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 Make sure to require a closed GOP when encoding and to set the GOP
472 size to fit your segment time constraint.
474 For example, to convert an input file with @command{ffmpeg}:
476 ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
478 This example will produce the playlist, @file{out.m3u8}, and segment files:
479 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
481 See also the @ref{segment} muxer, which provides a more generic and
482 flexible implementation of a segmenter, and can be used to perform HLS
487 This muxer supports the following options:
490 @item hls_init_time @var{seconds}
491 Set the initial target segment length in seconds. Default value is @var{0}.
492 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
493 After the initial playlist is filled @command{ffmpeg} will cut segments
494 at duration equal to @code{hls_time}
496 @item hls_time @var{seconds}
497 Set the target segment length in seconds. Default value is 2.
498 Segment will be cut on the next key frame after this time has passed.
500 @item hls_list_size @var{size}
501 Set the maximum number of playlist entries. If set to 0 the list file
502 will contain all the segments. Default value is 5.
504 @item hls_ts_options @var{options_list}
505 Set output format options using a :-separated list of key=value
506 parameters. Values containing @code{:} special characters must be
509 @item hls_wrap @var{wrap}
510 This is a deprecated option, you can use @code{hls_list_size}
511 and @code{hls_flags delete_segments} instead it
513 This option is useful to avoid to fill the disk with many segment
514 files, and limits the maximum number of segment files written to disk
518 @item hls_start_number_source
519 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
520 Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
521 segment and subtitle filenames. In any case, if @code{hls_flags append_list}
522 is set and read playlist sequence number is greater than the specified start sequence number,
523 then that value will be used as start value.
525 It accepts the following values:
529 @item generic (default)
530 Set the starting sequence numbers according to @var{start_number} option value.
533 The start number will be the seconds since epoch (1970-01-01 00:00:00)
536 The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
540 @item start_number @var{number}
541 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
542 when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
543 Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
546 @item hls_allow_cache @var{allowcache}
547 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
549 @item hls_base_url @var{baseurl}
550 Append @var{baseurl} to every entry in the playlist.
551 Useful to generate playlists with absolute paths.
553 Note that the playlist sequence number must be unique for each segment
554 and it is not to be confused with the segment filename sequence number
555 which can be cyclic, for example if the @option{wrap} option is
558 @item hls_segment_filename @var{filename}
559 Set the segment filename. Unless @code{hls_flags single_file} is set,
560 @var{filename} is used as a string format with the segment number:
562 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
564 This example will produce the playlist, @file{out.m3u8}, and segment files:
565 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
567 @var{filename} may contain full path or relative path specification,
568 but only the file name part without any path info will be contained in the m3u8 segment list.
569 Should a relative path be specified, the path of the created segment
570 files will be relative to the current working directory.
571 When use_localtime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
575 Use strftime() on @var{filename} to expand the segment filename with localtime.
576 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
577 hls_flag and %%d will be the specifier.
579 ffmpeg -i in.nut -use_localtime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
581 This example will produce the playlist, @file{out.m3u8}, and segment files:
582 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
583 Note: On some systems/environments, the @code{%s} specifier is not available. See
584 @code{strftime()} documentation.
586 ffmpeg -i in.nut -use_localtime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
588 This example will produce the playlist, @file{out.m3u8}, and segment files:
589 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
591 @item use_localtime_mkdir
592 Used together with -use_localtime, it will create all subdirectories which
593 is expanded in @var{filename}.
595 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
597 This example will create a directory 201560215 (if it does not exist), and then
598 produce the playlist, @file{out.m3u8}, and segment files:
599 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
602 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
604 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
605 produce the playlist, @file{out.m3u8}, and segment files:
606 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
609 @item hls_key_info_file @var{key_info_file}
610 Use the information in @var{key_info_file} for segment encryption. The first
611 line of @var{key_info_file} specifies the key URI written to the playlist. The
612 key URL is used to access the encryption key during playback. The second line
613 specifies the path to the key file used to obtain the key during the encryption
614 process. The key file is read as a single packed array of 16 octets in binary
615 format. The optional third line specifies the initialization vector (IV) as a
616 hexadecimal string to be used instead of the segment sequence number (default)
617 for encryption. Changes to @var{key_info_file} will result in segment
618 encryption with the new key/IV and an entry in the playlist for the new key
619 URI/IV if @code{hls_flags periodic_rekey} is enabled.
621 Key info file format:
630 http://server/file.key
635 Example key file paths:
643 0123456789ABCDEF0123456789ABCDEF
646 Key info file example:
648 http://server/file.key
650 0123456789ABCDEF0123456789ABCDEF
653 Example shell script:
657 openssl rand 16 > file.key
658 echo $BASE_URL/file.key > file.keyinfo
659 echo file.key >> file.keyinfo
660 echo $(openssl rand -hex 16) >> file.keyinfo
661 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
662 -hls_key_info_file file.keyinfo out.m3u8
665 @item -hls_enc @var{enc}
666 Enable (1) or disable (0) the AES128 encryption.
667 When enabled every segment generated is encrypted and the encryption key
668 is saved as @var{playlist name}.key.
670 @item -hls_enc_key @var{key}
671 Hex-coded 16byte key to encrypt the segments, by default it
672 is randomly generated.
674 @item -hls_enc_key_url @var{keyurl}
675 If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
678 @item -hls_enc_iv @var{iv}
679 Hex-coded 16byte initialization vector for every segment instead
680 of the autogenerated ones.
682 @item hls_segment_type @var{flags}
687 If this flag is set, the hls segment files will format to mpegts.
688 the mpegts files is used in all hls versions.
691 If this flag is set, the hls segment files will format to fragment mp4 looks like dash.
692 the fmp4 files is used in hls after version 7.
696 @item hls_fmp4_init_filename @var{filename}
697 set filename to the fragment files header file, default filename is @file{init.mp4}.
699 @item hls_flags @var{flags}
704 If this flag is set, the muxer will store all segments in a single MPEG-TS
705 file, and will use byte ranges in the playlist. HLS playlists generated with
706 this way will have the version number 4.
709 ffmpeg -i in.nut -hls_flags single_file out.m3u8
711 Will produce the playlist, @file{out.m3u8}, and a single segment file,
714 @item delete_segments
715 Segment files removed from the playlist are deleted after a period of time
716 equal to the duration of the segment plus the duration of the playlist.
719 Append new segments into the end of old segment list,
720 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
722 @item round_durations
723 Round the duration info in the playlist file segment info to integer
724 values, instead of using floating point.
727 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
728 first segment's information.
731 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
734 The file specified by @code{hls_key_info_file} will be checked periodically and
735 detect updates to the encryption info. Be sure to replace this file atomically,
736 including the file containing the AES encryption key.
739 Allow segments to start on frames other than keyframes. This improves
740 behavior on some players when the time between keyframes is inconsistent,
741 but may make things worse on others, and can cause some oddities during
742 seeking. This flag should be used with the @code{hls_time} option.
744 @item program_date_time
745 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
747 @item second_level_segment_index
748 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
749 besides date/time values when use_localtime is on.
750 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
752 @item second_level_segment_size
753 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
754 expression besides date/time values when use_localtime is on.
755 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
757 @item second_level_segment_duration
758 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
759 expression besides date/time values when use_localtime is on.
760 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
763 ffmpeg -i sample.mpeg \
764 -f hls -hls_time 3 -hls_list_size 5 \
765 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
766 -use_localtime 1 -use_localtime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
768 This will produce segments like this:
769 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
772 Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
773 serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
774 before they have been added to the m3u8 playlist.
778 @item hls_playlist_type event
779 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
780 @option{hls_list_size} to 0; the playlist can only be appended to.
782 @item hls_playlist_type vod
783 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
784 @option{hls_list_size} to 0; the playlist must not change.
787 Use the given HTTP method to create the hls files.
789 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
791 This example will upload all the mpegts segment files to the HTTP
792 server using the HTTP PUT method, and update the m3u8 files every
793 @code{refresh} times using the same method.
794 Note that the HTTP server must support the given method for uploading
797 @item http_user_agent
798 Override User-Agent field in HTTP header. Applicable only for HTTP output.
801 Map string which specifies how to group the audio, video and subtitle streams
802 into different variant streams. The variant stream groups are separated
804 Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
805 the keys to specify audio, video and subtitle streams respectively.
806 Allowed values are 0 to 9 (limited just based on practical usage).
809 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
810 -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" \
811 http://example.com/live/out.m3u8
813 This example creates two hls variant streams. The first variant stream will
814 contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
815 second variant stream will contain video stream of bitrate 256k and audio
816 stream of bitrate 32k. Here, two media playlist with file names out_1.m3u8 and
817 out_2.m3u8 will be created.
819 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
820 -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
821 http://example.com/live/out.m3u8
823 This example creates three hls variant streams. The first variant stream will
824 be a video only stream with video bitrate 1000k, the second variant stream will
825 be an audio only stream with bitrate 64k and the third variant stream will be a
826 video only stream with bitrate 256k. Here, three media playlist with file names
827 out_1.m3u8, out_2.m3u8 and out_3.m3u8 will be created.
829 By default, a single hls variant containing all the encoded streams is created.
832 Create HLS master playlist with the given name.
835 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
837 This example creates HLS master playlist with name master.m3u8 and it is
838 published at http://example.com/live/
840 @item master_pl_publish_rate
841 Publish master play list repeatedly every after specified number of segment intervals.
844 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
845 -hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
848 This example creates HLS master playlist with name master.m3u8 and keep
849 publishing it repeatedly every after 30 segments i.e. every after 60s.
858 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
862 Size cannot exceed 256 pixels in any dimension
865 Only BMP and PNG images can be stored
868 If a BMP image is used, it must be one of the following pixel formats:
870 BMP Bit Depth FFmpeg Pixel Format
880 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
883 If a PNG image is used, it must use the rgba pixel format
891 The image file muxer writes video frames to image files.
893 The output filenames are specified by a pattern, which can be used to
894 produce sequentially numbered series of files.
895 The pattern may contain the string "%d" or "%0@var{N}d", this string
896 specifies the position of the characters representing a numbering in
897 the filenames. If the form "%0@var{N}d" is used, the string
898 representing the number in each filename is 0-padded to @var{N}
899 digits. The literal character '%' can be specified in the pattern with
902 If the pattern contains "%d" or "%0@var{N}d", the first filename of
903 the file list specified will contain the number 1, all the following
904 numbers will be sequential.
906 The pattern may contain a suffix which is used to automatically
907 determine the format of the image files to write.
909 For example the pattern "img-%03d.bmp" will specify a sequence of
910 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
911 @file{img-010.bmp}, etc.
912 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
913 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
918 The following example shows how to use @command{ffmpeg} for creating a
919 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
920 taking one image every second from the input video:
922 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
925 Note that with @command{ffmpeg}, if the format is not specified with the
926 @code{-f} option and the output filename specifies an image file
927 format, the image2 muxer is automatically selected, so the previous
928 command can be written as:
930 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
933 Note also that the pattern must not necessarily contain "%d" or
934 "%0@var{N}d", for example to create a single image file
935 @file{img.jpeg} from the start of the input video you can employ the command:
937 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
940 The @option{strftime} option allows you to expand the filename with
941 date and time information. Check the documentation of
942 the @code{strftime()} function for the syntax.
944 For example to generate image files from the @code{strftime()}
945 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
948 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
951 You can set the file name with current frame's PTS:
953 ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
960 If set to 1, expand the filename with pts from pkt->pts.
964 Start the sequence from the specified number. Default value is 1.
967 If set to 1, the filename will always be interpreted as just a
968 filename, not a pattern, and the corresponding file will be continuously
969 overwritten with new images. Default value is 0.
972 If set to 1, expand the filename with date and time information from
973 @code{strftime()}. Default value is 0.
976 The image muxer supports the .Y.U.V image file format. This format is
977 special in that that each image frame consists of three files, for
978 each of the YUV420P components. To read or write this image file format,
979 specify the name of the '.Y' file. The muxer will automatically open the
980 '.U' and '.V' files as required.
984 Matroska container muxer.
986 This muxer implements the matroska and webm container specs.
990 The recognized metadata settings in this muxer are:
994 Set title name provided to a single track.
997 Specify the language of the track in the Matroska languages form.
999 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
1000 639-2/B) form (like "fre" for French), or a language code mixed with a
1001 country code for specialities in languages (like "fre-ca" for Canadian
1005 Set stereo 3D video layout of two views in a single video track.
1007 The following values are recognized:
1012 Both views are arranged side by side, Left-eye view is on the left
1014 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
1016 Both views are arranged in top-bottom orientation, Left-eye view is on top
1017 @item checkerboard_rl
1018 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
1019 @item checkerboard_lr
1020 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
1021 @item row_interleaved_rl
1022 Each view is constituted by a row based interleaving, Right-eye view is first row
1023 @item row_interleaved_lr
1024 Each view is constituted by a row based interleaving, Left-eye view is first row
1025 @item col_interleaved_rl
1026 Both views are arranged in a column based interleaving manner, Right-eye view is first column
1027 @item col_interleaved_lr
1028 Both views are arranged in a column based interleaving manner, Left-eye view is first column
1029 @item anaglyph_cyan_red
1030 All frames are in anaglyph format viewable through red-cyan filters
1032 Both views are arranged side by side, Right-eye view is on the left
1033 @item anaglyph_green_magenta
1034 All frames are in anaglyph format viewable through green-magenta filters
1036 Both eyes laced in one Block, Left-eye view is first
1038 Both eyes laced in one Block, Right-eye view is first
1042 For example a 3D WebM clip can be created using the following command line:
1044 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
1049 This muxer supports the following options:
1052 @item reserve_index_space
1053 By default, this muxer writes the index for seeking (called cues in Matroska
1054 terms) at the end of the file, because it cannot know in advance how much space
1055 to leave for the index at the beginning of the file. However for some use cases
1056 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
1057 index at the beginning of the file.
1059 If this option is set to a non-zero value, the muxer will reserve a given amount
1060 of space in the file header and then try to write the cues there when the muxing
1061 finishes. If the available space does not suffice, muxing will fail. A safe size
1062 for most use cases should be about 50kB per hour of video.
1064 Note that cues are only written if the output is seekable and this option will
1065 have no effect if it is not.
1073 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
1074 defaults to using the MD5 hash function.
1076 @subsection Examples
1078 To compute the MD5 hash of the input converted to raw
1079 audio and video, and store it in the file @file{out.md5}:
1081 ffmpeg -i INPUT -f md5 out.md5
1084 You can print the MD5 to stdout with the command:
1086 ffmpeg -i INPUT -f md5 -
1089 See also the @ref{hash} and @ref{framemd5} muxers.
1091 @section mov, mp4, ismv
1093 MOV/MP4/ISMV (Smooth Streaming) muxer.
1095 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
1096 file has all the metadata about all packets stored in one location
1097 (written at the end of the file, it can be moved to the start for
1098 better playback by adding @var{faststart} to the @var{movflags}, or
1099 using the @command{qt-faststart} tool). A fragmented
1100 file consists of a number of fragments, where packets and metadata
1101 about these packets are stored together. Writing a fragmented
1102 file has the advantage that the file is decodable even if the
1103 writing is interrupted (while a normal MOV/MP4 is undecodable if
1104 it is not properly finished), and it requires less memory when writing
1105 very long files (since writing normal MOV/MP4 files stores info about
1106 every single packet in memory until the file is closed). The downside
1107 is that it is less compatible with other applications.
1111 Fragmentation is enabled by setting one of the AVOptions that define
1112 how to cut the file into fragments:
1115 @item -moov_size @var{bytes}
1116 Reserves space for the moov atom at the beginning of the file instead of placing the
1117 moov atom at the end. If the space reserved is insufficient, muxing will fail.
1118 @item -movflags frag_keyframe
1119 Start a new fragment at each video keyframe.
1120 @item -frag_duration @var{duration}
1121 Create fragments that are @var{duration} microseconds long.
1122 @item -frag_size @var{size}
1123 Create fragments that contain up to @var{size} bytes of payload data.
1124 @item -movflags frag_custom
1125 Allow the caller to manually choose when to cut fragments, by
1126 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
1127 the packets written so far. (This is only useful with other
1128 applications integrating libavformat, not from @command{ffmpeg}.)
1129 @item -min_frag_duration @var{duration}
1130 Don't create fragments that are shorter than @var{duration} microseconds long.
1133 If more than one condition is specified, fragments are cut when
1134 one of the specified conditions is fulfilled. The exception to this is
1135 @code{-min_frag_duration}, which has to be fulfilled for any of the other
1136 conditions to apply.
1138 Additionally, the way the output file is written can be adjusted
1139 through a few other options:
1142 @item -movflags empty_moov
1143 Write an initial moov atom directly at the start of the file, without
1144 describing any samples in it. Generally, an mdat/moov pair is written
1145 at the start of the file, as a normal MOV/MP4 file, containing only
1146 a short portion of the file. With this option set, there is no initial
1147 mdat atom, and the moov atom only describes the tracks but has
1150 This option is implicitly set when writing ismv (Smooth Streaming) files.
1151 @item -movflags separate_moof
1152 Write a separate moof (movie fragment) atom for each track. Normally,
1153 packets for all tracks are written in a moof atom (which is slightly
1154 more efficient), but with this option set, the muxer writes one moof/mdat
1155 pair for each track, making it easier to separate tracks.
1157 This option is implicitly set when writing ismv (Smooth Streaming) files.
1158 @item -movflags faststart
1159 Run a second pass moving the index (moov atom) to the beginning of the file.
1160 This operation can take a while, and will not work in various situations such
1161 as fragmented output, thus it is not enabled by default.
1162 @item -movflags rtphint
1163 Add RTP hinting tracks to the output file.
1164 @item -movflags disable_chpl
1165 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
1166 and a QuickTime chapter track are written to the file. With this option
1167 set, only the QuickTime chapter track will be written. Nero chapters can
1168 cause failures when the file is reprocessed with certain tagging programs, like
1169 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
1170 @item -movflags omit_tfhd_offset
1171 Do not write any absolute base_data_offset in tfhd atoms. This avoids
1172 tying fragments to absolute byte positions in the file/streams.
1173 @item -movflags default_base_moof
1174 Similarly to the omit_tfhd_offset, this flag avoids writing the
1175 absolute base_data_offset field in tfhd atoms, but does so by using
1176 the new default-base-is-moof flag instead. This flag is new from
1177 14496-12:2012. This may make the fragments easier to parse in certain
1178 circumstances (avoiding basing track fragment location calculations
1179 on the implicit end of the previous track fragment).
1181 Specify @code{on} to force writing a timecode track, @code{off} to disable it
1182 and @code{auto} to write a timecode track only for mov and mp4 output (default).
1183 @item -movflags negative_cts_offsets
1184 Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
1185 be negative. This enables the initial sample to have DTS/CTS of zero, and
1186 reduces the need for edit lists for some cases such as video tracks with
1187 B-frames. Additionally, eases conformance with the DASH-IF interoperability
1193 Smooth Streaming content can be pushed in real time to a publishing
1194 point on IIS with this muxer. Example:
1196 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
1199 @subsection Audible AAX
1201 Audible AAX files are encrypted M4B files, and they can be decrypted by specifying a 4 byte activation secret.
1203 ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
1208 The MP3 muxer writes a raw MP3 stream with the following optional features:
1211 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
1212 2.4 are supported, the @code{id3v2_version} private option controls which one is
1213 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
1216 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
1217 The pictures are supplied to the muxer in form of a video stream with a single
1218 packet. There can be any number of those streams, each will correspond to a
1219 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
1220 to APIC @var{description} and @var{picture type} respectively. See
1221 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
1223 Note that the APIC frames must be written at the beginning, so the muxer will
1224 buffer the audio frames until it gets all the pictures. It is therefore advised
1225 to provide the pictures as soon as possible to avoid excessive buffering.
1228 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
1229 default, but will be written only if the output is seekable. The
1230 @code{write_xing} private option can be used to disable it. The frame contains
1231 various information that may be useful to the decoder, like the audio duration
1235 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1236 enabled with the @code{write_id3v1} private option, but as its capabilities are
1237 very limited, its usage is not recommended.
1242 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1244 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1247 To attach a picture to an mp3 file select both the audio and the picture stream
1250 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1251 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1254 Write a "clean" MP3 without any extra features:
1256 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1261 MPEG transport stream muxer.
1263 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1265 The recognized metadata settings in mpegts muxer are @code{service_provider}
1266 and @code{service_name}. If they are not set the default for
1267 @code{service_provider} is @samp{FFmpeg} and the default for
1268 @code{service_name} is @samp{Service01}.
1272 The muxer options are:
1275 @item mpegts_transport_stream_id @var{integer}
1276 Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
1277 Default is @code{0x0001}.
1279 @item mpegts_original_network_id @var{integer}
1280 Set the @samp{original_network_id}. This is unique identifier of a
1281 network in DVB. Its main use is in the unique identification of a service
1282 through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
1285 @item mpegts_service_id @var{integer}
1286 Set the @samp{service_id}, also known as program in DVB. Default is
1289 @item mpegts_service_type @var{integer}
1290 Set the program @samp{service_type}. Default is @code{digital_tv}.
1291 Accepts the following options:
1294 Any hexdecimal value between @code{0x01} to @code{0xff} as defined in
1299 Digital Radio service.
1302 @item advanced_codec_digital_radio
1303 Advanced Codec Digital Radio service.
1304 @item mpeg2_digital_hdtv
1305 MPEG2 Digital HDTV service.
1306 @item advanced_codec_digital_sdtv
1307 Advanced Codec Digital SDTV service.
1308 @item advanced_codec_digital_hdtv
1309 Advanced Codec Digital HDTV service.
1312 @item mpegts_pmt_start_pid @var{integer}
1313 Set the first PID for PMT. Default is @code{0x1000}. Max is @code{0x1f00}.
1315 @item mpegts_start_pid @var{integer}
1316 Set the first PID for data packets. Default is @code{0x0100}. Max is
1319 @item mpegts_m2ts_mode @var{boolean}
1320 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
1323 @item muxrate @var{integer}
1324 Set a constant muxrate. Default is VBR.
1326 @item pes_payload_size @var{integer}
1327 Set minimum PES packet payload in bytes. Default is @code{2930}.
1329 @item mpegts_flags @var{flags}
1330 Set mpegts flags. Accepts the following options:
1332 @item resend_headers
1333 Reemit PAT/PMT before writing the next packet.
1335 Use LATM packetization for AAC.
1336 @item pat_pmt_at_frames
1337 Reemit PAT and PMT at each video frame.
1339 Conform to System B (DVB) instead of System A (ATSC).
1340 @item initial_discontinuity
1341 Mark the initial packet of each stream as discontinuity.
1344 @item resend_headers @var{integer}
1345 Reemit PAT/PMT before writing the next packet. This option is deprecated:
1346 use @option{mpegts_flags} instead.
1348 @item mpegts_copyts @var{boolean}
1349 Preserve original timestamps, if value is set to @code{1}. Default value
1350 is @code{-1}, which results in shifting timestamps so that they start from 0.
1352 @item omit_video_pes_length @var{boolean}
1353 Omit the PES packet length for video packets. Default is @code{1} (true).
1355 @item pcr_period @var{integer}
1356 Override the default PCR retransmission time in milliseconds. Ignored if
1357 variable muxrate is selected. Default is @code{20}.
1359 @item pat_period @var{double}
1360 Maximum time in seconds between PAT/PMT tables.
1362 @item sdt_period @var{double}
1363 Maximum time in seconds between SDT tables.
1365 @item tables_version @var{integer}
1366 Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
1367 This option allows updating stream structure so that standard consumer may
1368 detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
1369 usage) or restart @command{ffmpeg} instance, cyclically changing
1370 @option{tables_version} value:
1373 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1374 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1376 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1377 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1378 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1386 ffmpeg -i file.mpg -c copy \
1387 -mpegts_original_network_id 0x1122 \
1388 -mpegts_transport_stream_id 0x3344 \
1389 -mpegts_service_id 0x5566 \
1390 -mpegts_pmt_start_pid 0x1500 \
1391 -mpegts_start_pid 0x150 \
1392 -metadata service_provider="Some provider" \
1393 -metadata service_name="Some Channel" \
1397 @section mxf, mxf_d10
1403 The muxer options are:
1406 @item store_user_comments @var{bool}
1407 Set if user comments should be stored if available or never.
1408 IRT D-10 does not allow user comments. The default is thus to write them for
1409 mxf but not for mxf_d10
1416 This muxer does not generate any output file, it is mainly useful for
1417 testing or benchmarking purposes.
1419 For example to benchmark decoding with @command{ffmpeg} you can use the
1422 ffmpeg -benchmark -i INPUT -f null out.null
1425 Note that the above command does not read or write the @file{out.null}
1426 file, but specifying the output file is required by the @command{ffmpeg}
1429 Alternatively you can write the command as:
1431 ffmpeg -benchmark -i INPUT -f null -
1437 @item -syncpoints @var{flags}
1438 Change the syncpoint usage in nut:
1440 @item @var{default} use the normal low-overhead seeking aids.
1441 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1442 Use of this option is not recommended, as the resulting files are very damage
1443 sensitive and seeking is not possible. Also in general the overhead from
1444 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1445 all growing data tables, allowing to mux endless streams with limited memory
1446 and without these disadvantages.
1447 @item @var{timestamped} extend the syncpoint with a wallclock field.
1449 The @var{none} and @var{timestamped} flags are experimental.
1450 @item -write_index @var{bool}
1451 Write index at the end, the default is to write an index.
1455 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1460 Ogg container muxer.
1463 @item -page_duration @var{duration}
1464 Preferred page duration, in microseconds. The muxer will attempt to create
1465 pages that are approximately @var{duration} microseconds long. This allows the
1466 user to compromise between seek granularity and container overhead. The default
1467 is 1 second. A value of 0 will fill all segments, making pages as large as
1468 possible. A value of 1 will effectively use 1 packet-per-page in most
1469 situations, giving a small seek granularity at the cost of additional container
1471 @item -serial_offset @var{value}
1472 Serial value from which to set the streams serial number.
1473 Setting it to different and sufficiently large values ensures that the produced
1474 ogg files can be safely chained.
1479 @section segment, stream_segment, ssegment
1481 Basic stream segmenter.
1483 This muxer outputs streams to a number of separate files of nearly
1484 fixed duration. Output filename pattern can be set in a fashion
1485 similar to @ref{image2}, or by using a @code{strftime} template if
1486 the @option{strftime} option is enabled.
1488 @code{stream_segment} is a variant of the muxer used to write to
1489 streaming output formats, i.e. which do not require global headers,
1490 and is recommended for outputting e.g. to MPEG transport stream segments.
1491 @code{ssegment} is a shorter alias for @code{stream_segment}.
1493 Every segment starts with a keyframe of the selected reference stream,
1494 which is set through the @option{reference_stream} option.
1496 Note that if you want accurate splitting for a video file, you need to
1497 make the input key frames correspond to the exact splitting times
1498 expected by the segmenter, or the segment muxer will start the new
1499 segment with the key frame found next after the specified start
1502 The segment muxer works best with a single constant frame rate video.
1504 Optionally it can generate a list of the created segments, by setting
1505 the option @var{segment_list}. The list type is specified by the
1506 @var{segment_list_type} option. The entry filenames in the segment
1507 list are set by default to the basename of the corresponding segment
1510 See also the @ref{hls} muxer, which provides a more specific
1511 implementation for HLS segmentation.
1515 The segment muxer supports the following options:
1518 @item increment_tc @var{1|0}
1519 if set to @code{1}, increment timecode between each segment
1520 If this is selected, the input need to have
1521 a timecode in the first video stream. Default value is
1524 @item reference_stream @var{specifier}
1525 Set the reference stream, as specified by the string @var{specifier}.
1526 If @var{specifier} is set to @code{auto}, the reference is chosen
1527 automatically. Otherwise it must be a stream specifier (see the ``Stream
1528 specifiers'' chapter in the ffmpeg manual) which specifies the
1529 reference stream. The default value is @code{auto}.
1531 @item segment_format @var{format}
1532 Override the inner container format, by default it is guessed by the filename
1535 @item segment_format_options @var{options_list}
1536 Set output format options using a :-separated list of key=value
1537 parameters. Values containing the @code{:} special character must be
1540 @item segment_list @var{name}
1541 Generate also a listfile named @var{name}. If not specified no
1542 listfile is generated.
1544 @item segment_list_flags @var{flags}
1545 Set flags affecting the segment list generation.
1547 It currently supports the following flags:
1550 Allow caching (only affects M3U8 list files).
1553 Allow live-friendly file generation.
1556 @item segment_list_size @var{size}
1557 Update the list file so that it contains at most @var{size}
1558 segments. If 0 the list file will contain all the segments. Default
1561 @item segment_list_entry_prefix @var{prefix}
1562 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1563 By default no prefix is applied.
1565 @item segment_list_type @var{type}
1566 Select the listing format.
1568 The following values are recognized:
1571 Generate a flat list for the created segments, one segment per line.
1574 Generate a list for the created segments, one segment per line,
1575 each line matching the format (comma-separated values):
1577 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1580 @var{segment_filename} is the name of the output file generated by the
1581 muxer according to the provided pattern. CSV escaping (according to
1582 RFC4180) is applied if required.
1584 @var{segment_start_time} and @var{segment_end_time} specify
1585 the segment start and end time expressed in seconds.
1587 A list file with the suffix @code{".csv"} or @code{".ext"} will
1588 auto-select this format.
1590 @samp{ext} is deprecated in favor or @samp{csv}.
1593 Generate an ffconcat file for the created segments. The resulting file
1594 can be read using the FFmpeg @ref{concat} demuxer.
1596 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1597 auto-select this format.
1600 Generate an extended M3U8 file, version 3, compliant with
1601 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1603 A list file with the suffix @code{".m3u8"} will auto-select this format.
1606 If not specified the type is guessed from the list file name suffix.
1608 @item segment_time @var{time}
1609 Set segment duration to @var{time}, the value must be a duration
1610 specification. Default value is "2". See also the
1611 @option{segment_times} option.
1613 Note that splitting may not be accurate, unless you force the
1614 reference stream key-frames at the given time. See the introductory
1615 notice and the examples below.
1617 @item segment_atclocktime @var{1|0}
1618 If set to "1" split at regular clock time intervals starting from 00:00
1619 o'clock. The @var{time} value specified in @option{segment_time} is
1620 used for setting the length of the splitting interval.
1622 For example with @option{segment_time} set to "900" this makes it possible
1623 to create files at 12:00 o'clock, 12:15, 12:30, etc.
1625 Default value is "0".
1627 @item segment_clocktime_offset @var{duration}
1628 Delay the segment splitting times with the specified duration when using
1629 @option{segment_atclocktime}.
1631 For example with @option{segment_time} set to "900" and
1632 @option{segment_clocktime_offset} set to "300" this makes it possible to
1633 create files at 12:05, 12:20, 12:35, etc.
1635 Default value is "0".
1637 @item segment_clocktime_wrap_duration @var{duration}
1638 Force the segmenter to only start a new segment if a packet reaches the muxer
1639 within the specified duration after the segmenting clock time. This way you
1640 can make the segmenter more resilient to backward local time jumps, such as
1641 leap seconds or transition to standard time from daylight savings time.
1643 Default is the maximum possible duration which means starting a new segment
1644 regardless of the elapsed time since the last clock time.
1646 @item segment_time_delta @var{delta}
1647 Specify the accuracy time when selecting the start time for a
1648 segment, expressed as a duration specification. Default value is "0".
1650 When delta is specified a key-frame will start a new segment if its
1651 PTS satisfies the relation:
1653 PTS >= start_time - time_delta
1656 This option is useful when splitting video content, which is always
1657 split at GOP boundaries, in case a key frame is found just before the
1658 specified split time.
1660 In particular may be used in combination with the @file{ffmpeg} option
1661 @var{force_key_frames}. The key frame times specified by
1662 @var{force_key_frames} may not be set accurately because of rounding
1663 issues, with the consequence that a key frame time may result set just
1664 before the specified time. For constant frame rate videos a value of
1665 1/(2*@var{frame_rate}) should address the worst case mismatch between
1666 the specified time and the time set by @var{force_key_frames}.
1668 @item segment_times @var{times}
1669 Specify a list of split points. @var{times} contains a list of comma
1670 separated duration specifications, in increasing order. See also
1671 the @option{segment_time} option.
1673 @item segment_frames @var{frames}
1674 Specify a list of split video frame numbers. @var{frames} contains a
1675 list of comma separated integer numbers, in increasing order.
1677 This option specifies to start a new segment whenever a reference
1678 stream key frame is found and the sequential number (starting from 0)
1679 of the frame is greater or equal to the next value in the list.
1681 @item segment_wrap @var{limit}
1682 Wrap around segment index once it reaches @var{limit}.
1684 @item segment_start_number @var{number}
1685 Set the sequence number of the first segment. Defaults to @code{0}.
1687 @item strftime @var{1|0}
1688 Use the @code{strftime} function to define the name of the new
1689 segments to write. If this is selected, the output segment name must
1690 contain a @code{strftime} function template. Default value is
1693 @item break_non_keyframes @var{1|0}
1694 If enabled, allow segments to start on frames other than keyframes. This
1695 improves behavior on some players when the time between keyframes is
1696 inconsistent, but may make things worse on others, and can cause some oddities
1697 during seeking. Defaults to @code{0}.
1699 @item reset_timestamps @var{1|0}
1700 Reset timestamps at the beginning of each segment, so that each segment
1701 will start with near-zero timestamps. It is meant to ease the playback
1702 of the generated segments. May not work with some combinations of
1703 muxers/codecs. It is set to @code{0} by default.
1705 @item initial_offset @var{offset}
1706 Specify timestamp offset to apply to the output packet timestamps. The
1707 argument must be a time duration specification, and defaults to 0.
1709 @item write_empty_segments @var{1|0}
1710 If enabled, write an empty segment if there are no packets during the period a
1711 segment would usually span. Otherwise, the segment will be filled with the next
1712 packet written. Defaults to @code{0}.
1715 Make sure to require a closed GOP when encoding and to set the GOP
1716 size to fit your segment time constraint.
1718 @subsection Examples
1722 Remux the content of file @file{in.mkv} to a list of segments
1723 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
1724 generated segments to @file{out.list}:
1726 ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
1730 Segment input and set output format options for the output segments:
1732 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
1736 Segment the input file according to the split points specified by the
1737 @var{segment_times} option:
1739 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
1743 Use the @command{ffmpeg} @option{force_key_frames}
1744 option to force key frames in the input at the specified location, together
1745 with the segment option @option{segment_time_delta} to account for
1746 possible roundings operated when setting key frame times.
1748 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
1749 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
1751 In order to force key frames on the input file, transcoding is
1755 Segment the input file by splitting the input file according to the
1756 frame numbers sequence specified with the @option{segment_frames} option:
1758 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
1762 Convert the @file{in.mkv} to TS segments using the @code{libx264}
1763 and @code{aac} encoders:
1765 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
1769 Segment the input file, and create an M3U8 live playlist (can be used
1770 as live HLS source):
1772 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
1773 -segment_list_flags +live -segment_time 10 out%03d.mkv
1777 @section smoothstreaming
1779 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
1783 Specify the number of fragments kept in the manifest. Default 0 (keep all).
1785 @item extra_window_size
1786 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
1788 @item lookahead_count
1789 Specify the number of lookahead fragments. Default 2.
1791 @item min_frag_duration
1792 Specify the minimum fragment duration (in microseconds). Default 5000000.
1794 @item remove_at_exit
1795 Specify whether to remove all fragments when finished. Default 0 (do not remove).
1802 The fifo pseudo-muxer allows the separation of encoding and muxing by using
1803 first-in-first-out queue and running the actual muxer in a separate thread. This
1804 is especially useful in combination with the @ref{tee} muxer and can be used to
1805 send data to several destinations with different reliability/writing speed/latency.
1807 API users should be aware that callback functions (interrupt_callback,
1808 io_open and io_close) used within its AVFormatContext must be thread-safe.
1810 The behavior of the fifo muxer if the queue fills up or if the output fails is
1816 output can be transparently restarted with configurable delay between retries
1817 based on real time or time of the processed stream.
1820 encoding can be blocked during temporary failure, or continue transparently
1821 dropping packets in case fifo queue fills up.
1828 Specify the format name. Useful if it cannot be guessed from the
1832 Specify size of the queue (number of packets). Default value is 60.
1835 Specify format options for the underlying muxer. Muxer options can be specified
1836 as a list of @var{key}=@var{value} pairs separated by ':'.
1838 @item drop_pkts_on_overflow @var{bool}
1839 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
1840 rather than blocking the encoder. This makes it possible to continue streaming without
1841 delaying the input, at the cost of omitting part of the stream. By default
1842 this option is set to 0 (false), so in such cases the encoder will be blocked
1843 until the muxer processes some of the packets and none of them is lost.
1845 @item attempt_recovery @var{bool}
1846 If failure occurs, attempt to recover the output. This is especially useful
1847 when used with network output, since it makes it possible to restart streaming transparently.
1848 By default this option is set to 0 (false).
1850 @item max_recovery_attempts
1851 Sets maximum number of successive unsuccessful recovery attempts after which
1852 the output fails permanently. By default this option is set to 0 (unlimited).
1854 @item recovery_wait_time @var{duration}
1855 Waiting time before the next recovery attempt after previous unsuccessful
1856 recovery attempt. Default value is 5 seconds.
1858 @item recovery_wait_streamtime @var{bool}
1859 If set to 0 (false), the real time is used when waiting for the recovery
1860 attempt (i.e. the recovery will be attempted after at least
1861 recovery_wait_time seconds).
1862 If set to 1 (true), the time of the processed stream is taken into account
1863 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
1864 seconds of the stream is omitted).
1865 By default, this option is set to 0 (false).
1867 @item recover_any_error @var{bool}
1868 If set to 1 (true), recovery will be attempted regardless of type of the error
1869 causing the failure. By default this option is set to 0 (false) and in case of
1870 certain (usually permanent) errors the recovery is not attempted even when
1871 @var{attempt_recovery} is set to 1.
1873 @item restart_with_keyframe @var{bool}
1874 Specify whether to wait for the keyframe after recovering from
1875 queue overflow or failure. This option is set to 0 (false) by default.
1879 @subsection Examples
1884 Stream something to rtmp server, continue processing the stream at real-time
1885 rate even in case of temporary failure (network outage) and attempt to recover
1886 streaming every second indefinitely.
1888 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
1889 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
1897 The tee muxer can be used to write the same data to several files or any
1898 other kind of muxer. It can be used, for example, to both stream a video to
1899 the network and save it to disk at the same time.
1901 It is different from specifying several outputs to the @command{ffmpeg}
1902 command-line tool because the audio and video data will be encoded only once
1903 with the tee muxer; encoding can be a very expensive process. It is not
1904 useful when using the libavformat API directly because it is then possible
1905 to feed the same packets to several muxers directly.
1909 @item use_fifo @var{bool}
1910 If set to 1, slave outputs will be processed in separate thread using @ref{fifo}
1911 muxer. This allows to compensate for different speed/latency/reliability of
1912 outputs and setup transparent recovery. By default this feature is turned off.
1915 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
1919 The slave outputs are specified in the file name given to the muxer,
1920 separated by '|'. If any of the slave name contains the '|' separator,
1921 leading or trailing spaces or any special character, it must be
1922 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
1923 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
1925 Muxer options can be specified for each slave by prepending them as a list of
1926 @var{key}=@var{value} pairs separated by ':', between square brackets. If
1927 the options values contain a special character or the ':' separator, they
1928 must be escaped; note that this is a second level escaping.
1930 The following special options are also recognized:
1933 Specify the format name. Useful if it cannot be guessed from the
1936 @item bsfs[/@var{spec}]
1937 Specify a list of bitstream filters to apply to the specified
1940 @item use_fifo @var{bool}
1941 This allows to override tee muxer use_fifo option for individual slave muxer.
1944 This allows to override tee muxer fifo_options for individual slave muxer.
1947 It is possible to specify to which streams a given bitstream filter
1948 applies, by appending a stream specifier to the option separated by
1949 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
1950 stream specifiers}). If the stream specifier is not specified, the
1951 bitstream filters will be applied to all streams in the output.
1953 Several bitstream filters can be specified, separated by ",".
1956 Select the streams that should be mapped to the slave output,
1957 specified by a stream specifier. If not specified, this defaults to
1958 all the input streams. You may use multiple stream specifiers
1959 separated by commas (@code{,}) e.g.: @code{a:0,v}
1962 Specify behaviour on output failure. This can be set to either @code{abort} (which is
1963 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
1964 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
1965 will continue without being affected.
1968 @subsection Examples
1972 Encode something and both archive it in a WebM file and stream it
1973 as MPEG-TS over UDP (the streams need to be explicitly mapped):
1975 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
1976 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
1980 As above, but continue streaming even if output to local file fails
1981 (for example local drive fills up):
1983 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
1984 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
1988 Use @command{ffmpeg} to encode the input, and send the output
1989 to three different destinations. The @code{dump_extra} bitstream
1990 filter is used to add extradata information to all the output video
1991 keyframes packets, as requested by the MPEG-TS format. The select
1992 option is applied to @file{out.aac} in order to make it contain only
1995 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
1996 -f tee "[bsfs/v=dump_extra]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
2000 As below, but select only stream @code{a:1} for the audio output. Note
2001 that a second level escaping must be performed, as ":" is a special
2002 character used to separate options.
2004 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2005 -f tee "[bsfs/v=dump_extra]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
2009 Note: some codecs may need different options depending on the output format;
2010 the auto-detection of this can not work with the tee muxer. The main example
2011 is the @option{global_header} flag.
2013 @section webm_dash_manifest
2015 WebM DASH Manifest muxer.
2017 This muxer implements the WebM DASH Manifest specification to generate the DASH
2018 manifest XML. It also supports manifest generation for DASH live streams.
2020 For more information see:
2024 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
2026 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
2031 This muxer supports the following options:
2034 @item adaptation_sets
2035 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
2036 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
2037 audio and video streams. Any number of adaptation sets can be added using this option.
2040 Set this to 1 to create a live stream DASH Manifest. Default: 0.
2042 @item chunk_start_index
2043 Start index of the first chunk. This will go in the @samp{startNumber} attribute
2044 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
2046 @item chunk_duration_ms
2047 Duration of each chunk in milliseconds. This will go in the @samp{duration}
2048 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
2050 @item utc_timing_url
2051 URL of the page that will return the UTC timestamp in ISO format. This will go
2052 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
2055 @item time_shift_buffer_depth
2056 Smallest time (in seconds) shifting buffer for which any Representation is
2057 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
2058 attribute of the @samp{MPD} element. Default: 60.
2060 @item minimum_update_period
2061 Minimum update period (in seconds) of the manifest. This will go in the
2062 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
2068 ffmpeg -f webm_dash_manifest -i video1.webm \
2069 -f webm_dash_manifest -i video2.webm \
2070 -f webm_dash_manifest -i audio1.webm \
2071 -f webm_dash_manifest -i audio2.webm \
2072 -map 0 -map 1 -map 2 -map 3 \
2074 -f webm_dash_manifest \
2075 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
2081 WebM Live Chunk Muxer.
2083 This muxer writes out WebM headers and chunks as separate files which can be
2084 consumed by clients that support WebM Live streams via DASH.
2088 This muxer supports the following options:
2091 @item chunk_start_index
2092 Index of the first chunk (defaults to 0).
2095 Filename of the header where the initialization data will be written.
2097 @item audio_chunk_duration
2098 Duration of each audio chunk in milliseconds (defaults to 5000).
2103 ffmpeg -f v4l2 -i /dev/video0 \
2107 -s 640x360 -keyint_min 30 -g 30 \
2109 -header webm_live_video_360.hdr \
2110 -chunk_start_index 1 \
2111 webm_live_video_360_%d.chk \
2116 -header webm_live_audio_128.hdr \
2117 -chunk_start_index 1 \
2118 -audio_chunk_duration 1000 \
2119 webm_live_audio_128_%d.chk