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, which generates
100 a fingerprint for the provided audio data. It takes a single signed
101 native-endian 16-bit raw audio stream.
106 @item silence_threshold
107 Threshold for detecting silence, ranges from 0 to 32767. -1 for default
108 (required for use with the AcoustID service).
111 Algorithm index to fingerprint with.
114 Format to output the fingerprint as. Accepts the following options:
117 Binary raw fingerprint
120 Binary compressed fingerprint
123 Base64 compressed fingerprint
132 CRC (Cyclic Redundancy Check) testing format.
134 This muxer computes and prints the Adler-32 CRC of all the input audio
135 and video frames. By default audio frames are converted to signed
136 16-bit raw audio and video frames to raw video before computing the
139 The output of the muxer consists of a single line of the form:
140 CRC=0x@var{CRC}, where @var{CRC} is a hexadecimal number 0-padded to
141 8 digits containing the CRC for all the decoded input frames.
143 See also the @ref{framecrc} muxer.
147 For example to compute the CRC of the input, and store it in the file
150 ffmpeg -i INPUT -f crc out.crc
153 You can print the CRC to stdout with the command:
155 ffmpeg -i INPUT -f crc -
158 You can select the output format of each frame with @command{ffmpeg} by
159 specifying the audio and video codec and format. For example to
160 compute the CRC of the input audio converted to PCM unsigned 8-bit
161 and the input video converted to MPEG-2 video, use the command:
163 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f crc -
168 Adobe Flash Video Format muxer.
170 This muxer accepts the following options:
174 @item flvflags @var{flags}
179 @item aac_seq_header_detect
180 Place AAC sequence header based on audio stream data.
182 @item no_sequence_end
183 Disable sequence end tag.
186 Disable metadata tag.
188 @item no_duration_filesize
189 Disable duration and filesize in metadata when they are equal to zero
190 at the end of stream. (Be used to non-seekable living stream).
192 @item add_keyframe_index
193 Used to facilitate seeking; particularly for HTTP pseudo streaming.
200 Dynamic Adaptive Streaming over HTTP (DASH) muxer that creates segments
201 and manifest files according to the MPEG-DASH standard ISO/IEC 23009-1:2014.
203 For more information see:
207 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
209 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
212 It creates a MPD manifest file and segment files for each stream.
214 The segment filename might contain pre-defined identifiers used with SegmentTemplate
215 as defined in section 5.3.9.4.4 of the standard. Available identifiers are "$RepresentationID$",
216 "$Number$", "$Bandwidth$" and "$Time$".
219 ffmpeg -re -i <input> -map 0 -map 0 -c:a libfdk_aac -c:v libx264
220 -b:v:0 800k -b:v:1 300k -s:v:1 320x170 -profile:v:1 baseline
221 -profile:v:0 main -bf 1 -keyint_min 120 -g 120 -sc_threshold 0
222 -b_strategy 0 -ar:a:1 22050 -use_timeline 1 -use_template 1
223 -window_size 5 -adaptation_sets "id=0,streams=v id=1,streams=a"
224 -f dash /path/to/out.mpd
228 @item -min_seg_duration @var{microseconds}
229 Set the segment length in microseconds.
230 @item -window_size @var{size}
231 Set the maximum number of segments kept in the manifest.
232 @item -extra_window_size @var{size}
233 Set the maximum number of segments kept outside of the manifest before removing from disk.
234 @item -remove_at_exit @var{remove}
235 Enable (1) or disable (0) removal of all segments when finished.
236 @item -use_template @var{template}
237 Enable (1) or disable (0) use of SegmentTemplate instead of SegmentList.
238 @item -use_timeline @var{timeline}
239 Enable (1) or disable (0) use of SegmentTimeline in SegmentTemplate.
240 @item -single_file @var{single_file}
241 Enable (1) or disable (0) storing all segments in one file, accessed using byte ranges.
242 @item -single_file_name @var{file_name}
243 DASH-templated name to be used for baseURL. Implies @var{single_file} set to "1".
244 @item -init_seg_name @var{init_name}
245 DASH-templated name to used for the initialization segment. Default is "init-stream$RepresentationID$.m4s"
246 @item -media_seg_name @var{segment_name}
247 DASH-templated name to used for the media segments. Default is "chunk-stream$RepresentationID$-$Number%05d$.m4s"
248 @item -utc_timing_url @var{utc_url}
249 URL of the page that will return the UTC timestamp in ISO format. Example: "https://time.akamai.com/?iso"
250 @item -adaptation_sets @var{adaptation_sets}
251 Assign streams to AdaptationSets. Syntax is "id=x,streams=a,b,c id=y,streams=d,e" with x and y being the IDs
252 of the adaptation sets and a,b,c,d and e are the indices of the mapped streams.
254 To map all video (or audio) streams to an AdaptationSet, "v" (or "a") can be used as stream identifier instead of IDs.
256 When no assignment is defined, this defaults to an AdaptationSet for each stream.
262 Per-packet CRC (Cyclic Redundancy Check) testing format.
264 This muxer computes and prints the Adler-32 CRC for each audio
265 and video packet. By default audio frames are converted to signed
266 16-bit raw audio and video frames to raw video before computing the
269 The output of the muxer consists of a line for each audio and video
272 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
275 @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
280 For example to compute the CRC of the audio and video frames in
281 @file{INPUT}, converted to raw audio and video packets, and store it
282 in the file @file{out.crc}:
284 ffmpeg -i INPUT -f framecrc out.crc
287 To print the information to stdout, use the command:
289 ffmpeg -i INPUT -f framecrc -
292 With @command{ffmpeg}, you can select the output format to which the
293 audio and video frames are encoded before computing the CRC for each
294 packet by specifying the audio and video codec. For example, to
295 compute the CRC of each decoded input audio frame converted to PCM
296 unsigned 8-bit and of each decoded input video frame converted to
297 MPEG-2 video, use the command:
299 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
302 See also the @ref{crc} muxer.
307 Per-packet hash testing format.
309 This muxer computes and prints a cryptographic hash for each audio
310 and video packet. This can be used for packet-by-packet equality
311 checks without having to individually do a binary comparison on each.
313 By default audio frames are converted to signed 16-bit raw audio and
314 video frames to raw video before computing the hash, but the output
315 of explicit conversions to other codecs can also be used. It uses the
316 SHA-256 cryptographic hash function by default, but supports several
319 The output of the muxer consists of a line for each audio and video
322 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
325 @var{hash} is a hexadecimal number representing the computed hash
329 @item hash @var{algorithm}
330 Use the cryptographic hash function specified by the string @var{algorithm}.
331 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
332 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
333 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
334 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
340 To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
341 converted to raw audio and video packets, and store it in the file
344 ffmpeg -i INPUT -f framehash out.sha256
347 To print the information to stdout, using the MD5 hash function, use
350 ffmpeg -i INPUT -f framehash -hash md5 -
353 See also the @ref{hash} muxer.
358 Per-packet MD5 testing format.
360 This is a variant of the @ref{framehash} muxer. Unlike that muxer,
361 it defaults to using the MD5 hash function.
365 To compute the MD5 hash of the audio and video frames in @file{INPUT},
366 converted to raw audio and video packets, and store it in the file
369 ffmpeg -i INPUT -f framemd5 out.md5
372 To print the information to stdout, use the command:
374 ffmpeg -i INPUT -f framemd5 -
377 See also the @ref{framehash} and @ref{md5} muxers.
384 It accepts the following options:
388 Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
389 for looping indefinitely (default).
392 Force the delay (expressed in centiseconds) after the last frame. Each frame
393 ends with a delay until the next frame. The default is @code{-1}, which is a
394 special value to tell the muxer to re-use the previous delay. In case of a
395 loop, you might want to customize this value to mark a pause for instance.
398 For example, to encode a gif looping 10 times, with a 5 seconds delay between
401 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
404 Note 1: if you wish to extract the frames into separate GIF files, you need to
405 force the @ref{image2} muxer:
407 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
410 Note 2: the GIF format has a very large time base: the delay between two frames
411 can therefore not be smaller than one centi second.
418 This muxer computes and prints a cryptographic hash of all the input
419 audio and video frames. This can be used for equality checks without
420 having to do a complete binary comparison.
422 By default audio frames are converted to signed 16-bit raw audio and
423 video frames to raw video before computing the hash, but the output
424 of explicit conversions to other codecs can also be used. Timestamps
425 are ignored. It uses the SHA-256 cryptographic hash function by default,
426 but supports several other algorithms.
428 The output of the muxer consists of a single line of the form:
429 @var{algo}=@var{hash}, where @var{algo} is a short string representing
430 the hash function used, and @var{hash} is a hexadecimal number
431 representing the computed hash.
434 @item hash @var{algorithm}
435 Use the cryptographic hash function specified by the string @var{algorithm}.
436 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
437 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
438 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
439 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
445 To compute the SHA-256 hash of the input converted to raw audio and
446 video, and store it in the file @file{out.sha256}:
448 ffmpeg -i INPUT -f hash out.sha256
451 To print an MD5 hash to stdout use the command:
453 ffmpeg -i INPUT -f hash -hash md5 -
456 See also the @ref{framehash} muxer.
461 Apple HTTP Live Streaming muxer that segments MPEG-TS according to
462 the HTTP Live Streaming (HLS) specification.
464 It creates a playlist file, and one or more segment files. The output filename
465 specifies the playlist filename.
467 By default, the muxer creates a file for each segment produced. These files
468 have the same name as the playlist, followed by a sequential number and a
471 For example, to convert an input file with @command{ffmpeg}:
473 ffmpeg -i in.nut out.m3u8
475 This example will produce the playlist, @file{out.m3u8}, and segment files:
476 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
478 See also the @ref{segment} muxer, which provides a more generic and
479 flexible implementation of a segmenter, and can be used to perform HLS
484 This muxer supports the following options:
487 @item hls_init_time @var{seconds}
488 Set the initial target segment length in seconds. Default value is @var{0}.
489 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
490 After the initial playlist is filled @command{ffmpeg} will cut segments
491 at duration equal to @code{hls_time}
493 @item hls_time @var{seconds}
494 Set the target segment length in seconds. Default value is 2.
495 Segment will be cut on the next key frame after this time has passed.
497 @item hls_list_size @var{size}
498 Set the maximum number of playlist entries. If set to 0 the list file
499 will contain all the segments. Default value is 5.
501 @item hls_ts_options @var{options_list}
502 Set output format options using a :-separated list of key=value
503 parameters. Values containing @code{:} special characters must be
506 @item hls_wrap @var{wrap}
507 This is a deprecated option, you can use @code{hls_list_size}
508 and @code{hls_flags delete_segments} instead it
510 This option is useful to avoid to fill the disk with many segment
511 files, and limits the maximum number of segment files written to disk
515 @item hls_start_number_source
516 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
517 Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
518 segment and subtitle filenames. In any case, if @code{hls_flags append_list}
519 is set and read playlist sequence number is greater than the specified start sequence number,
520 then that value will be used as start value.
522 It accepts the following values:
526 @item generic (default)
527 Set the starting sequence numbers according to @var{start_number} option value.
530 The start number will be the seconds since epoch (1970-01-01 00:00:00)
533 The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
537 @item start_number @var{number}
538 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
539 when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
540 Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
543 @item hls_allow_cache @var{allowcache}
544 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
546 @item hls_base_url @var{baseurl}
547 Append @var{baseurl} to every entry in the playlist.
548 Useful to generate playlists with absolute paths.
550 Note that the playlist sequence number must be unique for each segment
551 and it is not to be confused with the segment filename sequence number
552 which can be cyclic, for example if the @option{wrap} option is
555 @item hls_segment_filename @var{filename}
556 Set the segment filename. Unless @code{hls_flags single_file} is set,
557 @var{filename} is used as a string format with the segment number:
559 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
561 This example will produce the playlist, @file{out.m3u8}, and segment files:
562 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
564 @var{filename} may contain full path or relative path specification,
565 but only the file name part without any path info will be contained in the m3u8 segment list.
566 Should a relative path be specified, the path of the created segment
567 files will be relative to the current working directory.
568 When use_localtime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
572 Use strftime() on @var{filename} to expand the segment filename with localtime.
573 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
574 hls_flag and %%d will be the specifier.
576 ffmpeg -i in.nut -use_localtime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
578 This example will produce the playlist, @file{out.m3u8}, and segment files:
579 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
580 Note: On some systems/environments, the @code{%s} specifier is not available. See
581 @code{strftime()} documentation.
583 ffmpeg -i in.nut -use_localtime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
585 This example will produce the playlist, @file{out.m3u8}, and segment files:
586 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
588 @item use_localtime_mkdir
589 Used together with -use_localtime, it will create all subdirectories which
590 is expanded in @var{filename}.
592 ffmpeg -i in.nut -use_localtime 1 -use_localtime_mkdir 1 -hls_segment_filename '%Y%m%d/file-%Y%m%d-%s.ts' out.m3u8
594 This example will create a directory 201560215 (if it does not exist), and then
595 produce the playlist, @file{out.m3u8}, and segment files:
596 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
599 ffmpeg -i in.nut -use_localtime 1 -use_localtime_mkdir 1 -hls_segment_filename '%Y/%m/%d/file-%Y%m%d-%s.ts' out.m3u8
601 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
602 produce the playlist, @file{out.m3u8}, and segment files:
603 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
606 @item hls_key_info_file @var{key_info_file}
607 Use the information in @var{key_info_file} for segment encryption. The first
608 line of @var{key_info_file} specifies the key URI written to the playlist. The
609 key URL is used to access the encryption key during playback. The second line
610 specifies the path to the key file used to obtain the key during the encryption
611 process. The key file is read as a single packed array of 16 octets in binary
612 format. The optional third line specifies the initialization vector (IV) as a
613 hexadecimal string to be used instead of the segment sequence number (default)
614 for encryption. Changes to @var{key_info_file} will result in segment
615 encryption with the new key/IV and an entry in the playlist for the new key
616 URI/IV if @code{hls_flags periodic_rekey} is enabled.
618 Key info file format:
627 http://server/file.key
632 Example key file paths:
640 0123456789ABCDEF0123456789ABCDEF
643 Key info file example:
645 http://server/file.key
647 0123456789ABCDEF0123456789ABCDEF
650 Example shell script:
654 openssl rand 16 > file.key
655 echo $BASE_URL/file.key > file.keyinfo
656 echo file.key >> file.keyinfo
657 echo $(openssl rand -hex 16) >> file.keyinfo
658 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
659 -hls_key_info_file file.keyinfo out.m3u8
662 @item -hls_enc @var{enc}
663 Enable (1) or disable (0) the AES128 encryption.
664 When enabled every segment generated is encrypted and the encryption key
665 is saved as @var{playlist name}.key.
667 @item -hls_enc_key @var{key}
668 Hex-coded 16byte key to encrypt the segments, by default it
669 is randomly generated.
671 @item -hls_enc_key_url @var{keyurl}
672 If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
675 @item -hls_enc_iv @var{iv}
676 Hex-coded 16byte initialization vector for every segment instead
677 of the autogenerated ones.
679 @item hls_segment_type @var{flags}
684 If this flag is set, the hls segment files will format to mpegts.
685 the mpegts files is used in all hls versions.
688 If this flag is set, the hls segment files will format to fragment mp4 looks like dash.
689 the fmp4 files is used in hls after version 7.
693 @item hls_fmp4_init_filename @var{filename}
694 set filename to the fragment files header file, default filename is @file{init.mp4}.
696 @item hls_flags @var{flags}
701 If this flag is set, the muxer will store all segments in a single MPEG-TS
702 file, and will use byte ranges in the playlist. HLS playlists generated with
703 this way will have the version number 4.
706 ffmpeg -i in.nut -hls_flags single_file out.m3u8
708 Will produce the playlist, @file{out.m3u8}, and a single segment file,
711 @item delete_segments
712 Segment files removed from the playlist are deleted after a period of time
713 equal to the duration of the segment plus the duration of the playlist.
716 Append new segments into the end of old segment list,
717 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
719 @item round_durations
720 Round the duration info in the playlist file segment info to integer
721 values, instead of using floating point.
724 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
725 first segment's information.
728 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
731 The file specified by @code{hls_key_info_file} will be checked periodically and
732 detect updates to the encryption info. Be sure to replace this file atomically,
733 including the file containing the AES encryption key.
736 Allow segments to start on frames other than keyframes. This improves
737 behavior on some players when the time between keyframes is inconsistent,
738 but may make things worse on others, and can cause some oddities during
739 seeking. This flag should be used with the @code{hls_time} option.
741 @item program_date_time
742 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
744 @item second_level_segment_index
745 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
746 besides date/time values when use_localtime is on.
747 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
749 @item second_level_segment_size
750 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
751 expression besides date/time values when use_localtime is on.
752 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
754 @item second_level_segment_duration
755 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
756 expression besides date/time values when use_localtime is on.
757 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
760 ffmpeg -i sample.mpeg \
761 -f hls -hls_time 3 -hls_list_size 5 \
762 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
763 -use_localtime 1 -use_localtime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
765 This will produce segments like this:
766 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
769 Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
770 serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
771 before they have been added to the m3u8 playlist.
775 @item hls_playlist_type event
776 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
777 @option{hls_list_size} to 0; the playlist can only be appended to.
779 @item hls_playlist_type vod
780 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
781 @option{hls_list_size} to 0; the playlist must not change.
784 Use the given HTTP method to create the hls files.
786 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
788 This example will upload all the mpegts segment files to the HTTP
789 server using the HTTP PUT method, and update the m3u8 files every
790 @code{refresh} times using the same method.
791 Note that the HTTP server must support the given method for uploading
794 @item http_user_agent
795 Override User-Agent field in HTTP header. Applicable only for HTTP output.
804 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
808 Size cannot exceed 256 pixels in any dimension
811 Only BMP and PNG images can be stored
814 If a BMP image is used, it must be one of the following pixel formats:
816 BMP Bit Depth FFmpeg Pixel Format
826 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
829 If a PNG image is used, it must use the rgba pixel format
837 The image file muxer writes video frames to image files.
839 The output filenames are specified by a pattern, which can be used to
840 produce sequentially numbered series of files.
841 The pattern may contain the string "%d" or "%0@var{N}d", this string
842 specifies the position of the characters representing a numbering in
843 the filenames. If the form "%0@var{N}d" is used, the string
844 representing the number in each filename is 0-padded to @var{N}
845 digits. The literal character '%' can be specified in the pattern with
848 If the pattern contains "%d" or "%0@var{N}d", the first filename of
849 the file list specified will contain the number 1, all the following
850 numbers will be sequential.
852 The pattern may contain a suffix which is used to automatically
853 determine the format of the image files to write.
855 For example the pattern "img-%03d.bmp" will specify a sequence of
856 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
857 @file{img-010.bmp}, etc.
858 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
859 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
864 The following example shows how to use @command{ffmpeg} for creating a
865 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
866 taking one image every second from the input video:
868 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
871 Note that with @command{ffmpeg}, if the format is not specified with the
872 @code{-f} option and the output filename specifies an image file
873 format, the image2 muxer is automatically selected, so the previous
874 command can be written as:
876 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
879 Note also that the pattern must not necessarily contain "%d" or
880 "%0@var{N}d", for example to create a single image file
881 @file{img.jpeg} from the start of the input video you can employ the command:
883 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
886 The @option{strftime} option allows you to expand the filename with
887 date and time information. Check the documentation of
888 the @code{strftime()} function for the syntax.
890 For example to generate image files from the @code{strftime()}
891 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
894 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
901 Start the sequence from the specified number. Default value is 1.
904 If set to 1, the filename will always be interpreted as just a
905 filename, not a pattern, and the corresponding file will be continuously
906 overwritten with new images. Default value is 0.
909 If set to 1, expand the filename with date and time information from
910 @code{strftime()}. Default value is 0.
913 The image muxer supports the .Y.U.V image file format. This format is
914 special in that that each image frame consists of three files, for
915 each of the YUV420P components. To read or write this image file format,
916 specify the name of the '.Y' file. The muxer will automatically open the
917 '.U' and '.V' files as required.
921 Matroska container muxer.
923 This muxer implements the matroska and webm container specs.
927 The recognized metadata settings in this muxer are:
931 Set title name provided to a single track.
934 Specify the language of the track in the Matroska languages form.
936 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
937 639-2/B) form (like "fre" for French), or a language code mixed with a
938 country code for specialities in languages (like "fre-ca" for Canadian
942 Set stereo 3D video layout of two views in a single video track.
944 The following values are recognized:
949 Both views are arranged side by side, Left-eye view is on the left
951 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
953 Both views are arranged in top-bottom orientation, Left-eye view is on top
954 @item checkerboard_rl
955 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
956 @item checkerboard_lr
957 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
958 @item row_interleaved_rl
959 Each view is constituted by a row based interleaving, Right-eye view is first row
960 @item row_interleaved_lr
961 Each view is constituted by a row based interleaving, Left-eye view is first row
962 @item col_interleaved_rl
963 Both views are arranged in a column based interleaving manner, Right-eye view is first column
964 @item col_interleaved_lr
965 Both views are arranged in a column based interleaving manner, Left-eye view is first column
966 @item anaglyph_cyan_red
967 All frames are in anaglyph format viewable through red-cyan filters
969 Both views are arranged side by side, Right-eye view is on the left
970 @item anaglyph_green_magenta
971 All frames are in anaglyph format viewable through green-magenta filters
973 Both eyes laced in one Block, Left-eye view is first
975 Both eyes laced in one Block, Right-eye view is first
979 For example a 3D WebM clip can be created using the following command line:
981 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
986 This muxer supports the following options:
989 @item reserve_index_space
990 By default, this muxer writes the index for seeking (called cues in Matroska
991 terms) at the end of the file, because it cannot know in advance how much space
992 to leave for the index at the beginning of the file. However for some use cases
993 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
994 index at the beginning of the file.
996 If this option is set to a non-zero value, the muxer will reserve a given amount
997 of space in the file header and then try to write the cues there when the muxing
998 finishes. If the available space does not suffice, muxing will fail. A safe size
999 for most use cases should be about 50kB per hour of video.
1001 Note that cues are only written if the output is seekable and this option will
1002 have no effect if it is not.
1010 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
1011 defaults to using the MD5 hash function.
1013 @subsection Examples
1015 To compute the MD5 hash of the input converted to raw
1016 audio and video, and store it in the file @file{out.md5}:
1018 ffmpeg -i INPUT -f md5 out.md5
1021 You can print the MD5 to stdout with the command:
1023 ffmpeg -i INPUT -f md5 -
1026 See also the @ref{hash} and @ref{framemd5} muxers.
1028 @section mov, mp4, ismv
1030 MOV/MP4/ISMV (Smooth Streaming) muxer.
1032 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
1033 file has all the metadata about all packets stored in one location
1034 (written at the end of the file, it can be moved to the start for
1035 better playback by adding @var{faststart} to the @var{movflags}, or
1036 using the @command{qt-faststart} tool). A fragmented
1037 file consists of a number of fragments, where packets and metadata
1038 about these packets are stored together. Writing a fragmented
1039 file has the advantage that the file is decodable even if the
1040 writing is interrupted (while a normal MOV/MP4 is undecodable if
1041 it is not properly finished), and it requires less memory when writing
1042 very long files (since writing normal MOV/MP4 files stores info about
1043 every single packet in memory until the file is closed). The downside
1044 is that it is less compatible with other applications.
1048 Fragmentation is enabled by setting one of the AVOptions that define
1049 how to cut the file into fragments:
1052 @item -moov_size @var{bytes}
1053 Reserves space for the moov atom at the beginning of the file instead of placing the
1054 moov atom at the end. If the space reserved is insufficient, muxing will fail.
1055 @item -movflags frag_keyframe
1056 Start a new fragment at each video keyframe.
1057 @item -frag_duration @var{duration}
1058 Create fragments that are @var{duration} microseconds long.
1059 @item -frag_size @var{size}
1060 Create fragments that contain up to @var{size} bytes of payload data.
1061 @item -movflags frag_custom
1062 Allow the caller to manually choose when to cut fragments, by
1063 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
1064 the packets written so far. (This is only useful with other
1065 applications integrating libavformat, not from @command{ffmpeg}.)
1066 @item -min_frag_duration @var{duration}
1067 Don't create fragments that are shorter than @var{duration} microseconds long.
1070 If more than one condition is specified, fragments are cut when
1071 one of the specified conditions is fulfilled. The exception to this is
1072 @code{-min_frag_duration}, which has to be fulfilled for any of the other
1073 conditions to apply.
1075 Additionally, the way the output file is written can be adjusted
1076 through a few other options:
1079 @item -movflags empty_moov
1080 Write an initial moov atom directly at the start of the file, without
1081 describing any samples in it. Generally, an mdat/moov pair is written
1082 at the start of the file, as a normal MOV/MP4 file, containing only
1083 a short portion of the file. With this option set, there is no initial
1084 mdat atom, and the moov atom only describes the tracks but has
1087 This option is implicitly set when writing ismv (Smooth Streaming) files.
1088 @item -movflags separate_moof
1089 Write a separate moof (movie fragment) atom for each track. Normally,
1090 packets for all tracks are written in a moof atom (which is slightly
1091 more efficient), but with this option set, the muxer writes one moof/mdat
1092 pair for each track, making it easier to separate tracks.
1094 This option is implicitly set when writing ismv (Smooth Streaming) files.
1095 @item -movflags faststart
1096 Run a second pass moving the index (moov atom) to the beginning of the file.
1097 This operation can take a while, and will not work in various situations such
1098 as fragmented output, thus it is not enabled by default.
1099 @item -movflags rtphint
1100 Add RTP hinting tracks to the output file.
1101 @item -movflags disable_chpl
1102 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
1103 and a QuickTime chapter track are written to the file. With this option
1104 set, only the QuickTime chapter track will be written. Nero chapters can
1105 cause failures when the file is reprocessed with certain tagging programs, like
1106 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
1107 @item -movflags omit_tfhd_offset
1108 Do not write any absolute base_data_offset in tfhd atoms. This avoids
1109 tying fragments to absolute byte positions in the file/streams.
1110 @item -movflags default_base_moof
1111 Similarly to the omit_tfhd_offset, this flag avoids writing the
1112 absolute base_data_offset field in tfhd atoms, but does so by using
1113 the new default-base-is-moof flag instead. This flag is new from
1114 14496-12:2012. This may make the fragments easier to parse in certain
1115 circumstances (avoiding basing track fragment location calculations
1116 on the implicit end of the previous track fragment).
1118 Specify @code{on} to force writing a timecode track, @code{off} to disable it
1119 and @code{auto} to write a timecode track only for mov and mp4 output (default).
1124 Smooth Streaming content can be pushed in real time to a publishing
1125 point on IIS with this muxer. Example:
1127 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
1130 @subsection Audible AAX
1132 Audible AAX files are encrypted M4B files, and they can be decrypted by specifying a 4 byte activation secret.
1134 ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
1139 The MP3 muxer writes a raw MP3 stream with the following optional features:
1142 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
1143 2.4 are supported, the @code{id3v2_version} private option controls which one is
1144 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
1147 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
1148 The pictures are supplied to the muxer in form of a video stream with a single
1149 packet. There can be any number of those streams, each will correspond to a
1150 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
1151 to APIC @var{description} and @var{picture type} respectively. See
1152 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
1154 Note that the APIC frames must be written at the beginning, so the muxer will
1155 buffer the audio frames until it gets all the pictures. It is therefore advised
1156 to provide the pictures as soon as possible to avoid excessive buffering.
1159 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
1160 default, but will be written only if the output is seekable. The
1161 @code{write_xing} private option can be used to disable it. The frame contains
1162 various information that may be useful to the decoder, like the audio duration
1166 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1167 enabled with the @code{write_id3v1} private option, but as its capabilities are
1168 very limited, its usage is not recommended.
1173 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1175 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1178 To attach a picture to an mp3 file select both the audio and the picture stream
1181 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1182 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1185 Write a "clean" MP3 without any extra features:
1187 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1192 MPEG transport stream muxer.
1194 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1196 The recognized metadata settings in mpegts muxer are @code{service_provider}
1197 and @code{service_name}. If they are not set the default for
1198 @code{service_provider} is @samp{FFmpeg} and the default for
1199 @code{service_name} is @samp{Service01}.
1203 The muxer options are:
1206 @item mpegts_transport_stream_id @var{integer}
1207 Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
1208 Default is @code{0x0001}.
1210 @item mpegts_original_network_id @var{integer}
1211 Set the @samp{original_network_id}. This is unique identifier of a
1212 network in DVB. Its main use is in the unique identification of a service
1213 through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
1216 @item mpegts_service_id @var{integer}
1217 Set the @samp{service_id}, also known as program in DVB. Default is
1220 @item mpegts_service_type @var{integer}
1221 Set the program @samp{service_type}. Default is @code{digital_tv}.
1222 Accepts the following options:
1225 Any hexdecimal value between @code{0x01} to @code{0xff} as defined in
1230 Digital Radio service.
1233 @item advanced_codec_digital_radio
1234 Advanced Codec Digital Radio service.
1235 @item mpeg2_digital_hdtv
1236 MPEG2 Digital HDTV service.
1237 @item advanced_codec_digital_sdtv
1238 Advanced Codec Digital SDTV service.
1239 @item advanced_codec_digital_hdtv
1240 Advanced Codec Digital HDTV service.
1243 @item mpegts_pmt_start_pid @var{integer}
1244 Set the first PID for PMT. Default is @code{0x1000}. Max is @code{0x1f00}.
1246 @item mpegts_start_pid @var{integer}
1247 Set the first PID for data packets. Default is @code{0x0100}. Max is
1250 @item mpegts_m2ts_mode @var{boolean}
1251 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
1254 @item muxrate @var{integer}
1255 Set a constant muxrate. Default is VBR.
1257 @item pes_payload_size @var{integer}
1258 Set minimum PES packet payload in bytes. Default is @code{2930}.
1260 @item mpegts_flags @var{flags}
1261 Set mpegts flags. Accepts the following options:
1263 @item resend_headers
1264 Reemit PAT/PMT before writing the next packet.
1266 Use LATM packetization for AAC.
1267 @item pat_pmt_at_frames
1268 Reemit PAT and PMT at each video frame.
1270 Conform to System B (DVB) instead of System A (ATSC).
1271 @item initial_discontinuity
1272 Mark the initial packet of each stream as discontinuity.
1275 @item resend_headers @var{integer}
1276 Reemit PAT/PMT before writing the next packet. This option is deprecated:
1277 use @option{mpegts_flags} instead.
1279 @item mpegts_copyts @var{boolean}
1280 Preserve original timestamps, if value is set to @code{1}. Default value
1281 is @code{-1}, which results in shifting timestamps so that they start from 0.
1283 @item omit_video_pes_length @var{boolean}
1284 Omit the PES packet length for video packets. Default is @code{1} (true).
1286 @item pcr_period @var{integer}
1287 Override the default PCR retransmission time in milliseconds. Ignored if
1288 variable muxrate is selected. Default is @code{20}.
1290 @item pat_period @var{double}
1291 Maximum time in seconds between PAT/PMT tables.
1293 @item sdt_period @var{double}
1294 Maximum time in seconds between SDT tables.
1296 @item tables_version @var{integer}
1297 Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
1298 This option allows updating stream structure so that standard consumer may
1299 detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
1300 usage) or restart @command{ffmpeg} instance, cyclically changing
1301 @option{tables_version} value:
1304 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1305 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1307 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1308 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1309 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1317 ffmpeg -i file.mpg -c copy \
1318 -mpegts_original_network_id 0x1122 \
1319 -mpegts_transport_stream_id 0x3344 \
1320 -mpegts_service_id 0x5566 \
1321 -mpegts_pmt_start_pid 0x1500 \
1322 -mpegts_start_pid 0x150 \
1323 -metadata service_provider="Some provider" \
1324 -metadata service_name="Some Channel" \
1328 @section mxf, mxf_d10
1334 The muxer options are:
1337 @item store_user_comments @var{bool}
1338 Set if user comments should be stored if available or never.
1339 IRT D-10 does not allow user comments. The default is thus to write them for
1340 mxf but not for mxf_d10
1347 This muxer does not generate any output file, it is mainly useful for
1348 testing or benchmarking purposes.
1350 For example to benchmark decoding with @command{ffmpeg} you can use the
1353 ffmpeg -benchmark -i INPUT -f null out.null
1356 Note that the above command does not read or write the @file{out.null}
1357 file, but specifying the output file is required by the @command{ffmpeg}
1360 Alternatively you can write the command as:
1362 ffmpeg -benchmark -i INPUT -f null -
1368 @item -syncpoints @var{flags}
1369 Change the syncpoint usage in nut:
1371 @item @var{default} use the normal low-overhead seeking aids.
1372 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1373 Use of this option is not recommended, as the resulting files are very damage
1374 sensitive and seeking is not possible. Also in general the overhead from
1375 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1376 all growing data tables, allowing to mux endless streams with limited memory
1377 and without these disadvantages.
1378 @item @var{timestamped} extend the syncpoint with a wallclock field.
1380 The @var{none} and @var{timestamped} flags are experimental.
1381 @item -write_index @var{bool}
1382 Write index at the end, the default is to write an index.
1386 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1391 Ogg container muxer.
1394 @item -page_duration @var{duration}
1395 Preferred page duration, in microseconds. The muxer will attempt to create
1396 pages that are approximately @var{duration} microseconds long. This allows the
1397 user to compromise between seek granularity and container overhead. The default
1398 is 1 second. A value of 0 will fill all segments, making pages as large as
1399 possible. A value of 1 will effectively use 1 packet-per-page in most
1400 situations, giving a small seek granularity at the cost of additional container
1402 @item -serial_offset @var{value}
1403 Serial value from which to set the streams serial number.
1404 Setting it to different and sufficiently large values ensures that the produced
1405 ogg files can be safely chained.
1410 @section segment, stream_segment, ssegment
1412 Basic stream segmenter.
1414 This muxer outputs streams to a number of separate files of nearly
1415 fixed duration. Output filename pattern can be set in a fashion
1416 similar to @ref{image2}, or by using a @code{strftime} template if
1417 the @option{strftime} option is enabled.
1419 @code{stream_segment} is a variant of the muxer used to write to
1420 streaming output formats, i.e. which do not require global headers,
1421 and is recommended for outputting e.g. to MPEG transport stream segments.
1422 @code{ssegment} is a shorter alias for @code{stream_segment}.
1424 Every segment starts with a keyframe of the selected reference stream,
1425 which is set through the @option{reference_stream} option.
1427 Note that if you want accurate splitting for a video file, you need to
1428 make the input key frames correspond to the exact splitting times
1429 expected by the segmenter, or the segment muxer will start the new
1430 segment with the key frame found next after the specified start
1433 The segment muxer works best with a single constant frame rate video.
1435 Optionally it can generate a list of the created segments, by setting
1436 the option @var{segment_list}. The list type is specified by the
1437 @var{segment_list_type} option. The entry filenames in the segment
1438 list are set by default to the basename of the corresponding segment
1441 See also the @ref{hls} muxer, which provides a more specific
1442 implementation for HLS segmentation.
1446 The segment muxer supports the following options:
1449 @item increment_tc @var{1|0}
1450 if set to @code{1}, increment timecode between each segment
1451 If this is selected, the input need to have
1452 a timecode in the first video stream. Default value is
1455 @item reference_stream @var{specifier}
1456 Set the reference stream, as specified by the string @var{specifier}.
1457 If @var{specifier} is set to @code{auto}, the reference is chosen
1458 automatically. Otherwise it must be a stream specifier (see the ``Stream
1459 specifiers'' chapter in the ffmpeg manual) which specifies the
1460 reference stream. The default value is @code{auto}.
1462 @item segment_format @var{format}
1463 Override the inner container format, by default it is guessed by the filename
1466 @item segment_format_options @var{options_list}
1467 Set output format options using a :-separated list of key=value
1468 parameters. Values containing the @code{:} special character must be
1471 @item segment_list @var{name}
1472 Generate also a listfile named @var{name}. If not specified no
1473 listfile is generated.
1475 @item segment_list_flags @var{flags}
1476 Set flags affecting the segment list generation.
1478 It currently supports the following flags:
1481 Allow caching (only affects M3U8 list files).
1484 Allow live-friendly file generation.
1487 @item segment_list_size @var{size}
1488 Update the list file so that it contains at most @var{size}
1489 segments. If 0 the list file will contain all the segments. Default
1492 @item segment_list_entry_prefix @var{prefix}
1493 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1494 By default no prefix is applied.
1496 @item segment_list_type @var{type}
1497 Select the listing format.
1499 The following values are recognized:
1502 Generate a flat list for the created segments, one segment per line.
1505 Generate a list for the created segments, one segment per line,
1506 each line matching the format (comma-separated values):
1508 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1511 @var{segment_filename} is the name of the output file generated by the
1512 muxer according to the provided pattern. CSV escaping (according to
1513 RFC4180) is applied if required.
1515 @var{segment_start_time} and @var{segment_end_time} specify
1516 the segment start and end time expressed in seconds.
1518 A list file with the suffix @code{".csv"} or @code{".ext"} will
1519 auto-select this format.
1521 @samp{ext} is deprecated in favor or @samp{csv}.
1524 Generate an ffconcat file for the created segments. The resulting file
1525 can be read using the FFmpeg @ref{concat} demuxer.
1527 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1528 auto-select this format.
1531 Generate an extended M3U8 file, version 3, compliant with
1532 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1534 A list file with the suffix @code{".m3u8"} will auto-select this format.
1537 If not specified the type is guessed from the list file name suffix.
1539 @item segment_time @var{time}
1540 Set segment duration to @var{time}, the value must be a duration
1541 specification. Default value is "2". See also the
1542 @option{segment_times} option.
1544 Note that splitting may not be accurate, unless you force the
1545 reference stream key-frames at the given time. See the introductory
1546 notice and the examples below.
1548 @item segment_atclocktime @var{1|0}
1549 If set to "1" split at regular clock time intervals starting from 00:00
1550 o'clock. The @var{time} value specified in @option{segment_time} is
1551 used for setting the length of the splitting interval.
1553 For example with @option{segment_time} set to "900" this makes it possible
1554 to create files at 12:00 o'clock, 12:15, 12:30, etc.
1556 Default value is "0".
1558 @item segment_clocktime_offset @var{duration}
1559 Delay the segment splitting times with the specified duration when using
1560 @option{segment_atclocktime}.
1562 For example with @option{segment_time} set to "900" and
1563 @option{segment_clocktime_offset} set to "300" this makes it possible to
1564 create files at 12:05, 12:20, 12:35, etc.
1566 Default value is "0".
1568 @item segment_clocktime_wrap_duration @var{duration}
1569 Force the segmenter to only start a new segment if a packet reaches the muxer
1570 within the specified duration after the segmenting clock time. This way you
1571 can make the segmenter more resilient to backward local time jumps, such as
1572 leap seconds or transition to standard time from daylight savings time.
1574 Default is the maximum possible duration which means starting a new segment
1575 regardless of the elapsed time since the last clock time.
1577 @item segment_time_delta @var{delta}
1578 Specify the accuracy time when selecting the start time for a
1579 segment, expressed as a duration specification. Default value is "0".
1581 When delta is specified a key-frame will start a new segment if its
1582 PTS satisfies the relation:
1584 PTS >= start_time - time_delta
1587 This option is useful when splitting video content, which is always
1588 split at GOP boundaries, in case a key frame is found just before the
1589 specified split time.
1591 In particular may be used in combination with the @file{ffmpeg} option
1592 @var{force_key_frames}. The key frame times specified by
1593 @var{force_key_frames} may not be set accurately because of rounding
1594 issues, with the consequence that a key frame time may result set just
1595 before the specified time. For constant frame rate videos a value of
1596 1/(2*@var{frame_rate}) should address the worst case mismatch between
1597 the specified time and the time set by @var{force_key_frames}.
1599 @item segment_times @var{times}
1600 Specify a list of split points. @var{times} contains a list of comma
1601 separated duration specifications, in increasing order. See also
1602 the @option{segment_time} option.
1604 @item segment_frames @var{frames}
1605 Specify a list of split video frame numbers. @var{frames} contains a
1606 list of comma separated integer numbers, in increasing order.
1608 This option specifies to start a new segment whenever a reference
1609 stream key frame is found and the sequential number (starting from 0)
1610 of the frame is greater or equal to the next value in the list.
1612 @item segment_wrap @var{limit}
1613 Wrap around segment index once it reaches @var{limit}.
1615 @item segment_start_number @var{number}
1616 Set the sequence number of the first segment. Defaults to @code{0}.
1618 @item strftime @var{1|0}
1619 Use the @code{strftime} function to define the name of the new
1620 segments to write. If this is selected, the output segment name must
1621 contain a @code{strftime} function template. Default value is
1624 @item break_non_keyframes @var{1|0}
1625 If enabled, allow segments to start on frames other than keyframes. This
1626 improves behavior on some players when the time between keyframes is
1627 inconsistent, but may make things worse on others, and can cause some oddities
1628 during seeking. Defaults to @code{0}.
1630 @item reset_timestamps @var{1|0}
1631 Reset timestamps at the beginning of each segment, so that each segment
1632 will start with near-zero timestamps. It is meant to ease the playback
1633 of the generated segments. May not work with some combinations of
1634 muxers/codecs. It is set to @code{0} by default.
1636 @item initial_offset @var{offset}
1637 Specify timestamp offset to apply to the output packet timestamps. The
1638 argument must be a time duration specification, and defaults to 0.
1640 @item write_empty_segments @var{1|0}
1641 If enabled, write an empty segment if there are no packets during the period a
1642 segment would usually span. Otherwise, the segment will be filled with the next
1643 packet written. Defaults to @code{0}.
1646 @subsection Examples
1650 Remux the content of file @file{in.mkv} to a list of segments
1651 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
1652 generated segments to @file{out.list}:
1654 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.list out%03d.nut
1658 Segment input and set output format options for the output segments:
1660 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
1664 Segment the input file according to the split points specified by the
1665 @var{segment_times} option:
1667 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
1671 Use the @command{ffmpeg} @option{force_key_frames}
1672 option to force key frames in the input at the specified location, together
1673 with the segment option @option{segment_time_delta} to account for
1674 possible roundings operated when setting key frame times.
1676 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
1677 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
1679 In order to force key frames on the input file, transcoding is
1683 Segment the input file by splitting the input file according to the
1684 frame numbers sequence specified with the @option{segment_frames} option:
1686 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
1690 Convert the @file{in.mkv} to TS segments using the @code{libx264}
1691 and @code{aac} encoders:
1693 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
1697 Segment the input file, and create an M3U8 live playlist (can be used
1698 as live HLS source):
1700 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
1701 -segment_list_flags +live -segment_time 10 out%03d.mkv
1705 @section smoothstreaming
1707 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
1711 Specify the number of fragments kept in the manifest. Default 0 (keep all).
1713 @item extra_window_size
1714 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
1716 @item lookahead_count
1717 Specify the number of lookahead fragments. Default 2.
1719 @item min_frag_duration
1720 Specify the minimum fragment duration (in microseconds). Default 5000000.
1722 @item remove_at_exit
1723 Specify whether to remove all fragments when finished. Default 0 (do not remove).
1730 The fifo pseudo-muxer allows the separation of encoding and muxing by using
1731 first-in-first-out queue and running the actual muxer in a separate thread. This
1732 is especially useful in combination with the @ref{tee} muxer and can be used to
1733 send data to several destinations with different reliability/writing speed/latency.
1735 API users should be aware that callback functions (interrupt_callback,
1736 io_open and io_close) used within its AVFormatContext must be thread-safe.
1738 The behavior of the fifo muxer if the queue fills up or if the output fails is
1744 output can be transparently restarted with configurable delay between retries
1745 based on real time or time of the processed stream.
1748 encoding can be blocked during temporary failure, or continue transparently
1749 dropping packets in case fifo queue fills up.
1756 Specify the format name. Useful if it cannot be guessed from the
1760 Specify size of the queue (number of packets). Default value is 60.
1763 Specify format options for the underlying muxer. Muxer options can be specified
1764 as a list of @var{key}=@var{value} pairs separated by ':'.
1766 @item drop_pkts_on_overflow @var{bool}
1767 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
1768 rather than blocking the encoder. This makes it possible to continue streaming without
1769 delaying the input, at the cost of omitting part of the stream. By default
1770 this option is set to 0 (false), so in such cases the encoder will be blocked
1771 until the muxer processes some of the packets and none of them is lost.
1773 @item attempt_recovery @var{bool}
1774 If failure occurs, attempt to recover the output. This is especially useful
1775 when used with network output, since it makes it possible to restart streaming transparently.
1776 By default this option is set to 0 (false).
1778 @item max_recovery_attempts
1779 Sets maximum number of successive unsuccessful recovery attempts after which
1780 the output fails permanently. By default this option is set to 0 (unlimited).
1782 @item recovery_wait_time @var{duration}
1783 Waiting time before the next recovery attempt after previous unsuccessful
1784 recovery attempt. Default value is 5 seconds.
1786 @item recovery_wait_streamtime @var{bool}
1787 If set to 0 (false), the real time is used when waiting for the recovery
1788 attempt (i.e. the recovery will be attempted after at least
1789 recovery_wait_time seconds).
1790 If set to 1 (true), the time of the processed stream is taken into account
1791 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
1792 seconds of the stream is omitted).
1793 By default, this option is set to 0 (false).
1795 @item recover_any_error @var{bool}
1796 If set to 1 (true), recovery will be attempted regardless of type of the error
1797 causing the failure. By default this option is set to 0 (false) and in case of
1798 certain (usually permanent) errors the recovery is not attempted even when
1799 @var{attempt_recovery} is set to 1.
1801 @item restart_with_keyframe @var{bool}
1802 Specify whether to wait for the keyframe after recovering from
1803 queue overflow or failure. This option is set to 0 (false) by default.
1807 @subsection Examples
1812 Stream something to rtmp server, continue processing the stream at real-time
1813 rate even in case of temporary failure (network outage) and attempt to recover
1814 streaming every second indefinitely.
1816 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
1817 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
1825 The tee muxer can be used to write the same data to several files or any
1826 other kind of muxer. It can be used, for example, to both stream a video to
1827 the network and save it to disk at the same time.
1829 It is different from specifying several outputs to the @command{ffmpeg}
1830 command-line tool because the audio and video data will be encoded only once
1831 with the tee muxer; encoding can be a very expensive process. It is not
1832 useful when using the libavformat API directly because it is then possible
1833 to feed the same packets to several muxers directly.
1837 @item use_fifo @var{bool}
1838 If set to 1, slave outputs will be processed in separate thread using @ref{fifo}
1839 muxer. This allows to compensate for different speed/latency/reliability of
1840 outputs and setup transparent recovery. By default this feature is turned off.
1843 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
1847 The slave outputs are specified in the file name given to the muxer,
1848 separated by '|'. If any of the slave name contains the '|' separator,
1849 leading or trailing spaces or any special character, it must be
1850 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
1851 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
1853 Muxer options can be specified for each slave by prepending them as a list of
1854 @var{key}=@var{value} pairs separated by ':', between square brackets. If
1855 the options values contain a special character or the ':' separator, they
1856 must be escaped; note that this is a second level escaping.
1858 The following special options are also recognized:
1861 Specify the format name. Useful if it cannot be guessed from the
1864 @item bsfs[/@var{spec}]
1865 Specify a list of bitstream filters to apply to the specified
1868 @item use_fifo @var{bool}
1869 This allows to override tee muxer use_fifo option for individual slave muxer.
1872 This allows to override tee muxer fifo_options for individual slave muxer.
1875 It is possible to specify to which streams a given bitstream filter
1876 applies, by appending a stream specifier to the option separated by
1877 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
1878 stream specifiers}). If the stream specifier is not specified, the
1879 bitstream filters will be applied to all streams in the output.
1881 Several bitstream filters can be specified, separated by ",".
1884 Select the streams that should be mapped to the slave output,
1885 specified by a stream specifier. If not specified, this defaults to
1886 all the input streams. You may use multiple stream specifiers
1887 separated by commas (@code{,}) e.g.: @code{a:0,v}
1890 Specify behaviour on output failure. This can be set to either @code{abort} (which is
1891 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
1892 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
1893 will continue without being affected.
1896 @subsection Examples
1900 Encode something and both archive it in a WebM file and stream it
1901 as MPEG-TS over UDP (the streams need to be explicitly mapped):
1903 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
1904 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
1908 As above, but continue streaming even if output to local file fails
1909 (for example local drive fills up):
1911 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
1912 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
1916 Use @command{ffmpeg} to encode the input, and send the output
1917 to three different destinations. The @code{dump_extra} bitstream
1918 filter is used to add extradata information to all the output video
1919 keyframes packets, as requested by the MPEG-TS format. The select
1920 option is applied to @file{out.aac} in order to make it contain only
1923 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
1924 -f tee "[bsfs/v=dump_extra]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
1928 As below, but select only stream @code{a:1} for the audio output. Note
1929 that a second level escaping must be performed, as ":" is a special
1930 character used to separate options.
1932 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
1933 -f tee "[bsfs/v=dump_extra]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
1937 Note: some codecs may need different options depending on the output format;
1938 the auto-detection of this can not work with the tee muxer. The main example
1939 is the @option{global_header} flag.
1941 @section webm_dash_manifest
1943 WebM DASH Manifest muxer.
1945 This muxer implements the WebM DASH Manifest specification to generate the DASH
1946 manifest XML. It also supports manifest generation for DASH live streams.
1948 For more information see:
1952 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
1954 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
1959 This muxer supports the following options:
1962 @item adaptation_sets
1963 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
1964 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
1965 audio and video streams. Any number of adaptation sets can be added using this option.
1968 Set this to 1 to create a live stream DASH Manifest. Default: 0.
1970 @item chunk_start_index
1971 Start index of the first chunk. This will go in the @samp{startNumber} attribute
1972 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
1974 @item chunk_duration_ms
1975 Duration of each chunk in milliseconds. This will go in the @samp{duration}
1976 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
1978 @item utc_timing_url
1979 URL of the page that will return the UTC timestamp in ISO format. This will go
1980 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
1983 @item time_shift_buffer_depth
1984 Smallest time (in seconds) shifting buffer for which any Representation is
1985 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
1986 attribute of the @samp{MPD} element. Default: 60.
1988 @item minimum_update_period
1989 Minimum update period (in seconds) of the manifest. This will go in the
1990 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
1996 ffmpeg -f webm_dash_manifest -i video1.webm \
1997 -f webm_dash_manifest -i video2.webm \
1998 -f webm_dash_manifest -i audio1.webm \
1999 -f webm_dash_manifest -i audio2.webm \
2000 -map 0 -map 1 -map 2 -map 3 \
2002 -f webm_dash_manifest \
2003 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
2009 WebM Live Chunk Muxer.
2011 This muxer writes out WebM headers and chunks as separate files which can be
2012 consumed by clients that support WebM Live streams via DASH.
2016 This muxer supports the following options:
2019 @item chunk_start_index
2020 Index of the first chunk (defaults to 0).
2023 Filename of the header where the initialization data will be written.
2025 @item audio_chunk_duration
2026 Duration of each audio chunk in milliseconds (defaults to 5000).
2031 ffmpeg -f v4l2 -i /dev/video0 \
2035 -s 640x360 -keyint_min 30 -g 30 \
2037 -header webm_live_video_360.hdr \
2038 -chunk_start_index 1 \
2039 webm_live_video_360_%d.chk \
2044 -header webm_live_audio_128.hdr \
2045 -chunk_start_index 1 \
2046 -audio_chunk_duration 1000 \
2047 webm_live_audio_128_%d.chk