4 Muxers are configured elements in FFmpeg which allow writing
5 multimedia streams to a particular type of file.
7 When you configure your FFmpeg build, all the supported muxers
8 are enabled by default. You can list all available muxers using the
9 configure option @code{--list-muxers}.
11 You can disable all the muxers with the configure option
12 @code{--disable-muxers} and selectively enable / disable single muxers
13 with the options @code{--enable-muxer=@var{MUXER}} /
14 @code{--disable-muxer=@var{MUXER}}.
16 The option @code{-muxers} of the ff* tools will display the list of
17 enabled muxers. Use @code{-formats} to view a combined list of
18 enabled demuxers and muxers.
20 A description of some of the currently available muxers follows.
25 Audio Interchange File Format muxer.
29 It accepts the following options:
33 Enable ID3v2 tags writing when set to 1. Default is 0 (disabled).
36 Select ID3v2 version to write. Currently only version 3 and 4 (aka.
37 ID3v2.3 and ID3v2.4) are supported. The default is version 4.
44 Advanced Systems Format muxer.
46 Note that Windows Media Audio (wma) and Windows Media Video (wmv) use this
51 It accepts the following options:
55 Set the muxer packet size. By tuning this setting you may reduce data
56 fragmentation or muxer overhead depending on your source. Default value is
57 3200, minimum is 100, maximum is 64k.
64 Audio Video Interleaved muxer.
68 It accepts the following options:
71 @item reserve_index_space
72 Reserve the specified amount of bytes for the OpenDML master index of each
73 stream within the file header. By default additional master indexes are
74 embedded within the data packets if there is no space left in the first master
75 index and are linked together as a chain of indexes. This index structure can
76 cause problems for some use cases, e.g. third-party software strictly relying
77 on the OpenDML index specification or when file seeking is slow. Reserving
78 enough index space in the file header avoids these problems.
80 The required index space depends on the output file size and should be about 16
81 bytes per gigabyte. When this option is omitted or set to zero the necessary
82 index space is guessed.
84 @item write_channel_mask
85 Write the channel layout mask into the audio stream header.
87 This option is enabled by default. Disabling the channel mask can be useful in
88 specific scenarios, e.g. when merging multiple audio streams into one for
89 compatibility with software that only supports a single audio stream in AVI
90 (see @ref{amerge,,the "amerge" section in the ffmpeg-filters manual,ffmpeg-filters}).
97 Chromaprint fingerprinter.
99 This muxer feeds audio data to the Chromaprint library,
100 which generates a fingerprint for the provided audio data. See @url{https://acoustid.org/chromaprint}
102 It takes a single signed native-endian 16-bit raw audio stream of at most 2 channels.
107 @item silence_threshold
108 Threshold for detecting silence. Range is from -1 to 32767, where -1 disables
109 silence detection. Silence detection can only be used with version 3 of the
111 Silence detection must be disabled for use with the AcoustID service. Default is -1.
114 Version of algorithm to fingerprint with. Range is 0 to 4.
115 Version 3 enables silence detection. Default is 1.
118 Format to output the fingerprint as. Accepts the following options:
121 Binary raw fingerprint
124 Binary compressed fingerprint
127 Base64 compressed fingerprint @emph{(default)}
136 CRC (Cyclic Redundancy Check) testing format.
138 This muxer computes and prints the Adler-32 CRC of all the input audio
139 and video frames. By default audio frames are converted to signed
140 16-bit raw audio and video frames to raw video before computing the
143 The output of the muxer consists of a single line of the form:
144 CRC=0x@var{CRC}, where @var{CRC} is a hexadecimal number 0-padded to
145 8 digits containing the CRC for all the decoded input frames.
147 See also the @ref{framecrc} muxer.
151 For example to compute the CRC of the input, and store it in the file
154 ffmpeg -i INPUT -f crc out.crc
157 You can print the CRC to stdout with the command:
159 ffmpeg -i INPUT -f crc -
162 You can select the output format of each frame with @command{ffmpeg} by
163 specifying the audio and video codec and format. For example to
164 compute the CRC of the input audio converted to PCM unsigned 8-bit
165 and the input video converted to MPEG-2 video, use the command:
167 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f crc -
172 Adobe Flash Video Format muxer.
174 This muxer accepts the following options:
178 @item flvflags @var{flags}
183 @item aac_seq_header_detect
184 Place AAC sequence header based on audio stream data.
186 @item no_sequence_end
187 Disable sequence end tag.
190 Disable metadata tag.
192 @item no_duration_filesize
193 Disable duration and filesize in metadata when they are equal to zero
194 at the end of stream. (Be used to non-seekable living stream).
196 @item add_keyframe_index
197 Used to facilitate seeking; particularly for HTTP pseudo streaming.
204 Dynamic Adaptive Streaming over HTTP (DASH) muxer that creates segments
205 and manifest files according to the MPEG-DASH standard ISO/IEC 23009-1:2014.
207 For more information see:
211 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
213 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
216 It creates a MPD manifest file and segment files for each stream.
218 The segment filename might contain pre-defined identifiers used with SegmentTemplate
219 as defined in section 5.3.9.4.4 of the standard. Available identifiers are "$RepresentationID$",
220 "$Number$", "$Bandwidth$" and "$Time$".
221 In addition to the standard identifiers, an ffmpeg-specific "$ext$" identifier is also supported.
222 When specified ffmpeg will replace $ext$ in the file name with muxing format's extensions such as mp4, webm etc.,
225 ffmpeg -re -i <input> -map 0 -map 0 -c:a libfdk_aac -c:v libx264 \
226 -b:v:0 800k -b:v:1 300k -s:v:1 320x170 -profile:v:1 baseline \
227 -profile:v:0 main -bf 1 -keyint_min 120 -g 120 -sc_threshold 0 \
228 -b_strategy 0 -ar:a:1 22050 -use_timeline 1 -use_template 1 \
229 -window_size 5 -adaptation_sets "id=0,streams=v id=1,streams=a" \
230 -f dash /path/to/out.mpd
234 @item min_seg_duration @var{microseconds}
235 This is a deprecated option to set the segment length in microseconds, use @var{seg_duration} instead.
236 @item seg_duration @var{duration}
237 Set the segment length in seconds (fractional value can be set). The value is
238 treated as average segment duration when @var{use_template} is enabled and
239 @item frag_duration @var{duration}
240 Set the length in seconds of fragments within segments (fractional value can be set).
241 @item frag_type @var{type}
242 Set the type of interval for fragmentation.
243 @item window_size @var{size}
244 Set the maximum number of segments kept in the manifest.
245 @item extra_window_size @var{size}
246 Set the maximum number of segments kept outside of the manifest before removing from disk.
247 @item remove_at_exit @var{remove}
248 Enable (1) or disable (0) removal of all segments when finished.
249 @item use_template @var{template}
250 Enable (1) or disable (0) use of SegmentTemplate instead of SegmentList.
251 @item use_timeline @var{timeline}
252 Enable (1) or disable (0) use of SegmentTimeline in SegmentTemplate.
253 @item single_file @var{single_file}
254 Enable (1) or disable (0) storing all segments in one file, accessed using byte ranges.
255 @item single_file_name @var{file_name}
256 DASH-templated name to be used for baseURL. Implies @var{single_file} set to "1". In the template, "$ext$" is replaced with the file name extension specific for the segment format.
257 @item init_seg_name @var{init_name}
258 DASH-templated name to used for the initialization segment. Default is "init-stream$RepresentationID$.$ext$". "$ext$" is replaced with the file name extension specific for the segment format.
259 @item media_seg_name @var{segment_name}
260 DASH-templated name to used for the media segments. Default is "chunk-stream$RepresentationID$-$Number%05d$.$ext$". "$ext$" is replaced with the file name extension specific for the segment format.
261 @item utc_timing_url @var{utc_url}
262 URL of the page that will return the UTC timestamp in ISO format. Example: "https://time.akamai.com/?iso"
263 @item method @var{method}
264 Use the given HTTP method to create output files. Generally set to PUT or POST.
265 @item http_user_agent @var{user_agent}
266 Override User-Agent field in HTTP header. Applicable only for HTTP output.
267 @item http_persistent @var{http_persistent}
268 Use persistent HTTP connections. Applicable only for HTTP output.
269 @item hls_playlist @var{hls_playlist}
270 Generate HLS playlist files as well. The master playlist is generated with the filename master.m3u8.
271 One media playlist file is generated for each stream with filenames media_0.m3u8, media_1.m3u8, etc.
272 @item streaming @var{streaming}
273 Enable (1) or disable (0) chunk streaming mode of output. In chunk streaming
274 mode, each frame will be a moof fragment which forms a chunk.
275 @item adaptation_sets @var{adaptation_sets}
276 Assign streams to AdaptationSets. Syntax is "id=x,streams=a,b,c id=y,streams=d,e" with x and y being the IDs
277 of the adaptation sets and a,b,c,d and e are the indices of the mapped streams.
279 To map all video (or audio) streams to an AdaptationSet, "v" (or "a") can be used as stream identifier instead of IDs.
281 When no assignment is defined, this defaults to an AdaptationSet for each stream.
283 Optional syntax is "id=x,seg_duration=x,frag_duration=x,frag_type=type,descriptor=descriptor_string,streams=a,b,c id=y,seg_duration=y,frag_type=type,streams=d,e" and so on,
284 descriptor is useful to the scheme defined by ISO/IEC 23009-1:2014/Amd.2:2015.
285 For example, -adaptation_sets "id=0,descriptor=<SupplementalProperty schemeIdUri=\"urn:mpeg:dash:srd:2014\" value=\"0,0,0,1,1,2,2\"/>,streams=v".
286 Please note that descriptor string should be a self-closing xml tag.
287 seg_duration, frag_duration and frag_type override the global option values for each adaptation set.
288 For example, -adaptation_sets "id=0,seg_duration=2,frag_duration=1,frag_type=duration,streams=v id=1,seg_duration=2,frag_type=none,streams=a"
289 type_id marks an adaptation set as containing streams meant to be used for Trick Mode for the referenced adaptation set.
290 For example, -adaptation_sets "id=0,seg_duration=2,frag_type=none,streams=0 id=1,seg_duration=10,frag_type=none,trick_id=0,streams=1"
291 @item timeout @var{timeout}
292 Set timeout for socket I/O operations. Applicable only for HTTP output.
293 @item index_correction @var{index_correction}
294 Enable (1) or Disable (0) segment index correction logic. Applicable only when
295 @var{use_template} is enabled and @var{use_timeline} is disabled.
297 When enabled, the logic monitors the flow of segment indexes. If a streams's
298 segment index value is not at the expected real time position, then the logic
299 corrects that index value.
301 Typically this logic is needed in live streaming use cases. The network bandwidth
302 fluctuations are common during long run streaming. Each fluctuation can cause
303 the segment indexes fall behind the expected real time position.
304 @item format_options @var{options_list}
305 Set container format (mp4/webm) options using a @code{:} separated list of
306 key=value parameters. Values containing @code{:} special characters must be
309 @item global_sidx @var{global_sidx}
310 Write global SIDX atom. Applicable only for single file, mp4 output, non-streaming mode.
312 @item dash_segment_type @var{dash_segment_type}
316 If this flag is set, the dash segment files format will be selected based on the stream codec. This is the default mode.
319 If this flag is set, the dash segment files will be in in ISOBMFF format.
322 If this flag is set, the dash segment files will be in in WebM format.
325 @item ignore_io_errors @var{ignore_io_errors}
326 Ignore IO errors during open and write. Useful for long-duration runs with network output.
328 @item lhls @var{lhls}
329 Enable Low-latency HLS(LHLS). Adds #EXT-X-PREFETCH tag with current segment's URI.
330 Apple doesn't have an official spec for LHLS. Meanwhile hls.js player folks are
331 trying to standardize a open LHLS spec. The draft spec is available in https://github.com/video-dev/hlsjs-rfcs/blob/lhls-spec/proposals/0001-lhls.md
332 This option will also try to comply with the above open spec, till Apple's spec officially supports it.
333 Applicable only when @var{streaming} and @var{hls_playlist} options are enabled.
334 This is an experimental feature.
336 @item ldash @var{ldash}
337 Enable Low-latency Dash by constraining the presence and values of some elements.
339 @item master_m3u8_publish_rate @var{master_m3u8_publish_rate}
340 Publish master playlist repeatedly every after specified number of segment intervals.
342 @item write_prft @var{write_prft}
343 Write Producer Reference Time elements on supported streams. This also enables writing
344 prft boxes in the underlying muxer. Applicable only when the @var{utc_url} option is enabled.
345 It's set to auto by default, in which case the muxer will attempt to enable it only in modes
348 @item mpd_profile @var{mpd_profile}
349 Set one or more manifest profiles.
351 @item http_opts @var{http_opts}
352 A :-separated list of key=value options to pass to the underlying HTTP
353 protocol. Applicable only for HTTP output.
355 @item target_latency @var{target_latency}
356 Set an intended target latency in seconds (fractional value can be set) for serving. Applicable only when @var{streaming} and @var{write_prft} options are enabled.
357 This is an informative fields clients can use to measure the latency of the service.
359 @item min_playback_rate @var{min_playback_rate}
360 Set the minimum playback rate indicated as appropriate for the purposes of automatically
361 adjusting playback latency and buffer occupancy during normal playback by clients.
363 @item max_playback_rate @var{max_playback_rate}
364 Set the maximum playback rate indicated as appropriate for the purposes of automatically
365 adjusting playback latency and buffer occupancy during normal playback by clients.
372 Per-packet CRC (Cyclic Redundancy Check) testing format.
374 This muxer computes and prints the Adler-32 CRC for each audio
375 and video packet. By default audio frames are converted to signed
376 16-bit raw audio and video frames to raw video before computing the
379 The output of the muxer consists of a line for each audio and video
382 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
385 @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
390 For example to compute the CRC of the audio and video frames in
391 @file{INPUT}, converted to raw audio and video packets, and store it
392 in the file @file{out.crc}:
394 ffmpeg -i INPUT -f framecrc out.crc
397 To print the information to stdout, use the command:
399 ffmpeg -i INPUT -f framecrc -
402 With @command{ffmpeg}, you can select the output format to which the
403 audio and video frames are encoded before computing the CRC for each
404 packet by specifying the audio and video codec. For example, to
405 compute the CRC of each decoded input audio frame converted to PCM
406 unsigned 8-bit and of each decoded input video frame converted to
407 MPEG-2 video, use the command:
409 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
412 See also the @ref{crc} muxer.
417 Per-packet hash testing format.
419 This muxer computes and prints a cryptographic hash for each audio
420 and video packet. This can be used for packet-by-packet equality
421 checks without having to individually do a binary comparison on each.
423 By default audio frames are converted to signed 16-bit raw audio and
424 video frames to raw video before computing the hash, but the output
425 of explicit conversions to other codecs can also be used. It uses the
426 SHA-256 cryptographic hash function by default, but supports several
429 The output of the muxer consists of a line for each audio and video
432 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
435 @var{hash} is a hexadecimal number representing the computed hash
439 @item hash @var{algorithm}
440 Use the cryptographic hash function specified by the string @var{algorithm}.
441 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
442 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
443 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
444 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
450 To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
451 converted to raw audio and video packets, and store it in the file
454 ffmpeg -i INPUT -f framehash out.sha256
457 To print the information to stdout, using the MD5 hash function, use
460 ffmpeg -i INPUT -f framehash -hash md5 -
463 See also the @ref{hash} muxer.
468 Per-packet MD5 testing format.
470 This is a variant of the @ref{framehash} muxer. Unlike that muxer,
471 it defaults to using the MD5 hash function.
475 To compute the MD5 hash of the audio and video frames in @file{INPUT},
476 converted to raw audio and video packets, and store it in the file
479 ffmpeg -i INPUT -f framemd5 out.md5
482 To print the information to stdout, use the command:
484 ffmpeg -i INPUT -f framemd5 -
487 See also the @ref{framehash} and @ref{md5} muxers.
494 It accepts the following options:
498 Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
499 for looping indefinitely (default).
502 Force the delay (expressed in centiseconds) after the last frame. Each frame
503 ends with a delay until the next frame. The default is @code{-1}, which is a
504 special value to tell the muxer to re-use the previous delay. In case of a
505 loop, you might want to customize this value to mark a pause for instance.
508 For example, to encode a gif looping 10 times, with a 5 seconds delay between
511 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
514 Note 1: if you wish to extract the frames into separate GIF files, you need to
515 force the @ref{image2} muxer:
517 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
520 Note 2: the GIF format has a very large time base: the delay between two frames
521 can therefore not be smaller than one centi second.
528 This muxer computes and prints a cryptographic hash of all the input
529 audio and video frames. This can be used for equality checks without
530 having to do a complete binary comparison.
532 By default audio frames are converted to signed 16-bit raw audio and
533 video frames to raw video before computing the hash, but the output
534 of explicit conversions to other codecs can also be used. Timestamps
535 are ignored. It uses the SHA-256 cryptographic hash function by default,
536 but supports several other algorithms.
538 The output of the muxer consists of a single line of the form:
539 @var{algo}=@var{hash}, where @var{algo} is a short string representing
540 the hash function used, and @var{hash} is a hexadecimal number
541 representing the computed hash.
544 @item hash @var{algorithm}
545 Use the cryptographic hash function specified by the string @var{algorithm}.
546 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
547 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
548 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
549 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
555 To compute the SHA-256 hash of the input converted to raw audio and
556 video, and store it in the file @file{out.sha256}:
558 ffmpeg -i INPUT -f hash out.sha256
561 To print an MD5 hash to stdout use the command:
563 ffmpeg -i INPUT -f hash -hash md5 -
566 See also the @ref{framehash} muxer.
571 Apple HTTP Live Streaming muxer that segments MPEG-TS according to
572 the HTTP Live Streaming (HLS) specification.
574 It creates a playlist file, and one or more segment files. The output filename
575 specifies the playlist filename.
577 By default, the muxer creates a file for each segment produced. These files
578 have the same name as the playlist, followed by a sequential number and a
581 Make sure to require a closed GOP when encoding and to set the GOP
582 size to fit your segment time constraint.
584 For example, to convert an input file with @command{ffmpeg}:
586 ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
588 This example will produce the playlist, @file{out.m3u8}, and segment files:
589 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
591 See also the @ref{segment} muxer, which provides a more generic and
592 flexible implementation of a segmenter, and can be used to perform HLS
597 This muxer supports the following options:
600 @item hls_init_time @var{seconds}
601 Set the initial target segment length in seconds. Default value is @var{0}.
602 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
603 After the initial playlist is filled @command{ffmpeg} will cut segments
604 at duration equal to @code{hls_time}
606 @item hls_time @var{seconds}
607 Set the target segment length in seconds. Default value is 2.
608 Segment will be cut on the next key frame after this time has passed.
610 @item hls_list_size @var{size}
611 Set the maximum number of playlist entries. If set to 0 the list file
612 will contain all the segments. Default value is 5.
614 @item hls_delete_threshold @var{size}
615 Set the number of unreferenced segments to keep on disk before @code{hls_flags delete_segments}
616 deletes them. Increase this to allow continue clients to download segments which
617 were recently referenced in the playlist. Default value is 1, meaning segments older than
618 @code{hls_list_size+1} will be deleted.
620 @item hls_ts_options @var{options_list}
621 Set output format options using a :-separated list of key=value
622 parameters. Values containing @code{:} special characters must be
625 @item hls_wrap @var{wrap}
626 This is a deprecated option, you can use @code{hls_list_size}
627 and @code{hls_flags delete_segments} instead it
629 This option is useful to avoid to fill the disk with many segment
630 files, and limits the maximum number of segment files written to disk
634 @item hls_start_number_source
635 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
636 Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
637 segment and subtitle filenames. In any case, if @code{hls_flags append_list}
638 is set and read playlist sequence number is greater than the specified start sequence number,
639 then that value will be used as start value.
641 It accepts the following values:
645 @item generic (default)
646 Set the starting sequence numbers according to @var{start_number} option value.
649 The start number will be the seconds since epoch (1970-01-01 00:00:00)
652 The start number will be the microseconds since epoch (1970-01-01 00:00:00)
655 The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
659 @item start_number @var{number}
660 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
661 when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
662 Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
665 @item hls_allow_cache @var{allowcache}
666 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
668 @item hls_base_url @var{baseurl}
669 Append @var{baseurl} to every entry in the playlist.
670 Useful to generate playlists with absolute paths.
672 Note that the playlist sequence number must be unique for each segment
673 and it is not to be confused with the segment filename sequence number
674 which can be cyclic, for example if the @option{wrap} option is
677 @item hls_segment_filename @var{filename}
678 Set the segment filename. Unless @code{hls_flags single_file} is set,
679 @var{filename} is used as a string format with the segment number:
681 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
683 This example will produce the playlist, @file{out.m3u8}, and segment files:
684 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
686 @var{filename} may contain full path or relative path specification,
687 but only the file name part without any path info will be contained in the m3u8 segment list.
688 Should a relative path be specified, the path of the created segment
689 files will be relative to the current working directory.
690 When strftime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
692 When @code{var_stream_map} is set with two or more variant streams, the
693 @var{filename} pattern must contain the string "%v", this string specifies
694 the position of variant stream index in the generated segment file names.
696 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
697 -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" \
698 -hls_segment_filename 'file_%v_%03d.ts' out_%v.m3u8
700 This example will produce the playlists segment file sets:
701 @file{file_0_000.ts}, @file{file_0_001.ts}, @file{file_0_002.ts}, etc. and
702 @file{file_1_000.ts}, @file{file_1_001.ts}, @file{file_1_002.ts}, etc.
704 The string "%v" may be present in the filename or in the last directory name
705 containing the file, but only in one of them. (Additionally, %v may appear multiple times in the last
706 sub-directory or filename.) If the string %v is present in the directory name, then
707 sub-directories are created after expanding the directory name pattern. This
708 enables creation of segments corresponding to different variant streams in
711 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
712 -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" \
713 -hls_segment_filename 'vs%v/file_%03d.ts' vs%v/out.m3u8
715 This example will produce the playlists segment file sets:
716 @file{vs0/file_000.ts}, @file{vs0/file_001.ts}, @file{vs0/file_002.ts}, etc. and
717 @file{vs1/file_000.ts}, @file{vs1/file_001.ts}, @file{vs1/file_002.ts}, etc.
720 Same as strftime option, will be deprecated.
723 Use strftime() on @var{filename} to expand the segment filename with localtime.
724 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
725 hls_flag and %%d will be the specifier.
727 ffmpeg -i in.nut -strftime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
729 This example will produce the playlist, @file{out.m3u8}, and segment files:
730 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
731 Note: On some systems/environments, the @code{%s} specifier is not available. See
732 @code{strftime()} documentation.
734 ffmpeg -i in.nut -strftime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
736 This example will produce the playlist, @file{out.m3u8}, and segment files:
737 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
739 @item use_localtime_mkdir
740 Same as strftime_mkdir option, will be deprecated .
743 Used together with -strftime_mkdir, it will create all subdirectories which
744 is expanded in @var{filename}.
746 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y%m%d/file-%Y%m%d-%s.ts' out.m3u8
748 This example will create a directory 201560215 (if it does not exist), and then
749 produce the playlist, @file{out.m3u8}, and segment files:
750 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
753 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y/%m/%d/file-%Y%m%d-%s.ts' out.m3u8
755 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
756 produce the playlist, @file{out.m3u8}, and segment files:
757 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
760 @item hls_key_info_file @var{key_info_file}
761 Use the information in @var{key_info_file} for segment encryption. The first
762 line of @var{key_info_file} specifies the key URI written to the playlist. The
763 key URL is used to access the encryption key during playback. The second line
764 specifies the path to the key file used to obtain the key during the encryption
765 process. The key file is read as a single packed array of 16 octets in binary
766 format. The optional third line specifies the initialization vector (IV) as a
767 hexadecimal string to be used instead of the segment sequence number (default)
768 for encryption. Changes to @var{key_info_file} will result in segment
769 encryption with the new key/IV and an entry in the playlist for the new key
770 URI/IV if @code{hls_flags periodic_rekey} is enabled.
772 Key info file format:
781 http://server/file.key
786 Example key file paths:
794 0123456789ABCDEF0123456789ABCDEF
797 Key info file example:
799 http://server/file.key
801 0123456789ABCDEF0123456789ABCDEF
804 Example shell script:
808 openssl rand 16 > file.key
809 echo $BASE_URL/file.key > file.keyinfo
810 echo file.key >> file.keyinfo
811 echo $(openssl rand -hex 16) >> file.keyinfo
812 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
813 -hls_key_info_file file.keyinfo out.m3u8
816 @item -hls_enc @var{enc}
817 Enable (1) or disable (0) the AES128 encryption.
818 When enabled every segment generated is encrypted and the encryption key
819 is saved as @var{playlist name}.key.
821 @item -hls_enc_key @var{key}
822 Hex-coded 16byte key to encrypt the segments, by default it
823 is randomly generated.
825 @item -hls_enc_key_url @var{keyurl}
826 If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
829 @item -hls_enc_iv @var{iv}
830 Hex-coded 16byte initialization vector for every segment instead
831 of the autogenerated ones.
833 @item hls_segment_type @var{flags}
838 Output segment files in MPEG-2 Transport Stream format. This is
839 compatible with all HLS versions.
842 Output segment files in fragmented MP4 format, similar to MPEG-DASH.
843 fmp4 files may be used in HLS version 7 and above.
847 @item hls_fmp4_init_filename @var{filename}
848 Set filename to the fragment files header file, default filename is @file{init.mp4}.
850 @item hls_fmp4_init_resend @var{filename}
851 Resend init file after m3u8 file refresh every time, default is @var{0}.
853 When @code{var_stream_map} is set with two or more variant streams, the
854 @var{filename} pattern must contain the string "%v", this string specifies
855 the position of variant stream index in the generated init file names.
856 The string "%v" may be present in the filename or in the last directory name
857 containing the file. If the string is present in the directory name, then
858 sub-directories are created after expanding the directory name pattern. This
859 enables creation of init files corresponding to different variant streams in
862 @item hls_flags @var{flags}
867 If this flag is set, the muxer will store all segments in a single MPEG-TS
868 file, and will use byte ranges in the playlist. HLS playlists generated with
869 this way will have the version number 4.
872 ffmpeg -i in.nut -hls_flags single_file out.m3u8
874 Will produce the playlist, @file{out.m3u8}, and a single segment file,
877 @item delete_segments
878 Segment files removed from the playlist are deleted after a period of time
879 equal to the duration of the segment plus the duration of the playlist.
882 Append new segments into the end of old segment list,
883 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
885 @item round_durations
886 Round the duration info in the playlist file segment info to integer
887 values, instead of using floating point.
890 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
891 first segment's information.
894 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
897 The file specified by @code{hls_key_info_file} will be checked periodically and
898 detect updates to the encryption info. Be sure to replace this file atomically,
899 including the file containing the AES encryption key.
901 @item independent_segments
902 Add the @code{#EXT-X-INDEPENDENT-SEGMENTS} to playlists that has video segments
903 and when all the segments of that playlist are guaranteed to start with a Key frame.
906 Add the @code{#EXT-X-I-FRAMES-ONLY} to playlists that has video segments
907 and can play only I-frames in the @code{#EXT-X-BYTERANGE} mode.
910 Allow segments to start on frames other than keyframes. This improves
911 behavior on some players when the time between keyframes is inconsistent,
912 but may make things worse on others, and can cause some oddities during
913 seeking. This flag should be used with the @code{hls_time} option.
915 @item program_date_time
916 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
918 @item second_level_segment_index
919 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
920 besides date/time values when strftime is on.
921 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
923 @item second_level_segment_size
924 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
925 expression besides date/time values when strftime is on.
926 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
928 @item second_level_segment_duration
929 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
930 expression besides date/time values when strftime is on.
931 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
934 ffmpeg -i sample.mpeg \
935 -f hls -hls_time 3 -hls_list_size 5 \
936 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
937 -strftime 1 -strftime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
939 This will produce segments like this:
940 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
943 Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
944 serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
945 before they have been added to the m3u8 playlist. This flag also affects how m3u8 playlist files are created.
946 If this flag is set, all playlist files will written into temporary file and renamed after they are complete, similarly as segments are handled.
947 But playlists with @code{file} protocol and with type (@code{hls_playlist_type}) other than @code{vod}
948 are always written into temporary file regardless of this flag. Master playlist files (@code{master_pl_name}), if any, with @code{file} protocol,
949 are always written into temporary file regardless of this flag if @code{master_pl_publish_rate} value is other than zero.
953 @item hls_playlist_type event
954 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
955 @option{hls_list_size} to 0; the playlist can only be appended to.
957 @item hls_playlist_type vod
958 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
959 @option{hls_list_size} to 0; the playlist must not change.
962 Use the given HTTP method to create the hls files.
964 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
966 This example will upload all the mpegts segment files to the HTTP
967 server using the HTTP PUT method, and update the m3u8 files every
968 @code{refresh} times using the same method.
969 Note that the HTTP server must support the given method for uploading
972 @item http_user_agent
973 Override User-Agent field in HTTP header. Applicable only for HTTP output.
976 Map string which specifies how to group the audio, video and subtitle streams
977 into different variant streams. The variant stream groups are separated
979 Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
980 the keys to specify audio, video and subtitle streams respectively.
981 Allowed values are 0 to 9 (limited just based on practical usage).
983 When there are two or more variant streams, the output filename pattern must
984 contain the string "%v", this string specifies the position of variant stream
985 index in the output media playlist filenames. The string "%v" may be present in
986 the filename or in the last directory name containing the file. If the string is
987 present in the directory name, then sub-directories are created after expanding
988 the directory name pattern. This enables creation of variant streams in
992 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
993 -map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0 v:1,a:1" \
994 http://example.com/live/out_%v.m3u8
996 This example creates two hls variant streams. The first variant stream will
997 contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
998 second variant stream will contain video stream of bitrate 256k and audio
999 stream of bitrate 32k. Here, two media playlist with file names out_0.m3u8 and
1000 out_1.m3u8 will be created. If you want something meaningful text instead of indexes
1001 in result names, you may specify names for each or some of the variants
1002 as in the following example.
1006 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1007 -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" \
1008 http://example.com/live/out_%v.m3u8
1011 This example creates two hls variant streams as in the previous one.
1012 But here, the two media playlist with file names out_my_hd.m3u8 and
1013 out_my_sd.m3u8 will be created.
1016 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
1017 -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
1018 http://example.com/live/out_%v.m3u8
1020 This example creates three hls variant streams. The first variant stream will
1021 be a video only stream with video bitrate 1000k, the second variant stream will
1022 be an audio only stream with bitrate 64k and the third variant stream will be a
1023 video only stream with bitrate 256k. Here, three media playlist with file names
1024 out_0.m3u8, out_1.m3u8 and out_2.m3u8 will be created.
1026 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1027 -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" \
1028 http://example.com/live/vs_%v/out.m3u8
1030 This example creates the variant streams in subdirectories. Here, the first
1031 media playlist is created at @file{http://example.com/live/vs_0/out.m3u8} and
1032 the second one at @file{http://example.com/live/vs_1/out.m3u8}.
1034 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k \
1035 -map 0:a -map 0:a -map 0:v -map 0:v -f hls \
1036 -var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
1037 -master_pl_name master.m3u8 \
1038 http://example.com/live/out_%v.m3u8
1040 This example creates two audio only and two video only variant streams. In
1041 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1042 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1043 and they are mapped to the two video only variant streams with audio group names
1044 'aud_low' and 'aud_high'.
1046 By default, a single hls variant containing all the encoded streams is created.
1049 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
1050 -map 0:a -map 0:a -map 0:v -f hls \
1051 -var_stream_map "a:0,agroup:aud_low,default:yes a:1,agroup:aud_low v:0,agroup:aud_low" \
1052 -master_pl_name master.m3u8 \
1053 http://example.com/live/out_%v.m3u8
1055 This example creates two audio only and one video only variant streams. In
1056 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1057 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1058 and they are mapped to the one video only variant streams with audio group name
1059 'aud_low', and the audio group have default stat is NO or YES.
1061 By default, a single hls variant containing all the encoded streams is created.
1064 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
1065 -map 0:a -map 0:a -map 0:v -f hls \
1066 -var_stream_map "a:0,agroup:aud_low,default:yes,language:ENG a:1,agroup:aud_low,language:CHN v:0,agroup:aud_low" \
1067 -master_pl_name master.m3u8 \
1068 http://example.com/live/out_%v.m3u8
1070 This example creates two audio only and one video only variant streams. In
1071 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1072 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1073 and they are mapped to the one video only variant streams with audio group name
1074 'aud_low', and the audio group have default stat is NO or YES, and one audio
1075 have and language is named ENG, the other audio language is named CHN.
1077 By default, a single hls variant containing all the encoded streams is created.
1080 ffmpeg -y -i input_with_subtitle.mkv \
1081 -b:v:0 5250k -c:v h264 -pix_fmt yuv420p -profile:v main -level 4.1 \
1083 -c:s webvtt -c:a mp2 -ar 48000 -ac 2 -map 0:v -map 0:a:0 -map 0:s:0 \
1084 -f hls -var_stream_map "v:0,a:0,s:0,sgroup:subtitle" \
1085 -master_pl_name master.m3u8 -t 300 -hls_time 10 -hls_init_time 4 -hls_list_size \
1086 10 -master_pl_publish_rate 10 -hls_flags \
1087 delete_segments+discont_start+split_by_time ./tmp/video.m3u8
1090 This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=SUBTITLES} in
1091 the master playlist with webvtt subtitle group name 'subtitle'. Please make sure
1092 the input file has one text subtitle stream at least.
1095 Map string which specifies different closed captions groups and their
1096 attributes. The closed captions stream groups are separated by space.
1097 Expected string format is like this
1098 "ccgroup:<group name>,instreamid:<INSTREAM-ID>,language:<language code> ....".
1099 'ccgroup' and 'instreamid' are mandatory attributes. 'language' is an optional
1101 The closed captions groups configured using this option are mapped to different
1102 variant streams by providing the same 'ccgroup' name in the
1103 @code{var_stream_map} string. If @code{var_stream_map} is not set, then the
1104 first available ccgroup in @code{cc_stream_map} is mapped to the output variant
1105 stream. The examples for these two use cases are given below.
1108 ffmpeg -re -i in.ts -b:v 1000k -b:a 64k -a53cc 1 -f hls \
1109 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en" \
1110 -master_pl_name master.m3u8 \
1111 http://example.com/live/out.m3u8
1113 This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=CLOSED-CAPTIONS} in
1114 the master playlist with group name 'cc', language 'en' (english) and
1115 INSTREAM-ID 'CC1'. Also, it adds @code{CLOSED-CAPTIONS} attribute with group
1116 name 'cc' for the output variant stream.
1118 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1119 -a53cc:0 1 -a53cc:1 1\
1120 -map 0:v -map 0:a -map 0:v -map 0:a -f hls \
1121 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en ccgroup:cc,instreamid:CC2,language:sp" \
1122 -var_stream_map "v:0,a:0,ccgroup:cc v:1,a:1,ccgroup:cc" \
1123 -master_pl_name master.m3u8 \
1124 http://example.com/live/out_%v.m3u8
1126 This example adds two @code{#EXT-X-MEDIA} tags with @code{TYPE=CLOSED-CAPTIONS} in
1127 the master playlist for the INSTREAM-IDs 'CC1' and 'CC2'. Also, it adds
1128 @code{CLOSED-CAPTIONS} attribute with group name 'cc' for the two output variant
1131 @item master_pl_name
1132 Create HLS master playlist with the given name.
1135 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
1137 This example creates HLS master playlist with name master.m3u8 and it is
1138 published at http://example.com/live/
1140 @item master_pl_publish_rate
1141 Publish master play list repeatedly every after specified number of segment intervals.
1144 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
1145 -hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
1148 This example creates HLS master playlist with name master.m3u8 and keep
1149 publishing it repeatedly every after 30 segments i.e. every after 60s.
1151 @item http_persistent
1152 Use persistent HTTP connections. Applicable only for HTTP output.
1155 Set timeout for socket I/O operations. Applicable only for HTTP output.
1157 @item -ignore_io_errors
1158 Ignore IO errors during open, write and delete. Useful for long-duration runs with network output.
1161 Set custom HTTP headers, can override built in default headers. Applicable only for HTTP output.
1170 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
1174 Size cannot exceed 256 pixels in any dimension
1177 Only BMP and PNG images can be stored
1180 If a BMP image is used, it must be one of the following pixel formats:
1182 BMP Bit Depth FFmpeg Pixel Format
1192 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
1195 If a PNG image is used, it must use the rgba pixel format
1203 The image file muxer writes video frames to image files.
1205 The output filenames are specified by a pattern, which can be used to
1206 produce sequentially numbered series of files.
1207 The pattern may contain the string "%d" or "%0@var{N}d", this string
1208 specifies the position of the characters representing a numbering in
1209 the filenames. If the form "%0@var{N}d" is used, the string
1210 representing the number in each filename is 0-padded to @var{N}
1211 digits. The literal character '%' can be specified in the pattern with
1214 If the pattern contains "%d" or "%0@var{N}d", the first filename of
1215 the file list specified will contain the number 1, all the following
1216 numbers will be sequential.
1218 The pattern may contain a suffix which is used to automatically
1219 determine the format of the image files to write.
1221 For example the pattern "img-%03d.bmp" will specify a sequence of
1222 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
1223 @file{img-010.bmp}, etc.
1224 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
1225 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
1228 The image muxer supports the .Y.U.V image file format. This format is
1229 special in that that each image frame consists of three files, for
1230 each of the YUV420P components. To read or write this image file format,
1231 specify the name of the '.Y' file. The muxer will automatically open the
1232 '.U' and '.V' files as required.
1238 If set to 1, expand the filename with pts from pkt->pts.
1242 Start the sequence from the specified number. Default value is 1.
1245 If set to 1, the filename will always be interpreted as just a
1246 filename, not a pattern, and the corresponding file will be continuously
1247 overwritten with new images. Default value is 0.
1250 If set to 1, expand the filename with date and time information from
1251 @code{strftime()}. Default value is 0.
1253 @item protocol_opts @var{options_list}
1254 Set protocol options as a :-separated list of key=value parameters. Values
1255 containing the @code{:} special character must be escaped.
1259 @subsection Examples
1261 The following example shows how to use @command{ffmpeg} for creating a
1262 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
1263 taking one image every second from the input video:
1265 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
1268 Note that with @command{ffmpeg}, if the format is not specified with the
1269 @code{-f} option and the output filename specifies an image file
1270 format, the image2 muxer is automatically selected, so the previous
1271 command can be written as:
1273 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
1276 Note also that the pattern must not necessarily contain "%d" or
1277 "%0@var{N}d", for example to create a single image file
1278 @file{img.jpeg} from the start of the input video you can employ the command:
1280 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
1283 The @option{strftime} option allows you to expand the filename with
1284 date and time information. Check the documentation of
1285 the @code{strftime()} function for the syntax.
1287 For example to generate image files from the @code{strftime()}
1288 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
1291 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
1294 You can set the file name with current frame's PTS:
1296 ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
1299 A more complex example is to publish contents of your desktop directly to a
1300 WebDAV server every second:
1302 ffmpeg -f x11grab -framerate 1 -i :0.0 -q:v 6 -update 1 -protocol_opts method=PUT http://example.com/desktop.jpg
1307 Matroska container muxer.
1309 This muxer implements the matroska and webm container specs.
1311 @subsection Metadata
1313 The recognized metadata settings in this muxer are:
1317 Set title name provided to a single track.
1320 Specify the language of the track in the Matroska languages form.
1322 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
1323 639-2/B) form (like "fre" for French), or a language code mixed with a
1324 country code for specialities in languages (like "fre-ca" for Canadian
1328 Set stereo 3D video layout of two views in a single video track.
1330 The following values are recognized:
1335 Both views are arranged side by side, Left-eye view is on the left
1337 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
1339 Both views are arranged in top-bottom orientation, Left-eye view is on top
1340 @item checkerboard_rl
1341 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
1342 @item checkerboard_lr
1343 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
1344 @item row_interleaved_rl
1345 Each view is constituted by a row based interleaving, Right-eye view is first row
1346 @item row_interleaved_lr
1347 Each view is constituted by a row based interleaving, Left-eye view is first row
1348 @item col_interleaved_rl
1349 Both views are arranged in a column based interleaving manner, Right-eye view is first column
1350 @item col_interleaved_lr
1351 Both views are arranged in a column based interleaving manner, Left-eye view is first column
1352 @item anaglyph_cyan_red
1353 All frames are in anaglyph format viewable through red-cyan filters
1355 Both views are arranged side by side, Right-eye view is on the left
1356 @item anaglyph_green_magenta
1357 All frames are in anaglyph format viewable through green-magenta filters
1359 Both eyes laced in one Block, Left-eye view is first
1361 Both eyes laced in one Block, Right-eye view is first
1365 For example a 3D WebM clip can be created using the following command line:
1367 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
1372 This muxer supports the following options:
1375 @item reserve_index_space
1376 By default, this muxer writes the index for seeking (called cues in Matroska
1377 terms) at the end of the file, because it cannot know in advance how much space
1378 to leave for the index at the beginning of the file. However for some use cases
1379 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
1380 index at the beginning of the file.
1382 If this option is set to a non-zero value, the muxer will reserve a given amount
1383 of space in the file header and then try to write the cues there when the muxing
1384 finishes. If the reserved space does not suffice, no Cues will be written, the
1385 file will be finalized and writing the trailer will return an error.
1386 A safe size for most use cases should be about 50kB per hour of video.
1388 Note that cues are only written if the output is seekable and this option will
1389 have no effect if it is not.
1391 This option controls how the FlagDefault of the output tracks will be set.
1392 It influences which tracks players should play by default. The default mode
1396 In this mode, for each type of track (audio, video or subtitle), if there is
1397 a track with disposition default of this type, then the first such track
1398 (i.e. the one with the lowest index) will be marked as default; if no such
1399 track exists, the first track of this type will be marked as default instead
1400 (if existing). This ensures that the default flag is set in a sensible way even
1401 if the input originated from containers that lack the concept of default tracks.
1403 This mode is the same as infer except that if no subtitle track with
1404 disposition default exists, no subtitle track will be marked as default.
1406 In this mode the FlagDefault is set if and only if the AV_DISPOSITION_DEFAULT
1407 flag is set in the disposition of the corresponding stream.
1416 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
1417 defaults to using the MD5 hash function.
1419 @subsection Examples
1421 To compute the MD5 hash of the input converted to raw
1422 audio and video, and store it in the file @file{out.md5}:
1424 ffmpeg -i INPUT -f md5 out.md5
1427 You can print the MD5 to stdout with the command:
1429 ffmpeg -i INPUT -f md5 -
1432 See also the @ref{hash} and @ref{framemd5} muxers.
1434 @section mov, mp4, ismv
1436 MOV/MP4/ISMV (Smooth Streaming) muxer.
1438 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
1439 file has all the metadata about all packets stored in one location
1440 (written at the end of the file, it can be moved to the start for
1441 better playback by adding @var{faststart} to the @var{movflags}, or
1442 using the @command{qt-faststart} tool). A fragmented
1443 file consists of a number of fragments, where packets and metadata
1444 about these packets are stored together. Writing a fragmented
1445 file has the advantage that the file is decodable even if the
1446 writing is interrupted (while a normal MOV/MP4 is undecodable if
1447 it is not properly finished), and it requires less memory when writing
1448 very long files (since writing normal MOV/MP4 files stores info about
1449 every single packet in memory until the file is closed). The downside
1450 is that it is less compatible with other applications.
1454 Fragmentation is enabled by setting one of the AVOptions that define
1455 how to cut the file into fragments:
1458 @item -moov_size @var{bytes}
1459 Reserves space for the moov atom at the beginning of the file instead of placing the
1460 moov atom at the end. If the space reserved is insufficient, muxing will fail.
1461 @item -movflags frag_keyframe
1462 Start a new fragment at each video keyframe.
1463 @item -frag_duration @var{duration}
1464 Create fragments that are @var{duration} microseconds long.
1465 @item -frag_size @var{size}
1466 Create fragments that contain up to @var{size} bytes of payload data.
1467 @item -movflags frag_custom
1468 Allow the caller to manually choose when to cut fragments, by
1469 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
1470 the packets written so far. (This is only useful with other
1471 applications integrating libavformat, not from @command{ffmpeg}.)
1472 @item -min_frag_duration @var{duration}
1473 Don't create fragments that are shorter than @var{duration} microseconds long.
1476 If more than one condition is specified, fragments are cut when
1477 one of the specified conditions is fulfilled. The exception to this is
1478 @code{-min_frag_duration}, which has to be fulfilled for any of the other
1479 conditions to apply.
1481 Additionally, the way the output file is written can be adjusted
1482 through a few other options:
1485 @item -movflags empty_moov
1486 Write an initial moov atom directly at the start of the file, without
1487 describing any samples in it. Generally, an mdat/moov pair is written
1488 at the start of the file, as a normal MOV/MP4 file, containing only
1489 a short portion of the file. With this option set, there is no initial
1490 mdat atom, and the moov atom only describes the tracks but has
1493 This option is implicitly set when writing ismv (Smooth Streaming) files.
1494 @item -movflags separate_moof
1495 Write a separate moof (movie fragment) atom for each track. Normally,
1496 packets for all tracks are written in a moof atom (which is slightly
1497 more efficient), but with this option set, the muxer writes one moof/mdat
1498 pair for each track, making it easier to separate tracks.
1500 This option is implicitly set when writing ismv (Smooth Streaming) files.
1501 @item -movflags skip_sidx
1502 Skip writing of sidx atom. When bitrate overhead due to sidx atom is high,
1503 this option could be used for cases where sidx atom is not mandatory.
1504 When global_sidx flag is enabled, this option will be ignored.
1505 @item -movflags faststart
1506 Run a second pass moving the index (moov atom) to the beginning of the file.
1507 This operation can take a while, and will not work in various situations such
1508 as fragmented output, thus it is not enabled by default.
1509 @item -movflags rtphint
1510 Add RTP hinting tracks to the output file.
1511 @item -movflags disable_chpl
1512 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
1513 and a QuickTime chapter track are written to the file. With this option
1514 set, only the QuickTime chapter track will be written. Nero chapters can
1515 cause failures when the file is reprocessed with certain tagging programs, like
1516 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
1517 @item -movflags omit_tfhd_offset
1518 Do not write any absolute base_data_offset in tfhd atoms. This avoids
1519 tying fragments to absolute byte positions in the file/streams.
1520 @item -movflags default_base_moof
1521 Similarly to the omit_tfhd_offset, this flag avoids writing the
1522 absolute base_data_offset field in tfhd atoms, but does so by using
1523 the new default-base-is-moof flag instead. This flag is new from
1524 14496-12:2012. This may make the fragments easier to parse in certain
1525 circumstances (avoiding basing track fragment location calculations
1526 on the implicit end of the previous track fragment).
1528 Specify @code{on} to force writing a timecode track, @code{off} to disable it
1529 and @code{auto} to write a timecode track only for mov and mp4 output (default).
1530 @item -movflags negative_cts_offsets
1531 Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
1532 be negative. This enables the initial sample to have DTS/CTS of zero, and
1533 reduces the need for edit lists for some cases such as video tracks with
1534 B-frames. Additionally, eases conformance with the DASH-IF interoperability
1537 This option is implicitly set when writing ismv (Smooth Streaming) files.
1539 Write producer time reference box (PRFT) with a specified time source for the
1540 NTP field in the PRFT box. Set value as @samp{wallclock} to specify timesource
1541 as wallclock time and @samp{pts} to specify timesource as input packets' PTS
1544 Setting value to @samp{pts} is applicable only for a live encoding use case,
1545 where PTS values are set as as wallclock time at the source. For example, an
1546 encoding use case with decklink capture source where @option{video_pts} and
1547 @option{audio_pts} are set to @samp{abs_wallclock}.
1552 Smooth Streaming content can be pushed in real time to a publishing
1553 point on IIS with this muxer. Example:
1555 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
1560 The MP3 muxer writes a raw MP3 stream with the following optional features:
1563 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
1564 2.4 are supported, the @code{id3v2_version} private option controls which one is
1565 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
1568 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
1569 The pictures are supplied to the muxer in form of a video stream with a single
1570 packet. There can be any number of those streams, each will correspond to a
1571 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
1572 to APIC @var{description} and @var{picture type} respectively. See
1573 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
1575 Note that the APIC frames must be written at the beginning, so the muxer will
1576 buffer the audio frames until it gets all the pictures. It is therefore advised
1577 to provide the pictures as soon as possible to avoid excessive buffering.
1580 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
1581 default, but will be written only if the output is seekable. The
1582 @code{write_xing} private option can be used to disable it. The frame contains
1583 various information that may be useful to the decoder, like the audio duration
1587 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1588 enabled with the @code{write_id3v1} private option, but as its capabilities are
1589 very limited, its usage is not recommended.
1594 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1596 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1599 To attach a picture to an mp3 file select both the audio and the picture stream
1602 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1603 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1606 Write a "clean" MP3 without any extra features:
1608 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1613 MPEG transport stream muxer.
1615 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1617 The recognized metadata settings in mpegts muxer are @code{service_provider}
1618 and @code{service_name}. If they are not set the default for
1619 @code{service_provider} is @samp{FFmpeg} and the default for
1620 @code{service_name} is @samp{Service01}.
1624 The muxer options are:
1627 @item mpegts_transport_stream_id @var{integer}
1628 Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
1629 Default is @code{0x0001}.
1631 @item mpegts_original_network_id @var{integer}
1632 Set the @samp{original_network_id}. This is unique identifier of a
1633 network in DVB. Its main use is in the unique identification of a service
1634 through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
1637 @item mpegts_service_id @var{integer}
1638 Set the @samp{service_id}, also known as program in DVB. Default is
1641 @item mpegts_service_type @var{integer}
1642 Set the program @samp{service_type}. Default is @code{digital_tv}.
1643 Accepts the following options:
1646 Any hexadecimal value between @code{0x01} and @code{0xff} as defined in
1651 Digital Radio service.
1654 @item advanced_codec_digital_radio
1655 Advanced Codec Digital Radio service.
1656 @item mpeg2_digital_hdtv
1657 MPEG2 Digital HDTV service.
1658 @item advanced_codec_digital_sdtv
1659 Advanced Codec Digital SDTV service.
1660 @item advanced_codec_digital_hdtv
1661 Advanced Codec Digital HDTV service.
1664 @item mpegts_pmt_start_pid @var{integer}
1665 Set the first PID for PMTs. Default is @code{0x1000}, minimum is @code{0x0020},
1666 maximum is @code{0x1ffa}. This option has no effect in m2ts mode where the PMT
1667 PID is fixed @code{0x0100}.
1669 @item mpegts_start_pid @var{integer}
1670 Set the first PID for elementary streams. Default is @code{0x0100}, minimum is
1671 @code{0x0020}, maximum is @code{0x1ffa}. This option has no effect in m2ts mode
1672 where the elementary stream PIDs are fixed.
1674 @item mpegts_m2ts_mode @var{boolean}
1675 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
1678 @item muxrate @var{integer}
1679 Set a constant muxrate. Default is VBR.
1681 @item pes_payload_size @var{integer}
1682 Set minimum PES packet payload in bytes. Default is @code{2930}.
1684 @item mpegts_flags @var{flags}
1685 Set mpegts flags. Accepts the following options:
1687 @item resend_headers
1688 Reemit PAT/PMT before writing the next packet.
1690 Use LATM packetization for AAC.
1691 @item pat_pmt_at_frames
1692 Reemit PAT and PMT at each video frame.
1694 Conform to System B (DVB) instead of System A (ATSC).
1695 @item initial_discontinuity
1696 Mark the initial packet of each stream as discontinuity.
1699 @item mpegts_copyts @var{boolean}
1700 Preserve original timestamps, if value is set to @code{1}. Default value
1701 is @code{-1}, which results in shifting timestamps so that they start from 0.
1703 @item omit_video_pes_length @var{boolean}
1704 Omit the PES packet length for video packets. Default is @code{1} (true).
1706 @item pcr_period @var{integer}
1707 Override the default PCR retransmission time in milliseconds. Default is
1708 @code{-1} which means that the PCR interval will be determined automatically:
1709 20 ms is used for CBR streams, the highest multiple of the frame duration which
1710 is less than 100 ms is used for VBR streams.
1712 @item pat_period @var{duration}
1713 Maximum time in seconds between PAT/PMT tables. Default is @code{0.1}.
1715 @item sdt_period @var{duration}
1716 Maximum time in seconds between SDT tables. Default is @code{0.5}.
1718 @item tables_version @var{integer}
1719 Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
1720 This option allows updating stream structure so that standard consumer may
1721 detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
1722 usage) or restart @command{ffmpeg} instance, cyclically changing
1723 @option{tables_version} value:
1726 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1727 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1729 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1730 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1731 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1739 ffmpeg -i file.mpg -c copy \
1740 -mpegts_original_network_id 0x1122 \
1741 -mpegts_transport_stream_id 0x3344 \
1742 -mpegts_service_id 0x5566 \
1743 -mpegts_pmt_start_pid 0x1500 \
1744 -mpegts_start_pid 0x150 \
1745 -metadata service_provider="Some provider" \
1746 -metadata service_name="Some Channel" \
1750 @section mxf, mxf_d10, mxf_opatom
1756 The muxer options are:
1759 @item store_user_comments @var{bool}
1760 Set if user comments should be stored if available or never.
1761 IRT D-10 does not allow user comments. The default is thus to write them for
1762 mxf and mxf_opatom but not for mxf_d10
1769 This muxer does not generate any output file, it is mainly useful for
1770 testing or benchmarking purposes.
1772 For example to benchmark decoding with @command{ffmpeg} you can use the
1775 ffmpeg -benchmark -i INPUT -f null out.null
1778 Note that the above command does not read or write the @file{out.null}
1779 file, but specifying the output file is required by the @command{ffmpeg}
1782 Alternatively you can write the command as:
1784 ffmpeg -benchmark -i INPUT -f null -
1790 @item -syncpoints @var{flags}
1791 Change the syncpoint usage in nut:
1793 @item @var{default} use the normal low-overhead seeking aids.
1794 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1795 Use of this option is not recommended, as the resulting files are very damage
1796 sensitive and seeking is not possible. Also in general the overhead from
1797 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1798 all growing data tables, allowing to mux endless streams with limited memory
1799 and without these disadvantages.
1800 @item @var{timestamped} extend the syncpoint with a wallclock field.
1802 The @var{none} and @var{timestamped} flags are experimental.
1803 @item -write_index @var{bool}
1804 Write index at the end, the default is to write an index.
1808 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1813 Ogg container muxer.
1816 @item -page_duration @var{duration}
1817 Preferred page duration, in microseconds. The muxer will attempt to create
1818 pages that are approximately @var{duration} microseconds long. This allows the
1819 user to compromise between seek granularity and container overhead. The default
1820 is 1 second. A value of 0 will fill all segments, making pages as large as
1821 possible. A value of 1 will effectively use 1 packet-per-page in most
1822 situations, giving a small seek granularity at the cost of additional container
1824 @item -serial_offset @var{value}
1825 Serial value from which to set the streams serial number.
1826 Setting it to different and sufficiently large values ensures that the produced
1827 ogg files can be safely chained.
1832 @section segment, stream_segment, ssegment
1834 Basic stream segmenter.
1836 This muxer outputs streams to a number of separate files of nearly
1837 fixed duration. Output filename pattern can be set in a fashion
1838 similar to @ref{image2}, or by using a @code{strftime} template if
1839 the @option{strftime} option is enabled.
1841 @code{stream_segment} is a variant of the muxer used to write to
1842 streaming output formats, i.e. which do not require global headers,
1843 and is recommended for outputting e.g. to MPEG transport stream segments.
1844 @code{ssegment} is a shorter alias for @code{stream_segment}.
1846 Every segment starts with a keyframe of the selected reference stream,
1847 which is set through the @option{reference_stream} option.
1849 Note that if you want accurate splitting for a video file, you need to
1850 make the input key frames correspond to the exact splitting times
1851 expected by the segmenter, or the segment muxer will start the new
1852 segment with the key frame found next after the specified start
1855 The segment muxer works best with a single constant frame rate video.
1857 Optionally it can generate a list of the created segments, by setting
1858 the option @var{segment_list}. The list type is specified by the
1859 @var{segment_list_type} option. The entry filenames in the segment
1860 list are set by default to the basename of the corresponding segment
1863 See also the @ref{hls} muxer, which provides a more specific
1864 implementation for HLS segmentation.
1868 The segment muxer supports the following options:
1871 @item increment_tc @var{1|0}
1872 if set to @code{1}, increment timecode between each segment
1873 If this is selected, the input need to have
1874 a timecode in the first video stream. Default value is
1877 @item reference_stream @var{specifier}
1878 Set the reference stream, as specified by the string @var{specifier}.
1879 If @var{specifier} is set to @code{auto}, the reference is chosen
1880 automatically. Otherwise it must be a stream specifier (see the ``Stream
1881 specifiers'' chapter in the ffmpeg manual) which specifies the
1882 reference stream. The default value is @code{auto}.
1884 @item segment_format @var{format}
1885 Override the inner container format, by default it is guessed by the filename
1888 @item segment_format_options @var{options_list}
1889 Set output format options using a :-separated list of key=value
1890 parameters. Values containing the @code{:} special character must be
1893 @item segment_list @var{name}
1894 Generate also a listfile named @var{name}. If not specified no
1895 listfile is generated.
1897 @item segment_list_flags @var{flags}
1898 Set flags affecting the segment list generation.
1900 It currently supports the following flags:
1903 Allow caching (only affects M3U8 list files).
1906 Allow live-friendly file generation.
1909 @item segment_list_size @var{size}
1910 Update the list file so that it contains at most @var{size}
1911 segments. If 0 the list file will contain all the segments. Default
1914 @item segment_list_entry_prefix @var{prefix}
1915 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1916 By default no prefix is applied.
1918 @item segment_list_type @var{type}
1919 Select the listing format.
1921 The following values are recognized:
1924 Generate a flat list for the created segments, one segment per line.
1927 Generate a list for the created segments, one segment per line,
1928 each line matching the format (comma-separated values):
1930 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1933 @var{segment_filename} is the name of the output file generated by the
1934 muxer according to the provided pattern. CSV escaping (according to
1935 RFC4180) is applied if required.
1937 @var{segment_start_time} and @var{segment_end_time} specify
1938 the segment start and end time expressed in seconds.
1940 A list file with the suffix @code{".csv"} or @code{".ext"} will
1941 auto-select this format.
1943 @samp{ext} is deprecated in favor or @samp{csv}.
1946 Generate an ffconcat file for the created segments. The resulting file
1947 can be read using the FFmpeg @ref{concat} demuxer.
1949 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1950 auto-select this format.
1953 Generate an extended M3U8 file, version 3, compliant with
1954 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1956 A list file with the suffix @code{".m3u8"} will auto-select this format.
1959 If not specified the type is guessed from the list file name suffix.
1961 @item segment_time @var{time}
1962 Set segment duration to @var{time}, the value must be a duration
1963 specification. Default value is "2". See also the
1964 @option{segment_times} option.
1966 Note that splitting may not be accurate, unless you force the
1967 reference stream key-frames at the given time. See the introductory
1968 notice and the examples below.
1970 @item segment_atclocktime @var{1|0}
1971 If set to "1" split at regular clock time intervals starting from 00:00
1972 o'clock. The @var{time} value specified in @option{segment_time} is
1973 used for setting the length of the splitting interval.
1975 For example with @option{segment_time} set to "900" this makes it possible
1976 to create files at 12:00 o'clock, 12:15, 12:30, etc.
1978 Default value is "0".
1980 @item segment_clocktime_offset @var{duration}
1981 Delay the segment splitting times with the specified duration when using
1982 @option{segment_atclocktime}.
1984 For example with @option{segment_time} set to "900" and
1985 @option{segment_clocktime_offset} set to "300" this makes it possible to
1986 create files at 12:05, 12:20, 12:35, etc.
1988 Default value is "0".
1990 @item segment_clocktime_wrap_duration @var{duration}
1991 Force the segmenter to only start a new segment if a packet reaches the muxer
1992 within the specified duration after the segmenting clock time. This way you
1993 can make the segmenter more resilient to backward local time jumps, such as
1994 leap seconds or transition to standard time from daylight savings time.
1996 Default is the maximum possible duration which means starting a new segment
1997 regardless of the elapsed time since the last clock time.
1999 @item segment_time_delta @var{delta}
2000 Specify the accuracy time when selecting the start time for a
2001 segment, expressed as a duration specification. Default value is "0".
2003 When delta is specified a key-frame will start a new segment if its
2004 PTS satisfies the relation:
2006 PTS >= start_time - time_delta
2009 This option is useful when splitting video content, which is always
2010 split at GOP boundaries, in case a key frame is found just before the
2011 specified split time.
2013 In particular may be used in combination with the @file{ffmpeg} option
2014 @var{force_key_frames}. The key frame times specified by
2015 @var{force_key_frames} may not be set accurately because of rounding
2016 issues, with the consequence that a key frame time may result set just
2017 before the specified time. For constant frame rate videos a value of
2018 1/(2*@var{frame_rate}) should address the worst case mismatch between
2019 the specified time and the time set by @var{force_key_frames}.
2021 @item segment_times @var{times}
2022 Specify a list of split points. @var{times} contains a list of comma
2023 separated duration specifications, in increasing order. See also
2024 the @option{segment_time} option.
2026 @item segment_frames @var{frames}
2027 Specify a list of split video frame numbers. @var{frames} contains a
2028 list of comma separated integer numbers, in increasing order.
2030 This option specifies to start a new segment whenever a reference
2031 stream key frame is found and the sequential number (starting from 0)
2032 of the frame is greater or equal to the next value in the list.
2034 @item segment_wrap @var{limit}
2035 Wrap around segment index once it reaches @var{limit}.
2037 @item segment_start_number @var{number}
2038 Set the sequence number of the first segment. Defaults to @code{0}.
2040 @item strftime @var{1|0}
2041 Use the @code{strftime} function to define the name of the new
2042 segments to write. If this is selected, the output segment name must
2043 contain a @code{strftime} function template. Default value is
2046 @item break_non_keyframes @var{1|0}
2047 If enabled, allow segments to start on frames other than keyframes. This
2048 improves behavior on some players when the time between keyframes is
2049 inconsistent, but may make things worse on others, and can cause some oddities
2050 during seeking. Defaults to @code{0}.
2052 @item reset_timestamps @var{1|0}
2053 Reset timestamps at the beginning of each segment, so that each segment
2054 will start with near-zero timestamps. It is meant to ease the playback
2055 of the generated segments. May not work with some combinations of
2056 muxers/codecs. It is set to @code{0} by default.
2058 @item initial_offset @var{offset}
2059 Specify timestamp offset to apply to the output packet timestamps. The
2060 argument must be a time duration specification, and defaults to 0.
2062 @item write_empty_segments @var{1|0}
2063 If enabled, write an empty segment if there are no packets during the period a
2064 segment would usually span. Otherwise, the segment will be filled with the next
2065 packet written. Defaults to @code{0}.
2068 Make sure to require a closed GOP when encoding and to set the GOP
2069 size to fit your segment time constraint.
2071 @subsection Examples
2075 Remux the content of file @file{in.mkv} to a list of segments
2076 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
2077 generated segments to @file{out.list}:
2079 ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
2083 Segment input and set output format options for the output segments:
2085 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
2089 Segment the input file according to the split points specified by the
2090 @var{segment_times} option:
2092 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
2096 Use the @command{ffmpeg} @option{force_key_frames}
2097 option to force key frames in the input at the specified location, together
2098 with the segment option @option{segment_time_delta} to account for
2099 possible roundings operated when setting key frame times.
2101 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
2102 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
2104 In order to force key frames on the input file, transcoding is
2108 Segment the input file by splitting the input file according to the
2109 frame numbers sequence specified with the @option{segment_frames} option:
2111 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
2115 Convert the @file{in.mkv} to TS segments using the @code{libx264}
2116 and @code{aac} encoders:
2118 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
2122 Segment the input file, and create an M3U8 live playlist (can be used
2123 as live HLS source):
2125 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
2126 -segment_list_flags +live -segment_time 10 out%03d.mkv
2130 @section smoothstreaming
2132 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
2136 Specify the number of fragments kept in the manifest. Default 0 (keep all).
2138 @item extra_window_size
2139 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
2141 @item lookahead_count
2142 Specify the number of lookahead fragments. Default 2.
2144 @item min_frag_duration
2145 Specify the minimum fragment duration (in microseconds). Default 5000000.
2147 @item remove_at_exit
2148 Specify whether to remove all fragments when finished. Default 0 (do not remove).
2155 Per stream hash testing format.
2157 This muxer computes and prints a cryptographic hash of all the input frames,
2158 on a per-stream basis. This can be used for equality checks without having
2159 to do a complete binary comparison.
2161 By default audio frames are converted to signed 16-bit raw audio and
2162 video frames to raw video before computing the hash, but the output
2163 of explicit conversions to other codecs can also be used. Timestamps
2164 are ignored. It uses the SHA-256 cryptographic hash function by default,
2165 but supports several other algorithms.
2167 The output of the muxer consists of one line per stream of the form:
2168 @var{streamindex},@var{streamtype},@var{algo}=@var{hash}, where
2169 @var{streamindex} is the index of the mapped stream, @var{streamtype} is a
2170 single character indicating the type of stream, @var{algo} is a short string
2171 representing the hash function used, and @var{hash} is a hexadecimal number
2172 representing the computed hash.
2175 @item hash @var{algorithm}
2176 Use the cryptographic hash function specified by the string @var{algorithm}.
2177 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
2178 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
2179 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
2180 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
2184 @subsection Examples
2186 To compute the SHA-256 hash of the input converted to raw audio and
2187 video, and store it in the file @file{out.sha256}:
2189 ffmpeg -i INPUT -f streamhash out.sha256
2192 To print an MD5 hash to stdout use the command:
2194 ffmpeg -i INPUT -f streamhash -hash md5 -
2197 See also the @ref{hash} and @ref{framehash} muxers.
2202 The fifo pseudo-muxer allows the separation of encoding and muxing by using
2203 first-in-first-out queue and running the actual muxer in a separate thread. This
2204 is especially useful in combination with the @ref{tee} muxer and can be used to
2205 send data to several destinations with different reliability/writing speed/latency.
2207 API users should be aware that callback functions (interrupt_callback,
2208 io_open and io_close) used within its AVFormatContext must be thread-safe.
2210 The behavior of the fifo muxer if the queue fills up or if the output fails is
2216 output can be transparently restarted with configurable delay between retries
2217 based on real time or time of the processed stream.
2220 encoding can be blocked during temporary failure, or continue transparently
2221 dropping packets in case fifo queue fills up.
2228 Specify the format name. Useful if it cannot be guessed from the
2232 Specify size of the queue (number of packets). Default value is 60.
2235 Specify format options for the underlying muxer. Muxer options can be specified
2236 as a list of @var{key}=@var{value} pairs separated by ':'.
2238 @item drop_pkts_on_overflow @var{bool}
2239 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
2240 rather than blocking the encoder. This makes it possible to continue streaming without
2241 delaying the input, at the cost of omitting part of the stream. By default
2242 this option is set to 0 (false), so in such cases the encoder will be blocked
2243 until the muxer processes some of the packets and none of them is lost.
2245 @item attempt_recovery @var{bool}
2246 If failure occurs, attempt to recover the output. This is especially useful
2247 when used with network output, since it makes it possible to restart streaming transparently.
2248 By default this option is set to 0 (false).
2250 @item max_recovery_attempts
2251 Sets maximum number of successive unsuccessful recovery attempts after which
2252 the output fails permanently. By default this option is set to 0 (unlimited).
2254 @item recovery_wait_time @var{duration}
2255 Waiting time before the next recovery attempt after previous unsuccessful
2256 recovery attempt. Default value is 5 seconds.
2258 @item recovery_wait_streamtime @var{bool}
2259 If set to 0 (false), the real time is used when waiting for the recovery
2260 attempt (i.e. the recovery will be attempted after at least
2261 recovery_wait_time seconds).
2262 If set to 1 (true), the time of the processed stream is taken into account
2263 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
2264 seconds of the stream is omitted).
2265 By default, this option is set to 0 (false).
2267 @item recover_any_error @var{bool}
2268 If set to 1 (true), recovery will be attempted regardless of type of the error
2269 causing the failure. By default this option is set to 0 (false) and in case of
2270 certain (usually permanent) errors the recovery is not attempted even when
2271 @var{attempt_recovery} is set to 1.
2273 @item restart_with_keyframe @var{bool}
2274 Specify whether to wait for the keyframe after recovering from
2275 queue overflow or failure. This option is set to 0 (false) by default.
2279 @subsection Examples
2284 Stream something to rtmp server, continue processing the stream at real-time
2285 rate even in case of temporary failure (network outage) and attempt to recover
2286 streaming every second indefinitely.
2288 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
2289 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
2297 The tee muxer can be used to write the same data to several outputs, such as files or streams.
2298 It can be used, for example, to stream a video over a network and save it to disk at the same time.
2300 It is different from specifying several outputs to the @command{ffmpeg}
2301 command-line tool. With the tee muxer, the audio and video data will be encoded only once.
2302 With conventional multiple outputs, multiple encoding operations in parallel are initiated,
2303 which can be a very expensive process. The tee muxer is not useful when using the libavformat API
2304 directly because it is then possible to feed the same packets to several muxers directly.
2306 Since the tee muxer does not represent any particular output format, ffmpeg cannot auto-select
2307 output streams. So all streams intended for output must be specified using @code{-map}. See
2310 Some encoders may need different options depending on the output format;
2311 the auto-detection of this can not work with the tee muxer, so they need to be explicitly specified.
2312 The main example is the @option{global_header} flag.
2314 The slave outputs are specified in the file name given to the muxer,
2315 separated by '|'. If any of the slave name contains the '|' separator,
2316 leading or trailing spaces or any special character, those must be
2317 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
2318 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
2324 @item use_fifo @var{bool}
2325 If set to 1, slave outputs will be processed in separate threads using the @ref{fifo}
2326 muxer. This allows to compensate for different speed/latency/reliability of
2327 outputs and setup transparent recovery. By default this feature is turned off.
2330 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
2334 Muxer options can be specified for each slave by prepending them as a list of
2335 @var{key}=@var{value} pairs separated by ':', between square brackets. If
2336 the options values contain a special character or the ':' separator, they
2337 must be escaped; note that this is a second level escaping.
2339 The following special options are also recognized:
2342 Specify the format name. Required if it cannot be guessed from the
2345 @item bsfs[/@var{spec}]
2346 Specify a list of bitstream filters to apply to the specified
2349 It is possible to specify to which streams a given bitstream filter
2350 applies, by appending a stream specifier to the option separated by
2351 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
2352 stream specifiers}).
2354 If the stream specifier is not specified, the bitstream filters will be
2355 applied to all streams in the output. This will cause that output operation
2356 to fail if the output contains streams to which the bitstream filter cannot
2357 be applied e.g. @code{h264_mp4toannexb} being applied to an output containing an audio stream.
2359 Options for a bitstream filter must be specified in the form of @code{opt=value}.
2361 Several bitstream filters can be specified, separated by ",".
2363 @item use_fifo @var{bool}
2364 This allows to override tee muxer use_fifo option for individual slave muxer.
2367 This allows to override tee muxer fifo_options for individual slave muxer.
2371 Select the streams that should be mapped to the slave output,
2372 specified by a stream specifier. If not specified, this defaults to
2373 all the mapped streams. This will cause that output operation to fail
2374 if the output format does not accept all mapped streams.
2376 You may use multiple stream specifiers separated by commas (@code{,}) e.g.: @code{a:0,v}
2379 Specify behaviour on output failure. This can be set to either @code{abort} (which is
2380 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
2381 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
2382 will continue without being affected.
2385 @subsection Examples
2389 Encode something and both archive it in a WebM file and stream it
2390 as MPEG-TS over UDP:
2392 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2393 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2397 As above, but continue streaming even if output to local file fails
2398 (for example local drive fills up):
2400 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2401 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2405 Use @command{ffmpeg} to encode the input, and send the output
2406 to three different destinations. The @code{dump_extra} bitstream
2407 filter is used to add extradata information to all the output video
2408 keyframes packets, as requested by the MPEG-TS format. The select
2409 option is applied to @file{out.aac} in order to make it contain only
2412 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2413 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
2417 As above, but select only stream @code{a:1} for the audio output. Note
2418 that a second level escaping must be performed, as ":" is a special
2419 character used to separate options.
2421 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2422 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
2426 @section webm_dash_manifest
2428 WebM DASH Manifest muxer.
2430 This muxer implements the WebM DASH Manifest specification to generate the DASH
2431 manifest XML. It also supports manifest generation for DASH live streams.
2433 For more information see:
2437 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
2439 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
2444 This muxer supports the following options:
2447 @item adaptation_sets
2448 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
2449 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
2450 audio and video streams. Any number of adaptation sets can be added using this option.
2453 Set this to 1 to create a live stream DASH Manifest. Default: 0.
2455 @item chunk_start_index
2456 Start index of the first chunk. This will go in the @samp{startNumber} attribute
2457 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
2459 @item chunk_duration_ms
2460 Duration of each chunk in milliseconds. This will go in the @samp{duration}
2461 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
2463 @item utc_timing_url
2464 URL of the page that will return the UTC timestamp in ISO format. This will go
2465 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
2468 @item time_shift_buffer_depth
2469 Smallest time (in seconds) shifting buffer for which any Representation is
2470 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
2471 attribute of the @samp{MPD} element. Default: 60.
2473 @item minimum_update_period
2474 Minimum update period (in seconds) of the manifest. This will go in the
2475 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
2481 ffmpeg -f webm_dash_manifest -i video1.webm \
2482 -f webm_dash_manifest -i video2.webm \
2483 -f webm_dash_manifest -i audio1.webm \
2484 -f webm_dash_manifest -i audio2.webm \
2485 -map 0 -map 1 -map 2 -map 3 \
2487 -f webm_dash_manifest \
2488 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
2494 WebM Live Chunk Muxer.
2496 This muxer writes out WebM headers and chunks as separate files which can be
2497 consumed by clients that support WebM Live streams via DASH.
2501 This muxer supports the following options:
2504 @item chunk_start_index
2505 Index of the first chunk (defaults to 0).
2508 Filename of the header where the initialization data will be written.
2510 @item audio_chunk_duration
2511 Duration of each audio chunk in milliseconds (defaults to 5000).
2516 ffmpeg -f v4l2 -i /dev/video0 \
2520 -s 640x360 -keyint_min 30 -g 30 \
2522 -header webm_live_video_360.hdr \
2523 -chunk_start_index 1 \
2524 webm_live_video_360_%d.chk \
2529 -header webm_live_audio_128.hdr \
2530 -chunk_start_index 1 \
2531 -audio_chunk_duration 1000 \
2532 webm_live_audio_128_%d.chk