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 -http_user_agent @var{user_agent}
251 Override User-Agent field in HTTP header. Applicable only for HTTP output.
252 @item -hls_playlist @var{hls_playlist}
253 Generate HLS playlist files as well. The master playlist is generated with the filename master.m3u8.
254 One media playlist file is generated for each stream with filenames media_0.m3u8, media_1.m3u8, etc.
255 @item -adaptation_sets @var{adaptation_sets}
256 Assign streams to AdaptationSets. Syntax is "id=x,streams=a,b,c id=y,streams=d,e" with x and y being the IDs
257 of the adaptation sets and a,b,c,d and e are the indices of the mapped streams.
259 To map all video (or audio) streams to an AdaptationSet, "v" (or "a") can be used as stream identifier instead of IDs.
261 When no assignment is defined, this defaults to an AdaptationSet for each stream.
267 Per-packet CRC (Cyclic Redundancy Check) testing format.
269 This muxer computes and prints the Adler-32 CRC for each audio
270 and video packet. By default audio frames are converted to signed
271 16-bit raw audio and video frames to raw video before computing the
274 The output of the muxer consists of a line for each audio and video
277 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
280 @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
285 For example to compute the CRC of the audio and video frames in
286 @file{INPUT}, converted to raw audio and video packets, and store it
287 in the file @file{out.crc}:
289 ffmpeg -i INPUT -f framecrc out.crc
292 To print the information to stdout, use the command:
294 ffmpeg -i INPUT -f framecrc -
297 With @command{ffmpeg}, you can select the output format to which the
298 audio and video frames are encoded before computing the CRC for each
299 packet by specifying the audio and video codec. For example, to
300 compute the CRC of each decoded input audio frame converted to PCM
301 unsigned 8-bit and of each decoded input video frame converted to
302 MPEG-2 video, use the command:
304 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
307 See also the @ref{crc} muxer.
312 Per-packet hash testing format.
314 This muxer computes and prints a cryptographic hash for each audio
315 and video packet. This can be used for packet-by-packet equality
316 checks without having to individually do a binary comparison on each.
318 By default audio frames are converted to signed 16-bit raw audio and
319 video frames to raw video before computing the hash, but the output
320 of explicit conversions to other codecs can also be used. It uses the
321 SHA-256 cryptographic hash function by default, but supports several
324 The output of the muxer consists of a line for each audio and video
327 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
330 @var{hash} is a hexadecimal number representing the computed hash
334 @item hash @var{algorithm}
335 Use the cryptographic hash function specified by the string @var{algorithm}.
336 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
337 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
338 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
339 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
345 To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
346 converted to raw audio and video packets, and store it in the file
349 ffmpeg -i INPUT -f framehash out.sha256
352 To print the information to stdout, using the MD5 hash function, use
355 ffmpeg -i INPUT -f framehash -hash md5 -
358 See also the @ref{hash} muxer.
363 Per-packet MD5 testing format.
365 This is a variant of the @ref{framehash} muxer. Unlike that muxer,
366 it defaults to using the MD5 hash function.
370 To compute the MD5 hash of the audio and video frames in @file{INPUT},
371 converted to raw audio and video packets, and store it in the file
374 ffmpeg -i INPUT -f framemd5 out.md5
377 To print the information to stdout, use the command:
379 ffmpeg -i INPUT -f framemd5 -
382 See also the @ref{framehash} and @ref{md5} muxers.
389 It accepts the following options:
393 Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
394 for looping indefinitely (default).
397 Force the delay (expressed in centiseconds) after the last frame. Each frame
398 ends with a delay until the next frame. The default is @code{-1}, which is a
399 special value to tell the muxer to re-use the previous delay. In case of a
400 loop, you might want to customize this value to mark a pause for instance.
403 For example, to encode a gif looping 10 times, with a 5 seconds delay between
406 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
409 Note 1: if you wish to extract the frames into separate GIF files, you need to
410 force the @ref{image2} muxer:
412 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
415 Note 2: the GIF format has a very large time base: the delay between two frames
416 can therefore not be smaller than one centi second.
423 This muxer computes and prints a cryptographic hash of all the input
424 audio and video frames. This can be used for equality checks without
425 having to do a complete binary comparison.
427 By default audio frames are converted to signed 16-bit raw audio and
428 video frames to raw video before computing the hash, but the output
429 of explicit conversions to other codecs can also be used. Timestamps
430 are ignored. It uses the SHA-256 cryptographic hash function by default,
431 but supports several other algorithms.
433 The output of the muxer consists of a single line of the form:
434 @var{algo}=@var{hash}, where @var{algo} is a short string representing
435 the hash function used, and @var{hash} is a hexadecimal number
436 representing the computed hash.
439 @item hash @var{algorithm}
440 Use the cryptographic hash function specified by the string @var{algorithm}.
441 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
442 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
443 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
444 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
450 To compute the SHA-256 hash of the input converted to raw audio and
451 video, and store it in the file @file{out.sha256}:
453 ffmpeg -i INPUT -f hash out.sha256
456 To print an MD5 hash to stdout use the command:
458 ffmpeg -i INPUT -f hash -hash md5 -
461 See also the @ref{framehash} muxer.
466 Apple HTTP Live Streaming muxer that segments MPEG-TS according to
467 the HTTP Live Streaming (HLS) specification.
469 It creates a playlist file, and one or more segment files. The output filename
470 specifies the playlist filename.
472 By default, the muxer creates a file for each segment produced. These files
473 have the same name as the playlist, followed by a sequential number and a
476 Make sure to require a closed GOP when encoding and to set the GOP
477 size to fit your segment time constraint.
479 For example, to convert an input file with @command{ffmpeg}:
481 ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
483 This example will produce the playlist, @file{out.m3u8}, and segment files:
484 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
486 See also the @ref{segment} muxer, which provides a more generic and
487 flexible implementation of a segmenter, and can be used to perform HLS
492 This muxer supports the following options:
495 @item hls_init_time @var{seconds}
496 Set the initial target segment length in seconds. Default value is @var{0}.
497 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
498 After the initial playlist is filled @command{ffmpeg} will cut segments
499 at duration equal to @code{hls_time}
501 @item hls_time @var{seconds}
502 Set the target segment length in seconds. Default value is 2.
503 Segment will be cut on the next key frame after this time has passed.
505 @item hls_list_size @var{size}
506 Set the maximum number of playlist entries. If set to 0 the list file
507 will contain all the segments. Default value is 5.
509 @item hls_ts_options @var{options_list}
510 Set output format options using a :-separated list of key=value
511 parameters. Values containing @code{:} special characters must be
514 @item hls_wrap @var{wrap}
515 This is a deprecated option, you can use @code{hls_list_size}
516 and @code{hls_flags delete_segments} instead it
518 This option is useful to avoid to fill the disk with many segment
519 files, and limits the maximum number of segment files written to disk
523 @item hls_start_number_source
524 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
525 Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
526 segment and subtitle filenames. In any case, if @code{hls_flags append_list}
527 is set and read playlist sequence number is greater than the specified start sequence number,
528 then that value will be used as start value.
530 It accepts the following values:
534 @item generic (default)
535 Set the starting sequence numbers according to @var{start_number} option value.
538 The start number will be the seconds since epoch (1970-01-01 00:00:00)
541 The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
545 @item start_number @var{number}
546 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
547 when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
548 Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
551 @item hls_allow_cache @var{allowcache}
552 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
554 @item hls_base_url @var{baseurl}
555 Append @var{baseurl} to every entry in the playlist.
556 Useful to generate playlists with absolute paths.
558 Note that the playlist sequence number must be unique for each segment
559 and it is not to be confused with the segment filename sequence number
560 which can be cyclic, for example if the @option{wrap} option is
563 @item hls_segment_filename @var{filename}
564 Set the segment filename. Unless @code{hls_flags single_file} is set,
565 @var{filename} is used as a string format with the segment number:
567 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
569 This example will produce the playlist, @file{out.m3u8}, and segment files:
570 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
572 @var{filename} may contain full path or relative path specification,
573 but only the file name part without any path info will be contained in the m3u8 segment list.
574 Should a relative path be specified, the path of the created segment
575 files will be relative to the current working directory.
576 When use_localtime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
580 Use strftime() on @var{filename} to expand the segment filename with localtime.
581 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
582 hls_flag and %%d will be the specifier.
584 ffmpeg -i in.nut -use_localtime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
586 This example will produce the playlist, @file{out.m3u8}, and segment files:
587 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
588 Note: On some systems/environments, the @code{%s} specifier is not available. See
589 @code{strftime()} documentation.
591 ffmpeg -i in.nut -use_localtime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
593 This example will produce the playlist, @file{out.m3u8}, and segment files:
594 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
596 @item use_localtime_mkdir
597 Used together with -use_localtime, it will create all subdirectories which
598 is expanded in @var{filename}.
600 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
602 This example will create a directory 201560215 (if it does not exist), and then
603 produce the playlist, @file{out.m3u8}, and segment files:
604 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
607 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
609 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
610 produce the playlist, @file{out.m3u8}, and segment files:
611 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
614 @item hls_key_info_file @var{key_info_file}
615 Use the information in @var{key_info_file} for segment encryption. The first
616 line of @var{key_info_file} specifies the key URI written to the playlist. The
617 key URL is used to access the encryption key during playback. The second line
618 specifies the path to the key file used to obtain the key during the encryption
619 process. The key file is read as a single packed array of 16 octets in binary
620 format. The optional third line specifies the initialization vector (IV) as a
621 hexadecimal string to be used instead of the segment sequence number (default)
622 for encryption. Changes to @var{key_info_file} will result in segment
623 encryption with the new key/IV and an entry in the playlist for the new key
624 URI/IV if @code{hls_flags periodic_rekey} is enabled.
626 Key info file format:
635 http://server/file.key
640 Example key file paths:
648 0123456789ABCDEF0123456789ABCDEF
651 Key info file example:
653 http://server/file.key
655 0123456789ABCDEF0123456789ABCDEF
658 Example shell script:
662 openssl rand 16 > file.key
663 echo $BASE_URL/file.key > file.keyinfo
664 echo file.key >> file.keyinfo
665 echo $(openssl rand -hex 16) >> file.keyinfo
666 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
667 -hls_key_info_file file.keyinfo out.m3u8
670 @item -hls_enc @var{enc}
671 Enable (1) or disable (0) the AES128 encryption.
672 When enabled every segment generated is encrypted and the encryption key
673 is saved as @var{playlist name}.key.
675 @item -hls_enc_key @var{key}
676 Hex-coded 16byte key to encrypt the segments, by default it
677 is randomly generated.
679 @item -hls_enc_key_url @var{keyurl}
680 If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
683 @item -hls_enc_iv @var{iv}
684 Hex-coded 16byte initialization vector for every segment instead
685 of the autogenerated ones.
687 @item hls_segment_type @var{flags}
692 If this flag is set, the hls segment files will format to mpegts.
693 the mpegts files is used in all hls versions.
696 If this flag is set, the hls segment files will format to fragment mp4 looks like dash.
697 the fmp4 files is used in hls after version 7.
701 @item hls_fmp4_init_filename @var{filename}
702 set filename to the fragment files header file, default filename is @file{init.mp4}.
704 @item hls_flags @var{flags}
709 If this flag is set, the muxer will store all segments in a single MPEG-TS
710 file, and will use byte ranges in the playlist. HLS playlists generated with
711 this way will have the version number 4.
714 ffmpeg -i in.nut -hls_flags single_file out.m3u8
716 Will produce the playlist, @file{out.m3u8}, and a single segment file,
719 @item delete_segments
720 Segment files removed from the playlist are deleted after a period of time
721 equal to the duration of the segment plus the duration of the playlist.
724 Append new segments into the end of old segment list,
725 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
727 @item round_durations
728 Round the duration info in the playlist file segment info to integer
729 values, instead of using floating point.
732 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
733 first segment's information.
736 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
739 The file specified by @code{hls_key_info_file} will be checked periodically and
740 detect updates to the encryption info. Be sure to replace this file atomically,
741 including the file containing the AES encryption key.
743 @item independent_segments
744 Add the @code{#EXT-X-INDEPENDENT-SEGMENTS} to playlists that has video segments
745 and when all the segments of that playlist are guaranteed to start with a Key frame.
748 Allow segments to start on frames other than keyframes. This improves
749 behavior on some players when the time between keyframes is inconsistent,
750 but may make things worse on others, and can cause some oddities during
751 seeking. This flag should be used with the @code{hls_time} option.
753 @item program_date_time
754 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
756 @item second_level_segment_index
757 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
758 besides date/time values when use_localtime is on.
759 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
761 @item second_level_segment_size
762 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
763 expression besides date/time values when use_localtime is on.
764 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
766 @item second_level_segment_duration
767 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
768 expression besides date/time values when use_localtime is on.
769 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
772 ffmpeg -i sample.mpeg \
773 -f hls -hls_time 3 -hls_list_size 5 \
774 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
775 -use_localtime 1 -use_localtime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
777 This will produce segments like this:
778 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
781 Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
782 serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
783 before they have been added to the m3u8 playlist.
787 @item hls_playlist_type event
788 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
789 @option{hls_list_size} to 0; the playlist can only be appended to.
791 @item hls_playlist_type vod
792 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
793 @option{hls_list_size} to 0; the playlist must not change.
796 Use the given HTTP method to create the hls files.
798 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
800 This example will upload all the mpegts segment files to the HTTP
801 server using the HTTP PUT method, and update the m3u8 files every
802 @code{refresh} times using the same method.
803 Note that the HTTP server must support the given method for uploading
806 @item http_user_agent
807 Override User-Agent field in HTTP header. Applicable only for HTTP output.
810 Map string which specifies how to group the audio, video and subtitle streams
811 into different variant streams. The variant stream groups are separated
813 Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
814 the keys to specify audio, video and subtitle streams respectively.
815 Allowed values are 0 to 9 (limited just based on practical usage).
818 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
819 -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" \
820 http://example.com/live/out.m3u8
822 This example creates two hls variant streams. The first variant stream will
823 contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
824 second variant stream will contain video stream of bitrate 256k and audio
825 stream of bitrate 32k. Here, two media playlist with file names out_1.m3u8 and
826 out_2.m3u8 will be created.
828 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
829 -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
830 http://example.com/live/out.m3u8
832 This example creates three hls variant streams. The first variant stream will
833 be a video only stream with video bitrate 1000k, the second variant stream will
834 be an audio only stream with bitrate 64k and the third variant stream will be a
835 video only stream with bitrate 256k. Here, three media playlist with file names
836 out_1.m3u8, out_2.m3u8 and out_3.m3u8 will be created.
838 By default, a single hls variant containing all the encoded streams is created.
841 Create HLS master playlist with the given name.
844 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
846 This example creates HLS master playlist with name master.m3u8 and it is
847 published at http://example.com/live/
849 @item master_pl_publish_rate
850 Publish master play list repeatedly every after specified number of segment intervals.
853 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
854 -hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
857 This example creates HLS master playlist with name master.m3u8 and keep
858 publishing it repeatedly every after 30 segments i.e. every after 60s.
860 @item http_persistent
861 Use persistent HTTP connections. Applicable only for HTTP output.
870 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
874 Size cannot exceed 256 pixels in any dimension
877 Only BMP and PNG images can be stored
880 If a BMP image is used, it must be one of the following pixel formats:
882 BMP Bit Depth FFmpeg Pixel Format
892 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
895 If a PNG image is used, it must use the rgba pixel format
903 The image file muxer writes video frames to image files.
905 The output filenames are specified by a pattern, which can be used to
906 produce sequentially numbered series of files.
907 The pattern may contain the string "%d" or "%0@var{N}d", this string
908 specifies the position of the characters representing a numbering in
909 the filenames. If the form "%0@var{N}d" is used, the string
910 representing the number in each filename is 0-padded to @var{N}
911 digits. The literal character '%' can be specified in the pattern with
914 If the pattern contains "%d" or "%0@var{N}d", the first filename of
915 the file list specified will contain the number 1, all the following
916 numbers will be sequential.
918 The pattern may contain a suffix which is used to automatically
919 determine the format of the image files to write.
921 For example the pattern "img-%03d.bmp" will specify a sequence of
922 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
923 @file{img-010.bmp}, etc.
924 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
925 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
930 The following example shows how to use @command{ffmpeg} for creating a
931 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
932 taking one image every second from the input video:
934 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
937 Note that with @command{ffmpeg}, if the format is not specified with the
938 @code{-f} option and the output filename specifies an image file
939 format, the image2 muxer is automatically selected, so the previous
940 command can be written as:
942 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
945 Note also that the pattern must not necessarily contain "%d" or
946 "%0@var{N}d", for example to create a single image file
947 @file{img.jpeg} from the start of the input video you can employ the command:
949 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
952 The @option{strftime} option allows you to expand the filename with
953 date and time information. Check the documentation of
954 the @code{strftime()} function for the syntax.
956 For example to generate image files from the @code{strftime()}
957 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
960 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
963 You can set the file name with current frame's PTS:
965 ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
972 If set to 1, expand the filename with pts from pkt->pts.
976 Start the sequence from the specified number. Default value is 1.
979 If set to 1, the filename will always be interpreted as just a
980 filename, not a pattern, and the corresponding file will be continuously
981 overwritten with new images. Default value is 0.
984 If set to 1, expand the filename with date and time information from
985 @code{strftime()}. Default value is 0.
988 The image muxer supports the .Y.U.V image file format. This format is
989 special in that that each image frame consists of three files, for
990 each of the YUV420P components. To read or write this image file format,
991 specify the name of the '.Y' file. The muxer will automatically open the
992 '.U' and '.V' files as required.
996 Matroska container muxer.
998 This muxer implements the matroska and webm container specs.
1000 @subsection Metadata
1002 The recognized metadata settings in this muxer are:
1006 Set title name provided to a single track.
1009 Specify the language of the track in the Matroska languages form.
1011 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
1012 639-2/B) form (like "fre" for French), or a language code mixed with a
1013 country code for specialities in languages (like "fre-ca" for Canadian
1017 Set stereo 3D video layout of two views in a single video track.
1019 The following values are recognized:
1024 Both views are arranged side by side, Left-eye view is on the left
1026 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
1028 Both views are arranged in top-bottom orientation, Left-eye view is on top
1029 @item checkerboard_rl
1030 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
1031 @item checkerboard_lr
1032 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
1033 @item row_interleaved_rl
1034 Each view is constituted by a row based interleaving, Right-eye view is first row
1035 @item row_interleaved_lr
1036 Each view is constituted by a row based interleaving, Left-eye view is first row
1037 @item col_interleaved_rl
1038 Both views are arranged in a column based interleaving manner, Right-eye view is first column
1039 @item col_interleaved_lr
1040 Both views are arranged in a column based interleaving manner, Left-eye view is first column
1041 @item anaglyph_cyan_red
1042 All frames are in anaglyph format viewable through red-cyan filters
1044 Both views are arranged side by side, Right-eye view is on the left
1045 @item anaglyph_green_magenta
1046 All frames are in anaglyph format viewable through green-magenta filters
1048 Both eyes laced in one Block, Left-eye view is first
1050 Both eyes laced in one Block, Right-eye view is first
1054 For example a 3D WebM clip can be created using the following command line:
1056 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
1061 This muxer supports the following options:
1064 @item reserve_index_space
1065 By default, this muxer writes the index for seeking (called cues in Matroska
1066 terms) at the end of the file, because it cannot know in advance how much space
1067 to leave for the index at the beginning of the file. However for some use cases
1068 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
1069 index at the beginning of the file.
1071 If this option is set to a non-zero value, the muxer will reserve a given amount
1072 of space in the file header and then try to write the cues there when the muxing
1073 finishes. If the available space does not suffice, muxing will fail. A safe size
1074 for most use cases should be about 50kB per hour of video.
1076 Note that cues are only written if the output is seekable and this option will
1077 have no effect if it is not.
1085 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
1086 defaults to using the MD5 hash function.
1088 @subsection Examples
1090 To compute the MD5 hash of the input converted to raw
1091 audio and video, and store it in the file @file{out.md5}:
1093 ffmpeg -i INPUT -f md5 out.md5
1096 You can print the MD5 to stdout with the command:
1098 ffmpeg -i INPUT -f md5 -
1101 See also the @ref{hash} and @ref{framemd5} muxers.
1103 @section mov, mp4, ismv
1105 MOV/MP4/ISMV (Smooth Streaming) muxer.
1107 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
1108 file has all the metadata about all packets stored in one location
1109 (written at the end of the file, it can be moved to the start for
1110 better playback by adding @var{faststart} to the @var{movflags}, or
1111 using the @command{qt-faststart} tool). A fragmented
1112 file consists of a number of fragments, where packets and metadata
1113 about these packets are stored together. Writing a fragmented
1114 file has the advantage that the file is decodable even if the
1115 writing is interrupted (while a normal MOV/MP4 is undecodable if
1116 it is not properly finished), and it requires less memory when writing
1117 very long files (since writing normal MOV/MP4 files stores info about
1118 every single packet in memory until the file is closed). The downside
1119 is that it is less compatible with other applications.
1123 Fragmentation is enabled by setting one of the AVOptions that define
1124 how to cut the file into fragments:
1127 @item -moov_size @var{bytes}
1128 Reserves space for the moov atom at the beginning of the file instead of placing the
1129 moov atom at the end. If the space reserved is insufficient, muxing will fail.
1130 @item -movflags frag_keyframe
1131 Start a new fragment at each video keyframe.
1132 @item -frag_duration @var{duration}
1133 Create fragments that are @var{duration} microseconds long.
1134 @item -frag_size @var{size}
1135 Create fragments that contain up to @var{size} bytes of payload data.
1136 @item -movflags frag_custom
1137 Allow the caller to manually choose when to cut fragments, by
1138 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
1139 the packets written so far. (This is only useful with other
1140 applications integrating libavformat, not from @command{ffmpeg}.)
1141 @item -min_frag_duration @var{duration}
1142 Don't create fragments that are shorter than @var{duration} microseconds long.
1145 If more than one condition is specified, fragments are cut when
1146 one of the specified conditions is fulfilled. The exception to this is
1147 @code{-min_frag_duration}, which has to be fulfilled for any of the other
1148 conditions to apply.
1150 Additionally, the way the output file is written can be adjusted
1151 through a few other options:
1154 @item -movflags empty_moov
1155 Write an initial moov atom directly at the start of the file, without
1156 describing any samples in it. Generally, an mdat/moov pair is written
1157 at the start of the file, as a normal MOV/MP4 file, containing only
1158 a short portion of the file. With this option set, there is no initial
1159 mdat atom, and the moov atom only describes the tracks but has
1162 This option is implicitly set when writing ismv (Smooth Streaming) files.
1163 @item -movflags separate_moof
1164 Write a separate moof (movie fragment) atom for each track. Normally,
1165 packets for all tracks are written in a moof atom (which is slightly
1166 more efficient), but with this option set, the muxer writes one moof/mdat
1167 pair for each track, making it easier to separate tracks.
1169 This option is implicitly set when writing ismv (Smooth Streaming) files.
1170 @item -movflags faststart
1171 Run a second pass moving the index (moov atom) to the beginning of the file.
1172 This operation can take a while, and will not work in various situations such
1173 as fragmented output, thus it is not enabled by default.
1174 @item -movflags rtphint
1175 Add RTP hinting tracks to the output file.
1176 @item -movflags disable_chpl
1177 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
1178 and a QuickTime chapter track are written to the file. With this option
1179 set, only the QuickTime chapter track will be written. Nero chapters can
1180 cause failures when the file is reprocessed with certain tagging programs, like
1181 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
1182 @item -movflags omit_tfhd_offset
1183 Do not write any absolute base_data_offset in tfhd atoms. This avoids
1184 tying fragments to absolute byte positions in the file/streams.
1185 @item -movflags default_base_moof
1186 Similarly to the omit_tfhd_offset, this flag avoids writing the
1187 absolute base_data_offset field in tfhd atoms, but does so by using
1188 the new default-base-is-moof flag instead. This flag is new from
1189 14496-12:2012. This may make the fragments easier to parse in certain
1190 circumstances (avoiding basing track fragment location calculations
1191 on the implicit end of the previous track fragment).
1193 Specify @code{on} to force writing a timecode track, @code{off} to disable it
1194 and @code{auto} to write a timecode track only for mov and mp4 output (default).
1195 @item -movflags negative_cts_offsets
1196 Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
1197 be negative. This enables the initial sample to have DTS/CTS of zero, and
1198 reduces the need for edit lists for some cases such as video tracks with
1199 B-frames. Additionally, eases conformance with the DASH-IF interoperability
1205 Smooth Streaming content can be pushed in real time to a publishing
1206 point on IIS with this muxer. Example:
1208 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
1211 @subsection Audible AAX
1213 Audible AAX files are encrypted M4B files, and they can be decrypted by specifying a 4 byte activation secret.
1215 ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
1220 The MP3 muxer writes a raw MP3 stream with the following optional features:
1223 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
1224 2.4 are supported, the @code{id3v2_version} private option controls which one is
1225 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
1228 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
1229 The pictures are supplied to the muxer in form of a video stream with a single
1230 packet. There can be any number of those streams, each will correspond to a
1231 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
1232 to APIC @var{description} and @var{picture type} respectively. See
1233 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
1235 Note that the APIC frames must be written at the beginning, so the muxer will
1236 buffer the audio frames until it gets all the pictures. It is therefore advised
1237 to provide the pictures as soon as possible to avoid excessive buffering.
1240 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
1241 default, but will be written only if the output is seekable. The
1242 @code{write_xing} private option can be used to disable it. The frame contains
1243 various information that may be useful to the decoder, like the audio duration
1247 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1248 enabled with the @code{write_id3v1} private option, but as its capabilities are
1249 very limited, its usage is not recommended.
1254 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1256 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1259 To attach a picture to an mp3 file select both the audio and the picture stream
1262 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1263 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1266 Write a "clean" MP3 without any extra features:
1268 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1273 MPEG transport stream muxer.
1275 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1277 The recognized metadata settings in mpegts muxer are @code{service_provider}
1278 and @code{service_name}. If they are not set the default for
1279 @code{service_provider} is @samp{FFmpeg} and the default for
1280 @code{service_name} is @samp{Service01}.
1284 The muxer options are:
1287 @item mpegts_transport_stream_id @var{integer}
1288 Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
1289 Default is @code{0x0001}.
1291 @item mpegts_original_network_id @var{integer}
1292 Set the @samp{original_network_id}. This is unique identifier of a
1293 network in DVB. Its main use is in the unique identification of a service
1294 through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
1297 @item mpegts_service_id @var{integer}
1298 Set the @samp{service_id}, also known as program in DVB. Default is
1301 @item mpegts_service_type @var{integer}
1302 Set the program @samp{service_type}. Default is @code{digital_tv}.
1303 Accepts the following options:
1306 Any hexdecimal value between @code{0x01} to @code{0xff} as defined in
1311 Digital Radio service.
1314 @item advanced_codec_digital_radio
1315 Advanced Codec Digital Radio service.
1316 @item mpeg2_digital_hdtv
1317 MPEG2 Digital HDTV service.
1318 @item advanced_codec_digital_sdtv
1319 Advanced Codec Digital SDTV service.
1320 @item advanced_codec_digital_hdtv
1321 Advanced Codec Digital HDTV service.
1324 @item mpegts_pmt_start_pid @var{integer}
1325 Set the first PID for PMT. Default is @code{0x1000}. Max is @code{0x1f00}.
1327 @item mpegts_start_pid @var{integer}
1328 Set the first PID for data packets. Default is @code{0x0100}. Max is
1331 @item mpegts_m2ts_mode @var{boolean}
1332 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
1335 @item muxrate @var{integer}
1336 Set a constant muxrate. Default is VBR.
1338 @item pes_payload_size @var{integer}
1339 Set minimum PES packet payload in bytes. Default is @code{2930}.
1341 @item mpegts_flags @var{flags}
1342 Set mpegts flags. Accepts the following options:
1344 @item resend_headers
1345 Reemit PAT/PMT before writing the next packet.
1347 Use LATM packetization for AAC.
1348 @item pat_pmt_at_frames
1349 Reemit PAT and PMT at each video frame.
1351 Conform to System B (DVB) instead of System A (ATSC).
1352 @item initial_discontinuity
1353 Mark the initial packet of each stream as discontinuity.
1356 @item resend_headers @var{integer}
1357 Reemit PAT/PMT before writing the next packet. This option is deprecated:
1358 use @option{mpegts_flags} instead.
1360 @item mpegts_copyts @var{boolean}
1361 Preserve original timestamps, if value is set to @code{1}. Default value
1362 is @code{-1}, which results in shifting timestamps so that they start from 0.
1364 @item omit_video_pes_length @var{boolean}
1365 Omit the PES packet length for video packets. Default is @code{1} (true).
1367 @item pcr_period @var{integer}
1368 Override the default PCR retransmission time in milliseconds. Ignored if
1369 variable muxrate is selected. Default is @code{20}.
1371 @item pat_period @var{double}
1372 Maximum time in seconds between PAT/PMT tables.
1374 @item sdt_period @var{double}
1375 Maximum time in seconds between SDT tables.
1377 @item tables_version @var{integer}
1378 Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
1379 This option allows updating stream structure so that standard consumer may
1380 detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
1381 usage) or restart @command{ffmpeg} instance, cyclically changing
1382 @option{tables_version} value:
1385 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1386 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1388 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1389 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1390 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1398 ffmpeg -i file.mpg -c copy \
1399 -mpegts_original_network_id 0x1122 \
1400 -mpegts_transport_stream_id 0x3344 \
1401 -mpegts_service_id 0x5566 \
1402 -mpegts_pmt_start_pid 0x1500 \
1403 -mpegts_start_pid 0x150 \
1404 -metadata service_provider="Some provider" \
1405 -metadata service_name="Some Channel" \
1409 @section mxf, mxf_d10
1415 The muxer options are:
1418 @item store_user_comments @var{bool}
1419 Set if user comments should be stored if available or never.
1420 IRT D-10 does not allow user comments. The default is thus to write them for
1421 mxf but not for mxf_d10
1428 This muxer does not generate any output file, it is mainly useful for
1429 testing or benchmarking purposes.
1431 For example to benchmark decoding with @command{ffmpeg} you can use the
1434 ffmpeg -benchmark -i INPUT -f null out.null
1437 Note that the above command does not read or write the @file{out.null}
1438 file, but specifying the output file is required by the @command{ffmpeg}
1441 Alternatively you can write the command as:
1443 ffmpeg -benchmark -i INPUT -f null -
1449 @item -syncpoints @var{flags}
1450 Change the syncpoint usage in nut:
1452 @item @var{default} use the normal low-overhead seeking aids.
1453 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1454 Use of this option is not recommended, as the resulting files are very damage
1455 sensitive and seeking is not possible. Also in general the overhead from
1456 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1457 all growing data tables, allowing to mux endless streams with limited memory
1458 and without these disadvantages.
1459 @item @var{timestamped} extend the syncpoint with a wallclock field.
1461 The @var{none} and @var{timestamped} flags are experimental.
1462 @item -write_index @var{bool}
1463 Write index at the end, the default is to write an index.
1467 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1472 Ogg container muxer.
1475 @item -page_duration @var{duration}
1476 Preferred page duration, in microseconds. The muxer will attempt to create
1477 pages that are approximately @var{duration} microseconds long. This allows the
1478 user to compromise between seek granularity and container overhead. The default
1479 is 1 second. A value of 0 will fill all segments, making pages as large as
1480 possible. A value of 1 will effectively use 1 packet-per-page in most
1481 situations, giving a small seek granularity at the cost of additional container
1483 @item -serial_offset @var{value}
1484 Serial value from which to set the streams serial number.
1485 Setting it to different and sufficiently large values ensures that the produced
1486 ogg files can be safely chained.
1491 @section segment, stream_segment, ssegment
1493 Basic stream segmenter.
1495 This muxer outputs streams to a number of separate files of nearly
1496 fixed duration. Output filename pattern can be set in a fashion
1497 similar to @ref{image2}, or by using a @code{strftime} template if
1498 the @option{strftime} option is enabled.
1500 @code{stream_segment} is a variant of the muxer used to write to
1501 streaming output formats, i.e. which do not require global headers,
1502 and is recommended for outputting e.g. to MPEG transport stream segments.
1503 @code{ssegment} is a shorter alias for @code{stream_segment}.
1505 Every segment starts with a keyframe of the selected reference stream,
1506 which is set through the @option{reference_stream} option.
1508 Note that if you want accurate splitting for a video file, you need to
1509 make the input key frames correspond to the exact splitting times
1510 expected by the segmenter, or the segment muxer will start the new
1511 segment with the key frame found next after the specified start
1514 The segment muxer works best with a single constant frame rate video.
1516 Optionally it can generate a list of the created segments, by setting
1517 the option @var{segment_list}. The list type is specified by the
1518 @var{segment_list_type} option. The entry filenames in the segment
1519 list are set by default to the basename of the corresponding segment
1522 See also the @ref{hls} muxer, which provides a more specific
1523 implementation for HLS segmentation.
1527 The segment muxer supports the following options:
1530 @item increment_tc @var{1|0}
1531 if set to @code{1}, increment timecode between each segment
1532 If this is selected, the input need to have
1533 a timecode in the first video stream. Default value is
1536 @item reference_stream @var{specifier}
1537 Set the reference stream, as specified by the string @var{specifier}.
1538 If @var{specifier} is set to @code{auto}, the reference is chosen
1539 automatically. Otherwise it must be a stream specifier (see the ``Stream
1540 specifiers'' chapter in the ffmpeg manual) which specifies the
1541 reference stream. The default value is @code{auto}.
1543 @item segment_format @var{format}
1544 Override the inner container format, by default it is guessed by the filename
1547 @item segment_format_options @var{options_list}
1548 Set output format options using a :-separated list of key=value
1549 parameters. Values containing the @code{:} special character must be
1552 @item segment_list @var{name}
1553 Generate also a listfile named @var{name}. If not specified no
1554 listfile is generated.
1556 @item segment_list_flags @var{flags}
1557 Set flags affecting the segment list generation.
1559 It currently supports the following flags:
1562 Allow caching (only affects M3U8 list files).
1565 Allow live-friendly file generation.
1568 @item segment_list_size @var{size}
1569 Update the list file so that it contains at most @var{size}
1570 segments. If 0 the list file will contain all the segments. Default
1573 @item segment_list_entry_prefix @var{prefix}
1574 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1575 By default no prefix is applied.
1577 @item segment_list_type @var{type}
1578 Select the listing format.
1580 The following values are recognized:
1583 Generate a flat list for the created segments, one segment per line.
1586 Generate a list for the created segments, one segment per line,
1587 each line matching the format (comma-separated values):
1589 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1592 @var{segment_filename} is the name of the output file generated by the
1593 muxer according to the provided pattern. CSV escaping (according to
1594 RFC4180) is applied if required.
1596 @var{segment_start_time} and @var{segment_end_time} specify
1597 the segment start and end time expressed in seconds.
1599 A list file with the suffix @code{".csv"} or @code{".ext"} will
1600 auto-select this format.
1602 @samp{ext} is deprecated in favor or @samp{csv}.
1605 Generate an ffconcat file for the created segments. The resulting file
1606 can be read using the FFmpeg @ref{concat} demuxer.
1608 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1609 auto-select this format.
1612 Generate an extended M3U8 file, version 3, compliant with
1613 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1615 A list file with the suffix @code{".m3u8"} will auto-select this format.
1618 If not specified the type is guessed from the list file name suffix.
1620 @item segment_time @var{time}
1621 Set segment duration to @var{time}, the value must be a duration
1622 specification. Default value is "2". See also the
1623 @option{segment_times} option.
1625 Note that splitting may not be accurate, unless you force the
1626 reference stream key-frames at the given time. See the introductory
1627 notice and the examples below.
1629 @item segment_atclocktime @var{1|0}
1630 If set to "1" split at regular clock time intervals starting from 00:00
1631 o'clock. The @var{time} value specified in @option{segment_time} is
1632 used for setting the length of the splitting interval.
1634 For example with @option{segment_time} set to "900" this makes it possible
1635 to create files at 12:00 o'clock, 12:15, 12:30, etc.
1637 Default value is "0".
1639 @item segment_clocktime_offset @var{duration}
1640 Delay the segment splitting times with the specified duration when using
1641 @option{segment_atclocktime}.
1643 For example with @option{segment_time} set to "900" and
1644 @option{segment_clocktime_offset} set to "300" this makes it possible to
1645 create files at 12:05, 12:20, 12:35, etc.
1647 Default value is "0".
1649 @item segment_clocktime_wrap_duration @var{duration}
1650 Force the segmenter to only start a new segment if a packet reaches the muxer
1651 within the specified duration after the segmenting clock time. This way you
1652 can make the segmenter more resilient to backward local time jumps, such as
1653 leap seconds or transition to standard time from daylight savings time.
1655 Default is the maximum possible duration which means starting a new segment
1656 regardless of the elapsed time since the last clock time.
1658 @item segment_time_delta @var{delta}
1659 Specify the accuracy time when selecting the start time for a
1660 segment, expressed as a duration specification. Default value is "0".
1662 When delta is specified a key-frame will start a new segment if its
1663 PTS satisfies the relation:
1665 PTS >= start_time - time_delta
1668 This option is useful when splitting video content, which is always
1669 split at GOP boundaries, in case a key frame is found just before the
1670 specified split time.
1672 In particular may be used in combination with the @file{ffmpeg} option
1673 @var{force_key_frames}. The key frame times specified by
1674 @var{force_key_frames} may not be set accurately because of rounding
1675 issues, with the consequence that a key frame time may result set just
1676 before the specified time. For constant frame rate videos a value of
1677 1/(2*@var{frame_rate}) should address the worst case mismatch between
1678 the specified time and the time set by @var{force_key_frames}.
1680 @item segment_times @var{times}
1681 Specify a list of split points. @var{times} contains a list of comma
1682 separated duration specifications, in increasing order. See also
1683 the @option{segment_time} option.
1685 @item segment_frames @var{frames}
1686 Specify a list of split video frame numbers. @var{frames} contains a
1687 list of comma separated integer numbers, in increasing order.
1689 This option specifies to start a new segment whenever a reference
1690 stream key frame is found and the sequential number (starting from 0)
1691 of the frame is greater or equal to the next value in the list.
1693 @item segment_wrap @var{limit}
1694 Wrap around segment index once it reaches @var{limit}.
1696 @item segment_start_number @var{number}
1697 Set the sequence number of the first segment. Defaults to @code{0}.
1699 @item strftime @var{1|0}
1700 Use the @code{strftime} function to define the name of the new
1701 segments to write. If this is selected, the output segment name must
1702 contain a @code{strftime} function template. Default value is
1705 @item break_non_keyframes @var{1|0}
1706 If enabled, allow segments to start on frames other than keyframes. This
1707 improves behavior on some players when the time between keyframes is
1708 inconsistent, but may make things worse on others, and can cause some oddities
1709 during seeking. Defaults to @code{0}.
1711 @item reset_timestamps @var{1|0}
1712 Reset timestamps at the beginning of each segment, so that each segment
1713 will start with near-zero timestamps. It is meant to ease the playback
1714 of the generated segments. May not work with some combinations of
1715 muxers/codecs. It is set to @code{0} by default.
1717 @item initial_offset @var{offset}
1718 Specify timestamp offset to apply to the output packet timestamps. The
1719 argument must be a time duration specification, and defaults to 0.
1721 @item write_empty_segments @var{1|0}
1722 If enabled, write an empty segment if there are no packets during the period a
1723 segment would usually span. Otherwise, the segment will be filled with the next
1724 packet written. Defaults to @code{0}.
1727 Make sure to require a closed GOP when encoding and to set the GOP
1728 size to fit your segment time constraint.
1730 @subsection Examples
1734 Remux the content of file @file{in.mkv} to a list of segments
1735 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
1736 generated segments to @file{out.list}:
1738 ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
1742 Segment input and set output format options for the output segments:
1744 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
1748 Segment the input file according to the split points specified by the
1749 @var{segment_times} option:
1751 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
1755 Use the @command{ffmpeg} @option{force_key_frames}
1756 option to force key frames in the input at the specified location, together
1757 with the segment option @option{segment_time_delta} to account for
1758 possible roundings operated when setting key frame times.
1760 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
1761 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
1763 In order to force key frames on the input file, transcoding is
1767 Segment the input file by splitting the input file according to the
1768 frame numbers sequence specified with the @option{segment_frames} option:
1770 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
1774 Convert the @file{in.mkv} to TS segments using the @code{libx264}
1775 and @code{aac} encoders:
1777 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
1781 Segment the input file, and create an M3U8 live playlist (can be used
1782 as live HLS source):
1784 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
1785 -segment_list_flags +live -segment_time 10 out%03d.mkv
1789 @section smoothstreaming
1791 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
1795 Specify the number of fragments kept in the manifest. Default 0 (keep all).
1797 @item extra_window_size
1798 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
1800 @item lookahead_count
1801 Specify the number of lookahead fragments. Default 2.
1803 @item min_frag_duration
1804 Specify the minimum fragment duration (in microseconds). Default 5000000.
1806 @item remove_at_exit
1807 Specify whether to remove all fragments when finished. Default 0 (do not remove).
1814 The fifo pseudo-muxer allows the separation of encoding and muxing by using
1815 first-in-first-out queue and running the actual muxer in a separate thread. This
1816 is especially useful in combination with the @ref{tee} muxer and can be used to
1817 send data to several destinations with different reliability/writing speed/latency.
1819 API users should be aware that callback functions (interrupt_callback,
1820 io_open and io_close) used within its AVFormatContext must be thread-safe.
1822 The behavior of the fifo muxer if the queue fills up or if the output fails is
1828 output can be transparently restarted with configurable delay between retries
1829 based on real time or time of the processed stream.
1832 encoding can be blocked during temporary failure, or continue transparently
1833 dropping packets in case fifo queue fills up.
1840 Specify the format name. Useful if it cannot be guessed from the
1844 Specify size of the queue (number of packets). Default value is 60.
1847 Specify format options for the underlying muxer. Muxer options can be specified
1848 as a list of @var{key}=@var{value} pairs separated by ':'.
1850 @item drop_pkts_on_overflow @var{bool}
1851 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
1852 rather than blocking the encoder. This makes it possible to continue streaming without
1853 delaying the input, at the cost of omitting part of the stream. By default
1854 this option is set to 0 (false), so in such cases the encoder will be blocked
1855 until the muxer processes some of the packets and none of them is lost.
1857 @item attempt_recovery @var{bool}
1858 If failure occurs, attempt to recover the output. This is especially useful
1859 when used with network output, since it makes it possible to restart streaming transparently.
1860 By default this option is set to 0 (false).
1862 @item max_recovery_attempts
1863 Sets maximum number of successive unsuccessful recovery attempts after which
1864 the output fails permanently. By default this option is set to 0 (unlimited).
1866 @item recovery_wait_time @var{duration}
1867 Waiting time before the next recovery attempt after previous unsuccessful
1868 recovery attempt. Default value is 5 seconds.
1870 @item recovery_wait_streamtime @var{bool}
1871 If set to 0 (false), the real time is used when waiting for the recovery
1872 attempt (i.e. the recovery will be attempted after at least
1873 recovery_wait_time seconds).
1874 If set to 1 (true), the time of the processed stream is taken into account
1875 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
1876 seconds of the stream is omitted).
1877 By default, this option is set to 0 (false).
1879 @item recover_any_error @var{bool}
1880 If set to 1 (true), recovery will be attempted regardless of type of the error
1881 causing the failure. By default this option is set to 0 (false) and in case of
1882 certain (usually permanent) errors the recovery is not attempted even when
1883 @var{attempt_recovery} is set to 1.
1885 @item restart_with_keyframe @var{bool}
1886 Specify whether to wait for the keyframe after recovering from
1887 queue overflow or failure. This option is set to 0 (false) by default.
1891 @subsection Examples
1896 Stream something to rtmp server, continue processing the stream at real-time
1897 rate even in case of temporary failure (network outage) and attempt to recover
1898 streaming every second indefinitely.
1900 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
1901 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
1909 The tee muxer can be used to write the same data to several files or any
1910 other kind of muxer. It can be used, for example, to both stream a video to
1911 the network and save it to disk at the same time.
1913 It is different from specifying several outputs to the @command{ffmpeg}
1914 command-line tool because the audio and video data will be encoded only once
1915 with the tee muxer; encoding can be a very expensive process. It is not
1916 useful when using the libavformat API directly because it is then possible
1917 to feed the same packets to several muxers directly.
1921 @item use_fifo @var{bool}
1922 If set to 1, slave outputs will be processed in separate thread using @ref{fifo}
1923 muxer. This allows to compensate for different speed/latency/reliability of
1924 outputs and setup transparent recovery. By default this feature is turned off.
1927 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
1931 The slave outputs are specified in the file name given to the muxer,
1932 separated by '|'. If any of the slave name contains the '|' separator,
1933 leading or trailing spaces or any special character, it must be
1934 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
1935 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
1937 Muxer options can be specified for each slave by prepending them as a list of
1938 @var{key}=@var{value} pairs separated by ':', between square brackets. If
1939 the options values contain a special character or the ':' separator, they
1940 must be escaped; note that this is a second level escaping.
1942 The following special options are also recognized:
1945 Specify the format name. Useful if it cannot be guessed from the
1948 @item bsfs[/@var{spec}]
1949 Specify a list of bitstream filters to apply to the specified
1952 @item use_fifo @var{bool}
1953 This allows to override tee muxer use_fifo option for individual slave muxer.
1956 This allows to override tee muxer fifo_options for individual slave muxer.
1959 It is possible to specify to which streams a given bitstream filter
1960 applies, by appending a stream specifier to the option separated by
1961 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
1962 stream specifiers}). If the stream specifier is not specified, the
1963 bitstream filters will be applied to all streams in the output.
1965 Several bitstream filters can be specified, separated by ",".
1968 Select the streams that should be mapped to the slave output,
1969 specified by a stream specifier. If not specified, this defaults to
1970 all the input streams. You may use multiple stream specifiers
1971 separated by commas (@code{,}) e.g.: @code{a:0,v}
1974 Specify behaviour on output failure. This can be set to either @code{abort} (which is
1975 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
1976 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
1977 will continue without being affected.
1980 @subsection Examples
1984 Encode something and both archive it in a WebM file and stream it
1985 as MPEG-TS over UDP (the streams need to be explicitly mapped):
1987 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
1988 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
1992 As above, but continue streaming even if output to local file fails
1993 (for example local drive fills up):
1995 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
1996 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2000 Use @command{ffmpeg} to encode the input, and send the output
2001 to three different destinations. The @code{dump_extra} bitstream
2002 filter is used to add extradata information to all the output video
2003 keyframes packets, as requested by the MPEG-TS format. The select
2004 option is applied to @file{out.aac} in order to make it contain only
2007 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2008 -f tee "[bsfs/v=dump_extra]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
2012 As below, but select only stream @code{a:1} for the audio output. Note
2013 that a second level escaping must be performed, as ":" is a special
2014 character used to separate options.
2016 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2017 -f tee "[bsfs/v=dump_extra]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
2021 Note: some codecs may need different options depending on the output format;
2022 the auto-detection of this can not work with the tee muxer. The main example
2023 is the @option{global_header} flag.
2025 @section webm_dash_manifest
2027 WebM DASH Manifest muxer.
2029 This muxer implements the WebM DASH Manifest specification to generate the DASH
2030 manifest XML. It also supports manifest generation for DASH live streams.
2032 For more information see:
2036 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
2038 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
2043 This muxer supports the following options:
2046 @item adaptation_sets
2047 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
2048 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
2049 audio and video streams. Any number of adaptation sets can be added using this option.
2052 Set this to 1 to create a live stream DASH Manifest. Default: 0.
2054 @item chunk_start_index
2055 Start index of the first chunk. This will go in the @samp{startNumber} attribute
2056 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
2058 @item chunk_duration_ms
2059 Duration of each chunk in milliseconds. This will go in the @samp{duration}
2060 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
2062 @item utc_timing_url
2063 URL of the page that will return the UTC timestamp in ISO format. This will go
2064 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
2067 @item time_shift_buffer_depth
2068 Smallest time (in seconds) shifting buffer for which any Representation is
2069 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
2070 attribute of the @samp{MPD} element. Default: 60.
2072 @item minimum_update_period
2073 Minimum update period (in seconds) of the manifest. This will go in the
2074 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
2080 ffmpeg -f webm_dash_manifest -i video1.webm \
2081 -f webm_dash_manifest -i video2.webm \
2082 -f webm_dash_manifest -i audio1.webm \
2083 -f webm_dash_manifest -i audio2.webm \
2084 -map 0 -map 1 -map 2 -map 3 \
2086 -f webm_dash_manifest \
2087 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
2093 WebM Live Chunk Muxer.
2095 This muxer writes out WebM headers and chunks as separate files which can be
2096 consumed by clients that support WebM Live streams via DASH.
2100 This muxer supports the following options:
2103 @item chunk_start_index
2104 Index of the first chunk (defaults to 0).
2107 Filename of the header where the initialization data will be written.
2109 @item audio_chunk_duration
2110 Duration of each audio chunk in milliseconds (defaults to 5000).
2115 ffmpeg -f v4l2 -i /dev/video0 \
2119 -s 640x360 -keyint_min 30 -g 30 \
2121 -header webm_live_video_360.hdr \
2122 -chunk_start_index 1 \
2123 webm_live_video_360_%d.chk \
2128 -header webm_live_audio_128.hdr \
2129 -chunk_start_index 1 \
2130 -audio_chunk_duration 1000 \
2131 webm_live_audio_128_%d.chk