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 -http_persistent @var{http_persistent}
253 Use persistent HTTP connections. Applicable only for HTTP output.
254 @item -hls_playlist @var{hls_playlist}
255 Generate HLS playlist files as well. The master playlist is generated with the filename master.m3u8.
256 One media playlist file is generated for each stream with filenames media_0.m3u8, media_1.m3u8, etc.
257 @item -adaptation_sets @var{adaptation_sets}
258 Assign streams to AdaptationSets. Syntax is "id=x,streams=a,b,c id=y,streams=d,e" with x and y being the IDs
259 of the adaptation sets and a,b,c,d and e are the indices of the mapped streams.
261 To map all video (or audio) streams to an AdaptationSet, "v" (or "a") can be used as stream identifier instead of IDs.
263 When no assignment is defined, this defaults to an AdaptationSet for each stream.
269 Per-packet CRC (Cyclic Redundancy Check) testing format.
271 This muxer computes and prints the Adler-32 CRC for each audio
272 and video packet. By default audio frames are converted to signed
273 16-bit raw audio and video frames to raw video before computing the
276 The output of the muxer consists of a line for each audio and video
279 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
282 @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
287 For example to compute the CRC of the audio and video frames in
288 @file{INPUT}, converted to raw audio and video packets, and store it
289 in the file @file{out.crc}:
291 ffmpeg -i INPUT -f framecrc out.crc
294 To print the information to stdout, use the command:
296 ffmpeg -i INPUT -f framecrc -
299 With @command{ffmpeg}, you can select the output format to which the
300 audio and video frames are encoded before computing the CRC for each
301 packet by specifying the audio and video codec. For example, to
302 compute the CRC of each decoded input audio frame converted to PCM
303 unsigned 8-bit and of each decoded input video frame converted to
304 MPEG-2 video, use the command:
306 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
309 See also the @ref{crc} muxer.
314 Per-packet hash testing format.
316 This muxer computes and prints a cryptographic hash for each audio
317 and video packet. This can be used for packet-by-packet equality
318 checks without having to individually do a binary comparison on each.
320 By default audio frames are converted to signed 16-bit raw audio and
321 video frames to raw video before computing the hash, but the output
322 of explicit conversions to other codecs can also be used. It uses the
323 SHA-256 cryptographic hash function by default, but supports several
326 The output of the muxer consists of a line for each audio and video
329 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
332 @var{hash} is a hexadecimal number representing the computed hash
336 @item hash @var{algorithm}
337 Use the cryptographic hash function specified by the string @var{algorithm}.
338 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
339 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
340 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
341 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
347 To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
348 converted to raw audio and video packets, and store it in the file
351 ffmpeg -i INPUT -f framehash out.sha256
354 To print the information to stdout, using the MD5 hash function, use
357 ffmpeg -i INPUT -f framehash -hash md5 -
360 See also the @ref{hash} muxer.
365 Per-packet MD5 testing format.
367 This is a variant of the @ref{framehash} muxer. Unlike that muxer,
368 it defaults to using the MD5 hash function.
372 To compute the MD5 hash of the audio and video frames in @file{INPUT},
373 converted to raw audio and video packets, and store it in the file
376 ffmpeg -i INPUT -f framemd5 out.md5
379 To print the information to stdout, use the command:
381 ffmpeg -i INPUT -f framemd5 -
384 See also the @ref{framehash} and @ref{md5} muxers.
391 It accepts the following options:
395 Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
396 for looping indefinitely (default).
399 Force the delay (expressed in centiseconds) after the last frame. Each frame
400 ends with a delay until the next frame. The default is @code{-1}, which is a
401 special value to tell the muxer to re-use the previous delay. In case of a
402 loop, you might want to customize this value to mark a pause for instance.
405 For example, to encode a gif looping 10 times, with a 5 seconds delay between
408 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
411 Note 1: if you wish to extract the frames into separate GIF files, you need to
412 force the @ref{image2} muxer:
414 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
417 Note 2: the GIF format has a very large time base: the delay between two frames
418 can therefore not be smaller than one centi second.
425 This muxer computes and prints a cryptographic hash of all the input
426 audio and video frames. This can be used for equality checks without
427 having to do a complete binary comparison.
429 By default audio frames are converted to signed 16-bit raw audio and
430 video frames to raw video before computing the hash, but the output
431 of explicit conversions to other codecs can also be used. Timestamps
432 are ignored. It uses the SHA-256 cryptographic hash function by default,
433 but supports several other algorithms.
435 The output of the muxer consists of a single line of the form:
436 @var{algo}=@var{hash}, where @var{algo} is a short string representing
437 the hash function used, and @var{hash} is a hexadecimal number
438 representing the computed hash.
441 @item hash @var{algorithm}
442 Use the cryptographic hash function specified by the string @var{algorithm}.
443 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
444 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
445 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
446 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
452 To compute the SHA-256 hash of the input converted to raw audio and
453 video, and store it in the file @file{out.sha256}:
455 ffmpeg -i INPUT -f hash out.sha256
458 To print an MD5 hash to stdout use the command:
460 ffmpeg -i INPUT -f hash -hash md5 -
463 See also the @ref{framehash} muxer.
468 Apple HTTP Live Streaming muxer that segments MPEG-TS according to
469 the HTTP Live Streaming (HLS) specification.
471 It creates a playlist file, and one or more segment files. The output filename
472 specifies the playlist filename.
474 By default, the muxer creates a file for each segment produced. These files
475 have the same name as the playlist, followed by a sequential number and a
478 Make sure to require a closed GOP when encoding and to set the GOP
479 size to fit your segment time constraint.
481 For example, to convert an input file with @command{ffmpeg}:
483 ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
485 This example will produce the playlist, @file{out.m3u8}, and segment files:
486 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
488 See also the @ref{segment} muxer, which provides a more generic and
489 flexible implementation of a segmenter, and can be used to perform HLS
494 This muxer supports the following options:
497 @item hls_init_time @var{seconds}
498 Set the initial target segment length in seconds. Default value is @var{0}.
499 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
500 After the initial playlist is filled @command{ffmpeg} will cut segments
501 at duration equal to @code{hls_time}
503 @item hls_time @var{seconds}
504 Set the target segment length in seconds. Default value is 2.
505 Segment will be cut on the next key frame after this time has passed.
507 @item hls_list_size @var{size}
508 Set the maximum number of playlist entries. If set to 0 the list file
509 will contain all the segments. Default value is 5.
511 @item hls_ts_options @var{options_list}
512 Set output format options using a :-separated list of key=value
513 parameters. Values containing @code{:} special characters must be
516 @item hls_wrap @var{wrap}
517 This is a deprecated option, you can use @code{hls_list_size}
518 and @code{hls_flags delete_segments} instead it
520 This option is useful to avoid to fill the disk with many segment
521 files, and limits the maximum number of segment files written to disk
525 @item hls_start_number_source
526 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
527 Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
528 segment and subtitle filenames. In any case, if @code{hls_flags append_list}
529 is set and read playlist sequence number is greater than the specified start sequence number,
530 then that value will be used as start value.
532 It accepts the following values:
536 @item generic (default)
537 Set the starting sequence numbers according to @var{start_number} option value.
540 The start number will be the seconds since epoch (1970-01-01 00:00:00)
543 The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
547 @item start_number @var{number}
548 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
549 when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
550 Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
553 @item hls_allow_cache @var{allowcache}
554 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
556 @item hls_base_url @var{baseurl}
557 Append @var{baseurl} to every entry in the playlist.
558 Useful to generate playlists with absolute paths.
560 Note that the playlist sequence number must be unique for each segment
561 and it is not to be confused with the segment filename sequence number
562 which can be cyclic, for example if the @option{wrap} option is
565 @item hls_segment_filename @var{filename}
566 Set the segment filename. Unless @code{hls_flags single_file} is set,
567 @var{filename} is used as a string format with the segment number:
569 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
571 This example will produce the playlist, @file{out.m3u8}, and segment files:
572 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
574 @var{filename} may contain full path or relative path specification,
575 but only the file name part without any path info will be contained in the m3u8 segment list.
576 Should a relative path be specified, the path of the created segment
577 files will be relative to the current working directory.
578 When use_localtime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
580 When @code{var_stream_map} is set with two or more variant streams, the
581 @var{filename} pattern must contain the string "%v", this string specifies
582 the position of variant stream index in the generated segment file names.
584 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
585 -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" \
586 -hls_segment_filename 'file_%v_%03d.ts' out_%v.m3u8
588 This example will produce the playlists segment file sets:
589 @file{file_0_000.ts}, @file{file_0_001.ts}, @file{file_0_002.ts}, etc. and
590 @file{file_1_000.ts}, @file{file_1_001.ts}, @file{file_1_002.ts}, etc.
593 Use strftime() on @var{filename} to expand the segment filename with localtime.
594 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
595 hls_flag and %%d will be the specifier.
597 ffmpeg -i in.nut -use_localtime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
599 This example will produce the playlist, @file{out.m3u8}, and segment files:
600 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
601 Note: On some systems/environments, the @code{%s} specifier is not available. See
602 @code{strftime()} documentation.
604 ffmpeg -i in.nut -use_localtime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
606 This example will produce the playlist, @file{out.m3u8}, and segment files:
607 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
609 @item use_localtime_mkdir
610 Used together with -use_localtime, it will create all subdirectories which
611 is expanded in @var{filename}.
613 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
615 This example will create a directory 201560215 (if it does not exist), and then
616 produce the playlist, @file{out.m3u8}, and segment files:
617 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
620 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
622 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
623 produce the playlist, @file{out.m3u8}, and segment files:
624 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
627 @item hls_key_info_file @var{key_info_file}
628 Use the information in @var{key_info_file} for segment encryption. The first
629 line of @var{key_info_file} specifies the key URI written to the playlist. The
630 key URL is used to access the encryption key during playback. The second line
631 specifies the path to the key file used to obtain the key during the encryption
632 process. The key file is read as a single packed array of 16 octets in binary
633 format. The optional third line specifies the initialization vector (IV) as a
634 hexadecimal string to be used instead of the segment sequence number (default)
635 for encryption. Changes to @var{key_info_file} will result in segment
636 encryption with the new key/IV and an entry in the playlist for the new key
637 URI/IV if @code{hls_flags periodic_rekey} is enabled.
639 Key info file format:
648 http://server/file.key
653 Example key file paths:
661 0123456789ABCDEF0123456789ABCDEF
664 Key info file example:
666 http://server/file.key
668 0123456789ABCDEF0123456789ABCDEF
671 Example shell script:
675 openssl rand 16 > file.key
676 echo $BASE_URL/file.key > file.keyinfo
677 echo file.key >> file.keyinfo
678 echo $(openssl rand -hex 16) >> file.keyinfo
679 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
680 -hls_key_info_file file.keyinfo out.m3u8
683 @item -hls_enc @var{enc}
684 Enable (1) or disable (0) the AES128 encryption.
685 When enabled every segment generated is encrypted and the encryption key
686 is saved as @var{playlist name}.key.
688 @item -hls_enc_key @var{key}
689 Hex-coded 16byte key to encrypt the segments, by default it
690 is randomly generated.
692 @item -hls_enc_key_url @var{keyurl}
693 If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
696 @item -hls_enc_iv @var{iv}
697 Hex-coded 16byte initialization vector for every segment instead
698 of the autogenerated ones.
700 @item hls_segment_type @var{flags}
705 If this flag is set, the hls segment files will format to mpegts.
706 the mpegts files is used in all hls versions.
709 If this flag is set, the hls segment files will format to fragment mp4 looks like dash.
710 the fmp4 files is used in hls after version 7.
714 @item hls_fmp4_init_filename @var{filename}
715 set filename to the fragment files header file, default filename is @file{init.mp4}.
717 When @code{var_stream_map} is set with two or more variant streams, the
718 @var{filename} pattern must contain the string "%v", this string specifies
719 the position of variant stream index in the generated init file names.
721 @item hls_flags @var{flags}
726 If this flag is set, the muxer will store all segments in a single MPEG-TS
727 file, and will use byte ranges in the playlist. HLS playlists generated with
728 this way will have the version number 4.
731 ffmpeg -i in.nut -hls_flags single_file out.m3u8
733 Will produce the playlist, @file{out.m3u8}, and a single segment file,
736 @item delete_segments
737 Segment files removed from the playlist are deleted after a period of time
738 equal to the duration of the segment plus the duration of the playlist.
741 Append new segments into the end of old segment list,
742 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
744 @item round_durations
745 Round the duration info in the playlist file segment info to integer
746 values, instead of using floating point.
749 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
750 first segment's information.
753 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
756 The file specified by @code{hls_key_info_file} will be checked periodically and
757 detect updates to the encryption info. Be sure to replace this file atomically,
758 including the file containing the AES encryption key.
760 @item independent_segments
761 Add the @code{#EXT-X-INDEPENDENT-SEGMENTS} to playlists that has video segments
762 and when all the segments of that playlist are guaranteed to start with a Key frame.
765 Allow segments to start on frames other than keyframes. This improves
766 behavior on some players when the time between keyframes is inconsistent,
767 but may make things worse on others, and can cause some oddities during
768 seeking. This flag should be used with the @code{hls_time} option.
770 @item program_date_time
771 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
773 @item second_level_segment_index
774 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
775 besides date/time values when use_localtime is on.
776 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
778 @item second_level_segment_size
779 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
780 expression besides date/time values when use_localtime is on.
781 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
783 @item second_level_segment_duration
784 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
785 expression besides date/time values when use_localtime is on.
786 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
789 ffmpeg -i sample.mpeg \
790 -f hls -hls_time 3 -hls_list_size 5 \
791 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
792 -use_localtime 1 -use_localtime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
794 This will produce segments like this:
795 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
798 Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
799 serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
800 before they have been added to the m3u8 playlist.
804 @item hls_playlist_type event
805 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
806 @option{hls_list_size} to 0; the playlist can only be appended to.
808 @item hls_playlist_type vod
809 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
810 @option{hls_list_size} to 0; the playlist must not change.
813 Use the given HTTP method to create the hls files.
815 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
817 This example will upload all the mpegts segment files to the HTTP
818 server using the HTTP PUT method, and update the m3u8 files every
819 @code{refresh} times using the same method.
820 Note that the HTTP server must support the given method for uploading
823 @item http_user_agent
824 Override User-Agent field in HTTP header. Applicable only for HTTP output.
827 Map string which specifies how to group the audio, video and subtitle streams
828 into different variant streams. The variant stream groups are separated
830 Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
831 the keys to specify audio, video and subtitle streams respectively.
832 Allowed values are 0 to 9 (limited just based on practical usage).
834 When there are two or more variant streams, the output filename pattern must
835 contain the string "%v", this string specifies the position of variant stream
836 index in the output media playlist filenames.
839 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
840 -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" \
841 http://example.com/live/out_%v.m3u8
843 This example creates two hls variant streams. The first variant stream will
844 contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
845 second variant stream will contain video stream of bitrate 256k and audio
846 stream of bitrate 32k. Here, two media playlist with file names out_0.m3u8 and
847 out_1.m3u8 will be created.
849 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
850 -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
851 http://example.com/live/out_%v.m3u8
853 This example creates three hls variant streams. The first variant stream will
854 be a video only stream with video bitrate 1000k, the second variant stream will
855 be an audio only stream with bitrate 64k and the third variant stream will be a
856 video only stream with bitrate 256k. Here, three media playlist with file names
857 out_0.m3u8, out_1.m3u8 and out_2.m3u8 will be created.
859 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k \
860 -map 0:a -map 0:a -map 0:v -map 0:v -f hls \
861 -var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
862 -master_pl_name master.m3u8 \
863 http://example.com/live/out_%v.m3u8
865 This example creates two audio only and two video only variant streams. In
866 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
867 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
868 and they are mapped to the two video only variant streams with audio group names
869 'aud_low' and 'aud_high'.
871 By default, a single hls variant containing all the encoded streams is created.
874 Create HLS master playlist with the given name.
877 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
879 This example creates HLS master playlist with name master.m3u8 and it is
880 published at http://example.com/live/
882 @item master_pl_publish_rate
883 Publish master play list repeatedly every after specified number of segment intervals.
886 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
887 -hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
890 This example creates HLS master playlist with name master.m3u8 and keep
891 publishing it repeatedly every after 30 segments i.e. every after 60s.
893 @item http_persistent
894 Use persistent HTTP connections. Applicable only for HTTP output.
903 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
907 Size cannot exceed 256 pixels in any dimension
910 Only BMP and PNG images can be stored
913 If a BMP image is used, it must be one of the following pixel formats:
915 BMP Bit Depth FFmpeg Pixel Format
925 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
928 If a PNG image is used, it must use the rgba pixel format
936 The image file muxer writes video frames to image files.
938 The output filenames are specified by a pattern, which can be used to
939 produce sequentially numbered series of files.
940 The pattern may contain the string "%d" or "%0@var{N}d", this string
941 specifies the position of the characters representing a numbering in
942 the filenames. If the form "%0@var{N}d" is used, the string
943 representing the number in each filename is 0-padded to @var{N}
944 digits. The literal character '%' can be specified in the pattern with
947 If the pattern contains "%d" or "%0@var{N}d", the first filename of
948 the file list specified will contain the number 1, all the following
949 numbers will be sequential.
951 The pattern may contain a suffix which is used to automatically
952 determine the format of the image files to write.
954 For example the pattern "img-%03d.bmp" will specify a sequence of
955 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
956 @file{img-010.bmp}, etc.
957 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
958 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
963 The following example shows how to use @command{ffmpeg} for creating a
964 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
965 taking one image every second from the input video:
967 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
970 Note that with @command{ffmpeg}, if the format is not specified with the
971 @code{-f} option and the output filename specifies an image file
972 format, the image2 muxer is automatically selected, so the previous
973 command can be written as:
975 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
978 Note also that the pattern must not necessarily contain "%d" or
979 "%0@var{N}d", for example to create a single image file
980 @file{img.jpeg} from the start of the input video you can employ the command:
982 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
985 The @option{strftime} option allows you to expand the filename with
986 date and time information. Check the documentation of
987 the @code{strftime()} function for the syntax.
989 For example to generate image files from the @code{strftime()}
990 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
993 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
996 You can set the file name with current frame's PTS:
998 ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
1005 If set to 1, expand the filename with pts from pkt->pts.
1009 Start the sequence from the specified number. Default value is 1.
1012 If set to 1, the filename will always be interpreted as just a
1013 filename, not a pattern, and the corresponding file will be continuously
1014 overwritten with new images. Default value is 0.
1017 If set to 1, expand the filename with date and time information from
1018 @code{strftime()}. Default value is 0.
1021 The image muxer supports the .Y.U.V image file format. This format is
1022 special in that that each image frame consists of three files, for
1023 each of the YUV420P components. To read or write this image file format,
1024 specify the name of the '.Y' file. The muxer will automatically open the
1025 '.U' and '.V' files as required.
1029 Matroska container muxer.
1031 This muxer implements the matroska and webm container specs.
1033 @subsection Metadata
1035 The recognized metadata settings in this muxer are:
1039 Set title name provided to a single track.
1042 Specify the language of the track in the Matroska languages form.
1044 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
1045 639-2/B) form (like "fre" for French), or a language code mixed with a
1046 country code for specialities in languages (like "fre-ca" for Canadian
1050 Set stereo 3D video layout of two views in a single video track.
1052 The following values are recognized:
1057 Both views are arranged side by side, Left-eye view is on the left
1059 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
1061 Both views are arranged in top-bottom orientation, Left-eye view is on top
1062 @item checkerboard_rl
1063 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
1064 @item checkerboard_lr
1065 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
1066 @item row_interleaved_rl
1067 Each view is constituted by a row based interleaving, Right-eye view is first row
1068 @item row_interleaved_lr
1069 Each view is constituted by a row based interleaving, Left-eye view is first row
1070 @item col_interleaved_rl
1071 Both views are arranged in a column based interleaving manner, Right-eye view is first column
1072 @item col_interleaved_lr
1073 Both views are arranged in a column based interleaving manner, Left-eye view is first column
1074 @item anaglyph_cyan_red
1075 All frames are in anaglyph format viewable through red-cyan filters
1077 Both views are arranged side by side, Right-eye view is on the left
1078 @item anaglyph_green_magenta
1079 All frames are in anaglyph format viewable through green-magenta filters
1081 Both eyes laced in one Block, Left-eye view is first
1083 Both eyes laced in one Block, Right-eye view is first
1087 For example a 3D WebM clip can be created using the following command line:
1089 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
1094 This muxer supports the following options:
1097 @item reserve_index_space
1098 By default, this muxer writes the index for seeking (called cues in Matroska
1099 terms) at the end of the file, because it cannot know in advance how much space
1100 to leave for the index at the beginning of the file. However for some use cases
1101 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
1102 index at the beginning of the file.
1104 If this option is set to a non-zero value, the muxer will reserve a given amount
1105 of space in the file header and then try to write the cues there when the muxing
1106 finishes. If the available space does not suffice, muxing will fail. A safe size
1107 for most use cases should be about 50kB per hour of video.
1109 Note that cues are only written if the output is seekable and this option will
1110 have no effect if it is not.
1118 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
1119 defaults to using the MD5 hash function.
1121 @subsection Examples
1123 To compute the MD5 hash of the input converted to raw
1124 audio and video, and store it in the file @file{out.md5}:
1126 ffmpeg -i INPUT -f md5 out.md5
1129 You can print the MD5 to stdout with the command:
1131 ffmpeg -i INPUT -f md5 -
1134 See also the @ref{hash} and @ref{framemd5} muxers.
1136 @section mov, mp4, ismv
1138 MOV/MP4/ISMV (Smooth Streaming) muxer.
1140 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
1141 file has all the metadata about all packets stored in one location
1142 (written at the end of the file, it can be moved to the start for
1143 better playback by adding @var{faststart} to the @var{movflags}, or
1144 using the @command{qt-faststart} tool). A fragmented
1145 file consists of a number of fragments, where packets and metadata
1146 about these packets are stored together. Writing a fragmented
1147 file has the advantage that the file is decodable even if the
1148 writing is interrupted (while a normal MOV/MP4 is undecodable if
1149 it is not properly finished), and it requires less memory when writing
1150 very long files (since writing normal MOV/MP4 files stores info about
1151 every single packet in memory until the file is closed). The downside
1152 is that it is less compatible with other applications.
1156 Fragmentation is enabled by setting one of the AVOptions that define
1157 how to cut the file into fragments:
1160 @item -moov_size @var{bytes}
1161 Reserves space for the moov atom at the beginning of the file instead of placing the
1162 moov atom at the end. If the space reserved is insufficient, muxing will fail.
1163 @item -movflags frag_keyframe
1164 Start a new fragment at each video keyframe.
1165 @item -frag_duration @var{duration}
1166 Create fragments that are @var{duration} microseconds long.
1167 @item -frag_size @var{size}
1168 Create fragments that contain up to @var{size} bytes of payload data.
1169 @item -movflags frag_custom
1170 Allow the caller to manually choose when to cut fragments, by
1171 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
1172 the packets written so far. (This is only useful with other
1173 applications integrating libavformat, not from @command{ffmpeg}.)
1174 @item -min_frag_duration @var{duration}
1175 Don't create fragments that are shorter than @var{duration} microseconds long.
1178 If more than one condition is specified, fragments are cut when
1179 one of the specified conditions is fulfilled. The exception to this is
1180 @code{-min_frag_duration}, which has to be fulfilled for any of the other
1181 conditions to apply.
1183 Additionally, the way the output file is written can be adjusted
1184 through a few other options:
1187 @item -movflags empty_moov
1188 Write an initial moov atom directly at the start of the file, without
1189 describing any samples in it. Generally, an mdat/moov pair is written
1190 at the start of the file, as a normal MOV/MP4 file, containing only
1191 a short portion of the file. With this option set, there is no initial
1192 mdat atom, and the moov atom only describes the tracks but has
1195 This option is implicitly set when writing ismv (Smooth Streaming) files.
1196 @item -movflags separate_moof
1197 Write a separate moof (movie fragment) atom for each track. Normally,
1198 packets for all tracks are written in a moof atom (which is slightly
1199 more efficient), but with this option set, the muxer writes one moof/mdat
1200 pair for each track, making it easier to separate tracks.
1202 This option is implicitly set when writing ismv (Smooth Streaming) files.
1203 @item -movflags faststart
1204 Run a second pass moving the index (moov atom) to the beginning of the file.
1205 This operation can take a while, and will not work in various situations such
1206 as fragmented output, thus it is not enabled by default.
1207 @item -movflags rtphint
1208 Add RTP hinting tracks to the output file.
1209 @item -movflags disable_chpl
1210 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
1211 and a QuickTime chapter track are written to the file. With this option
1212 set, only the QuickTime chapter track will be written. Nero chapters can
1213 cause failures when the file is reprocessed with certain tagging programs, like
1214 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
1215 @item -movflags omit_tfhd_offset
1216 Do not write any absolute base_data_offset in tfhd atoms. This avoids
1217 tying fragments to absolute byte positions in the file/streams.
1218 @item -movflags default_base_moof
1219 Similarly to the omit_tfhd_offset, this flag avoids writing the
1220 absolute base_data_offset field in tfhd atoms, but does so by using
1221 the new default-base-is-moof flag instead. This flag is new from
1222 14496-12:2012. This may make the fragments easier to parse in certain
1223 circumstances (avoiding basing track fragment location calculations
1224 on the implicit end of the previous track fragment).
1226 Specify @code{on} to force writing a timecode track, @code{off} to disable it
1227 and @code{auto} to write a timecode track only for mov and mp4 output (default).
1228 @item -movflags negative_cts_offsets
1229 Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
1230 be negative. This enables the initial sample to have DTS/CTS of zero, and
1231 reduces the need for edit lists for some cases such as video tracks with
1232 B-frames. Additionally, eases conformance with the DASH-IF interoperability
1238 Smooth Streaming content can be pushed in real time to a publishing
1239 point on IIS with this muxer. Example:
1241 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
1244 @subsection Audible AAX
1246 Audible AAX files are encrypted M4B files, and they can be decrypted by specifying a 4 byte activation secret.
1248 ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
1253 The MP3 muxer writes a raw MP3 stream with the following optional features:
1256 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
1257 2.4 are supported, the @code{id3v2_version} private option controls which one is
1258 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
1261 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
1262 The pictures are supplied to the muxer in form of a video stream with a single
1263 packet. There can be any number of those streams, each will correspond to a
1264 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
1265 to APIC @var{description} and @var{picture type} respectively. See
1266 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
1268 Note that the APIC frames must be written at the beginning, so the muxer will
1269 buffer the audio frames until it gets all the pictures. It is therefore advised
1270 to provide the pictures as soon as possible to avoid excessive buffering.
1273 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
1274 default, but will be written only if the output is seekable. The
1275 @code{write_xing} private option can be used to disable it. The frame contains
1276 various information that may be useful to the decoder, like the audio duration
1280 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1281 enabled with the @code{write_id3v1} private option, but as its capabilities are
1282 very limited, its usage is not recommended.
1287 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1289 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1292 To attach a picture to an mp3 file select both the audio and the picture stream
1295 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1296 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1299 Write a "clean" MP3 without any extra features:
1301 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1306 MPEG transport stream muxer.
1308 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1310 The recognized metadata settings in mpegts muxer are @code{service_provider}
1311 and @code{service_name}. If they are not set the default for
1312 @code{service_provider} is @samp{FFmpeg} and the default for
1313 @code{service_name} is @samp{Service01}.
1317 The muxer options are:
1320 @item mpegts_transport_stream_id @var{integer}
1321 Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
1322 Default is @code{0x0001}.
1324 @item mpegts_original_network_id @var{integer}
1325 Set the @samp{original_network_id}. This is unique identifier of a
1326 network in DVB. Its main use is in the unique identification of a service
1327 through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
1330 @item mpegts_service_id @var{integer}
1331 Set the @samp{service_id}, also known as program in DVB. Default is
1334 @item mpegts_service_type @var{integer}
1335 Set the program @samp{service_type}. Default is @code{digital_tv}.
1336 Accepts the following options:
1339 Any hexdecimal value between @code{0x01} to @code{0xff} as defined in
1344 Digital Radio service.
1347 @item advanced_codec_digital_radio
1348 Advanced Codec Digital Radio service.
1349 @item mpeg2_digital_hdtv
1350 MPEG2 Digital HDTV service.
1351 @item advanced_codec_digital_sdtv
1352 Advanced Codec Digital SDTV service.
1353 @item advanced_codec_digital_hdtv
1354 Advanced Codec Digital HDTV service.
1357 @item mpegts_pmt_start_pid @var{integer}
1358 Set the first PID for PMT. Default is @code{0x1000}. Max is @code{0x1f00}.
1360 @item mpegts_start_pid @var{integer}
1361 Set the first PID for data packets. Default is @code{0x0100}. Max is
1364 @item mpegts_m2ts_mode @var{boolean}
1365 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
1368 @item muxrate @var{integer}
1369 Set a constant muxrate. Default is VBR.
1371 @item pes_payload_size @var{integer}
1372 Set minimum PES packet payload in bytes. Default is @code{2930}.
1374 @item mpegts_flags @var{flags}
1375 Set mpegts flags. Accepts the following options:
1377 @item resend_headers
1378 Reemit PAT/PMT before writing the next packet.
1380 Use LATM packetization for AAC.
1381 @item pat_pmt_at_frames
1382 Reemit PAT and PMT at each video frame.
1384 Conform to System B (DVB) instead of System A (ATSC).
1385 @item initial_discontinuity
1386 Mark the initial packet of each stream as discontinuity.
1389 @item resend_headers @var{integer}
1390 Reemit PAT/PMT before writing the next packet. This option is deprecated:
1391 use @option{mpegts_flags} instead.
1393 @item mpegts_copyts @var{boolean}
1394 Preserve original timestamps, if value is set to @code{1}. Default value
1395 is @code{-1}, which results in shifting timestamps so that they start from 0.
1397 @item omit_video_pes_length @var{boolean}
1398 Omit the PES packet length for video packets. Default is @code{1} (true).
1400 @item pcr_period @var{integer}
1401 Override the default PCR retransmission time in milliseconds. Ignored if
1402 variable muxrate is selected. Default is @code{20}.
1404 @item pat_period @var{double}
1405 Maximum time in seconds between PAT/PMT tables.
1407 @item sdt_period @var{double}
1408 Maximum time in seconds between SDT tables.
1410 @item tables_version @var{integer}
1411 Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
1412 This option allows updating stream structure so that standard consumer may
1413 detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
1414 usage) or restart @command{ffmpeg} instance, cyclically changing
1415 @option{tables_version} value:
1418 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1419 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1421 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1422 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1423 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1431 ffmpeg -i file.mpg -c copy \
1432 -mpegts_original_network_id 0x1122 \
1433 -mpegts_transport_stream_id 0x3344 \
1434 -mpegts_service_id 0x5566 \
1435 -mpegts_pmt_start_pid 0x1500 \
1436 -mpegts_start_pid 0x150 \
1437 -metadata service_provider="Some provider" \
1438 -metadata service_name="Some Channel" \
1442 @section mxf, mxf_d10
1448 The muxer options are:
1451 @item store_user_comments @var{bool}
1452 Set if user comments should be stored if available or never.
1453 IRT D-10 does not allow user comments. The default is thus to write them for
1454 mxf but not for mxf_d10
1461 This muxer does not generate any output file, it is mainly useful for
1462 testing or benchmarking purposes.
1464 For example to benchmark decoding with @command{ffmpeg} you can use the
1467 ffmpeg -benchmark -i INPUT -f null out.null
1470 Note that the above command does not read or write the @file{out.null}
1471 file, but specifying the output file is required by the @command{ffmpeg}
1474 Alternatively you can write the command as:
1476 ffmpeg -benchmark -i INPUT -f null -
1482 @item -syncpoints @var{flags}
1483 Change the syncpoint usage in nut:
1485 @item @var{default} use the normal low-overhead seeking aids.
1486 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1487 Use of this option is not recommended, as the resulting files are very damage
1488 sensitive and seeking is not possible. Also in general the overhead from
1489 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1490 all growing data tables, allowing to mux endless streams with limited memory
1491 and without these disadvantages.
1492 @item @var{timestamped} extend the syncpoint with a wallclock field.
1494 The @var{none} and @var{timestamped} flags are experimental.
1495 @item -write_index @var{bool}
1496 Write index at the end, the default is to write an index.
1500 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1505 Ogg container muxer.
1508 @item -page_duration @var{duration}
1509 Preferred page duration, in microseconds. The muxer will attempt to create
1510 pages that are approximately @var{duration} microseconds long. This allows the
1511 user to compromise between seek granularity and container overhead. The default
1512 is 1 second. A value of 0 will fill all segments, making pages as large as
1513 possible. A value of 1 will effectively use 1 packet-per-page in most
1514 situations, giving a small seek granularity at the cost of additional container
1516 @item -serial_offset @var{value}
1517 Serial value from which to set the streams serial number.
1518 Setting it to different and sufficiently large values ensures that the produced
1519 ogg files can be safely chained.
1524 @section segment, stream_segment, ssegment
1526 Basic stream segmenter.
1528 This muxer outputs streams to a number of separate files of nearly
1529 fixed duration. Output filename pattern can be set in a fashion
1530 similar to @ref{image2}, or by using a @code{strftime} template if
1531 the @option{strftime} option is enabled.
1533 @code{stream_segment} is a variant of the muxer used to write to
1534 streaming output formats, i.e. which do not require global headers,
1535 and is recommended for outputting e.g. to MPEG transport stream segments.
1536 @code{ssegment} is a shorter alias for @code{stream_segment}.
1538 Every segment starts with a keyframe of the selected reference stream,
1539 which is set through the @option{reference_stream} option.
1541 Note that if you want accurate splitting for a video file, you need to
1542 make the input key frames correspond to the exact splitting times
1543 expected by the segmenter, or the segment muxer will start the new
1544 segment with the key frame found next after the specified start
1547 The segment muxer works best with a single constant frame rate video.
1549 Optionally it can generate a list of the created segments, by setting
1550 the option @var{segment_list}. The list type is specified by the
1551 @var{segment_list_type} option. The entry filenames in the segment
1552 list are set by default to the basename of the corresponding segment
1555 See also the @ref{hls} muxer, which provides a more specific
1556 implementation for HLS segmentation.
1560 The segment muxer supports the following options:
1563 @item increment_tc @var{1|0}
1564 if set to @code{1}, increment timecode between each segment
1565 If this is selected, the input need to have
1566 a timecode in the first video stream. Default value is
1569 @item reference_stream @var{specifier}
1570 Set the reference stream, as specified by the string @var{specifier}.
1571 If @var{specifier} is set to @code{auto}, the reference is chosen
1572 automatically. Otherwise it must be a stream specifier (see the ``Stream
1573 specifiers'' chapter in the ffmpeg manual) which specifies the
1574 reference stream. The default value is @code{auto}.
1576 @item segment_format @var{format}
1577 Override the inner container format, by default it is guessed by the filename
1580 @item segment_format_options @var{options_list}
1581 Set output format options using a :-separated list of key=value
1582 parameters. Values containing the @code{:} special character must be
1585 @item segment_list @var{name}
1586 Generate also a listfile named @var{name}. If not specified no
1587 listfile is generated.
1589 @item segment_list_flags @var{flags}
1590 Set flags affecting the segment list generation.
1592 It currently supports the following flags:
1595 Allow caching (only affects M3U8 list files).
1598 Allow live-friendly file generation.
1601 @item segment_list_size @var{size}
1602 Update the list file so that it contains at most @var{size}
1603 segments. If 0 the list file will contain all the segments. Default
1606 @item segment_list_entry_prefix @var{prefix}
1607 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1608 By default no prefix is applied.
1610 @item segment_list_type @var{type}
1611 Select the listing format.
1613 The following values are recognized:
1616 Generate a flat list for the created segments, one segment per line.
1619 Generate a list for the created segments, one segment per line,
1620 each line matching the format (comma-separated values):
1622 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1625 @var{segment_filename} is the name of the output file generated by the
1626 muxer according to the provided pattern. CSV escaping (according to
1627 RFC4180) is applied if required.
1629 @var{segment_start_time} and @var{segment_end_time} specify
1630 the segment start and end time expressed in seconds.
1632 A list file with the suffix @code{".csv"} or @code{".ext"} will
1633 auto-select this format.
1635 @samp{ext} is deprecated in favor or @samp{csv}.
1638 Generate an ffconcat file for the created segments. The resulting file
1639 can be read using the FFmpeg @ref{concat} demuxer.
1641 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1642 auto-select this format.
1645 Generate an extended M3U8 file, version 3, compliant with
1646 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1648 A list file with the suffix @code{".m3u8"} will auto-select this format.
1651 If not specified the type is guessed from the list file name suffix.
1653 @item segment_time @var{time}
1654 Set segment duration to @var{time}, the value must be a duration
1655 specification. Default value is "2". See also the
1656 @option{segment_times} option.
1658 Note that splitting may not be accurate, unless you force the
1659 reference stream key-frames at the given time. See the introductory
1660 notice and the examples below.
1662 @item segment_atclocktime @var{1|0}
1663 If set to "1" split at regular clock time intervals starting from 00:00
1664 o'clock. The @var{time} value specified in @option{segment_time} is
1665 used for setting the length of the splitting interval.
1667 For example with @option{segment_time} set to "900" this makes it possible
1668 to create files at 12:00 o'clock, 12:15, 12:30, etc.
1670 Default value is "0".
1672 @item segment_clocktime_offset @var{duration}
1673 Delay the segment splitting times with the specified duration when using
1674 @option{segment_atclocktime}.
1676 For example with @option{segment_time} set to "900" and
1677 @option{segment_clocktime_offset} set to "300" this makes it possible to
1678 create files at 12:05, 12:20, 12:35, etc.
1680 Default value is "0".
1682 @item segment_clocktime_wrap_duration @var{duration}
1683 Force the segmenter to only start a new segment if a packet reaches the muxer
1684 within the specified duration after the segmenting clock time. This way you
1685 can make the segmenter more resilient to backward local time jumps, such as
1686 leap seconds or transition to standard time from daylight savings time.
1688 Default is the maximum possible duration which means starting a new segment
1689 regardless of the elapsed time since the last clock time.
1691 @item segment_time_delta @var{delta}
1692 Specify the accuracy time when selecting the start time for a
1693 segment, expressed as a duration specification. Default value is "0".
1695 When delta is specified a key-frame will start a new segment if its
1696 PTS satisfies the relation:
1698 PTS >= start_time - time_delta
1701 This option is useful when splitting video content, which is always
1702 split at GOP boundaries, in case a key frame is found just before the
1703 specified split time.
1705 In particular may be used in combination with the @file{ffmpeg} option
1706 @var{force_key_frames}. The key frame times specified by
1707 @var{force_key_frames} may not be set accurately because of rounding
1708 issues, with the consequence that a key frame time may result set just
1709 before the specified time. For constant frame rate videos a value of
1710 1/(2*@var{frame_rate}) should address the worst case mismatch between
1711 the specified time and the time set by @var{force_key_frames}.
1713 @item segment_times @var{times}
1714 Specify a list of split points. @var{times} contains a list of comma
1715 separated duration specifications, in increasing order. See also
1716 the @option{segment_time} option.
1718 @item segment_frames @var{frames}
1719 Specify a list of split video frame numbers. @var{frames} contains a
1720 list of comma separated integer numbers, in increasing order.
1722 This option specifies to start a new segment whenever a reference
1723 stream key frame is found and the sequential number (starting from 0)
1724 of the frame is greater or equal to the next value in the list.
1726 @item segment_wrap @var{limit}
1727 Wrap around segment index once it reaches @var{limit}.
1729 @item segment_start_number @var{number}
1730 Set the sequence number of the first segment. Defaults to @code{0}.
1732 @item strftime @var{1|0}
1733 Use the @code{strftime} function to define the name of the new
1734 segments to write. If this is selected, the output segment name must
1735 contain a @code{strftime} function template. Default value is
1738 @item break_non_keyframes @var{1|0}
1739 If enabled, allow segments to start on frames other than keyframes. This
1740 improves behavior on some players when the time between keyframes is
1741 inconsistent, but may make things worse on others, and can cause some oddities
1742 during seeking. Defaults to @code{0}.
1744 @item reset_timestamps @var{1|0}
1745 Reset timestamps at the beginning of each segment, so that each segment
1746 will start with near-zero timestamps. It is meant to ease the playback
1747 of the generated segments. May not work with some combinations of
1748 muxers/codecs. It is set to @code{0} by default.
1750 @item initial_offset @var{offset}
1751 Specify timestamp offset to apply to the output packet timestamps. The
1752 argument must be a time duration specification, and defaults to 0.
1754 @item write_empty_segments @var{1|0}
1755 If enabled, write an empty segment if there are no packets during the period a
1756 segment would usually span. Otherwise, the segment will be filled with the next
1757 packet written. Defaults to @code{0}.
1760 Make sure to require a closed GOP when encoding and to set the GOP
1761 size to fit your segment time constraint.
1763 @subsection Examples
1767 Remux the content of file @file{in.mkv} to a list of segments
1768 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
1769 generated segments to @file{out.list}:
1771 ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
1775 Segment input and set output format options for the output segments:
1777 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
1781 Segment the input file according to the split points specified by the
1782 @var{segment_times} option:
1784 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
1788 Use the @command{ffmpeg} @option{force_key_frames}
1789 option to force key frames in the input at the specified location, together
1790 with the segment option @option{segment_time_delta} to account for
1791 possible roundings operated when setting key frame times.
1793 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
1794 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
1796 In order to force key frames on the input file, transcoding is
1800 Segment the input file by splitting the input file according to the
1801 frame numbers sequence specified with the @option{segment_frames} option:
1803 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
1807 Convert the @file{in.mkv} to TS segments using the @code{libx264}
1808 and @code{aac} encoders:
1810 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
1814 Segment the input file, and create an M3U8 live playlist (can be used
1815 as live HLS source):
1817 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
1818 -segment_list_flags +live -segment_time 10 out%03d.mkv
1822 @section smoothstreaming
1824 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
1828 Specify the number of fragments kept in the manifest. Default 0 (keep all).
1830 @item extra_window_size
1831 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
1833 @item lookahead_count
1834 Specify the number of lookahead fragments. Default 2.
1836 @item min_frag_duration
1837 Specify the minimum fragment duration (in microseconds). Default 5000000.
1839 @item remove_at_exit
1840 Specify whether to remove all fragments when finished. Default 0 (do not remove).
1847 The fifo pseudo-muxer allows the separation of encoding and muxing by using
1848 first-in-first-out queue and running the actual muxer in a separate thread. This
1849 is especially useful in combination with the @ref{tee} muxer and can be used to
1850 send data to several destinations with different reliability/writing speed/latency.
1852 API users should be aware that callback functions (interrupt_callback,
1853 io_open and io_close) used within its AVFormatContext must be thread-safe.
1855 The behavior of the fifo muxer if the queue fills up or if the output fails is
1861 output can be transparently restarted with configurable delay between retries
1862 based on real time or time of the processed stream.
1865 encoding can be blocked during temporary failure, or continue transparently
1866 dropping packets in case fifo queue fills up.
1873 Specify the format name. Useful if it cannot be guessed from the
1877 Specify size of the queue (number of packets). Default value is 60.
1880 Specify format options for the underlying muxer. Muxer options can be specified
1881 as a list of @var{key}=@var{value} pairs separated by ':'.
1883 @item drop_pkts_on_overflow @var{bool}
1884 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
1885 rather than blocking the encoder. This makes it possible to continue streaming without
1886 delaying the input, at the cost of omitting part of the stream. By default
1887 this option is set to 0 (false), so in such cases the encoder will be blocked
1888 until the muxer processes some of the packets and none of them is lost.
1890 @item attempt_recovery @var{bool}
1891 If failure occurs, attempt to recover the output. This is especially useful
1892 when used with network output, since it makes it possible to restart streaming transparently.
1893 By default this option is set to 0 (false).
1895 @item max_recovery_attempts
1896 Sets maximum number of successive unsuccessful recovery attempts after which
1897 the output fails permanently. By default this option is set to 0 (unlimited).
1899 @item recovery_wait_time @var{duration}
1900 Waiting time before the next recovery attempt after previous unsuccessful
1901 recovery attempt. Default value is 5 seconds.
1903 @item recovery_wait_streamtime @var{bool}
1904 If set to 0 (false), the real time is used when waiting for the recovery
1905 attempt (i.e. the recovery will be attempted after at least
1906 recovery_wait_time seconds).
1907 If set to 1 (true), the time of the processed stream is taken into account
1908 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
1909 seconds of the stream is omitted).
1910 By default, this option is set to 0 (false).
1912 @item recover_any_error @var{bool}
1913 If set to 1 (true), recovery will be attempted regardless of type of the error
1914 causing the failure. By default this option is set to 0 (false) and in case of
1915 certain (usually permanent) errors the recovery is not attempted even when
1916 @var{attempt_recovery} is set to 1.
1918 @item restart_with_keyframe @var{bool}
1919 Specify whether to wait for the keyframe after recovering from
1920 queue overflow or failure. This option is set to 0 (false) by default.
1924 @subsection Examples
1929 Stream something to rtmp server, continue processing the stream at real-time
1930 rate even in case of temporary failure (network outage) and attempt to recover
1931 streaming every second indefinitely.
1933 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
1934 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
1942 The tee muxer can be used to write the same data to several files or any
1943 other kind of muxer. It can be used, for example, to both stream a video to
1944 the network and save it to disk at the same time.
1946 It is different from specifying several outputs to the @command{ffmpeg}
1947 command-line tool because the audio and video data will be encoded only once
1948 with the tee muxer; encoding can be a very expensive process. It is not
1949 useful when using the libavformat API directly because it is then possible
1950 to feed the same packets to several muxers directly.
1954 @item use_fifo @var{bool}
1955 If set to 1, slave outputs will be processed in separate thread using @ref{fifo}
1956 muxer. This allows to compensate for different speed/latency/reliability of
1957 outputs and setup transparent recovery. By default this feature is turned off.
1960 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
1964 The slave outputs are specified in the file name given to the muxer,
1965 separated by '|'. If any of the slave name contains the '|' separator,
1966 leading or trailing spaces or any special character, it must be
1967 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
1968 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
1970 Muxer options can be specified for each slave by prepending them as a list of
1971 @var{key}=@var{value} pairs separated by ':', between square brackets. If
1972 the options values contain a special character or the ':' separator, they
1973 must be escaped; note that this is a second level escaping.
1975 The following special options are also recognized:
1978 Specify the format name. Useful if it cannot be guessed from the
1981 @item bsfs[/@var{spec}]
1982 Specify a list of bitstream filters to apply to the specified
1985 @item use_fifo @var{bool}
1986 This allows to override tee muxer use_fifo option for individual slave muxer.
1989 This allows to override tee muxer fifo_options for individual slave muxer.
1992 It is possible to specify to which streams a given bitstream filter
1993 applies, by appending a stream specifier to the option separated by
1994 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
1995 stream specifiers}). If the stream specifier is not specified, the
1996 bitstream filters will be applied to all streams in the output.
1998 Several bitstream filters can be specified, separated by ",".
2001 Select the streams that should be mapped to the slave output,
2002 specified by a stream specifier. If not specified, this defaults to
2003 all the input streams. You may use multiple stream specifiers
2004 separated by commas (@code{,}) e.g.: @code{a:0,v}
2007 Specify behaviour on output failure. This can be set to either @code{abort} (which is
2008 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
2009 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
2010 will continue without being affected.
2013 @subsection Examples
2017 Encode something and both archive it in a WebM file and stream it
2018 as MPEG-TS over UDP (the streams need to be explicitly mapped):
2020 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2021 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2025 As above, but continue streaming even if output to local file fails
2026 (for example local drive fills up):
2028 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2029 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2033 Use @command{ffmpeg} to encode the input, and send the output
2034 to three different destinations. The @code{dump_extra} bitstream
2035 filter is used to add extradata information to all the output video
2036 keyframes packets, as requested by the MPEG-TS format. The select
2037 option is applied to @file{out.aac} in order to make it contain only
2040 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2041 -f tee "[bsfs/v=dump_extra]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
2045 As below, but select only stream @code{a:1} for the audio output. Note
2046 that a second level escaping must be performed, as ":" is a special
2047 character used to separate options.
2049 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2050 -f tee "[bsfs/v=dump_extra]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
2054 Note: some codecs may need different options depending on the output format;
2055 the auto-detection of this can not work with the tee muxer. The main example
2056 is the @option{global_header} flag.
2058 @section webm_dash_manifest
2060 WebM DASH Manifest muxer.
2062 This muxer implements the WebM DASH Manifest specification to generate the DASH
2063 manifest XML. It also supports manifest generation for DASH live streams.
2065 For more information see:
2069 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
2071 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
2076 This muxer supports the following options:
2079 @item adaptation_sets
2080 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
2081 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
2082 audio and video streams. Any number of adaptation sets can be added using this option.
2085 Set this to 1 to create a live stream DASH Manifest. Default: 0.
2087 @item chunk_start_index
2088 Start index of the first chunk. This will go in the @samp{startNumber} attribute
2089 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
2091 @item chunk_duration_ms
2092 Duration of each chunk in milliseconds. This will go in the @samp{duration}
2093 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
2095 @item utc_timing_url
2096 URL of the page that will return the UTC timestamp in ISO format. This will go
2097 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
2100 @item time_shift_buffer_depth
2101 Smallest time (in seconds) shifting buffer for which any Representation is
2102 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
2103 attribute of the @samp{MPD} element. Default: 60.
2105 @item minimum_update_period
2106 Minimum update period (in seconds) of the manifest. This will go in the
2107 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
2113 ffmpeg -f webm_dash_manifest -i video1.webm \
2114 -f webm_dash_manifest -i video2.webm \
2115 -f webm_dash_manifest -i audio1.webm \
2116 -f webm_dash_manifest -i audio2.webm \
2117 -map 0 -map 1 -map 2 -map 3 \
2119 -f webm_dash_manifest \
2120 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
2126 WebM Live Chunk Muxer.
2128 This muxer writes out WebM headers and chunks as separate files which can be
2129 consumed by clients that support WebM Live streams via DASH.
2133 This muxer supports the following options:
2136 @item chunk_start_index
2137 Index of the first chunk (defaults to 0).
2140 Filename of the header where the initialization data will be written.
2142 @item audio_chunk_duration
2143 Duration of each audio chunk in milliseconds (defaults to 5000).
2148 ffmpeg -f v4l2 -i /dev/video0 \
2152 -s 640x360 -keyint_min 30 -g 30 \
2154 -header webm_live_video_360.hdr \
2155 -chunk_start_index 1 \
2156 webm_live_video_360_%d.chk \
2161 -header webm_live_audio_128.hdr \
2162 -chunk_start_index 1 \
2163 -audio_chunk_duration 1000 \
2164 webm_live_audio_128_%d.chk