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{-formats} of the ff* tools will display the list of
19 A description of some of the currently available muxers follows.
24 Audio Interchange File Format muxer.
28 It accepts the following options:
32 Enable ID3v2 tags writing when set to 1. Default is 0 (disabled).
35 Select ID3v2 version to write. Currently only version 3 and 4 (aka.
36 ID3v2.3 and ID3v2.4) are supported. The default is version 4.
43 Advanced Systems Format muxer.
45 Note that Windows Media Audio (wma) and Windows Media Video (wmv) use this
50 It accepts the following options:
54 Set the muxer packet size. By tuning this setting you may reduce data
55 fragmentation or muxer overhead depending on your source. Default value is
56 3200, minimum is 100, maximum is 64k.
63 Chromaprint fingerprinter
65 This muxer feeds audio data to the Chromaprint library, which generates
66 a fingerprint for the provided audio data. It takes a single signed
67 native-endian 16-bit raw audio stream.
72 @item silence_threshold
73 Threshold for detecting silence, ranges from 0 to 32767. -1 for default
74 (required for use with the AcoustID service).
77 Algorithm index to fingerprint with.
80 Format to output the fingerprint as. Accepts the following options:
83 Binary raw fingerprint
86 Binary compressed fingerprint
89 Base64 compressed fingerprint
98 CRC (Cyclic Redundancy Check) testing format.
100 This muxer computes and prints the Adler-32 CRC of all the input audio
101 and video frames. By default audio frames are converted to signed
102 16-bit raw audio and video frames to raw video before computing the
105 The output of the muxer consists of a single line of the form:
106 CRC=0x@var{CRC}, where @var{CRC} is a hexadecimal number 0-padded to
107 8 digits containing the CRC for all the decoded input frames.
109 See also the @ref{framecrc} muxer.
113 For example to compute the CRC of the input, and store it in the file
116 ffmpeg -i INPUT -f crc out.crc
119 You can print the CRC to stdout with the command:
121 ffmpeg -i INPUT -f crc -
124 You can select the output format of each frame with @command{ffmpeg} by
125 specifying the audio and video codec and format. For example to
126 compute the CRC of the input audio converted to PCM unsigned 8-bit
127 and the input video converted to MPEG-2 video, use the command:
129 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f crc -
134 Adobe Flash Video Format muxer.
136 This muxer accepts the following options:
140 @item flvflags @var{flags}
145 @item aac_seq_header_detect
146 Place AAC sequence header based on audio stream data.
148 @item no_sequence_end
149 Disable sequence end tag.
152 Disable metadata tag.
154 @item no_duration_filesize
155 Disable duration and filesize in metadata when they are equal to zero
156 at the end of stream. (Be used to non-seekable living stream).
158 @item add_keyframe_index
159 Used to facilitate seeking; particularly for HTTP pseudo streaming.
166 Per-packet CRC (Cyclic Redundancy Check) testing format.
168 This muxer computes and prints the Adler-32 CRC for each audio
169 and video packet. By default audio frames are converted to signed
170 16-bit raw audio and video frames to raw video before computing the
173 The output of the muxer consists of a line for each audio and video
176 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
179 @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
184 For example to compute the CRC of the audio and video frames in
185 @file{INPUT}, converted to raw audio and video packets, and store it
186 in the file @file{out.crc}:
188 ffmpeg -i INPUT -f framecrc out.crc
191 To print the information to stdout, use the command:
193 ffmpeg -i INPUT -f framecrc -
196 With @command{ffmpeg}, you can select the output format to which the
197 audio and video frames are encoded before computing the CRC for each
198 packet by specifying the audio and video codec. For example, to
199 compute the CRC of each decoded input audio frame converted to PCM
200 unsigned 8-bit and of each decoded input video frame converted to
201 MPEG-2 video, use the command:
203 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
206 See also the @ref{crc} muxer.
211 Per-packet hash testing format.
213 This muxer computes and prints a cryptographic hash for each audio
214 and video packet. This can be used for packet-by-packet equality
215 checks without having to individually do a binary comparison on each.
217 By default audio frames are converted to signed 16-bit raw audio and
218 video frames to raw video before computing the hash, but the output
219 of explicit conversions to other codecs can also be used. It uses the
220 SHA-256 cryptographic hash function by default, but supports several
223 The output of the muxer consists of a line for each audio and video
226 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
229 @var{hash} is a hexadecimal number representing the computed hash
233 @item hash @var{algorithm}
234 Use the cryptographic hash function specified by the string @var{algorithm}.
235 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
236 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
237 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
238 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
244 To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
245 converted to raw audio and video packets, and store it in the file
248 ffmpeg -i INPUT -f framehash out.sha256
251 To print the information to stdout, using the MD5 hash function, use
254 ffmpeg -i INPUT -f framehash -hash md5 -
257 See also the @ref{hash} muxer.
262 Per-packet MD5 testing format.
264 This is a variant of the @ref{framehash} muxer. Unlike that muxer,
265 it defaults to using the MD5 hash function.
269 To compute the MD5 hash of the audio and video frames in @file{INPUT},
270 converted to raw audio and video packets, and store it in the file
273 ffmpeg -i INPUT -f framemd5 out.md5
276 To print the information to stdout, use the command:
278 ffmpeg -i INPUT -f framemd5 -
281 See also the @ref{framehash} and @ref{md5} muxers.
288 It accepts the following options:
292 Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
293 for looping indefinitely (default).
296 Force the delay (expressed in centiseconds) after the last frame. Each frame
297 ends with a delay until the next frame. The default is @code{-1}, which is a
298 special value to tell the muxer to re-use the previous delay. In case of a
299 loop, you might want to customize this value to mark a pause for instance.
302 For example, to encode a gif looping 10 times, with a 5 seconds delay between
305 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
308 Note 1: if you wish to extract the frames into separate GIF files, you need to
309 force the @ref{image2} muxer:
311 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
314 Note 2: the GIF format has a very large time base: the delay between two frames
315 can therefore not be smaller than one centi second.
322 This muxer computes and prints a cryptographic hash of all the input
323 audio and video frames. This can be used for equality checks without
324 having to do a complete binary comparison.
326 By default audio frames are converted to signed 16-bit raw audio and
327 video frames to raw video before computing the hash, but the output
328 of explicit conversions to other codecs can also be used. Timestamps
329 are ignored. It uses the SHA-256 cryptographic hash function by default,
330 but supports several other algorithms.
332 The output of the muxer consists of a single line of the form:
333 @var{algo}=@var{hash}, where @var{algo} is a short string representing
334 the hash function used, and @var{hash} is a hexadecimal number
335 representing the computed hash.
338 @item hash @var{algorithm}
339 Use the cryptographic hash function specified by the string @var{algorithm}.
340 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
341 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
342 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
343 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
349 To compute the SHA-256 hash of the input converted to raw audio and
350 video, and store it in the file @file{out.sha256}:
352 ffmpeg -i INPUT -f hash out.sha256
355 To print an MD5 hash to stdout use the command:
357 ffmpeg -i INPUT -f hash -hash md5 -
360 See also the @ref{framehash} muxer.
365 Apple HTTP Live Streaming muxer that segments MPEG-TS according to
366 the HTTP Live Streaming (HLS) specification.
368 It creates a playlist file, and one or more segment files. The output filename
369 specifies the playlist filename.
371 By default, the muxer creates a file for each segment produced. These files
372 have the same name as the playlist, followed by a sequential number and a
375 For example, to convert an input file with @command{ffmpeg}:
377 ffmpeg -i in.nut out.m3u8
379 This example will produce the playlist, @file{out.m3u8}, and segment files:
380 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
382 See also the @ref{segment} muxer, which provides a more generic and
383 flexible implementation of a segmenter, and can be used to perform HLS
388 This muxer supports the following options:
391 @item hls_init_time @var{seconds}
392 Set the initial target segment length in seconds. Default value is @var{0}.
393 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
394 After the initial playlist is filled @command{ffmpeg} will cut segments
395 at duration equal to @code{hls_time}
397 @item hls_time @var{seconds}
398 Set the target segment length in seconds. Default value is 2.
399 Segment will be cut on the next key frame after this time has passed.
401 @item hls_list_size @var{size}
402 Set the maximum number of playlist entries. If set to 0 the list file
403 will contain all the segments. Default value is 5.
405 @item hls_ts_options @var{options_list}
406 Set output format options using a :-separated list of key=value
407 parameters. Values containing @code{:} special characters must be
410 @item hls_wrap @var{wrap}
411 Set the number after which the segment filename number (the number
412 specified in each segment file) wraps. If set to 0 the number will be
413 never wrapped. Default value is 0.
415 This option is useful to avoid to fill the disk with many segment
416 files, and limits the maximum number of segment files written to disk
419 @item start_number @var{number}
420 Start the playlist sequence number from @var{number}. Default value is
423 @item hls_allow_cache @var{allowcache}
424 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
426 @item hls_base_url @var{baseurl}
427 Append @var{baseurl} to every entry in the playlist.
428 Useful to generate playlists with absolute paths.
430 Note that the playlist sequence number must be unique for each segment
431 and it is not to be confused with the segment filename sequence number
432 which can be cyclic, for example if the @option{wrap} option is
435 @item hls_segment_filename @var{filename}
436 Set the segment filename. Unless @code{hls_flags single_file} is set,
437 @var{filename} is used as a string format with the segment number:
439 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
441 This example will produce the playlist, @file{out.m3u8}, and segment files:
442 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
444 @var{filename} may contain full path or relative path specification,
445 but only the file name part without any path info will be contained in the m3u8 segment list.
446 Should a relative path be specified, the path of the created segment
447 files will be relative to the current working directory.
448 When use_localtime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
452 Use strftime() on @var{filename} to expand the segment filename with localtime.
453 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
454 hls_flag and %%d will be the specifier.
456 ffmpeg -i in.nut -use_localtime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
458 This example will produce the playlist, @file{out.m3u8}, and segment files:
459 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
460 Note: On some systems/environments, the @code{%s} specifier is not available. See
461 @code{strftime()} documentation.
463 ffmpeg -i in.nut -use_localtime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
465 This example will produce the playlist, @file{out.m3u8}, and segment files:
466 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
468 @item use_localtime_mkdir
469 Used together with -use_localtime, it will create all subdirectories which
470 is expanded in @var{filename}.
472 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
474 This example will create a directory 201560215 (if it does not exist), and then
475 produce the playlist, @file{out.m3u8}, and segment files:
476 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
479 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
481 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
482 produce the playlist, @file{out.m3u8}, and segment files:
483 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
486 @item hls_key_info_file @var{key_info_file}
487 Use the information in @var{key_info_file} for segment encryption. The first
488 line of @var{key_info_file} specifies the key URI written to the playlist. The
489 key URL is used to access the encryption key during playback. The second line
490 specifies the path to the key file used to obtain the key during the encryption
491 process. The key file is read as a single packed array of 16 octets in binary
492 format. The optional third line specifies the initialization vector (IV) as a
493 hexadecimal string to be used instead of the segment sequence number (default)
494 for encryption. Changes to @var{key_info_file} will result in segment
495 encryption with the new key/IV and an entry in the playlist for the new key
498 Key info file format:
507 http://server/file.key
512 Example key file paths:
520 0123456789ABCDEF0123456789ABCDEF
523 Key info file example:
525 http://server/file.key
527 0123456789ABCDEF0123456789ABCDEF
530 Example shell script:
534 openssl rand 16 > file.key
535 echo $BASE_URL/file.key > file.keyinfo
536 echo file.key >> file.keyinfo
537 echo $(openssl rand -hex 16) >> file.keyinfo
538 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
539 -hls_key_info_file file.keyinfo out.m3u8
543 @item hls_flags @var{flags}
548 If this flag is set, the muxer will store all segments in a single MPEG-TS
549 file, and will use byte ranges in the playlist. HLS playlists generated with
550 this way will have the version number 4.
553 ffmpeg -i in.nut -hls_flags single_file out.m3u8
555 Will produce the playlist, @file{out.m3u8}, and a single segment file,
558 @item delete_segments
559 Segment files removed from the playlist are deleted after a period of time
560 equal to the duration of the segment plus the duration of the playlist.
563 Append new segments into the end of old segment list,
564 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
566 @item round_durations
567 Round the duration info in the playlist file segment info to integer
568 values, instead of using floating point.
571 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
572 first segment's information.
575 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
578 Allow segments to start on frames other than keyframes. This improves
579 behavior on some players when the time between keyframes is inconsistent,
580 but may make things worse on others, and can cause some oddities during
581 seeking. This flag should be used with the @code{hls_time} option.
583 @item program_date_time
584 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
586 @item second_level_segment_index
587 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
588 besides date/time values when use_localtime is on.
589 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
591 @item second_level_segment_size
592 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
593 expression besides date/time values when use_localtime is on.
594 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
596 @item second_level_segment_duration
597 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
598 expression besides date/time values when use_localtime is on.
599 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
602 ffmpeg -i sample.mpeg \
603 -f hls -hls_time 3 -hls_list_size 5 \
604 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
605 -use_localtime 1 -use_localtime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
607 This will produce segments like this:
608 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
613 @item hls_playlist_type event
614 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
615 @option{hls_list_size} to 0; the playlist can only be appended to.
617 @item hls_playlist_type vod
618 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
619 @option{hls_list_size} to 0; the playlist must not change.
622 Use the given HTTP method to create the hls files.
624 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
626 This example will upload all the mpegts segment files to the HTTP
627 server using the HTTP PUT method, and update the m3u8 files every
628 @code{refresh} times using the same method.
629 Note that the HTTP server must support the given method for uploading
638 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
642 Size cannot exceed 256 pixels in any dimension
645 Only BMP and PNG images can be stored
648 If a BMP image is used, it must be one of the following pixel formats:
650 BMP Bit Depth FFmpeg Pixel Format
660 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
663 If a PNG image is used, it must use the rgba pixel format
671 The image file muxer writes video frames to image files.
673 The output filenames are specified by a pattern, which can be used to
674 produce sequentially numbered series of files.
675 The pattern may contain the string "%d" or "%0@var{N}d", this string
676 specifies the position of the characters representing a numbering in
677 the filenames. If the form "%0@var{N}d" is used, the string
678 representing the number in each filename is 0-padded to @var{N}
679 digits. The literal character '%' can be specified in the pattern with
682 If the pattern contains "%d" or "%0@var{N}d", the first filename of
683 the file list specified will contain the number 1, all the following
684 numbers will be sequential.
686 The pattern may contain a suffix which is used to automatically
687 determine the format of the image files to write.
689 For example the pattern "img-%03d.bmp" will specify a sequence of
690 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
691 @file{img-010.bmp}, etc.
692 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
693 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
698 The following example shows how to use @command{ffmpeg} for creating a
699 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
700 taking one image every second from the input video:
702 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
705 Note that with @command{ffmpeg}, if the format is not specified with the
706 @code{-f} option and the output filename specifies an image file
707 format, the image2 muxer is automatically selected, so the previous
708 command can be written as:
710 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
713 Note also that the pattern must not necessarily contain "%d" or
714 "%0@var{N}d", for example to create a single image file
715 @file{img.jpeg} from the start of the input video you can employ the command:
717 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
720 The @option{strftime} option allows you to expand the filename with
721 date and time information. Check the documentation of
722 the @code{strftime()} function for the syntax.
724 For example to generate image files from the @code{strftime()}
725 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
728 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
735 Start the sequence from the specified number. Default value is 0.
738 If set to 1, the filename will always be interpreted as just a
739 filename, not a pattern, and the corresponding file will be continuously
740 overwritten with new images. Default value is 0.
743 If set to 1, expand the filename with date and time information from
744 @code{strftime()}. Default value is 0.
747 The image muxer supports the .Y.U.V image file format. This format is
748 special in that that each image frame consists of three files, for
749 each of the YUV420P components. To read or write this image file format,
750 specify the name of the '.Y' file. The muxer will automatically open the
751 '.U' and '.V' files as required.
755 Matroska container muxer.
757 This muxer implements the matroska and webm container specs.
761 The recognized metadata settings in this muxer are:
765 Set title name provided to a single track.
768 Specify the language of the track in the Matroska languages form.
770 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
771 639-2/B) form (like "fre" for French), or a language code mixed with a
772 country code for specialities in languages (like "fre-ca" for Canadian
776 Set stereo 3D video layout of two views in a single video track.
778 The following values are recognized:
783 Both views are arranged side by side, Left-eye view is on the left
785 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
787 Both views are arranged in top-bottom orientation, Left-eye view is on top
788 @item checkerboard_rl
789 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
790 @item checkerboard_lr
791 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
792 @item row_interleaved_rl
793 Each view is constituted by a row based interleaving, Right-eye view is first row
794 @item row_interleaved_lr
795 Each view is constituted by a row based interleaving, Left-eye view is first row
796 @item col_interleaved_rl
797 Both views are arranged in a column based interleaving manner, Right-eye view is first column
798 @item col_interleaved_lr
799 Both views are arranged in a column based interleaving manner, Left-eye view is first column
800 @item anaglyph_cyan_red
801 All frames are in anaglyph format viewable through red-cyan filters
803 Both views are arranged side by side, Right-eye view is on the left
804 @item anaglyph_green_magenta
805 All frames are in anaglyph format viewable through green-magenta filters
807 Both eyes laced in one Block, Left-eye view is first
809 Both eyes laced in one Block, Right-eye view is first
813 For example a 3D WebM clip can be created using the following command line:
815 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
820 This muxer supports the following options:
823 @item reserve_index_space
824 By default, this muxer writes the index for seeking (called cues in Matroska
825 terms) at the end of the file, because it cannot know in advance how much space
826 to leave for the index at the beginning of the file. However for some use cases
827 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
828 index at the beginning of the file.
830 If this option is set to a non-zero value, the muxer will reserve a given amount
831 of space in the file header and then try to write the cues there when the muxing
832 finishes. If the available space does not suffice, muxing will fail. A safe size
833 for most use cases should be about 50kB per hour of video.
835 Note that cues are only written if the output is seekable and this option will
836 have no effect if it is not.
844 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
845 defaults to using the MD5 hash function.
849 To compute the MD5 hash of the input converted to raw
850 audio and video, and store it in the file @file{out.md5}:
852 ffmpeg -i INPUT -f md5 out.md5
855 You can print the MD5 to stdout with the command:
857 ffmpeg -i INPUT -f md5 -
860 See also the @ref{hash} and @ref{framemd5} muxers.
862 @section mov, mp4, ismv
864 MOV/MP4/ISMV (Smooth Streaming) muxer.
866 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
867 file has all the metadata about all packets stored in one location
868 (written at the end of the file, it can be moved to the start for
869 better playback by adding @var{faststart} to the @var{movflags}, or
870 using the @command{qt-faststart} tool). A fragmented
871 file consists of a number of fragments, where packets and metadata
872 about these packets are stored together. Writing a fragmented
873 file has the advantage that the file is decodable even if the
874 writing is interrupted (while a normal MOV/MP4 is undecodable if
875 it is not properly finished), and it requires less memory when writing
876 very long files (since writing normal MOV/MP4 files stores info about
877 every single packet in memory until the file is closed). The downside
878 is that it is less compatible with other applications.
882 Fragmentation is enabled by setting one of the AVOptions that define
883 how to cut the file into fragments:
886 @item -moov_size @var{bytes}
887 Reserves space for the moov atom at the beginning of the file instead of placing the
888 moov atom at the end. If the space reserved is insufficient, muxing will fail.
889 @item -movflags frag_keyframe
890 Start a new fragment at each video keyframe.
891 @item -frag_duration @var{duration}
892 Create fragments that are @var{duration} microseconds long.
893 @item -frag_size @var{size}
894 Create fragments that contain up to @var{size} bytes of payload data.
895 @item -movflags frag_custom
896 Allow the caller to manually choose when to cut fragments, by
897 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
898 the packets written so far. (This is only useful with other
899 applications integrating libavformat, not from @command{ffmpeg}.)
900 @item -min_frag_duration @var{duration}
901 Don't create fragments that are shorter than @var{duration} microseconds long.
904 If more than one condition is specified, fragments are cut when
905 one of the specified conditions is fulfilled. The exception to this is
906 @code{-min_frag_duration}, which has to be fulfilled for any of the other
909 Additionally, the way the output file is written can be adjusted
910 through a few other options:
913 @item -movflags empty_moov
914 Write an initial moov atom directly at the start of the file, without
915 describing any samples in it. Generally, an mdat/moov pair is written
916 at the start of the file, as a normal MOV/MP4 file, containing only
917 a short portion of the file. With this option set, there is no initial
918 mdat atom, and the moov atom only describes the tracks but has
921 This option is implicitly set when writing ismv (Smooth Streaming) files.
922 @item -movflags separate_moof
923 Write a separate moof (movie fragment) atom for each track. Normally,
924 packets for all tracks are written in a moof atom (which is slightly
925 more efficient), but with this option set, the muxer writes one moof/mdat
926 pair for each track, making it easier to separate tracks.
928 This option is implicitly set when writing ismv (Smooth Streaming) files.
929 @item -movflags faststart
930 Run a second pass moving the index (moov atom) to the beginning of the file.
931 This operation can take a while, and will not work in various situations such
932 as fragmented output, thus it is not enabled by default.
933 @item -movflags rtphint
934 Add RTP hinting tracks to the output file.
935 @item -movflags disable_chpl
936 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
937 and a QuickTime chapter track are written to the file. With this option
938 set, only the QuickTime chapter track will be written. Nero chapters can
939 cause failures when the file is reprocessed with certain tagging programs, like
940 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
941 @item -movflags omit_tfhd_offset
942 Do not write any absolute base_data_offset in tfhd atoms. This avoids
943 tying fragments to absolute byte positions in the file/streams.
944 @item -movflags default_base_moof
945 Similarly to the omit_tfhd_offset, this flag avoids writing the
946 absolute base_data_offset field in tfhd atoms, but does so by using
947 the new default-base-is-moof flag instead. This flag is new from
948 14496-12:2012. This may make the fragments easier to parse in certain
949 circumstances (avoiding basing track fragment location calculations
950 on the implicit end of the previous track fragment).
952 Specify @code{on} to force writing a timecode track, @code{off} to disable it
953 and @code{auto} to write a timecode track only for mov and mp4 output (default).
958 Smooth Streaming content can be pushed in real time to a publishing
959 point on IIS with this muxer. Example:
961 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
964 @subsection Audible AAX
966 Audible AAX files are encrypted M4B files, and they can be decrypted by specifying a 4 byte activation secret.
968 ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
973 The MP3 muxer writes a raw MP3 stream with the following optional features:
976 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
977 2.4 are supported, the @code{id3v2_version} private option controls which one is
978 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
981 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
982 The pictures are supplied to the muxer in form of a video stream with a single
983 packet. There can be any number of those streams, each will correspond to a
984 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
985 to APIC @var{description} and @var{picture type} respectively. See
986 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
988 Note that the APIC frames must be written at the beginning, so the muxer will
989 buffer the audio frames until it gets all the pictures. It is therefore advised
990 to provide the pictures as soon as possible to avoid excessive buffering.
993 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
994 default, but will be written only if the output is seekable. The
995 @code{write_xing} private option can be used to disable it. The frame contains
996 various information that may be useful to the decoder, like the audio duration
1000 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1001 enabled with the @code{write_id3v1} private option, but as its capabilities are
1002 very limited, its usage is not recommended.
1007 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1009 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1012 To attach a picture to an mp3 file select both the audio and the picture stream
1015 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1016 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1019 Write a "clean" MP3 without any extra features:
1021 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1026 MPEG transport stream muxer.
1028 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1030 The recognized metadata settings in mpegts muxer are @code{service_provider}
1031 and @code{service_name}. If they are not set the default for
1032 @code{service_provider} is "FFmpeg" and the default for
1033 @code{service_name} is "Service01".
1037 The muxer options are:
1040 @item mpegts_original_network_id @var{number}
1041 Set the original_network_id (default 0x0001). This is unique identifier
1042 of a network in DVB. Its main use is in the unique identification of a
1043 service through the path Original_Network_ID, Transport_Stream_ID.
1044 @item mpegts_transport_stream_id @var{number}
1045 Set the transport_stream_id (default 0x0001). This identifies a
1047 @item mpegts_service_id @var{number}
1048 Set the service_id (default 0x0001) also known as program in DVB.
1049 @item mpegts_service_type @var{number}
1050 Set the program service_type (default @var{digital_tv}), see below
1051 a list of pre defined values.
1052 @item mpegts_pmt_start_pid @var{number}
1053 Set the first PID for PMT (default 0x1000, max 0x1f00).
1054 @item mpegts_start_pid @var{number}
1055 Set the first PID for data packets (default 0x0100, max 0x0f00).
1056 @item mpegts_m2ts_mode @var{number}
1057 Enable m2ts mode if set to 1. Default value is -1 which disables m2ts mode.
1058 @item muxrate @var{number}
1059 Set a constant muxrate (default VBR).
1060 @item pcr_period @var{numer}
1061 Override the default PCR retransmission time (default 20ms), ignored
1062 if variable muxrate is selected.
1063 @item pat_period @var{number}
1064 Maximal time in seconds between PAT/PMT tables.
1065 @item sdt_period @var{number}
1066 Maximal time in seconds between SDT tables.
1067 @item pes_payload_size @var{number}
1068 Set minimum PES packet payload in bytes.
1069 @item mpegts_flags @var{flags}
1070 Set flags (see below).
1071 @item mpegts_copyts @var{number}
1072 Preserve original timestamps, if value is set to 1. Default value is -1, which
1073 results in shifting timestamps so that they start from 0.
1074 @item tables_version @var{number}
1075 Set PAT, PMT and SDT version (default 0, valid values are from 0 to 31, inclusively).
1076 This option allows updating stream structure so that standard consumer may
1077 detect the change. To do so, reopen output AVFormatContext (in case of API
1078 usage) or restart ffmpeg instance, cyclically changing tables_version value:
1080 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1081 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1083 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1084 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1085 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1090 Option @option{mpegts_service_type} accepts the following values:
1094 Any hexdecimal value between 0x01 to 0xff as defined in ETSI 300 468.
1098 Digital Radio service.
1101 @item advanced_codec_digital_radio
1102 Advanced Codec Digital Radio service.
1103 @item mpeg2_digital_hdtv
1104 MPEG2 Digital HDTV service.
1105 @item advanced_codec_digital_sdtv
1106 Advanced Codec Digital SDTV service.
1107 @item advanced_codec_digital_hdtv
1108 Advanced Codec Digital HDTV service.
1111 Option @option{mpegts_flags} may take a set of such flags:
1114 @item resend_headers
1115 Reemit PAT/PMT before writing the next packet.
1117 Use LATM packetization for AAC.
1118 @item pat_pmt_at_frames
1119 Reemit PAT and PMT at each video frame.
1121 Conform to System B (DVB) instead of System A (ATSC).
1122 @item initial_discontinuity
1123 Mark the initial packet of each stream as discontinuity.
1129 ffmpeg -i file.mpg -c copy \
1130 -mpegts_original_network_id 0x1122 \
1131 -mpegts_transport_stream_id 0x3344 \
1132 -mpegts_service_id 0x5566 \
1133 -mpegts_pmt_start_pid 0x1500 \
1134 -mpegts_start_pid 0x150 \
1135 -metadata service_provider="Some provider" \
1136 -metadata service_name="Some Channel" \
1140 @section mxf, mxf_d10
1146 The muxer options are:
1149 @item store_user_comments @var{bool}
1150 Set if user comments should be stored if available or never.
1151 IRT D-10 does not allow user comments. The default is thus to write them for
1152 mxf but not for mxf_d10
1159 This muxer does not generate any output file, it is mainly useful for
1160 testing or benchmarking purposes.
1162 For example to benchmark decoding with @command{ffmpeg} you can use the
1165 ffmpeg -benchmark -i INPUT -f null out.null
1168 Note that the above command does not read or write the @file{out.null}
1169 file, but specifying the output file is required by the @command{ffmpeg}
1172 Alternatively you can write the command as:
1174 ffmpeg -benchmark -i INPUT -f null -
1180 @item -syncpoints @var{flags}
1181 Change the syncpoint usage in nut:
1183 @item @var{default} use the normal low-overhead seeking aids.
1184 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1185 Use of this option is not recommended, as the resulting files are very damage
1186 sensitive and seeking is not possible. Also in general the overhead from
1187 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1188 all growing data tables, allowing to mux endless streams with limited memory
1189 and without these disadvantages.
1190 @item @var{timestamped} extend the syncpoint with a wallclock field.
1192 The @var{none} and @var{timestamped} flags are experimental.
1193 @item -write_index @var{bool}
1194 Write index at the end, the default is to write an index.
1198 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1203 Ogg container muxer.
1206 @item -page_duration @var{duration}
1207 Preferred page duration, in microseconds. The muxer will attempt to create
1208 pages that are approximately @var{duration} microseconds long. This allows the
1209 user to compromise between seek granularity and container overhead. The default
1210 is 1 second. A value of 0 will fill all segments, making pages as large as
1211 possible. A value of 1 will effectively use 1 packet-per-page in most
1212 situations, giving a small seek granularity at the cost of additional container
1214 @item -serial_offset @var{value}
1215 Serial value from which to set the streams serial number.
1216 Setting it to different and sufficiently large values ensures that the produced
1217 ogg files can be safely chained.
1222 @section segment, stream_segment, ssegment
1224 Basic stream segmenter.
1226 This muxer outputs streams to a number of separate files of nearly
1227 fixed duration. Output filename pattern can be set in a fashion
1228 similar to @ref{image2}, or by using a @code{strftime} template if
1229 the @option{strftime} option is enabled.
1231 @code{stream_segment} is a variant of the muxer used to write to
1232 streaming output formats, i.e. which do not require global headers,
1233 and is recommended for outputting e.g. to MPEG transport stream segments.
1234 @code{ssegment} is a shorter alias for @code{stream_segment}.
1236 Every segment starts with a keyframe of the selected reference stream,
1237 which is set through the @option{reference_stream} option.
1239 Note that if you want accurate splitting for a video file, you need to
1240 make the input key frames correspond to the exact splitting times
1241 expected by the segmenter, or the segment muxer will start the new
1242 segment with the key frame found next after the specified start
1245 The segment muxer works best with a single constant frame rate video.
1247 Optionally it can generate a list of the created segments, by setting
1248 the option @var{segment_list}. The list type is specified by the
1249 @var{segment_list_type} option. The entry filenames in the segment
1250 list are set by default to the basename of the corresponding segment
1253 See also the @ref{hls} muxer, which provides a more specific
1254 implementation for HLS segmentation.
1258 The segment muxer supports the following options:
1261 @item increment_tc @var{1|0}
1262 if set to @code{1}, increment timecode between each segment
1263 If this is selected, the input need to have
1264 a timecode in the first video stream. Default value is
1267 @item reference_stream @var{specifier}
1268 Set the reference stream, as specified by the string @var{specifier}.
1269 If @var{specifier} is set to @code{auto}, the reference is chosen
1270 automatically. Otherwise it must be a stream specifier (see the ``Stream
1271 specifiers'' chapter in the ffmpeg manual) which specifies the
1272 reference stream. The default value is @code{auto}.
1274 @item segment_format @var{format}
1275 Override the inner container format, by default it is guessed by the filename
1278 @item segment_format_options @var{options_list}
1279 Set output format options using a :-separated list of key=value
1280 parameters. Values containing the @code{:} special character must be
1283 @item segment_list @var{name}
1284 Generate also a listfile named @var{name}. If not specified no
1285 listfile is generated.
1287 @item segment_list_flags @var{flags}
1288 Set flags affecting the segment list generation.
1290 It currently supports the following flags:
1293 Allow caching (only affects M3U8 list files).
1296 Allow live-friendly file generation.
1299 @item segment_list_size @var{size}
1300 Update the list file so that it contains at most @var{size}
1301 segments. If 0 the list file will contain all the segments. Default
1304 @item segment_list_entry_prefix @var{prefix}
1305 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1306 By default no prefix is applied.
1308 @item segment_list_type @var{type}
1309 Select the listing format.
1311 The following values are recognized:
1314 Generate a flat list for the created segments, one segment per line.
1317 Generate a list for the created segments, one segment per line,
1318 each line matching the format (comma-separated values):
1320 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1323 @var{segment_filename} is the name of the output file generated by the
1324 muxer according to the provided pattern. CSV escaping (according to
1325 RFC4180) is applied if required.
1327 @var{segment_start_time} and @var{segment_end_time} specify
1328 the segment start and end time expressed in seconds.
1330 A list file with the suffix @code{".csv"} or @code{".ext"} will
1331 auto-select this format.
1333 @samp{ext} is deprecated in favor or @samp{csv}.
1336 Generate an ffconcat file for the created segments. The resulting file
1337 can be read using the FFmpeg @ref{concat} demuxer.
1339 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1340 auto-select this format.
1343 Generate an extended M3U8 file, version 3, compliant with
1344 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1346 A list file with the suffix @code{".m3u8"} will auto-select this format.
1349 If not specified the type is guessed from the list file name suffix.
1351 @item segment_time @var{time}
1352 Set segment duration to @var{time}, the value must be a duration
1353 specification. Default value is "2". See also the
1354 @option{segment_times} option.
1356 Note that splitting may not be accurate, unless you force the
1357 reference stream key-frames at the given time. See the introductory
1358 notice and the examples below.
1360 @item segment_atclocktime @var{1|0}
1361 If set to "1" split at regular clock time intervals starting from 00:00
1362 o'clock. The @var{time} value specified in @option{segment_time} is
1363 used for setting the length of the splitting interval.
1365 For example with @option{segment_time} set to "900" this makes it possible
1366 to create files at 12:00 o'clock, 12:15, 12:30, etc.
1368 Default value is "0".
1370 @item segment_clocktime_offset @var{duration}
1371 Delay the segment splitting times with the specified duration when using
1372 @option{segment_atclocktime}.
1374 For example with @option{segment_time} set to "900" and
1375 @option{segment_clocktime_offset} set to "300" this makes it possible to
1376 create files at 12:05, 12:20, 12:35, etc.
1378 Default value is "0".
1380 @item segment_clocktime_wrap_duration @var{duration}
1381 Force the segmenter to only start a new segment if a packet reaches the muxer
1382 within the specified duration after the segmenting clock time. This way you
1383 can make the segmenter more resilient to backward local time jumps, such as
1384 leap seconds or transition to standard time from daylight savings time.
1386 Assuming that the delay between the packets of your source is less than 0.5
1387 second you can detect a leap second by specifying 0.5 as the duration.
1389 Default is the maximum possible duration which means starting a new segment
1390 regardless of the elapsed time since the last clock time.
1392 @item segment_time_delta @var{delta}
1393 Specify the accuracy time when selecting the start time for a
1394 segment, expressed as a duration specification. Default value is "0".
1396 When delta is specified a key-frame will start a new segment if its
1397 PTS satisfies the relation:
1399 PTS >= start_time - time_delta
1402 This option is useful when splitting video content, which is always
1403 split at GOP boundaries, in case a key frame is found just before the
1404 specified split time.
1406 In particular may be used in combination with the @file{ffmpeg} option
1407 @var{force_key_frames}. The key frame times specified by
1408 @var{force_key_frames} may not be set accurately because of rounding
1409 issues, with the consequence that a key frame time may result set just
1410 before the specified time. For constant frame rate videos a value of
1411 1/(2*@var{frame_rate}) should address the worst case mismatch between
1412 the specified time and the time set by @var{force_key_frames}.
1414 @item segment_times @var{times}
1415 Specify a list of split points. @var{times} contains a list of comma
1416 separated duration specifications, in increasing order. See also
1417 the @option{segment_time} option.
1419 @item segment_frames @var{frames}
1420 Specify a list of split video frame numbers. @var{frames} contains a
1421 list of comma separated integer numbers, in increasing order.
1423 This option specifies to start a new segment whenever a reference
1424 stream key frame is found and the sequential number (starting from 0)
1425 of the frame is greater or equal to the next value in the list.
1427 @item segment_wrap @var{limit}
1428 Wrap around segment index once it reaches @var{limit}.
1430 @item segment_start_number @var{number}
1431 Set the sequence number of the first segment. Defaults to @code{0}.
1433 @item strftime @var{1|0}
1434 Use the @code{strftime} function to define the name of the new
1435 segments to write. If this is selected, the output segment name must
1436 contain a @code{strftime} function template. Default value is
1439 @item break_non_keyframes @var{1|0}
1440 If enabled, allow segments to start on frames other than keyframes. This
1441 improves behavior on some players when the time between keyframes is
1442 inconsistent, but may make things worse on others, and can cause some oddities
1443 during seeking. Defaults to @code{0}.
1445 @item reset_timestamps @var{1|0}
1446 Reset timestamps at the begin of each segment, so that each segment
1447 will start with near-zero timestamps. It is meant to ease the playback
1448 of the generated segments. May not work with some combinations of
1449 muxers/codecs. It is set to @code{0} by default.
1451 @item initial_offset @var{offset}
1452 Specify timestamp offset to apply to the output packet timestamps. The
1453 argument must be a time duration specification, and defaults to 0.
1455 @item write_empty_segments @var{1|0}
1456 If enabled, write an empty segment if there are no packets during the period a
1457 segment would usually span. Otherwise, the segment will be filled with the next
1458 packet written. Defaults to @code{0}.
1461 @subsection Examples
1465 Remux the content of file @file{in.mkv} to a list of segments
1466 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
1467 generated segments to @file{out.list}:
1469 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.list out%03d.nut
1473 Segment input and set output format options for the output segments:
1475 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
1479 Segment the input file according to the split points specified by the
1480 @var{segment_times} option:
1482 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
1486 Use the @command{ffmpeg} @option{force_key_frames}
1487 option to force key frames in the input at the specified location, together
1488 with the segment option @option{segment_time_delta} to account for
1489 possible roundings operated when setting key frame times.
1491 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
1492 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
1494 In order to force key frames on the input file, transcoding is
1498 Segment the input file by splitting the input file according to the
1499 frame numbers sequence specified with the @option{segment_frames} option:
1501 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
1505 Convert the @file{in.mkv} to TS segments using the @code{libx264}
1506 and @code{aac} encoders:
1508 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
1512 Segment the input file, and create an M3U8 live playlist (can be used
1513 as live HLS source):
1515 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
1516 -segment_list_flags +live -segment_time 10 out%03d.mkv
1520 @section smoothstreaming
1522 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
1526 Specify the number of fragments kept in the manifest. Default 0 (keep all).
1528 @item extra_window_size
1529 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
1531 @item lookahead_count
1532 Specify the number of lookahead fragments. Default 2.
1534 @item min_frag_duration
1535 Specify the minimum fragment duration (in microseconds). Default 5000000.
1537 @item remove_at_exit
1538 Specify whether to remove all fragments when finished. Default 0 (do not remove).
1545 The fifo pseudo-muxer allows the separation of encoding and muxing by using
1546 first-in-first-out queue and running the actual muxer in a separate thread. This
1547 is especially useful in combination with the @ref{tee} muxer and can be used to
1548 send data to several destinations with different reliability/writing speed/latency.
1550 API users should be aware that callback functions (interrupt_callback,
1551 io_open and io_close) used within its AVFormatContext must be thread-safe.
1553 The behavior of the fifo muxer if the queue fills up or if the output fails is
1559 output can be transparently restarted with configurable delay between retries
1560 based on real time or time of the processed stream.
1563 encoding can be blocked during temporary failure, or continue transparently
1564 dropping packets in case fifo queue fills up.
1571 Specify the format name. Useful if it cannot be guessed from the
1575 Specify size of the queue (number of packets). Default value is 60.
1578 Specify format options for the underlying muxer. Muxer options can be specified
1579 as a list of @var{key}=@var{value} pairs separated by ':'.
1581 @item drop_pkts_on_overflow @var{bool}
1582 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
1583 rather than blocking the encoder. This makes it possible to continue streaming without
1584 delaying the input, at the cost of omitting part of the stream. By default
1585 this option is set to 0 (false), so in such cases the encoder will be blocked
1586 until the muxer processes some of the packets and none of them is lost.
1588 @item attempt_recovery @var{bool}
1589 If failure occurs, attempt to recover the output. This is especially useful
1590 when used with network output, since it makes it possible to restart streaming transparently.
1591 By default this option is set to 0 (false).
1593 @item max_recovery_attempts
1594 Sets maximum number of successive unsuccessful recovery attempts after which
1595 the output fails permanently. By default this option is set to 0 (unlimited).
1597 @item recovery_wait_time @var{duration}
1598 Waiting time before the next recovery attempt after previous unsuccessful
1599 recovery attempt. Default value is 5 seconds.
1601 @item recovery_wait_streamtime @var{bool}
1602 If set to 0 (false), the real time is used when waiting for the recovery
1603 attempt (i.e. the recovery will be attempted after at least
1604 recovery_wait_time seconds).
1605 If set to 1 (true), the time of the processed stream is taken into account
1606 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
1607 seconds of the stream is omitted).
1608 By default, this option is set to 0 (false).
1610 @item recover_any_error @var{bool}
1611 If set to 1 (true), recovery will be attempted regardless of type of the error
1612 causing the failure. By default this option is set to 0 (false) and in case of
1613 certain (usually permanent) errors the recovery is not attempted even when
1614 @var{attempt_recovery} is set to 1.
1616 @item restart_with_keyframe @var{bool}
1617 Specify whether to wait for the keyframe after recovering from
1618 queue overflow or failure. This option is set to 0 (false) by default.
1622 @subsection Examples
1627 Stream something to rtmp server, continue processing the stream at real-time
1628 rate even in case of temporary failure (network outage) and attempt to recover
1629 streaming every second indefinitely.
1631 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
1632 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
1640 The tee muxer can be used to write the same data to several files or any
1641 other kind of muxer. It can be used, for example, to both stream a video to
1642 the network and save it to disk at the same time.
1644 It is different from specifying several outputs to the @command{ffmpeg}
1645 command-line tool because the audio and video data will be encoded only once
1646 with the tee muxer; encoding can be a very expensive process. It is not
1647 useful when using the libavformat API directly because it is then possible
1648 to feed the same packets to several muxers directly.
1652 @item use_fifo @var{bool}
1653 If set to 1, slave outputs will be processed in separate thread using @ref{fifo}
1654 muxer. This allows to compensate for different speed/latency/reliability of
1655 outputs and setup transparent recovery. By default this feature is turned off.
1658 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
1662 The slave outputs are specified in the file name given to the muxer,
1663 separated by '|'. If any of the slave name contains the '|' separator,
1664 leading or trailing spaces or any special character, it must be
1665 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
1666 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
1668 Muxer options can be specified for each slave by prepending them as a list of
1669 @var{key}=@var{value} pairs separated by ':', between square brackets. If
1670 the options values contain a special character or the ':' separator, they
1671 must be escaped; note that this is a second level escaping.
1673 The following special options are also recognized:
1676 Specify the format name. Useful if it cannot be guessed from the
1679 @item bsfs[/@var{spec}]
1680 Specify a list of bitstream filters to apply to the specified
1683 @item use_fifo @var{bool}
1684 This allows to override tee muxer use_fifo option for individual slave muxer.
1687 This allows to override tee muxer fifo_options for individual slave muxer.
1690 It is possible to specify to which streams a given bitstream filter
1691 applies, by appending a stream specifier to the option separated by
1692 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
1693 stream specifiers}). If the stream specifier is not specified, the
1694 bitstream filters will be applied to all streams in the output.
1696 Several bitstream filters can be specified, separated by ",".
1699 Select the streams that should be mapped to the slave output,
1700 specified by a stream specifier. If not specified, this defaults to
1701 all the input streams. You may use multiple stream specifiers
1702 separated by commas (@code{,}) e.g.: @code{a:0,v}
1705 Specify behaviour on output failure. This can be set to either @code{abort} (which is
1706 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
1707 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
1708 will continue without being affected.
1711 @subsection Examples
1715 Encode something and both archive it in a WebM file and stream it
1716 as MPEG-TS over UDP (the streams need to be explicitly mapped):
1718 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
1719 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
1723 As above, but continue streaming even if output to local file fails
1724 (for example local drive fills up):
1726 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
1727 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
1731 Use @command{ffmpeg} to encode the input, and send the output
1732 to three different destinations. The @code{dump_extra} bitstream
1733 filter is used to add extradata information to all the output video
1734 keyframes packets, as requested by the MPEG-TS format. The select
1735 option is applied to @file{out.aac} in order to make it contain only
1738 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
1739 -f tee "[bsfs/v=dump_extra]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
1743 As below, but select only stream @code{a:1} for the audio output. Note
1744 that a second level escaping must be performed, as ":" is a special
1745 character used to separate options.
1747 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
1748 -f tee "[bsfs/v=dump_extra]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
1752 Note: some codecs may need different options depending on the output format;
1753 the auto-detection of this can not work with the tee muxer. The main example
1754 is the @option{global_header} flag.
1756 @section webm_dash_manifest
1758 WebM DASH Manifest muxer.
1760 This muxer implements the WebM DASH Manifest specification to generate the DASH
1761 manifest XML. It also supports manifest generation for DASH live streams.
1763 For more information see:
1767 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
1769 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
1774 This muxer supports the following options:
1777 @item adaptation_sets
1778 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
1779 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
1780 audio and video streams. Any number of adaptation sets can be added using this option.
1783 Set this to 1 to create a live stream DASH Manifest. Default: 0.
1785 @item chunk_start_index
1786 Start index of the first chunk. This will go in the @samp{startNumber} attribute
1787 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
1789 @item chunk_duration_ms
1790 Duration of each chunk in milliseconds. This will go in the @samp{duration}
1791 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
1793 @item utc_timing_url
1794 URL of the page that will return the UTC timestamp in ISO format. This will go
1795 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
1798 @item time_shift_buffer_depth
1799 Smallest time (in seconds) shifting buffer for which any Representation is
1800 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
1801 attribute of the @samp{MPD} element. Default: 60.
1803 @item minimum_update_period
1804 Minimum update period (in seconds) of the manifest. This will go in the
1805 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
1811 ffmpeg -f webm_dash_manifest -i video1.webm \
1812 -f webm_dash_manifest -i video2.webm \
1813 -f webm_dash_manifest -i audio1.webm \
1814 -f webm_dash_manifest -i audio2.webm \
1815 -map 0 -map 1 -map 2 -map 3 \
1817 -f webm_dash_manifest \
1818 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
1824 WebM Live Chunk Muxer.
1826 This muxer writes out WebM headers and chunks as separate files which can be
1827 consumed by clients that support WebM Live streams via DASH.
1831 This muxer supports the following options:
1834 @item chunk_start_index
1835 Index of the first chunk (defaults to 0).
1838 Filename of the header where the initialization data will be written.
1840 @item audio_chunk_duration
1841 Duration of each audio chunk in milliseconds (defaults to 5000).
1846 ffmpeg -f v4l2 -i /dev/video0 \
1850 -s 640x360 -keyint_min 30 -g 30 \
1852 -header webm_live_video_360.hdr \
1853 -chunk_start_index 1 \
1854 webm_live_video_360_%d.chk \
1859 -header webm_live_audio_128.hdr \
1860 -chunk_start_index 1 \
1861 -audio_chunk_duration 1000 \
1862 webm_live_audio_128_%d.chk