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. Range is from -1 to 32767, where -1 disables
109 silence detection. Silence detection can only be used with version 3 of the
111 Silence detection must be disabled for use with the AcoustID service. Default is -1.
114 Version of algorithm to fingerprint with. Range is 0 to 4.
115 Version 3 enables silence detection. Default is 1.
118 Format to output the fingerprint as. Accepts the following options:
121 Binary raw fingerprint
124 Binary compressed fingerprint
127 Base64 compressed fingerprint @emph{(default)}
136 CRC (Cyclic Redundancy Check) testing format.
138 This muxer computes and prints the Adler-32 CRC of all the input audio
139 and video frames. By default audio frames are converted to signed
140 16-bit raw audio and video frames to raw video before computing the
143 The output of the muxer consists of a single line of the form:
144 CRC=0x@var{CRC}, where @var{CRC} is a hexadecimal number 0-padded to
145 8 digits containing the CRC for all the decoded input frames.
147 See also the @ref{framecrc} muxer.
151 For example to compute the CRC of the input, and store it in the file
154 ffmpeg -i INPUT -f crc out.crc
157 You can print the CRC to stdout with the command:
159 ffmpeg -i INPUT -f crc -
162 You can select the output format of each frame with @command{ffmpeg} by
163 specifying the audio and video codec and format. For example to
164 compute the CRC of the input audio converted to PCM unsigned 8-bit
165 and the input video converted to MPEG-2 video, use the command:
167 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f crc -
172 Adobe Flash Video Format muxer.
174 This muxer accepts the following options:
178 @item flvflags @var{flags}
183 @item aac_seq_header_detect
184 Place AAC sequence header based on audio stream data.
186 @item no_sequence_end
187 Disable sequence end tag.
190 Disable metadata tag.
192 @item no_duration_filesize
193 Disable duration and filesize in metadata when they are equal to zero
194 at the end of stream. (Be used to non-seekable living stream).
196 @item add_keyframe_index
197 Used to facilitate seeking; particularly for HTTP pseudo streaming.
204 Dynamic Adaptive Streaming over HTTP (DASH) muxer that creates segments
205 and manifest files according to the MPEG-DASH standard ISO/IEC 23009-1:2014.
207 For more information see:
211 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
213 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
216 It creates a MPD manifest file and segment files for each stream.
218 The segment filename might contain pre-defined identifiers used with SegmentTemplate
219 as defined in section 5.3.9.4.4 of the standard. Available identifiers are "$RepresentationID$",
220 "$Number$", "$Bandwidth$" and "$Time$".
221 In addition to the standard identifiers, an ffmpeg-specific "$ext$" identifier is also supported.
222 When specified ffmpeg will replace $ext$ in the file name with muxing format's extensions such as mp4, webm etc.,
225 ffmpeg -re -i <input> -map 0 -map 0 -c:a libfdk_aac -c:v libx264 \
226 -b:v:0 800k -b:v:1 300k -s:v:1 320x170 -profile:v:1 baseline \
227 -profile:v:0 main -bf 1 -keyint_min 120 -g 120 -sc_threshold 0 \
228 -b_strategy 0 -ar:a:1 22050 -use_timeline 1 -use_template 1 \
229 -window_size 5 -adaptation_sets "id=0,streams=v id=1,streams=a" \
230 -f dash /path/to/out.mpd
234 @item min_seg_duration @var{microseconds}
235 This is a deprecated option to set the segment length in microseconds, use @var{seg_duration} instead.
236 @item seg_duration @var{duration}
237 Set the segment length in seconds (fractional value can be set). The value is
238 treated as average segment duration when @var{use_template} is enabled and
239 @var{use_timeline} is disabled and as minimum segment duration for all the other
241 @item window_size @var{size}
242 Set the maximum number of segments kept in the manifest.
243 @item extra_window_size @var{size}
244 Set the maximum number of segments kept outside of the manifest before removing from disk.
245 @item remove_at_exit @var{remove}
246 Enable (1) or disable (0) removal of all segments when finished.
247 @item use_template @var{template}
248 Enable (1) or disable (0) use of SegmentTemplate instead of SegmentList.
249 @item use_timeline @var{timeline}
250 Enable (1) or disable (0) use of SegmentTimeline in SegmentTemplate.
251 @item single_file @var{single_file}
252 Enable (1) or disable (0) storing all segments in one file, accessed using byte ranges.
253 @item single_file_name @var{file_name}
254 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.
255 @item init_seg_name @var{init_name}
256 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.
257 @item media_seg_name @var{segment_name}
258 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.
259 @item utc_timing_url @var{utc_url}
260 URL of the page that will return the UTC timestamp in ISO format. Example: "https://time.akamai.com/?iso"
261 @item method @var{method}
262 Use the given HTTP method to create output files. Generally set to PUT or POST.
263 @item http_user_agent @var{user_agent}
264 Override User-Agent field in HTTP header. Applicable only for HTTP output.
265 @item http_persistent @var{http_persistent}
266 Use persistent HTTP connections. Applicable only for HTTP output.
267 @item hls_playlist @var{hls_playlist}
268 Generate HLS playlist files as well. The master playlist is generated with the filename master.m3u8.
269 One media playlist file is generated for each stream with filenames media_0.m3u8, media_1.m3u8, etc.
270 @item streaming @var{streaming}
271 Enable (1) or disable (0) chunk streaming mode of output. In chunk streaming
272 mode, each frame will be a moof fragment which forms a chunk.
273 @item adaptation_sets @var{adaptation_sets}
274 Assign streams to AdaptationSets. Syntax is "id=x,streams=a,b,c id=y,streams=d,e" with x and y being the IDs
275 of the adaptation sets and a,b,c,d and e are the indices of the mapped streams.
277 To map all video (or audio) streams to an AdaptationSet, "v" (or "a") can be used as stream identifier instead of IDs.
279 When no assignment is defined, this defaults to an AdaptationSet for each stream.
281 Optional syntax is "id=x,descriptor=descriptor_string,streams=a,b,c id=y,streams=d,e" and so on, descriptor is useful to the scheme defined by ISO/IEC 23009-1:2014/Amd.2:2015.
282 For example, -adaptation_sets "id=0,descriptor=<SupplementalProperty schemeIdUri=\"urn:mpeg:dash:srd:2014\" value=\"0,0,0,1,1,2,2\"/>,streams=v".
283 Please note that descriptor string should be a self-closing xml tag.
284 @item timeout @var{timeout}
285 Set timeout for socket I/O operations. Applicable only for HTTP output.
286 @item index_correction @var{index_correction}
287 Enable (1) or Disable (0) segment index correction logic. Applicable only when
288 @var{use_template} is enabled and @var{use_timeline} is disabled.
290 When enabled, the logic monitors the flow of segment indexes. If a streams's
291 segment index value is not at the expected real time position, then the logic
292 corrects that index value.
294 Typically this logic is needed in live streaming use cases. The network bandwidth
295 fluctuations are common during long run streaming. Each fluctuation can cause
296 the segment indexes fall behind the expected real time position.
297 @item format_options @var{options_list}
298 Set container format (mp4/webm) options using a @code{:} separated list of
299 key=value parameters. Values containing @code{:} special characters must be
302 @item global_sidx @var{global_sidx}
303 Write global SIDX atom. Applicable only for single file, mp4 output, non-streaming mode.
305 @item dash_segment_type @var{dash_segment_type}
309 If this flag is set, the dash segment files format will be selected based on the stream codec. This is the default mode.
312 If this flag is set, the dash segment files will be in in ISOBMFF format.
315 If this flag is set, the dash segment files will be in in WebM format.
318 @item ignore_io_errors @var{ignore_io_errors}
319 Ignore IO errors during open and write. Useful for long-duration runs with network output.
321 @item lhls @var{lhls}
322 Enable Low-latency HLS(LHLS). Adds #EXT-X-PREFETCH tag with current segment's URI.
323 Apple doesn't have an official spec for LHLS. Meanwhile hls.js player folks are
324 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
325 This option will also try to comply with the above open spec, till Apple's spec officially supports it.
326 Applicable only when @var{streaming} and @var{hls_playlist} options are enabled.
327 This is an experimental feature.
329 @item master_m3u8_publish_rate @var{master_m3u8_publish_rate}
330 Publish master playlist repeatedly every after specified number of segment intervals.
337 Per-packet CRC (Cyclic Redundancy Check) testing format.
339 This muxer computes and prints the Adler-32 CRC for each audio
340 and video packet. By default audio frames are converted to signed
341 16-bit raw audio and video frames to raw video before computing the
344 The output of the muxer consists of a line for each audio and video
347 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
350 @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
355 For example to compute the CRC of the audio and video frames in
356 @file{INPUT}, converted to raw audio and video packets, and store it
357 in the file @file{out.crc}:
359 ffmpeg -i INPUT -f framecrc out.crc
362 To print the information to stdout, use the command:
364 ffmpeg -i INPUT -f framecrc -
367 With @command{ffmpeg}, you can select the output format to which the
368 audio and video frames are encoded before computing the CRC for each
369 packet by specifying the audio and video codec. For example, to
370 compute the CRC of each decoded input audio frame converted to PCM
371 unsigned 8-bit and of each decoded input video frame converted to
372 MPEG-2 video, use the command:
374 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
377 See also the @ref{crc} muxer.
382 Per-packet hash testing format.
384 This muxer computes and prints a cryptographic hash for each audio
385 and video packet. This can be used for packet-by-packet equality
386 checks without having to individually do a binary comparison on each.
388 By default audio frames are converted to signed 16-bit raw audio and
389 video frames to raw video before computing the hash, but the output
390 of explicit conversions to other codecs can also be used. It uses the
391 SHA-256 cryptographic hash function by default, but supports several
394 The output of the muxer consists of a line for each audio and video
397 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
400 @var{hash} is a hexadecimal number representing the computed hash
404 @item hash @var{algorithm}
405 Use the cryptographic hash function specified by the string @var{algorithm}.
406 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
407 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
408 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
409 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
415 To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
416 converted to raw audio and video packets, and store it in the file
419 ffmpeg -i INPUT -f framehash out.sha256
422 To print the information to stdout, using the MD5 hash function, use
425 ffmpeg -i INPUT -f framehash -hash md5 -
428 See also the @ref{hash} muxer.
433 Per-packet MD5 testing format.
435 This is a variant of the @ref{framehash} muxer. Unlike that muxer,
436 it defaults to using the MD5 hash function.
440 To compute the MD5 hash of the audio and video frames in @file{INPUT},
441 converted to raw audio and video packets, and store it in the file
444 ffmpeg -i INPUT -f framemd5 out.md5
447 To print the information to stdout, use the command:
449 ffmpeg -i INPUT -f framemd5 -
452 See also the @ref{framehash} and @ref{md5} muxers.
459 It accepts the following options:
463 Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
464 for looping indefinitely (default).
467 Force the delay (expressed in centiseconds) after the last frame. Each frame
468 ends with a delay until the next frame. The default is @code{-1}, which is a
469 special value to tell the muxer to re-use the previous delay. In case of a
470 loop, you might want to customize this value to mark a pause for instance.
473 For example, to encode a gif looping 10 times, with a 5 seconds delay between
476 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
479 Note 1: if you wish to extract the frames into separate GIF files, you need to
480 force the @ref{image2} muxer:
482 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
485 Note 2: the GIF format has a very large time base: the delay between two frames
486 can therefore not be smaller than one centi second.
493 This muxer computes and prints a cryptographic hash of all the input
494 audio and video frames. This can be used for equality checks without
495 having to do a complete binary comparison.
497 By default audio frames are converted to signed 16-bit raw audio and
498 video frames to raw video before computing the hash, but the output
499 of explicit conversions to other codecs can also be used. Timestamps
500 are ignored. It uses the SHA-256 cryptographic hash function by default,
501 but supports several other algorithms.
503 The output of the muxer consists of a single line of the form:
504 @var{algo}=@var{hash}, where @var{algo} is a short string representing
505 the hash function used, and @var{hash} is a hexadecimal number
506 representing the computed hash.
509 @item hash @var{algorithm}
510 Use the cryptographic hash function specified by the string @var{algorithm}.
511 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
512 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
513 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
514 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
520 To compute the SHA-256 hash of the input converted to raw audio and
521 video, and store it in the file @file{out.sha256}:
523 ffmpeg -i INPUT -f hash out.sha256
526 To print an MD5 hash to stdout use the command:
528 ffmpeg -i INPUT -f hash -hash md5 -
531 See also the @ref{framehash} muxer.
536 Apple HTTP Live Streaming muxer that segments MPEG-TS according to
537 the HTTP Live Streaming (HLS) specification.
539 It creates a playlist file, and one or more segment files. The output filename
540 specifies the playlist filename.
542 By default, the muxer creates a file for each segment produced. These files
543 have the same name as the playlist, followed by a sequential number and a
546 Make sure to require a closed GOP when encoding and to set the GOP
547 size to fit your segment time constraint.
549 For example, to convert an input file with @command{ffmpeg}:
551 ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
553 This example will produce the playlist, @file{out.m3u8}, and segment files:
554 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
556 See also the @ref{segment} muxer, which provides a more generic and
557 flexible implementation of a segmenter, and can be used to perform HLS
562 This muxer supports the following options:
565 @item hls_init_time @var{seconds}
566 Set the initial target segment length in seconds. Default value is @var{0}.
567 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
568 After the initial playlist is filled @command{ffmpeg} will cut segments
569 at duration equal to @code{hls_time}
571 @item hls_time @var{seconds}
572 Set the target segment length in seconds. Default value is 2.
573 Segment will be cut on the next key frame after this time has passed.
575 @item hls_list_size @var{size}
576 Set the maximum number of playlist entries. If set to 0 the list file
577 will contain all the segments. Default value is 5.
579 @item hls_delete_threshold @var{size}
580 Set the number of unreferenced segments to keep on disk before @code{hls_flags delete_segments}
581 deletes them. Increase this to allow continue clients to download segments which
582 were recently referenced in the playlist. Default value is 1, meaning segments older than
583 @code{hls_list_size+1} will be deleted.
585 @item hls_ts_options @var{options_list}
586 Set output format options using a :-separated list of key=value
587 parameters. Values containing @code{:} special characters must be
590 @item hls_wrap @var{wrap}
591 This is a deprecated option, you can use @code{hls_list_size}
592 and @code{hls_flags delete_segments} instead it
594 This option is useful to avoid to fill the disk with many segment
595 files, and limits the maximum number of segment files written to disk
599 @item hls_start_number_source
600 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
601 Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
602 segment and subtitle filenames. In any case, if @code{hls_flags append_list}
603 is set and read playlist sequence number is greater than the specified start sequence number,
604 then that value will be used as start value.
606 It accepts the following values:
610 @item generic (default)
611 Set the starting sequence numbers according to @var{start_number} option value.
614 The start number will be the seconds since epoch (1970-01-01 00:00:00)
617 The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
621 @item start_number @var{number}
622 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
623 when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
624 Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
627 @item hls_allow_cache @var{allowcache}
628 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
630 @item hls_base_url @var{baseurl}
631 Append @var{baseurl} to every entry in the playlist.
632 Useful to generate playlists with absolute paths.
634 Note that the playlist sequence number must be unique for each segment
635 and it is not to be confused with the segment filename sequence number
636 which can be cyclic, for example if the @option{wrap} option is
639 @item hls_segment_filename @var{filename}
640 Set the segment filename. Unless @code{hls_flags single_file} is set,
641 @var{filename} is used as a string format with the segment number:
643 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
645 This example will produce the playlist, @file{out.m3u8}, and segment files:
646 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
648 @var{filename} may contain full path or relative path specification,
649 but only the file name part without any path info will be contained in the m3u8 segment list.
650 Should a relative path be specified, the path of the created segment
651 files will be relative to the current working directory.
652 When strftime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
654 When @code{var_stream_map} is set with two or more variant streams, the
655 @var{filename} pattern must contain the string "%v", this string specifies
656 the position of variant stream index in the generated segment file names.
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 'file_%v_%03d.ts' out_%v.m3u8
662 This example will produce the playlists segment file sets:
663 @file{file_0_000.ts}, @file{file_0_001.ts}, @file{file_0_002.ts}, etc. and
664 @file{file_1_000.ts}, @file{file_1_001.ts}, @file{file_1_002.ts}, etc.
666 The string "%v" may be present in the filename or in the last directory name
667 containing the file, but only in one of them. (Additionally, %v may appear multiple times in the last
668 sub-directory or filename.) If the string %v is present in the directory name, then
669 sub-directories are created after expanding the directory name pattern. This
670 enables creation of segments corresponding to different variant streams in
673 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
674 -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" \
675 -hls_segment_filename 'vs%v/file_%03d.ts' vs%v/out.m3u8
677 This example will produce the playlists segment file sets:
678 @file{vs0/file_000.ts}, @file{vs0/file_001.ts}, @file{vs0/file_002.ts}, etc. and
679 @file{vs1/file_000.ts}, @file{vs1/file_001.ts}, @file{vs1/file_002.ts}, etc.
682 Same as strftime option, will be deprecated.
685 Use strftime() on @var{filename} to expand the segment filename with localtime.
686 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
687 hls_flag and %%d will be the specifier.
689 ffmpeg -i in.nut -strftime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
691 This example will produce the playlist, @file{out.m3u8}, and segment files:
692 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
693 Note: On some systems/environments, the @code{%s} specifier is not available. See
694 @code{strftime()} documentation.
696 ffmpeg -i in.nut -strftime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
698 This example will produce the playlist, @file{out.m3u8}, and segment files:
699 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
701 @item use_localtime_mkdir
702 Same as strftime_mkdir option, will be deprecated .
705 Used together with -strftime_mkdir, it will create all subdirectories which
706 is expanded in @var{filename}.
708 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y%m%d/file-%Y%m%d-%s.ts' out.m3u8
710 This example will create a directory 201560215 (if it does not exist), and then
711 produce the playlist, @file{out.m3u8}, and segment files:
712 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
715 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y/%m/%d/file-%Y%m%d-%s.ts' out.m3u8
717 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
718 produce the playlist, @file{out.m3u8}, and segment files:
719 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
722 @item hls_key_info_file @var{key_info_file}
723 Use the information in @var{key_info_file} for segment encryption. The first
724 line of @var{key_info_file} specifies the key URI written to the playlist. The
725 key URL is used to access the encryption key during playback. The second line
726 specifies the path to the key file used to obtain the key during the encryption
727 process. The key file is read as a single packed array of 16 octets in binary
728 format. The optional third line specifies the initialization vector (IV) as a
729 hexadecimal string to be used instead of the segment sequence number (default)
730 for encryption. Changes to @var{key_info_file} will result in segment
731 encryption with the new key/IV and an entry in the playlist for the new key
732 URI/IV if @code{hls_flags periodic_rekey} is enabled.
734 Key info file format:
743 http://server/file.key
748 Example key file paths:
756 0123456789ABCDEF0123456789ABCDEF
759 Key info file example:
761 http://server/file.key
763 0123456789ABCDEF0123456789ABCDEF
766 Example shell script:
770 openssl rand 16 > file.key
771 echo $BASE_URL/file.key > file.keyinfo
772 echo file.key >> file.keyinfo
773 echo $(openssl rand -hex 16) >> file.keyinfo
774 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
775 -hls_key_info_file file.keyinfo out.m3u8
778 @item -hls_enc @var{enc}
779 Enable (1) or disable (0) the AES128 encryption.
780 When enabled every segment generated is encrypted and the encryption key
781 is saved as @var{playlist name}.key.
783 @item -hls_enc_key @var{key}
784 Hex-coded 16byte key to encrypt the segments, by default it
785 is randomly generated.
787 @item -hls_enc_key_url @var{keyurl}
788 If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
791 @item -hls_enc_iv @var{iv}
792 Hex-coded 16byte initialization vector for every segment instead
793 of the autogenerated ones.
795 @item hls_segment_type @var{flags}
800 Output segment files in MPEG-2 Transport Stream format. This is
801 compatible with all HLS versions.
804 Output segment files in fragmented MP4 format, similar to MPEG-DASH.
805 fmp4 files may be used in HLS version 7 and above.
809 @item hls_fmp4_init_filename @var{filename}
810 Set filename to the fragment files header file, default filename is @file{init.mp4}.
812 When @code{var_stream_map} is set with two or more variant streams, the
813 @var{filename} pattern must contain the string "%v", this string specifies
814 the position of variant stream index in the generated init file names.
815 The string "%v" may be present in the filename or in the last directory name
816 containing the file. If the string is present in the directory name, then
817 sub-directories are created after expanding the directory name pattern. This
818 enables creation of init files corresponding to different variant streams in
821 @item hls_flags @var{flags}
826 If this flag is set, the muxer will store all segments in a single MPEG-TS
827 file, and will use byte ranges in the playlist. HLS playlists generated with
828 this way will have the version number 4.
831 ffmpeg -i in.nut -hls_flags single_file out.m3u8
833 Will produce the playlist, @file{out.m3u8}, and a single segment file,
836 @item delete_segments
837 Segment files removed from the playlist are deleted after a period of time
838 equal to the duration of the segment plus the duration of the playlist.
841 Append new segments into the end of old segment list,
842 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
844 @item round_durations
845 Round the duration info in the playlist file segment info to integer
846 values, instead of using floating point.
849 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
850 first segment's information.
853 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
856 The file specified by @code{hls_key_info_file} will be checked periodically and
857 detect updates to the encryption info. Be sure to replace this file atomically,
858 including the file containing the AES encryption key.
860 @item independent_segments
861 Add the @code{#EXT-X-INDEPENDENT-SEGMENTS} to playlists that has video segments
862 and when all the segments of that playlist are guaranteed to start with a Key frame.
865 Add the @code{#EXT-X-I-FRAMES-ONLY} to playlists that has video segments
866 and can play only I-frames in the @code{#EXT-X-BYTERANGE} mode.
869 Allow segments to start on frames other than keyframes. This improves
870 behavior on some players when the time between keyframes is inconsistent,
871 but may make things worse on others, and can cause some oddities during
872 seeking. This flag should be used with the @code{hls_time} option.
874 @item program_date_time
875 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
877 @item second_level_segment_index
878 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
879 besides date/time values when strftime is on.
880 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
882 @item second_level_segment_size
883 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
884 expression besides date/time values when strftime is on.
885 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
887 @item second_level_segment_duration
888 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
889 expression besides date/time values when strftime is on.
890 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
893 ffmpeg -i sample.mpeg \
894 -f hls -hls_time 3 -hls_list_size 5 \
895 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
896 -strftime 1 -strftime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
898 This will produce segments like this:
899 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
902 Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
903 serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
904 before they have been added to the m3u8 playlist. This flag also affects how m3u8 playlist files are created.
905 If this flag is set, all playlist files will written into temporary file and renamed after they are complete, similarly as segments are handled.
906 But playlists with @code{file} protocol and with type (@code{hls_playlist_type}) other than @code{vod}
907 are always written into temporary file regardless of this flag. Master playlist files (@code{master_pl_name}), if any, with @code{file} protocol,
908 are always written into temporary file regardless of this flag if @code{master_pl_publish_rate} value is other than zero.
912 @item hls_playlist_type event
913 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
914 @option{hls_list_size} to 0; the playlist can only be appended to.
916 @item hls_playlist_type vod
917 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
918 @option{hls_list_size} to 0; the playlist must not change.
921 Use the given HTTP method to create the hls files.
923 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
925 This example will upload all the mpegts segment files to the HTTP
926 server using the HTTP PUT method, and update the m3u8 files every
927 @code{refresh} times using the same method.
928 Note that the HTTP server must support the given method for uploading
931 @item http_user_agent
932 Override User-Agent field in HTTP header. Applicable only for HTTP output.
935 Map string which specifies how to group the audio, video and subtitle streams
936 into different variant streams. The variant stream groups are separated
938 Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
939 the keys to specify audio, video and subtitle streams respectively.
940 Allowed values are 0 to 9 (limited just based on practical usage).
942 When there are two or more variant streams, the output filename pattern must
943 contain the string "%v", this string specifies the position of variant stream
944 index in the output media playlist filenames. The string "%v" may be present in
945 the filename or in the last directory name containing the file. If the string is
946 present in the directory name, then sub-directories are created after expanding
947 the directory name pattern. This enables creation of variant streams in
951 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
952 -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" \
953 http://example.com/live/out_%v.m3u8
955 This example creates two hls variant streams. The first variant stream will
956 contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
957 second variant stream will contain video stream of bitrate 256k and audio
958 stream of bitrate 32k. Here, two media playlist with file names out_0.m3u8 and
959 out_1.m3u8 will be created. If you want something meaningful text instead of indexes
960 in result names, you may specify names for each or some of the variants
961 as in the following example.
965 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
966 -map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0,name:my_hd v:1,a:1,name:my_sd" \
967 http://example.com/live/out_%v.m3u8
970 This example creates two hls variant streams as in the previous one.
971 But here, the two media playlist with file names out_my_hd.m3u8 and
972 out_my_sd.m3u8 will be created.
975 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
976 -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
977 http://example.com/live/out_%v.m3u8
979 This example creates three hls variant streams. The first variant stream will
980 be a video only stream with video bitrate 1000k, the second variant stream will
981 be an audio only stream with bitrate 64k and the third variant stream will be a
982 video only stream with bitrate 256k. Here, three media playlist with file names
983 out_0.m3u8, out_1.m3u8 and out_2.m3u8 will be created.
985 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
986 -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" \
987 http://example.com/live/vs_%v/out.m3u8
989 This example creates the variant streams in subdirectories. Here, the first
990 media playlist is created at @file{http://example.com/live/vs_0/out.m3u8} and
991 the second one at @file{http://example.com/live/vs_1/out.m3u8}.
993 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k \
994 -map 0:a -map 0:a -map 0:v -map 0:v -f hls \
995 -var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
996 -master_pl_name master.m3u8 \
997 http://example.com/live/out_%v.m3u8
999 This example creates two audio only and two video only variant streams. In
1000 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1001 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1002 and they are mapped to the two video only variant streams with audio group names
1003 'aud_low' and 'aud_high'.
1005 By default, a single hls variant containing all the encoded streams is created.
1008 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
1009 -map 0:a -map 0:a -map 0:v -f hls \
1010 -var_stream_map "a:0,agroup:aud_low,default:yes a:1,agroup:aud_low v:0,agroup:aud_low" \
1011 -master_pl_name master.m3u8 \
1012 http://example.com/live/out_%v.m3u8
1014 This example creates two audio only and one video only variant streams. In
1015 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1016 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1017 and they are mapped to the one video only variant streams with audio group name
1018 'aud_low', and the audio group have default stat is NO or YES.
1020 By default, a single hls variant containing all the encoded streams is created.
1023 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
1024 -map 0:a -map 0:a -map 0:v -f hls \
1025 -var_stream_map "a:0,agroup:aud_low,default:yes,language:ENG a:1,agroup:aud_low,language:CHN v:0,agroup:aud_low" \
1026 -master_pl_name master.m3u8 \
1027 http://example.com/live/out_%v.m3u8
1029 This example creates two audio only and one video only variant streams. In
1030 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1031 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1032 and they are mapped to the one video only variant streams with audio group name
1033 'aud_low', and the audio group have default stat is NO or YES, and one audio
1034 have and language is named ENG, the other audio language is named CHN.
1036 By default, a single hls variant containing all the encoded streams is created.
1039 Map string which specifies different closed captions groups and their
1040 attributes. The closed captions stream groups are separated by space.
1041 Expected string format is like this
1042 "ccgroup:<group name>,instreamid:<INSTREAM-ID>,language:<language code> ....".
1043 'ccgroup' and 'instreamid' are mandatory attributes. 'language' is an optional
1045 The closed captions groups configured using this option are mapped to different
1046 variant streams by providing the same 'ccgroup' name in the
1047 @code{var_stream_map} string. If @code{var_stream_map} is not set, then the
1048 first available ccgroup in @code{cc_stream_map} is mapped to the output variant
1049 stream. The examples for these two use cases are given below.
1052 ffmpeg -re -i in.ts -b:v 1000k -b:a 64k -a53cc 1 -f hls \
1053 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en" \
1054 -master_pl_name master.m3u8 \
1055 http://example.com/live/out.m3u8
1057 This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=CLOSED-CAPTIONS} in
1058 the master playlist with group name 'cc', language 'en' (english) and
1059 INSTREAM-ID 'CC1'. Also, it adds @code{CLOSED-CAPTIONS} attribute with group
1060 name 'cc' for the output variant stream.
1062 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1063 -a53cc:0 1 -a53cc:1 1\
1064 -map 0:v -map 0:a -map 0:v -map 0:a -f hls \
1065 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en ccgroup:cc,instreamid:CC2,language:sp" \
1066 -var_stream_map "v:0,a:0,ccgroup:cc v:1,a:1,ccgroup:cc" \
1067 -master_pl_name master.m3u8 \
1068 http://example.com/live/out_%v.m3u8
1070 This example adds two @code{#EXT-X-MEDIA} tags with @code{TYPE=CLOSED-CAPTIONS} in
1071 the master playlist for the INSTREAM-IDs 'CC1' and 'CC2'. Also, it adds
1072 @code{CLOSED-CAPTIONS} attribute with group name 'cc' for the two output variant
1075 @item master_pl_name
1076 Create HLS master playlist with the given name.
1079 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
1081 This example creates HLS master playlist with name master.m3u8 and it is
1082 published at http://example.com/live/
1084 @item master_pl_publish_rate
1085 Publish master play list repeatedly every after specified number of segment intervals.
1088 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
1089 -hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
1092 This example creates HLS master playlist with name master.m3u8 and keep
1093 publishing it repeatedly every after 30 segments i.e. every after 60s.
1095 @item http_persistent
1096 Use persistent HTTP connections. Applicable only for HTTP output.
1099 Set timeout for socket I/O operations. Applicable only for HTTP output.
1101 @item -ignore_io_errors
1102 Ignore IO errors during open, write and delete. Useful for long-duration runs with network output.
1105 Set custom HTTP headers, can override built in default headers. Applicable only for HTTP output.
1114 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
1118 Size cannot exceed 256 pixels in any dimension
1121 Only BMP and PNG images can be stored
1124 If a BMP image is used, it must be one of the following pixel formats:
1126 BMP Bit Depth FFmpeg Pixel Format
1136 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
1139 If a PNG image is used, it must use the rgba pixel format
1147 The image file muxer writes video frames to image files.
1149 The output filenames are specified by a pattern, which can be used to
1150 produce sequentially numbered series of files.
1151 The pattern may contain the string "%d" or "%0@var{N}d", this string
1152 specifies the position of the characters representing a numbering in
1153 the filenames. If the form "%0@var{N}d" is used, the string
1154 representing the number in each filename is 0-padded to @var{N}
1155 digits. The literal character '%' can be specified in the pattern with
1158 If the pattern contains "%d" or "%0@var{N}d", the first filename of
1159 the file list specified will contain the number 1, all the following
1160 numbers will be sequential.
1162 The pattern may contain a suffix which is used to automatically
1163 determine the format of the image files to write.
1165 For example the pattern "img-%03d.bmp" will specify a sequence of
1166 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
1167 @file{img-010.bmp}, etc.
1168 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
1169 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
1172 @subsection Examples
1174 The following example shows how to use @command{ffmpeg} for creating a
1175 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
1176 taking one image every second from the input video:
1178 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
1181 Note that with @command{ffmpeg}, if the format is not specified with the
1182 @code{-f} option and the output filename specifies an image file
1183 format, the image2 muxer is automatically selected, so the previous
1184 command can be written as:
1186 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
1189 Note also that the pattern must not necessarily contain "%d" or
1190 "%0@var{N}d", for example to create a single image file
1191 @file{img.jpeg} from the start of the input video you can employ the command:
1193 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
1196 The @option{strftime} option allows you to expand the filename with
1197 date and time information. Check the documentation of
1198 the @code{strftime()} function for the syntax.
1200 For example to generate image files from the @code{strftime()}
1201 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
1204 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
1207 You can set the file name with current frame's PTS:
1209 ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
1216 If set to 1, expand the filename with pts from pkt->pts.
1220 Start the sequence from the specified number. Default value is 1.
1223 If set to 1, the filename will always be interpreted as just a
1224 filename, not a pattern, and the corresponding file will be continuously
1225 overwritten with new images. Default value is 0.
1228 If set to 1, expand the filename with date and time information from
1229 @code{strftime()}. Default value is 0.
1232 The image muxer supports the .Y.U.V image file format. This format is
1233 special in that that each image frame consists of three files, for
1234 each of the YUV420P components. To read or write this image file format,
1235 specify the name of the '.Y' file. The muxer will automatically open the
1236 '.U' and '.V' files as required.
1240 Matroska container muxer.
1242 This muxer implements the matroska and webm container specs.
1244 @subsection Metadata
1246 The recognized metadata settings in this muxer are:
1250 Set title name provided to a single track.
1253 Specify the language of the track in the Matroska languages form.
1255 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
1256 639-2/B) form (like "fre" for French), or a language code mixed with a
1257 country code for specialities in languages (like "fre-ca" for Canadian
1261 Set stereo 3D video layout of two views in a single video track.
1263 The following values are recognized:
1268 Both views are arranged side by side, Left-eye view is on the left
1270 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
1272 Both views are arranged in top-bottom orientation, Left-eye view is on top
1273 @item checkerboard_rl
1274 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
1275 @item checkerboard_lr
1276 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
1277 @item row_interleaved_rl
1278 Each view is constituted by a row based interleaving, Right-eye view is first row
1279 @item row_interleaved_lr
1280 Each view is constituted by a row based interleaving, Left-eye view is first row
1281 @item col_interleaved_rl
1282 Both views are arranged in a column based interleaving manner, Right-eye view is first column
1283 @item col_interleaved_lr
1284 Both views are arranged in a column based interleaving manner, Left-eye view is first column
1285 @item anaglyph_cyan_red
1286 All frames are in anaglyph format viewable through red-cyan filters
1288 Both views are arranged side by side, Right-eye view is on the left
1289 @item anaglyph_green_magenta
1290 All frames are in anaglyph format viewable through green-magenta filters
1292 Both eyes laced in one Block, Left-eye view is first
1294 Both eyes laced in one Block, Right-eye view is first
1298 For example a 3D WebM clip can be created using the following command line:
1300 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
1305 This muxer supports the following options:
1308 @item reserve_index_space
1309 By default, this muxer writes the index for seeking (called cues in Matroska
1310 terms) at the end of the file, because it cannot know in advance how much space
1311 to leave for the index at the beginning of the file. However for some use cases
1312 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
1313 index at the beginning of the file.
1315 If this option is set to a non-zero value, the muxer will reserve a given amount
1316 of space in the file header and then try to write the cues there when the muxing
1317 finishes. If the available space does not suffice, muxing will fail. A safe size
1318 for most use cases should be about 50kB per hour of video.
1320 Note that cues are only written if the output is seekable and this option will
1321 have no effect if it is not.
1329 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
1330 defaults to using the MD5 hash function.
1332 @subsection Examples
1334 To compute the MD5 hash of the input converted to raw
1335 audio and video, and store it in the file @file{out.md5}:
1337 ffmpeg -i INPUT -f md5 out.md5
1340 You can print the MD5 to stdout with the command:
1342 ffmpeg -i INPUT -f md5 -
1345 See also the @ref{hash} and @ref{framemd5} muxers.
1347 @section mov, mp4, ismv
1349 MOV/MP4/ISMV (Smooth Streaming) muxer.
1351 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
1352 file has all the metadata about all packets stored in one location
1353 (written at the end of the file, it can be moved to the start for
1354 better playback by adding @var{faststart} to the @var{movflags}, or
1355 using the @command{qt-faststart} tool). A fragmented
1356 file consists of a number of fragments, where packets and metadata
1357 about these packets are stored together. Writing a fragmented
1358 file has the advantage that the file is decodable even if the
1359 writing is interrupted (while a normal MOV/MP4 is undecodable if
1360 it is not properly finished), and it requires less memory when writing
1361 very long files (since writing normal MOV/MP4 files stores info about
1362 every single packet in memory until the file is closed). The downside
1363 is that it is less compatible with other applications.
1367 Fragmentation is enabled by setting one of the AVOptions that define
1368 how to cut the file into fragments:
1371 @item -moov_size @var{bytes}
1372 Reserves space for the moov atom at the beginning of the file instead of placing the
1373 moov atom at the end. If the space reserved is insufficient, muxing will fail.
1374 @item -movflags frag_keyframe
1375 Start a new fragment at each video keyframe.
1376 @item -frag_duration @var{duration}
1377 Create fragments that are @var{duration} microseconds long.
1378 @item -frag_size @var{size}
1379 Create fragments that contain up to @var{size} bytes of payload data.
1380 @item -movflags frag_custom
1381 Allow the caller to manually choose when to cut fragments, by
1382 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
1383 the packets written so far. (This is only useful with other
1384 applications integrating libavformat, not from @command{ffmpeg}.)
1385 @item -min_frag_duration @var{duration}
1386 Don't create fragments that are shorter than @var{duration} microseconds long.
1389 If more than one condition is specified, fragments are cut when
1390 one of the specified conditions is fulfilled. The exception to this is
1391 @code{-min_frag_duration}, which has to be fulfilled for any of the other
1392 conditions to apply.
1394 Additionally, the way the output file is written can be adjusted
1395 through a few other options:
1398 @item -movflags empty_moov
1399 Write an initial moov atom directly at the start of the file, without
1400 describing any samples in it. Generally, an mdat/moov pair is written
1401 at the start of the file, as a normal MOV/MP4 file, containing only
1402 a short portion of the file. With this option set, there is no initial
1403 mdat atom, and the moov atom only describes the tracks but has
1406 This option is implicitly set when writing ismv (Smooth Streaming) files.
1407 @item -movflags separate_moof
1408 Write a separate moof (movie fragment) atom for each track. Normally,
1409 packets for all tracks are written in a moof atom (which is slightly
1410 more efficient), but with this option set, the muxer writes one moof/mdat
1411 pair for each track, making it easier to separate tracks.
1413 This option is implicitly set when writing ismv (Smooth Streaming) files.
1414 @item -movflags skip_sidx
1415 Skip writing of sidx atom. When bitrate overhead due to sidx atom is high,
1416 this option could be used for cases where sidx atom is not mandatory.
1417 When global_sidx flag is enabled, this option will be ignored.
1418 @item -movflags faststart
1419 Run a second pass moving the index (moov atom) to the beginning of the file.
1420 This operation can take a while, and will not work in various situations such
1421 as fragmented output, thus it is not enabled by default.
1422 @item -movflags rtphint
1423 Add RTP hinting tracks to the output file.
1424 @item -movflags disable_chpl
1425 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
1426 and a QuickTime chapter track are written to the file. With this option
1427 set, only the QuickTime chapter track will be written. Nero chapters can
1428 cause failures when the file is reprocessed with certain tagging programs, like
1429 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
1430 @item -movflags omit_tfhd_offset
1431 Do not write any absolute base_data_offset in tfhd atoms. This avoids
1432 tying fragments to absolute byte positions in the file/streams.
1433 @item -movflags default_base_moof
1434 Similarly to the omit_tfhd_offset, this flag avoids writing the
1435 absolute base_data_offset field in tfhd atoms, but does so by using
1436 the new default-base-is-moof flag instead. This flag is new from
1437 14496-12:2012. This may make the fragments easier to parse in certain
1438 circumstances (avoiding basing track fragment location calculations
1439 on the implicit end of the previous track fragment).
1441 Specify @code{on} to force writing a timecode track, @code{off} to disable it
1442 and @code{auto} to write a timecode track only for mov and mp4 output (default).
1443 @item -movflags negative_cts_offsets
1444 Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
1445 be negative. This enables the initial sample to have DTS/CTS of zero, and
1446 reduces the need for edit lists for some cases such as video tracks with
1447 B-frames. Additionally, eases conformance with the DASH-IF interoperability
1450 This option is implicitly set when writing ismv (Smooth Streaming) files.
1452 Write producer time reference box (PRFT) with a specified time source for the
1453 NTP field in the PRFT box. Set value as @samp{wallclock} to specify timesource
1454 as wallclock time and @samp{pts} to specify timesource as input packets' PTS
1457 Setting value to @samp{pts} is applicable only for a live encoding use case,
1458 where PTS values are set as as wallclock time at the source. For example, an
1459 encoding use case with decklink capture source where @option{video_pts} and
1460 @option{audio_pts} are set to @samp{abs_wallclock}.
1465 Smooth Streaming content can be pushed in real time to a publishing
1466 point on IIS with this muxer. Example:
1468 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
1471 @subsection Audible AAX
1473 Audible AAX files are encrypted M4B files, and they can be decrypted by specifying a 4 byte activation secret.
1475 ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
1480 The MP3 muxer writes a raw MP3 stream with the following optional features:
1483 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
1484 2.4 are supported, the @code{id3v2_version} private option controls which one is
1485 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
1488 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
1489 The pictures are supplied to the muxer in form of a video stream with a single
1490 packet. There can be any number of those streams, each will correspond to a
1491 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
1492 to APIC @var{description} and @var{picture type} respectively. See
1493 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
1495 Note that the APIC frames must be written at the beginning, so the muxer will
1496 buffer the audio frames until it gets all the pictures. It is therefore advised
1497 to provide the pictures as soon as possible to avoid excessive buffering.
1500 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
1501 default, but will be written only if the output is seekable. The
1502 @code{write_xing} private option can be used to disable it. The frame contains
1503 various information that may be useful to the decoder, like the audio duration
1507 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1508 enabled with the @code{write_id3v1} private option, but as its capabilities are
1509 very limited, its usage is not recommended.
1514 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1516 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1519 To attach a picture to an mp3 file select both the audio and the picture stream
1522 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1523 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1526 Write a "clean" MP3 without any extra features:
1528 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1533 MPEG transport stream muxer.
1535 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1537 The recognized metadata settings in mpegts muxer are @code{service_provider}
1538 and @code{service_name}. If they are not set the default for
1539 @code{service_provider} is @samp{FFmpeg} and the default for
1540 @code{service_name} is @samp{Service01}.
1544 The muxer options are:
1547 @item mpegts_transport_stream_id @var{integer}
1548 Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
1549 Default is @code{0x0001}.
1551 @item mpegts_original_network_id @var{integer}
1552 Set the @samp{original_network_id}. This is unique identifier of a
1553 network in DVB. Its main use is in the unique identification of a service
1554 through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
1557 @item mpegts_service_id @var{integer}
1558 Set the @samp{service_id}, also known as program in DVB. Default is
1561 @item mpegts_service_type @var{integer}
1562 Set the program @samp{service_type}. Default is @code{digital_tv}.
1563 Accepts the following options:
1566 Any hexadecimal value between @code{0x01} and @code{0xff} as defined in
1571 Digital Radio service.
1574 @item advanced_codec_digital_radio
1575 Advanced Codec Digital Radio service.
1576 @item mpeg2_digital_hdtv
1577 MPEG2 Digital HDTV service.
1578 @item advanced_codec_digital_sdtv
1579 Advanced Codec Digital SDTV service.
1580 @item advanced_codec_digital_hdtv
1581 Advanced Codec Digital HDTV service.
1584 @item mpegts_pmt_start_pid @var{integer}
1585 Set the first PID for PMT. Default is @code{0x1000}. Max is @code{0x1f00}.
1587 @item mpegts_start_pid @var{integer}
1588 Set the first PID for data packets. Default is @code{0x0100}. Max is
1591 @item mpegts_m2ts_mode @var{boolean}
1592 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
1595 @item muxrate @var{integer}
1596 Set a constant muxrate. Default is VBR.
1598 @item pes_payload_size @var{integer}
1599 Set minimum PES packet payload in bytes. Default is @code{2930}.
1601 @item mpegts_flags @var{flags}
1602 Set mpegts flags. Accepts the following options:
1604 @item resend_headers
1605 Reemit PAT/PMT before writing the next packet.
1607 Use LATM packetization for AAC.
1608 @item pat_pmt_at_frames
1609 Reemit PAT and PMT at each video frame.
1611 Conform to System B (DVB) instead of System A (ATSC).
1612 @item initial_discontinuity
1613 Mark the initial packet of each stream as discontinuity.
1616 @item mpegts_copyts @var{boolean}
1617 Preserve original timestamps, if value is set to @code{1}. Default value
1618 is @code{-1}, which results in shifting timestamps so that they start from 0.
1620 @item omit_video_pes_length @var{boolean}
1621 Omit the PES packet length for video packets. Default is @code{1} (true).
1623 @item pcr_period @var{integer}
1624 Override the default PCR retransmission time in milliseconds. Default is
1625 @code{-1} which means that the PCR interval will be determined automatically:
1626 20 ms is used for CBR streams, the highest multiple of the frame duration which
1627 is less than 100 ms is used for VBR streams.
1629 @item pat_period @var{duration}
1630 Maximum time in seconds between PAT/PMT tables. Default is @code{0.1}.
1632 @item sdt_period @var{duration}
1633 Maximum time in seconds between SDT tables. Default is @code{0.5}.
1635 @item tables_version @var{integer}
1636 Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
1637 This option allows updating stream structure so that standard consumer may
1638 detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
1639 usage) or restart @command{ffmpeg} instance, cyclically changing
1640 @option{tables_version} value:
1643 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1644 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1646 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1647 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1648 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1656 ffmpeg -i file.mpg -c copy \
1657 -mpegts_original_network_id 0x1122 \
1658 -mpegts_transport_stream_id 0x3344 \
1659 -mpegts_service_id 0x5566 \
1660 -mpegts_pmt_start_pid 0x1500 \
1661 -mpegts_start_pid 0x150 \
1662 -metadata service_provider="Some provider" \
1663 -metadata service_name="Some Channel" \
1667 @section mxf, mxf_d10, mxf_opatom
1673 The muxer options are:
1676 @item store_user_comments @var{bool}
1677 Set if user comments should be stored if available or never.
1678 IRT D-10 does not allow user comments. The default is thus to write them for
1679 mxf and mxf_opatom but not for mxf_d10
1686 This muxer does not generate any output file, it is mainly useful for
1687 testing or benchmarking purposes.
1689 For example to benchmark decoding with @command{ffmpeg} you can use the
1692 ffmpeg -benchmark -i INPUT -f null out.null
1695 Note that the above command does not read or write the @file{out.null}
1696 file, but specifying the output file is required by the @command{ffmpeg}
1699 Alternatively you can write the command as:
1701 ffmpeg -benchmark -i INPUT -f null -
1707 @item -syncpoints @var{flags}
1708 Change the syncpoint usage in nut:
1710 @item @var{default} use the normal low-overhead seeking aids.
1711 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1712 Use of this option is not recommended, as the resulting files are very damage
1713 sensitive and seeking is not possible. Also in general the overhead from
1714 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1715 all growing data tables, allowing to mux endless streams with limited memory
1716 and without these disadvantages.
1717 @item @var{timestamped} extend the syncpoint with a wallclock field.
1719 The @var{none} and @var{timestamped} flags are experimental.
1720 @item -write_index @var{bool}
1721 Write index at the end, the default is to write an index.
1725 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1730 Ogg container muxer.
1733 @item -page_duration @var{duration}
1734 Preferred page duration, in microseconds. The muxer will attempt to create
1735 pages that are approximately @var{duration} microseconds long. This allows the
1736 user to compromise between seek granularity and container overhead. The default
1737 is 1 second. A value of 0 will fill all segments, making pages as large as
1738 possible. A value of 1 will effectively use 1 packet-per-page in most
1739 situations, giving a small seek granularity at the cost of additional container
1741 @item -serial_offset @var{value}
1742 Serial value from which to set the streams serial number.
1743 Setting it to different and sufficiently large values ensures that the produced
1744 ogg files can be safely chained.
1749 @section segment, stream_segment, ssegment
1751 Basic stream segmenter.
1753 This muxer outputs streams to a number of separate files of nearly
1754 fixed duration. Output filename pattern can be set in a fashion
1755 similar to @ref{image2}, or by using a @code{strftime} template if
1756 the @option{strftime} option is enabled.
1758 @code{stream_segment} is a variant of the muxer used to write to
1759 streaming output formats, i.e. which do not require global headers,
1760 and is recommended for outputting e.g. to MPEG transport stream segments.
1761 @code{ssegment} is a shorter alias for @code{stream_segment}.
1763 Every segment starts with a keyframe of the selected reference stream,
1764 which is set through the @option{reference_stream} option.
1766 Note that if you want accurate splitting for a video file, you need to
1767 make the input key frames correspond to the exact splitting times
1768 expected by the segmenter, or the segment muxer will start the new
1769 segment with the key frame found next after the specified start
1772 The segment muxer works best with a single constant frame rate video.
1774 Optionally it can generate a list of the created segments, by setting
1775 the option @var{segment_list}. The list type is specified by the
1776 @var{segment_list_type} option. The entry filenames in the segment
1777 list are set by default to the basename of the corresponding segment
1780 See also the @ref{hls} muxer, which provides a more specific
1781 implementation for HLS segmentation.
1785 The segment muxer supports the following options:
1788 @item increment_tc @var{1|0}
1789 if set to @code{1}, increment timecode between each segment
1790 If this is selected, the input need to have
1791 a timecode in the first video stream. Default value is
1794 @item reference_stream @var{specifier}
1795 Set the reference stream, as specified by the string @var{specifier}.
1796 If @var{specifier} is set to @code{auto}, the reference is chosen
1797 automatically. Otherwise it must be a stream specifier (see the ``Stream
1798 specifiers'' chapter in the ffmpeg manual) which specifies the
1799 reference stream. The default value is @code{auto}.
1801 @item segment_format @var{format}
1802 Override the inner container format, by default it is guessed by the filename
1805 @item segment_format_options @var{options_list}
1806 Set output format options using a :-separated list of key=value
1807 parameters. Values containing the @code{:} special character must be
1810 @item segment_list @var{name}
1811 Generate also a listfile named @var{name}. If not specified no
1812 listfile is generated.
1814 @item segment_list_flags @var{flags}
1815 Set flags affecting the segment list generation.
1817 It currently supports the following flags:
1820 Allow caching (only affects M3U8 list files).
1823 Allow live-friendly file generation.
1826 @item segment_list_size @var{size}
1827 Update the list file so that it contains at most @var{size}
1828 segments. If 0 the list file will contain all the segments. Default
1831 @item segment_list_entry_prefix @var{prefix}
1832 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1833 By default no prefix is applied.
1835 @item segment_list_type @var{type}
1836 Select the listing format.
1838 The following values are recognized:
1841 Generate a flat list for the created segments, one segment per line.
1844 Generate a list for the created segments, one segment per line,
1845 each line matching the format (comma-separated values):
1847 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1850 @var{segment_filename} is the name of the output file generated by the
1851 muxer according to the provided pattern. CSV escaping (according to
1852 RFC4180) is applied if required.
1854 @var{segment_start_time} and @var{segment_end_time} specify
1855 the segment start and end time expressed in seconds.
1857 A list file with the suffix @code{".csv"} or @code{".ext"} will
1858 auto-select this format.
1860 @samp{ext} is deprecated in favor or @samp{csv}.
1863 Generate an ffconcat file for the created segments. The resulting file
1864 can be read using the FFmpeg @ref{concat} demuxer.
1866 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1867 auto-select this format.
1870 Generate an extended M3U8 file, version 3, compliant with
1871 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1873 A list file with the suffix @code{".m3u8"} will auto-select this format.
1876 If not specified the type is guessed from the list file name suffix.
1878 @item segment_time @var{time}
1879 Set segment duration to @var{time}, the value must be a duration
1880 specification. Default value is "2". See also the
1881 @option{segment_times} option.
1883 Note that splitting may not be accurate, unless you force the
1884 reference stream key-frames at the given time. See the introductory
1885 notice and the examples below.
1887 @item segment_atclocktime @var{1|0}
1888 If set to "1" split at regular clock time intervals starting from 00:00
1889 o'clock. The @var{time} value specified in @option{segment_time} is
1890 used for setting the length of the splitting interval.
1892 For example with @option{segment_time} set to "900" this makes it possible
1893 to create files at 12:00 o'clock, 12:15, 12:30, etc.
1895 Default value is "0".
1897 @item segment_clocktime_offset @var{duration}
1898 Delay the segment splitting times with the specified duration when using
1899 @option{segment_atclocktime}.
1901 For example with @option{segment_time} set to "900" and
1902 @option{segment_clocktime_offset} set to "300" this makes it possible to
1903 create files at 12:05, 12:20, 12:35, etc.
1905 Default value is "0".
1907 @item segment_clocktime_wrap_duration @var{duration}
1908 Force the segmenter to only start a new segment if a packet reaches the muxer
1909 within the specified duration after the segmenting clock time. This way you
1910 can make the segmenter more resilient to backward local time jumps, such as
1911 leap seconds or transition to standard time from daylight savings time.
1913 Default is the maximum possible duration which means starting a new segment
1914 regardless of the elapsed time since the last clock time.
1916 @item segment_time_delta @var{delta}
1917 Specify the accuracy time when selecting the start time for a
1918 segment, expressed as a duration specification. Default value is "0".
1920 When delta is specified a key-frame will start a new segment if its
1921 PTS satisfies the relation:
1923 PTS >= start_time - time_delta
1926 This option is useful when splitting video content, which is always
1927 split at GOP boundaries, in case a key frame is found just before the
1928 specified split time.
1930 In particular may be used in combination with the @file{ffmpeg} option
1931 @var{force_key_frames}. The key frame times specified by
1932 @var{force_key_frames} may not be set accurately because of rounding
1933 issues, with the consequence that a key frame time may result set just
1934 before the specified time. For constant frame rate videos a value of
1935 1/(2*@var{frame_rate}) should address the worst case mismatch between
1936 the specified time and the time set by @var{force_key_frames}.
1938 @item segment_times @var{times}
1939 Specify a list of split points. @var{times} contains a list of comma
1940 separated duration specifications, in increasing order. See also
1941 the @option{segment_time} option.
1943 @item segment_frames @var{frames}
1944 Specify a list of split video frame numbers. @var{frames} contains a
1945 list of comma separated integer numbers, in increasing order.
1947 This option specifies to start a new segment whenever a reference
1948 stream key frame is found and the sequential number (starting from 0)
1949 of the frame is greater or equal to the next value in the list.
1951 @item segment_wrap @var{limit}
1952 Wrap around segment index once it reaches @var{limit}.
1954 @item segment_start_number @var{number}
1955 Set the sequence number of the first segment. Defaults to @code{0}.
1957 @item strftime @var{1|0}
1958 Use the @code{strftime} function to define the name of the new
1959 segments to write. If this is selected, the output segment name must
1960 contain a @code{strftime} function template. Default value is
1963 @item break_non_keyframes @var{1|0}
1964 If enabled, allow segments to start on frames other than keyframes. This
1965 improves behavior on some players when the time between keyframes is
1966 inconsistent, but may make things worse on others, and can cause some oddities
1967 during seeking. Defaults to @code{0}.
1969 @item reset_timestamps @var{1|0}
1970 Reset timestamps at the beginning of each segment, so that each segment
1971 will start with near-zero timestamps. It is meant to ease the playback
1972 of the generated segments. May not work with some combinations of
1973 muxers/codecs. It is set to @code{0} by default.
1975 @item initial_offset @var{offset}
1976 Specify timestamp offset to apply to the output packet timestamps. The
1977 argument must be a time duration specification, and defaults to 0.
1979 @item write_empty_segments @var{1|0}
1980 If enabled, write an empty segment if there are no packets during the period a
1981 segment would usually span. Otherwise, the segment will be filled with the next
1982 packet written. Defaults to @code{0}.
1985 Make sure to require a closed GOP when encoding and to set the GOP
1986 size to fit your segment time constraint.
1988 @subsection Examples
1992 Remux the content of file @file{in.mkv} to a list of segments
1993 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
1994 generated segments to @file{out.list}:
1996 ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
2000 Segment input and set output format options for the output segments:
2002 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
2006 Segment the input file according to the split points specified by the
2007 @var{segment_times} option:
2009 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
2013 Use the @command{ffmpeg} @option{force_key_frames}
2014 option to force key frames in the input at the specified location, together
2015 with the segment option @option{segment_time_delta} to account for
2016 possible roundings operated when setting key frame times.
2018 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
2019 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
2021 In order to force key frames on the input file, transcoding is
2025 Segment the input file by splitting the input file according to the
2026 frame numbers sequence specified with the @option{segment_frames} option:
2028 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
2032 Convert the @file{in.mkv} to TS segments using the @code{libx264}
2033 and @code{aac} encoders:
2035 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
2039 Segment the input file, and create an M3U8 live playlist (can be used
2040 as live HLS source):
2042 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
2043 -segment_list_flags +live -segment_time 10 out%03d.mkv
2047 @section smoothstreaming
2049 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
2053 Specify the number of fragments kept in the manifest. Default 0 (keep all).
2055 @item extra_window_size
2056 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
2058 @item lookahead_count
2059 Specify the number of lookahead fragments. Default 2.
2061 @item min_frag_duration
2062 Specify the minimum fragment duration (in microseconds). Default 5000000.
2064 @item remove_at_exit
2065 Specify whether to remove all fragments when finished. Default 0 (do not remove).
2072 Per stream hash testing format.
2074 This muxer computes and prints a cryptographic hash of all the input frames,
2075 on a per-stream basis. This can be used for equality checks without having
2076 to do a complete binary comparison.
2078 By default audio frames are converted to signed 16-bit raw audio and
2079 video frames to raw video before computing the hash, but the output
2080 of explicit conversions to other codecs can also be used. Timestamps
2081 are ignored. It uses the SHA-256 cryptographic hash function by default,
2082 but supports several other algorithms.
2084 The output of the muxer consists of one line per stream of the form:
2085 @var{streamindex},@var{streamtype},@var{algo}=@var{hash}, where
2086 @var{streamindex} is the index of the mapped stream, @var{streamtype} is a
2087 single characer indicating the type of stream, @var{algo} is a short string
2088 representing the hash function used, and @var{hash} is a hexadecimal number
2089 representing the computed hash.
2092 @item hash @var{algorithm}
2093 Use the cryptographic hash function specified by the string @var{algorithm}.
2094 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
2095 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
2096 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
2097 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
2101 @subsection Examples
2103 To compute the SHA-256 hash of the input converted to raw audio and
2104 video, and store it in the file @file{out.sha256}:
2106 ffmpeg -i INPUT -f streamhash out.sha256
2109 To print an MD5 hash to stdout use the command:
2111 ffmpeg -i INPUT -f streamhash -hash md5 -
2114 See also the @ref{hash} and @ref{framehash} muxers.
2119 The fifo pseudo-muxer allows the separation of encoding and muxing by using
2120 first-in-first-out queue and running the actual muxer in a separate thread. This
2121 is especially useful in combination with the @ref{tee} muxer and can be used to
2122 send data to several destinations with different reliability/writing speed/latency.
2124 API users should be aware that callback functions (interrupt_callback,
2125 io_open and io_close) used within its AVFormatContext must be thread-safe.
2127 The behavior of the fifo muxer if the queue fills up or if the output fails is
2133 output can be transparently restarted with configurable delay between retries
2134 based on real time or time of the processed stream.
2137 encoding can be blocked during temporary failure, or continue transparently
2138 dropping packets in case fifo queue fills up.
2145 Specify the format name. Useful if it cannot be guessed from the
2149 Specify size of the queue (number of packets). Default value is 60.
2152 Specify format options for the underlying muxer. Muxer options can be specified
2153 as a list of @var{key}=@var{value} pairs separated by ':'.
2155 @item drop_pkts_on_overflow @var{bool}
2156 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
2157 rather than blocking the encoder. This makes it possible to continue streaming without
2158 delaying the input, at the cost of omitting part of the stream. By default
2159 this option is set to 0 (false), so in such cases the encoder will be blocked
2160 until the muxer processes some of the packets and none of them is lost.
2162 @item attempt_recovery @var{bool}
2163 If failure occurs, attempt to recover the output. This is especially useful
2164 when used with network output, since it makes it possible to restart streaming transparently.
2165 By default this option is set to 0 (false).
2167 @item max_recovery_attempts
2168 Sets maximum number of successive unsuccessful recovery attempts after which
2169 the output fails permanently. By default this option is set to 0 (unlimited).
2171 @item recovery_wait_time @var{duration}
2172 Waiting time before the next recovery attempt after previous unsuccessful
2173 recovery attempt. Default value is 5 seconds.
2175 @item recovery_wait_streamtime @var{bool}
2176 If set to 0 (false), the real time is used when waiting for the recovery
2177 attempt (i.e. the recovery will be attempted after at least
2178 recovery_wait_time seconds).
2179 If set to 1 (true), the time of the processed stream is taken into account
2180 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
2181 seconds of the stream is omitted).
2182 By default, this option is set to 0 (false).
2184 @item recover_any_error @var{bool}
2185 If set to 1 (true), recovery will be attempted regardless of type of the error
2186 causing the failure. By default this option is set to 0 (false) and in case of
2187 certain (usually permanent) errors the recovery is not attempted even when
2188 @var{attempt_recovery} is set to 1.
2190 @item restart_with_keyframe @var{bool}
2191 Specify whether to wait for the keyframe after recovering from
2192 queue overflow or failure. This option is set to 0 (false) by default.
2196 @subsection Examples
2201 Stream something to rtmp server, continue processing the stream at real-time
2202 rate even in case of temporary failure (network outage) and attempt to recover
2203 streaming every second indefinitely.
2205 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
2206 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
2214 The tee muxer can be used to write the same data to several outputs, such as files or streams.
2215 It can be used, for example, to stream a video over a network and save it to disk at the same time.
2217 It is different from specifying several outputs to the @command{ffmpeg}
2218 command-line tool. With the tee muxer, the audio and video data will be encoded only once.
2219 With conventional multiple outputs, multiple encoding operations in parallel are initiated,
2220 which can be a very expensive process. The tee muxer is not useful when using the libavformat API
2221 directly because it is then possible to feed the same packets to several muxers directly.
2223 Since the tee muxer does not represent any particular output format, ffmpeg cannot auto-select
2224 output streams. So all streams intended for output must be specified using @code{-map}. See
2227 Some encoders may need different options depending on the output format;
2228 the auto-detection of this can not work with the tee muxer, so they need to be explicitly specified.
2229 The main example is the @option{global_header} flag.
2231 The slave outputs are specified in the file name given to the muxer,
2232 separated by '|'. If any of the slave name contains the '|' separator,
2233 leading or trailing spaces or any special character, those must be
2234 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
2235 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
2241 @item use_fifo @var{bool}
2242 If set to 1, slave outputs will be processed in separate threads using the @ref{fifo}
2243 muxer. This allows to compensate for different speed/latency/reliability of
2244 outputs and setup transparent recovery. By default this feature is turned off.
2247 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
2251 Muxer options can be specified for each slave by prepending them as a list of
2252 @var{key}=@var{value} pairs separated by ':', between square brackets. If
2253 the options values contain a special character or the ':' separator, they
2254 must be escaped; note that this is a second level escaping.
2256 The following special options are also recognized:
2259 Specify the format name. Required if it cannot be guessed from the
2262 @item bsfs[/@var{spec}]
2263 Specify a list of bitstream filters to apply to the specified
2266 It is possible to specify to which streams a given bitstream filter
2267 applies, by appending a stream specifier to the option separated by
2268 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
2269 stream specifiers}).
2271 If the stream specifier is not specified, the bitstream filters will be
2272 applied to all streams in the output. This will cause that output operation
2273 to fail if the output contains streams to which the bitstream filter cannot
2274 be applied e.g. @code{h264_mp4toannexb} being applied to an output containing an audio stream.
2276 Options for a bitstream filter must be specified in the form of @code{opt=value}.
2278 Several bitstream filters can be specified, separated by ",".
2280 @item use_fifo @var{bool}
2281 This allows to override tee muxer use_fifo option for individual slave muxer.
2284 This allows to override tee muxer fifo_options for individual slave muxer.
2288 Select the streams that should be mapped to the slave output,
2289 specified by a stream specifier. If not specified, this defaults to
2290 all the mapped streams. This will cause that output operation to fail
2291 if the output format does not accept all mapped streams.
2293 You may use multiple stream specifiers separated by commas (@code{,}) e.g.: @code{a:0,v}
2296 Specify behaviour on output failure. This can be set to either @code{abort} (which is
2297 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
2298 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
2299 will continue without being affected.
2302 @subsection Examples
2306 Encode something and both archive it in a WebM file and stream it
2307 as MPEG-TS over UDP:
2309 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2310 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2314 As above, but continue streaming even if output to local file fails
2315 (for example local drive fills up):
2317 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2318 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2322 Use @command{ffmpeg} to encode the input, and send the output
2323 to three different destinations. The @code{dump_extra} bitstream
2324 filter is used to add extradata information to all the output video
2325 keyframes packets, as requested by the MPEG-TS format. The select
2326 option is applied to @file{out.aac} in order to make it contain only
2329 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2330 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
2334 As above, but select only stream @code{a:1} for the audio output. Note
2335 that a second level escaping must be performed, as ":" is a special
2336 character used to separate options.
2338 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2339 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
2343 @section webm_dash_manifest
2345 WebM DASH Manifest muxer.
2347 This muxer implements the WebM DASH Manifest specification to generate the DASH
2348 manifest XML. It also supports manifest generation for DASH live streams.
2350 For more information see:
2354 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
2356 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
2361 This muxer supports the following options:
2364 @item adaptation_sets
2365 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
2366 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
2367 audio and video streams. Any number of adaptation sets can be added using this option.
2370 Set this to 1 to create a live stream DASH Manifest. Default: 0.
2372 @item chunk_start_index
2373 Start index of the first chunk. This will go in the @samp{startNumber} attribute
2374 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
2376 @item chunk_duration_ms
2377 Duration of each chunk in milliseconds. This will go in the @samp{duration}
2378 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
2380 @item utc_timing_url
2381 URL of the page that will return the UTC timestamp in ISO format. This will go
2382 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
2385 @item time_shift_buffer_depth
2386 Smallest time (in seconds) shifting buffer for which any Representation is
2387 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
2388 attribute of the @samp{MPD} element. Default: 60.
2390 @item minimum_update_period
2391 Minimum update period (in seconds) of the manifest. This will go in the
2392 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
2398 ffmpeg -f webm_dash_manifest -i video1.webm \
2399 -f webm_dash_manifest -i video2.webm \
2400 -f webm_dash_manifest -i audio1.webm \
2401 -f webm_dash_manifest -i audio2.webm \
2402 -map 0 -map 1 -map 2 -map 3 \
2404 -f webm_dash_manifest \
2405 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
2411 WebM Live Chunk Muxer.
2413 This muxer writes out WebM headers and chunks as separate files which can be
2414 consumed by clients that support WebM Live streams via DASH.
2418 This muxer supports the following options:
2421 @item chunk_start_index
2422 Index of the first chunk (defaults to 0).
2425 Filename of the header where the initialization data will be written.
2427 @item audio_chunk_duration
2428 Duration of each audio chunk in milliseconds (defaults to 5000).
2433 ffmpeg -f v4l2 -i /dev/video0 \
2437 -s 640x360 -keyint_min 30 -g 30 \
2439 -header webm_live_video_360.hdr \
2440 -chunk_start_index 1 \
2441 webm_live_video_360_%d.chk \
2446 -header webm_live_audio_128.hdr \
2447 -chunk_start_index 1 \
2448 -audio_chunk_duration 1000 \
2449 webm_live_audio_128_%d.chk