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,
100 which generates a fingerprint for the provided audio data. See @url{https://acoustid.org/chromaprint}
102 It takes a single signed native-endian 16-bit raw audio stream of at most 2 channels.
107 @item silence_threshold
108 Threshold for detecting silence, ranges from -1 to 32767. -1 disables silence detection and
109 is required for use with the AcoustID service. Default is -1.
112 Version of algorithm to fingerprint with. Range is 0 to 4. Version 2 requires that silence
113 detection be enabled. Default is 1.
116 Format to output the fingerprint as. Accepts the following options:
119 Binary raw fingerprint
122 Binary compressed fingerprint
125 Base64 compressed fingerprint @emph{(default)}
134 CRC (Cyclic Redundancy Check) testing format.
136 This muxer computes and prints the Adler-32 CRC of all the input audio
137 and video frames. By default audio frames are converted to signed
138 16-bit raw audio and video frames to raw video before computing the
141 The output of the muxer consists of a single line of the form:
142 CRC=0x@var{CRC}, where @var{CRC} is a hexadecimal number 0-padded to
143 8 digits containing the CRC for all the decoded input frames.
145 See also the @ref{framecrc} muxer.
149 For example to compute the CRC of the input, and store it in the file
152 ffmpeg -i INPUT -f crc out.crc
155 You can print the CRC to stdout with the command:
157 ffmpeg -i INPUT -f crc -
160 You can select the output format of each frame with @command{ffmpeg} by
161 specifying the audio and video codec and format. For example to
162 compute the CRC of the input audio converted to PCM unsigned 8-bit
163 and the input video converted to MPEG-2 video, use the command:
165 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f crc -
170 Adobe Flash Video Format muxer.
172 This muxer accepts the following options:
176 @item flvflags @var{flags}
181 @item aac_seq_header_detect
182 Place AAC sequence header based on audio stream data.
184 @item no_sequence_end
185 Disable sequence end tag.
188 Disable metadata tag.
190 @item no_duration_filesize
191 Disable duration and filesize in metadata when they are equal to zero
192 at the end of stream. (Be used to non-seekable living stream).
194 @item add_keyframe_index
195 Used to facilitate seeking; particularly for HTTP pseudo streaming.
202 Dynamic Adaptive Streaming over HTTP (DASH) muxer that creates segments
203 and manifest files according to the MPEG-DASH standard ISO/IEC 23009-1:2014.
205 For more information see:
209 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
211 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
214 It creates a MPD manifest file and segment files for each stream.
216 The segment filename might contain pre-defined identifiers used with SegmentTemplate
217 as defined in section 5.3.9.4.4 of the standard. Available identifiers are "$RepresentationID$",
218 "$Number$", "$Bandwidth$" and "$Time$".
219 In addition to the standard identifiers, an ffmpeg-specific "$ext$" identifier is also supported.
220 When specified ffmpeg will replace $ext$ in the file name with muxing format's extensions such as mp4, webm etc.,
223 ffmpeg -re -i <input> -map 0 -map 0 -c:a libfdk_aac -c:v libx264
224 -b:v:0 800k -b:v:1 300k -s:v:1 320x170 -profile:v:1 baseline
225 -profile:v:0 main -bf 1 -keyint_min 120 -g 120 -sc_threshold 0
226 -b_strategy 0 -ar:a:1 22050 -use_timeline 1 -use_template 1
227 -window_size 5 -adaptation_sets "id=0,streams=v id=1,streams=a"
228 -f dash /path/to/out.mpd
232 @item -min_seg_duration @var{microseconds}
233 This is a deprecated option to set the segment length in microseconds, use @var{seg_duration} instead.
234 @item -seg_duration @var{duration}
235 Set the segment length in seconds (fractional value can be set). The value is
236 treated as average segment duration when @var{use_template} is enabled and
237 @var{use_timeline} is disabled and as minimum segment duration for all the other
239 @item -window_size @var{size}
240 Set the maximum number of segments kept in the manifest.
241 @item -extra_window_size @var{size}
242 Set the maximum number of segments kept outside of the manifest before removing from disk.
243 @item -remove_at_exit @var{remove}
244 Enable (1) or disable (0) removal of all segments when finished.
245 @item -use_template @var{template}
246 Enable (1) or disable (0) use of SegmentTemplate instead of SegmentList.
247 @item -use_timeline @var{timeline}
248 Enable (1) or disable (0) use of SegmentTimeline in SegmentTemplate.
249 @item -single_file @var{single_file}
250 Enable (1) or disable (0) storing all segments in one file, accessed using byte ranges.
251 @item -single_file_name @var{file_name}
252 DASH-templated name to be used for baseURL. Implies @var{single_file} set to "1". In the template, "$ext$" is replaced with the file name extension specific for the segment format.
253 @item -init_seg_name @var{init_name}
254 DASH-templated name to used for the initialization segment. Default is "init-stream$RepresentationID$.$ext$". "$ext$" is replaced with the file name extension specific for the segment format.
255 @item -media_seg_name @var{segment_name}
256 DASH-templated name to used for the media segments. Default is "chunk-stream$RepresentationID$-$Number%05d$.$ext$". "$ext$" is replaced with the file name extension specific for the segment format.
257 @item -utc_timing_url @var{utc_url}
258 URL of the page that will return the UTC timestamp in ISO format. Example: "https://time.akamai.com/?iso"
259 @item method @var{method}
260 Use the given HTTP method to create output files. Generally set to PUT or POST.
261 @item -http_user_agent @var{user_agent}
262 Override User-Agent field in HTTP header. Applicable only for HTTP output.
263 @item -http_persistent @var{http_persistent}
264 Use persistent HTTP connections. Applicable only for HTTP output.
265 @item -hls_playlist @var{hls_playlist}
266 Generate HLS playlist files as well. The master playlist is generated with the filename master.m3u8.
267 One media playlist file is generated for each stream with filenames media_0.m3u8, media_1.m3u8, etc.
268 @item -streaming @var{streaming}
269 Enable (1) or disable (0) chunk streaming mode of output. In chunk streaming
270 mode, each frame will be a moof fragment which forms a chunk.
271 @item -adaptation_sets @var{adaptation_sets}
272 Assign streams to AdaptationSets. Syntax is "id=x,streams=a,b,c id=y,streams=d,e" with x and y being the IDs
273 of the adaptation sets and a,b,c,d and e are the indices of the mapped streams.
275 To map all video (or audio) streams to an AdaptationSet, "v" (or "a") can be used as stream identifier instead of IDs.
277 When no assignment is defined, this defaults to an AdaptationSet for each stream.
278 @item -timeout @var{timeout}
279 Set timeout for socket I/O operations. Applicable only for HTTP output.
280 @item -index_correction @var{index_correction}
281 Enable (1) or Disable (0) segment index correction logic. Applicable only when
282 @var{use_template} is enabled and @var{use_timeline} is disabled.
284 When enabled, the logic monitors the flow of segment indexes. If a streams's
285 segment index value is not at the expected real time position, then the logic
286 corrects that index value.
288 Typically this logic is needed in live streaming use cases. The network bandwidth
289 fluctuations are common during long run streaming. Each fluctuation can cause
290 the segment indexes fall behind the expected real time position.
291 @item -format_options @var{options_list}
292 Set container format (mp4/webm) options using a @code{:} separated list of
293 key=value parameters. Values containing @code{:} special characters must be
296 @item -dash_segment_type @var{dash_segment_type}
299 If this flag is set, the dash segment files format will be selected based on the stream codec. This is the default mode.
302 If this flag is set, the dash segment files will be in in ISOBMFF format.
305 If this flag is set, the dash segment files will be in in WebM format.
307 @item -ignore_io_errors @var{ignore_io_errors}
308 Ignore IO errors during open and write. Useful for long-duration runs with network output.
310 @item -lhls @var{lhls}
311 Enable Low-latency HLS(LHLS). Adds #EXT-X-PREFETCH tag with current segment's URI.
312 Apple doesn't have an official spec for LHLS. Meanwhile hls.js player folks are
313 trying to standardize a open LHLS spec. The draft spec is available in https://github.com/video-dev/hlsjs-rfcs/blob/lhls-spec/proposals/0001-lhls.md
314 This option will also try to comply with the above open spec, till Apple's spec officially supports it.
315 Applicable only when @var{streaming} and @var{hls_playlist} options are enabled.
316 This is an experimental feature.
323 Per-packet CRC (Cyclic Redundancy Check) testing format.
325 This muxer computes and prints the Adler-32 CRC for each audio
326 and video packet. By default audio frames are converted to signed
327 16-bit raw audio and video frames to raw video before computing the
330 The output of the muxer consists of a line for each audio and video
333 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
336 @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
341 For example to compute the CRC of the audio and video frames in
342 @file{INPUT}, converted to raw audio and video packets, and store it
343 in the file @file{out.crc}:
345 ffmpeg -i INPUT -f framecrc out.crc
348 To print the information to stdout, use the command:
350 ffmpeg -i INPUT -f framecrc -
353 With @command{ffmpeg}, you can select the output format to which the
354 audio and video frames are encoded before computing the CRC for each
355 packet by specifying the audio and video codec. For example, to
356 compute the CRC of each decoded input audio frame converted to PCM
357 unsigned 8-bit and of each decoded input video frame converted to
358 MPEG-2 video, use the command:
360 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
363 See also the @ref{crc} muxer.
368 Per-packet hash testing format.
370 This muxer computes and prints a cryptographic hash for each audio
371 and video packet. This can be used for packet-by-packet equality
372 checks without having to individually do a binary comparison on each.
374 By default audio frames are converted to signed 16-bit raw audio and
375 video frames to raw video before computing the hash, but the output
376 of explicit conversions to other codecs can also be used. It uses the
377 SHA-256 cryptographic hash function by default, but supports several
380 The output of the muxer consists of a line for each audio and video
383 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
386 @var{hash} is a hexadecimal number representing the computed hash
390 @item hash @var{algorithm}
391 Use the cryptographic hash function specified by the string @var{algorithm}.
392 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
393 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
394 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
395 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
401 To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
402 converted to raw audio and video packets, and store it in the file
405 ffmpeg -i INPUT -f framehash out.sha256
408 To print the information to stdout, using the MD5 hash function, use
411 ffmpeg -i INPUT -f framehash -hash md5 -
414 See also the @ref{hash} muxer.
419 Per-packet MD5 testing format.
421 This is a variant of the @ref{framehash} muxer. Unlike that muxer,
422 it defaults to using the MD5 hash function.
426 To compute the MD5 hash of the audio and video frames in @file{INPUT},
427 converted to raw audio and video packets, and store it in the file
430 ffmpeg -i INPUT -f framemd5 out.md5
433 To print the information to stdout, use the command:
435 ffmpeg -i INPUT -f framemd5 -
438 See also the @ref{framehash} and @ref{md5} muxers.
445 It accepts the following options:
449 Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
450 for looping indefinitely (default).
453 Force the delay (expressed in centiseconds) after the last frame. Each frame
454 ends with a delay until the next frame. The default is @code{-1}, which is a
455 special value to tell the muxer to re-use the previous delay. In case of a
456 loop, you might want to customize this value to mark a pause for instance.
459 For example, to encode a gif looping 10 times, with a 5 seconds delay between
462 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
465 Note 1: if you wish to extract the frames into separate GIF files, you need to
466 force the @ref{image2} muxer:
468 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
471 Note 2: the GIF format has a very large time base: the delay between two frames
472 can therefore not be smaller than one centi second.
479 This muxer computes and prints a cryptographic hash of all the input
480 audio and video frames. This can be used for equality checks without
481 having to do a complete binary comparison.
483 By default audio frames are converted to signed 16-bit raw audio and
484 video frames to raw video before computing the hash, but the output
485 of explicit conversions to other codecs can also be used. Timestamps
486 are ignored. It uses the SHA-256 cryptographic hash function by default,
487 but supports several other algorithms.
489 The output of the muxer consists of a single line of the form:
490 @var{algo}=@var{hash}, where @var{algo} is a short string representing
491 the hash function used, and @var{hash} is a hexadecimal number
492 representing the computed hash.
495 @item hash @var{algorithm}
496 Use the cryptographic hash function specified by the string @var{algorithm}.
497 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
498 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
499 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
500 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
506 To compute the SHA-256 hash of the input converted to raw audio and
507 video, and store it in the file @file{out.sha256}:
509 ffmpeg -i INPUT -f hash out.sha256
512 To print an MD5 hash to stdout use the command:
514 ffmpeg -i INPUT -f hash -hash md5 -
517 See also the @ref{framehash} muxer.
522 Apple HTTP Live Streaming muxer that segments MPEG-TS according to
523 the HTTP Live Streaming (HLS) specification.
525 It creates a playlist file, and one or more segment files. The output filename
526 specifies the playlist filename.
528 By default, the muxer creates a file for each segment produced. These files
529 have the same name as the playlist, followed by a sequential number and a
532 Make sure to require a closed GOP when encoding and to set the GOP
533 size to fit your segment time constraint.
535 For example, to convert an input file with @command{ffmpeg}:
537 ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
539 This example will produce the playlist, @file{out.m3u8}, and segment files:
540 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
542 See also the @ref{segment} muxer, which provides a more generic and
543 flexible implementation of a segmenter, and can be used to perform HLS
548 This muxer supports the following options:
551 @item hls_init_time @var{seconds}
552 Set the initial target segment length in seconds. Default value is @var{0}.
553 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
554 After the initial playlist is filled @command{ffmpeg} will cut segments
555 at duration equal to @code{hls_time}
557 @item hls_time @var{seconds}
558 Set the target segment length in seconds. Default value is 2.
559 Segment will be cut on the next key frame after this time has passed.
561 @item hls_list_size @var{size}
562 Set the maximum number of playlist entries. If set to 0 the list file
563 will contain all the segments. Default value is 5.
565 @item hls_delete_threshold @var{size}
566 Set the number of unreferenced segments to keep on disk before @code{hls_flags delete_segments}
567 deletes them. Increase this to allow continue clients to download segments which
568 were recently referenced in the playlist. Default value is 1, meaning segments older than
569 @code{hls_list_size+1} will be deleted.
571 @item hls_ts_options @var{options_list}
572 Set output format options using a :-separated list of key=value
573 parameters. Values containing @code{:} special characters must be
576 @item hls_wrap @var{wrap}
577 This is a deprecated option, you can use @code{hls_list_size}
578 and @code{hls_flags delete_segments} instead it
580 This option is useful to avoid to fill the disk with many segment
581 files, and limits the maximum number of segment files written to disk
585 @item hls_start_number_source
586 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
587 Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
588 segment and subtitle filenames. In any case, if @code{hls_flags append_list}
589 is set and read playlist sequence number is greater than the specified start sequence number,
590 then that value will be used as start value.
592 It accepts the following values:
596 @item generic (default)
597 Set the starting sequence numbers according to @var{start_number} option value.
600 The start number will be the seconds since epoch (1970-01-01 00:00:00)
603 The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
607 @item start_number @var{number}
608 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
609 when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
610 Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
613 @item hls_allow_cache @var{allowcache}
614 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
616 @item hls_base_url @var{baseurl}
617 Append @var{baseurl} to every entry in the playlist.
618 Useful to generate playlists with absolute paths.
620 Note that the playlist sequence number must be unique for each segment
621 and it is not to be confused with the segment filename sequence number
622 which can be cyclic, for example if the @option{wrap} option is
625 @item hls_segment_filename @var{filename}
626 Set the segment filename. Unless @code{hls_flags single_file} is set,
627 @var{filename} is used as a string format with the segment number:
629 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
631 This example will produce the playlist, @file{out.m3u8}, and segment files:
632 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
634 @var{filename} may contain full path or relative path specification,
635 but only the file name part without any path info will be contained in the m3u8 segment list.
636 Should a relative path be specified, the path of the created segment
637 files will be relative to the current working directory.
638 When strftime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
640 When @code{var_stream_map} is set with two or more variant streams, the
641 @var{filename} pattern must contain the string "%v", this string specifies
642 the position of variant stream index in the generated segment file names.
644 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
645 -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" \
646 -hls_segment_filename 'file_%v_%03d.ts' out_%v.m3u8
648 This example will produce the playlists segment file sets:
649 @file{file_0_000.ts}, @file{file_0_001.ts}, @file{file_0_002.ts}, etc. and
650 @file{file_1_000.ts}, @file{file_1_001.ts}, @file{file_1_002.ts}, etc.
652 The string "%v" may be present in the filename or in the last directory name
653 containing the file. If the string is present in the directory name, then
654 sub-directories are created after expanding the directory name pattern. This
655 enables creation of segments corresponding to different variant streams in
658 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
659 -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" \
660 -hls_segment_filename 'vs%v/file_%03d.ts' vs%v/out.m3u8
662 This example will produce the playlists segment file sets:
663 @file{vs0/file_000.ts}, @file{vs0/file_001.ts}, @file{vs0/file_002.ts}, etc. and
664 @file{vs1/file_000.ts}, @file{vs1/file_001.ts}, @file{vs1/file_002.ts}, etc.
667 Same as strftime option, will be deprecated.
670 Use strftime() on @var{filename} to expand the segment filename with localtime.
671 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
672 hls_flag and %%d will be the specifier.
674 ffmpeg -i in.nut -strftime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
676 This example will produce the playlist, @file{out.m3u8}, and segment files:
677 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
678 Note: On some systems/environments, the @code{%s} specifier is not available. See
679 @code{strftime()} documentation.
681 ffmpeg -i in.nut -strftime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
683 This example will produce the playlist, @file{out.m3u8}, and segment files:
684 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
686 @item use_localtime_mkdir
687 Same as strftime_mkdir option, will be deprecated .
690 Used together with -strftime_mkdir, it will create all subdirectories which
691 is expanded in @var{filename}.
693 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y%m%d/file-%Y%m%d-%s.ts' out.m3u8
695 This example will create a directory 201560215 (if it does not exist), and then
696 produce the playlist, @file{out.m3u8}, and segment files:
697 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
700 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y/%m/%d/file-%Y%m%d-%s.ts' out.m3u8
702 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
703 produce the playlist, @file{out.m3u8}, and segment files:
704 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
707 @item hls_key_info_file @var{key_info_file}
708 Use the information in @var{key_info_file} for segment encryption. The first
709 line of @var{key_info_file} specifies the key URI written to the playlist. The
710 key URL is used to access the encryption key during playback. The second line
711 specifies the path to the key file used to obtain the key during the encryption
712 process. The key file is read as a single packed array of 16 octets in binary
713 format. The optional third line specifies the initialization vector (IV) as a
714 hexadecimal string to be used instead of the segment sequence number (default)
715 for encryption. Changes to @var{key_info_file} will result in segment
716 encryption with the new key/IV and an entry in the playlist for the new key
717 URI/IV if @code{hls_flags periodic_rekey} is enabled.
719 Key info file format:
728 http://server/file.key
733 Example key file paths:
741 0123456789ABCDEF0123456789ABCDEF
744 Key info file example:
746 http://server/file.key
748 0123456789ABCDEF0123456789ABCDEF
751 Example shell script:
755 openssl rand 16 > file.key
756 echo $BASE_URL/file.key > file.keyinfo
757 echo file.key >> file.keyinfo
758 echo $(openssl rand -hex 16) >> file.keyinfo
759 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
760 -hls_key_info_file file.keyinfo out.m3u8
763 @item -hls_enc @var{enc}
764 Enable (1) or disable (0) the AES128 encryption.
765 When enabled every segment generated is encrypted and the encryption key
766 is saved as @var{playlist name}.key.
768 @item -hls_enc_key @var{key}
769 Hex-coded 16byte key to encrypt the segments, by default it
770 is randomly generated.
772 @item -hls_enc_key_url @var{keyurl}
773 If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
776 @item -hls_enc_iv @var{iv}
777 Hex-coded 16byte initialization vector for every segment instead
778 of the autogenerated ones.
780 @item hls_segment_type @var{flags}
785 Output segment files in MPEG-2 Transport Stream format. This is
786 compatible with all HLS versions.
789 Output segment files in fragmented MP4 format, similar to MPEG-DASH.
790 fmp4 files may be used in HLS version 7 and above.
794 @item hls_fmp4_init_filename @var{filename}
795 Set filename to the fragment files header file, default filename is @file{init.mp4}.
797 When @code{var_stream_map} is set with two or more variant streams, the
798 @var{filename} pattern must contain the string "%v", this string specifies
799 the position of variant stream index in the generated init file names.
800 The string "%v" may be present in the filename or in the last directory name
801 containing the file. If the string is present in the directory name, then
802 sub-directories are created after expanding the directory name pattern. This
803 enables creation of init files corresponding to different variant streams in
806 @item hls_flags @var{flags}
811 If this flag is set, the muxer will store all segments in a single MPEG-TS
812 file, and will use byte ranges in the playlist. HLS playlists generated with
813 this way will have the version number 4.
816 ffmpeg -i in.nut -hls_flags single_file out.m3u8
818 Will produce the playlist, @file{out.m3u8}, and a single segment file,
821 @item delete_segments
822 Segment files removed from the playlist are deleted after a period of time
823 equal to the duration of the segment plus the duration of the playlist.
826 Append new segments into the end of old segment list,
827 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
829 @item round_durations
830 Round the duration info in the playlist file segment info to integer
831 values, instead of using floating point.
834 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
835 first segment's information.
838 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
841 The file specified by @code{hls_key_info_file} will be checked periodically and
842 detect updates to the encryption info. Be sure to replace this file atomically,
843 including the file containing the AES encryption key.
845 @item independent_segments
846 Add the @code{#EXT-X-INDEPENDENT-SEGMENTS} to playlists that has video segments
847 and when all the segments of that playlist are guaranteed to start with a Key frame.
850 Allow segments to start on frames other than keyframes. This improves
851 behavior on some players when the time between keyframes is inconsistent,
852 but may make things worse on others, and can cause some oddities during
853 seeking. This flag should be used with the @code{hls_time} option.
855 @item program_date_time
856 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
858 @item second_level_segment_index
859 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
860 besides date/time values when strftime is on.
861 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
863 @item second_level_segment_size
864 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
865 expression besides date/time values when strftime is on.
866 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
868 @item second_level_segment_duration
869 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
870 expression besides date/time values when strftime is on.
871 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
874 ffmpeg -i sample.mpeg \
875 -f hls -hls_time 3 -hls_list_size 5 \
876 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
877 -strftime 1 -strftime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
879 This will produce segments like this:
880 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
883 Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
884 serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
885 before they have been added to the m3u8 playlist.
889 @item hls_playlist_type event
890 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
891 @option{hls_list_size} to 0; the playlist can only be appended to.
893 @item hls_playlist_type vod
894 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
895 @option{hls_list_size} to 0; the playlist must not change.
898 Use the given HTTP method to create the hls files.
900 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
902 This example will upload all the mpegts segment files to the HTTP
903 server using the HTTP PUT method, and update the m3u8 files every
904 @code{refresh} times using the same method.
905 Note that the HTTP server must support the given method for uploading
908 @item http_user_agent
909 Override User-Agent field in HTTP header. Applicable only for HTTP output.
912 Map string which specifies how to group the audio, video and subtitle streams
913 into different variant streams. The variant stream groups are separated
915 Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
916 the keys to specify audio, video and subtitle streams respectively.
917 Allowed values are 0 to 9 (limited just based on practical usage).
919 When there are two or more variant streams, the output filename pattern must
920 contain the string "%v", this string specifies the position of variant stream
921 index in the output media playlist filenames. The string "%v" may be present in
922 the filename or in the last directory name containing the file. If the string is
923 present in the directory name, then sub-directories are created after expanding
924 the directory name pattern. This enables creation of variant streams in
928 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
929 -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" \
930 http://example.com/live/out_%v.m3u8
932 This example creates two hls variant streams. The first variant stream will
933 contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
934 second variant stream will contain video stream of bitrate 256k and audio
935 stream of bitrate 32k. Here, two media playlist with file names out_0.m3u8 and
936 out_1.m3u8 will be created.
938 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
939 -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
940 http://example.com/live/out_%v.m3u8
942 This example creates three hls variant streams. The first variant stream will
943 be a video only stream with video bitrate 1000k, the second variant stream will
944 be an audio only stream with bitrate 64k and the third variant stream will be a
945 video only stream with bitrate 256k. Here, three media playlist with file names
946 out_0.m3u8, out_1.m3u8 and out_2.m3u8 will be created.
948 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
949 -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" \
950 http://example.com/live/vs_%v/out.m3u8
952 This example creates the variant streams in subdirectories. Here, the first
953 media playlist is created at @file{http://example.com/live/vs_0/out.m3u8} and
954 the second one at @file{http://example.com/live/vs_1/out.m3u8}.
956 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k \
957 -map 0:a -map 0:a -map 0:v -map 0:v -f hls \
958 -var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
959 -master_pl_name master.m3u8 \
960 http://example.com/live/out_%v.m3u8
962 This example creates two audio only and two video only variant streams. In
963 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
964 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
965 and they are mapped to the two video only variant streams with audio group names
966 'aud_low' and 'aud_high'.
968 By default, a single hls variant containing all the encoded streams is created.
971 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
972 -map 0:a -map 0:a -map 0:v -f hls \
973 -var_stream_map "a:0,agroup:aud_low,default:yes a:1,agroup:aud_low v:0,agroup:aud_low" \
974 -master_pl_name master.m3u8 \
975 http://example.com/live/out_%v.m3u8
977 This example creates two audio only and one video only variant streams. In
978 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
979 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
980 and they are mapped to the one video only variant streams with audio group name
981 'aud_low', and the audio group have default stat is NO or YES.
983 By default, a single hls variant containing all the encoded streams is created.
986 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
987 -map 0:a -map 0:a -map 0:v -f hls \
988 -var_stream_map "a:0,agroup:aud_low,default:yes,language=ENG a:1,agroup:aud_low,language:CHN v:0,agroup:aud_low" \
989 -master_pl_name master.m3u8 \
990 http://example.com/live/out_%v.m3u8
992 This example creates two audio only and one video only variant streams. In
993 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
994 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
995 and they are mapped to the one video only variant streams with audio group name
996 'aud_low', and the audio group have default stat is NO or YES, and one audio
997 have and language is named ENG, the other audio language is named CHN.
999 By default, a single hls variant containing all the encoded streams is created.
1002 Map string which specifies different closed captions groups and their
1003 attributes. The closed captions stream groups are separated by space.
1004 Expected string format is like this
1005 "ccgroup:<group name>,instreamid:<INSTREAM-ID>,language:<language code> ....".
1006 'ccgroup' and 'instreamid' are mandatory attributes. 'language' is an optional
1008 The closed captions groups configured using this option are mapped to different
1009 variant streams by providing the same 'ccgroup' name in the
1010 @code{var_stream_map} string. If @code{var_stream_map} is not set, then the
1011 first available ccgroup in @code{cc_stream_map} is mapped to the output variant
1012 stream. The examples for these two use cases are given below.
1015 ffmpeg -re -i in.ts -b:v 1000k -b:a 64k -a53cc 1 -f hls \
1016 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en" \
1017 -master_pl_name master.m3u8 \
1018 http://example.com/live/out.m3u8
1020 This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=CLOSED-CAPTIONS} in
1021 the master playlist with group name 'cc', language 'en' (english) and
1022 INSTREAM-ID 'CC1'. Also, it adds @code{CLOSED-CAPTIONS} attribute with group
1023 name 'cc' for the output variant stream.
1025 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1026 -a53cc:0 1 -a53cc:1 1\
1027 -map 0:v -map 0:a -map 0:v -map 0:a -f hls \
1028 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en ccgroup:cc,instreamid:CC2,language:sp" \
1029 -var_stream_map "v:0,a:0,ccgroup:cc v:1,a:1,ccgroup:cc" \
1030 -master_pl_name master.m3u8 \
1031 http://example.com/live/out_%v.m3u8
1033 This example adds two @code{#EXT-X-MEDIA} tags with @code{TYPE=CLOSED-CAPTIONS} in
1034 the master playlist for the INSTREAM-IDs 'CC1' and 'CC2'. Also, it adds
1035 @code{CLOSED-CAPTIONS} attribute with group name 'cc' for the two output variant
1038 @item master_pl_name
1039 Create HLS master playlist with the given name.
1042 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
1044 This example creates HLS master playlist with name master.m3u8 and it is
1045 published at http://example.com/live/
1047 @item master_pl_publish_rate
1048 Publish master play list repeatedly every after specified number of segment intervals.
1051 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
1052 -hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
1055 This example creates HLS master playlist with name master.m3u8 and keep
1056 publishing it repeatedly every after 30 segments i.e. every after 60s.
1058 @item http_persistent
1059 Use persistent HTTP connections. Applicable only for HTTP output.
1062 Set timeout for socket I/O operations. Applicable only for HTTP output.
1064 @item -ignore_io_errors
1065 Ignore IO errors during open, write and delete. Useful for long-duration runs with network output.
1074 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
1078 Size cannot exceed 256 pixels in any dimension
1081 Only BMP and PNG images can be stored
1084 If a BMP image is used, it must be one of the following pixel formats:
1086 BMP Bit Depth FFmpeg Pixel Format
1096 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
1099 If a PNG image is used, it must use the rgba pixel format
1107 The image file muxer writes video frames to image files.
1109 The output filenames are specified by a pattern, which can be used to
1110 produce sequentially numbered series of files.
1111 The pattern may contain the string "%d" or "%0@var{N}d", this string
1112 specifies the position of the characters representing a numbering in
1113 the filenames. If the form "%0@var{N}d" is used, the string
1114 representing the number in each filename is 0-padded to @var{N}
1115 digits. The literal character '%' can be specified in the pattern with
1118 If the pattern contains "%d" or "%0@var{N}d", the first filename of
1119 the file list specified will contain the number 1, all the following
1120 numbers will be sequential.
1122 The pattern may contain a suffix which is used to automatically
1123 determine the format of the image files to write.
1125 For example the pattern "img-%03d.bmp" will specify a sequence of
1126 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
1127 @file{img-010.bmp}, etc.
1128 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
1129 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
1132 @subsection Examples
1134 The following example shows how to use @command{ffmpeg} for creating a
1135 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
1136 taking one image every second from the input video:
1138 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
1141 Note that with @command{ffmpeg}, if the format is not specified with the
1142 @code{-f} option and the output filename specifies an image file
1143 format, the image2 muxer is automatically selected, so the previous
1144 command can be written as:
1146 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
1149 Note also that the pattern must not necessarily contain "%d" or
1150 "%0@var{N}d", for example to create a single image file
1151 @file{img.jpeg} from the start of the input video you can employ the command:
1153 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
1156 The @option{strftime} option allows you to expand the filename with
1157 date and time information. Check the documentation of
1158 the @code{strftime()} function for the syntax.
1160 For example to generate image files from the @code{strftime()}
1161 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
1164 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
1167 You can set the file name with current frame's PTS:
1169 ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
1176 If set to 1, expand the filename with pts from pkt->pts.
1180 Start the sequence from the specified number. Default value is 1.
1183 If set to 1, the filename will always be interpreted as just a
1184 filename, not a pattern, and the corresponding file will be continuously
1185 overwritten with new images. Default value is 0.
1188 If set to 1, expand the filename with date and time information from
1189 @code{strftime()}. Default value is 0.
1192 The image muxer supports the .Y.U.V image file format. This format is
1193 special in that that each image frame consists of three files, for
1194 each of the YUV420P components. To read or write this image file format,
1195 specify the name of the '.Y' file. The muxer will automatically open the
1196 '.U' and '.V' files as required.
1200 Matroska container muxer.
1202 This muxer implements the matroska and webm container specs.
1204 @subsection Metadata
1206 The recognized metadata settings in this muxer are:
1210 Set title name provided to a single track.
1213 Specify the language of the track in the Matroska languages form.
1215 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
1216 639-2/B) form (like "fre" for French), or a language code mixed with a
1217 country code for specialities in languages (like "fre-ca" for Canadian
1221 Set stereo 3D video layout of two views in a single video track.
1223 The following values are recognized:
1228 Both views are arranged side by side, Left-eye view is on the left
1230 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
1232 Both views are arranged in top-bottom orientation, Left-eye view is on top
1233 @item checkerboard_rl
1234 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
1235 @item checkerboard_lr
1236 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
1237 @item row_interleaved_rl
1238 Each view is constituted by a row based interleaving, Right-eye view is first row
1239 @item row_interleaved_lr
1240 Each view is constituted by a row based interleaving, Left-eye view is first row
1241 @item col_interleaved_rl
1242 Both views are arranged in a column based interleaving manner, Right-eye view is first column
1243 @item col_interleaved_lr
1244 Both views are arranged in a column based interleaving manner, Left-eye view is first column
1245 @item anaglyph_cyan_red
1246 All frames are in anaglyph format viewable through red-cyan filters
1248 Both views are arranged side by side, Right-eye view is on the left
1249 @item anaglyph_green_magenta
1250 All frames are in anaglyph format viewable through green-magenta filters
1252 Both eyes laced in one Block, Left-eye view is first
1254 Both eyes laced in one Block, Right-eye view is first
1258 For example a 3D WebM clip can be created using the following command line:
1260 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
1265 This muxer supports the following options:
1268 @item reserve_index_space
1269 By default, this muxer writes the index for seeking (called cues in Matroska
1270 terms) at the end of the file, because it cannot know in advance how much space
1271 to leave for the index at the beginning of the file. However for some use cases
1272 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
1273 index at the beginning of the file.
1275 If this option is set to a non-zero value, the muxer will reserve a given amount
1276 of space in the file header and then try to write the cues there when the muxing
1277 finishes. If the available space does not suffice, muxing will fail. A safe size
1278 for most use cases should be about 50kB per hour of video.
1280 Note that cues are only written if the output is seekable and this option will
1281 have no effect if it is not.
1289 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
1290 defaults to using the MD5 hash function.
1292 @subsection Examples
1294 To compute the MD5 hash of the input converted to raw
1295 audio and video, and store it in the file @file{out.md5}:
1297 ffmpeg -i INPUT -f md5 out.md5
1300 You can print the MD5 to stdout with the command:
1302 ffmpeg -i INPUT -f md5 -
1305 See also the @ref{hash} and @ref{framemd5} muxers.
1307 @section mov, mp4, ismv
1309 MOV/MP4/ISMV (Smooth Streaming) muxer.
1311 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
1312 file has all the metadata about all packets stored in one location
1313 (written at the end of the file, it can be moved to the start for
1314 better playback by adding @var{faststart} to the @var{movflags}, or
1315 using the @command{qt-faststart} tool). A fragmented
1316 file consists of a number of fragments, where packets and metadata
1317 about these packets are stored together. Writing a fragmented
1318 file has the advantage that the file is decodable even if the
1319 writing is interrupted (while a normal MOV/MP4 is undecodable if
1320 it is not properly finished), and it requires less memory when writing
1321 very long files (since writing normal MOV/MP4 files stores info about
1322 every single packet in memory until the file is closed). The downside
1323 is that it is less compatible with other applications.
1327 Fragmentation is enabled by setting one of the AVOptions that define
1328 how to cut the file into fragments:
1331 @item -moov_size @var{bytes}
1332 Reserves space for the moov atom at the beginning of the file instead of placing the
1333 moov atom at the end. If the space reserved is insufficient, muxing will fail.
1334 @item -movflags frag_keyframe
1335 Start a new fragment at each video keyframe.
1336 @item -frag_duration @var{duration}
1337 Create fragments that are @var{duration} microseconds long.
1338 @item -frag_size @var{size}
1339 Create fragments that contain up to @var{size} bytes of payload data.
1340 @item -movflags frag_custom
1341 Allow the caller to manually choose when to cut fragments, by
1342 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
1343 the packets written so far. (This is only useful with other
1344 applications integrating libavformat, not from @command{ffmpeg}.)
1345 @item -min_frag_duration @var{duration}
1346 Don't create fragments that are shorter than @var{duration} microseconds long.
1349 If more than one condition is specified, fragments are cut when
1350 one of the specified conditions is fulfilled. The exception to this is
1351 @code{-min_frag_duration}, which has to be fulfilled for any of the other
1352 conditions to apply.
1354 Additionally, the way the output file is written can be adjusted
1355 through a few other options:
1358 @item -movflags empty_moov
1359 Write an initial moov atom directly at the start of the file, without
1360 describing any samples in it. Generally, an mdat/moov pair is written
1361 at the start of the file, as a normal MOV/MP4 file, containing only
1362 a short portion of the file. With this option set, there is no initial
1363 mdat atom, and the moov atom only describes the tracks but has
1366 This option is implicitly set when writing ismv (Smooth Streaming) files.
1367 @item -movflags separate_moof
1368 Write a separate moof (movie fragment) atom for each track. Normally,
1369 packets for all tracks are written in a moof atom (which is slightly
1370 more efficient), but with this option set, the muxer writes one moof/mdat
1371 pair for each track, making it easier to separate tracks.
1373 This option is implicitly set when writing ismv (Smooth Streaming) files.
1374 @item -movflags skip_sidx
1375 Skip writing of sidx atom. When bitrate overhead due to sidx atom is high,
1376 this option could be used for cases where sidx atom is not mandatory.
1377 When global_sidx flag is enabled, this option will be ignored.
1378 @item -movflags faststart
1379 Run a second pass moving the index (moov atom) to the beginning of the file.
1380 This operation can take a while, and will not work in various situations such
1381 as fragmented output, thus it is not enabled by default.
1382 @item -movflags rtphint
1383 Add RTP hinting tracks to the output file.
1384 @item -movflags disable_chpl
1385 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
1386 and a QuickTime chapter track are written to the file. With this option
1387 set, only the QuickTime chapter track will be written. Nero chapters can
1388 cause failures when the file is reprocessed with certain tagging programs, like
1389 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
1390 @item -movflags omit_tfhd_offset
1391 Do not write any absolute base_data_offset in tfhd atoms. This avoids
1392 tying fragments to absolute byte positions in the file/streams.
1393 @item -movflags default_base_moof
1394 Similarly to the omit_tfhd_offset, this flag avoids writing the
1395 absolute base_data_offset field in tfhd atoms, but does so by using
1396 the new default-base-is-moof flag instead. This flag is new from
1397 14496-12:2012. This may make the fragments easier to parse in certain
1398 circumstances (avoiding basing track fragment location calculations
1399 on the implicit end of the previous track fragment).
1401 Specify @code{on} to force writing a timecode track, @code{off} to disable it
1402 and @code{auto} to write a timecode track only for mov and mp4 output (default).
1403 @item -movflags negative_cts_offsets
1404 Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
1405 be negative. This enables the initial sample to have DTS/CTS of zero, and
1406 reduces the need for edit lists for some cases such as video tracks with
1407 B-frames. Additionally, eases conformance with the DASH-IF interoperability
1410 This option is implicitly set when writing ismv (Smooth Streaming) files.
1412 Write producer time reference box (PRFT) with a specified time source for the
1413 NTP field in the PRFT box. Set value as @samp{wallclock} to specify timesource
1414 as wallclock time and @samp{pts} to specify timesource as input packets' PTS
1417 Setting value to @samp{pts} is applicable only for a live encoding use case,
1418 where PTS values are set as as wallclock time at the source. For example, an
1419 encoding use case with decklink capture source where @option{video_pts} and
1420 @option{audio_pts} are set to @samp{abs_wallclock}.
1425 Smooth Streaming content can be pushed in real time to a publishing
1426 point on IIS with this muxer. Example:
1428 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
1431 @subsection Audible AAX
1433 Audible AAX files are encrypted M4B files, and they can be decrypted by specifying a 4 byte activation secret.
1435 ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
1440 The MP3 muxer writes a raw MP3 stream with the following optional features:
1443 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
1444 2.4 are supported, the @code{id3v2_version} private option controls which one is
1445 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
1448 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
1449 The pictures are supplied to the muxer in form of a video stream with a single
1450 packet. There can be any number of those streams, each will correspond to a
1451 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
1452 to APIC @var{description} and @var{picture type} respectively. See
1453 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
1455 Note that the APIC frames must be written at the beginning, so the muxer will
1456 buffer the audio frames until it gets all the pictures. It is therefore advised
1457 to provide the pictures as soon as possible to avoid excessive buffering.
1460 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
1461 default, but will be written only if the output is seekable. The
1462 @code{write_xing} private option can be used to disable it. The frame contains
1463 various information that may be useful to the decoder, like the audio duration
1467 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1468 enabled with the @code{write_id3v1} private option, but as its capabilities are
1469 very limited, its usage is not recommended.
1474 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1476 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1479 To attach a picture to an mp3 file select both the audio and the picture stream
1482 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1483 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1486 Write a "clean" MP3 without any extra features:
1488 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1493 MPEG transport stream muxer.
1495 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1497 The recognized metadata settings in mpegts muxer are @code{service_provider}
1498 and @code{service_name}. If they are not set the default for
1499 @code{service_provider} is @samp{FFmpeg} and the default for
1500 @code{service_name} is @samp{Service01}.
1504 The muxer options are:
1507 @item mpegts_transport_stream_id @var{integer}
1508 Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
1509 Default is @code{0x0001}.
1511 @item mpegts_original_network_id @var{integer}
1512 Set the @samp{original_network_id}. This is unique identifier of a
1513 network in DVB. Its main use is in the unique identification of a service
1514 through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
1517 @item mpegts_service_id @var{integer}
1518 Set the @samp{service_id}, also known as program in DVB. Default is
1521 @item mpegts_service_type @var{integer}
1522 Set the program @samp{service_type}. Default is @code{digital_tv}.
1523 Accepts the following options:
1526 Any hexadecimal value between @code{0x01} and @code{0xff} as defined in
1531 Digital Radio service.
1534 @item advanced_codec_digital_radio
1535 Advanced Codec Digital Radio service.
1536 @item mpeg2_digital_hdtv
1537 MPEG2 Digital HDTV service.
1538 @item advanced_codec_digital_sdtv
1539 Advanced Codec Digital SDTV service.
1540 @item advanced_codec_digital_hdtv
1541 Advanced Codec Digital HDTV service.
1544 @item mpegts_pmt_start_pid @var{integer}
1545 Set the first PID for PMT. Default is @code{0x1000}. Max is @code{0x1f00}.
1547 @item mpegts_start_pid @var{integer}
1548 Set the first PID for data packets. Default is @code{0x0100}. Max is
1551 @item mpegts_m2ts_mode @var{boolean}
1552 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
1555 @item muxrate @var{integer}
1556 Set a constant muxrate. Default is VBR.
1558 @item pes_payload_size @var{integer}
1559 Set minimum PES packet payload in bytes. Default is @code{2930}.
1561 @item mpegts_flags @var{flags}
1562 Set mpegts flags. Accepts the following options:
1564 @item resend_headers
1565 Reemit PAT/PMT before writing the next packet.
1567 Use LATM packetization for AAC.
1568 @item pat_pmt_at_frames
1569 Reemit PAT and PMT at each video frame.
1571 Conform to System B (DVB) instead of System A (ATSC).
1572 @item initial_discontinuity
1573 Mark the initial packet of each stream as discontinuity.
1576 @item resend_headers @var{integer}
1577 Reemit PAT/PMT before writing the next packet. This option is deprecated:
1578 use @option{mpegts_flags} instead.
1580 @item mpegts_copyts @var{boolean}
1581 Preserve original timestamps, if value is set to @code{1}. Default value
1582 is @code{-1}, which results in shifting timestamps so that they start from 0.
1584 @item omit_video_pes_length @var{boolean}
1585 Omit the PES packet length for video packets. Default is @code{1} (true).
1587 @item pcr_period @var{integer}
1588 Override the default PCR retransmission time in milliseconds. Ignored if
1589 variable muxrate is selected. Default is @code{20}.
1591 @item pat_period @var{double}
1592 Maximum time in seconds between PAT/PMT tables.
1594 @item sdt_period @var{double}
1595 Maximum time in seconds between SDT tables.
1597 @item tables_version @var{integer}
1598 Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
1599 This option allows updating stream structure so that standard consumer may
1600 detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
1601 usage) or restart @command{ffmpeg} instance, cyclically changing
1602 @option{tables_version} value:
1605 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1606 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1608 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1609 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1610 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1618 ffmpeg -i file.mpg -c copy \
1619 -mpegts_original_network_id 0x1122 \
1620 -mpegts_transport_stream_id 0x3344 \
1621 -mpegts_service_id 0x5566 \
1622 -mpegts_pmt_start_pid 0x1500 \
1623 -mpegts_start_pid 0x150 \
1624 -metadata service_provider="Some provider" \
1625 -metadata service_name="Some Channel" \
1629 @section mxf, mxf_d10
1635 The muxer options are:
1638 @item store_user_comments @var{bool}
1639 Set if user comments should be stored if available or never.
1640 IRT D-10 does not allow user comments. The default is thus to write them for
1641 mxf but not for mxf_d10
1648 This muxer does not generate any output file, it is mainly useful for
1649 testing or benchmarking purposes.
1651 For example to benchmark decoding with @command{ffmpeg} you can use the
1654 ffmpeg -benchmark -i INPUT -f null out.null
1657 Note that the above command does not read or write the @file{out.null}
1658 file, but specifying the output file is required by the @command{ffmpeg}
1661 Alternatively you can write the command as:
1663 ffmpeg -benchmark -i INPUT -f null -
1669 @item -syncpoints @var{flags}
1670 Change the syncpoint usage in nut:
1672 @item @var{default} use the normal low-overhead seeking aids.
1673 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1674 Use of this option is not recommended, as the resulting files are very damage
1675 sensitive and seeking is not possible. Also in general the overhead from
1676 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1677 all growing data tables, allowing to mux endless streams with limited memory
1678 and without these disadvantages.
1679 @item @var{timestamped} extend the syncpoint with a wallclock field.
1681 The @var{none} and @var{timestamped} flags are experimental.
1682 @item -write_index @var{bool}
1683 Write index at the end, the default is to write an index.
1687 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1692 Ogg container muxer.
1695 @item -page_duration @var{duration}
1696 Preferred page duration, in microseconds. The muxer will attempt to create
1697 pages that are approximately @var{duration} microseconds long. This allows the
1698 user to compromise between seek granularity and container overhead. The default
1699 is 1 second. A value of 0 will fill all segments, making pages as large as
1700 possible. A value of 1 will effectively use 1 packet-per-page in most
1701 situations, giving a small seek granularity at the cost of additional container
1703 @item -serial_offset @var{value}
1704 Serial value from which to set the streams serial number.
1705 Setting it to different and sufficiently large values ensures that the produced
1706 ogg files can be safely chained.
1711 @section segment, stream_segment, ssegment
1713 Basic stream segmenter.
1715 This muxer outputs streams to a number of separate files of nearly
1716 fixed duration. Output filename pattern can be set in a fashion
1717 similar to @ref{image2}, or by using a @code{strftime} template if
1718 the @option{strftime} option is enabled.
1720 @code{stream_segment} is a variant of the muxer used to write to
1721 streaming output formats, i.e. which do not require global headers,
1722 and is recommended for outputting e.g. to MPEG transport stream segments.
1723 @code{ssegment} is a shorter alias for @code{stream_segment}.
1725 Every segment starts with a keyframe of the selected reference stream,
1726 which is set through the @option{reference_stream} option.
1728 Note that if you want accurate splitting for a video file, you need to
1729 make the input key frames correspond to the exact splitting times
1730 expected by the segmenter, or the segment muxer will start the new
1731 segment with the key frame found next after the specified start
1734 The segment muxer works best with a single constant frame rate video.
1736 Optionally it can generate a list of the created segments, by setting
1737 the option @var{segment_list}. The list type is specified by the
1738 @var{segment_list_type} option. The entry filenames in the segment
1739 list are set by default to the basename of the corresponding segment
1742 See also the @ref{hls} muxer, which provides a more specific
1743 implementation for HLS segmentation.
1747 The segment muxer supports the following options:
1750 @item increment_tc @var{1|0}
1751 if set to @code{1}, increment timecode between each segment
1752 If this is selected, the input need to have
1753 a timecode in the first video stream. Default value is
1756 @item reference_stream @var{specifier}
1757 Set the reference stream, as specified by the string @var{specifier}.
1758 If @var{specifier} is set to @code{auto}, the reference is chosen
1759 automatically. Otherwise it must be a stream specifier (see the ``Stream
1760 specifiers'' chapter in the ffmpeg manual) which specifies the
1761 reference stream. The default value is @code{auto}.
1763 @item segment_format @var{format}
1764 Override the inner container format, by default it is guessed by the filename
1767 @item segment_format_options @var{options_list}
1768 Set output format options using a :-separated list of key=value
1769 parameters. Values containing the @code{:} special character must be
1772 @item segment_list @var{name}
1773 Generate also a listfile named @var{name}. If not specified no
1774 listfile is generated.
1776 @item segment_list_flags @var{flags}
1777 Set flags affecting the segment list generation.
1779 It currently supports the following flags:
1782 Allow caching (only affects M3U8 list files).
1785 Allow live-friendly file generation.
1788 @item segment_list_size @var{size}
1789 Update the list file so that it contains at most @var{size}
1790 segments. If 0 the list file will contain all the segments. Default
1793 @item segment_list_entry_prefix @var{prefix}
1794 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1795 By default no prefix is applied.
1797 @item segment_list_type @var{type}
1798 Select the listing format.
1800 The following values are recognized:
1803 Generate a flat list for the created segments, one segment per line.
1806 Generate a list for the created segments, one segment per line,
1807 each line matching the format (comma-separated values):
1809 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1812 @var{segment_filename} is the name of the output file generated by the
1813 muxer according to the provided pattern. CSV escaping (according to
1814 RFC4180) is applied if required.
1816 @var{segment_start_time} and @var{segment_end_time} specify
1817 the segment start and end time expressed in seconds.
1819 A list file with the suffix @code{".csv"} or @code{".ext"} will
1820 auto-select this format.
1822 @samp{ext} is deprecated in favor or @samp{csv}.
1825 Generate an ffconcat file for the created segments. The resulting file
1826 can be read using the FFmpeg @ref{concat} demuxer.
1828 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1829 auto-select this format.
1832 Generate an extended M3U8 file, version 3, compliant with
1833 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1835 A list file with the suffix @code{".m3u8"} will auto-select this format.
1838 If not specified the type is guessed from the list file name suffix.
1840 @item segment_time @var{time}
1841 Set segment duration to @var{time}, the value must be a duration
1842 specification. Default value is "2". See also the
1843 @option{segment_times} option.
1845 Note that splitting may not be accurate, unless you force the
1846 reference stream key-frames at the given time. See the introductory
1847 notice and the examples below.
1849 @item segment_atclocktime @var{1|0}
1850 If set to "1" split at regular clock time intervals starting from 00:00
1851 o'clock. The @var{time} value specified in @option{segment_time} is
1852 used for setting the length of the splitting interval.
1854 For example with @option{segment_time} set to "900" this makes it possible
1855 to create files at 12:00 o'clock, 12:15, 12:30, etc.
1857 Default value is "0".
1859 @item segment_clocktime_offset @var{duration}
1860 Delay the segment splitting times with the specified duration when using
1861 @option{segment_atclocktime}.
1863 For example with @option{segment_time} set to "900" and
1864 @option{segment_clocktime_offset} set to "300" this makes it possible to
1865 create files at 12:05, 12:20, 12:35, etc.
1867 Default value is "0".
1869 @item segment_clocktime_wrap_duration @var{duration}
1870 Force the segmenter to only start a new segment if a packet reaches the muxer
1871 within the specified duration after the segmenting clock time. This way you
1872 can make the segmenter more resilient to backward local time jumps, such as
1873 leap seconds or transition to standard time from daylight savings time.
1875 Default is the maximum possible duration which means starting a new segment
1876 regardless of the elapsed time since the last clock time.
1878 @item segment_time_delta @var{delta}
1879 Specify the accuracy time when selecting the start time for a
1880 segment, expressed as a duration specification. Default value is "0".
1882 When delta is specified a key-frame will start a new segment if its
1883 PTS satisfies the relation:
1885 PTS >= start_time - time_delta
1888 This option is useful when splitting video content, which is always
1889 split at GOP boundaries, in case a key frame is found just before the
1890 specified split time.
1892 In particular may be used in combination with the @file{ffmpeg} option
1893 @var{force_key_frames}. The key frame times specified by
1894 @var{force_key_frames} may not be set accurately because of rounding
1895 issues, with the consequence that a key frame time may result set just
1896 before the specified time. For constant frame rate videos a value of
1897 1/(2*@var{frame_rate}) should address the worst case mismatch between
1898 the specified time and the time set by @var{force_key_frames}.
1900 @item segment_times @var{times}
1901 Specify a list of split points. @var{times} contains a list of comma
1902 separated duration specifications, in increasing order. See also
1903 the @option{segment_time} option.
1905 @item segment_frames @var{frames}
1906 Specify a list of split video frame numbers. @var{frames} contains a
1907 list of comma separated integer numbers, in increasing order.
1909 This option specifies to start a new segment whenever a reference
1910 stream key frame is found and the sequential number (starting from 0)
1911 of the frame is greater or equal to the next value in the list.
1913 @item segment_wrap @var{limit}
1914 Wrap around segment index once it reaches @var{limit}.
1916 @item segment_start_number @var{number}
1917 Set the sequence number of the first segment. Defaults to @code{0}.
1919 @item strftime @var{1|0}
1920 Use the @code{strftime} function to define the name of the new
1921 segments to write. If this is selected, the output segment name must
1922 contain a @code{strftime} function template. Default value is
1925 @item break_non_keyframes @var{1|0}
1926 If enabled, allow segments to start on frames other than keyframes. This
1927 improves behavior on some players when the time between keyframes is
1928 inconsistent, but may make things worse on others, and can cause some oddities
1929 during seeking. Defaults to @code{0}.
1931 @item reset_timestamps @var{1|0}
1932 Reset timestamps at the beginning of each segment, so that each segment
1933 will start with near-zero timestamps. It is meant to ease the playback
1934 of the generated segments. May not work with some combinations of
1935 muxers/codecs. It is set to @code{0} by default.
1937 @item initial_offset @var{offset}
1938 Specify timestamp offset to apply to the output packet timestamps. The
1939 argument must be a time duration specification, and defaults to 0.
1941 @item write_empty_segments @var{1|0}
1942 If enabled, write an empty segment if there are no packets during the period a
1943 segment would usually span. Otherwise, the segment will be filled with the next
1944 packet written. Defaults to @code{0}.
1947 Make sure to require a closed GOP when encoding and to set the GOP
1948 size to fit your segment time constraint.
1950 @subsection Examples
1954 Remux the content of file @file{in.mkv} to a list of segments
1955 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
1956 generated segments to @file{out.list}:
1958 ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
1962 Segment input and set output format options for the output segments:
1964 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
1968 Segment the input file according to the split points specified by the
1969 @var{segment_times} option:
1971 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
1975 Use the @command{ffmpeg} @option{force_key_frames}
1976 option to force key frames in the input at the specified location, together
1977 with the segment option @option{segment_time_delta} to account for
1978 possible roundings operated when setting key frame times.
1980 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
1981 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
1983 In order to force key frames on the input file, transcoding is
1987 Segment the input file by splitting the input file according to the
1988 frame numbers sequence specified with the @option{segment_frames} option:
1990 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
1994 Convert the @file{in.mkv} to TS segments using the @code{libx264}
1995 and @code{aac} encoders:
1997 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
2001 Segment the input file, and create an M3U8 live playlist (can be used
2002 as live HLS source):
2004 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
2005 -segment_list_flags +live -segment_time 10 out%03d.mkv
2009 @section smoothstreaming
2011 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
2015 Specify the number of fragments kept in the manifest. Default 0 (keep all).
2017 @item extra_window_size
2018 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
2020 @item lookahead_count
2021 Specify the number of lookahead fragments. Default 2.
2023 @item min_frag_duration
2024 Specify the minimum fragment duration (in microseconds). Default 5000000.
2026 @item remove_at_exit
2027 Specify whether to remove all fragments when finished. Default 0 (do not remove).
2034 The fifo pseudo-muxer allows the separation of encoding and muxing by using
2035 first-in-first-out queue and running the actual muxer in a separate thread. This
2036 is especially useful in combination with the @ref{tee} muxer and can be used to
2037 send data to several destinations with different reliability/writing speed/latency.
2039 API users should be aware that callback functions (interrupt_callback,
2040 io_open and io_close) used within its AVFormatContext must be thread-safe.
2042 The behavior of the fifo muxer if the queue fills up or if the output fails is
2048 output can be transparently restarted with configurable delay between retries
2049 based on real time or time of the processed stream.
2052 encoding can be blocked during temporary failure, or continue transparently
2053 dropping packets in case fifo queue fills up.
2060 Specify the format name. Useful if it cannot be guessed from the
2064 Specify size of the queue (number of packets). Default value is 60.
2067 Specify format options for the underlying muxer. Muxer options can be specified
2068 as a list of @var{key}=@var{value} pairs separated by ':'.
2070 @item drop_pkts_on_overflow @var{bool}
2071 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
2072 rather than blocking the encoder. This makes it possible to continue streaming without
2073 delaying the input, at the cost of omitting part of the stream. By default
2074 this option is set to 0 (false), so in such cases the encoder will be blocked
2075 until the muxer processes some of the packets and none of them is lost.
2077 @item attempt_recovery @var{bool}
2078 If failure occurs, attempt to recover the output. This is especially useful
2079 when used with network output, since it makes it possible to restart streaming transparently.
2080 By default this option is set to 0 (false).
2082 @item max_recovery_attempts
2083 Sets maximum number of successive unsuccessful recovery attempts after which
2084 the output fails permanently. By default this option is set to 0 (unlimited).
2086 @item recovery_wait_time @var{duration}
2087 Waiting time before the next recovery attempt after previous unsuccessful
2088 recovery attempt. Default value is 5 seconds.
2090 @item recovery_wait_streamtime @var{bool}
2091 If set to 0 (false), the real time is used when waiting for the recovery
2092 attempt (i.e. the recovery will be attempted after at least
2093 recovery_wait_time seconds).
2094 If set to 1 (true), the time of the processed stream is taken into account
2095 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
2096 seconds of the stream is omitted).
2097 By default, this option is set to 0 (false).
2099 @item recover_any_error @var{bool}
2100 If set to 1 (true), recovery will be attempted regardless of type of the error
2101 causing the failure. By default this option is set to 0 (false) and in case of
2102 certain (usually permanent) errors the recovery is not attempted even when
2103 @var{attempt_recovery} is set to 1.
2105 @item restart_with_keyframe @var{bool}
2106 Specify whether to wait for the keyframe after recovering from
2107 queue overflow or failure. This option is set to 0 (false) by default.
2111 @subsection Examples
2116 Stream something to rtmp server, continue processing the stream at real-time
2117 rate even in case of temporary failure (network outage) and attempt to recover
2118 streaming every second indefinitely.
2120 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
2121 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
2129 The tee muxer can be used to write the same data to several outputs, such as files or streams.
2130 It can be used, for example, to stream a video over a network and save it to disk at the same time.
2132 It is different from specifying several outputs to the @command{ffmpeg}
2133 command-line tool. With the tee muxer, the audio and video data will be encoded only once.
2134 With conventional multiple outputs, multiple encoding operations in parallel are initiated,
2135 which can be a very expensive process. The tee muxer is not useful when using the libavformat API
2136 directly because it is then possible to feed the same packets to several muxers directly.
2138 Since the tee muxer does not represent any particular output format, ffmpeg cannot auto-select
2139 output streams. So all streams intended for output must be specified using @code{-map}. See
2142 Some encoders may need different options depending on the output format;
2143 the auto-detection of this can not work with the tee muxer, so they need to be explicitly specified.
2144 The main example is the @option{global_header} flag.
2146 The slave outputs are specified in the file name given to the muxer,
2147 separated by '|'. If any of the slave name contains the '|' separator,
2148 leading or trailing spaces or any special character, those must be
2149 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
2150 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
2156 @item use_fifo @var{bool}
2157 If set to 1, slave outputs will be processed in separate threads using the @ref{fifo}
2158 muxer. This allows to compensate for different speed/latency/reliability of
2159 outputs and setup transparent recovery. By default this feature is turned off.
2162 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
2166 Muxer options can be specified for each slave by prepending them as a list of
2167 @var{key}=@var{value} pairs separated by ':', between square brackets. If
2168 the options values contain a special character or the ':' separator, they
2169 must be escaped; note that this is a second level escaping.
2171 The following special options are also recognized:
2174 Specify the format name. Required if it cannot be guessed from the
2177 @item bsfs[/@var{spec}]
2178 Specify a list of bitstream filters to apply to the specified
2181 It is possible to specify to which streams a given bitstream filter
2182 applies, by appending a stream specifier to the option separated by
2183 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
2184 stream specifiers}).
2186 If the stream specifier is not specified, the bitstream filters will be
2187 applied to all streams in the output. This will cause that output operation
2188 to fail if the output contains streams to which the bitstream filter cannot
2189 be applied e.g. @code{h264_mp4toannexb} being applied to an output containing an audio stream.
2191 Options for a bitstream filter must be specified in the form of @code{opt=value}.
2193 Several bitstream filters can be specified, separated by ",".
2195 @item use_fifo @var{bool}
2196 This allows to override tee muxer use_fifo option for individual slave muxer.
2199 This allows to override tee muxer fifo_options for individual slave muxer.
2203 Select the streams that should be mapped to the slave output,
2204 specified by a stream specifier. If not specified, this defaults to
2205 all the mapped streams. This will cause that output operation to fail
2206 if the output format does not accept all mapped streams.
2208 You may use multiple stream specifiers separated by commas (@code{,}) e.g.: @code{a:0,v}
2211 Specify behaviour on output failure. This can be set to either @code{abort} (which is
2212 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
2213 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
2214 will continue without being affected.
2217 @subsection Examples
2221 Encode something and both archive it in a WebM file and stream it
2222 as MPEG-TS over UDP:
2224 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2225 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2229 As above, but continue streaming even if output to local file fails
2230 (for example local drive fills up):
2232 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2233 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2237 Use @command{ffmpeg} to encode the input, and send the output
2238 to three different destinations. The @code{dump_extra} bitstream
2239 filter is used to add extradata information to all the output video
2240 keyframes packets, as requested by the MPEG-TS format. The select
2241 option is applied to @file{out.aac} in order to make it contain only
2244 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2245 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
2249 As above, but select only stream @code{a:1} for the audio output. Note
2250 that a second level escaping must be performed, as ":" is a special
2251 character used to separate options.
2253 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2254 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
2258 @section webm_dash_manifest
2260 WebM DASH Manifest muxer.
2262 This muxer implements the WebM DASH Manifest specification to generate the DASH
2263 manifest XML. It also supports manifest generation for DASH live streams.
2265 For more information see:
2269 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
2271 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
2276 This muxer supports the following options:
2279 @item adaptation_sets
2280 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
2281 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
2282 audio and video streams. Any number of adaptation sets can be added using this option.
2285 Set this to 1 to create a live stream DASH Manifest. Default: 0.
2287 @item chunk_start_index
2288 Start index of the first chunk. This will go in the @samp{startNumber} attribute
2289 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
2291 @item chunk_duration_ms
2292 Duration of each chunk in milliseconds. This will go in the @samp{duration}
2293 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
2295 @item utc_timing_url
2296 URL of the page that will return the UTC timestamp in ISO format. This will go
2297 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
2300 @item time_shift_buffer_depth
2301 Smallest time (in seconds) shifting buffer for which any Representation is
2302 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
2303 attribute of the @samp{MPD} element. Default: 60.
2305 @item minimum_update_period
2306 Minimum update period (in seconds) of the manifest. This will go in the
2307 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
2313 ffmpeg -f webm_dash_manifest -i video1.webm \
2314 -f webm_dash_manifest -i video2.webm \
2315 -f webm_dash_manifest -i audio1.webm \
2316 -f webm_dash_manifest -i audio2.webm \
2317 -map 0 -map 1 -map 2 -map 3 \
2319 -f webm_dash_manifest \
2320 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
2326 WebM Live Chunk Muxer.
2328 This muxer writes out WebM headers and chunks as separate files which can be
2329 consumed by clients that support WebM Live streams via DASH.
2333 This muxer supports the following options:
2336 @item chunk_start_index
2337 Index of the first chunk (defaults to 0).
2340 Filename of the header where the initialization data will be written.
2342 @item audio_chunk_duration
2343 Duration of each audio chunk in milliseconds (defaults to 5000).
2348 ffmpeg -f v4l2 -i /dev/video0 \
2352 -s 640x360 -keyint_min 30 -g 30 \
2354 -header webm_live_video_360.hdr \
2355 -chunk_start_index 1 \
2356 webm_live_video_360_%d.chk \
2361 -header webm_live_audio_128.hdr \
2362 -chunk_start_index 1 \
2363 -audio_chunk_duration 1000 \
2364 webm_live_audio_128_%d.chk