_user_comments @var{bool}
1667 Set if user comments should be stored if available or never.
1668 IRT D-10 does not allow user comments. The default is thus to write them for
1669 mxf and mxf_opatom but not for mxf_d10
1676 This muxer does not generate any output file, it is mainly useful for
1677 testing or benchmarking purposes.
1679 For example to benchmark decoding with @command{ffmpeg} you can use the
1682 ffmpeg -benchmark -i INPUT -f null out.null
1685 Note that the above command does not read or write the @file{out.null}
1686 file, but specifying the output file is required by the @command{ffmpeg}
1689 Alternatively you can write the command as:
1691 ffmpeg -benchmark -i INPUT -f null -
1697 @item -syncpoints @var{flags}
1698 Change the syncpoint usage in nut:
1700 @item @var{default} use the normal low-overhead seeking aids.
1701 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1702 Use of this option is not recommended, as the resulting files are very damage
1703 sensitive and seeking is not possible. Also in general the overhead from
1704 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1705 all growing data tables, allowing to mux endless streams with limited memory
1706 and without these disadvantages.
1707 @item @var{timestamped} extend the syncpoint with a wallclock field.
1709 The @var{none} and @var{timestamped} flags are experimental.
1710 @item -write_index @var{bool}
1711 Write index at the end, the default is to write an index.
1715 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1720 Ogg container muxer.
1723 @item -page_duration @var{duration}
1724 Preferred page duration, in microseconds. The muxer will attempt to create
1725 pages that are approximately @var{duration} microseconds long. This allows the
1726 user to compromise between seek granularity and container overhead. The default
1727 is 1 second. A value of 0 will fill all segments, making pages as large as
1728 possible. A value of 1 will effectively use 1 packet-per-page in most
1729 situations, giving a small seek granularity at the cost of additional container
1731 @item -serial_offset @var{value}
1732 Serial value from which to set the streams serial number.
1733 Setting it to different and sufficiently large values ensures that the produced
1734 ogg files can be safely chained.
1739 @section segment, stream_segment, ssegment
1741 Basic stream segmenter.
1743 This muxer outputs streams to a number of separate files of nearly
1744 fixed duration. Output filename pattern can be set in a fashion
1745 similar to @ref{image2}, or by using a @code{strftime} template if
1746 the @option{strftime} option is enabled.
1748 @code{stream_segment} is a variant of the muxer used to write to
1749 streaming output formats, i.e. which do not require global headers,
1750 and is recommended for outputting e.g. to MPEG transport stream segments.
1751 @code{ssegment} is a shorter alias for @code{stream_segment}.
1753 Every segment starts with a keyframe of the selected reference stream,
1754 which is set through the @option{reference_stream} option.
1756 Note that if you want accurate splitting for a video file, you need to
1757 make the input key frames correspond to the exact splitting times
1758 expected by the segmenter, or the segment muxer will start the new
1759 segment with the key frame found next after the specified start
1762 The segment muxer works best with a single constant frame rate video.
1764 Optionally it can generate a list of the created segments, by setting
1765 the option @var{segment_list}. The list type is specified by the
1766 @var{segment_list_type} option. The entry filenames in the segment
1767 list are set by default to the basename of the corresponding segment
1770 See also the @ref{hls} muxer, which provides a more specific
1771 implementation for HLS segmentation.
1775 The segment muxer supports the following options:
1778 @item increment_tc @var{1|0}
1779 if set to @code{1}, increment timecode between each segment
1780 If this is selected, the input need to have
1781 a timecode in the first video stream. Default value is
1784 @item reference_stream @var{specifier}
1785 Set the reference stream, as specified by the string @var{specifier}.
1786 If @var{specifier} is set to @code{auto}, the reference is chosen
1787 automatically. Otherwise it must be a stream specifier (see the ``Stream
1788 specifiers'' chapter in the ffmpeg manual) which specifies the
1789 reference stream. The default value is @code{auto}.
1791 @item segment_format @var{format}
1792 Override the inner container format, by default it is guessed by the filename
1795 @item segment_format_options @var{options_list}
1796 Set output format options using a :-separated list of key=value
1797 parameters. Values containing the @code{:} special character must be
1800 @item segment_list @var{name}
1801 Generate also a listfile named @var{name}. If not specified no
1802 listfile is generated.
1804 @item segment_list_flags @var{flags}
1805 Set flags affecting the segment list generation.
1807 It currently supports the following flags:
1810 Allow caching (only affects M3U8 list files).
1813 Allow live-friendly file generation.
1816 @item segment_list_size @var{size}
1817 Update the list file so that it contains at most @var{size}
1818 segments. If 0 the list file will contain all the segments. Default
1821 @item segment_list_entry_prefix @var{prefix}
1822 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1823 By default no prefix is applied.
1825 @item segment_list_type @var{type}
1826 Select the listing format.
1828 The following values are recognized:
1831 Generate a flat list for the created segments, one segment per line.
1834 Generate a list for the created segments, one segment per line,
1835 each line matching the format (comma-separated values):
1837 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1840 @var{segment_filename} is the name of the output file generated by the
1841 muxer according to the provided pattern. CSV escaping (according to
1842 RFC4180) is applied if required.
1844 @var{segment_start_time} and @var{segment_end_time} specify
1845 the segment start and end time expressed in seconds.
1847 A list file with the suffix @code{".csv"} or @code{".ext"} will
1848 auto-select this format.
1850 @samp{ext} is deprecated in favor or @samp{csv}.
1853 Generate an ffconcat file for the created segments. The resulting file
1854 can be read using the FFmpeg @ref{concat} demuxer.
1856 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1857 auto-select this format.
1860 Generate an extended M3U8 file, version 3, compliant with
1861 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1863 A list file with the suffix @code{".m3u8"} will auto-select this format.
1866 If not specified the type is guessed from the list file name suffix.
1868 @item segment_time @var{time}
1869 Set segment duration to @var{time}, the value must be a duration
1870 specification. Default value is "2". See also the
1871 @option{segment_times} option.
1873 Note that splitting may not be accurate, unless you force the
1874 reference stream key-frames at the given time. See the introductory
1875 notice and the examples below.
1877 @item segment_atclocktime @var{1|0}
1878 If set to "1" split at regular clock time intervals starting from 00:00
1879 o'clock. The @var{time} value specified in @option{segment_time} is
1880 used for setting the length of the splitting interval.
1882 For example with @option{segment_time} set to "900" this makes it possible
1883 to create files at 12:00 o'clock, 12:15, 12:30, etc.
1885 Default value is "0".
1887 @item segment_clocktime_offset @var{duration}
1888 Delay the segment splitting times with the specified duration when using
1889 @option{segment_atclocktime}.
1891 For example with @option{segment_time} set to "900" and
1892 @option{segment_clocktime_offset} set to "300" this makes it possible to
1893 create files at 12:05, 12:20, 12:35, etc.
1895 Default value is "0".
1897 @item segment_clocktime_wrap_duration @var{duration}
1898 Force the segmenter to only start a new segment if a packet reaches the muxer
1899 within the specified duration after the segmenting clock time. This way you
1900 can make the segmenter more resilient to backward local time jumps, such as
1901 leap seconds or transition to standard time from daylight savings time.
1903 Default is the maximum possible duration which means starting a new segment
1904 regardless of the elapsed time since the last clock time.
1906 @item segment_time_delta @var{delta}
1907 Specify the accuracy time when selecting the start time for a
1908 segment, expressed as a duration specification. Default value is "0".
1910 When delta is specified a key-frame will start a new segment if its
1911 PTS satisfies the relation:
1913 PTS >= start_time - time_delta
1916 This option is useful when splitting video content, which is always
1917 split at GOP boundaries, in case a key frame is found just before the
1918 specified split time.
1920 In particular may be used in combination with the @file{ffmpeg} option
1921 @var{force_key_frames}. The key frame times specified by
1922 @var{force_key_frames} may not be set accurately because of rounding
1923 issues, with the consequence that a key frame time may result set just
1924 before the specified time. For constant frame rate videos a value of
1925 1/(2*@var{frame_rate}) should address the worst case mismatch between
1926 the specified time and the time set by @var{force_key_frames}.
1928 @item segment_times @var{times}
1929 Specify a list of split points. @var{times} contains a list of comma
1930 separated duration specifications, in increasing order. See also
1931 the @option{segment_time} option.
1933 @item segment_frames @var{frames}
1934 Specify a list of split video frame numbers. @var{frames} contains a
1935 list of comma separated integer numbers, in increasing order.
1937 This option specifies to start a new segment whenever a reference
1938 stream key frame is found and the sequential number (starting from 0)
1939 of the frame is greater or equal to the next value in the list.
1941 @item segment_wrap @var{limit}
1942 Wrap around segment index once it reaches @var{limit}.
1944 @item segment_start_number @var{number}
1945 Set the sequence number of the first segment. Defaults to @code{0}.
1947 @item strftime @var{1|0}
1948 Use the @code{strftime} function to define the name of the new
1949 segments to write. If this is selected, the output segment name must
1950 contain a @code{strftime} function template. Default value is
1953 @item break_non_keyframes @var{1|0}
1954 If enabled, allow segments to start on frames other than keyframes. This
1955 improves behavior on some players when the time between keyframes is
1956 inconsistent, but may make things worse on others, and can cause some oddities
1957 during seeking. Defaults to @code{0}.
1959 @item reset_timestamps @var{1|0}
1960 Reset timestamps at the beginning of each segment, so that each segment
1961 will start with near-zero timestamps. It is meant to ease the playback
1962 of the generated segments. May not work with some combinations of
1963 muxers/codecs. It is set to @code{0} by default.
1965 @item initial_offset @var{offset}
1966 Specify timestamp offset to apply to the output packet timestamps. The
1967 argument must be a time duration specification, and defaults to 0.
1969 @item write_empty_segments @var{1|0}
1970 If enabled, write an empty segment if there are no packets during the period a
1971 segment would usually span. Otherwise, the segment will be filled with the next
1972 packet written. Defaults to @code{0}.
1975 Make sure to require a closed GOP when encoding and to set the GOP
1976 size to fit your segment time constraint.
1978 @subsection Examples
1982 Remux the content of file @file{in.mkv} to a list of segments
1983 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
1984 generated segments to @file{out.list}:
1986 ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
1990 Segment input and set output format options for the output segments:
1992 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
1996 Segment the input file according to the split points specified by the
1997 @var{segment_times} option:
1999 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
2003 Use the @command{ffmpeg} @option{force_key_frames}
2004 option to force key frames in the input at the specified location, together
2005 with the segment option @option{segment_time_delta} to account for
2006 possible roundings operated when setting key frame times.
2008 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
2009 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
2011 In order to force key frames on the input file, transcoding is
2015 Segment the input file by splitting the input file according to the
2016 frame numbers sequence specified with the @option{segment_frames} option:
2018 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
2022 Convert the @file{in.mkv} to TS segments using the @code{libx264}
2023 and @code{aac} encoders:
2025 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
2029 Segment the input file, and create an M3U8 live playlist (can be used
2030 as live HLS source):
2032 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
2033 -segment_list_flags +live -segment_time 10 out%03d.mkv
2037 @section smoothstreaming
2039 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
2043 Specify the number of fragments kept in the manifest. Default 0 (keep all).
2045 @item extra_window_size
2046 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
2048 @item lookahead_count
2049 Specify the number of lookahead fragments. Default 2.
2051 @item min_frag_duration
2052 Specify the minimum fragment duration (in microseconds). Default 5000000.
2054 @item remove_at_exit
2055 Specify whether to remove all fragments when finished. Default 0 (do not remove).
2062 The fifo pseudo-muxer allows the separation of encoding and muxing by using
2063 first-in-first-out queue and running the actual muxer in a separate thread. This
2064 is especially useful in combination with the @ref{tee} muxer and can be used to
2065 send data to several destinations with different reliability/writing speed/latency.
2067 API users should be aware that callback functions (interrupt_callback,
2068 io_open and io_close) used within its AVFormatContext must be thread-safe.
2070 The behavior of the fifo muxer if the queue fills up or if the output fails is
2076 output can be transparently restarted with configurable delay between retries
2077 based on real time or time of the processed stream.
2080 encoding can be blocked during temporary failure, or continue transparently
2081 dropping packets in case fifo queue fills up.
2088 Specify the format name. Useful if it cannot be guessed from the
2092 Specify size of the queue (number of packets). Default value is 60.
2095 Specify format options for the underlying muxer. Muxer options can be specified
2096 as a list of @var{key}=@var{value} pairs separated by ':'.
2098 @item drop_pkts_on_overflow @var{bool}
2099 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
2100 rather than blocking the encoder. This makes it possible to continue streaming without
2101 delaying the input, at the cost of omitting part of the stream. By default
2102 this option is set to 0 (false), so in such cases the encoder will be blocked
2103 until the muxer processes some of the packets and none of them is lost.
2105 @item attempt_recovery @var{bool}
2106 If failure occurs, attempt to recover the output. This is especially useful
2107 when used with network output, since it makes it possible to restart streaming transparently.
2108 By default this option is set to 0 (false).
2110 @item max_recovery_attempts
2111 Sets maximum number of successive unsuccessful recovery attempts after which
2112 the output fails permanently. By default this option is set to 0 (unlimited).
2114 @item recovery_wait_time @var{duration}
2115 Waiting time before the next recovery attempt after previous unsuccessful
2116 recovery attempt. Default value is 5 seconds.
2118 @item recovery_wait_streamtime @var{bool}
2119 If set to 0 (false), the real time is used when waiting for the recovery
2120 attempt (i.e. the recovery will be attempted after at least
2121 recovery_wait_time seconds).
2122 If set to 1 (true), the time of the processed stream is taken into account
2123 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
2124 seconds of the stream is omitted).
2125 By default, this option is set to 0 (false).
2127 @item recover_any_error @var{bool}
2128 If set to 1 (true), recovery will be attempted regardless of type of the error
2129 causing the failure. By default this option is set to 0 (false) and in case of
2130 certain (usually permanent) errors the recovery is not attempted even when
2131 @var{attempt_recovery} is set to 1.
2133 @item restart_with_keyframe @var{bool}
2134 Specify whether to wait for the keyframe after recovering from
2135 queue overflow or failure. This option is set to 0 (false) by default.
2139 @subsection Examples
2144 Stream something to rtmp server, continue processing the stream at real-time
2145 rate even in case of temporary failure (network outage) and attempt to recover
2146 streaming every second indefinitely.
2148 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
2149 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
2157 The tee muxer can be used to write the same data to several outputs, such as files or streams.
2158 It can be used, for example, to stream a video over a network and save it to disk at the same time.
2160 It is different from specifying several outputs to the @command{ffmpeg}
2161 command-line tool. With the tee muxer, the audio and video data will be encoded only once.
2162 With conventional multiple outputs, multiple encoding operations in parallel are initiated,
2163 which can be a very expensive process. The tee muxer is not useful when using the libavformat API
2164 directly because it is then possible to feed the same packets to several muxers directly.
2166 Since the tee muxer does not represent any particular output format, ffmpeg cannot auto-select
2167 output streams. So all streams intended for output must be specified using @code{-map}. See
2170 Some encoders may need different options depending on the output format;
2171 the auto-detection of this can not work with the tee muxer, so they need to be explicitly specified.
2172 The main example is the @option{global_header} flag.
2174 The slave outputs are specified in the file name given to the muxer,
2175 separated by '|'. If any of the slave name contains the '|' separator,
2176 leading or trailing spaces or any special character, those must be
2177 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
2178 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
2184 @item use_fifo @var{bool}
2185 If set to 1, slave outputs will be processed in separate threads using the @ref{fifo}
2186 muxer. This allows to compensate for different speed/latency/reliability of
2187 outputs and setup transparent recovery. By default this feature is turned off.
2190 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
2194 Muxer options can be specified for each slave by prepending them as a list of
2195 @var{key}=@var{value} pairs separated by ':', between square brackets. If
2196 the options values contain a special character or the ':' separator, they
2197 must be escaped; note that this is a second level escaping.
2199 The following special options are also recognized:
2202 Specify the format name. Required if it cannot be guessed from the
2205 @item bsfs[/@var{spec}]
2206 Specify a list of bitstream filters to apply to the specified
2209 It is possible to specify to which streams a given bitstream filter
2210 applies, by appending a stream specifier to the option separated by
2211 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
2212 stream specifiers}).
2214 If the stream specifier is not specified, the bitstream filters will be
2215 applied to all streams in the output. This will cause that output operation
2216 to fail if the output contains streams to which the bitstream filter cannot
2217 be applied e.g. @code{h264_mp4toannexb} being applied to an output containing an audio stream.
2219 Options for a bitstream filter must be specified in the form of @code{opt=value}.
2221 Several bitstream filters can be specified, separated by ",".
2223 @item use_fifo @var{bool}
2224 This allows to override tee muxer use_fifo option for individual slave muxer.
2227 This allows to override tee muxer fifo_options for individual slave muxer.
2231 Select the streams that should be mapped to the slave output,
2232 specified by a stream specifier. If not specified, this defaults to
2233 all the mapped streams. This will cause that output operation to fail
2234 if the output format does not accept all mapped streams.
2236 You may use multiple stream specifiers separated by commas (@code{,}) e.g.: @code{a:0,v}
2239 Specify behaviour on output failure. This can be set to either @code{abort} (which is
2240 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
2241 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
2242 will continue without being affected.
2245 @subsection Examples
2249 Encode something and both archive it in a WebM file and stream it
2250 as MPEG-TS over UDP:
2252 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2253 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2257 As above, but continue streaming even if output to local file fails
2258 (for example local drive fills up):
2260 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2261 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2265 Use @command{ffmpeg} to encode the input, and send the output
2266 to three different destinations. The @code{dump_extra} bitstream
2267 filter is used to add extradata information to all the output video
2268 keyframes packets, as requested by the MPEG-TS format. The select
2269 option is applied to @file{out.aac} in order to make it contain only
2272 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2273 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
2277 As above, but select only stream @code{a:1} for the audio output. Note
2278 that a second level escaping must be performed, as ":" is a special
2279 character used to separate options.
2281 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2282 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
2286 @section webm_dash_manifest
2288 WebM DASH Manifest muxer.
2290 This muxer implements the WebM DASH Manifest specification to generate the DASH
2291 manifest XML. It also supports manifest generation for DASH live streams.
2293 For more information see:
2297 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
2299 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
2304 This muxer supports the following options:
2307 @item adaptation_sets
2308 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
2309 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
2310 audio and video streams. Any number of adaptation sets can be added using this option.
2313 Set this to 1 to create a live stream DASH Manifest. Default: 0.
2315 @item chunk_start_index
2316 Start index of the first chunk. This will go in the @samp{startNumber} attribute
2317 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
2319 @item chunk_duration_ms
2320 Duration of each chunk in milliseconds. This will go in the @samp{duration}
2321 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
2323 @item utc_timing_url
2324 URL of the page that will return the UTC timestamp in ISO format. This will go
2325 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
2328 @item time_shift_buffer_depth
2329 Smallest time (in seconds) shifting buffer for which any Representation is
2330 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
2331 attribute of the @samp{MPD} element. Default: 60.
2333 @item minimum_update_period
2334 Minimum update period (in seconds) of the manifest. This will go in the
2335 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
2341 ffmpeg -f webm_dash_manifest -i video1.webm \
2342 -f webm_dash_manifest -i video2.webm \
2343 -f webm_dash_manifest -i audio1.webm \
2344 -f webm_dash_manifest -i audio2.webm \
2345 -map 0 -map 1 -map 2 -map 3 \
2347 -f webm_dash_manifest \
2348 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
2354 WebM Live Chunk Muxer.
2356 This muxer writes out WebM headers and chunks as separate files which can be
2357 consumed by clients that support WebM Live streams via DASH.
2361 This muxer supports the following options:
2364 @item chunk_start_index
2365 Index of the first chunk (defaults to 0).
2368 Filename of the header where the initialization data will be written.
2370 @item audio_chunk_duration
2371 Duration of each audio chunk in milliseconds (defaults to 5000).
2376 ffmpeg -f v4l2 -i /dev/video0 \
2380 -s 640x360 -keyint_min 30 -g 30 \
2382 -header webm_live_video_360.hdr \
2383 -chunk_start_index 1 \
2384 webm_live_video_360_%d.chk \
2389 -header webm_live_audio_128.hdr \
2390 -chunk_start_index 1 \
2391 -audio_chunk_duration 1000 \
2392 webm_live_audio_128_%d.chk