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 "$Time$".
221 ffmpeg -re -i <input> -map 0 -map 0 -c:a libfdk_aac -c:v libx264
222 -b:v:0 800k -b:v:1 300k -s:v:1 320x170 -profile:v:1 baseline
223 -profile:v:0 main -bf 1 -keyint_min 120 -g 120 -sc_threshold 0
224 -b_strategy 0 -ar:a:1 22050 -use_timeline 1 -use_template 1
225 -window_size 5 -adaptation_sets "id=0,streams=v id=1,streams=a"
226 -f dash /path/to/out.mpd
230 @item -min_seg_duration @var{microseconds}
231 This is a deprecated option to set the segment length in microseconds, use @var{seg_duration} instead.
232 @item -seg_duration @var{duration}
233 Set the segment length in seconds (fractional value can be set). The value is
234 treated as average segment duration when @var{use_template} is enabled and
235 @var{use_timeline} is disabled and as minimum segment duration for all the other
237 @item -window_size @var{size}
238 Set the maximum number of segments kept in the manifest.
239 @item -extra_window_size @var{size}
240 Set the maximum number of segments kept outside of the manifest before removing from disk.
241 @item -remove_at_exit @var{remove}
242 Enable (1) or disable (0) removal of all segments when finished.
243 @item -use_template @var{template}
244 Enable (1) or disable (0) use of SegmentTemplate instead of SegmentList.
245 @item -use_timeline @var{timeline}
246 Enable (1) or disable (0) use of SegmentTimeline in SegmentTemplate.
247 @item -single_file @var{single_file}
248 Enable (1) or disable (0) storing all segments in one file, accessed using byte ranges.
249 @item -single_file_name @var{file_name}
250 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.
251 @item -init_seg_name @var{init_name}
252 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.
253 @item -media_seg_name @var{segment_name}
254 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.
255 @item -utc_timing_url @var{utc_url}
256 URL of the page that will return the UTC timestamp in ISO format. Example: "https://time.akamai.com/?iso"
257 @item method @var{method}
258 Use the given HTTP method to create output files. Generally set to PUT or POST.
259 @item -http_user_agent @var{user_agent}
260 Override User-Agent field in HTTP header. Applicable only for HTTP output.
261 @item -http_persistent @var{http_persistent}
262 Use persistent HTTP connections. Applicable only for HTTP output.
263 @item -hls_playlist @var{hls_playlist}
264 Generate HLS playlist files as well. The master playlist is generated with the filename master.m3u8.
265 One media playlist file is generated for each stream with filenames media_0.m3u8, media_1.m3u8, etc.
266 @item -streaming @var{streaming}
267 Enable (1) or disable (0) chunk streaming mode of output. In chunk streaming
268 mode, each frame will be a moof fragment which forms a chunk.
269 @item -adaptation_sets @var{adaptation_sets}
270 Assign streams to AdaptationSets. Syntax is "id=x,streams=a,b,c id=y,streams=d,e" with x and y being the IDs
271 of the adaptation sets and a,b,c,d and e are the indices of the mapped streams.
273 To map all video (or audio) streams to an AdaptationSet, "v" (or "a") can be used as stream identifier instead of IDs.
275 When no assignment is defined, this defaults to an AdaptationSet for each stream.
276 @item -timeout @var{timeout}
277 Set timeout for socket I/O operations. Applicable only for HTTP output.
278 @item -index_correction @var{index_correction}
279 Enable (1) or Disable (0) segment index correction logic. Applicable only when
280 @var{use_template} is enabled and @var{use_timeline} is disabled.
282 When enabled, the logic monitors the flow of segment indexes. If a streams's
283 segment index value is not at the expected real time position, then the logic
284 corrects that index value.
286 Typically this logic is needed in live streaming use cases. The network bandwidth
287 fluctuations are common during long run streaming. Each fluctuation can cause
288 the segment indexes fall behind the expected real time position.
289 @item -format_options @var{options_list}
290 Set container format (mp4/webm) options using a @code{:} separated list of
291 key=value parameters. Values containing @code{:} special characters must be
294 @item -dash_segment_type @var{dash_segment_type}
297 If this flag is set, the dash segment files format will be selected based on the stream codec. This is the default mode.
300 If this flag is set, the dash segment files will be in in ISOBMFF format.
303 If this flag is set, the dash segment files will be in in WebM format.
305 @item -ignore_io_errors @var{ignore_io_errors}
306 Ignore IO errors during open and write. Useful for long-duration runs with network output.
313 Per-packet CRC (Cyclic Redundancy Check) testing format.
315 This muxer computes and prints the Adler-32 CRC for each audio
316 and video packet. By default audio frames are converted to signed
317 16-bit raw audio and video frames to raw video before computing the
320 The output of the muxer consists of a line for each audio and video
323 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
326 @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
331 For example to compute the CRC of the audio and video frames in
332 @file{INPUT}, converted to raw audio and video packets, and store it
333 in the file @file{out.crc}:
335 ffmpeg -i INPUT -f framecrc out.crc
338 To print the information to stdout, use the command:
340 ffmpeg -i INPUT -f framecrc -
343 With @command{ffmpeg}, you can select the output format to which the
344 audio and video frames are encoded before computing the CRC for each
345 packet by specifying the audio and video codec. For example, to
346 compute the CRC of each decoded input audio frame converted to PCM
347 unsigned 8-bit and of each decoded input video frame converted to
348 MPEG-2 video, use the command:
350 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
353 See also the @ref{crc} muxer.
358 Per-packet hash testing format.
360 This muxer computes and prints a cryptographic hash for each audio
361 and video packet. This can be used for packet-by-packet equality
362 checks without having to individually do a binary comparison on each.
364 By default audio frames are converted to signed 16-bit raw audio and
365 video frames to raw video before computing the hash, but the output
366 of explicit conversions to other codecs can also be used. It uses the
367 SHA-256 cryptographic hash function by default, but supports several
370 The output of the muxer consists of a line for each audio and video
373 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
376 @var{hash} is a hexadecimal number representing the computed hash
380 @item hash @var{algorithm}
381 Use the cryptographic hash function specified by the string @var{algorithm}.
382 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
383 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
384 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
385 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
391 To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
392 converted to raw audio and video packets, and store it in the file
395 ffmpeg -i INPUT -f framehash out.sha256
398 To print the information to stdout, using the MD5 hash function, use
401 ffmpeg -i INPUT -f framehash -hash md5 -
404 See also the @ref{hash} muxer.
409 Per-packet MD5 testing format.
411 This is a variant of the @ref{framehash} muxer. Unlike that muxer,
412 it defaults to using the MD5 hash function.
416 To compute the MD5 hash of the audio and video frames in @file{INPUT},
417 converted to raw audio and video packets, and store it in the file
420 ffmpeg -i INPUT -f framemd5 out.md5
423 To print the information to stdout, use the command:
425 ffmpeg -i INPUT -f framemd5 -
428 See also the @ref{framehash} and @ref{md5} muxers.
435 It accepts the following options:
439 Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
440 for looping indefinitely (default).
443 Force the delay (expressed in centiseconds) after the last frame. Each frame
444 ends with a delay until the next frame. The default is @code{-1}, which is a
445 special value to tell the muxer to re-use the previous delay. In case of a
446 loop, you might want to customize this value to mark a pause for instance.
449 For example, to encode a gif looping 10 times, with a 5 seconds delay between
452 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
455 Note 1: if you wish to extract the frames into separate GIF files, you need to
456 force the @ref{image2} muxer:
458 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
461 Note 2: the GIF format has a very large time base: the delay between two frames
462 can therefore not be smaller than one centi second.
469 This muxer computes and prints a cryptographic hash of all the input
470 audio and video frames. This can be used for equality checks without
471 having to do a complete binary comparison.
473 By default audio frames are converted to signed 16-bit raw audio and
474 video frames to raw video before computing the hash, but the output
475 of explicit conversions to other codecs can also be used. Timestamps
476 are ignored. It uses the SHA-256 cryptographic hash function by default,
477 but supports several other algorithms.
479 The output of the muxer consists of a single line of the form:
480 @var{algo}=@var{hash}, where @var{algo} is a short string representing
481 the hash function used, and @var{hash} is a hexadecimal number
482 representing the computed hash.
485 @item hash @var{algorithm}
486 Use the cryptographic hash function specified by the string @var{algorithm}.
487 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
488 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
489 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
490 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
496 To compute the SHA-256 hash of the input converted to raw audio and
497 video, and store it in the file @file{out.sha256}:
499 ffmpeg -i INPUT -f hash out.sha256
502 To print an MD5 hash to stdout use the command:
504 ffmpeg -i INPUT -f hash -hash md5 -
507 See also the @ref{framehash} muxer.
512 Apple HTTP Live Streaming muxer that segments MPEG-TS according to
513 the HTTP Live Streaming (HLS) specification.
515 It creates a playlist file, and one or more segment files. The output filename
516 specifies the playlist filename.
518 By default, the muxer creates a file for each segment produced. These files
519 have the same name as the playlist, followed by a sequential number and a
522 Make sure to require a closed GOP when encoding and to set the GOP
523 size to fit your segment time constraint.
525 For example, to convert an input file with @command{ffmpeg}:
527 ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
529 This example will produce the playlist, @file{out.m3u8}, and segment files:
530 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
532 See also the @ref{segment} muxer, which provides a more generic and
533 flexible implementation of a segmenter, and can be used to perform HLS
538 This muxer supports the following options:
541 @item hls_init_time @var{seconds}
542 Set the initial target segment length in seconds. Default value is @var{0}.
543 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
544 After the initial playlist is filled @command{ffmpeg} will cut segments
545 at duration equal to @code{hls_time}
547 @item hls_time @var{seconds}
548 Set the target segment length in seconds. Default value is 2.
549 Segment will be cut on the next key frame after this time has passed.
551 @item hls_list_size @var{size}
552 Set the maximum number of playlist entries. If set to 0 the list file
553 will contain all the segments. Default value is 5.
555 @item hls_delete_threshold @var{size}
556 Set the number of unreferenced segments to keep on disk before @code{hls_flags delete_segments}
557 deletes them. Increase this to allow continue clients to download segments which
558 were recently referenced in the playlist. Default value is 1, meaning segments older than
559 @code{hls_list_size+1} will be deleted.
561 @item hls_ts_options @var{options_list}
562 Set output format options using a :-separated list of key=value
563 parameters. Values containing @code{:} special characters must be
566 @item hls_wrap @var{wrap}
567 This is a deprecated option, you can use @code{hls_list_size}
568 and @code{hls_flags delete_segments} instead it
570 This option is useful to avoid to fill the disk with many segment
571 files, and limits the maximum number of segment files written to disk
575 @item hls_start_number_source
576 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
577 Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
578 segment and subtitle filenames. In any case, if @code{hls_flags append_list}
579 is set and read playlist sequence number is greater than the specified start sequence number,
580 then that value will be used as start value.
582 It accepts the following values:
586 @item generic (default)
587 Set the starting sequence numbers according to @var{start_number} option value.
590 The start number will be the seconds since epoch (1970-01-01 00:00:00)
593 The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
597 @item start_number @var{number}
598 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
599 when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
600 Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
603 @item hls_allow_cache @var{allowcache}
604 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
606 @item hls_base_url @var{baseurl}
607 Append @var{baseurl} to every entry in the playlist.
608 Useful to generate playlists with absolute paths.
610 Note that the playlist sequence number must be unique for each segment
611 and it is not to be confused with the segment filename sequence number
612 which can be cyclic, for example if the @option{wrap} option is
615 @item hls_segment_filename @var{filename}
616 Set the segment filename. Unless @code{hls_flags single_file} is set,
617 @var{filename} is used as a string format with the segment number:
619 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
621 This example will produce the playlist, @file{out.m3u8}, and segment files:
622 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
624 @var{filename} may contain full path or relative path specification,
625 but only the file name part without any path info will be contained in the m3u8 segment list.
626 Should a relative path be specified, the path of the created segment
627 files will be relative to the current working directory.
628 When strftime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
630 When @code{var_stream_map} is set with two or more variant streams, the
631 @var{filename} pattern must contain the string "%v", this string specifies
632 the position of variant stream index in the generated segment file names.
634 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
635 -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" \
636 -hls_segment_filename 'file_%v_%03d.ts' out_%v.m3u8
638 This example will produce the playlists segment file sets:
639 @file{file_0_000.ts}, @file{file_0_001.ts}, @file{file_0_002.ts}, etc. and
640 @file{file_1_000.ts}, @file{file_1_001.ts}, @file{file_1_002.ts}, etc.
642 The string "%v" may be present in the filename or in the last directory name
643 containing the file. If the string is present in the directory name, then
644 sub-directories are created after expanding the directory name pattern. This
645 enables creation of segments corresponding to different variant streams in
648 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
649 -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" \
650 -hls_segment_filename 'vs%v/file_%03d.ts' vs%v/out.m3u8
652 This example will produce the playlists segment file sets:
653 @file{vs0/file_000.ts}, @file{vs0/file_001.ts}, @file{vs0/file_002.ts}, etc. and
654 @file{vs1/file_000.ts}, @file{vs1/file_001.ts}, @file{vs1/file_002.ts}, etc.
657 Same as strftime option, will be deprecated.
660 Use strftime() on @var{filename} to expand the segment filename with localtime.
661 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
662 hls_flag and %%d will be the specifier.
664 ffmpeg -i in.nut -strftime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
666 This example will produce the playlist, @file{out.m3u8}, and segment files:
667 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
668 Note: On some systems/environments, the @code{%s} specifier is not available. See
669 @code{strftime()} documentation.
671 ffmpeg -i in.nut -strftime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
673 This example will produce the playlist, @file{out.m3u8}, and segment files:
674 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
676 @item use_localtime_mkdir
677 Same as strftime_mkdir option, will be deprecated .
680 Used together with -strftime_mkdir, it will create all subdirectories which
681 is expanded in @var{filename}.
683 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y%m%d/file-%Y%m%d-%s.ts' out.m3u8
685 This example will create a directory 201560215 (if it does not exist), and then
686 produce the playlist, @file{out.m3u8}, and segment files:
687 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
690 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y/%m/%d/file-%Y%m%d-%s.ts' out.m3u8
692 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
693 produce the playlist, @file{out.m3u8}, and segment files:
694 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
697 @item hls_key_info_file @var{key_info_file}
698 Use the information in @var{key_info_file} for segment encryption. The first
699 line of @var{key_info_file} specifies the key URI written to the playlist. The
700 key URL is used to access the encryption key during playback. The second line
701 specifies the path to the key file used to obtain the key during the encryption
702 process. The key file is read as a single packed array of 16 octets in binary
703 format. The optional third line specifies the initialization vector (IV) as a
704 hexadecimal string to be used instead of the segment sequence number (default)
705 for encryption. Changes to @var{key_info_file} will result in segment
706 encryption with the new key/IV and an entry in the playlist for the new key
707 URI/IV if @code{hls_flags periodic_rekey} is enabled.
709 Key info file format:
718 http://server/file.key
723 Example key file paths:
731 0123456789ABCDEF0123456789ABCDEF
734 Key info file example:
736 http://server/file.key
738 0123456789ABCDEF0123456789ABCDEF
741 Example shell script:
745 openssl rand 16 > file.key
746 echo $BASE_URL/file.key > file.keyinfo
747 echo file.key >> file.keyinfo
748 echo $(openssl rand -hex 16) >> file.keyinfo
749 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
750 -hls_key_info_file file.keyinfo out.m3u8
753 @item -hls_enc @var{enc}
754 Enable (1) or disable (0) the AES128 encryption.
755 When enabled every segment generated is encrypted and the encryption key
756 is saved as @var{playlist name}.key.
758 @item -hls_enc_key @var{key}
759 Hex-coded 16byte key to encrypt the segments, by default it
760 is randomly generated.
762 @item -hls_enc_key_url @var{keyurl}
763 If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
766 @item -hls_enc_iv @var{iv}
767 Hex-coded 16byte initialization vector for every segment instead
768 of the autogenerated ones.
770 @item hls_segment_type @var{flags}
775 Output segment files in MPEG-2 Transport Stream format. This is
776 compatible with all HLS versions.
779 Output segment files in fragmented MP4 format, similar to MPEG-DASH.
780 fmp4 files may be used in HLS version 7 and above.
784 @item hls_fmp4_init_filename @var{filename}
785 Set filename to the fragment files header file, default filename is @file{init.mp4}.
787 When @code{var_stream_map} is set with two or more variant streams, the
788 @var{filename} pattern must contain the string "%v", this string specifies
789 the position of variant stream index in the generated init file names.
790 The string "%v" may be present in the filename or in the last directory name
791 containing the file. If the string is present in the directory name, then
792 sub-directories are created after expanding the directory name pattern. This
793 enables creation of init files corresponding to different variant streams in
796 @item hls_flags @var{flags}
801 If this flag is set, the muxer will store all segments in a single MPEG-TS
802 file, and will use byte ranges in the playlist. HLS playlists generated with
803 this way will have the version number 4.
806 ffmpeg -i in.nut -hls_flags single_file out.m3u8
808 Will produce the playlist, @file{out.m3u8}, and a single segment file,
811 @item delete_segments
812 Segment files removed from the playlist are deleted after a period of time
813 equal to the duration of the segment plus the duration of the playlist.
816 Append new segments into the end of old segment list,
817 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
819 @item round_durations
820 Round the duration info in the playlist file segment info to integer
821 values, instead of using floating point.
824 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
825 first segment's information.
828 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
831 The file specified by @code{hls_key_info_file} will be checked periodically and
832 detect updates to the encryption info. Be sure to replace this file atomically,
833 including the file containing the AES encryption key.
835 @item independent_segments
836 Add the @code{#EXT-X-INDEPENDENT-SEGMENTS} to playlists that has video segments
837 and when all the segments of that playlist are guaranteed to start with a Key frame.
840 Allow segments to start on frames other than keyframes. This improves
841 behavior on some players when the time between keyframes is inconsistent,
842 but may make things worse on others, and can cause some oddities during
843 seeking. This flag should be used with the @code{hls_time} option.
845 @item program_date_time
846 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
848 @item second_level_segment_index
849 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
850 besides date/time values when strftime is on.
851 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
853 @item second_level_segment_size
854 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
855 expression besides date/time values when strftime is on.
856 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
858 @item second_level_segment_duration
859 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
860 expression besides date/time values when strftime is on.
861 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
864 ffmpeg -i sample.mpeg \
865 -f hls -hls_time 3 -hls_list_size 5 \
866 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
867 -strftime 1 -strftime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
869 This will produce segments like this:
870 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
873 Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
874 serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
875 before they have been added to the m3u8 playlist.
879 @item hls_playlist_type event
880 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
881 @option{hls_list_size} to 0; the playlist can only be appended to.
883 @item hls_playlist_type vod
884 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
885 @option{hls_list_size} to 0; the playlist must not change.
888 Use the given HTTP method to create the hls files.
890 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
892 This example will upload all the mpegts segment files to the HTTP
893 server using the HTTP PUT method, and update the m3u8 files every
894 @code{refresh} times using the same method.
895 Note that the HTTP server must support the given method for uploading
898 @item http_user_agent
899 Override User-Agent field in HTTP header. Applicable only for HTTP output.
902 Map string which specifies how to group the audio, video and subtitle streams
903 into different variant streams. The variant stream groups are separated
905 Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
906 the keys to specify audio, video and subtitle streams respectively.
907 Allowed values are 0 to 9 (limited just based on practical usage).
909 When there are two or more variant streams, the output filename pattern must
910 contain the string "%v", this string specifies the position of variant stream
911 index in the output media playlist filenames. The string "%v" may be present in
912 the filename or in the last directory name containing the file. If the string is
913 present in the directory name, then sub-directories are created after expanding
914 the directory name pattern. This enables creation of variant streams in
918 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
919 -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" \
920 http://example.com/live/out_%v.m3u8
922 This example creates two hls variant streams. The first variant stream will
923 contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
924 second variant stream will contain video stream of bitrate 256k and audio
925 stream of bitrate 32k. Here, two media playlist with file names out_0.m3u8 and
926 out_1.m3u8 will be created.
928 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
929 -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
930 http://example.com/live/out_%v.m3u8
932 This example creates three hls variant streams. The first variant stream will
933 be a video only stream with video bitrate 1000k, the second variant stream will
934 be an audio only stream with bitrate 64k and the third variant stream will be a
935 video only stream with bitrate 256k. Here, three media playlist with file names
936 out_0.m3u8, out_1.m3u8 and out_2.m3u8 will be created.
938 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
939 -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" \
940 http://example.com/live/vs_%v/out.m3u8
942 This example creates the variant streams in subdirectories. Here, the first
943 media playlist is created at @file{http://example.com/live/vs_0/out.m3u8} and
944 the second one at @file{http://example.com/live/vs_1/out.m3u8}.
946 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k \
947 -map 0:a -map 0:a -map 0:v -map 0:v -f hls \
948 -var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
949 -master_pl_name master.m3u8 \
950 http://example.com/live/out_%v.m3u8
952 This example creates two audio only and two video only variant streams. In
953 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
954 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
955 and they are mapped to the two video only variant streams with audio group names
956 'aud_low' and 'aud_high'.
958 By default, a single hls variant containing all the encoded streams is created.
961 Map string which specifies different closed captions groups and their
962 attributes. The closed captions stream groups are separated by space.
963 Expected string format is like this
964 "ccgroup:<group name>,instreamid:<INSTREAM-ID>,language:<language code> ....".
965 'ccgroup' and 'instreamid' are mandatory attributes. 'language' is an optional
967 The closed captions groups configured using this option are mapped to different
968 variant streams by providing the same 'ccgroup' name in the
969 @code{var_stream_map} string. If @code{var_stream_map} is not set, then the
970 first available ccgroup in @code{cc_stream_map} is mapped to the output variant
971 stream. The examples for these two use cases are given below.
974 ffmpeg -re -i in.ts -b:v 1000k -b:a 64k -a53cc 1 -f hls \
975 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en" \
976 -master_pl_name master.m3u8 \
977 http://example.com/live/out.m3u8
979 This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=CLOSED-CAPTIONS} in
980 the master playlist with group name 'cc', langauge 'en' (english) and
981 INSTREAM-ID 'CC1'. Also, it adds @code{CLOSED-CAPTIONS} attribute with group
982 name 'cc' for the output variant stream.
984 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
985 -a53cc:0 1 -a53cc:1 1\
986 -map 0:v -map 0:a -map 0:v -map 0:a -f hls \
987 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en ccgroup:cc,instreamid:CC2,language:sp" \
988 -var_stream_map "v:0,a:0,ccgroup:cc v:1,a:1,ccgroup:cc" \
989 -master_pl_name master.m3u8 \
990 http://example.com/live/out_%v.m3u8
992 This example adds two @code{#EXT-X-MEDIA} tags with @code{TYPE=CLOSED-CAPTIONS} in
993 the master playlist for the INSTREAM-IDs 'CC1' and 'CC2'. Also, it adds
994 @code{CLOSED-CAPTIONS} attribute with group name 'cc' for the two output variant
998 Create HLS master playlist with the given name.
1001 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
1003 This example creates HLS master playlist with name master.m3u8 and it is
1004 published at http://example.com/live/
1006 @item master_pl_publish_rate
1007 Publish master play list repeatedly every after specified number of segment intervals.
1010 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
1011 -hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
1014 This example creates HLS master playlist with name master.m3u8 and keep
1015 publishing it repeatedly every after 30 segments i.e. every after 60s.
1017 @item http_persistent
1018 Use persistent HTTP connections. Applicable only for HTTP output.
1021 Set timeout for socket I/O operations. Applicable only for HTTP output.
1030 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
1034 Size cannot exceed 256 pixels in any dimension
1037 Only BMP and PNG images can be stored
1040 If a BMP image is used, it must be one of the following pixel formats:
1042 BMP Bit Depth FFmpeg Pixel Format
1052 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
1055 If a PNG image is used, it must use the rgba pixel format
1063 The image file muxer writes video frames to image files.
1065 The output filenames are specified by a pattern, which can be used to
1066 produce sequentially numbered series of files.
1067 The pattern may contain the string "%d" or "%0@var{N}d", this string
1068 specifies the position of the characters representing a numbering in
1069 the filenames. If the form "%0@var{N}d" is used, the string
1070 representing the number in each filename is 0-padded to @var{N}
1071 digits. The literal character '%' can be specified in the pattern with
1074 If the pattern contains "%d" or "%0@var{N}d", the first filename of
1075 the file list specified will contain the number 1, all the following
1076 numbers will be sequential.
1078 The pattern may contain a suffix which is used to automatically
1079 determine the format of the image files to write.
1081 For example the pattern "img-%03d.bmp" will specify a sequence of
1082 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
1083 @file{img-010.bmp}, etc.
1084 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
1085 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
1088 @subsection Examples
1090 The following example shows how to use @command{ffmpeg} for creating a
1091 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
1092 taking one image every second from the input video:
1094 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
1097 Note that with @command{ffmpeg}, if the format is not specified with the
1098 @code{-f} option and the output filename specifies an image file
1099 format, the image2 muxer is automatically selected, so the previous
1100 command can be written as:
1102 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
1105 Note also that the pattern must not necessarily contain "%d" or
1106 "%0@var{N}d", for example to create a single image file
1107 @file{img.jpeg} from the start of the input video you can employ the command:
1109 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
1112 The @option{strftime} option allows you to expand the filename with
1113 date and time information. Check the documentation of
1114 the @code{strftime()} function for the syntax.
1116 For example to generate image files from the @code{strftime()}
1117 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
1120 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
1123 You can set the file name with current frame's PTS:
1125 ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
1132 If set to 1, expand the filename with pts from pkt->pts.
1136 Start the sequence from the specified number. Default value is 1.
1139 If set to 1, the filename will always be interpreted as just a
1140 filename, not a pattern, and the corresponding file will be continuously
1141 overwritten with new images. Default value is 0.
1144 If set to 1, expand the filename with date and time information from
1145 @code{strftime()}. Default value is 0.
1148 The image muxer supports the .Y.U.V image file format. This format is
1149 special in that that each image frame consists of three files, for
1150 each of the YUV420P components. To read or write this image file format,
1151 specify the name of the '.Y' file. The muxer will automatically open the
1152 '.U' and '.V' files as required.
1156 Matroska container muxer.
1158 This muxer implements the matroska and webm container specs.
1160 @subsection Metadata
1162 The recognized metadata settings in this muxer are:
1166 Set title name provided to a single track.
1169 Specify the language of the track in the Matroska languages form.
1171 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
1172 639-2/B) form (like "fre" for French), or a language code mixed with a
1173 country code for specialities in languages (like "fre-ca" for Canadian
1177 Set stereo 3D video layout of two views in a single video track.
1179 The following values are recognized:
1184 Both views are arranged side by side, Left-eye view is on the left
1186 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
1188 Both views are arranged in top-bottom orientation, Left-eye view is on top
1189 @item checkerboard_rl
1190 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
1191 @item checkerboard_lr
1192 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
1193 @item row_interleaved_rl
1194 Each view is constituted by a row based interleaving, Right-eye view is first row
1195 @item row_interleaved_lr
1196 Each view is constituted by a row based interleaving, Left-eye view is first row
1197 @item col_interleaved_rl
1198 Both views are arranged in a column based interleaving manner, Right-eye view is first column
1199 @item col_interleaved_lr
1200 Both views are arranged in a column based interleaving manner, Left-eye view is first column
1201 @item anaglyph_cyan_red
1202 All frames are in anaglyph format viewable through red-cyan filters
1204 Both views are arranged side by side, Right-eye view is on the left
1205 @item anaglyph_green_magenta
1206 All frames are in anaglyph format viewable through green-magenta filters
1208 Both eyes laced in one Block, Left-eye view is first
1210 Both eyes laced in one Block, Right-eye view is first
1214 For example a 3D WebM clip can be created using the following command line:
1216 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
1221 This muxer supports the following options:
1224 @item reserve_index_space
1225 By default, this muxer writes the index for seeking (called cues in Matroska
1226 terms) at the end of the file, because it cannot know in advance how much space
1227 to leave for the index at the beginning of the file. However for some use cases
1228 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
1229 index at the beginning of the file.
1231 If this option is set to a non-zero value, the muxer will reserve a given amount
1232 of space in the file header and then try to write the cues there when the muxing
1233 finishes. If the available space does not suffice, muxing will fail. A safe size
1234 for most use cases should be about 50kB per hour of video.
1236 Note that cues are only written if the output is seekable and this option will
1237 have no effect if it is not.
1245 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
1246 defaults to using the MD5 hash function.
1248 @subsection Examples
1250 To compute the MD5 hash of the input converted to raw
1251 audio and video, and store it in the file @file{out.md5}:
1253 ffmpeg -i INPUT -f md5 out.md5
1256 You can print the MD5 to stdout with the command:
1258 ffmpeg -i INPUT -f md5 -
1261 See also the @ref{hash} and @ref{framemd5} muxers.
1263 @section mov, mp4, ismv
1265 MOV/MP4/ISMV (Smooth Streaming) muxer.
1267 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
1268 file has all the metadata about all packets stored in one location
1269 (written at the end of the file, it can be moved to the start for
1270 better playback by adding @var{faststart} to the @var{movflags}, or
1271 using the @command{qt-faststart} tool). A fragmented
1272 file consists of a number of fragments, where packets and metadata
1273 about these packets are stored together. Writing a fragmented
1274 file has the advantage that the file is decodable even if the
1275 writing is interrupted (while a normal MOV/MP4 is undecodable if
1276 it is not properly finished), and it requires less memory when writing
1277 very long files (since writing normal MOV/MP4 files stores info about
1278 every single packet in memory until the file is closed). The downside
1279 is that it is less compatible with other applications.
1283 Fragmentation is enabled by setting one of the AVOptions that define
1284 how to cut the file into fragments:
1287 @item -moov_size @var{bytes}
1288 Reserves space for the moov atom at the beginning of the file instead of placing the
1289 moov atom at the end. If the space reserved is insufficient, muxing will fail.
1290 @item -movflags frag_keyframe
1291 Start a new fragment at each video keyframe.
1292 @item -frag_duration @var{duration}
1293 Create fragments that are @var{duration} microseconds long.
1294 @item -frag_size @var{size}
1295 Create fragments that contain up to @var{size} bytes of payload data.
1296 @item -movflags frag_custom
1297 Allow the caller to manually choose when to cut fragments, by
1298 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
1299 the packets written so far. (This is only useful with other
1300 applications integrating libavformat, not from @command{ffmpeg}.)
1301 @item -min_frag_duration @var{duration}
1302 Don't create fragments that are shorter than @var{duration} microseconds long.
1305 If more than one condition is specified, fragments are cut when
1306 one of the specified conditions is fulfilled. The exception to this is
1307 @code{-min_frag_duration}, which has to be fulfilled for any of the other
1308 conditions to apply.
1310 Additionally, the way the output file is written can be adjusted
1311 through a few other options:
1314 @item -movflags empty_moov
1315 Write an initial moov atom directly at the start of the file, without
1316 describing any samples in it. Generally, an mdat/moov pair is written
1317 at the start of the file, as a normal MOV/MP4 file, containing only
1318 a short portion of the file. With this option set, there is no initial
1319 mdat atom, and the moov atom only describes the tracks but has
1322 This option is implicitly set when writing ismv (Smooth Streaming) files.
1323 @item -movflags separate_moof
1324 Write a separate moof (movie fragment) atom for each track. Normally,
1325 packets for all tracks are written in a moof atom (which is slightly
1326 more efficient), but with this option set, the muxer writes one moof/mdat
1327 pair for each track, making it easier to separate tracks.
1329 This option is implicitly set when writing ismv (Smooth Streaming) files.
1330 @item -movflags faststart
1331 Run a second pass moving the index (moov atom) to the beginning of the file.
1332 This operation can take a while, and will not work in various situations such
1333 as fragmented output, thus it is not enabled by default.
1334 @item -movflags rtphint
1335 Add RTP hinting tracks to the output file.
1336 @item -movflags disable_chpl
1337 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
1338 and a QuickTime chapter track are written to the file. With this option
1339 set, only the QuickTime chapter track will be written. Nero chapters can
1340 cause failures when the file is reprocessed with certain tagging programs, like
1341 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
1342 @item -movflags omit_tfhd_offset
1343 Do not write any absolute base_data_offset in tfhd atoms. This avoids
1344 tying fragments to absolute byte positions in the file/streams.
1345 @item -movflags default_base_moof
1346 Similarly to the omit_tfhd_offset, this flag avoids writing the
1347 absolute base_data_offset field in tfhd atoms, but does so by using
1348 the new default-base-is-moof flag instead. This flag is new from
1349 14496-12:2012. This may make the fragments easier to parse in certain
1350 circumstances (avoiding basing track fragment location calculations
1351 on the implicit end of the previous track fragment).
1353 Specify @code{on} to force writing a timecode track, @code{off} to disable it
1354 and @code{auto} to write a timecode track only for mov and mp4 output (default).
1355 @item -movflags negative_cts_offsets
1356 Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
1357 be negative. This enables the initial sample to have DTS/CTS of zero, and
1358 reduces the need for edit lists for some cases such as video tracks with
1359 B-frames. Additionally, eases conformance with the DASH-IF interoperability
1362 This option is implicitly set when writing ismv (Smooth Streaming) files.
1364 Write producer time reference box (PRFT) with a specified time source for the
1365 NTP field in the PRFT box. Set value as @samp{wallclock} to specify timesource
1366 as wallclock time and @samp{pts} to specify timesource as input packets' PTS
1369 Setting value to @samp{pts} is applicable only for a live encoding use case,
1370 where PTS values are set as as wallclock time at the source. For example, an
1371 encoding use case with decklink capture source where @option{video_pts} and
1372 @option{audio_pts} are set to @samp{abs_wallclock}.
1377 Smooth Streaming content can be pushed in real time to a publishing
1378 point on IIS with this muxer. Example:
1380 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
1383 @subsection Audible AAX
1385 Audible AAX files are encrypted M4B files, and they can be decrypted by specifying a 4 byte activation secret.
1387 ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
1392 The MP3 muxer writes a raw MP3 stream with the following optional features:
1395 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
1396 2.4 are supported, the @code{id3v2_version} private option controls which one is
1397 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
1400 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
1401 The pictures are supplied to the muxer in form of a video stream with a single
1402 packet. There can be any number of those streams, each will correspond to a
1403 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
1404 to APIC @var{description} and @var{picture type} respectively. See
1405 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
1407 Note that the APIC frames must be written at the beginning, so the muxer will
1408 buffer the audio frames until it gets all the pictures. It is therefore advised
1409 to provide the pictures as soon as possible to avoid excessive buffering.
1412 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
1413 default, but will be written only if the output is seekable. The
1414 @code{write_xing} private option can be used to disable it. The frame contains
1415 various information that may be useful to the decoder, like the audio duration
1419 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1420 enabled with the @code{write_id3v1} private option, but as its capabilities are
1421 very limited, its usage is not recommended.
1426 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1428 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1431 To attach a picture to an mp3 file select both the audio and the picture stream
1434 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1435 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1438 Write a "clean" MP3 without any extra features:
1440 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1445 MPEG transport stream muxer.
1447 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1449 The recognized metadata settings in mpegts muxer are @code{service_provider}
1450 and @code{service_name}. If they are not set the default for
1451 @code{service_provider} is @samp{FFmpeg} and the default for
1452 @code{service_name} is @samp{Service01}.
1456 The muxer options are:
1459 @item mpegts_transport_stream_id @var{integer}
1460 Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
1461 Default is @code{0x0001}.
1463 @item mpegts_original_network_id @var{integer}
1464 Set the @samp{original_network_id}. This is unique identifier of a
1465 network in DVB. Its main use is in the unique identification of a service
1466 through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
1469 @item mpegts_service_id @var{integer}
1470 Set the @samp{service_id}, also known as program in DVB. Default is
1473 @item mpegts_service_type @var{integer}
1474 Set the program @samp{service_type}. Default is @code{digital_tv}.
1475 Accepts the following options:
1478 Any hexdecimal value between @code{0x01} to @code{0xff} as defined in
1483 Digital Radio service.
1486 @item advanced_codec_digital_radio
1487 Advanced Codec Digital Radio service.
1488 @item mpeg2_digital_hdtv
1489 MPEG2 Digital HDTV service.
1490 @item advanced_codec_digital_sdtv
1491 Advanced Codec Digital SDTV service.
1492 @item advanced_codec_digital_hdtv
1493 Advanced Codec Digital HDTV service.
1496 @item mpegts_pmt_start_pid @var{integer}
1497 Set the first PID for PMT. Default is @code{0x1000}. Max is @code{0x1f00}.
1499 @item mpegts_start_pid @var{integer}
1500 Set the first PID for data packets. Default is @code{0x0100}. Max is
1503 @item mpegts_m2ts_mode @var{boolean}
1504 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
1507 @item muxrate @var{integer}
1508 Set a constant muxrate. Default is VBR.
1510 @item pes_payload_size @var{integer}
1511 Set minimum PES packet payload in bytes. Default is @code{2930}.
1513 @item mpegts_flags @var{flags}
1514 Set mpegts flags. Accepts the following options:
1516 @item resend_headers
1517 Reemit PAT/PMT before writing the next packet.
1519 Use LATM packetization for AAC.
1520 @item pat_pmt_at_frames
1521 Reemit PAT and PMT at each video frame.
1523 Conform to System B (DVB) instead of System A (ATSC).
1524 @item initial_discontinuity
1525 Mark the initial packet of each stream as discontinuity.
1528 @item resend_headers @var{integer}
1529 Reemit PAT/PMT before writing the next packet. This option is deprecated:
1530 use @option{mpegts_flags} instead.
1532 @item mpegts_copyts @var{boolean}
1533 Preserve original timestamps, if value is set to @code{1}. Default value
1534 is @code{-1}, which results in shifting timestamps so that they start from 0.
1536 @item omit_video_pes_length @var{boolean}
1537 Omit the PES packet length for video packets. Default is @code{1} (true).
1539 @item pcr_period @var{integer}
1540 Override the default PCR retransmission time in milliseconds. Ignored if
1541 variable muxrate is selected. Default is @code{20}.
1543 @item pat_period @var{double}
1544 Maximum time in seconds between PAT/PMT tables.
1546 @item sdt_period @var{double}
1547 Maximum time in seconds between SDT tables.
1549 @item tables_version @var{integer}
1550 Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
1551 This option allows updating stream structure so that standard consumer may
1552 detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
1553 usage) or restart @command{ffmpeg} instance, cyclically changing
1554 @option{tables_version} value:
1557 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1558 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1560 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1561 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1562 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1570 ffmpeg -i file.mpg -c copy \
1571 -mpegts_original_network_id 0x1122 \
1572 -mpegts_transport_stream_id 0x3344 \
1573 -mpegts_service_id 0x5566 \
1574 -mpegts_pmt_start_pid 0x1500 \
1575 -mpegts_start_pid 0x150 \
1576 -metadata service_provider="Some provider" \
1577 -metadata service_name="Some Channel" \
1581 @section mxf, mxf_d10
1587 The muxer options are:
1590 @item store_user_comments @var{bool}
1591 Set if user comments should be stored if available or never.
1592 IRT D-10 does not allow user comments. The default is thus to write them for
1593 mxf but not for mxf_d10
1600 This muxer does not generate any output file, it is mainly useful for
1601 testing or benchmarking purposes.
1603 For example to benchmark decoding with @command{ffmpeg} you can use the
1606 ffmpeg -benchmark -i INPUT -f null out.null
1609 Note that the above command does not read or write the @file{out.null}
1610 file, but specifying the output file is required by the @command{ffmpeg}
1613 Alternatively you can write the command as:
1615 ffmpeg -benchmark -i INPUT -f null -
1621 @item -syncpoints @var{flags}
1622 Change the syncpoint usage in nut:
1624 @item @var{default} use the normal low-overhead seeking aids.
1625 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1626 Use of this option is not recommended, as the resulting files are very damage
1627 sensitive and seeking is not possible. Also in general the overhead from
1628 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1629 all growing data tables, allowing to mux endless streams with limited memory
1630 and without these disadvantages.
1631 @item @var{timestamped} extend the syncpoint with a wallclock field.
1633 The @var{none} and @var{timestamped} flags are experimental.
1634 @item -write_index @var{bool}
1635 Write index at the end, the default is to write an index.
1639 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1644 Ogg container muxer.
1647 @item -page_duration @var{duration}
1648 Preferred page duration, in microseconds. The muxer will attempt to create
1649 pages that are approximately @var{duration} microseconds long. This allows the
1650 user to compromise between seek granularity and container overhead. The default
1651 is 1 second. A value of 0 will fill all segments, making pages as large as
1652 possible. A value of 1 will effectively use 1 packet-per-page in most
1653 situations, giving a small seek granularity at the cost of additional container
1655 @item -serial_offset @var{value}
1656 Serial value from which to set the streams serial number.
1657 Setting it to different and sufficiently large values ensures that the produced
1658 ogg files can be safely chained.
1663 @section segment, stream_segment, ssegment
1665 Basic stream segmenter.
1667 This muxer outputs streams to a number of separate files of nearly
1668 fixed duration. Output filename pattern can be set in a fashion
1669 similar to @ref{image2}, or by using a @code{strftime} template if
1670 the @option{strftime} option is enabled.
1672 @code{stream_segment} is a variant of the muxer used to write to
1673 streaming output formats, i.e. which do not require global headers,
1674 and is recommended for outputting e.g. to MPEG transport stream segments.
1675 @code{ssegment} is a shorter alias for @code{stream_segment}.
1677 Every segment starts with a keyframe of the selected reference stream,
1678 which is set through the @option{reference_stream} option.
1680 Note that if you want accurate splitting for a video file, you need to
1681 make the input key frames correspond to the exact splitting times
1682 expected by the segmenter, or the segment muxer will start the new
1683 segment with the key frame found next after the specified start
1686 The segment muxer works best with a single constant frame rate video.
1688 Optionally it can generate a list of the created segments, by setting
1689 the option @var{segment_list}. The list type is specified by the
1690 @var{segment_list_type} option. The entry filenames in the segment
1691 list are set by default to the basename of the corresponding segment
1694 See also the @ref{hls} muxer, which provides a more specific
1695 implementation for HLS segmentation.
1699 The segment muxer supports the following options:
1702 @item increment_tc @var{1|0}
1703 if set to @code{1}, increment timecode between each segment
1704 If this is selected, the input need to have
1705 a timecode in the first video stream. Default value is
1708 @item reference_stream @var{specifier}
1709 Set the reference stream, as specified by the string @var{specifier}.
1710 If @var{specifier} is set to @code{auto}, the reference is chosen
1711 automatically. Otherwise it must be a stream specifier (see the ``Stream
1712 specifiers'' chapter in the ffmpeg manual) which specifies the
1713 reference stream. The default value is @code{auto}.
1715 @item segment_format @var{format}
1716 Override the inner container format, by default it is guessed by the filename
1719 @item segment_format_options @var{options_list}
1720 Set output format options using a :-separated list of key=value
1721 parameters. Values containing the @code{:} special character must be
1724 @item segment_list @var{name}
1725 Generate also a listfile named @var{name}. If not specified no
1726 listfile is generated.
1728 @item segment_list_flags @var{flags}
1729 Set flags affecting the segment list generation.
1731 It currently supports the following flags:
1734 Allow caching (only affects M3U8 list files).
1737 Allow live-friendly file generation.
1740 @item segment_list_size @var{size}
1741 Update the list file so that it contains at most @var{size}
1742 segments. If 0 the list file will contain all the segments. Default
1745 @item segment_list_entry_prefix @var{prefix}
1746 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1747 By default no prefix is applied.
1749 @item segment_list_type @var{type}
1750 Select the listing format.
1752 The following values are recognized:
1755 Generate a flat list for the created segments, one segment per line.
1758 Generate a list for the created segments, one segment per line,
1759 each line matching the format (comma-separated values):
1761 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1764 @var{segment_filename} is the name of the output file generated by the
1765 muxer according to the provided pattern. CSV escaping (according to
1766 RFC4180) is applied if required.
1768 @var{segment_start_time} and @var{segment_end_time} specify
1769 the segment start and end time expressed in seconds.
1771 A list file with the suffix @code{".csv"} or @code{".ext"} will
1772 auto-select this format.
1774 @samp{ext} is deprecated in favor or @samp{csv}.
1777 Generate an ffconcat file for the created segments. The resulting file
1778 can be read using the FFmpeg @ref{concat} demuxer.
1780 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1781 auto-select this format.
1784 Generate an extended M3U8 file, version 3, compliant with
1785 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1787 A list file with the suffix @code{".m3u8"} will auto-select this format.
1790 If not specified the type is guessed from the list file name suffix.
1792 @item segment_time @var{time}
1793 Set segment duration to @var{time}, the value must be a duration
1794 specification. Default value is "2". See also the
1795 @option{segment_times} option.
1797 Note that splitting may not be accurate, unless you force the
1798 reference stream key-frames at the given time. See the introductory
1799 notice and the examples below.
1801 @item segment_atclocktime @var{1|0}
1802 If set to "1" split at regular clock time intervals starting from 00:00
1803 o'clock. The @var{time} value specified in @option{segment_time} is
1804 used for setting the length of the splitting interval.
1806 For example with @option{segment_time} set to "900" this makes it possible
1807 to create files at 12:00 o'clock, 12:15, 12:30, etc.
1809 Default value is "0".
1811 @item segment_clocktime_offset @var{duration}
1812 Delay the segment splitting times with the specified duration when using
1813 @option{segment_atclocktime}.
1815 For example with @option{segment_time} set to "900" and
1816 @option{segment_clocktime_offset} set to "300" this makes it possible to
1817 create files at 12:05, 12:20, 12:35, etc.
1819 Default value is "0".
1821 @item segment_clocktime_wrap_duration @var{duration}
1822 Force the segmenter to only start a new segment if a packet reaches the muxer
1823 within the specified duration after the segmenting clock time. This way you
1824 can make the segmenter more resilient to backward local time jumps, such as
1825 leap seconds or transition to standard time from daylight savings time.
1827 Default is the maximum possible duration which means starting a new segment
1828 regardless of the elapsed time since the last clock time.
1830 @item segment_time_delta @var{delta}
1831 Specify the accuracy time when selecting the start time for a
1832 segment, expressed as a duration specification. Default value is "0".
1834 When delta is specified a key-frame will start a new segment if its
1835 PTS satisfies the relation:
1837 PTS >= start_time - time_delta
1840 This option is useful when splitting video content, which is always
1841 split at GOP boundaries, in case a key frame is found just before the
1842 specified split time.
1844 In particular may be used in combination with the @file{ffmpeg} option
1845 @var{force_key_frames}. The key frame times specified by
1846 @var{force_key_frames} may not be set accurately because of rounding
1847 issues, with the consequence that a key frame time may result set just
1848 before the specified time. For constant frame rate videos a value of
1849 1/(2*@var{frame_rate}) should address the worst case mismatch between
1850 the specified time and the time set by @var{force_key_frames}.
1852 @item segment_times @var{times}
1853 Specify a list of split points. @var{times} contains a list of comma
1854 separated duration specifications, in increasing order. See also
1855 the @option{segment_time} option.
1857 @item segment_frames @var{frames}
1858 Specify a list of split video frame numbers. @var{frames} contains a
1859 list of comma separated integer numbers, in increasing order.
1861 This option specifies to start a new segment whenever a reference
1862 stream key frame is found and the sequential number (starting from 0)
1863 of the frame is greater or equal to the next value in the list.
1865 @item segment_wrap @var{limit}
1866 Wrap around segment index once it reaches @var{limit}.
1868 @item segment_start_number @var{number}
1869 Set the sequence number of the first segment. Defaults to @code{0}.
1871 @item strftime @var{1|0}
1872 Use the @code{strftime} function to define the name of the new
1873 segments to write. If this is selected, the output segment name must
1874 contain a @code{strftime} function template. Default value is
1877 @item break_non_keyframes @var{1|0}
1878 If enabled, allow segments to start on frames other than keyframes. This
1879 improves behavior on some players when the time between keyframes is
1880 inconsistent, but may make things worse on others, and can cause some oddities
1881 during seeking. Defaults to @code{0}.
1883 @item reset_timestamps @var{1|0}
1884 Reset timestamps at the beginning of each segment, so that each segment
1885 will start with near-zero timestamps. It is meant to ease the playback
1886 of the generated segments. May not work with some combinations of
1887 muxers/codecs. It is set to @code{0} by default.
1889 @item initial_offset @var{offset}
1890 Specify timestamp offset to apply to the output packet timestamps. The
1891 argument must be a time duration specification, and defaults to 0.
1893 @item write_empty_segments @var{1|0}
1894 If enabled, write an empty segment if there are no packets during the period a
1895 segment would usually span. Otherwise, the segment will be filled with the next
1896 packet written. Defaults to @code{0}.
1899 Make sure to require a closed GOP when encoding and to set the GOP
1900 size to fit your segment time constraint.
1902 @subsection Examples
1906 Remux the content of file @file{in.mkv} to a list of segments
1907 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
1908 generated segments to @file{out.list}:
1910 ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
1914 Segment input and set output format options for the output segments:
1916 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
1920 Segment the input file according to the split points specified by the
1921 @var{segment_times} option:
1923 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
1927 Use the @command{ffmpeg} @option{force_key_frames}
1928 option to force key frames in the input at the specified location, together
1929 with the segment option @option{segment_time_delta} to account for
1930 possible roundings operated when setting key frame times.
1932 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
1933 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
1935 In order to force key frames on the input file, transcoding is
1939 Segment the input file by splitting the input file according to the
1940 frame numbers sequence specified with the @option{segment_frames} option:
1942 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
1946 Convert the @file{in.mkv} to TS segments using the @code{libx264}
1947 and @code{aac} encoders:
1949 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
1953 Segment the input file, and create an M3U8 live playlist (can be used
1954 as live HLS source):
1956 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
1957 -segment_list_flags +live -segment_time 10 out%03d.mkv
1961 @section smoothstreaming
1963 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
1967 Specify the number of fragments kept in the manifest. Default 0 (keep all).
1969 @item extra_window_size
1970 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
1972 @item lookahead_count
1973 Specify the number of lookahead fragments. Default 2.
1975 @item min_frag_duration
1976 Specify the minimum fragment duration (in microseconds). Default 5000000.
1978 @item remove_at_exit
1979 Specify whether to remove all fragments when finished. Default 0 (do not remove).
1986 The fifo pseudo-muxer allows the separation of encoding and muxing by using
1987 first-in-first-out queue and running the actual muxer in a separate thread. This
1988 is especially useful in combination with the @ref{tee} muxer and can be used to
1989 send data to several destinations with different reliability/writing speed/latency.
1991 API users should be aware that callback functions (interrupt_callback,
1992 io_open and io_close) used within its AVFormatContext must be thread-safe.
1994 The behavior of the fifo muxer if the queue fills up or if the output fails is
2000 output can be transparently restarted with configurable delay between retries
2001 based on real time or time of the processed stream.
2004 encoding can be blocked during temporary failure, or continue transparently
2005 dropping packets in case fifo queue fills up.
2012 Specify the format name. Useful if it cannot be guessed from the
2016 Specify size of the queue (number of packets). Default value is 60.
2019 Specify format options for the underlying muxer. Muxer options can be specified
2020 as a list of @var{key}=@var{value} pairs separated by ':'.
2022 @item drop_pkts_on_overflow @var{bool}
2023 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
2024 rather than blocking the encoder. This makes it possible to continue streaming without
2025 delaying the input, at the cost of omitting part of the stream. By default
2026 this option is set to 0 (false), so in such cases the encoder will be blocked
2027 until the muxer processes some of the packets and none of them is lost.
2029 @item attempt_recovery @var{bool}
2030 If failure occurs, attempt to recover the output. This is especially useful
2031 when used with network output, since it makes it possible to restart streaming transparently.
2032 By default this option is set to 0 (false).
2034 @item max_recovery_attempts
2035 Sets maximum number of successive unsuccessful recovery attempts after which
2036 the output fails permanently. By default this option is set to 0 (unlimited).
2038 @item recovery_wait_time @var{duration}
2039 Waiting time before the next recovery attempt after previous unsuccessful
2040 recovery attempt. Default value is 5 seconds.
2042 @item recovery_wait_streamtime @var{bool}
2043 If set to 0 (false), the real time is used when waiting for the recovery
2044 attempt (i.e. the recovery will be attempted after at least
2045 recovery_wait_time seconds).
2046 If set to 1 (true), the time of the processed stream is taken into account
2047 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
2048 seconds of the stream is omitted).
2049 By default, this option is set to 0 (false).
2051 @item recover_any_error @var{bool}
2052 If set to 1 (true), recovery will be attempted regardless of type of the error
2053 causing the failure. By default this option is set to 0 (false) and in case of
2054 certain (usually permanent) errors the recovery is not attempted even when
2055 @var{attempt_recovery} is set to 1.
2057 @item restart_with_keyframe @var{bool}
2058 Specify whether to wait for the keyframe after recovering from
2059 queue overflow or failure. This option is set to 0 (false) by default.
2063 @subsection Examples
2068 Stream something to rtmp server, continue processing the stream at real-time
2069 rate even in case of temporary failure (network outage) and attempt to recover
2070 streaming every second indefinitely.
2072 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
2073 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
2081 The tee muxer can be used to write the same data to several outputs, such as files or streams.
2082 It can be used, for example, to stream a video over a network and save it to disk at the same time.
2084 It is different from specifying several outputs to the @command{ffmpeg}
2085 command-line tool. With the tee muxer, the audio and video data will be encoded only once.
2086 With conventional multiple outputs, multiple encoding operations in parallel are initiated,
2087 which can be a very expensive process. The tee muxer is not useful when using the libavformat API
2088 directly because it is then possible to feed the same packets to several muxers directly.
2090 Since the tee muxer does not represent any particular output format, ffmpeg cannot auto-select
2091 output streams. So all streams intended for output must be specified using @code{-map}. See
2094 Some encoders may need different options depending on the output format;
2095 the auto-detection of this can not work with the tee muxer, so they need to be explicitly specified.
2096 The main example is the @option{global_header} flag.
2098 The slave outputs are specified in the file name given to the muxer,
2099 separated by '|'. If any of the slave name contains the '|' separator,
2100 leading or trailing spaces or any special character, those must be
2101 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
2102 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
2108 @item use_fifo @var{bool}
2109 If set to 1, slave outputs will be processed in separate threads using the @ref{fifo}
2110 muxer. This allows to compensate for different speed/latency/reliability of
2111 outputs and setup transparent recovery. By default this feature is turned off.
2114 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
2118 Muxer options can be specified for each slave by prepending them as a list of
2119 @var{key}=@var{value} pairs separated by ':', between square brackets. If
2120 the options values contain a special character or the ':' separator, they
2121 must be escaped; note that this is a second level escaping.
2123 The following special options are also recognized:
2126 Specify the format name. Required if it cannot be guessed from the
2129 @item bsfs[/@var{spec}]
2130 Specify a list of bitstream filters to apply to the specified
2133 It is possible to specify to which streams a given bitstream filter
2134 applies, by appending a stream specifier to the option separated by
2135 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
2136 stream specifiers}).
2138 If the stream specifier is not specified, the bitstream filters will be
2139 applied to all streams in the output. This will cause that output operation
2140 to fail if the output contains streams to which the bitstream filter cannot
2141 be applied e.g. @code{h264_mp4toannexb} being applied to an output containing an audio stream.
2143 Options for a bitstream filter must be specified in the form of @code{opt=value}.
2145 Several bitstream filters can be specified, separated by ",".
2147 @item use_fifo @var{bool}
2148 This allows to override tee muxer use_fifo option for individual slave muxer.
2151 This allows to override tee muxer fifo_options for individual slave muxer.
2155 Select the streams that should be mapped to the slave output,
2156 specified by a stream specifier. If not specified, this defaults to
2157 all the mapped streams. This will cause that output operation to fail
2158 if the output format does not accept all mapped streams.
2160 You may use multiple stream specifiers separated by commas (@code{,}) e.g.: @code{a:0,v}
2163 Specify behaviour on output failure. This can be set to either @code{abort} (which is
2164 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
2165 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
2166 will continue without being affected.
2169 @subsection Examples
2173 Encode something and both archive it in a WebM file and stream it
2174 as MPEG-TS over UDP:
2176 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2177 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2181 As above, but continue streaming even if output to local file fails
2182 (for example local drive fills up):
2184 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2185 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2189 Use @command{ffmpeg} to encode the input, and send the output
2190 to three different destinations. The @code{dump_extra} bitstream
2191 filter is used to add extradata information to all the output video
2192 keyframes packets, as requested by the MPEG-TS format. The select
2193 option is applied to @file{out.aac} in order to make it contain only
2196 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2197 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
2201 As above, but select only stream @code{a:1} for the audio output. Note
2202 that a second level escaping must be performed, as ":" is a special
2203 character used to separate options.
2205 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2206 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
2210 @section webm_dash_manifest
2212 WebM DASH Manifest muxer.
2214 This muxer implements the WebM DASH Manifest specification to generate the DASH
2215 manifest XML. It also supports manifest generation for DASH live streams.
2217 For more information see:
2221 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
2223 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
2228 This muxer supports the following options:
2231 @item adaptation_sets
2232 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
2233 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
2234 audio and video streams. Any number of adaptation sets can be added using this option.
2237 Set this to 1 to create a live stream DASH Manifest. Default: 0.
2239 @item chunk_start_index
2240 Start index of the first chunk. This will go in the @samp{startNumber} attribute
2241 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
2243 @item chunk_duration_ms
2244 Duration of each chunk in milliseconds. This will go in the @samp{duration}
2245 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
2247 @item utc_timing_url
2248 URL of the page that will return the UTC timestamp in ISO format. This will go
2249 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
2252 @item time_shift_buffer_depth
2253 Smallest time (in seconds) shifting buffer for which any Representation is
2254 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
2255 attribute of the @samp{MPD} element. Default: 60.
2257 @item minimum_update_period
2258 Minimum update period (in seconds) of the manifest. This will go in the
2259 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
2265 ffmpeg -f webm_dash_manifest -i video1.webm \
2266 -f webm_dash_manifest -i video2.webm \
2267 -f webm_dash_manifest -i audio1.webm \
2268 -f webm_dash_manifest -i audio2.webm \
2269 -map 0 -map 1 -map 2 -map 3 \
2271 -f webm_dash_manifest \
2272 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
2278 WebM Live Chunk Muxer.
2280 This muxer writes out WebM headers and chunks as separate files which can be
2281 consumed by clients that support WebM Live streams via DASH.
2285 This muxer supports the following options:
2288 @item chunk_start_index
2289 Index of the first chunk (defaults to 0).
2292 Filename of the header where the initialization data will be written.
2294 @item audio_chunk_duration
2295 Duration of each audio chunk in milliseconds (defaults to 5000).
2300 ffmpeg -f v4l2 -i /dev/video0 \
2304 -s 640x360 -keyint_min 30 -g 30 \
2306 -header webm_live_video_360.hdr \
2307 -chunk_start_index 1 \
2308 webm_live_video_360_%d.chk \
2313 -header webm_live_audio_128.hdr \
2314 -chunk_start_index 1 \
2315 -audio_chunk_duration 1000 \
2316 webm_live_audio_128_%d.chk