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 @item frag_duration @var{duration}
240 Set the length in seconds of fragments within segments (fractional value can be set).
241 @item frag_type @var{type}
242 Set the type of interval for fragmentation.
243 @item window_size @var{size}
244 Set the maximum number of segments kept in the manifest.
245 @item extra_window_size @var{size}
246 Set the maximum number of segments kept outside of the manifest before removing from disk.
247 @item remove_at_exit @var{remove}
248 Enable (1) or disable (0) removal of all segments when finished.
249 @item use_template @var{template}
250 Enable (1) or disable (0) use of SegmentTemplate instead of SegmentList.
251 @item use_timeline @var{timeline}
252 Enable (1) or disable (0) use of SegmentTimeline in SegmentTemplate.
253 @item single_file @var{single_file}
254 Enable (1) or disable (0) storing all segments in one file, accessed using byte ranges.
255 @item single_file_name @var{file_name}
256 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.
257 @item init_seg_name @var{init_name}
258 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.
259 @item media_seg_name @var{segment_name}
260 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.
261 @item utc_timing_url @var{utc_url}
262 URL of the page that will return the UTC timestamp in ISO format. Example: "https://time.akamai.com/?iso"
263 @item method @var{method}
264 Use the given HTTP method to create output files. Generally set to PUT or POST.
265 @item http_user_agent @var{user_agent}
266 Override User-Agent field in HTTP header. Applicable only for HTTP output.
267 @item http_persistent @var{http_persistent}
268 Use persistent HTTP connections. Applicable only for HTTP output.
269 @item hls_playlist @var{hls_playlist}
270 Generate HLS playlist files as well. The master playlist is generated with the filename master.m3u8.
271 One media playlist file is generated for each stream with filenames media_0.m3u8, media_1.m3u8, etc.
272 @item streaming @var{streaming}
273 Enable (1) or disable (0) chunk streaming mode of output. In chunk streaming
274 mode, each frame will be a moof fragment which forms a chunk.
275 @item adaptation_sets @var{adaptation_sets}
276 Assign streams to AdaptationSets. Syntax is "id=x,streams=a,b,c id=y,streams=d,e" with x and y being the IDs
277 of the adaptation sets and a,b,c,d and e are the indices of the mapped streams.
279 To map all video (or audio) streams to an AdaptationSet, "v" (or "a") can be used as stream identifier instead of IDs.
281 When no assignment is defined, this defaults to an AdaptationSet for each stream.
283 Optional syntax is "id=x,seg_duration=x,frag_duration=x,frag_type=type,descriptor=descriptor_string,streams=a,b,c id=y,seg_duration=y,frag_type=type,streams=d,e" and so on,
284 descriptor is useful to the scheme defined by ISO/IEC 23009-1:2014/Amd.2:2015.
285 For example, -adaptation_sets "id=0,descriptor=<SupplementalProperty schemeIdUri=\"urn:mpeg:dash:srd:2014\" value=\"0,0,0,1,1,2,2\"/>,streams=v".
286 Please note that descriptor string should be a self-closing xml tag.
287 seg_duration, frag_duration and frag_type override the global option values for each adaptation set.
288 For example, -adaptation_sets "id=0,seg_duration=2,frag_duration=1,frag_type=duration,streams=v id=1,seg_duration=2,frag_type=none,streams=a"
289 type_id marks an adaptation set as containing streams meant to be used for Trick Mode for the referenced adaptation set.
290 For example, -adaptation_sets "id=0,seg_duration=2,frag_type=none,streams=0 id=1,seg_duration=10,frag_type=none,trick_id=0,streams=1"
291 @item timeout @var{timeout}
292 Set timeout for socket I/O operations. Applicable only for HTTP output.
293 @item index_correction @var{index_correction}
294 Enable (1) or Disable (0) segment index correction logic. Applicable only when
295 @var{use_template} is enabled and @var{use_timeline} is disabled.
297 When enabled, the logic monitors the flow of segment indexes. If a streams's
298 segment index value is not at the expected real time position, then the logic
299 corrects that index value.
301 Typically this logic is needed in live streaming use cases. The network bandwidth
302 fluctuations are common during long run streaming. Each fluctuation can cause
303 the segment indexes fall behind the expected real time position.
304 @item format_options @var{options_list}
305 Set container format (mp4/webm) options using a @code{:} separated list of
306 key=value parameters. Values containing @code{:} special characters must be
309 @item global_sidx @var{global_sidx}
310 Write global SIDX atom. Applicable only for single file, mp4 output, non-streaming mode.
312 @item dash_segment_type @var{dash_segment_type}
316 If this flag is set, the dash segment files format will be selected based on the stream codec. This is the default mode.
319 If this flag is set, the dash segment files will be in in ISOBMFF format.
322 If this flag is set, the dash segment files will be in in WebM format.
325 @item ignore_io_errors @var{ignore_io_errors}
326 Ignore IO errors during open and write. Useful for long-duration runs with network output.
328 @item lhls @var{lhls}
329 Enable Low-latency HLS(LHLS). Adds #EXT-X-PREFETCH tag with current segment's URI.
330 Apple doesn't have an official spec for LHLS. Meanwhile hls.js player folks are
331 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
332 This option will also try to comply with the above open spec, till Apple's spec officially supports it.
333 Applicable only when @var{streaming} and @var{hls_playlist} options are enabled.
334 This is an experimental feature.
336 @item ldash @var{ldash}
337 Enable Low-latency Dash by constraining the presence and values of some elements.
339 @item master_m3u8_publish_rate @var{master_m3u8_publish_rate}
340 Publish master playlist repeatedly every after specified number of segment intervals.
342 @item -write_prft @var{write_prft}
343 Write Producer Reference Time elements on supported streams. This also enables writing
344 prft boxes in the underlying muxer. Applicable only when the @var{utc_url} option is enabled.
345 It's set to auto by default, in which case the muxer will attempt to enable it only in modes
348 @item -mpd_profile @var{mpd_profile}
349 Set one or more manifest profiles.
351 @item -http_opts @var{http_opts}
352 A :-separated list of key=value options to pass to the underlying HTTP
353 protocol. Applicable only for HTTP output.
355 @item -target_latency @var{target_latency}
356 Set an intended target latency in seconds (fractional value can be set) for serving. Applicable only when @var{streaming} and @var{write_prft} options are enabled.
357 This is an informative fields clients can use to measure the latency of the service.
364 Per-packet CRC (Cyclic Redundancy Check) testing format.
366 This muxer computes and prints the Adler-32 CRC for each audio
367 and video packet. By default audio frames are converted to signed
368 16-bit raw audio and video frames to raw video before computing the
371 The output of the muxer consists of a line for each audio and video
374 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
377 @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
382 For example to compute the CRC of the audio and video frames in
383 @file{INPUT}, converted to raw audio and video packets, and store it
384 in the file @file{out.crc}:
386 ffmpeg -i INPUT -f framecrc out.crc
389 To print the information to stdout, use the command:
391 ffmpeg -i INPUT -f framecrc -
394 With @command{ffmpeg}, you can select the output format to which the
395 audio and video frames are encoded before computing the CRC for each
396 packet by specifying the audio and video codec. For example, to
397 compute the CRC of each decoded input audio frame converted to PCM
398 unsigned 8-bit and of each decoded input video frame converted to
399 MPEG-2 video, use the command:
401 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
404 See also the @ref{crc} muxer.
409 Per-packet hash testing format.
411 This muxer computes and prints a cryptographic hash for each audio
412 and video packet. This can be used for packet-by-packet equality
413 checks without having to individually do a binary comparison on each.
415 By default audio frames are converted to signed 16-bit raw audio and
416 video frames to raw video before computing the hash, but the output
417 of explicit conversions to other codecs can also be used. It uses the
418 SHA-256 cryptographic hash function by default, but supports several
421 The output of the muxer consists of a line for each audio and video
424 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
427 @var{hash} is a hexadecimal number representing the computed hash
431 @item hash @var{algorithm}
432 Use the cryptographic hash function specified by the string @var{algorithm}.
433 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
434 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
435 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
436 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
442 To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
443 converted to raw audio and video packets, and store it in the file
446 ffmpeg -i INPUT -f framehash out.sha256
449 To print the information to stdout, using the MD5 hash function, use
452 ffmpeg -i INPUT -f framehash -hash md5 -
455 See also the @ref{hash} muxer.
460 Per-packet MD5 testing format.
462 This is a variant of the @ref{framehash} muxer. Unlike that muxer,
463 it defaults to using the MD5 hash function.
467 To compute the MD5 hash of the audio and video frames in @file{INPUT},
468 converted to raw audio and video packets, and store it in the file
471 ffmpeg -i INPUT -f framemd5 out.md5
474 To print the information to stdout, use the command:
476 ffmpeg -i INPUT -f framemd5 -
479 See also the @ref{framehash} and @ref{md5} muxers.
486 It accepts the following options:
490 Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
491 for looping indefinitely (default).
494 Force the delay (expressed in centiseconds) after the last frame. Each frame
495 ends with a delay until the next frame. The default is @code{-1}, which is a
496 special value to tell the muxer to re-use the previous delay. In case of a
497 loop, you might want to customize this value to mark a pause for instance.
500 For example, to encode a gif looping 10 times, with a 5 seconds delay between
503 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
506 Note 1: if you wish to extract the frames into separate GIF files, you need to
507 force the @ref{image2} muxer:
509 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
512 Note 2: the GIF format has a very large time base: the delay between two frames
513 can therefore not be smaller than one centi second.
520 This muxer computes and prints a cryptographic hash of all the input
521 audio and video frames. This can be used for equality checks without
522 having to do a complete binary comparison.
524 By default audio frames are converted to signed 16-bit raw audio and
525 video frames to raw video before computing the hash, but the output
526 of explicit conversions to other codecs can also be used. Timestamps
527 are ignored. It uses the SHA-256 cryptographic hash function by default,
528 but supports several other algorithms.
530 The output of the muxer consists of a single line of the form:
531 @var{algo}=@var{hash}, where @var{algo} is a short string representing
532 the hash function used, and @var{hash} is a hexadecimal number
533 representing the computed hash.
536 @item hash @var{algorithm}
537 Use the cryptographic hash function specified by the string @var{algorithm}.
538 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
539 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
540 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
541 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
547 To compute the SHA-256 hash of the input converted to raw audio and
548 video, and store it in the file @file{out.sha256}:
550 ffmpeg -i INPUT -f hash out.sha256
553 To print an MD5 hash to stdout use the command:
555 ffmpeg -i INPUT -f hash -hash md5 -
558 See also the @ref{framehash} muxer.
563 Apple HTTP Live Streaming muxer that segments MPEG-TS according to
564 the HTTP Live Streaming (HLS) specification.
566 It creates a playlist file, and one or more segment files. The output filename
567 specifies the playlist filename.
569 By default, the muxer creates a file for each segment produced. These files
570 have the same name as the playlist, followed by a sequential number and a
573 Make sure to require a closed GOP when encoding and to set the GOP
574 size to fit your segment time constraint.
576 For example, to convert an input file with @command{ffmpeg}:
578 ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
580 This example will produce the playlist, @file{out.m3u8}, and segment files:
581 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
583 See also the @ref{segment} muxer, which provides a more generic and
584 flexible implementation of a segmenter, and can be used to perform HLS
589 This muxer supports the following options:
592 @item hls_init_time @var{seconds}
593 Set the initial target segment length in seconds. Default value is @var{0}.
594 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
595 After the initial playlist is filled @command{ffmpeg} will cut segments
596 at duration equal to @code{hls_time}
598 @item hls_time @var{seconds}
599 Set the target segment length in seconds. Default value is 2.
600 Segment will be cut on the next key frame after this time has passed.
602 @item hls_list_size @var{size}
603 Set the maximum number of playlist entries. If set to 0 the list file
604 will contain all the segments. Default value is 5.
606 @item hls_delete_threshold @var{size}
607 Set the number of unreferenced segments to keep on disk before @code{hls_flags delete_segments}
608 deletes them. Increase this to allow continue clients to download segments which
609 were recently referenced in the playlist. Default value is 1, meaning segments older than
610 @code{hls_list_size+1} will be deleted.
612 @item hls_ts_options @var{options_list}
613 Set output format options using a :-separated list of key=value
614 parameters. Values containing @code{:} special characters must be
617 @item hls_wrap @var{wrap}
618 This is a deprecated option, you can use @code{hls_list_size}
619 and @code{hls_flags delete_segments} instead it
621 This option is useful to avoid to fill the disk with many segment
622 files, and limits the maximum number of segment files written to disk
626 @item hls_start_number_source
627 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
628 Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
629 segment and subtitle filenames. In any case, if @code{hls_flags append_list}
630 is set and read playlist sequence number is greater than the specified start sequence number,
631 then that value will be used as start value.
633 It accepts the following values:
637 @item generic (default)
638 Set the starting sequence numbers according to @var{start_number} option value.
641 The start number will be the seconds since epoch (1970-01-01 00:00:00)
644 The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
648 @item start_number @var{number}
649 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
650 when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
651 Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
654 @item hls_allow_cache @var{allowcache}
655 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
657 @item hls_base_url @var{baseurl}
658 Append @var{baseurl} to every entry in the playlist.
659 Useful to generate playlists with absolute paths.
661 Note that the playlist sequence number must be unique for each segment
662 and it is not to be confused with the segment filename sequence number
663 which can be cyclic, for example if the @option{wrap} option is
666 @item hls_segment_filename @var{filename}
667 Set the segment filename. Unless @code{hls_flags single_file} is set,
668 @var{filename} is used as a string format with the segment number:
670 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
672 This example will produce the playlist, @file{out.m3u8}, and segment files:
673 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
675 @var{filename} may contain full path or relative path specification,
676 but only the file name part without any path info will be contained in the m3u8 segment list.
677 Should a relative path be specified, the path of the created segment
678 files will be relative to the current working directory.
679 When strftime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
681 When @code{var_stream_map} is set with two or more variant streams, the
682 @var{filename} pattern must contain the string "%v", this string specifies
683 the position of variant stream index in the generated segment file names.
685 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
686 -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" \
687 -hls_segment_filename 'file_%v_%03d.ts' out_%v.m3u8
689 This example will produce the playlists segment file sets:
690 @file{file_0_000.ts}, @file{file_0_001.ts}, @file{file_0_002.ts}, etc. and
691 @file{file_1_000.ts}, @file{file_1_001.ts}, @file{file_1_002.ts}, etc.
693 The string "%v" may be present in the filename or in the last directory name
694 containing the file, but only in one of them. (Additionally, %v may appear multiple times in the last
695 sub-directory or filename.) If the string %v is present in the directory name, then
696 sub-directories are created after expanding the directory name pattern. This
697 enables creation of segments corresponding to different variant streams in
700 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
701 -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" \
702 -hls_segment_filename 'vs%v/file_%03d.ts' vs%v/out.m3u8
704 This example will produce the playlists segment file sets:
705 @file{vs0/file_000.ts}, @file{vs0/file_001.ts}, @file{vs0/file_002.ts}, etc. and
706 @file{vs1/file_000.ts}, @file{vs1/file_001.ts}, @file{vs1/file_002.ts}, etc.
709 Same as strftime option, will be deprecated.
712 Use strftime() on @var{filename} to expand the segment filename with localtime.
713 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
714 hls_flag and %%d will be the specifier.
716 ffmpeg -i in.nut -strftime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
718 This example will produce the playlist, @file{out.m3u8}, and segment files:
719 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
720 Note: On some systems/environments, the @code{%s} specifier is not available. See
721 @code{strftime()} documentation.
723 ffmpeg -i in.nut -strftime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
725 This example will produce the playlist, @file{out.m3u8}, and segment files:
726 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
728 @item use_localtime_mkdir
729 Same as strftime_mkdir option, will be deprecated .
732 Used together with -strftime_mkdir, it will create all subdirectories which
733 is expanded in @var{filename}.
735 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y%m%d/file-%Y%m%d-%s.ts' out.m3u8
737 This example will create a directory 201560215 (if it does not exist), and then
738 produce the playlist, @file{out.m3u8}, and segment files:
739 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
742 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y/%m/%d/file-%Y%m%d-%s.ts' out.m3u8
744 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
745 produce the playlist, @file{out.m3u8}, and segment files:
746 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
749 @item hls_key_info_file @var{key_info_file}
750 Use the information in @var{key_info_file} for segment encryption. The first
751 line of @var{key_info_file} specifies the key URI written to the playlist. The
752 key URL is used to access the encryption key during playback. The second line
753 specifies the path to the key file used to obtain the key during the encryption
754 process. The key file is read as a single packed array of 16 octets in binary
755 format. The optional third line specifies the initialization vector (IV) as a
756 hexadecimal string to be used instead of the segment sequence number (default)
757 for encryption. Changes to @var{key_info_file} will result in segment
758 encryption with the new key/IV and an entry in the playlist for the new key
759 URI/IV if @code{hls_flags periodic_rekey} is enabled.
761 Key info file format:
770 http://server/file.key
775 Example key file paths:
783 0123456789ABCDEF0123456789ABCDEF
786 Key info file example:
788 http://server/file.key
790 0123456789ABCDEF0123456789ABCDEF
793 Example shell script:
797 openssl rand 16 > file.key
798 echo $BASE_URL/file.key > file.keyinfo
799 echo file.key >> file.keyinfo
800 echo $(openssl rand -hex 16) >> file.keyinfo
801 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
802 -hls_key_info_file file.keyinfo out.m3u8
805 @item -hls_enc @var{enc}
806 Enable (1) or disable (0) the AES128 encryption.
807 When enabled every segment generated is encrypted and the encryption key
808 is saved as @var{playlist name}.key.
810 @item -hls_enc_key @var{key}
811 Hex-coded 16byte key to encrypt the segments, by default it
812 is randomly generated.
814 @item -hls_enc_key_url @var{keyurl}
815 If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
818 @item -hls_enc_iv @var{iv}
819 Hex-coded 16byte initialization vector for every segment instead
820 of the autogenerated ones.
822 @item hls_segment_type @var{flags}
827 Output segment files in MPEG-2 Transport Stream format. This is
828 compatible with all HLS versions.
831 Output segment files in fragmented MP4 format, similar to MPEG-DASH.
832 fmp4 files may be used in HLS version 7 and above.
836 @item hls_fmp4_init_filename @var{filename}
837 Set filename to the fragment files header file, default filename is @file{init.mp4}.
839 When @code{var_stream_map} is set with two or more variant streams, the
840 @var{filename} pattern must contain the string "%v", this string specifies
841 the position of variant stream index in the generated init file names.
842 The string "%v" may be present in the filename or in the last directory name
843 containing the file. If the string is present in the directory name, then
844 sub-directories are created after expanding the directory name pattern. This
845 enables creation of init files corresponding to different variant streams in
848 @item hls_flags @var{flags}
853 If this flag is set, the muxer will store all segments in a single MPEG-TS
854 file, and will use byte ranges in the playlist. HLS playlists generated with
855 this way will have the version number 4.
858 ffmpeg -i in.nut -hls_flags single_file out.m3u8
860 Will produce the playlist, @file{out.m3u8}, and a single segment file,
863 @item delete_segments
864 Segment files removed from the playlist are deleted after a period of time
865 equal to the duration of the segment plus the duration of the playlist.
868 Append new segments into the end of old segment list,
869 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
871 @item round_durations
872 Round the duration info in the playlist file segment info to integer
873 values, instead of using floating point.
876 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
877 first segment's information.
880 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
883 The file specified by @code{hls_key_info_file} will be checked periodically and
884 detect updates to the encryption info. Be sure to replace this file atomically,
885 including the file containing the AES encryption key.
887 @item independent_segments
888 Add the @code{#EXT-X-INDEPENDENT-SEGMENTS} to playlists that has video segments
889 and when all the segments of that playlist are guaranteed to start with a Key frame.
892 Add the @code{#EXT-X-I-FRAMES-ONLY} to playlists that has video segments
893 and can play only I-frames in the @code{#EXT-X-BYTERANGE} mode.
896 Allow segments to start on frames other than keyframes. This improves
897 behavior on some players when the time between keyframes is inconsistent,
898 but may make things worse on others, and can cause some oddities during
899 seeking. This flag should be used with the @code{hls_time} option.
901 @item program_date_time
902 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
904 @item second_level_segment_index
905 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
906 besides date/time values when strftime is on.
907 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
909 @item second_level_segment_size
910 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
911 expression besides date/time values when strftime is on.
912 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
914 @item second_level_segment_duration
915 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
916 expression besides date/time values when strftime is on.
917 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
920 ffmpeg -i sample.mpeg \
921 -f hls -hls_time 3 -hls_list_size 5 \
922 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
923 -strftime 1 -strftime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
925 This will produce segments like this:
926 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
929 Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
930 serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
931 before they have been added to the m3u8 playlist. This flag also affects how m3u8 playlist files are created.
932 If this flag is set, all playlist files will written into temporary file and renamed after they are complete, similarly as segments are handled.
933 But playlists with @code{file} protocol and with type (@code{hls_playlist_type}) other than @code{vod}
934 are always written into temporary file regardless of this flag. Master playlist files (@code{master_pl_name}), if any, with @code{file} protocol,
935 are always written into temporary file regardless of this flag if @code{master_pl_publish_rate} value is other than zero.
939 @item hls_playlist_type event
940 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
941 @option{hls_list_size} to 0; the playlist can only be appended to.
943 @item hls_playlist_type vod
944 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
945 @option{hls_list_size} to 0; the playlist must not change.
948 Use the given HTTP method to create the hls files.
950 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
952 This example will upload all the mpegts segment files to the HTTP
953 server using the HTTP PUT method, and update the m3u8 files every
954 @code{refresh} times using the same method.
955 Note that the HTTP server must support the given method for uploading
958 @item http_user_agent
959 Override User-Agent field in HTTP header. Applicable only for HTTP output.
962 Map string which specifies how to group the audio, video and subtitle streams
963 into different variant streams. The variant stream groups are separated
965 Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
966 the keys to specify audio, video and subtitle streams respectively.
967 Allowed values are 0 to 9 (limited just based on practical usage).
969 When there are two or more variant streams, the output filename pattern must
970 contain the string "%v", this string specifies the position of variant stream
971 index in the output media playlist filenames. The string "%v" may be present in
972 the filename or in the last directory name containing the file. If the string is
973 present in the directory name, then sub-directories are created after expanding
974 the directory name pattern. This enables creation of variant streams in
978 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
979 -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" \
980 http://example.com/live/out_%v.m3u8
982 This example creates two hls variant streams. The first variant stream will
983 contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
984 second variant stream will contain video stream of bitrate 256k and audio
985 stream of bitrate 32k. Here, two media playlist with file names out_0.m3u8 and
986 out_1.m3u8 will be created. If you want something meaningful text instead of indexes
987 in result names, you may specify names for each or some of the variants
988 as in the following example.
992 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
993 -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" \
994 http://example.com/live/out_%v.m3u8
997 This example creates two hls variant streams as in the previous one.
998 But here, the two media playlist with file names out_my_hd.m3u8 and
999 out_my_sd.m3u8 will be created.
1002 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
1003 -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
1004 http://example.com/live/out_%v.m3u8
1006 This example creates three hls variant streams. The first variant stream will
1007 be a video only stream with video bitrate 1000k, the second variant stream will
1008 be an audio only stream with bitrate 64k and the third variant stream will be a
1009 video only stream with bitrate 256k. Here, three media playlist with file names
1010 out_0.m3u8, out_1.m3u8 and out_2.m3u8 will be created.
1012 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1013 -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" \
1014 http://example.com/live/vs_%v/out.m3u8
1016 This example creates the variant streams in subdirectories. Here, the first
1017 media playlist is created at @file{http://example.com/live/vs_0/out.m3u8} and
1018 the second one at @file{http://example.com/live/vs_1/out.m3u8}.
1020 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k \
1021 -map 0:a -map 0:a -map 0:v -map 0:v -f hls \
1022 -var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
1023 -master_pl_name master.m3u8 \
1024 http://example.com/live/out_%v.m3u8
1026 This example creates two audio only and two video only variant streams. In
1027 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1028 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1029 and they are mapped to the two video only variant streams with audio group names
1030 'aud_low' and 'aud_high'.
1032 By default, a single hls variant containing all the encoded streams is created.
1035 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
1036 -map 0:a -map 0:a -map 0:v -f hls \
1037 -var_stream_map "a:0,agroup:aud_low,default:yes a:1,agroup:aud_low v:0,agroup:aud_low" \
1038 -master_pl_name master.m3u8 \
1039 http://example.com/live/out_%v.m3u8
1041 This example creates two audio only and one video only variant streams. In
1042 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1043 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1044 and they are mapped to the one video only variant streams with audio group name
1045 'aud_low', and the audio group have default stat is NO or YES.
1047 By default, a single hls variant containing all the encoded streams is created.
1050 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
1051 -map 0:a -map 0:a -map 0:v -f hls \
1052 -var_stream_map "a:0,agroup:aud_low,default:yes,language:ENG a:1,agroup:aud_low,language:CHN v:0,agroup:aud_low" \
1053 -master_pl_name master.m3u8 \
1054 http://example.com/live/out_%v.m3u8
1056 This example creates two audio only and one video only variant streams. In
1057 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1058 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1059 and they are mapped to the one video only variant streams with audio group name
1060 'aud_low', and the audio group have default stat is NO or YES, and one audio
1061 have and language is named ENG, the other audio language is named CHN.
1063 By default, a single hls variant containing all the encoded streams is created.
1066 Map string which specifies different closed captions groups and their
1067 attributes. The closed captions stream groups are separated by space.
1068 Expected string format is like this
1069 "ccgroup:<group name>,instreamid:<INSTREAM-ID>,language:<language code> ....".
1070 'ccgroup' and 'instreamid' are mandatory attributes. 'language' is an optional
1072 The closed captions groups configured using this option are mapped to different
1073 variant streams by providing the same 'ccgroup' name in the
1074 @code{var_stream_map} string. If @code{var_stream_map} is not set, then the
1075 first available ccgroup in @code{cc_stream_map} is mapped to the output variant
1076 stream. The examples for these two use cases are given below.
1079 ffmpeg -re -i in.ts -b:v 1000k -b:a 64k -a53cc 1 -f hls \
1080 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en" \
1081 -master_pl_name master.m3u8 \
1082 http://example.com/live/out.m3u8
1084 This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=CLOSED-CAPTIONS} in
1085 the master playlist with group name 'cc', language 'en' (english) and
1086 INSTREAM-ID 'CC1'. Also, it adds @code{CLOSED-CAPTIONS} attribute with group
1087 name 'cc' for the output variant stream.
1089 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1090 -a53cc:0 1 -a53cc:1 1\
1091 -map 0:v -map 0:a -map 0:v -map 0:a -f hls \
1092 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en ccgroup:cc,instreamid:CC2,language:sp" \
1093 -var_stream_map "v:0,a:0,ccgroup:cc v:1,a:1,ccgroup:cc" \
1094 -master_pl_name master.m3u8 \
1095 http://example.com/live/out_%v.m3u8
1097 This example adds two @code{#EXT-X-MEDIA} tags with @code{TYPE=CLOSED-CAPTIONS} in
1098 the master playlist for the INSTREAM-IDs 'CC1' and 'CC2'. Also, it adds
1099 @code{CLOSED-CAPTIONS} attribute with group name 'cc' for the two output variant
1102 @item master_pl_name
1103 Create HLS master playlist with the given name.
1106 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
1108 This example creates HLS master playlist with name master.m3u8 and it is
1109 published at http://example.com/live/
1111 @item master_pl_publish_rate
1112 Publish master play list repeatedly every after specified number of segment intervals.
1115 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
1116 -hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
1119 This example creates HLS master playlist with name master.m3u8 and keep
1120 publishing it repeatedly every after 30 segments i.e. every after 60s.
1122 @item http_persistent
1123 Use persistent HTTP connections. Applicable only for HTTP output.
1126 Set timeout for socket I/O operations. Applicable only for HTTP output.
1128 @item -ignore_io_errors
1129 Ignore IO errors during open, write and delete. Useful for long-duration runs with network output.
1132 Set custom HTTP headers, can override built in default headers. Applicable only for HTTP output.
1141 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
1145 Size cannot exceed 256 pixels in any dimension
1148 Only BMP and PNG images can be stored
1151 If a BMP image is used, it must be one of the following pixel formats:
1153 BMP Bit Depth FFmpeg Pixel Format
1163 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
1166 If a PNG image is used, it must use the rgba pixel format
1174 The image file muxer writes video frames to image files.
1176 The output filenames are specified by a pattern, which can be used to
1177 produce sequentially numbered series of files.
1178 The pattern may contain the string "%d" or "%0@var{N}d", this string
1179 specifies the position of the characters representing a numbering in
1180 the filenames. If the form "%0@var{N}d" is used, the string
1181 representing the number in each filename is 0-padded to @var{N}
1182 digits. The literal character '%' can be specified in the pattern with
1185 If the pattern contains "%d" or "%0@var{N}d", the first filename of
1186 the file list specified will contain the number 1, all the following
1187 numbers will be sequential.
1189 The pattern may contain a suffix which is used to automatically
1190 determine the format of the image files to write.
1192 For example the pattern "img-%03d.bmp" will specify a sequence of
1193 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
1194 @file{img-010.bmp}, etc.
1195 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
1196 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
1199 The image muxer supports the .Y.U.V image file format. This format is
1200 special in that that each image frame consists of three files, for
1201 each of the YUV420P components. To read or write this image file format,
1202 specify the name of the '.Y' file. The muxer will automatically open the
1203 '.U' and '.V' files as required.
1209 If set to 1, expand the filename with pts from pkt->pts.
1213 Start the sequence from the specified number. Default value is 1.
1216 If set to 1, the filename will always be interpreted as just a
1217 filename, not a pattern, and the corresponding file will be continuously
1218 overwritten with new images. Default value is 0.
1221 If set to 1, expand the filename with date and time information from
1222 @code{strftime()}. Default value is 0.
1224 @item protocol_opts @var{options_list}
1225 Set protocol options as a :-separated list of key=value parameters. Values
1226 containing the @code{:} special character must be escaped.
1230 @subsection Examples
1232 The following example shows how to use @command{ffmpeg} for creating a
1233 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
1234 taking one image every second from the input video:
1236 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
1239 Note that with @command{ffmpeg}, if the format is not specified with the
1240 @code{-f} option and the output filename specifies an image file
1241 format, the image2 muxer is automatically selected, so the previous
1242 command can be written as:
1244 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
1247 Note also that the pattern must not necessarily contain "%d" or
1248 "%0@var{N}d", for example to create a single image file
1249 @file{img.jpeg} from the start of the input video you can employ the command:
1251 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
1254 The @option{strftime} option allows you to expand the filename with
1255 date and time information. Check the documentation of
1256 the @code{strftime()} function for the syntax.
1258 For example to generate image files from the @code{strftime()}
1259 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
1262 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
1265 You can set the file name with current frame's PTS:
1267 ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
1270 A more complex example is to publish contents of your desktop directly to a
1271 WebDAV server every second:
1273 ffmpeg -f x11grab -framerate 1 -i :0.0 -q:v 6 -update 1 -protocol_opts method=PUT http://example.com/desktop.jpg
1278 Matroska container muxer.
1280 This muxer implements the matroska and webm container specs.
1282 @subsection Metadata
1284 The recognized metadata settings in this muxer are:
1288 Set title name provided to a single track.
1291 Specify the language of the track in the Matroska languages form.
1293 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
1294 639-2/B) form (like "fre" for French), or a language code mixed with a
1295 country code for specialities in languages (like "fre-ca" for Canadian
1299 Set stereo 3D video layout of two views in a single video track.
1301 The following values are recognized:
1306 Both views are arranged side by side, Left-eye view is on the left
1308 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
1310 Both views are arranged in top-bottom orientation, Left-eye view is on top
1311 @item checkerboard_rl
1312 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
1313 @item checkerboard_lr
1314 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
1315 @item row_interleaved_rl
1316 Each view is constituted by a row based interleaving, Right-eye view is first row
1317 @item row_interleaved_lr
1318 Each view is constituted by a row based interleaving, Left-eye view is first row
1319 @item col_interleaved_rl
1320 Both views are arranged in a column based interleaving manner, Right-eye view is first column
1321 @item col_interleaved_lr
1322 Both views are arranged in a column based interleaving manner, Left-eye view is first column
1323 @item anaglyph_cyan_red
1324 All frames are in anaglyph format viewable through red-cyan filters
1326 Both views are arranged side by side, Right-eye view is on the left
1327 @item anaglyph_green_magenta
1328 All frames are in anaglyph format viewable through green-magenta filters
1330 Both eyes laced in one Block, Left-eye view is first
1332 Both eyes laced in one Block, Right-eye view is first
1336 For example a 3D WebM clip can be created using the following command line:
1338 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
1343 This muxer supports the following options:
1346 @item reserve_index_space
1347 By default, this muxer writes the index for seeking (called cues in Matroska
1348 terms) at the end of the file, because it cannot know in advance how much space
1349 to leave for the index at the beginning of the file. However for some use cases
1350 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
1351 index at the beginning of the file.
1353 If this option is set to a non-zero value, the muxer will reserve a given amount
1354 of space in the file header and then try to write the cues there when the muxing
1355 finishes. If the available space does not suffice, muxing will fail. A safe size
1356 for most use cases should be about 50kB per hour of video.
1358 Note that cues are only written if the output is seekable and this option will
1359 have no effect if it is not.
1367 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
1368 defaults to using the MD5 hash function.
1370 @subsection Examples
1372 To compute the MD5 hash of the input converted to raw
1373 audio and video, and store it in the file @file{out.md5}:
1375 ffmpeg -i INPUT -f md5 out.md5
1378 You can print the MD5 to stdout with the command:
1380 ffmpeg -i INPUT -f md5 -
1383 See also the @ref{hash} and @ref{framemd5} muxers.
1385 @section mov, mp4, ismv
1387 MOV/MP4/ISMV (Smooth Streaming) muxer.
1389 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
1390 file has all the metadata about all packets stored in one location
1391 (written at the end of the file, it can be moved to the start for
1392 better playback by adding @var{faststart} to the @var{movflags}, or
1393 using the @command{qt-faststart} tool). A fragmented
1394 file consists of a number of fragments, where packets and metadata
1395 about these packets are stored together. Writing a fragmented
1396 file has the advantage that the file is decodable even if the
1397 writing is interrupted (while a normal MOV/MP4 is undecodable if
1398 it is not properly finished), and it requires less memory when writing
1399 very long files (since writing normal MOV/MP4 files stores info about
1400 every single packet in memory until the file is closed). The downside
1401 is that it is less compatible with other applications.
1405 Fragmentation is enabled by setting one of the AVOptions that define
1406 how to cut the file into fragments:
1409 @item -moov_size @var{bytes}
1410 Reserves space for the moov atom at the beginning of the file instead of placing the
1411 moov atom at the end. If the space reserved is insufficient, muxing will fail.
1412 @item -movflags frag_keyframe
1413 Start a new fragment at each video keyframe.
1414 @item -frag_duration @var{duration}
1415 Create fragments that are @var{duration} microseconds long.
1416 @item -frag_size @var{size}
1417 Create fragments that contain up to @var{size} bytes of payload data.
1418 @item -movflags frag_custom
1419 Allow the caller to manually choose when to cut fragments, by
1420 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
1421 the packets written so far. (This is only useful with other
1422 applications integrating libavformat, not from @command{ffmpeg}.)
1423 @item -min_frag_duration @var{duration}
1424 Don't create fragments that are shorter than @var{duration} microseconds long.
1427 If more than one condition is specified, fragments are cut when
1428 one of the specified conditions is fulfilled. The exception to this is
1429 @code{-min_frag_duration}, which has to be fulfilled for any of the other
1430 conditions to apply.
1432 Additionally, the way the output file is written can be adjusted
1433 through a few other options:
1436 @item -movflags empty_moov
1437 Write an initial moov atom directly at the start of the file, without
1438 describing any samples in it. Generally, an mdat/moov pair is written
1439 at the start of the file, as a normal MOV/MP4 file, containing only
1440 a short portion of the file. With this option set, there is no initial
1441 mdat atom, and the moov atom only describes the tracks but has
1444 This option is implicitly set when writing ismv (Smooth Streaming) files.
1445 @item -movflags separate_moof
1446 Write a separate moof (movie fragment) atom for each track. Normally,
1447 packets for all tracks are written in a moof atom (which is slightly
1448 more efficient), but with this option set, the muxer writes one moof/mdat
1449 pair for each track, making it easier to separate tracks.
1451 This option is implicitly set when writing ismv (Smooth Streaming) files.
1452 @item -movflags skip_sidx
1453 Skip writing of sidx atom. When bitrate overhead due to sidx atom is high,
1454 this option could be used for cases where sidx atom is not mandatory.
1455 When global_sidx flag is enabled, this option will be ignored.
1456 @item -movflags faststart
1457 Run a second pass moving the index (moov atom) to the beginning of the file.
1458 This operation can take a while, and will not work in various situations such
1459 as fragmented output, thus it is not enabled by default.
1460 @item -movflags rtphint
1461 Add RTP hinting tracks to the output file.
1462 @item -movflags disable_chpl
1463 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
1464 and a QuickTime chapter track are written to the file. With this option
1465 set, only the QuickTime chapter track will be written. Nero chapters can
1466 cause failures when the file is reprocessed with certain tagging programs, like
1467 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
1468 @item -movflags omit_tfhd_offset
1469 Do not write any absolute base_data_offset in tfhd atoms. This avoids
1470 tying fragments to absolute byte positions in the file/streams.
1471 @item -movflags default_base_moof
1472 Similarly to the omit_tfhd_offset, this flag avoids writing the
1473 absolute base_data_offset field in tfhd atoms, but does so by using
1474 the new default-base-is-moof flag instead. This flag is new from
1475 14496-12:2012. This may make the fragments easier to parse in certain
1476 circumstances (avoiding basing track fragment location calculations
1477 on the implicit end of the previous track fragment).
1479 Specify @code{on} to force writing a timecode track, @code{off} to disable it
1480 and @code{auto} to write a timecode track only for mov and mp4 output (default).
1481 @item -movflags negative_cts_offsets
1482 Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
1483 be negative. This enables the initial sample to have DTS/CTS of zero, and
1484 reduces the need for edit lists for some cases such as video tracks with
1485 B-frames. Additionally, eases conformance with the DASH-IF interoperability
1488 This option is implicitly set when writing ismv (Smooth Streaming) files.
1490 Write producer time reference box (PRFT) with a specified time source for the
1491 NTP field in the PRFT box. Set value as @samp{wallclock} to specify timesource
1492 as wallclock time and @samp{pts} to specify timesource as input packets' PTS
1495 Setting value to @samp{pts} is applicable only for a live encoding use case,
1496 where PTS values are set as as wallclock time at the source. For example, an
1497 encoding use case with decklink capture source where @option{video_pts} and
1498 @option{audio_pts} are set to @samp{abs_wallclock}.
1503 Smooth Streaming content can be pushed in real time to a publishing
1504 point on IIS with this muxer. Example:
1506 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
1511 The MP3 muxer writes a raw MP3 stream with the following optional features:
1514 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
1515 2.4 are supported, the @code{id3v2_version} private option controls which one is
1516 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
1519 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
1520 The pictures are supplied to the muxer in form of a video stream with a single
1521 packet. There can be any number of those streams, each will correspond to a
1522 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
1523 to APIC @var{description} and @var{picture type} respectively. See
1524 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
1526 Note that the APIC frames must be written at the beginning, so the muxer will
1527 buffer the audio frames until it gets all the pictures. It is therefore advised
1528 to provide the pictures as soon as possible to avoid excessive buffering.
1531 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
1532 default, but will be written only if the output is seekable. The
1533 @code{write_xing} private option can be used to disable it. The frame contains
1534 various information that may be useful to the decoder, like the audio duration
1538 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1539 enabled with the @code{write_id3v1} private option, but as its capabilities are
1540 very limited, its usage is not recommended.
1545 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1547 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1550 To attach a picture to an mp3 file select both the audio and the picture stream
1553 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1554 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1557 Write a "clean" MP3 without any extra features:
1559 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1564 MPEG transport stream muxer.
1566 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1568 The recognized metadata settings in mpegts muxer are @code{service_provider}
1569 and @code{service_name}. If they are not set the default for
1570 @code{service_provider} is @samp{FFmpeg} and the default for
1571 @code{service_name} is @samp{Service01}.
1575 The muxer options are:
1578 @item mpegts_transport_stream_id @var{integer}
1579 Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
1580 Default is @code{0x0001}.
1582 @item mpegts_original_network_id @var{integer}
1583 Set the @samp{original_network_id}. This is unique identifier of a
1584 network in DVB. Its main use is in the unique identification of a service
1585 through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
1588 @item mpegts_service_id @var{integer}
1589 Set the @samp{service_id}, also known as program in DVB. Default is
1592 @item mpegts_service_type @var{integer}
1593 Set the program @samp{service_type}. Default is @code{digital_tv}.
1594 Accepts the following options:
1597 Any hexadecimal value between @code{0x01} and @code{0xff} as defined in
1602 Digital Radio service.
1605 @item advanced_codec_digital_radio
1606 Advanced Codec Digital Radio service.
1607 @item mpeg2_digital_hdtv
1608 MPEG2 Digital HDTV service.
1609 @item advanced_codec_digital_sdtv
1610 Advanced Codec Digital SDTV service.
1611 @item advanced_codec_digital_hdtv
1612 Advanced Codec Digital HDTV service.
1615 @item mpegts_pmt_start_pid @var{integer}
1616 Set the first PID for PMTs. Default is @code{0x1000}, minimum is @code{0x0020},
1617 maximum is @code{0x1ffa}.
1619 @item mpegts_start_pid @var{integer}
1620 Set the first PID for elementary streams. Default is @code{0x0100}, minimum is
1621 @code{0x0020}, maximum is @code{0x1ffa}.
1623 @item mpegts_m2ts_mode @var{boolean}
1624 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
1627 @item muxrate @var{integer}
1628 Set a constant muxrate. Default is VBR.
1630 @item pes_payload_size @var{integer}
1631 Set minimum PES packet payload in bytes. Default is @code{2930}.
1633 @item mpegts_flags @var{flags}
1634 Set mpegts flags. Accepts the following options:
1636 @item resend_headers
1637 Reemit PAT/PMT before writing the next packet.
1639 Use LATM packetization for AAC.
1640 @item pat_pmt_at_frames
1641 Reemit PAT and PMT at each video frame.
1643 Conform to System B (DVB) instead of System A (ATSC).
1644 @item initial_discontinuity
1645 Mark the initial packet of each stream as discontinuity.
1648 @item mpegts_copyts @var{boolean}
1649 Preserve original timestamps, if value is set to @code{1}. Default value
1650 is @code{-1}, which results in shifting timestamps so that they start from 0.
1652 @item omit_video_pes_length @var{boolean}
1653 Omit the PES packet length for video packets. Default is @code{1} (true).
1655 @item pcr_period @var{integer}
1656 Override the default PCR retransmission time in milliseconds. Default is
1657 @code{-1} which means that the PCR interval will be determined automatically:
1658 20 ms is used for CBR streams, the highest multiple of the frame duration which
1659 is less than 100 ms is used for VBR streams.
1661 @item pat_period @var{duration}
1662 Maximum time in seconds between PAT/PMT tables. Default is @code{0.1}.
1664 @item sdt_period @var{duration}
1665 Maximum time in seconds between SDT tables. Default is @code{0.5}.
1667 @item tables_version @var{integer}
1668 Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
1669 This option allows updating stream structure so that standard consumer may
1670 detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
1671 usage) or restart @command{ffmpeg} instance, cyclically changing
1672 @option{tables_version} value:
1675 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1676 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1678 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1679 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1680 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1688 ffmpeg -i file.mpg -c copy \
1689 -mpegts_original_network_id 0x1122 \
1690 -mpegts_transport_stream_id 0x3344 \
1691 -mpegts_service_id 0x5566 \
1692 -mpegts_pmt_start_pid 0x1500 \
1693 -mpegts_start_pid 0x150 \
1694 -metadata service_provider="Some provider" \
1695 -metadata service_name="Some Channel" \
1699 @section mxf, mxf_d10, mxf_opatom
1705 The muxer options are:
1708 @item store_user_comments @var{bool}
1709 Set if user comments should be stored if available or never.
1710 IRT D-10 does not allow user comments. The default is thus to write them for
1711 mxf and mxf_opatom but not for mxf_d10
1718 This muxer does not generate any output file, it is mainly useful for
1719 testing or benchmarking purposes.
1721 For example to benchmark decoding with @command{ffmpeg} you can use the
1724 ffmpeg -benchmark -i INPUT -f null out.null
1727 Note that the above command does not read or write the @file{out.null}
1728 file, but specifying the output file is required by the @command{ffmpeg}
1731 Alternatively you can write the command as:
1733 ffmpeg -benchmark -i INPUT -f null -
1739 @item -syncpoints @var{flags}
1740 Change the syncpoint usage in nut:
1742 @item @var{default} use the normal low-overhead seeking aids.
1743 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1744 Use of this option is not recommended, as the resulting files are very damage
1745 sensitive and seeking is not possible. Also in general the overhead from
1746 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1747 all growing data tables, allowing to mux endless streams with limited memory
1748 and without these disadvantages.
1749 @item @var{timestamped} extend the syncpoint with a wallclock field.
1751 The @var{none} and @var{timestamped} flags are experimental.
1752 @item -write_index @var{bool}
1753 Write index at the end, the default is to write an index.
1757 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1762 Ogg container muxer.
1765 @item -page_duration @var{duration}
1766 Preferred page duration, in microseconds. The muxer will attempt to create
1767 pages that are approximately @var{duration} microseconds long. This allows the
1768 user to compromise between seek granularity and container overhead. The default
1769 is 1 second. A value of 0 will fill all segments, making pages as large as
1770 possible. A value of 1 will effectively use 1 packet-per-page in most
1771 situations, giving a small seek granularity at the cost of additional container
1773 @item -serial_offset @var{value}
1774 Serial value from which to set the streams serial number.
1775 Setting it to different and sufficiently large values ensures that the produced
1776 ogg files can be safely chained.
1781 @section segment, stream_segment, ssegment
1783 Basic stream segmenter.
1785 This muxer outputs streams to a number of separate files of nearly
1786 fixed duration. Output filename pattern can be set in a fashion
1787 similar to @ref{image2}, or by using a @code{strftime} template if
1788 the @option{strftime} option is enabled.
1790 @code{stream_segment} is a variant of the muxer used to write to
1791 streaming output formats, i.e. which do not require global headers,
1792 and is recommended for outputting e.g. to MPEG transport stream segments.
1793 @code{ssegment} is a shorter alias for @code{stream_segment}.
1795 Every segment starts with a keyframe of the selected reference stream,
1796 which is set through the @option{reference_stream} option.
1798 Note that if you want accurate splitting for a video file, you need to
1799 make the input key frames correspond to the exact splitting times
1800 expected by the segmenter, or the segment muxer will start the new
1801 segment with the key frame found next after the specified start
1804 The segment muxer works best with a single constant frame rate video.
1806 Optionally it can generate a list of the created segments, by setting
1807 the option @var{segment_list}. The list type is specified by the
1808 @var{segment_list_type} option. The entry filenames in the segment
1809 list are set by default to the basename of the corresponding segment
1812 See also the @ref{hls} muxer, which provides a more specific
1813 implementation for HLS segmentation.
1817 The segment muxer supports the following options:
1820 @item increment_tc @var{1|0}
1821 if set to @code{1}, increment timecode between each segment
1822 If this is selected, the input need to have
1823 a timecode in the first video stream. Default value is
1826 @item reference_stream @var{specifier}
1827 Set the reference stream, as specified by the string @var{specifier}.
1828 If @var{specifier} is set to @code{auto}, the reference is chosen
1829 automatically. Otherwise it must be a stream specifier (see the ``Stream
1830 specifiers'' chapter in the ffmpeg manual) which specifies the
1831 reference stream. The default value is @code{auto}.
1833 @item segment_format @var{format}
1834 Override the inner container format, by default it is guessed by the filename
1837 @item segment_format_options @var{options_list}
1838 Set output format options using a :-separated list of key=value
1839 parameters. Values containing the @code{:} special character must be
1842 @item segment_list @var{name}
1843 Generate also a listfile named @var{name}. If not specified no
1844 listfile is generated.
1846 @item segment_list_flags @var{flags}
1847 Set flags affecting the segment list generation.
1849 It currently supports the following flags:
1852 Allow caching (only affects M3U8 list files).
1855 Allow live-friendly file generation.
1858 @item segment_list_size @var{size}
1859 Update the list file so that it contains at most @var{size}
1860 segments. If 0 the list file will contain all the segments. Default
1863 @item segment_list_entry_prefix @var{prefix}
1864 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1865 By default no prefix is applied.
1867 @item segment_list_type @var{type}
1868 Select the listing format.
1870 The following values are recognized:
1873 Generate a flat list for the created segments, one segment per line.
1876 Generate a list for the created segments, one segment per line,
1877 each line matching the format (comma-separated values):
1879 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1882 @var{segment_filename} is the name of the output file generated by the
1883 muxer according to the provided pattern. CSV escaping (according to
1884 RFC4180) is applied if required.
1886 @var{segment_start_time} and @var{segment_end_time} specify
1887 the segment start and end time expressed in seconds.
1889 A list file with the suffix @code{".csv"} or @code{".ext"} will
1890 auto-select this format.
1892 @samp{ext} is deprecated in favor or @samp{csv}.
1895 Generate an ffconcat file for the created segments. The resulting file
1896 can be read using the FFmpeg @ref{concat} demuxer.
1898 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1899 auto-select this format.
1902 Generate an extended M3U8 file, version 3, compliant with
1903 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1905 A list file with the suffix @code{".m3u8"} will auto-select this format.
1908 If not specified the type is guessed from the list file name suffix.
1910 @item segment_time @var{time}
1911 Set segment duration to @var{time}, the value must be a duration
1912 specification. Default value is "2". See also the
1913 @option{segment_times} option.
1915 Note that splitting may not be accurate, unless you force the
1916 reference stream key-frames at the given time. See the introductory
1917 notice and the examples below.
1919 @item segment_atclocktime @var{1|0}
1920 If set to "1" split at regular clock time intervals starting from 00:00
1921 o'clock. The @var{time} value specified in @option{segment_time} is
1922 used for setting the length of the splitting interval.
1924 For example with @option{segment_time} set to "900" this makes it possible
1925 to create files at 12:00 o'clock, 12:15, 12:30, etc.
1927 Default value is "0".
1929 @item segment_clocktime_offset @var{duration}
1930 Delay the segment splitting times with the specified duration when using
1931 @option{segment_atclocktime}.
1933 For example with @option{segment_time} set to "900" and
1934 @option{segment_clocktime_offset} set to "300" this makes it possible to
1935 create files at 12:05, 12:20, 12:35, etc.
1937 Default value is "0".
1939 @item segment_clocktime_wrap_duration @var{duration}
1940 Force the segmenter to only start a new segment if a packet reaches the muxer
1941 within the specified duration after the segmenting clock time. This way you
1942 can make the segmenter more resilient to backward local time jumps, such as
1943 leap seconds or transition to standard time from daylight savings time.
1945 Default is the maximum possible duration which means starting a new segment
1946 regardless of the elapsed time since the last clock time.
1948 @item segment_time_delta @var{delta}
1949 Specify the accuracy time when selecting the start time for a
1950 segment, expressed as a duration specification. Default value is "0".
1952 When delta is specified a key-frame will start a new segment if its
1953 PTS satisfies the relation:
1955 PTS >= start_time - time_delta
1958 This option is useful when splitting video content, which is always
1959 split at GOP boundaries, in case a key frame is found just before the
1960 specified split time.
1962 In particular may be used in combination with the @file{ffmpeg} option
1963 @var{force_key_frames}. The key frame times specified by
1964 @var{force_key_frames} may not be set accurately because of rounding
1965 issues, with the consequence that a key frame time may result set just
1966 before the specified time. For constant frame rate videos a value of
1967 1/(2*@var{frame_rate}) should address the worst case mismatch between
1968 the specified time and the time set by @var{force_key_frames}.
1970 @item segment_times @var{times}
1971 Specify a list of split points. @var{times} contains a list of comma
1972 separated duration specifications, in increasing order. See also
1973 the @option{segment_time} option.
1975 @item segment_frames @var{frames}
1976 Specify a list of split video frame numbers. @var{frames} contains a
1977 list of comma separated integer numbers, in increasing order.
1979 This option specifies to start a new segment whenever a reference
1980 stream key frame is found and the sequential number (starting from 0)
1981 of the frame is greater or equal to the next value in the list.
1983 @item segment_wrap @var{limit}
1984 Wrap around segment index once it reaches @var{limit}.
1986 @item segment_start_number @var{number}
1987 Set the sequence number of the first segment. Defaults to @code{0}.
1989 @item strftime @var{1|0}
1990 Use the @code{strftime} function to define the name of the new
1991 segments to write. If this is selected, the output segment name must
1992 contain a @code{strftime} function template. Default value is
1995 @item break_non_keyframes @var{1|0}
1996 If enabled, allow segments to start on frames other than keyframes. This
1997 improves behavior on some players when the time between keyframes is
1998 inconsistent, but may make things worse on others, and can cause some oddities
1999 during seeking. Defaults to @code{0}.
2001 @item reset_timestamps @var{1|0}
2002 Reset timestamps at the beginning of each segment, so that each segment
2003 will start with near-zero timestamps. It is meant to ease the playback
2004 of the generated segments. May not work with some combinations of
2005 muxers/codecs. It is set to @code{0} by default.
2007 @item initial_offset @var{offset}
2008 Specify timestamp offset to apply to the output packet timestamps. The
2009 argument must be a time duration specification, and defaults to 0.
2011 @item write_empty_segments @var{1|0}
2012 If enabled, write an empty segment if there are no packets during the period a
2013 segment would usually span. Otherwise, the segment will be filled with the next
2014 packet written. Defaults to @code{0}.
2017 Make sure to require a closed GOP when encoding and to set the GOP
2018 size to fit your segment time constraint.
2020 @subsection Examples
2024 Remux the content of file @file{in.mkv} to a list of segments
2025 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
2026 generated segments to @file{out.list}:
2028 ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
2032 Segment input and set output format options for the output segments:
2034 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
2038 Segment the input file according to the split points specified by the
2039 @var{segment_times} option:
2041 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
2045 Use the @command{ffmpeg} @option{force_key_frames}
2046 option to force key frames in the input at the specified location, together
2047 with the segment option @option{segment_time_delta} to account for
2048 possible roundings operated when setting key frame times.
2050 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
2051 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
2053 In order to force key frames on the input file, transcoding is
2057 Segment the input file by splitting the input file according to the
2058 frame numbers sequence specified with the @option{segment_frames} option:
2060 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
2064 Convert the @file{in.mkv} to TS segments using the @code{libx264}
2065 and @code{aac} encoders:
2067 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
2071 Segment the input file, and create an M3U8 live playlist (can be used
2072 as live HLS source):
2074 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
2075 -segment_list_flags +live -segment_time 10 out%03d.mkv
2079 @section smoothstreaming
2081 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
2085 Specify the number of fragments kept in the manifest. Default 0 (keep all).
2087 @item extra_window_size
2088 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
2090 @item lookahead_count
2091 Specify the number of lookahead fragments. Default 2.
2093 @item min_frag_duration
2094 Specify the minimum fragment duration (in microseconds). Default 5000000.
2096 @item remove_at_exit
2097 Specify whether to remove all fragments when finished. Default 0 (do not remove).
2104 Per stream hash testing format.
2106 This muxer computes and prints a cryptographic hash of all the input frames,
2107 on a per-stream basis. This can be used for equality checks without having
2108 to do a complete binary comparison.
2110 By default audio frames are converted to signed 16-bit raw audio and
2111 video frames to raw video before computing the hash, but the output
2112 of explicit conversions to other codecs can also be used. Timestamps
2113 are ignored. It uses the SHA-256 cryptographic hash function by default,
2114 but supports several other algorithms.
2116 The output of the muxer consists of one line per stream of the form:
2117 @var{streamindex},@var{streamtype},@var{algo}=@var{hash}, where
2118 @var{streamindex} is the index of the mapped stream, @var{streamtype} is a
2119 single character indicating the type of stream, @var{algo} is a short string
2120 representing the hash function used, and @var{hash} is a hexadecimal number
2121 representing the computed hash.
2124 @item hash @var{algorithm}
2125 Use the cryptographic hash function specified by the string @var{algorithm}.
2126 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
2127 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
2128 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
2129 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
2133 @subsection Examples
2135 To compute the SHA-256 hash of the input converted to raw audio and
2136 video, and store it in the file @file{out.sha256}:
2138 ffmpeg -i INPUT -f streamhash out.sha256
2141 To print an MD5 hash to stdout use the command:
2143 ffmpeg -i INPUT -f streamhash -hash md5 -
2146 See also the @ref{hash} and @ref{framehash} muxers.
2151 The fifo pseudo-muxer allows the separation of encoding and muxing by using
2152 first-in-first-out queue and running the actual muxer in a separate thread. This
2153 is especially useful in combination with the @ref{tee} muxer and can be used to
2154 send data to several destinations with different reliability/writing speed/latency.
2156 API users should be aware that callback functions (interrupt_callback,
2157 io_open and io_close) used within its AVFormatContext must be thread-safe.
2159 The behavior of the fifo muxer if the queue fills up or if the output fails is
2165 output can be transparently restarted with configurable delay between retries
2166 based on real time or time of the processed stream.
2169 encoding can be blocked during temporary failure, or continue transparently
2170 dropping packets in case fifo queue fills up.
2177 Specify the format name. Useful if it cannot be guessed from the
2181 Specify size of the queue (number of packets). Default value is 60.
2184 Specify format options for the underlying muxer. Muxer options can be specified
2185 as a list of @var{key}=@var{value} pairs separated by ':'.
2187 @item drop_pkts_on_overflow @var{bool}
2188 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
2189 rather than blocking the encoder. This makes it possible to continue streaming without
2190 delaying the input, at the cost of omitting part of the stream. By default
2191 this option is set to 0 (false), so in such cases the encoder will be blocked
2192 until the muxer processes some of the packets and none of them is lost.
2194 @item attempt_recovery @var{bool}
2195 If failure occurs, attempt to recover the output. This is especially useful
2196 when used with network output, since it makes it possible to restart streaming transparently.
2197 By default this option is set to 0 (false).
2199 @item max_recovery_attempts
2200 Sets maximum number of successive unsuccessful recovery attempts after which
2201 the output fails permanently. By default this option is set to 0 (unlimited).
2203 @item recovery_wait_time @var{duration}
2204 Waiting time before the next recovery attempt after previous unsuccessful
2205 recovery attempt. Default value is 5 seconds.
2207 @item recovery_wait_streamtime @var{bool}
2208 If set to 0 (false), the real time is used when waiting for the recovery
2209 attempt (i.e. the recovery will be attempted after at least
2210 recovery_wait_time seconds).
2211 If set to 1 (true), the time of the processed stream is taken into account
2212 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
2213 seconds of the stream is omitted).
2214 By default, this option is set to 0 (false).
2216 @item recover_any_error @var{bool}
2217 If set to 1 (true), recovery will be attempted regardless of type of the error
2218 causing the failure. By default this option is set to 0 (false) and in case of
2219 certain (usually permanent) errors the recovery is not attempted even when
2220 @var{attempt_recovery} is set to 1.
2222 @item restart_with_keyframe @var{bool}
2223 Specify whether to wait for the keyframe after recovering from
2224 queue overflow or failure. This option is set to 0 (false) by default.
2228 @subsection Examples
2233 Stream something to rtmp server, continue processing the stream at real-time
2234 rate even in case of temporary failure (network outage) and attempt to recover
2235 streaming every second indefinitely.
2237 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
2238 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
2246 The tee muxer can be used to write the same data to several outputs, such as files or streams.
2247 It can be used, for example, to stream a video over a network and save it to disk at the same time.
2249 It is different from specifying several outputs to the @command{ffmpeg}
2250 command-line tool. With the tee muxer, the audio and video data will be encoded only once.
2251 With conventional multiple outputs, multiple encoding operations in parallel are initiated,
2252 which can be a very expensive process. The tee muxer is not useful when using the libavformat API
2253 directly because it is then possible to feed the same packets to several muxers directly.
2255 Since the tee muxer does not represent any particular output format, ffmpeg cannot auto-select
2256 output streams. So all streams intended for output must be specified using @code{-map}. See
2259 Some encoders may need different options depending on the output format;
2260 the auto-detection of this can not work with the tee muxer, so they need to be explicitly specified.
2261 The main example is the @option{global_header} flag.
2263 The slave outputs are specified in the file name given to the muxer,
2264 separated by '|'. If any of the slave name contains the '|' separator,
2265 leading or trailing spaces or any special character, those must be
2266 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
2267 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
2273 @item use_fifo @var{bool}
2274 If set to 1, slave outputs will be processed in separate threads using the @ref{fifo}
2275 muxer. This allows to compensate for different speed/latency/reliability of
2276 outputs and setup transparent recovery. By default this feature is turned off.
2279 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
2283 Muxer options can be specified for each slave by prepending them as a list of
2284 @var{key}=@var{value} pairs separated by ':', between square brackets. If
2285 the options values contain a special character or the ':' separator, they
2286 must be escaped; note that this is a second level escaping.
2288 The following special options are also recognized:
2291 Specify the format name. Required if it cannot be guessed from the
2294 @item bsfs[/@var{spec}]
2295 Specify a list of bitstream filters to apply to the specified
2298 It is possible to specify to which streams a given bitstream filter
2299 applies, by appending a stream specifier to the option separated by
2300 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
2301 stream specifiers}).
2303 If the stream specifier is not specified, the bitstream filters will be
2304 applied to all streams in the output. This will cause that output operation
2305 to fail if the output contains streams to which the bitstream filter cannot
2306 be applied e.g. @code{h264_mp4toannexb} being applied to an output containing an audio stream.
2308 Options for a bitstream filter must be specified in the form of @code{opt=value}.
2310 Several bitstream filters can be specified, separated by ",".
2312 @item use_fifo @var{bool}
2313 This allows to override tee muxer use_fifo option for individual slave muxer.
2316 This allows to override tee muxer fifo_options for individual slave muxer.
2320 Select the streams that should be mapped to the slave output,
2321 specified by a stream specifier. If not specified, this defaults to
2322 all the mapped streams. This will cause that output operation to fail
2323 if the output format does not accept all mapped streams.
2325 You may use multiple stream specifiers separated by commas (@code{,}) e.g.: @code{a:0,v}
2328 Specify behaviour on output failure. This can be set to either @code{abort} (which is
2329 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
2330 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
2331 will continue without being affected.
2334 @subsection Examples
2338 Encode something and both archive it in a WebM file and stream it
2339 as MPEG-TS over UDP:
2341 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2342 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2346 As above, but continue streaming even if output to local file fails
2347 (for example local drive fills up):
2349 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2350 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2354 Use @command{ffmpeg} to encode the input, and send the output
2355 to three different destinations. The @code{dump_extra} bitstream
2356 filter is used to add extradata information to all the output video
2357 keyframes packets, as requested by the MPEG-TS format. The select
2358 option is applied to @file{out.aac} in order to make it contain only
2361 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2362 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
2366 As above, but select only stream @code{a:1} for the audio output. Note
2367 that a second level escaping must be performed, as ":" is a special
2368 character used to separate options.
2370 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2371 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
2375 @section webm_dash_manifest
2377 WebM DASH Manifest muxer.
2379 This muxer implements the WebM DASH Manifest specification to generate the DASH
2380 manifest XML. It also supports manifest generation for DASH live streams.
2382 For more information see:
2386 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
2388 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
2393 This muxer supports the following options:
2396 @item adaptation_sets
2397 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
2398 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
2399 audio and video streams. Any number of adaptation sets can be added using this option.
2402 Set this to 1 to create a live stream DASH Manifest. Default: 0.
2404 @item chunk_start_index
2405 Start index of the first chunk. This will go in the @samp{startNumber} attribute
2406 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
2408 @item chunk_duration_ms
2409 Duration of each chunk in milliseconds. This will go in the @samp{duration}
2410 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
2412 @item utc_timing_url
2413 URL of the page that will return the UTC timestamp in ISO format. This will go
2414 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
2417 @item time_shift_buffer_depth
2418 Smallest time (in seconds) shifting buffer for which any Representation is
2419 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
2420 attribute of the @samp{MPD} element. Default: 60.
2422 @item minimum_update_period
2423 Minimum update period (in seconds) of the manifest. This will go in the
2424 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
2430 ffmpeg -f webm_dash_manifest -i video1.webm \
2431 -f webm_dash_manifest -i video2.webm \
2432 -f webm_dash_manifest -i audio1.webm \
2433 -f webm_dash_manifest -i audio2.webm \
2434 -map 0 -map 1 -map 2 -map 3 \
2436 -f webm_dash_manifest \
2437 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
2443 WebM Live Chunk Muxer.
2445 This muxer writes out WebM headers and chunks as separate files which can be
2446 consumed by clients that support WebM Live streams via DASH.
2450 This muxer supports the following options:
2453 @item chunk_start_index
2454 Index of the first chunk (defaults to 0).
2457 Filename of the header where the initialization data will be written.
2459 @item audio_chunk_duration
2460 Duration of each audio chunk in milliseconds (defaults to 5000).
2465 ffmpeg -f v4l2 -i /dev/video0 \
2469 -s 640x360 -keyint_min 30 -g 30 \
2471 -header webm_live_video_360.hdr \
2472 -chunk_start_index 1 \
2473 webm_live_video_360_%d.chk \
2478 -header webm_live_audio_128.hdr \
2479 -chunk_start_index 1 \
2480 -audio_chunk_duration 1000 \
2481 webm_live_audio_128_%d.chk