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}).
93 If set to true, store positive height for raw RGB bitmaps, which indicates
94 bitmap is stored bottom-up. Note that this option does not flip the bitmap
95 which has to be done manually beforehand, e.g. by using the vflip filter.
96 Default is @var{false} and indicates bitmap is stored top down.
103 Chromaprint fingerprinter.
105 This muxer feeds audio data to the Chromaprint library,
106 which generates a fingerprint for the provided audio data. See @url{https://acoustid.org/chromaprint}
108 It takes a single signed native-endian 16-bit raw audio stream of at most 2 channels.
113 @item silence_threshold
114 Threshold for detecting silence. Range is from -1 to 32767, where -1 disables
115 silence detection. Silence detection can only be used with version 3 of the
117 Silence detection must be disabled for use with the AcoustID service. Default is -1.
120 Version of algorithm to fingerprint with. Range is 0 to 4.
121 Version 3 enables silence detection. Default is 1.
124 Format to output the fingerprint as. Accepts the following options:
127 Binary raw fingerprint
130 Binary compressed fingerprint
133 Base64 compressed fingerprint @emph{(default)}
142 CRC (Cyclic Redundancy Check) testing format.
144 This muxer computes and prints the Adler-32 CRC of all the input audio
145 and video frames. By default audio frames are converted to signed
146 16-bit raw audio and video frames to raw video before computing the
149 The output of the muxer consists of a single line of the form:
150 CRC=0x@var{CRC}, where @var{CRC} is a hexadecimal number 0-padded to
151 8 digits containing the CRC for all the decoded input frames.
153 See also the @ref{framecrc} muxer.
157 For example to compute the CRC of the input, and store it in the file
160 ffmpeg -i INPUT -f crc out.crc
163 You can print the CRC to stdout with the command:
165 ffmpeg -i INPUT -f crc -
168 You can select the output format of each frame with @command{ffmpeg} by
169 specifying the audio and video codec and format. For example to
170 compute the CRC of the input audio converted to PCM unsigned 8-bit
171 and the input video converted to MPEG-2 video, use the command:
173 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f crc -
178 Adobe Flash Video Format muxer.
180 This muxer accepts the following options:
184 @item flvflags @var{flags}
189 @item aac_seq_header_detect
190 Place AAC sequence header based on audio stream data.
192 @item no_sequence_end
193 Disable sequence end tag.
196 Disable metadata tag.
198 @item no_duration_filesize
199 Disable duration and filesize in metadata when they are equal to zero
200 at the end of stream. (Be used to non-seekable living stream).
202 @item add_keyframe_index
203 Used to facilitate seeking; particularly for HTTP pseudo streaming.
210 Dynamic Adaptive Streaming over HTTP (DASH) muxer that creates segments
211 and manifest files according to the MPEG-DASH standard ISO/IEC 23009-1:2014.
213 For more information see:
217 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
219 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
222 It creates a MPD manifest file and segment files for each stream.
224 The segment filename might contain pre-defined identifiers used with SegmentTemplate
225 as defined in section 5.3.9.4.4 of the standard. Available identifiers are "$RepresentationID$",
226 "$Number$", "$Bandwidth$" and "$Time$".
227 In addition to the standard identifiers, an ffmpeg-specific "$ext$" identifier is also supported.
228 When specified ffmpeg will replace $ext$ in the file name with muxing format's extensions such as mp4, webm etc.,
231 ffmpeg -re -i <input> -map 0 -map 0 -c:a libfdk_aac -c:v libx264 \
232 -b:v:0 800k -b:v:1 300k -s:v:1 320x170 -profile:v:1 baseline \
233 -profile:v:0 main -bf 1 -keyint_min 120 -g 120 -sc_threshold 0 \
234 -b_strategy 0 -ar:a:1 22050 -use_timeline 1 -use_template 1 \
235 -window_size 5 -adaptation_sets "id=0,streams=v id=1,streams=a" \
236 -f dash /path/to/out.mpd
240 @item min_seg_duration @var{microseconds}
241 This is a deprecated option to set the segment length in microseconds, use @var{seg_duration} instead.
242 @item seg_duration @var{duration}
243 Set the segment length in seconds (fractional value can be set). The value is
244 treated as average segment duration when @var{use_template} is enabled and
245 @item frag_duration @var{duration}
246 Set the length in seconds of fragments within segments (fractional value can be set).
247 @item frag_type @var{type}
248 Set the type of interval for fragmentation.
249 @item window_size @var{size}
250 Set the maximum number of segments kept in the manifest.
251 @item extra_window_size @var{size}
252 Set the maximum number of segments kept outside of the manifest before removing from disk.
253 @item remove_at_exit @var{remove}
254 Enable (1) or disable (0) removal of all segments when finished.
255 @item use_template @var{template}
256 Enable (1) or disable (0) use of SegmentTemplate instead of SegmentList.
257 @item use_timeline @var{timeline}
258 Enable (1) or disable (0) use of SegmentTimeline in SegmentTemplate.
259 @item single_file @var{single_file}
260 Enable (1) or disable (0) storing all segments in one file, accessed using byte ranges.
261 @item single_file_name @var{file_name}
262 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.
263 @item init_seg_name @var{init_name}
264 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.
265 @item media_seg_name @var{segment_name}
266 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.
267 @item utc_timing_url @var{utc_url}
268 URL of the page that will return the UTC timestamp in ISO format. Example: "https://time.akamai.com/?iso"
269 @item method @var{method}
270 Use the given HTTP method to create output files. Generally set to PUT or POST.
271 @item http_user_agent @var{user_agent}
272 Override User-Agent field in HTTP header. Applicable only for HTTP output.
273 @item http_persistent @var{http_persistent}
274 Use persistent HTTP connections. Applicable only for HTTP output.
275 @item hls_playlist @var{hls_playlist}
276 Generate HLS playlist files as well. The master playlist is generated with the filename @var{hls_master_name}.
277 One media playlist file is generated for each stream with filenames media_0.m3u8, media_1.m3u8, etc.
278 @item hls_master_name @var{file_name}
279 HLS master playlist name. Default is "master.m3u8".
280 @item streaming @var{streaming}
281 Enable (1) or disable (0) chunk streaming mode of output. In chunk streaming
282 mode, each frame will be a moof fragment which forms a chunk.
283 @item adaptation_sets @var{adaptation_sets}
284 Assign streams to AdaptationSets. Syntax is "id=x,streams=a,b,c id=y,streams=d,e" with x and y being the IDs
285 of the adaptation sets and a,b,c,d and e are the indices of the mapped streams.
287 To map all video (or audio) streams to an AdaptationSet, "v" (or "a") can be used as stream identifier instead of IDs.
289 When no assignment is defined, this defaults to an AdaptationSet for each stream.
291 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,
292 descriptor is useful to the scheme defined by ISO/IEC 23009-1:2014/Amd.2:2015.
293 For example, -adaptation_sets "id=0,descriptor=<SupplementalProperty schemeIdUri=\"urn:mpeg:dash:srd:2014\" value=\"0,0,0,1,1,2,2\"/>,streams=v".
294 Please note that descriptor string should be a self-closing xml tag.
295 seg_duration, frag_duration and frag_type override the global option values for each adaptation set.
296 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"
297 type_id marks an adaptation set as containing streams meant to be used for Trick Mode for the referenced adaptation set.
298 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"
299 @item timeout @var{timeout}
300 Set timeout for socket I/O operations. Applicable only for HTTP output.
301 @item index_correction @var{index_correction}
302 Enable (1) or Disable (0) segment index correction logic. Applicable only when
303 @var{use_template} is enabled and @var{use_timeline} is disabled.
305 When enabled, the logic monitors the flow of segment indexes. If a streams's
306 segment index value is not at the expected real time position, then the logic
307 corrects that index value.
309 Typically this logic is needed in live streaming use cases. The network bandwidth
310 fluctuations are common during long run streaming. Each fluctuation can cause
311 the segment indexes fall behind the expected real time position.
312 @item format_options @var{options_list}
313 Set container format (mp4/webm) options using a @code{:} separated list of
314 key=value parameters. Values containing @code{:} special characters must be
317 @item global_sidx @var{global_sidx}
318 Write global SIDX atom. Applicable only for single file, mp4 output, non-streaming mode.
320 @item dash_segment_type @var{dash_segment_type}
324 If this flag is set, the dash segment files format will be selected based on the stream codec. This is the default mode.
327 If this flag is set, the dash segment files will be in in ISOBMFF format.
330 If this flag is set, the dash segment files will be in in WebM format.
333 @item ignore_io_errors @var{ignore_io_errors}
334 Ignore IO errors during open and write. Useful for long-duration runs with network output.
336 @item lhls @var{lhls}
337 Enable Low-latency HLS(LHLS). Adds #EXT-X-PREFETCH tag with current segment's URI.
338 Apple doesn't have an official spec for LHLS. Meanwhile hls.js player folks are
339 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
340 This option will also try to comply with the above open spec, till Apple's spec officially supports it.
341 Applicable only when @var{streaming} and @var{hls_playlist} options are enabled.
342 This is an experimental feature.
344 @item ldash @var{ldash}
345 Enable Low-latency Dash by constraining the presence and values of some elements.
347 @item master_m3u8_publish_rate @var{master_m3u8_publish_rate}
348 Publish master playlist repeatedly every after specified number of segment intervals.
350 @item write_prft @var{write_prft}
351 Write Producer Reference Time elements on supported streams. This also enables writing
352 prft boxes in the underlying muxer. Applicable only when the @var{utc_url} option is enabled.
353 It's set to auto by default, in which case the muxer will attempt to enable it only in modes
356 @item mpd_profile @var{mpd_profile}
357 Set one or more manifest profiles.
359 @item http_opts @var{http_opts}
360 A :-separated list of key=value options to pass to the underlying HTTP
361 protocol. Applicable only for HTTP output.
363 @item target_latency @var{target_latency}
364 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.
365 This is an informative fields clients can use to measure the latency of the service.
367 @item min_playback_rate @var{min_playback_rate}
368 Set the minimum playback rate indicated as appropriate for the purposes of automatically
369 adjusting playback latency and buffer occupancy during normal playback by clients.
371 @item max_playback_rate @var{max_playback_rate}
372 Set the maximum playback rate indicated as appropriate for the purposes of automatically
373 adjusting playback latency and buffer occupancy during normal playback by clients.
375 @item update_period @var{update_period}
376 Set the mpd update period ,for dynamic content.
384 Per-packet CRC (Cyclic Redundancy Check) testing format.
386 This muxer computes and prints the Adler-32 CRC for each audio
387 and video packet. By default audio frames are converted to signed
388 16-bit raw audio and video frames to raw video before computing the
391 The output of the muxer consists of a line for each audio and video
394 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
397 @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
402 For example to compute the CRC of the audio and video frames in
403 @file{INPUT}, converted to raw audio and video packets, and store it
404 in the file @file{out.crc}:
406 ffmpeg -i INPUT -f framecrc out.crc
409 To print the information to stdout, use the command:
411 ffmpeg -i INPUT -f framecrc -
414 With @command{ffmpeg}, you can select the output format to which the
415 audio and video frames are encoded before computing the CRC for each
416 packet by specifying the audio and video codec. For example, to
417 compute the CRC of each decoded input audio frame converted to PCM
418 unsigned 8-bit and of each decoded input video frame converted to
419 MPEG-2 video, use the command:
421 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
424 See also the @ref{crc} muxer.
429 Per-packet hash testing format.
431 This muxer computes and prints a cryptographic hash for each audio
432 and video packet. This can be used for packet-by-packet equality
433 checks without having to individually do a binary comparison on each.
435 By default audio frames are converted to signed 16-bit raw audio and
436 video frames to raw video before computing the hash, but the output
437 of explicit conversions to other codecs can also be used. It uses the
438 SHA-256 cryptographic hash function by default, but supports several
441 The output of the muxer consists of a line for each audio and video
444 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
447 @var{hash} is a hexadecimal number representing the computed hash
451 @item hash @var{algorithm}
452 Use the cryptographic hash function specified by the string @var{algorithm}.
453 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
454 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
455 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
456 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
462 To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
463 converted to raw audio and video packets, and store it in the file
466 ffmpeg -i INPUT -f framehash out.sha256
469 To print the information to stdout, using the MD5 hash function, use
472 ffmpeg -i INPUT -f framehash -hash md5 -
475 See also the @ref{hash} muxer.
480 Per-packet MD5 testing format.
482 This is a variant of the @ref{framehash} muxer. Unlike that muxer,
483 it defaults to using the MD5 hash function.
487 To compute the MD5 hash of the audio and video frames in @file{INPUT},
488 converted to raw audio and video packets, and store it in the file
491 ffmpeg -i INPUT -f framemd5 out.md5
494 To print the information to stdout, use the command:
496 ffmpeg -i INPUT -f framemd5 -
499 See also the @ref{framehash} and @ref{md5} muxers.
506 It accepts the following options:
510 Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
511 for looping indefinitely (default).
514 Force the delay (expressed in centiseconds) after the last frame. Each frame
515 ends with a delay until the next frame. The default is @code{-1}, which is a
516 special value to tell the muxer to re-use the previous delay. In case of a
517 loop, you might want to customize this value to mark a pause for instance.
520 For example, to encode a gif looping 10 times, with a 5 seconds delay between
523 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
526 Note 1: if you wish to extract the frames into separate GIF files, you need to
527 force the @ref{image2} muxer:
529 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
532 Note 2: the GIF format has a very large time base: the delay between two frames
533 can therefore not be smaller than one centi second.
540 This muxer computes and prints a cryptographic hash of all the input
541 audio and video frames. This can be used for equality checks without
542 having to do a complete binary comparison.
544 By default audio frames are converted to signed 16-bit raw audio and
545 video frames to raw video before computing the hash, but the output
546 of explicit conversions to other codecs can also be used. Timestamps
547 are ignored. It uses the SHA-256 cryptographic hash function by default,
548 but supports several other algorithms.
550 The output of the muxer consists of a single line of the form:
551 @var{algo}=@var{hash}, where @var{algo} is a short string representing
552 the hash function used, and @var{hash} is a hexadecimal number
553 representing the computed hash.
556 @item hash @var{algorithm}
557 Use the cryptographic hash function specified by the string @var{algorithm}.
558 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
559 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
560 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
561 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
567 To compute the SHA-256 hash of the input converted to raw audio and
568 video, and store it in the file @file{out.sha256}:
570 ffmpeg -i INPUT -f hash out.sha256
573 To print an MD5 hash to stdout use the command:
575 ffmpeg -i INPUT -f hash -hash md5 -
578 See also the @ref{framehash} muxer.
583 Apple HTTP Live Streaming muxer that segments MPEG-TS according to
584 the HTTP Live Streaming (HLS) specification.
586 It creates a playlist file, and one or more segment files. The output filename
587 specifies the playlist filename.
589 By default, the muxer creates a file for each segment produced. These files
590 have the same name as the playlist, followed by a sequential number and a
593 Make sure to require a closed GOP when encoding and to set the GOP
594 size to fit your segment time constraint.
596 For example, to convert an input file with @command{ffmpeg}:
598 ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
600 This example will produce the playlist, @file{out.m3u8}, and segment files:
601 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
603 See also the @ref{segment} muxer, which provides a more generic and
604 flexible implementation of a segmenter, and can be used to perform HLS
609 This muxer supports the following options:
612 @item hls_init_time @var{duration}
613 Set the initial target segment length. Default value is @var{0}.
615 @var{duration} must be a time duration specification,
616 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
618 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
619 After the initial playlist is filled @command{ffmpeg} will cut segments
620 at duration equal to @code{hls_time}
622 @item hls_time @var{duration}
623 Set the target segment length. Default value is 2.
625 @var{duration} must be a time duration specification,
626 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
627 Segment will be cut on the next key frame after this time has passed.
629 @item hls_list_size @var{size}
630 Set the maximum number of playlist entries. If set to 0 the list file
631 will contain all the segments. Default value is 5.
633 @item hls_delete_threshold @var{size}
634 Set the number of unreferenced segments to keep on disk before @code{hls_flags delete_segments}
635 deletes them. Increase this to allow continue clients to download segments which
636 were recently referenced in the playlist. Default value is 1, meaning segments older than
637 @code{hls_list_size+1} will be deleted.
639 @item hls_ts_options @var{options_list}
640 Set output format options using a :-separated list of key=value
641 parameters. Values containing @code{:} special characters must be
644 @item hls_wrap @var{wrap}
645 This is a deprecated option, you can use @code{hls_list_size}
646 and @code{hls_flags delete_segments} instead it
648 This option is useful to avoid to fill the disk with many segment
649 files, and limits the maximum number of segment files written to disk
653 @item hls_start_number_source
654 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
655 Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
656 segment and subtitle filenames. In any case, if @code{hls_flags append_list}
657 is set and read playlist sequence number is greater than the specified start sequence number,
658 then that value will be used as start value.
660 It accepts the following values:
664 @item generic (default)
665 Set the starting sequence numbers according to @var{start_number} option value.
668 The start number will be the seconds since epoch (1970-01-01 00:00:00)
671 The start number will be the microseconds since epoch (1970-01-01 00:00:00)
674 The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
678 @item start_number @var{number}
679 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
680 when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
681 Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
684 @item hls_allow_cache @var{allowcache}
685 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
687 @item hls_base_url @var{baseurl}
688 Append @var{baseurl} to every entry in the playlist.
689 Useful to generate playlists with absolute paths.
691 Note that the playlist sequence number must be unique for each segment
692 and it is not to be confused with the segment filename sequence number
693 which can be cyclic, for example if the @option{wrap} option is
696 @item hls_segment_filename @var{filename}
697 Set the segment filename. Unless @code{hls_flags single_file} is set,
698 @var{filename} is used as a string format with the segment number:
700 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
702 This example will produce the playlist, @file{out.m3u8}, and segment files:
703 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
705 @var{filename} may contain full path or relative path specification,
706 but only the file name part without any path info will be contained in the m3u8 segment list.
707 Should a relative path be specified, the path of the created segment
708 files will be relative to the current working directory.
709 When strftime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
711 When @code{var_stream_map} is set with two or more variant streams, the
712 @var{filename} pattern must contain the string "%v", this string specifies
713 the position of variant stream index in the generated segment file names.
715 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
716 -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" \
717 -hls_segment_filename 'file_%v_%03d.ts' out_%v.m3u8
719 This example will produce the playlists segment file sets:
720 @file{file_0_000.ts}, @file{file_0_001.ts}, @file{file_0_002.ts}, etc. and
721 @file{file_1_000.ts}, @file{file_1_001.ts}, @file{file_1_002.ts}, etc.
723 The string "%v" may be present in the filename or in the last directory name
724 containing the file, but only in one of them. (Additionally, %v may appear multiple times in the last
725 sub-directory or filename.) If the string %v is present in the directory name, then
726 sub-directories are created after expanding the directory name pattern. This
727 enables creation of segments corresponding to different variant streams in
730 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
731 -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" \
732 -hls_segment_filename 'vs%v/file_%03d.ts' vs%v/out.m3u8
734 This example will produce the playlists segment file sets:
735 @file{vs0/file_000.ts}, @file{vs0/file_001.ts}, @file{vs0/file_002.ts}, etc. and
736 @file{vs1/file_000.ts}, @file{vs1/file_001.ts}, @file{vs1/file_002.ts}, etc.
739 Same as strftime option, will be deprecated.
742 Use strftime() on @var{filename} to expand the segment filename with localtime.
743 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
744 hls_flag and %%d will be the specifier.
746 ffmpeg -i in.nut -strftime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
748 This example will produce the playlist, @file{out.m3u8}, and segment files:
749 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
750 Note: On some systems/environments, the @code{%s} specifier is not available. See
751 @code{strftime()} documentation.
753 ffmpeg -i in.nut -strftime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
755 This example will produce the playlist, @file{out.m3u8}, and segment files:
756 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
758 @item use_localtime_mkdir
759 Same as strftime_mkdir option, will be deprecated .
762 Used together with -strftime_mkdir, it will create all subdirectories which
763 is expanded in @var{filename}.
765 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y%m%d/file-%Y%m%d-%s.ts' out.m3u8
767 This example will create a directory 201560215 (if it does not exist), and then
768 produce the playlist, @file{out.m3u8}, and segment files:
769 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
772 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y/%m/%d/file-%Y%m%d-%s.ts' out.m3u8
774 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
775 produce the playlist, @file{out.m3u8}, and segment files:
776 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
779 @item hls_key_info_file @var{key_info_file}
780 Use the information in @var{key_info_file} for segment encryption. The first
781 line of @var{key_info_file} specifies the key URI written to the playlist. The
782 key URL is used to access the encryption key during playback. The second line
783 specifies the path to the key file used to obtain the key during the encryption
784 process. The key file is read as a single packed array of 16 octets in binary
785 format. The optional third line specifies the initialization vector (IV) as a
786 hexadecimal string to be used instead of the segment sequence number (default)
787 for encryption. Changes to @var{key_info_file} will result in segment
788 encryption with the new key/IV and an entry in the playlist for the new key
789 URI/IV if @code{hls_flags periodic_rekey} is enabled.
791 Key info file format:
800 http://server/file.key
805 Example key file paths:
813 0123456789ABCDEF0123456789ABCDEF
816 Key info file example:
818 http://server/file.key
820 0123456789ABCDEF0123456789ABCDEF
823 Example shell script:
827 openssl rand 16 > file.key
828 echo $BASE_URL/file.key > file.keyinfo
829 echo file.key >> file.keyinfo
830 echo $(openssl rand -hex 16) >> file.keyinfo
831 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
832 -hls_key_info_file file.keyinfo out.m3u8
835 @item -hls_enc @var{enc}
836 Enable (1) or disable (0) the AES128 encryption.
837 When enabled every segment generated is encrypted and the encryption key
838 is saved as @var{playlist name}.key.
840 @item -hls_enc_key @var{key}
841 16-octet key to encrypt the segments, by default it
842 is randomly generated.
844 @item -hls_enc_key_url @var{keyurl}
845 If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
848 @item -hls_enc_iv @var{iv}
849 16-octet initialization vector for every segment instead
850 of the autogenerated ones.
852 @item hls_segment_type @var{flags}
857 Output segment files in MPEG-2 Transport Stream format. This is
858 compatible with all HLS versions.
861 Output segment files in fragmented MP4 format, similar to MPEG-DASH.
862 fmp4 files may be used in HLS version 7 and above.
866 @item hls_fmp4_init_filename @var{filename}
867 Set filename to the fragment files header file, default filename is @file{init.mp4}.
869 Use @code{-strftime 1} on @var{filename} to expand the segment filename with localtime.
871 ffmpeg -i in.nut -hls_segment_type fmp4 -strftime 1 -hls_fmp4_init_filename "%s_init.mp4" out.m3u8
873 This will produce init like this
874 @file{1602678741_init.mp4}
876 @item hls_fmp4_init_resend
877 Resend init file after m3u8 file refresh every time, default is @var{0}.
879 When @code{var_stream_map} is set with two or more variant streams, the
880 @var{filename} pattern must contain the string "%v", this string specifies
881 the position of variant stream index in the generated init file names.
882 The string "%v" may be present in the filename or in the last directory name
883 containing the file. If the string is present in the directory name, then
884 sub-directories are created after expanding the directory name pattern. This
885 enables creation of init files corresponding to different variant streams in
888 @item hls_flags @var{flags}
893 If this flag is set, the muxer will store all segments in a single MPEG-TS
894 file, and will use byte ranges in the playlist. HLS playlists generated with
895 this way will have the version number 4.
898 ffmpeg -i in.nut -hls_flags single_file out.m3u8
900 Will produce the playlist, @file{out.m3u8}, and a single segment file,
903 @item delete_segments
904 Segment files removed from the playlist are deleted after a period of time
905 equal to the duration of the segment plus the duration of the playlist.
908 Append new segments into the end of old segment list,
909 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
911 @item round_durations
912 Round the duration info in the playlist file segment info to integer
913 values, instead of using floating point.
916 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
917 first segment's information.
920 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
923 The file specified by @code{hls_key_info_file} will be checked periodically and
924 detect updates to the encryption info. Be sure to replace this file atomically,
925 including the file containing the AES encryption key.
927 @item independent_segments
928 Add the @code{#EXT-X-INDEPENDENT-SEGMENTS} to playlists that has video segments
929 and when all the segments of that playlist are guaranteed to start with a Key frame.
932 Add the @code{#EXT-X-I-FRAMES-ONLY} to playlists that has video segments
933 and can play only I-frames in the @code{#EXT-X-BYTERANGE} mode.
936 Allow segments to start on frames other than keyframes. This improves
937 behavior on some players when the time between keyframes is inconsistent,
938 but may make things worse on others, and can cause some oddities during
939 seeking. This flag should be used with the @code{hls_time} option.
941 @item program_date_time
942 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
944 @item second_level_segment_index
945 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
946 besides date/time values when strftime is on.
947 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
949 @item second_level_segment_size
950 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
951 expression besides date/time values when strftime is on.
952 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
954 @item second_level_segment_duration
955 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
956 expression besides date/time values when strftime is on.
957 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
960 ffmpeg -i sample.mpeg \
961 -f hls -hls_time 3 -hls_list_size 5 \
962 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
963 -strftime 1 -strftime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
965 This will produce segments like this:
966 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
969 Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
970 serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
971 before they have been added to the m3u8 playlist. This flag also affects how m3u8 playlist files are created.
972 If this flag is set, all playlist files will written into temporary file and renamed after they are complete, similarly as segments are handled.
973 But playlists with @code{file} protocol and with type (@code{hls_playlist_type}) other than @code{vod}
974 are always written into temporary file regardless of this flag. Master playlist files (@code{master_pl_name}), if any, with @code{file} protocol,
975 are always written into temporary file regardless of this flag if @code{master_pl_publish_rate} value is other than zero.
979 @item hls_playlist_type event
980 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
981 @option{hls_list_size} to 0; the playlist can only be appended to.
983 @item hls_playlist_type vod
984 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
985 @option{hls_list_size} to 0; the playlist must not change.
988 Use the given HTTP method to create the hls files.
990 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
992 This example will upload all the mpegts segment files to the HTTP
993 server using the HTTP PUT method, and update the m3u8 files every
994 @code{refresh} times using the same method.
995 Note that the HTTP server must support the given method for uploading
998 @item http_user_agent
999 Override User-Agent field in HTTP header. Applicable only for HTTP output.
1001 @item var_stream_map
1002 Map string which specifies how to group the audio, video and subtitle streams
1003 into different variant streams. The variant stream groups are separated
1005 Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
1006 the keys to specify audio, video and subtitle streams respectively.
1007 Allowed values are 0 to 9 (limited just based on practical usage).
1009 When there are two or more variant streams, the output filename pattern must
1010 contain the string "%v", this string specifies the position of variant stream
1011 index in the output media playlist filenames. The string "%v" may be present in
1012 the filename or in the last directory name containing the file. If the string is
1013 present in the directory name, then sub-directories are created after expanding
1014 the directory name pattern. This enables creation of variant streams in
1018 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1019 -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" \
1020 http://example.com/live/out_%v.m3u8
1022 This example creates two hls variant streams. The first variant stream will
1023 contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
1024 second variant stream will contain video stream of bitrate 256k and audio
1025 stream of bitrate 32k. Here, two media playlist with file names out_0.m3u8 and
1026 out_1.m3u8 will be created. If you want something meaningful text instead of indexes
1027 in result names, you may specify names for each or some of the variants
1028 as in the following example.
1032 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1033 -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" \
1034 http://example.com/live/out_%v.m3u8
1037 This example creates two hls variant streams as in the previous one.
1038 But here, the two media playlist with file names out_my_hd.m3u8 and
1039 out_my_sd.m3u8 will be created.
1042 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
1043 -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
1044 http://example.com/live/out_%v.m3u8
1046 This example creates three hls variant streams. The first variant stream will
1047 be a video only stream with video bitrate 1000k, the second variant stream will
1048 be an audio only stream with bitrate 64k and the third variant stream will be a
1049 video only stream with bitrate 256k. Here, three media playlist with file names
1050 out_0.m3u8, out_1.m3u8 and out_2.m3u8 will be created.
1052 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1053 -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" \
1054 http://example.com/live/vs_%v/out.m3u8
1056 This example creates the variant streams in subdirectories. Here, the first
1057 media playlist is created at @file{http://example.com/live/vs_0/out.m3u8} and
1058 the second one at @file{http://example.com/live/vs_1/out.m3u8}.
1060 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k \
1061 -map 0:a -map 0:a -map 0:v -map 0:v -f hls \
1062 -var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
1063 -master_pl_name master.m3u8 \
1064 http://example.com/live/out_%v.m3u8
1066 This example creates two audio only and two video only variant streams. In
1067 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1068 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1069 and they are mapped to the two video only variant streams with audio group names
1070 'aud_low' and 'aud_high'.
1072 By default, a single hls variant containing all the encoded streams is created.
1075 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
1076 -map 0:a -map 0:a -map 0:v -f hls \
1077 -var_stream_map "a:0,agroup:aud_low,default:yes a:1,agroup:aud_low v:0,agroup:aud_low" \
1078 -master_pl_name master.m3u8 \
1079 http://example.com/live/out_%v.m3u8
1081 This example creates two audio only and one video only variant streams. In
1082 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1083 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1084 and they are mapped to the one video only variant streams with audio group name
1085 'aud_low', and the audio group have default stat is NO or YES.
1087 By default, a single hls variant containing all the encoded streams is created.
1090 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
1091 -map 0:a -map 0:a -map 0:v -f hls \
1092 -var_stream_map "a:0,agroup:aud_low,default:yes,language:ENG a:1,agroup:aud_low,language:CHN v:0,agroup:aud_low" \
1093 -master_pl_name master.m3u8 \
1094 http://example.com/live/out_%v.m3u8
1096 This example creates two audio only and one video only variant streams. In
1097 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1098 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1099 and they are mapped to the one video only variant streams with audio group name
1100 'aud_low', and the audio group have default stat is NO or YES, and one audio
1101 have and language is named ENG, the other audio language is named CHN.
1103 By default, a single hls variant containing all the encoded streams is created.
1106 ffmpeg -y -i input_with_subtitle.mkv \
1107 -b:v:0 5250k -c:v h264 -pix_fmt yuv420p -profile:v main -level 4.1 \
1109 -c:s webvtt -c:a mp2 -ar 48000 -ac 2 -map 0:v -map 0:a:0 -map 0:s:0 \
1110 -f hls -var_stream_map "v:0,a:0,s:0,sgroup:subtitle" \
1111 -master_pl_name master.m3u8 -t 300 -hls_time 10 -hls_init_time 4 -hls_list_size \
1112 10 -master_pl_publish_rate 10 -hls_flags \
1113 delete_segments+discont_start+split_by_time ./tmp/video.m3u8
1116 This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=SUBTITLES} in
1117 the master playlist with webvtt subtitle group name 'subtitle'. Please make sure
1118 the input file has one text subtitle stream at least.
1121 Map string which specifies different closed captions groups and their
1122 attributes. The closed captions stream groups are separated by space.
1123 Expected string format is like this
1124 "ccgroup:<group name>,instreamid:<INSTREAM-ID>,language:<language code> ....".
1125 'ccgroup' and 'instreamid' are mandatory attributes. 'language' is an optional
1127 The closed captions groups configured using this option are mapped to different
1128 variant streams by providing the same 'ccgroup' name in the
1129 @code{var_stream_map} string. If @code{var_stream_map} is not set, then the
1130 first available ccgroup in @code{cc_stream_map} is mapped to the output variant
1131 stream. The examples for these two use cases are given below.
1134 ffmpeg -re -i in.ts -b:v 1000k -b:a 64k -a53cc 1 -f hls \
1135 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en" \
1136 -master_pl_name master.m3u8 \
1137 http://example.com/live/out.m3u8
1139 This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=CLOSED-CAPTIONS} in
1140 the master playlist with group name 'cc', language 'en' (english) and
1141 INSTREAM-ID 'CC1'. Also, it adds @code{CLOSED-CAPTIONS} attribute with group
1142 name 'cc' for the output variant stream.
1144 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1145 -a53cc:0 1 -a53cc:1 1\
1146 -map 0:v -map 0:a -map 0:v -map 0:a -f hls \
1147 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en ccgroup:cc,instreamid:CC2,language:sp" \
1148 -var_stream_map "v:0,a:0,ccgroup:cc v:1,a:1,ccgroup:cc" \
1149 -master_pl_name master.m3u8 \
1150 http://example.com/live/out_%v.m3u8
1152 This example adds two @code{#EXT-X-MEDIA} tags with @code{TYPE=CLOSED-CAPTIONS} in
1153 the master playlist for the INSTREAM-IDs 'CC1' and 'CC2'. Also, it adds
1154 @code{CLOSED-CAPTIONS} attribute with group name 'cc' for the two output variant
1157 @item master_pl_name
1158 Create HLS master playlist with the given name.
1161 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
1163 This example creates HLS master playlist with name master.m3u8 and it is
1164 published at http://example.com/live/
1166 @item master_pl_publish_rate
1167 Publish master play list repeatedly every after specified number of segment intervals.
1170 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
1171 -hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
1174 This example creates HLS master playlist with name master.m3u8 and keep
1175 publishing it repeatedly every after 30 segments i.e. every after 60s.
1177 @item http_persistent
1178 Use persistent HTTP connections. Applicable only for HTTP output.
1181 Set timeout for socket I/O operations. Applicable only for HTTP output.
1183 @item -ignore_io_errors
1184 Ignore IO errors during open, write and delete. Useful for long-duration runs with network output.
1187 Set custom HTTP headers, can override built in default headers. Applicable only for HTTP output.
1196 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
1200 Size cannot exceed 256 pixels in any dimension
1203 Only BMP and PNG images can be stored
1206 If a BMP image is used, it must be one of the following pixel formats:
1208 BMP Bit Depth FFmpeg Pixel Format
1218 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
1221 If a PNG image is used, it must use the rgba pixel format
1229 The image file muxer writes video frames to image files.
1231 The output filenames are specified by a pattern, which can be used to
1232 produce sequentially numbered series of files.
1233 The pattern may contain the string "%d" or "%0@var{N}d", this string
1234 specifies the position of the characters representing a numbering in
1235 the filenames. If the form "%0@var{N}d" is used, the string
1236 representing the number in each filename is 0-padded to @var{N}
1237 digits. The literal character '%' can be specified in the pattern with
1240 If the pattern contains "%d" or "%0@var{N}d", the first filename of
1241 the file list specified will contain the number 1, all the following
1242 numbers will be sequential.
1244 The pattern may contain a suffix which is used to automatically
1245 determine the format of the image files to write.
1247 For example the pattern "img-%03d.bmp" will specify a sequence of
1248 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
1249 @file{img-010.bmp}, etc.
1250 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
1251 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
1254 The image muxer supports the .Y.U.V image file format. This format is
1255 special in that that each image frame consists of three files, for
1256 each of the YUV420P components. To read or write this image file format,
1257 specify the name of the '.Y' file. The muxer will automatically open the
1258 '.U' and '.V' files as required.
1264 If set to 1, expand the filename with pts from pkt->pts.
1268 Start the sequence from the specified number. Default value is 1.
1271 If set to 1, the filename will always be interpreted as just a
1272 filename, not a pattern, and the corresponding file will be continuously
1273 overwritten with new images. Default value is 0.
1276 If set to 1, expand the filename with date and time information from
1277 @code{strftime()}. Default value is 0.
1279 @item protocol_opts @var{options_list}
1280 Set protocol options as a :-separated list of key=value parameters. Values
1281 containing the @code{:} special character must be escaped.
1285 @subsection Examples
1287 The following example shows how to use @command{ffmpeg} for creating a
1288 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
1289 taking one image every second from the input video:
1291 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
1294 Note that with @command{ffmpeg}, if the format is not specified with the
1295 @code{-f} option and the output filename specifies an image file
1296 format, the image2 muxer is automatically selected, so the previous
1297 command can be written as:
1299 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
1302 Note also that the pattern must not necessarily contain "%d" or
1303 "%0@var{N}d", for example to create a single image file
1304 @file{img.jpeg} from the start of the input video you can employ the command:
1306 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
1309 The @option{strftime} option allows you to expand the filename with
1310 date and time information. Check the documentation of
1311 the @code{strftime()} function for the syntax.
1313 For example to generate image files from the @code{strftime()}
1314 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
1317 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
1320 You can set the file name with current frame's PTS:
1322 ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
1325 A more complex example is to publish contents of your desktop directly to a
1326 WebDAV server every second:
1328 ffmpeg -f x11grab -framerate 1 -i :0.0 -q:v 6 -update 1 -protocol_opts method=PUT http://example.com/desktop.jpg
1333 Matroska container muxer.
1335 This muxer implements the matroska and webm container specs.
1337 @subsection Metadata
1339 The recognized metadata settings in this muxer are:
1343 Set title name provided to a single track. This gets mapped to
1344 the FileDescription element for a stream written as attachment.
1347 Specify the language of the track in the Matroska languages form.
1349 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
1350 639-2/B) form (like "fre" for French), or a language code mixed with a
1351 country code for specialities in languages (like "fre-ca" for Canadian
1355 Set stereo 3D video layout of two views in a single video track.
1357 The following values are recognized:
1362 Both views are arranged side by side, Left-eye view is on the left
1364 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
1366 Both views are arranged in top-bottom orientation, Left-eye view is on top
1367 @item checkerboard_rl
1368 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
1369 @item checkerboard_lr
1370 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
1371 @item row_interleaved_rl
1372 Each view is constituted by a row based interleaving, Right-eye view is first row
1373 @item row_interleaved_lr
1374 Each view is constituted by a row based interleaving, Left-eye view is first row
1375 @item col_interleaved_rl
1376 Both views are arranged in a column based interleaving manner, Right-eye view is first column
1377 @item col_interleaved_lr
1378 Both views are arranged in a column based interleaving manner, Left-eye view is first column
1379 @item anaglyph_cyan_red
1380 All frames are in anaglyph format viewable through red-cyan filters
1382 Both views are arranged side by side, Right-eye view is on the left
1383 @item anaglyph_green_magenta
1384 All frames are in anaglyph format viewable through green-magenta filters
1386 Both eyes laced in one Block, Left-eye view is first
1388 Both eyes laced in one Block, Right-eye view is first
1392 For example a 3D WebM clip can be created using the following command line:
1394 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
1399 This muxer supports the following options:
1402 @item reserve_index_space
1403 By default, this muxer writes the index for seeking (called cues in Matroska
1404 terms) at the end of the file, because it cannot know in advance how much space
1405 to leave for the index at the beginning of the file. However for some use cases
1406 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
1407 index at the beginning of the file.
1409 If this option is set to a non-zero value, the muxer will reserve a given amount
1410 of space in the file header and then try to write the cues there when the muxing
1411 finishes. If the reserved space does not suffice, no Cues will be written, the
1412 file will be finalized and writing the trailer will return an error.
1413 A safe size for most use cases should be about 50kB per hour of video.
1415 Note that cues are only written if the output is seekable and this option will
1416 have no effect if it is not.
1418 This option controls how the FlagDefault of the output tracks will be set.
1419 It influences which tracks players should play by default. The default mode
1423 In this mode, for each type of track (audio, video or subtitle), if there is
1424 a track with disposition default of this type, then the first such track
1425 (i.e. the one with the lowest index) will be marked as default; if no such
1426 track exists, the first track of this type will be marked as default instead
1427 (if existing). This ensures that the default flag is set in a sensible way even
1428 if the input originated from containers that lack the concept of default tracks.
1430 This mode is the same as infer except that if no subtitle track with
1431 disposition default exists, no subtitle track will be marked as default.
1433 In this mode the FlagDefault is set if and only if the AV_DISPOSITION_DEFAULT
1434 flag is set in the disposition of the corresponding stream.
1437 @item flipped_raw_rgb
1438 If set to true, store positive height for raw RGB bitmaps, which indicates
1439 bitmap is stored bottom-up. Note that this option does not flip the bitmap
1440 which has to be done manually beforehand, e.g. by using the vflip filter.
1441 Default is @var{false} and indicates bitmap is stored top down.
1450 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
1451 defaults to using the MD5 hash function.
1453 @subsection Examples
1455 To compute the MD5 hash of the input converted to raw
1456 audio and video, and store it in the file @file{out.md5}:
1458 ffmpeg -i INPUT -f md5 out.md5
1461 You can print the MD5 to stdout with the command:
1463 ffmpeg -i INPUT -f md5 -
1466 See also the @ref{hash} and @ref{framemd5} muxers.
1468 @section mov, mp4, ismv
1470 MOV/MP4/ISMV (Smooth Streaming) muxer.
1472 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
1473 file has all the metadata about all packets stored in one location
1474 (written at the end of the file, it can be moved to the start for
1475 better playback by adding @var{faststart} to the @var{movflags}, or
1476 using the @command{qt-faststart} tool). A fragmented
1477 file consists of a number of fragments, where packets and metadata
1478 about these packets are stored together. Writing a fragmented
1479 file has the advantage that the file is decodable even if the
1480 writing is interrupted (while a normal MOV/MP4 is undecodable if
1481 it is not properly finished), and it requires less memory when writing
1482 very long files (since writing normal MOV/MP4 files stores info about
1483 every single packet in memory until the file is closed). The downside
1484 is that it is less compatible with other applications.
1488 Fragmentation is enabled by setting one of the AVOptions that define
1489 how to cut the file into fragments:
1492 @item -moov_size @var{bytes}
1493 Reserves space for the moov atom at the beginning of the file instead of placing the
1494 moov atom at the end. If the space reserved is insufficient, muxing will fail.
1495 @item -movflags frag_keyframe
1496 Start a new fragment at each video keyframe.
1497 @item -frag_duration @var{duration}
1498 Create fragments that are @var{duration} microseconds long.
1499 @item -frag_size @var{size}
1500 Create fragments that contain up to @var{size} bytes of payload data.
1501 @item -movflags frag_custom
1502 Allow the caller to manually choose when to cut fragments, by
1503 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
1504 the packets written so far. (This is only useful with other
1505 applications integrating libavformat, not from @command{ffmpeg}.)
1506 @item -min_frag_duration @var{duration}
1507 Don't create fragments that are shorter than @var{duration} microseconds long.
1510 If more than one condition is specified, fragments are cut when
1511 one of the specified conditions is fulfilled. The exception to this is
1512 @code{-min_frag_duration}, which has to be fulfilled for any of the other
1513 conditions to apply.
1515 Additionally, the way the output file is written can be adjusted
1516 through a few other options:
1519 @item -movflags empty_moov
1520 Write an initial moov atom directly at the start of the file, without
1521 describing any samples in it. Generally, an mdat/moov pair is written
1522 at the start of the file, as a normal MOV/MP4 file, containing only
1523 a short portion of the file. With this option set, there is no initial
1524 mdat atom, and the moov atom only describes the tracks but has
1527 This option is implicitly set when writing ismv (Smooth Streaming) files.
1528 @item -movflags separate_moof
1529 Write a separate moof (movie fragment) atom for each track. Normally,
1530 packets for all tracks are written in a moof atom (which is slightly
1531 more efficient), but with this option set, the muxer writes one moof/mdat
1532 pair for each track, making it easier to separate tracks.
1534 This option is implicitly set when writing ismv (Smooth Streaming) files.
1535 @item -movflags skip_sidx
1536 Skip writing of sidx atom. When bitrate overhead due to sidx atom is high,
1537 this option could be used for cases where sidx atom is not mandatory.
1538 When global_sidx flag is enabled, this option will be ignored.
1539 @item -movflags faststart
1540 Run a second pass moving the index (moov atom) to the beginning of the file.
1541 This operation can take a while, and will not work in various situations such
1542 as fragmented output, thus it is not enabled by default.
1543 @item -movflags rtphint
1544 Add RTP hinting tracks to the output file.
1545 @item -movflags disable_chpl
1546 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
1547 and a QuickTime chapter track are written to the file. With this option
1548 set, only the QuickTime chapter track will be written. Nero chapters can
1549 cause failures when the file is reprocessed with certain tagging programs, like
1550 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
1551 @item -movflags omit_tfhd_offset
1552 Do not write any absolute base_data_offset in tfhd atoms. This avoids
1553 tying fragments to absolute byte positions in the file/streams.
1554 @item -movflags default_base_moof
1555 Similarly to the omit_tfhd_offset, this flag avoids writing the
1556 absolute base_data_offset field in tfhd atoms, but does so by using
1557 the new default-base-is-moof flag instead. This flag is new from
1558 14496-12:2012. This may make the fragments easier to parse in certain
1559 circumstances (avoiding basing track fragment location calculations
1560 on the implicit end of the previous track fragment).
1562 Specify @code{on} to force writing a timecode track, @code{off} to disable it
1563 and @code{auto} to write a timecode track only for mov and mp4 output (default).
1564 @item -movflags negative_cts_offsets
1565 Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
1566 be negative. This enables the initial sample to have DTS/CTS of zero, and
1567 reduces the need for edit lists for some cases such as video tracks with
1568 B-frames. Additionally, eases conformance with the DASH-IF interoperability
1571 This option is implicitly set when writing ismv (Smooth Streaming) files.
1573 Write producer time reference box (PRFT) with a specified time source for the
1574 NTP field in the PRFT box. Set value as @samp{wallclock} to specify timesource
1575 as wallclock time and @samp{pts} to specify timesource as input packets' PTS
1578 Setting value to @samp{pts} is applicable only for a live encoding use case,
1579 where PTS values are set as as wallclock time at the source. For example, an
1580 encoding use case with decklink capture source where @option{video_pts} and
1581 @option{audio_pts} are set to @samp{abs_wallclock}.
1586 Smooth Streaming content can be pushed in real time to a publishing
1587 point on IIS with this muxer. Example:
1589 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
1594 The MP3 muxer writes a raw MP3 stream with the following optional features:
1597 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
1598 2.4 are supported, the @code{id3v2_version} private option controls which one is
1599 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
1602 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
1603 The pictures are supplied to the muxer in form of a video stream with a single
1604 packet. There can be any number of those streams, each will correspond to a
1605 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
1606 to APIC @var{description} and @var{picture type} respectively. See
1607 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
1609 Note that the APIC frames must be written at the beginning, so the muxer will
1610 buffer the audio frames until it gets all the pictures. It is therefore advised
1611 to provide the pictures as soon as possible to avoid excessive buffering.
1614 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
1615 default, but will be written only if the output is seekable. The
1616 @code{write_xing} private option can be used to disable it. The frame contains
1617 various information that may be useful to the decoder, like the audio duration
1621 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1622 enabled with the @code{write_id3v1} private option, but as its capabilities are
1623 very limited, its usage is not recommended.
1628 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1630 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1633 To attach a picture to an mp3 file select both the audio and the picture stream
1636 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1637 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1640 Write a "clean" MP3 without any extra features:
1642 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1647 MPEG transport stream muxer.
1649 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1651 The recognized metadata settings in mpegts muxer are @code{service_provider}
1652 and @code{service_name}. If they are not set the default for
1653 @code{service_provider} is @samp{FFmpeg} and the default for
1654 @code{service_name} is @samp{Service01}.
1658 The muxer options are:
1661 @item mpegts_transport_stream_id @var{integer}
1662 Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
1663 Default is @code{0x0001}.
1665 @item mpegts_original_network_id @var{integer}
1666 Set the @samp{original_network_id}. This is unique identifier of a
1667 network in DVB. Its main use is in the unique identification of a service
1668 through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
1671 @item mpegts_service_id @var{integer}
1672 Set the @samp{service_id}, also known as program in DVB. Default is
1675 @item mpegts_service_type @var{integer}
1676 Set the program @samp{service_type}. Default is @code{digital_tv}.
1677 Accepts the following options:
1680 Any hexadecimal value between @code{0x01} and @code{0xff} as defined in
1685 Digital Radio service.
1688 @item advanced_codec_digital_radio
1689 Advanced Codec Digital Radio service.
1690 @item mpeg2_digital_hdtv
1691 MPEG2 Digital HDTV service.
1692 @item advanced_codec_digital_sdtv
1693 Advanced Codec Digital SDTV service.
1694 @item advanced_codec_digital_hdtv
1695 Advanced Codec Digital HDTV service.
1698 @item mpegts_pmt_start_pid @var{integer}
1699 Set the first PID for PMTs. Default is @code{0x1000}, minimum is @code{0x0020},
1700 maximum is @code{0x1ffa}. This option has no effect in m2ts mode where the PMT
1701 PID is fixed @code{0x0100}.
1703 @item mpegts_start_pid @var{integer}
1704 Set the first PID for elementary streams. Default is @code{0x0100}, minimum is
1705 @code{0x0020}, maximum is @code{0x1ffa}. This option has no effect in m2ts mode
1706 where the elementary stream PIDs are fixed.
1708 @item mpegts_m2ts_mode @var{boolean}
1709 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
1712 @item muxrate @var{integer}
1713 Set a constant muxrate. Default is VBR.
1715 @item pes_payload_size @var{integer}
1716 Set minimum PES packet payload in bytes. Default is @code{2930}.
1718 @item mpegts_flags @var{flags}
1719 Set mpegts flags. Accepts the following options:
1721 @item resend_headers
1722 Reemit PAT/PMT before writing the next packet.
1724 Use LATM packetization for AAC.
1725 @item pat_pmt_at_frames
1726 Reemit PAT and PMT at each video frame.
1728 Conform to System B (DVB) instead of System A (ATSC).
1729 @item initial_discontinuity
1730 Mark the initial packet of each stream as discontinuity.
1733 @item mpegts_copyts @var{boolean}
1734 Preserve original timestamps, if value is set to @code{1}. Default value
1735 is @code{-1}, which results in shifting timestamps so that they start from 0.
1737 @item omit_video_pes_length @var{boolean}
1738 Omit the PES packet length for video packets. Default is @code{1} (true).
1740 @item pcr_period @var{integer}
1741 Override the default PCR retransmission time in milliseconds. Default is
1742 @code{-1} which means that the PCR interval will be determined automatically:
1743 20 ms is used for CBR streams, the highest multiple of the frame duration which
1744 is less than 100 ms is used for VBR streams.
1746 @item pat_period @var{duration}
1747 Maximum time in seconds between PAT/PMT tables. Default is @code{0.1}.
1749 @item sdt_period @var{duration}
1750 Maximum time in seconds between SDT tables. Default is @code{0.5}.
1752 @item tables_version @var{integer}
1753 Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
1754 This option allows updating stream structure so that standard consumer may
1755 detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
1756 usage) or restart @command{ffmpeg} instance, cyclically changing
1757 @option{tables_version} value:
1760 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1761 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1763 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1764 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1765 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1773 ffmpeg -i file.mpg -c copy \
1774 -mpegts_original_network_id 0x1122 \
1775 -mpegts_transport_stream_id 0x3344 \
1776 -mpegts_service_id 0x5566 \
1777 -mpegts_pmt_start_pid 0x1500 \
1778 -mpegts_start_pid 0x150 \
1779 -metadata service_provider="Some provider" \
1780 -metadata service_name="Some Channel" \
1784 @section mxf, mxf_d10, mxf_opatom
1790 The muxer options are:
1793 @item store_user_comments @var{bool}
1794 Set if user comments should be stored if available or never.
1795 IRT D-10 does not allow user comments. The default is thus to write them for
1796 mxf and mxf_opatom but not for mxf_d10
1803 This muxer does not generate any output file, it is mainly useful for
1804 testing or benchmarking purposes.
1806 For example to benchmark decoding with @command{ffmpeg} you can use the
1809 ffmpeg -benchmark -i INPUT -f null out.null
1812 Note that the above command does not read or write the @file{out.null}
1813 file, but specifying the output file is required by the @command{ffmpeg}
1816 Alternatively you can write the command as:
1818 ffmpeg -benchmark -i INPUT -f null -
1824 @item -syncpoints @var{flags}
1825 Change the syncpoint usage in nut:
1827 @item @var{default} use the normal low-overhead seeking aids.
1828 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1829 Use of this option is not recommended, as the resulting files are very damage
1830 sensitive and seeking is not possible. Also in general the overhead from
1831 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1832 all growing data tables, allowing to mux endless streams with limited memory
1833 and without these disadvantages.
1834 @item @var{timestamped} extend the syncpoint with a wallclock field.
1836 The @var{none} and @var{timestamped} flags are experimental.
1837 @item -write_index @var{bool}
1838 Write index at the end, the default is to write an index.
1842 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1847 Ogg container muxer.
1850 @item -page_duration @var{duration}
1851 Preferred page duration, in microseconds. The muxer will attempt to create
1852 pages that are approximately @var{duration} microseconds long. This allows the
1853 user to compromise between seek granularity and container overhead. The default
1854 is 1 second. A value of 0 will fill all segments, making pages as large as
1855 possible. A value of 1 will effectively use 1 packet-per-page in most
1856 situations, giving a small seek granularity at the cost of additional container
1858 @item -serial_offset @var{value}
1859 Serial value from which to set the streams serial number.
1860 Setting it to different and sufficiently large values ensures that the produced
1861 ogg files can be safely chained.
1866 @section segment, stream_segment, ssegment
1868 Basic stream segmenter.
1870 This muxer outputs streams to a number of separate files of nearly
1871 fixed duration. Output filename pattern can be set in a fashion
1872 similar to @ref{image2}, or by using a @code{strftime} template if
1873 the @option{strftime} option is enabled.
1875 @code{stream_segment} is a variant of the muxer used to write to
1876 streaming output formats, i.e. which do not require global headers,
1877 and is recommended for outputting e.g. to MPEG transport stream segments.
1878 @code{ssegment} is a shorter alias for @code{stream_segment}.
1880 Every segment starts with a keyframe of the selected reference stream,
1881 which is set through the @option{reference_stream} option.
1883 Note that if you want accurate splitting for a video file, you need to
1884 make the input key frames correspond to the exact splitting times
1885 expected by the segmenter, or the segment muxer will start the new
1886 segment with the key frame found next after the specified start
1889 The segment muxer works best with a single constant frame rate video.
1891 Optionally it can generate a list of the created segments, by setting
1892 the option @var{segment_list}. The list type is specified by the
1893 @var{segment_list_type} option. The entry filenames in the segment
1894 list are set by default to the basename of the corresponding segment
1897 See also the @ref{hls} muxer, which provides a more specific
1898 implementation for HLS segmentation.
1902 The segment muxer supports the following options:
1905 @item increment_tc @var{1|0}
1906 if set to @code{1}, increment timecode between each segment
1907 If this is selected, the input need to have
1908 a timecode in the first video stream. Default value is
1911 @item reference_stream @var{specifier}
1912 Set the reference stream, as specified by the string @var{specifier}.
1913 If @var{specifier} is set to @code{auto}, the reference is chosen
1914 automatically. Otherwise it must be a stream specifier (see the ``Stream
1915 specifiers'' chapter in the ffmpeg manual) which specifies the
1916 reference stream. The default value is @code{auto}.
1918 @item segment_format @var{format}
1919 Override the inner container format, by default it is guessed by the filename
1922 @item segment_format_options @var{options_list}
1923 Set output format options using a :-separated list of key=value
1924 parameters. Values containing the @code{:} special character must be
1927 @item segment_list @var{name}
1928 Generate also a listfile named @var{name}. If not specified no
1929 listfile is generated.
1931 @item segment_list_flags @var{flags}
1932 Set flags affecting the segment list generation.
1934 It currently supports the following flags:
1937 Allow caching (only affects M3U8 list files).
1940 Allow live-friendly file generation.
1943 @item segment_list_size @var{size}
1944 Update the list file so that it contains at most @var{size}
1945 segments. If 0 the list file will contain all the segments. Default
1948 @item segment_list_entry_prefix @var{prefix}
1949 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1950 By default no prefix is applied.
1952 @item segment_list_type @var{type}
1953 Select the listing format.
1955 The following values are recognized:
1958 Generate a flat list for the created segments, one segment per line.
1961 Generate a list for the created segments, one segment per line,
1962 each line matching the format (comma-separated values):
1964 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1967 @var{segment_filename} is the name of the output file generated by the
1968 muxer according to the provided pattern. CSV escaping (according to
1969 RFC4180) is applied if required.
1971 @var{segment_start_time} and @var{segment_end_time} specify
1972 the segment start and end time expressed in seconds.
1974 A list file with the suffix @code{".csv"} or @code{".ext"} will
1975 auto-select this format.
1977 @samp{ext} is deprecated in favor or @samp{csv}.
1980 Generate an ffconcat file for the created segments. The resulting file
1981 can be read using the FFmpeg @ref{concat} demuxer.
1983 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1984 auto-select this format.
1987 Generate an extended M3U8 file, version 3, compliant with
1988 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1990 A list file with the suffix @code{".m3u8"} will auto-select this format.
1993 If not specified the type is guessed from the list file name suffix.
1995 @item segment_time @var{time}
1996 Set segment duration to @var{time}, the value must be a duration
1997 specification. Default value is "2". See also the
1998 @option{segment_times} option.
2000 Note that splitting may not be accurate, unless you force the
2001 reference stream key-frames at the given time. See the introductory
2002 notice and the examples below.
2004 @item segment_atclocktime @var{1|0}
2005 If set to "1" split at regular clock time intervals starting from 00:00
2006 o'clock. The @var{time} value specified in @option{segment_time} is
2007 used for setting the length of the splitting interval.
2009 For example with @option{segment_time} set to "900" this makes it possible
2010 to create files at 12:00 o'clock, 12:15, 12:30, etc.
2012 Default value is "0".
2014 @item segment_clocktime_offset @var{duration}
2015 Delay the segment splitting times with the specified duration when using
2016 @option{segment_atclocktime}.
2018 For example with @option{segment_time} set to "900" and
2019 @option{segment_clocktime_offset} set to "300" this makes it possible to
2020 create files at 12:05, 12:20, 12:35, etc.
2022 Default value is "0".
2024 @item segment_clocktime_wrap_duration @var{duration}
2025 Force the segmenter to only start a new segment if a packet reaches the muxer
2026 within the specified duration after the segmenting clock time. This way you
2027 can make the segmenter more resilient to backward local time jumps, such as
2028 leap seconds or transition to standard time from daylight savings time.
2030 Default is the maximum possible duration which means starting a new segment
2031 regardless of the elapsed time since the last clock time.
2033 @item segment_time_delta @var{delta}
2034 Specify the accuracy time when selecting the start time for a
2035 segment, expressed as a duration specification. Default value is "0".
2037 When delta is specified a key-frame will start a new segment if its
2038 PTS satisfies the relation:
2040 PTS >= start_time - time_delta
2043 This option is useful when splitting video content, which is always
2044 split at GOP boundaries, in case a key frame is found just before the
2045 specified split time.
2047 In particular may be used in combination with the @file{ffmpeg} option
2048 @var{force_key_frames}. The key frame times specified by
2049 @var{force_key_frames} may not be set accurately because of rounding
2050 issues, with the consequence that a key frame time may result set just
2051 before the specified time. For constant frame rate videos a value of
2052 1/(2*@var{frame_rate}) should address the worst case mismatch between
2053 the specified time and the time set by @var{force_key_frames}.
2055 @item segment_times @var{times}
2056 Specify a list of split points. @var{times} contains a list of comma
2057 separated duration specifications, in increasing order. See also
2058 the @option{segment_time} option.
2060 @item segment_frames @var{frames}
2061 Specify a list of split video frame numbers. @var{frames} contains a
2062 list of comma separated integer numbers, in increasing order.
2064 This option specifies to start a new segment whenever a reference
2065 stream key frame is found and the sequential number (starting from 0)
2066 of the frame is greater or equal to the next value in the list.
2068 @item segment_wrap @var{limit}
2069 Wrap around segment index once it reaches @var{limit}.
2071 @item segment_start_number @var{number}
2072 Set the sequence number of the first segment. Defaults to @code{0}.
2074 @item strftime @var{1|0}
2075 Use the @code{strftime} function to define the name of the new
2076 segments to write. If this is selected, the output segment name must
2077 contain a @code{strftime} function template. Default value is
2080 @item break_non_keyframes @var{1|0}
2081 If enabled, allow segments to start on frames other than keyframes. This
2082 improves behavior on some players when the time between keyframes is
2083 inconsistent, but may make things worse on others, and can cause some oddities
2084 during seeking. Defaults to @code{0}.
2086 @item reset_timestamps @var{1|0}
2087 Reset timestamps at the beginning of each segment, so that each segment
2088 will start with near-zero timestamps. It is meant to ease the playback
2089 of the generated segments. May not work with some combinations of
2090 muxers/codecs. It is set to @code{0} by default.
2092 @item initial_offset @var{offset}
2093 Specify timestamp offset to apply to the output packet timestamps. The
2094 argument must be a time duration specification, and defaults to 0.
2096 @item write_empty_segments @var{1|0}
2097 If enabled, write an empty segment if there are no packets during the period a
2098 segment would usually span. Otherwise, the segment will be filled with the next
2099 packet written. Defaults to @code{0}.
2102 Make sure to require a closed GOP when encoding and to set the GOP
2103 size to fit your segment time constraint.
2105 @subsection Examples
2109 Remux the content of file @file{in.mkv} to a list of segments
2110 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
2111 generated segments to @file{out.list}:
2113 ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
2117 Segment input and set output format options for the output segments:
2119 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
2123 Segment the input file according to the split points specified by the
2124 @var{segment_times} option:
2126 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
2130 Use the @command{ffmpeg} @option{force_key_frames}
2131 option to force key frames in the input at the specified location, together
2132 with the segment option @option{segment_time_delta} to account for
2133 possible roundings operated when setting key frame times.
2135 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
2136 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
2138 In order to force key frames on the input file, transcoding is
2142 Segment the input file by splitting the input file according to the
2143 frame numbers sequence specified with the @option{segment_frames} option:
2145 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
2149 Convert the @file{in.mkv} to TS segments using the @code{libx264}
2150 and @code{aac} encoders:
2152 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
2156 Segment the input file, and create an M3U8 live playlist (can be used
2157 as live HLS source):
2159 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
2160 -segment_list_flags +live -segment_time 10 out%03d.mkv
2164 @section smoothstreaming
2166 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
2170 Specify the number of fragments kept in the manifest. Default 0 (keep all).
2172 @item extra_window_size
2173 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
2175 @item lookahead_count
2176 Specify the number of lookahead fragments. Default 2.
2178 @item min_frag_duration
2179 Specify the minimum fragment duration (in microseconds). Default 5000000.
2181 @item remove_at_exit
2182 Specify whether to remove all fragments when finished. Default 0 (do not remove).
2189 Per stream hash testing format.
2191 This muxer computes and prints a cryptographic hash of all the input frames,
2192 on a per-stream basis. This can be used for equality checks without having
2193 to do a complete binary comparison.
2195 By default audio frames are converted to signed 16-bit raw audio and
2196 video frames to raw video before computing the hash, but the output
2197 of explicit conversions to other codecs can also be used. Timestamps
2198 are ignored. It uses the SHA-256 cryptographic hash function by default,
2199 but supports several other algorithms.
2201 The output of the muxer consists of one line per stream of the form:
2202 @var{streamindex},@var{streamtype},@var{algo}=@var{hash}, where
2203 @var{streamindex} is the index of the mapped stream, @var{streamtype} is a
2204 single character indicating the type of stream, @var{algo} is a short string
2205 representing the hash function used, and @var{hash} is a hexadecimal number
2206 representing the computed hash.
2209 @item hash @var{algorithm}
2210 Use the cryptographic hash function specified by the string @var{algorithm}.
2211 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
2212 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
2213 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
2214 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
2218 @subsection Examples
2220 To compute the SHA-256 hash of the input converted to raw audio and
2221 video, and store it in the file @file{out.sha256}:
2223 ffmpeg -i INPUT -f streamhash out.sha256
2226 To print an MD5 hash to stdout use the command:
2228 ffmpeg -i INPUT -f streamhash -hash md5 -
2231 See also the @ref{hash} and @ref{framehash} muxers.
2236 The fifo pseudo-muxer allows the separation of encoding and muxing by using
2237 first-in-first-out queue and running the actual muxer in a separate thread. This
2238 is especially useful in combination with the @ref{tee} muxer and can be used to
2239 send data to several destinations with different reliability/writing speed/latency.
2241 API users should be aware that callback functions (interrupt_callback,
2242 io_open and io_close) used within its AVFormatContext must be thread-safe.
2244 The behavior of the fifo muxer if the queue fills up or if the output fails is
2250 output can be transparently restarted with configurable delay between retries
2251 based on real time or time of the processed stream.
2254 encoding can be blocked during temporary failure, or continue transparently
2255 dropping packets in case fifo queue fills up.
2262 Specify the format name. Useful if it cannot be guessed from the
2266 Specify size of the queue (number of packets). Default value is 60.
2269 Specify format options for the underlying muxer. Muxer options can be specified
2270 as a list of @var{key}=@var{value} pairs separated by ':'.
2272 @item drop_pkts_on_overflow @var{bool}
2273 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
2274 rather than blocking the encoder. This makes it possible to continue streaming without
2275 delaying the input, at the cost of omitting part of the stream. By default
2276 this option is set to 0 (false), so in such cases the encoder will be blocked
2277 until the muxer processes some of the packets and none of them is lost.
2279 @item attempt_recovery @var{bool}
2280 If failure occurs, attempt to recover the output. This is especially useful
2281 when used with network output, since it makes it possible to restart streaming transparently.
2282 By default this option is set to 0 (false).
2284 @item max_recovery_attempts
2285 Sets maximum number of successive unsuccessful recovery attempts after which
2286 the output fails permanently. By default this option is set to 0 (unlimited).
2288 @item recovery_wait_time @var{duration}
2289 Waiting time before the next recovery attempt after previous unsuccessful
2290 recovery attempt. Default value is 5 seconds.
2292 @item recovery_wait_streamtime @var{bool}
2293 If set to 0 (false), the real time is used when waiting for the recovery
2294 attempt (i.e. the recovery will be attempted after at least
2295 recovery_wait_time seconds).
2296 If set to 1 (true), the time of the processed stream is taken into account
2297 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
2298 seconds of the stream is omitted).
2299 By default, this option is set to 0 (false).
2301 @item recover_any_error @var{bool}
2302 If set to 1 (true), recovery will be attempted regardless of type of the error
2303 causing the failure. By default this option is set to 0 (false) and in case of
2304 certain (usually permanent) errors the recovery is not attempted even when
2305 @var{attempt_recovery} is set to 1.
2307 @item restart_with_keyframe @var{bool}
2308 Specify whether to wait for the keyframe after recovering from
2309 queue overflow or failure. This option is set to 0 (false) by default.
2311 @item timeshift @var{duration}
2312 Buffer the specified amount of packets and delay writing the output. Note that
2313 @var{queue_size} must be big enough to store the packets for timeshift. At the
2314 end of the input the fifo buffer is flushed at realtime speed.
2318 @subsection Examples
2323 Stream something to rtmp server, continue processing the stream at real-time
2324 rate even in case of temporary failure (network outage) and attempt to recover
2325 streaming every second indefinitely.
2327 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
2328 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
2336 The tee muxer can be used to write the same data to several outputs, such as files or streams.
2337 It can be used, for example, to stream a video over a network and save it to disk at the same time.
2339 It is different from specifying several outputs to the @command{ffmpeg}
2340 command-line tool. With the tee muxer, the audio and video data will be encoded only once.
2341 With conventional multiple outputs, multiple encoding operations in parallel are initiated,
2342 which can be a very expensive process. The tee muxer is not useful when using the libavformat API
2343 directly because it is then possible to feed the same packets to several muxers directly.
2345 Since the tee muxer does not represent any particular output format, ffmpeg cannot auto-select
2346 output streams. So all streams intended for output must be specified using @code{-map}. See
2349 Some encoders may need different options depending on the output format;
2350 the auto-detection of this can not work with the tee muxer, so they need to be explicitly specified.
2351 The main example is the @option{global_header} flag.
2353 The slave outputs are specified in the file name given to the muxer,
2354 separated by '|'. If any of the slave name contains the '|' separator,
2355 leading or trailing spaces or any special character, those must be
2356 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
2357 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
2363 @item use_fifo @var{bool}
2364 If set to 1, slave outputs will be processed in separate threads using the @ref{fifo}
2365 muxer. This allows to compensate for different speed/latency/reliability of
2366 outputs and setup transparent recovery. By default this feature is turned off.
2369 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
2373 Muxer options can be specified for each slave by prepending them as a list of
2374 @var{key}=@var{value} pairs separated by ':', between square brackets. If
2375 the options values contain a special character or the ':' separator, they
2376 must be escaped; note that this is a second level escaping.
2378 The following special options are also recognized:
2381 Specify the format name. Required if it cannot be guessed from the
2384 @item bsfs[/@var{spec}]
2385 Specify a list of bitstream filters to apply to the specified
2388 It is possible to specify to which streams a given bitstream filter
2389 applies, by appending a stream specifier to the option separated by
2390 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
2391 stream specifiers}).
2393 If the stream specifier is not specified, the bitstream filters will be
2394 applied to all streams in the output. This will cause that output operation
2395 to fail if the output contains streams to which the bitstream filter cannot
2396 be applied e.g. @code{h264_mp4toannexb} being applied to an output containing an audio stream.
2398 Options for a bitstream filter must be specified in the form of @code{opt=value}.
2400 Several bitstream filters can be specified, separated by ",".
2402 @item use_fifo @var{bool}
2403 This allows to override tee muxer use_fifo option for individual slave muxer.
2406 This allows to override tee muxer fifo_options for individual slave muxer.
2410 Select the streams that should be mapped to the slave output,
2411 specified by a stream specifier. If not specified, this defaults to
2412 all the mapped streams. This will cause that output operation to fail
2413 if the output format does not accept all mapped streams.
2415 You may use multiple stream specifiers separated by commas (@code{,}) e.g.: @code{a:0,v}
2418 Specify behaviour on output failure. This can be set to either @code{abort} (which is
2419 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
2420 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
2421 will continue without being affected.
2424 @subsection Examples
2428 Encode something and both archive it in a WebM file and stream it
2429 as MPEG-TS over UDP:
2431 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2432 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2436 As above, but continue streaming even if output to local file fails
2437 (for example local drive fills up):
2439 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2440 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2444 Use @command{ffmpeg} to encode the input, and send the output
2445 to three different destinations. The @code{dump_extra} bitstream
2446 filter is used to add extradata information to all the output video
2447 keyframes packets, as requested by the MPEG-TS format. The select
2448 option is applied to @file{out.aac} in order to make it contain only
2451 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2452 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
2456 As above, but select only stream @code{a:1} for the audio output. Note
2457 that a second level escaping must be performed, as ":" is a special
2458 character used to separate options.
2460 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2461 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
2465 @section webm_dash_manifest
2467 WebM DASH Manifest muxer.
2469 This muxer implements the WebM DASH Manifest specification to generate the DASH
2470 manifest XML. It also supports manifest generation for DASH live streams.
2472 For more information see:
2476 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
2478 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
2483 This muxer supports the following options:
2486 @item adaptation_sets
2487 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
2488 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
2489 audio and video streams. Any number of adaptation sets can be added using this option.
2492 Set this to 1 to create a live stream DASH Manifest. Default: 0.
2494 @item chunk_start_index
2495 Start index of the first chunk. This will go in the @samp{startNumber} attribute
2496 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
2498 @item chunk_duration_ms
2499 Duration of each chunk in milliseconds. This will go in the @samp{duration}
2500 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
2502 @item utc_timing_url
2503 URL of the page that will return the UTC timestamp in ISO format. This will go
2504 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
2507 @item time_shift_buffer_depth
2508 Smallest time (in seconds) shifting buffer for which any Representation is
2509 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
2510 attribute of the @samp{MPD} element. Default: 60.
2512 @item minimum_update_period
2513 Minimum update period (in seconds) of the manifest. This will go in the
2514 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
2520 ffmpeg -f webm_dash_manifest -i video1.webm \
2521 -f webm_dash_manifest -i video2.webm \
2522 -f webm_dash_manifest -i audio1.webm \
2523 -f webm_dash_manifest -i audio2.webm \
2524 -map 0 -map 1 -map 2 -map 3 \
2526 -f webm_dash_manifest \
2527 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
2533 WebM Live Chunk Muxer.
2535 This muxer writes out WebM headers and chunks as separate files which can be
2536 consumed by clients that support WebM Live streams via DASH.
2540 This muxer supports the following options:
2543 @item chunk_start_index
2544 Index of the first chunk (defaults to 0).
2547 Filename of the header where the initialization data will be written.
2549 @item audio_chunk_duration
2550 Duration of each audio chunk in milliseconds (defaults to 5000).
2555 ffmpeg -f v4l2 -i /dev/video0 \
2559 -s 640x360 -keyint_min 30 -g 30 \
2561 -header webm_live_video_360.hdr \
2562 -chunk_start_index 1 \
2563 webm_live_video_360_%d.chk \
2568 -header webm_live_audio_128.hdr \
2569 -chunk_start_index 1 \
2570 -audio_chunk_duration 1000 \
2571 webm_live_audio_128_%d.chk