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 @var{use_timeline} is disabled and as minimum segment duration for all the other
247 @item frag_duration @var{duration}
248 Set the length in seconds of fragments within segments (fractional value can be set).
249 @item frag_type @var{type}
250 Set the type of interval for fragmentation.
251 @item window_size @var{size}
252 Set the maximum number of segments kept in the manifest.
253 @item extra_window_size @var{size}
254 Set the maximum number of segments kept outside of the manifest before removing from disk.
255 @item remove_at_exit @var{remove}
256 Enable (1) or disable (0) removal of all segments when finished.
257 @item use_template @var{template}
258 Enable (1) or disable (0) use of SegmentTemplate instead of SegmentList.
259 @item use_timeline @var{timeline}
260 Enable (1) or disable (0) use of SegmentTimeline in SegmentTemplate.
261 @item single_file @var{single_file}
262 Enable (1) or disable (0) storing all segments in one file, accessed using byte ranges.
263 @item single_file_name @var{file_name}
264 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.
265 @item init_seg_name @var{init_name}
266 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.
267 @item media_seg_name @var{segment_name}
268 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.
269 @item utc_timing_url @var{utc_url}
270 URL of the page that will return the UTC timestamp in ISO format. Example: "https://time.akamai.com/?iso"
271 @item method @var{method}
272 Use the given HTTP method to create output files. Generally set to PUT or POST.
273 @item http_user_agent @var{user_agent}
274 Override User-Agent field in HTTP header. Applicable only for HTTP output.
275 @item http_persistent @var{http_persistent}
276 Use persistent HTTP connections. Applicable only for HTTP output.
277 @item hls_playlist @var{hls_playlist}
278 Generate HLS playlist files as well. The master playlist is generated with the filename @var{hls_master_name}.
279 One media playlist file is generated for each stream with filenames media_0.m3u8, media_1.m3u8, etc.
280 @item hls_master_name @var{file_name}
281 HLS master playlist name. Default is "master.m3u8".
282 @item streaming @var{streaming}
283 Enable (1) or disable (0) chunk streaming mode of output. In chunk streaming
284 mode, each frame will be a moof fragment which forms a chunk.
285 @item adaptation_sets @var{adaptation_sets}
286 Assign streams to AdaptationSets. Syntax is "id=x,streams=a,b,c id=y,streams=d,e" with x and y being the IDs
287 of the adaptation sets and a,b,c,d and e are the indices of the mapped streams.
289 To map all video (or audio) streams to an AdaptationSet, "v" (or "a") can be used as stream identifier instead of IDs.
291 When no assignment is defined, this defaults to an AdaptationSet for each stream.
293 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,
294 descriptor is useful to the scheme defined by ISO/IEC 23009-1:2014/Amd.2:2015.
295 For example, -adaptation_sets "id=0,descriptor=<SupplementalProperty schemeIdUri=\"urn:mpeg:dash:srd:2014\" value=\"0,0,0,1,1,2,2\"/>,streams=v".
296 Please note that descriptor string should be a self-closing xml tag.
297 seg_duration, frag_duration and frag_type override the global option values for each adaptation set.
298 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"
299 type_id marks an adaptation set as containing streams meant to be used for Trick Mode for the referenced adaptation set.
300 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"
301 @item timeout @var{timeout}
302 Set timeout for socket I/O operations. Applicable only for HTTP output.
303 @item index_correction @var{index_correction}
304 Enable (1) or Disable (0) segment index correction logic. Applicable only when
305 @var{use_template} is enabled and @var{use_timeline} is disabled.
307 When enabled, the logic monitors the flow of segment indexes. If a streams's
308 segment index value is not at the expected real time position, then the logic
309 corrects that index value.
311 Typically this logic is needed in live streaming use cases. The network bandwidth
312 fluctuations are common during long run streaming. Each fluctuation can cause
313 the segment indexes fall behind the expected real time position.
314 @item format_options @var{options_list}
315 Set container format (mp4/webm) options using a @code{:} separated list of
316 key=value parameters. Values containing @code{:} special characters must be
319 @item global_sidx @var{global_sidx}
320 Write global SIDX atom. Applicable only for single file, mp4 output, non-streaming mode.
322 @item dash_segment_type @var{dash_segment_type}
326 If this flag is set, the dash segment files format will be selected based on the stream codec. This is the default mode.
329 If this flag is set, the dash segment files will be in in ISOBMFF format.
332 If this flag is set, the dash segment files will be in in WebM format.
335 @item ignore_io_errors @var{ignore_io_errors}
336 Ignore IO errors during open and write. Useful for long-duration runs with network output.
338 @item lhls @var{lhls}
339 Enable Low-latency HLS(LHLS). Adds #EXT-X-PREFETCH tag with current segment's URI.
340 Apple doesn't have an official spec for LHLS. Meanwhile hls.js player folks are
341 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
342 This option will also try to comply with the above open spec, till Apple's spec officially supports it.
343 Applicable only when @var{streaming} and @var{hls_playlist} options are enabled.
344 This is an experimental feature.
346 @item ldash @var{ldash}
347 Enable Low-latency Dash by constraining the presence and values of some elements.
349 @item master_m3u8_publish_rate @var{master_m3u8_publish_rate}
350 Publish master playlist repeatedly every after specified number of segment intervals.
352 @item write_prft @var{write_prft}
353 Write Producer Reference Time elements on supported streams. This also enables writing
354 prft boxes in the underlying muxer. Applicable only when the @var{utc_url} option is enabled.
355 It's set to auto by default, in which case the muxer will attempt to enable it only in modes
358 @item mpd_profile @var{mpd_profile}
359 Set one or more manifest profiles.
361 @item http_opts @var{http_opts}
362 A :-separated list of key=value options to pass to the underlying HTTP
363 protocol. Applicable only for HTTP output.
365 @item target_latency @var{target_latency}
366 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.
367 This is an informative fields clients can use to measure the latency of the service.
369 @item min_playback_rate @var{min_playback_rate}
370 Set the minimum playback rate indicated as appropriate for the purposes of automatically
371 adjusting playback latency and buffer occupancy during normal playback by clients.
373 @item max_playback_rate @var{max_playback_rate}
374 Set the maximum playback rate indicated as appropriate for the purposes of automatically
375 adjusting playback latency and buffer occupancy during normal playback by clients.
377 @item update_period @var{update_period}
378 Set the mpd update period ,for dynamic content.
386 Per-packet CRC (Cyclic Redundancy Check) testing format.
388 This muxer computes and prints the Adler-32 CRC for each audio
389 and video packet. By default audio frames are converted to signed
390 16-bit raw audio and video frames to raw video before computing the
393 The output of the muxer consists of a line for each audio and video
396 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
399 @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
404 For example to compute the CRC of the audio and video frames in
405 @file{INPUT}, converted to raw audio and video packets, and store it
406 in the file @file{out.crc}:
408 ffmpeg -i INPUT -f framecrc out.crc
411 To print the information to stdout, use the command:
413 ffmpeg -i INPUT -f framecrc -
416 With @command{ffmpeg}, you can select the output format to which the
417 audio and video frames are encoded before computing the CRC for each
418 packet by specifying the audio and video codec. For example, to
419 compute the CRC of each decoded input audio frame converted to PCM
420 unsigned 8-bit and of each decoded input video frame converted to
421 MPEG-2 video, use the command:
423 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
426 See also the @ref{crc} muxer.
431 Per-packet hash testing format.
433 This muxer computes and prints a cryptographic hash for each audio
434 and video packet. This can be used for packet-by-packet equality
435 checks without having to individually do a binary comparison on each.
437 By default audio frames are converted to signed 16-bit raw audio and
438 video frames to raw video before computing the hash, but the output
439 of explicit conversions to other codecs can also be used. It uses the
440 SHA-256 cryptographic hash function by default, but supports several
443 The output of the muxer consists of a line for each audio and video
446 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
449 @var{hash} is a hexadecimal number representing the computed hash
453 @item hash @var{algorithm}
454 Use the cryptographic hash function specified by the string @var{algorithm}.
455 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
456 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
457 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
458 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
464 To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
465 converted to raw audio and video packets, and store it in the file
468 ffmpeg -i INPUT -f framehash out.sha256
471 To print the information to stdout, using the MD5 hash function, use
474 ffmpeg -i INPUT -f framehash -hash md5 -
477 See also the @ref{hash} muxer.
482 Per-packet MD5 testing format.
484 This is a variant of the @ref{framehash} muxer. Unlike that muxer,
485 it defaults to using the MD5 hash function.
489 To compute the MD5 hash of the audio and video frames in @file{INPUT},
490 converted to raw audio and video packets, and store it in the file
493 ffmpeg -i INPUT -f framemd5 out.md5
496 To print the information to stdout, use the command:
498 ffmpeg -i INPUT -f framemd5 -
501 See also the @ref{framehash} and @ref{md5} muxers.
508 It accepts the following options:
512 Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
513 for looping indefinitely (default).
516 Force the delay (expressed in centiseconds) after the last frame. Each frame
517 ends with a delay until the next frame. The default is @code{-1}, which is a
518 special value to tell the muxer to re-use the previous delay. In case of a
519 loop, you might want to customize this value to mark a pause for instance.
522 For example, to encode a gif looping 10 times, with a 5 seconds delay between
525 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
528 Note 1: if you wish to extract the frames into separate GIF files, you need to
529 force the @ref{image2} muxer:
531 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
534 Note 2: the GIF format has a very large time base: the delay between two frames
535 can therefore not be smaller than one centi second.
542 This muxer computes and prints a cryptographic hash of all the input
543 audio and video frames. This can be used for equality checks without
544 having to do a complete binary comparison.
546 By default audio frames are converted to signed 16-bit raw audio and
547 video frames to raw video before computing the hash, but the output
548 of explicit conversions to other codecs can also be used. Timestamps
549 are ignored. It uses the SHA-256 cryptographic hash function by default,
550 but supports several other algorithms.
552 The output of the muxer consists of a single line of the form:
553 @var{algo}=@var{hash}, where @var{algo} is a short string representing
554 the hash function used, and @var{hash} is a hexadecimal number
555 representing the computed hash.
558 @item hash @var{algorithm}
559 Use the cryptographic hash function specified by the string @var{algorithm}.
560 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
561 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
562 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
563 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
569 To compute the SHA-256 hash of the input converted to raw audio and
570 video, and store it in the file @file{out.sha256}:
572 ffmpeg -i INPUT -f hash out.sha256
575 To print an MD5 hash to stdout use the command:
577 ffmpeg -i INPUT -f hash -hash md5 -
580 See also the @ref{framehash} muxer.
585 Apple HTTP Live Streaming muxer that segments MPEG-TS according to
586 the HTTP Live Streaming (HLS) specification.
588 It creates a playlist file, and one or more segment files. The output filename
589 specifies the playlist filename.
591 By default, the muxer creates a file for each segment produced. These files
592 have the same name as the playlist, followed by a sequential number and a
595 Make sure to require a closed GOP when encoding and to set the GOP
596 size to fit your segment time constraint.
598 For example, to convert an input file with @command{ffmpeg}:
600 ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
602 This example will produce the playlist, @file{out.m3u8}, and segment files:
603 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
605 See also the @ref{segment} muxer, which provides a more generic and
606 flexible implementation of a segmenter, and can be used to perform HLS
611 This muxer supports the following options:
614 @item hls_init_time @var{duration}
615 Set the initial target segment length. Default value is @var{0}.
617 @var{duration} must be a time duration specification,
618 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
620 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
621 After the initial playlist is filled @command{ffmpeg} will cut segments
622 at duration equal to @code{hls_time}
624 @item hls_time @var{duration}
625 Set the target segment length. Default value is 2.
627 @var{duration} must be a time duration specification,
628 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
629 Segment will be cut on the next key frame after this time has passed.
631 @item hls_list_size @var{size}
632 Set the maximum number of playlist entries. If set to 0 the list file
633 will contain all the segments. Default value is 5.
635 @item hls_delete_threshold @var{size}
636 Set the number of unreferenced segments to keep on disk before @code{hls_flags delete_segments}
637 deletes them. Increase this to allow continue clients to download segments which
638 were recently referenced in the playlist. Default value is 1, meaning segments older than
639 @code{hls_list_size+1} will be deleted.
641 @item hls_ts_options @var{options_list}
642 Set output format options using a :-separated list of key=value
643 parameters. Values containing @code{:} special characters must be
646 @item hls_wrap @var{wrap}
647 This is a deprecated option, you can use @code{hls_list_size}
648 and @code{hls_flags delete_segments} instead it
650 This option is useful to avoid to fill the disk with many segment
651 files, and limits the maximum number of segment files written to disk
655 @item hls_start_number_source
656 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
657 Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
658 segment and subtitle filenames. In any case, if @code{hls_flags append_list}
659 is set and read playlist sequence number is greater than the specified start sequence number,
660 then that value will be used as start value.
662 It accepts the following values:
666 @item generic (default)
667 Set the starting sequence numbers according to @var{start_number} option value.
670 The start number will be the seconds since epoch (1970-01-01 00:00:00)
673 The start number will be the microseconds since epoch (1970-01-01 00:00:00)
676 The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
680 @item start_number @var{number}
681 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
682 when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
683 Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
686 @item hls_allow_cache @var{allowcache}
687 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
689 @item hls_base_url @var{baseurl}
690 Append @var{baseurl} to every entry in the playlist.
691 Useful to generate playlists with absolute paths.
693 Note that the playlist sequence number must be unique for each segment
694 and it is not to be confused with the segment filename sequence number
695 which can be cyclic, for example if the @option{wrap} option is
698 @item hls_segment_filename @var{filename}
699 Set the segment filename. Unless @code{hls_flags single_file} is set,
700 @var{filename} is used as a string format with the segment number:
702 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
704 This example will produce the playlist, @file{out.m3u8}, and segment files:
705 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
707 @var{filename} may contain full path or relative path specification,
708 but only the file name part without any path info will be contained in the m3u8 segment list.
709 Should a relative path be specified, the path of the created segment
710 files will be relative to the current working directory.
711 When strftime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
713 When @code{var_stream_map} is set with two or more variant streams, the
714 @var{filename} pattern must contain the string "%v", this string specifies
715 the position of variant stream index in the generated segment file names.
717 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
718 -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" \
719 -hls_segment_filename 'file_%v_%03d.ts' out_%v.m3u8
721 This example will produce the playlists segment file sets:
722 @file{file_0_000.ts}, @file{file_0_001.ts}, @file{file_0_002.ts}, etc. and
723 @file{file_1_000.ts}, @file{file_1_001.ts}, @file{file_1_002.ts}, etc.
725 The string "%v" may be present in the filename or in the last directory name
726 containing the file, but only in one of them. (Additionally, %v may appear multiple times in the last
727 sub-directory or filename.) If the string %v is present in the directory name, then
728 sub-directories are created after expanding the directory name pattern. This
729 enables creation of segments corresponding to different variant streams in
732 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
733 -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" \
734 -hls_segment_filename 'vs%v/file_%03d.ts' vs%v/out.m3u8
736 This example will produce the playlists segment file sets:
737 @file{vs0/file_000.ts}, @file{vs0/file_001.ts}, @file{vs0/file_002.ts}, etc. and
738 @file{vs1/file_000.ts}, @file{vs1/file_001.ts}, @file{vs1/file_002.ts}, etc.
741 Same as strftime option, will be deprecated.
744 Use strftime() on @var{filename} to expand the segment filename with localtime.
745 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
746 hls_flag and %%d will be the specifier.
748 ffmpeg -i in.nut -strftime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
750 This example will produce the playlist, @file{out.m3u8}, and segment files:
751 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
752 Note: On some systems/environments, the @code{%s} specifier is not available. See
753 @code{strftime()} documentation.
755 ffmpeg -i in.nut -strftime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
757 This example will produce the playlist, @file{out.m3u8}, and segment files:
758 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
760 @item use_localtime_mkdir
761 Same as strftime_mkdir option, will be deprecated .
764 Used together with -strftime_mkdir, it will create all subdirectories which
765 is expanded in @var{filename}.
767 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y%m%d/file-%Y%m%d-%s.ts' out.m3u8
769 This example will create a directory 201560215 (if it does not exist), and then
770 produce the playlist, @file{out.m3u8}, and segment files:
771 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
774 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y/%m/%d/file-%Y%m%d-%s.ts' out.m3u8
776 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
777 produce the playlist, @file{out.m3u8}, and segment files:
778 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
781 @item hls_key_info_file @var{key_info_file}
782 Use the information in @var{key_info_file} for segment encryption. The first
783 line of @var{key_info_file} specifies the key URI written to the playlist. The
784 key URL is used to access the encryption key during playback. The second line
785 specifies the path to the key file used to obtain the key during the encryption
786 process. The key file is read as a single packed array of 16 octets in binary
787 format. The optional third line specifies the initialization vector (IV) as a
788 hexadecimal string to be used instead of the segment sequence number (default)
789 for encryption. Changes to @var{key_info_file} will result in segment
790 encryption with the new key/IV and an entry in the playlist for the new key
791 URI/IV if @code{hls_flags periodic_rekey} is enabled.
793 Key info file format:
802 http://server/file.key
807 Example key file paths:
815 0123456789ABCDEF0123456789ABCDEF
818 Key info file example:
820 http://server/file.key
822 0123456789ABCDEF0123456789ABCDEF
825 Example shell script:
829 openssl rand 16 > file.key
830 echo $BASE_URL/file.key > file.keyinfo
831 echo file.key >> file.keyinfo
832 echo $(openssl rand -hex 16) >> file.keyinfo
833 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
834 -hls_key_info_file file.keyinfo out.m3u8
837 @item -hls_enc @var{enc}
838 Enable (1) or disable (0) the AES128 encryption.
839 When enabled every segment generated is encrypted and the encryption key
840 is saved as @var{playlist name}.key.
842 @item -hls_enc_key @var{key}
843 16-octet key to encrypt the segments, by default it
844 is randomly generated.
846 @item -hls_enc_key_url @var{keyurl}
847 If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
850 @item -hls_enc_iv @var{iv}
851 16-octet initialization vector for every segment instead
852 of the autogenerated ones.
854 @item hls_segment_type @var{flags}
859 Output segment files in MPEG-2 Transport Stream format. This is
860 compatible with all HLS versions.
863 Output segment files in fragmented MP4 format, similar to MPEG-DASH.
864 fmp4 files may be used in HLS version 7 and above.
868 @item hls_fmp4_init_filename @var{filename}
869 Set filename to the fragment files header file, default filename is @file{init.mp4}.
871 Use @code{-strftime 1} on @var{filename} to expand the segment filename with localtime.
873 ffmpeg -i in.nut -hls_segment_type fmp4 -strftime 1 -hls_fmp4_init_filename "%s_init.mp4" out.m3u8
875 This will produce init like this
876 @file{1602678741_init.mp4}
878 @item hls_fmp4_init_resend
879 Resend init file after m3u8 file refresh every time, default is @var{0}.
881 When @code{var_stream_map} is set with two or more variant streams, the
882 @var{filename} pattern must contain the string "%v", this string specifies
883 the position of variant stream index in the generated init file names.
884 The string "%v" may be present in the filename or in the last directory name
885 containing the file. If the string is present in the directory name, then
886 sub-directories are created after expanding the directory name pattern. This
887 enables creation of init files corresponding to different variant streams in
890 @item hls_flags @var{flags}
895 If this flag is set, the muxer will store all segments in a single MPEG-TS
896 file, and will use byte ranges in the playlist. HLS playlists generated with
897 this way will have the version number 4.
900 ffmpeg -i in.nut -hls_flags single_file out.m3u8
902 Will produce the playlist, @file{out.m3u8}, and a single segment file,
905 @item delete_segments
906 Segment files removed from the playlist are deleted after a period of time
907 equal to the duration of the segment plus the duration of the playlist.
910 Append new segments into the end of old segment list,
911 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
913 @item round_durations
914 Round the duration info in the playlist file segment info to integer
915 values, instead of using floating point.
918 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
919 first segment's information.
922 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
925 The file specified by @code{hls_key_info_file} will be checked periodically and
926 detect updates to the encryption info. Be sure to replace this file atomically,
927 including the file containing the AES encryption key.
929 @item independent_segments
930 Add the @code{#EXT-X-INDEPENDENT-SEGMENTS} to playlists that has video segments
931 and when all the segments of that playlist are guaranteed to start with a Key frame.
934 Add the @code{#EXT-X-I-FRAMES-ONLY} to playlists that has video segments
935 and can play only I-frames in the @code{#EXT-X-BYTERANGE} mode.
938 Allow segments to start on frames other than keyframes. This improves
939 behavior on some players when the time between keyframes is inconsistent,
940 but may make things worse on others, and can cause some oddities during
941 seeking. This flag should be used with the @code{hls_time} option.
943 @item program_date_time
944 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
946 @item second_level_segment_index
947 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
948 besides date/time values when strftime is on.
949 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
951 @item second_level_segment_size
952 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
953 expression besides date/time values when strftime is on.
954 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
956 @item second_level_segment_duration
957 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
958 expression besides date/time values when strftime is on.
959 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
962 ffmpeg -i sample.mpeg \
963 -f hls -hls_time 3 -hls_list_size 5 \
964 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
965 -strftime 1 -strftime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
967 This will produce segments like this:
968 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
971 Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
972 serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
973 before they have been added to the m3u8 playlist. This flag also affects how m3u8 playlist files are created.
974 If this flag is set, all playlist files will written into temporary file and renamed after they are complete, similarly as segments are handled.
975 But playlists with @code{file} protocol and with type (@code{hls_playlist_type}) other than @code{vod}
976 are always written into temporary file regardless of this flag. Master playlist files (@code{master_pl_name}), if any, with @code{file} protocol,
977 are always written into temporary file regardless of this flag if @code{master_pl_publish_rate} value is other than zero.
981 @item hls_playlist_type event
982 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
983 @option{hls_list_size} to 0; the playlist can only be appended to.
985 @item hls_playlist_type vod
986 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
987 @option{hls_list_size} to 0; the playlist must not change.
990 Use the given HTTP method to create the hls files.
992 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
994 This example will upload all the mpegts segment files to the HTTP
995 server using the HTTP PUT method, and update the m3u8 files every
996 @code{refresh} times using the same method.
997 Note that the HTTP server must support the given method for uploading
1000 @item http_user_agent
1001 Override User-Agent field in HTTP header. Applicable only for HTTP output.
1003 @item var_stream_map
1004 Map string which specifies how to group the audio, video and subtitle streams
1005 into different variant streams. The variant stream groups are separated
1007 Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
1008 the keys to specify audio, video and subtitle streams respectively.
1009 Allowed values are 0 to 9 (limited just based on practical usage).
1011 When there are two or more variant streams, the output filename pattern must
1012 contain the string "%v", this string specifies the position of variant stream
1013 index in the output media playlist filenames. The string "%v" may be present in
1014 the filename or in the last directory name containing the file. If the string is
1015 present in the directory name, then sub-directories are created after expanding
1016 the directory name pattern. This enables creation of variant streams in
1020 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1021 -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" \
1022 http://example.com/live/out_%v.m3u8
1024 This example creates two hls variant streams. The first variant stream will
1025 contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
1026 second variant stream will contain video stream of bitrate 256k and audio
1027 stream of bitrate 32k. Here, two media playlist with file names out_0.m3u8 and
1028 out_1.m3u8 will be created. If you want something meaningful text instead of indexes
1029 in result names, you may specify names for each or some of the variants
1030 as in the following example.
1034 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1035 -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" \
1036 http://example.com/live/out_%v.m3u8
1039 This example creates two hls variant streams as in the previous one.
1040 But here, the two media playlist with file names out_my_hd.m3u8 and
1041 out_my_sd.m3u8 will be created.
1044 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
1045 -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
1046 http://example.com/live/out_%v.m3u8
1048 This example creates three hls variant streams. The first variant stream will
1049 be a video only stream with video bitrate 1000k, the second variant stream will
1050 be an audio only stream with bitrate 64k and the third variant stream will be a
1051 video only stream with bitrate 256k. Here, three media playlist with file names
1052 out_0.m3u8, out_1.m3u8 and out_2.m3u8 will be created.
1054 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1055 -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" \
1056 http://example.com/live/vs_%v/out.m3u8
1058 This example creates the variant streams in subdirectories. Here, the first
1059 media playlist is created at @file{http://example.com/live/vs_0/out.m3u8} and
1060 the second one at @file{http://example.com/live/vs_1/out.m3u8}.
1062 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k \
1063 -map 0:a -map 0:a -map 0:v -map 0:v -f hls \
1064 -var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
1065 -master_pl_name master.m3u8 \
1066 http://example.com/live/out_%v.m3u8
1068 This example creates two audio only and two video only variant streams. In
1069 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1070 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1071 and they are mapped to the two video only variant streams with audio group names
1072 'aud_low' and 'aud_high'.
1074 By default, a single hls variant containing all the encoded streams is created.
1077 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
1078 -map 0:a -map 0:a -map 0:v -f hls \
1079 -var_stream_map "a:0,agroup:aud_low,default:yes a:1,agroup:aud_low v:0,agroup:aud_low" \
1080 -master_pl_name master.m3u8 \
1081 http://example.com/live/out_%v.m3u8
1083 This example creates two audio only and one video only variant streams. In
1084 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1085 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1086 and they are mapped to the one video only variant streams with audio group name
1087 'aud_low', and the audio group have default stat is NO or YES.
1089 By default, a single hls variant containing all the encoded streams is created.
1092 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
1093 -map 0:a -map 0:a -map 0:v -f hls \
1094 -var_stream_map "a:0,agroup:aud_low,default:yes,language:ENG a:1,agroup:aud_low,language:CHN v:0,agroup:aud_low" \
1095 -master_pl_name master.m3u8 \
1096 http://example.com/live/out_%v.m3u8
1098 This example creates two audio only and one video only variant streams. In
1099 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1100 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1101 and they are mapped to the one video only variant streams with audio group name
1102 'aud_low', and the audio group have default stat is NO or YES, and one audio
1103 have and language is named ENG, the other audio language is named CHN.
1105 By default, a single hls variant containing all the encoded streams is created.
1108 ffmpeg -y -i input_with_subtitle.mkv \
1109 -b:v:0 5250k -c:v h264 -pix_fmt yuv420p -profile:v main -level 4.1 \
1111 -c:s webvtt -c:a mp2 -ar 48000 -ac 2 -map 0:v -map 0:a:0 -map 0:s:0 \
1112 -f hls -var_stream_map "v:0,a:0,s:0,sgroup:subtitle" \
1113 -master_pl_name master.m3u8 -t 300 -hls_time 10 -hls_init_time 4 -hls_list_size \
1114 10 -master_pl_publish_rate 10 -hls_flags \
1115 delete_segments+discont_start+split_by_time ./tmp/video.m3u8
1118 This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=SUBTITLES} in
1119 the master playlist with webvtt subtitle group name 'subtitle'. Please make sure
1120 the input file has one text subtitle stream at least.
1123 Map string which specifies different closed captions groups and their
1124 attributes. The closed captions stream groups are separated by space.
1125 Expected string format is like this
1126 "ccgroup:<group name>,instreamid:<INSTREAM-ID>,language:<language code> ....".
1127 'ccgroup' and 'instreamid' are mandatory attributes. 'language' is an optional
1129 The closed captions groups configured using this option are mapped to different
1130 variant streams by providing the same 'ccgroup' name in the
1131 @code{var_stream_map} string. If @code{var_stream_map} is not set, then the
1132 first available ccgroup in @code{cc_stream_map} is mapped to the output variant
1133 stream. The examples for these two use cases are given below.
1136 ffmpeg -re -i in.ts -b:v 1000k -b:a 64k -a53cc 1 -f hls \
1137 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en" \
1138 -master_pl_name master.m3u8 \
1139 http://example.com/live/out.m3u8
1141 This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=CLOSED-CAPTIONS} in
1142 the master playlist with group name 'cc', language 'en' (english) and
1143 INSTREAM-ID 'CC1'. Also, it adds @code{CLOSED-CAPTIONS} attribute with group
1144 name 'cc' for the output variant stream.
1146 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1147 -a53cc:0 1 -a53cc:1 1\
1148 -map 0:v -map 0:a -map 0:v -map 0:a -f hls \
1149 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en ccgroup:cc,instreamid:CC2,language:sp" \
1150 -var_stream_map "v:0,a:0,ccgroup:cc v:1,a:1,ccgroup:cc" \
1151 -master_pl_name master.m3u8 \
1152 http://example.com/live/out_%v.m3u8
1154 This example adds two @code{#EXT-X-MEDIA} tags with @code{TYPE=CLOSED-CAPTIONS} in
1155 the master playlist for the INSTREAM-IDs 'CC1' and 'CC2'. Also, it adds
1156 @code{CLOSED-CAPTIONS} attribute with group name 'cc' for the two output variant
1159 @item master_pl_name
1160 Create HLS master playlist with the given name.
1163 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
1165 This example creates HLS master playlist with name master.m3u8 and it is
1166 published at http://example.com/live/
1168 @item master_pl_publish_rate
1169 Publish master play list repeatedly every after specified number of segment intervals.
1172 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
1173 -hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
1176 This example creates HLS master playlist with name master.m3u8 and keep
1177 publishing it repeatedly every after 30 segments i.e. every after 60s.
1179 @item http_persistent
1180 Use persistent HTTP connections. Applicable only for HTTP output.
1183 Set timeout for socket I/O operations. Applicable only for HTTP output.
1185 @item -ignore_io_errors
1186 Ignore IO errors during open, write and delete. Useful for long-duration runs with network output.
1189 Set custom HTTP headers, can override built in default headers. Applicable only for HTTP output.
1198 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
1202 Size cannot exceed 256 pixels in any dimension
1205 Only BMP and PNG images can be stored
1208 If a BMP image is used, it must be one of the following pixel formats:
1210 BMP Bit Depth FFmpeg Pixel Format
1220 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
1223 If a PNG image is used, it must use the rgba pixel format
1231 The image file muxer writes video frames to image files.
1233 The output filenames are specified by a pattern, which can be used to
1234 produce sequentially numbered series of files.
1235 The pattern may contain the string "%d" or "%0@var{N}d", this string
1236 specifies the position of the characters representing a numbering in
1237 the filenames. If the form "%0@var{N}d" is used, the string
1238 representing the number in each filename is 0-padded to @var{N}
1239 digits. The literal character '%' can be specified in the pattern with
1242 If the pattern contains "%d" or "%0@var{N}d", the first filename of
1243 the file list specified will contain the number 1, all the following
1244 numbers will be sequential.
1246 The pattern may contain a suffix which is used to automatically
1247 determine the format of the image files to write.
1249 For example the pattern "img-%03d.bmp" will specify a sequence of
1250 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
1251 @file{img-010.bmp}, etc.
1252 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
1253 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
1256 The image muxer supports the .Y.U.V image file format. This format is
1257 special in that that each image frame consists of three files, for
1258 each of the YUV420P components. To read or write this image file format,
1259 specify the name of the '.Y' file. The muxer will automatically open the
1260 '.U' and '.V' files as required.
1266 If set to 1, expand the filename with pts from pkt->pts.
1270 Start the sequence from the specified number. Default value is 1.
1273 If set to 1, the filename will always be interpreted as just a
1274 filename, not a pattern, and the corresponding file will be continuously
1275 overwritten with new images. Default value is 0.
1278 If set to 1, expand the filename with date and time information from
1279 @code{strftime()}. Default value is 0.
1281 @item protocol_opts @var{options_list}
1282 Set protocol options as a :-separated list of key=value parameters. Values
1283 containing the @code{:} special character must be escaped.
1287 @subsection Examples
1289 The following example shows how to use @command{ffmpeg} for creating a
1290 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
1291 taking one image every second from the input video:
1293 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
1296 Note that with @command{ffmpeg}, if the format is not specified with the
1297 @code{-f} option and the output filename specifies an image file
1298 format, the image2 muxer is automatically selected, so the previous
1299 command can be written as:
1301 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
1304 Note also that the pattern must not necessarily contain "%d" or
1305 "%0@var{N}d", for example to create a single image file
1306 @file{img.jpeg} from the start of the input video you can employ the command:
1308 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
1311 The @option{strftime} option allows you to expand the filename with
1312 date and time information. Check the documentation of
1313 the @code{strftime()} function for the syntax.
1315 For example to generate image files from the @code{strftime()}
1316 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
1319 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
1322 You can set the file name with current frame's PTS:
1324 ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
1327 A more complex example is to publish contents of your desktop directly to a
1328 WebDAV server every second:
1330 ffmpeg -f x11grab -framerate 1 -i :0.0 -q:v 6 -update 1 -protocol_opts method=PUT http://example.com/desktop.jpg
1335 Matroska container muxer.
1337 This muxer implements the matroska and webm container specs.
1339 @subsection Metadata
1341 The recognized metadata settings in this muxer are:
1345 Set title name provided to a single track. This gets mapped to
1346 the FileDescription element for a stream written as attachment.
1349 Specify the language of the track in the Matroska languages form.
1351 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
1352 639-2/B) form (like "fre" for French), or a language code mixed with a
1353 country code for specialities in languages (like "fre-ca" for Canadian
1357 Set stereo 3D video layout of two views in a single video track.
1359 The following values are recognized:
1364 Both views are arranged side by side, Left-eye view is on the left
1366 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
1368 Both views are arranged in top-bottom orientation, Left-eye view is on top
1369 @item checkerboard_rl
1370 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
1371 @item checkerboard_lr
1372 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
1373 @item row_interleaved_rl
1374 Each view is constituted by a row based interleaving, Right-eye view is first row
1375 @item row_interleaved_lr
1376 Each view is constituted by a row based interleaving, Left-eye view is first row
1377 @item col_interleaved_rl
1378 Both views are arranged in a column based interleaving manner, Right-eye view is first column
1379 @item col_interleaved_lr
1380 Both views are arranged in a column based interleaving manner, Left-eye view is first column
1381 @item anaglyph_cyan_red
1382 All frames are in anaglyph format viewable through red-cyan filters
1384 Both views are arranged side by side, Right-eye view is on the left
1385 @item anaglyph_green_magenta
1386 All frames are in anaglyph format viewable through green-magenta filters
1388 Both eyes laced in one Block, Left-eye view is first
1390 Both eyes laced in one Block, Right-eye view is first
1394 For example a 3D WebM clip can be created using the following command line:
1396 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
1401 This muxer supports the following options:
1404 @item reserve_index_space
1405 By default, this muxer writes the index for seeking (called cues in Matroska
1406 terms) at the end of the file, because it cannot know in advance how much space
1407 to leave for the index at the beginning of the file. However for some use cases
1408 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
1409 index at the beginning of the file.
1411 If this option is set to a non-zero value, the muxer will reserve a given amount
1412 of space in the file header and then try to write the cues there when the muxing
1413 finishes. If the reserved space does not suffice, no Cues will be written, the
1414 file will be finalized and writing the trailer will return an error.
1415 A safe size for most use cases should be about 50kB per hour of video.
1417 Note that cues are only written if the output is seekable and this option will
1418 have no effect if it is not.
1420 This option controls how the FlagDefault of the output tracks will be set.
1421 It influences which tracks players should play by default. The default mode
1425 In this mode, for each type of track (audio, video or subtitle), if there is
1426 a track with disposition default of this type, then the first such track
1427 (i.e. the one with the lowest index) will be marked as default; if no such
1428 track exists, the first track of this type will be marked as default instead
1429 (if existing). This ensures that the default flag is set in a sensible way even
1430 if the input originated from containers that lack the concept of default tracks.
1432 This mode is the same as infer except that if no subtitle track with
1433 disposition default exists, no subtitle track will be marked as default.
1435 In this mode the FlagDefault is set if and only if the AV_DISPOSITION_DEFAULT
1436 flag is set in the disposition of the corresponding stream.
1439 @item flipped_raw_rgb
1440 If set to true, store positive height for raw RGB bitmaps, which indicates
1441 bitmap is stored bottom-up. Note that this option does not flip the bitmap
1442 which has to be done manually beforehand, e.g. by using the vflip filter.
1443 Default is @var{false} and indicates bitmap is stored top down.
1452 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
1453 defaults to using the MD5 hash function.
1455 @subsection Examples
1457 To compute the MD5 hash of the input converted to raw
1458 audio and video, and store it in the file @file{out.md5}:
1460 ffmpeg -i INPUT -f md5 out.md5
1463 You can print the MD5 to stdout with the command:
1465 ffmpeg -i INPUT -f md5 -
1468 See also the @ref{hash} and @ref{framemd5} muxers.
1470 @section mov, mp4, ismv
1472 MOV/MP4/ISMV (Smooth Streaming) muxer.
1474 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
1475 file has all the metadata about all packets stored in one location
1476 (written at the end of the file, it can be moved to the start for
1477 better playback by adding @var{faststart} to the @var{movflags}, or
1478 using the @command{qt-faststart} tool). A fragmented
1479 file consists of a number of fragments, where packets and metadata
1480 about these packets are stored together. Writing a fragmented
1481 file has the advantage that the file is decodable even if the
1482 writing is interrupted (while a normal MOV/MP4 is undecodable if
1483 it is not properly finished), and it requires less memory when writing
1484 very long files (since writing normal MOV/MP4 files stores info about
1485 every single packet in memory until the file is closed). The downside
1486 is that it is less compatible with other applications.
1490 Fragmentation is enabled by setting one of the AVOptions that define
1491 how to cut the file into fragments:
1494 @item -moov_size @var{bytes}
1495 Reserves space for the moov atom at the beginning of the file instead of placing the
1496 moov atom at the end. If the space reserved is insufficient, muxing will fail.
1497 @item -movflags frag_keyframe
1498 Start a new fragment at each video keyframe.
1499 @item -frag_duration @var{duration}
1500 Create fragments that are @var{duration} microseconds long.
1501 @item -frag_size @var{size}
1502 Create fragments that contain up to @var{size} bytes of payload data.
1503 @item -movflags frag_custom
1504 Allow the caller to manually choose when to cut fragments, by
1505 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
1506 the packets written so far. (This is only useful with other
1507 applications integrating libavformat, not from @command{ffmpeg}.)
1508 @item -min_frag_duration @var{duration}
1509 Don't create fragments that are shorter than @var{duration} microseconds long.
1512 If more than one condition is specified, fragments are cut when
1513 one of the specified conditions is fulfilled. The exception to this is
1514 @code{-min_frag_duration}, which has to be fulfilled for any of the other
1515 conditions to apply.
1517 Additionally, the way the output file is written can be adjusted
1518 through a few other options:
1521 @item -movflags empty_moov
1522 Write an initial moov atom directly at the start of the file, without
1523 describing any samples in it. Generally, an mdat/moov pair is written
1524 at the start of the file, as a normal MOV/MP4 file, containing only
1525 a short portion of the file. With this option set, there is no initial
1526 mdat atom, and the moov atom only describes the tracks but has
1529 This option is implicitly set when writing ismv (Smooth Streaming) files.
1530 @item -movflags separate_moof
1531 Write a separate moof (movie fragment) atom for each track. Normally,
1532 packets for all tracks are written in a moof atom (which is slightly
1533 more efficient), but with this option set, the muxer writes one moof/mdat
1534 pair for each track, making it easier to separate tracks.
1536 This option is implicitly set when writing ismv (Smooth Streaming) files.
1537 @item -movflags skip_sidx
1538 Skip writing of sidx atom. When bitrate overhead due to sidx atom is high,
1539 this option could be used for cases where sidx atom is not mandatory.
1540 When global_sidx flag is enabled, this option will be ignored.
1541 @item -movflags faststart
1542 Run a second pass moving the index (moov atom) to the beginning of the file.
1543 This operation can take a while, and will not work in various situations such
1544 as fragmented output, thus it is not enabled by default.
1545 @item -movflags rtphint
1546 Add RTP hinting tracks to the output file.
1547 @item -movflags disable_chpl
1548 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
1549 and a QuickTime chapter track are written to the file. With this option
1550 set, only the QuickTime chapter track will be written. Nero chapters can
1551 cause failures when the file is reprocessed with certain tagging programs, like
1552 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
1553 @item -movflags omit_tfhd_offset
1554 Do not write any absolute base_data_offset in tfhd atoms. This avoids
1555 tying fragments to absolute byte positions in the file/streams.
1556 @item -movflags default_base_moof
1557 Similarly to the omit_tfhd_offset, this flag avoids writing the
1558 absolute base_data_offset field in tfhd atoms, but does so by using
1559 the new default-base-is-moof flag instead. This flag is new from
1560 14496-12:2012. This may make the fragments easier to parse in certain
1561 circumstances (avoiding basing track fragment location calculations
1562 on the implicit end of the previous track fragment).
1564 Specify @code{on} to force writing a timecode track, @code{off} to disable it
1565 and @code{auto} to write a timecode track only for mov and mp4 output (default).
1566 @item -movflags negative_cts_offsets
1567 Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
1568 be negative. This enables the initial sample to have DTS/CTS of zero, and
1569 reduces the need for edit lists for some cases such as video tracks with
1570 B-frames. Additionally, eases conformance with the DASH-IF interoperability
1573 This option is implicitly set when writing ismv (Smooth Streaming) files.
1575 Write producer time reference box (PRFT) with a specified time source for the
1576 NTP field in the PRFT box. Set value as @samp{wallclock} to specify timesource
1577 as wallclock time and @samp{pts} to specify timesource as input packets' PTS
1580 Setting value to @samp{pts} is applicable only for a live encoding use case,
1581 where PTS values are set as as wallclock time at the source. For example, an
1582 encoding use case with decklink capture source where @option{video_pts} and
1583 @option{audio_pts} are set to @samp{abs_wallclock}.
1588 Smooth Streaming content can be pushed in real time to a publishing
1589 point on IIS with this muxer. Example:
1591 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
1596 The MP3 muxer writes a raw MP3 stream with the following optional features:
1599 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
1600 2.4 are supported, the @code{id3v2_version} private option controls which one is
1601 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
1604 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
1605 The pictures are supplied to the muxer in form of a video stream with a single
1606 packet. There can be any number of those streams, each will correspond to a
1607 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
1608 to APIC @var{description} and @var{picture type} respectively. See
1609 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
1611 Note that the APIC frames must be written at the beginning, so the muxer will
1612 buffer the audio frames until it gets all the pictures. It is therefore advised
1613 to provide the pictures as soon as possible to avoid excessive buffering.
1616 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
1617 default, but will be written only if the output is seekable. The
1618 @code{write_xing} private option can be used to disable it. The frame contains
1619 various information that may be useful to the decoder, like the audio duration
1623 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1624 enabled with the @code{write_id3v1} private option, but as its capabilities are
1625 very limited, its usage is not recommended.
1630 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1632 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1635 To attach a picture to an mp3 file select both the audio and the picture stream
1638 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1639 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1642 Write a "clean" MP3 without any extra features:
1644 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1649 MPEG transport stream muxer.
1651 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1653 The recognized metadata settings in mpegts muxer are @code{service_provider}
1654 and @code{service_name}. If they are not set the default for
1655 @code{service_provider} is @samp{FFmpeg} and the default for
1656 @code{service_name} is @samp{Service01}.
1660 The muxer options are:
1663 @item mpegts_transport_stream_id @var{integer}
1664 Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
1665 Default is @code{0x0001}.
1667 @item mpegts_original_network_id @var{integer}
1668 Set the @samp{original_network_id}. This is unique identifier of a
1669 network in DVB. Its main use is in the unique identification of a service
1670 through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
1673 @item mpegts_service_id @var{integer}
1674 Set the @samp{service_id}, also known as program in DVB. Default is
1677 @item mpegts_service_type @var{integer}
1678 Set the program @samp{service_type}. Default is @code{digital_tv}.
1679 Accepts the following options:
1682 Any hexadecimal value between @code{0x01} and @code{0xff} as defined in
1687 Digital Radio service.
1690 @item advanced_codec_digital_radio
1691 Advanced Codec Digital Radio service.
1692 @item mpeg2_digital_hdtv
1693 MPEG2 Digital HDTV service.
1694 @item advanced_codec_digital_sdtv
1695 Advanced Codec Digital SDTV service.
1696 @item advanced_codec_digital_hdtv
1697 Advanced Codec Digital HDTV service.
1700 @item mpegts_pmt_start_pid @var{integer}
1701 Set the first PID for PMTs. Default is @code{0x1000}, minimum is @code{0x0020},
1702 maximum is @code{0x1ffa}. This option has no effect in m2ts mode where the PMT
1703 PID is fixed @code{0x0100}.
1705 @item mpegts_start_pid @var{integer}
1706 Set the first PID for elementary streams. Default is @code{0x0100}, minimum is
1707 @code{0x0020}, maximum is @code{0x1ffa}. This option has no effect in m2ts mode
1708 where the elementary stream PIDs are fixed.
1710 @item mpegts_m2ts_mode @var{boolean}
1711 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
1714 @item muxrate @var{integer}
1715 Set a constant muxrate. Default is VBR.
1717 @item pes_payload_size @var{integer}
1718 Set minimum PES packet payload in bytes. Default is @code{2930}.
1720 @item mpegts_flags @var{flags}
1721 Set mpegts flags. Accepts the following options:
1723 @item resend_headers
1724 Reemit PAT/PMT before writing the next packet.
1726 Use LATM packetization for AAC.
1727 @item pat_pmt_at_frames
1728 Reemit PAT and PMT at each video frame.
1730 Conform to System B (DVB) instead of System A (ATSC).
1731 @item initial_discontinuity
1732 Mark the initial packet of each stream as discontinuity.
1735 @item mpegts_copyts @var{boolean}
1736 Preserve original timestamps, if value is set to @code{1}. Default value
1737 is @code{-1}, which results in shifting timestamps so that they start from 0.
1739 @item omit_video_pes_length @var{boolean}
1740 Omit the PES packet length for video packets. Default is @code{1} (true).
1742 @item pcr_period @var{integer}
1743 Override the default PCR retransmission time in milliseconds. Default is
1744 @code{-1} which means that the PCR interval will be determined automatically:
1745 20 ms is used for CBR streams, the highest multiple of the frame duration which
1746 is less than 100 ms is used for VBR streams.
1748 @item pat_period @var{duration}
1749 Maximum time in seconds between PAT/PMT tables. Default is @code{0.1}.
1751 @item sdt_period @var{duration}
1752 Maximum time in seconds between SDT tables. Default is @code{0.5}.
1754 @item tables_version @var{integer}
1755 Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
1756 This option allows updating stream structure so that standard consumer may
1757 detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
1758 usage) or restart @command{ffmpeg} instance, cyclically changing
1759 @option{tables_version} value:
1762 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1763 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1765 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1766 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1767 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1775 ffmpeg -i file.mpg -c copy \
1776 -mpegts_original_network_id 0x1122 \
1777 -mpegts_transport_stream_id 0x3344 \
1778 -mpegts_service_id 0x5566 \
1779 -mpegts_pmt_start_pid 0x1500 \
1780 -mpegts_start_pid 0x150 \
1781 -metadata service_provider="Some provider" \
1782 -metadata service_name="Some Channel" \
1786 @section mxf, mxf_d10, mxf_opatom
1792 The muxer options are:
1795 @item store_user_comments @var{bool}
1796 Set if user comments should be stored if available or never.
1797 IRT D-10 does not allow user comments. The default is thus to write them for
1798 mxf and mxf_opatom but not for mxf_d10
1805 This muxer does not generate any output file, it is mainly useful for
1806 testing or benchmarking purposes.
1808 For example to benchmark decoding with @command{ffmpeg} you can use the
1811 ffmpeg -benchmark -i INPUT -f null out.null
1814 Note that the above command does not read or write the @file{out.null}
1815 file, but specifying the output file is required by the @command{ffmpeg}
1818 Alternatively you can write the command as:
1820 ffmpeg -benchmark -i INPUT -f null -
1826 @item -syncpoints @var{flags}
1827 Change the syncpoint usage in nut:
1829 @item @var{default} use the normal low-overhead seeking aids.
1830 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1831 Use of this option is not recommended, as the resulting files are very damage
1832 sensitive and seeking is not possible. Also in general the overhead from
1833 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1834 all growing data tables, allowing to mux endless streams with limited memory
1835 and without these disadvantages.
1836 @item @var{timestamped} extend the syncpoint with a wallclock field.
1838 The @var{none} and @var{timestamped} flags are experimental.
1839 @item -write_index @var{bool}
1840 Write index at the end, the default is to write an index.
1844 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1849 Ogg container muxer.
1852 @item -page_duration @var{duration}
1853 Preferred page duration, in microseconds. The muxer will attempt to create
1854 pages that are approximately @var{duration} microseconds long. This allows the
1855 user to compromise between seek granularity and container overhead. The default
1856 is 1 second. A value of 0 will fill all segments, making pages as large as
1857 possible. A value of 1 will effectively use 1 packet-per-page in most
1858 situations, giving a small seek granularity at the cost of additional container
1860 @item -serial_offset @var{value}
1861 Serial value from which to set the streams serial number.
1862 Setting it to different and sufficiently large values ensures that the produced
1863 ogg files can be safely chained.
1868 @section segment, stream_segment, ssegment
1870 Basic stream segmenter.
1872 This muxer outputs streams to a number of separate files of nearly
1873 fixed duration. Output filename pattern can be set in a fashion
1874 similar to @ref{image2}, or by using a @code{strftime} template if
1875 the @option{strftime} option is enabled.
1877 @code{stream_segment} is a variant of the muxer used to write to
1878 streaming output formats, i.e. which do not require global headers,
1879 and is recommended for outputting e.g. to MPEG transport stream segments.
1880 @code{ssegment} is a shorter alias for @code{stream_segment}.
1882 Every segment starts with a keyframe of the selected reference stream,
1883 which is set through the @option{reference_stream} option.
1885 Note that if you want accurate splitting for a video file, you need to
1886 make the input key frames correspond to the exact splitting times
1887 expected by the segmenter, or the segment muxer will start the new
1888 segment with the key frame found next after the specified start
1891 The segment muxer works best with a single constant frame rate video.
1893 Optionally it can generate a list of the created segments, by setting
1894 the option @var{segment_list}. The list type is specified by the
1895 @var{segment_list_type} option. The entry filenames in the segment
1896 list are set by default to the basename of the corresponding segment
1899 See also the @ref{hls} muxer, which provides a more specific
1900 implementation for HLS segmentation.
1904 The segment muxer supports the following options:
1907 @item increment_tc @var{1|0}
1908 if set to @code{1}, increment timecode between each segment
1909 If this is selected, the input need to have
1910 a timecode in the first video stream. Default value is
1913 @item reference_stream @var{specifier}
1914 Set the reference stream, as specified by the string @var{specifier}.
1915 If @var{specifier} is set to @code{auto}, the reference is chosen
1916 automatically. Otherwise it must be a stream specifier (see the ``Stream
1917 specifiers'' chapter in the ffmpeg manual) which specifies the
1918 reference stream. The default value is @code{auto}.
1920 @item segment_format @var{format}
1921 Override the inner container format, by default it is guessed by the filename
1924 @item segment_format_options @var{options_list}
1925 Set output format options using a :-separated list of key=value
1926 parameters. Values containing the @code{:} special character must be
1929 @item segment_list @var{name}
1930 Generate also a listfile named @var{name}. If not specified no
1931 listfile is generated.
1933 @item segment_list_flags @var{flags}
1934 Set flags affecting the segment list generation.
1936 It currently supports the following flags:
1939 Allow caching (only affects M3U8 list files).
1942 Allow live-friendly file generation.
1945 @item segment_list_size @var{size}
1946 Update the list file so that it contains at most @var{size}
1947 segments. If 0 the list file will contain all the segments. Default
1950 @item segment_list_entry_prefix @var{prefix}
1951 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1952 By default no prefix is applied.
1954 @item segment_list_type @var{type}
1955 Select the listing format.
1957 The following values are recognized:
1960 Generate a flat list for the created segments, one segment per line.
1963 Generate a list for the created segments, one segment per line,
1964 each line matching the format (comma-separated values):
1966 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1969 @var{segment_filename} is the name of the output file generated by the
1970 muxer according to the provided pattern. CSV escaping (according to
1971 RFC4180) is applied if required.
1973 @var{segment_start_time} and @var{segment_end_time} specify
1974 the segment start and end time expressed in seconds.
1976 A list file with the suffix @code{".csv"} or @code{".ext"} will
1977 auto-select this format.
1979 @samp{ext} is deprecated in favor or @samp{csv}.
1982 Generate an ffconcat file for the created segments. The resulting file
1983 can be read using the FFmpeg @ref{concat} demuxer.
1985 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1986 auto-select this format.
1989 Generate an extended M3U8 file, version 3, compliant with
1990 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1992 A list file with the suffix @code{".m3u8"} will auto-select this format.
1995 If not specified the type is guessed from the list file name suffix.
1997 @item segment_time @var{time}
1998 Set segment duration to @var{time}, the value must be a duration
1999 specification. Default value is "2". See also the
2000 @option{segment_times} option.
2002 Note that splitting may not be accurate, unless you force the
2003 reference stream key-frames at the given time. See the introductory
2004 notice and the examples below.
2006 @item segment_atclocktime @var{1|0}
2007 If set to "1" split at regular clock time intervals starting from 00:00
2008 o'clock. The @var{time} value specified in @option{segment_time} is
2009 used for setting the length of the splitting interval.
2011 For example with @option{segment_time} set to "900" this makes it possible
2012 to create files at 12:00 o'clock, 12:15, 12:30, etc.
2014 Default value is "0".
2016 @item segment_clocktime_offset @var{duration}
2017 Delay the segment splitting times with the specified duration when using
2018 @option{segment_atclocktime}.
2020 For example with @option{segment_time} set to "900" and
2021 @option{segment_clocktime_offset} set to "300" this makes it possible to
2022 create files at 12:05, 12:20, 12:35, etc.
2024 Default value is "0".
2026 @item segment_clocktime_wrap_duration @var{duration}
2027 Force the segmenter to only start a new segment if a packet reaches the muxer
2028 within the specified duration after the segmenting clock time. This way you
2029 can make the segmenter more resilient to backward local time jumps, such as
2030 leap seconds or transition to standard time from daylight savings time.
2032 Default is the maximum possible duration which means starting a new segment
2033 regardless of the elapsed time since the last clock time.
2035 @item segment_time_delta @var{delta}
2036 Specify the accuracy time when selecting the start time for a
2037 segment, expressed as a duration specification. Default value is "0".
2039 When delta is specified a key-frame will start a new segment if its
2040 PTS satisfies the relation:
2042 PTS >= start_time - time_delta
2045 This option is useful when splitting video content, which is always
2046 split at GOP boundaries, in case a key frame is found just before the
2047 specified split time.
2049 In particular may be used in combination with the @file{ffmpeg} option
2050 @var{force_key_frames}. The key frame times specified by
2051 @var{force_key_frames} may not be set accurately because of rounding
2052 issues, with the consequence that a key frame time may result set just
2053 before the specified time. For constant frame rate videos a value of
2054 1/(2*@var{frame_rate}) should address the worst case mismatch between
2055 the specified time and the time set by @var{force_key_frames}.
2057 @item segment_times @var{times}
2058 Specify a list of split points. @var{times} contains a list of comma
2059 separated duration specifications, in increasing order. See also
2060 the @option{segment_time} option.
2062 @item segment_frames @var{frames}
2063 Specify a list of split video frame numbers. @var{frames} contains a
2064 list of comma separated integer numbers, in increasing order.
2066 This option specifies to start a new segment whenever a reference
2067 stream key frame is found and the sequential number (starting from 0)
2068 of the frame is greater or equal to the next value in the list.
2070 @item segment_wrap @var{limit}
2071 Wrap around segment index once it reaches @var{limit}.
2073 @item segment_start_number @var{number}
2074 Set the sequence number of the first segment. Defaults to @code{0}.
2076 @item strftime @var{1|0}
2077 Use the @code{strftime} function to define the name of the new
2078 segments to write. If this is selected, the output segment name must
2079 contain a @code{strftime} function template. Default value is
2082 @item break_non_keyframes @var{1|0}
2083 If enabled, allow segments to start on frames other than keyframes. This
2084 improves behavior on some players when the time between keyframes is
2085 inconsistent, but may make things worse on others, and can cause some oddities
2086 during seeking. Defaults to @code{0}.
2088 @item reset_timestamps @var{1|0}
2089 Reset timestamps at the beginning of each segment, so that each segment
2090 will start with near-zero timestamps. It is meant to ease the playback
2091 of the generated segments. May not work with some combinations of
2092 muxers/codecs. It is set to @code{0} by default.
2094 @item initial_offset @var{offset}
2095 Specify timestamp offset to apply to the output packet timestamps. The
2096 argument must be a time duration specification, and defaults to 0.
2098 @item write_empty_segments @var{1|0}
2099 If enabled, write an empty segment if there are no packets during the period a
2100 segment would usually span. Otherwise, the segment will be filled with the next
2101 packet written. Defaults to @code{0}.
2104 Make sure to require a closed GOP when encoding and to set the GOP
2105 size to fit your segment time constraint.
2107 @subsection Examples
2111 Remux the content of file @file{in.mkv} to a list of segments
2112 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
2113 generated segments to @file{out.list}:
2115 ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
2119 Segment input and set output format options for the output segments:
2121 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
2125 Segment the input file according to the split points specified by the
2126 @var{segment_times} option:
2128 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
2132 Use the @command{ffmpeg} @option{force_key_frames}
2133 option to force key frames in the input at the specified location, together
2134 with the segment option @option{segment_time_delta} to account for
2135 possible roundings operated when setting key frame times.
2137 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
2138 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
2140 In order to force key frames on the input file, transcoding is
2144 Segment the input file by splitting the input file according to the
2145 frame numbers sequence specified with the @option{segment_frames} option:
2147 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
2151 Convert the @file{in.mkv} to TS segments using the @code{libx264}
2152 and @code{aac} encoders:
2154 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
2158 Segment the input file, and create an M3U8 live playlist (can be used
2159 as live HLS source):
2161 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
2162 -segment_list_flags +live -segment_time 10 out%03d.mkv
2166 @section smoothstreaming
2168 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
2172 Specify the number of fragments kept in the manifest. Default 0 (keep all).
2174 @item extra_window_size
2175 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
2177 @item lookahead_count
2178 Specify the number of lookahead fragments. Default 2.
2180 @item min_frag_duration
2181 Specify the minimum fragment duration (in microseconds). Default 5000000.
2183 @item remove_at_exit
2184 Specify whether to remove all fragments when finished. Default 0 (do not remove).
2191 Per stream hash testing format.
2193 This muxer computes and prints a cryptographic hash of all the input frames,
2194 on a per-stream basis. This can be used for equality checks without having
2195 to do a complete binary comparison.
2197 By default audio frames are converted to signed 16-bit raw audio and
2198 video frames to raw video before computing the hash, but the output
2199 of explicit conversions to other codecs can also be used. Timestamps
2200 are ignored. It uses the SHA-256 cryptographic hash function by default,
2201 but supports several other algorithms.
2203 The output of the muxer consists of one line per stream of the form:
2204 @var{streamindex},@var{streamtype},@var{algo}=@var{hash}, where
2205 @var{streamindex} is the index of the mapped stream, @var{streamtype} is a
2206 single character indicating the type of stream, @var{algo} is a short string
2207 representing the hash function used, and @var{hash} is a hexadecimal number
2208 representing the computed hash.
2211 @item hash @var{algorithm}
2212 Use the cryptographic hash function specified by the string @var{algorithm}.
2213 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
2214 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
2215 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
2216 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
2220 @subsection Examples
2222 To compute the SHA-256 hash of the input converted to raw audio and
2223 video, and store it in the file @file{out.sha256}:
2225 ffmpeg -i INPUT -f streamhash out.sha256
2228 To print an MD5 hash to stdout use the command:
2230 ffmpeg -i INPUT -f streamhash -hash md5 -
2233 See also the @ref{hash} and @ref{framehash} muxers.
2238 The fifo pseudo-muxer allows the separation of encoding and muxing by using
2239 first-in-first-out queue and running the actual muxer in a separate thread. This
2240 is especially useful in combination with the @ref{tee} muxer and can be used to
2241 send data to several destinations with different reliability/writing speed/latency.
2243 API users should be aware that callback functions (interrupt_callback,
2244 io_open and io_close) used within its AVFormatContext must be thread-safe.
2246 The behavior of the fifo muxer if the queue fills up or if the output fails is
2252 output can be transparently restarted with configurable delay between retries
2253 based on real time or time of the processed stream.
2256 encoding can be blocked during temporary failure, or continue transparently
2257 dropping packets in case fifo queue fills up.
2264 Specify the format name. Useful if it cannot be guessed from the
2268 Specify size of the queue (number of packets). Default value is 60.
2271 Specify format options for the underlying muxer. Muxer options can be specified
2272 as a list of @var{key}=@var{value} pairs separated by ':'.
2274 @item drop_pkts_on_overflow @var{bool}
2275 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
2276 rather than blocking the encoder. This makes it possible to continue streaming without
2277 delaying the input, at the cost of omitting part of the stream. By default
2278 this option is set to 0 (false), so in such cases the encoder will be blocked
2279 until the muxer processes some of the packets and none of them is lost.
2281 @item attempt_recovery @var{bool}
2282 If failure occurs, attempt to recover the output. This is especially useful
2283 when used with network output, since it makes it possible to restart streaming transparently.
2284 By default this option is set to 0 (false).
2286 @item max_recovery_attempts
2287 Sets maximum number of successive unsuccessful recovery attempts after which
2288 the output fails permanently. By default this option is set to 0 (unlimited).
2290 @item recovery_wait_time @var{duration}
2291 Waiting time before the next recovery attempt after previous unsuccessful
2292 recovery attempt. Default value is 5 seconds.
2294 @item recovery_wait_streamtime @var{bool}
2295 If set to 0 (false), the real time is used when waiting for the recovery
2296 attempt (i.e. the recovery will be attempted after at least
2297 recovery_wait_time seconds).
2298 If set to 1 (true), the time of the processed stream is taken into account
2299 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
2300 seconds of the stream is omitted).
2301 By default, this option is set to 0 (false).
2303 @item recover_any_error @var{bool}
2304 If set to 1 (true), recovery will be attempted regardless of type of the error
2305 causing the failure. By default this option is set to 0 (false) and in case of
2306 certain (usually permanent) errors the recovery is not attempted even when
2307 @var{attempt_recovery} is set to 1.
2309 @item restart_with_keyframe @var{bool}
2310 Specify whether to wait for the keyframe after recovering from
2311 queue overflow or failure. This option is set to 0 (false) by default.
2313 @item timeshift @var{duration}
2314 Buffer the specified amount of packets and delay writing the output. Note that
2315 @var{queue_size} must be big enough to store the packets for timeshift. At the
2316 end of the input the fifo buffer is flushed at realtime speed.
2320 @subsection Examples
2325 Stream something to rtmp server, continue processing the stream at real-time
2326 rate even in case of temporary failure (network outage) and attempt to recover
2327 streaming every second indefinitely.
2329 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
2330 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
2338 The tee muxer can be used to write the same data to several outputs, such as files or streams.
2339 It can be used, for example, to stream a video over a network and save it to disk at the same time.
2341 It is different from specifying several outputs to the @command{ffmpeg}
2342 command-line tool. With the tee muxer, the audio and video data will be encoded only once.
2343 With conventional multiple outputs, multiple encoding operations in parallel are initiated,
2344 which can be a very expensive process. The tee muxer is not useful when using the libavformat API
2345 directly because it is then possible to feed the same packets to several muxers directly.
2347 Since the tee muxer does not represent any particular output format, ffmpeg cannot auto-select
2348 output streams. So all streams intended for output must be specified using @code{-map}. See
2351 Some encoders may need different options depending on the output format;
2352 the auto-detection of this can not work with the tee muxer, so they need to be explicitly specified.
2353 The main example is the @option{global_header} flag.
2355 The slave outputs are specified in the file name given to the muxer,
2356 separated by '|'. If any of the slave name contains the '|' separator,
2357 leading or trailing spaces or any special character, those must be
2358 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
2359 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
2365 @item use_fifo @var{bool}
2366 If set to 1, slave outputs will be processed in separate threads using the @ref{fifo}
2367 muxer. This allows to compensate for different speed/latency/reliability of
2368 outputs and setup transparent recovery. By default this feature is turned off.
2371 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
2375 Muxer options can be specified for each slave by prepending them as a list of
2376 @var{key}=@var{value} pairs separated by ':', between square brackets. If
2377 the options values contain a special character or the ':' separator, they
2378 must be escaped; note that this is a second level escaping.
2380 The following special options are also recognized:
2383 Specify the format name. Required if it cannot be guessed from the
2386 @item bsfs[/@var{spec}]
2387 Specify a list of bitstream filters to apply to the specified
2390 It is possible to specify to which streams a given bitstream filter
2391 applies, by appending a stream specifier to the option separated by
2392 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
2393 stream specifiers}).
2395 If the stream specifier is not specified, the bitstream filters will be
2396 applied to all streams in the output. This will cause that output operation
2397 to fail if the output contains streams to which the bitstream filter cannot
2398 be applied e.g. @code{h264_mp4toannexb} being applied to an output containing an audio stream.
2400 Options for a bitstream filter must be specified in the form of @code{opt=value}.
2402 Several bitstream filters can be specified, separated by ",".
2404 @item use_fifo @var{bool}
2405 This allows to override tee muxer use_fifo option for individual slave muxer.
2408 This allows to override tee muxer fifo_options for individual slave muxer.
2412 Select the streams that should be mapped to the slave output,
2413 specified by a stream specifier. If not specified, this defaults to
2414 all the mapped streams. This will cause that output operation to fail
2415 if the output format does not accept all mapped streams.
2417 You may use multiple stream specifiers separated by commas (@code{,}) e.g.: @code{a:0,v}
2420 Specify behaviour on output failure. This can be set to either @code{abort} (which is
2421 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
2422 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
2423 will continue without being affected.
2426 @subsection Examples
2430 Encode something and both archive it in a WebM file and stream it
2431 as MPEG-TS over UDP:
2433 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2434 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2438 As above, but continue streaming even if output to local file fails
2439 (for example local drive fills up):
2441 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2442 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2446 Use @command{ffmpeg} to encode the input, and send the output
2447 to three different destinations. The @code{dump_extra} bitstream
2448 filter is used to add extradata information to all the output video
2449 keyframes packets, as requested by the MPEG-TS format. The select
2450 option is applied to @file{out.aac} in order to make it contain only
2453 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2454 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
2458 As above, but select only stream @code{a:1} for the audio output. Note
2459 that a second level escaping must be performed, as ":" is a special
2460 character used to separate options.
2462 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2463 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
2467 @section webm_dash_manifest
2469 WebM DASH Manifest muxer.
2471 This muxer implements the WebM DASH Manifest specification to generate the DASH
2472 manifest XML. It also supports manifest generation for DASH live streams.
2474 For more information see:
2478 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
2480 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
2485 This muxer supports the following options:
2488 @item adaptation_sets
2489 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
2490 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
2491 audio and video streams. Any number of adaptation sets can be added using this option.
2494 Set this to 1 to create a live stream DASH Manifest. Default: 0.
2496 @item chunk_start_index
2497 Start index of the first chunk. This will go in the @samp{startNumber} attribute
2498 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
2500 @item chunk_duration_ms
2501 Duration of each chunk in milliseconds. This will go in the @samp{duration}
2502 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
2504 @item utc_timing_url
2505 URL of the page that will return the UTC timestamp in ISO format. This will go
2506 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
2509 @item time_shift_buffer_depth
2510 Smallest time (in seconds) shifting buffer for which any Representation is
2511 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
2512 attribute of the @samp{MPD} element. Default: 60.
2514 @item minimum_update_period
2515 Minimum update period (in seconds) of the manifest. This will go in the
2516 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
2522 ffmpeg -f webm_dash_manifest -i video1.webm \
2523 -f webm_dash_manifest -i video2.webm \
2524 -f webm_dash_manifest -i audio1.webm \
2525 -f webm_dash_manifest -i audio2.webm \
2526 -map 0 -map 1 -map 2 -map 3 \
2528 -f webm_dash_manifest \
2529 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
2535 WebM Live Chunk Muxer.
2537 This muxer writes out WebM headers and chunks as separate files which can be
2538 consumed by clients that support WebM Live streams via DASH.
2542 This muxer supports the following options:
2545 @item chunk_start_index
2546 Index of the first chunk (defaults to 0).
2549 Filename of the header where the initialization data will be written.
2551 @item audio_chunk_duration
2552 Duration of each audio chunk in milliseconds (defaults to 5000).
2557 ffmpeg -f v4l2 -i /dev/video0 \
2561 -s 640x360 -keyint_min 30 -g 30 \
2563 -header webm_live_video_360.hdr \
2564 -chunk_start_index 1 \
2565 webm_live_video_360_%d.chk \
2570 -header webm_live_audio_128.hdr \
2571 -chunk_start_index 1 \
2572 -audio_chunk_duration 1000 \
2573 webm_live_audio_128_%d.chk