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 @item timeout @var{timeout}
290 Set timeout for socket I/O operations. Applicable only for HTTP output.
291 @item index_correction @var{index_correction}
292 Enable (1) or Disable (0) segment index correction logic. Applicable only when
293 @var{use_template} is enabled and @var{use_timeline} is disabled.
295 When enabled, the logic monitors the flow of segment indexes. If a streams's
296 segment index value is not at the expected real time position, then the logic
297 corrects that index value.
299 Typically this logic is needed in live streaming use cases. The network bandwidth
300 fluctuations are common during long run streaming. Each fluctuation can cause
301 the segment indexes fall behind the expected real time position.
302 @item format_options @var{options_list}
303 Set container format (mp4/webm) options using a @code{:} separated list of
304 key=value parameters. Values containing @code{:} special characters must be
307 @item global_sidx @var{global_sidx}
308 Write global SIDX atom. Applicable only for single file, mp4 output, non-streaming mode.
310 @item dash_segment_type @var{dash_segment_type}
314 If this flag is set, the dash segment files format will be selected based on the stream codec. This is the default mode.
317 If this flag is set, the dash segment files will be in in ISOBMFF format.
320 If this flag is set, the dash segment files will be in in WebM format.
323 @item ignore_io_errors @var{ignore_io_errors}
324 Ignore IO errors during open and write. Useful for long-duration runs with network output.
326 @item lhls @var{lhls}
327 Enable Low-latency HLS(LHLS). Adds #EXT-X-PREFETCH tag with current segment's URI.
328 Apple doesn't have an official spec for LHLS. Meanwhile hls.js player folks are
329 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
330 This option will also try to comply with the above open spec, till Apple's spec officially supports it.
331 Applicable only when @var{streaming} and @var{hls_playlist} options are enabled.
332 This is an experimental feature.
334 @item ldash @var{ldash}
335 Enable Low-latency Dash by constraining the presence and values of some elements.
337 @item master_m3u8_publish_rate @var{master_m3u8_publish_rate}
338 Publish master playlist repeatedly every after specified number of segment intervals.
340 @item -write_prft @var{write_prft}
341 Write Producer Reference Time elements on supported streams. This also enables writing
342 prft boxes in the underlying muxer. Applicable only when the @var{utc_url} option is enabled.
344 @item -mpd_profile @var{mpd_profile}
345 Set one or more manifest profiles.
347 @item -http_opts @var{http_opts}
348 List of options to pass to the underlying HTTP protocol. Applicable only for HTTP output.
350 @item -target_latency @var{target_latency}
351 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.
352 This is an informative fields clients can use to measure the latency of the service.
359 Per-packet CRC (Cyclic Redundancy Check) testing format.
361 This muxer computes and prints the Adler-32 CRC for each audio
362 and video packet. By default audio frames are converted to signed
363 16-bit raw audio and video frames to raw video before computing the
366 The output of the muxer consists of a line for each audio and video
369 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
372 @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
377 For example to compute the CRC of the audio and video frames in
378 @file{INPUT}, converted to raw audio and video packets, and store it
379 in the file @file{out.crc}:
381 ffmpeg -i INPUT -f framecrc out.crc
384 To print the information to stdout, use the command:
386 ffmpeg -i INPUT -f framecrc -
389 With @command{ffmpeg}, you can select the output format to which the
390 audio and video frames are encoded before computing the CRC for each
391 packet by specifying the audio and video codec. For example, to
392 compute the CRC of each decoded input audio frame converted to PCM
393 unsigned 8-bit and of each decoded input video frame converted to
394 MPEG-2 video, use the command:
396 ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
399 See also the @ref{crc} muxer.
404 Per-packet hash testing format.
406 This muxer computes and prints a cryptographic hash for each audio
407 and video packet. This can be used for packet-by-packet equality
408 checks without having to individually do a binary comparison on each.
410 By default audio frames are converted to signed 16-bit raw audio and
411 video frames to raw video before computing the hash, but the output
412 of explicit conversions to other codecs can also be used. It uses the
413 SHA-256 cryptographic hash function by default, but supports several
416 The output of the muxer consists of a line for each audio and video
419 @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
422 @var{hash} is a hexadecimal number representing the computed hash
426 @item hash @var{algorithm}
427 Use the cryptographic hash function specified by the string @var{algorithm}.
428 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
429 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
430 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
431 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
437 To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
438 converted to raw audio and video packets, and store it in the file
441 ffmpeg -i INPUT -f framehash out.sha256
444 To print the information to stdout, using the MD5 hash function, use
447 ffmpeg -i INPUT -f framehash -hash md5 -
450 See also the @ref{hash} muxer.
455 Per-packet MD5 testing format.
457 This is a variant of the @ref{framehash} muxer. Unlike that muxer,
458 it defaults to using the MD5 hash function.
462 To compute the MD5 hash of the audio and video frames in @file{INPUT},
463 converted to raw audio and video packets, and store it in the file
466 ffmpeg -i INPUT -f framemd5 out.md5
469 To print the information to stdout, use the command:
471 ffmpeg -i INPUT -f framemd5 -
474 See also the @ref{framehash} and @ref{md5} muxers.
481 It accepts the following options:
485 Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
486 for looping indefinitely (default).
489 Force the delay (expressed in centiseconds) after the last frame. Each frame
490 ends with a delay until the next frame. The default is @code{-1}, which is a
491 special value to tell the muxer to re-use the previous delay. In case of a
492 loop, you might want to customize this value to mark a pause for instance.
495 For example, to encode a gif looping 10 times, with a 5 seconds delay between
498 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
501 Note 1: if you wish to extract the frames into separate GIF files, you need to
502 force the @ref{image2} muxer:
504 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
507 Note 2: the GIF format has a very large time base: the delay between two frames
508 can therefore not be smaller than one centi second.
515 This muxer computes and prints a cryptographic hash of all the input
516 audio and video frames. This can be used for equality checks without
517 having to do a complete binary comparison.
519 By default audio frames are converted to signed 16-bit raw audio and
520 video frames to raw video before computing the hash, but the output
521 of explicit conversions to other codecs can also be used. Timestamps
522 are ignored. It uses the SHA-256 cryptographic hash function by default,
523 but supports several other algorithms.
525 The output of the muxer consists of a single line of the form:
526 @var{algo}=@var{hash}, where @var{algo} is a short string representing
527 the hash function used, and @var{hash} is a hexadecimal number
528 representing the computed hash.
531 @item hash @var{algorithm}
532 Use the cryptographic hash function specified by the string @var{algorithm}.
533 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
534 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
535 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
536 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
542 To compute the SHA-256 hash of the input converted to raw audio and
543 video, and store it in the file @file{out.sha256}:
545 ffmpeg -i INPUT -f hash out.sha256
548 To print an MD5 hash to stdout use the command:
550 ffmpeg -i INPUT -f hash -hash md5 -
553 See also the @ref{framehash} muxer.
558 Apple HTTP Live Streaming muxer that segments MPEG-TS according to
559 the HTTP Live Streaming (HLS) specification.
561 It creates a playlist file, and one or more segment files. The output filename
562 specifies the playlist filename.
564 By default, the muxer creates a file for each segment produced. These files
565 have the same name as the playlist, followed by a sequential number and a
568 Make sure to require a closed GOP when encoding and to set the GOP
569 size to fit your segment time constraint.
571 For example, to convert an input file with @command{ffmpeg}:
573 ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
575 This example will produce the playlist, @file{out.m3u8}, and segment files:
576 @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
578 See also the @ref{segment} muxer, which provides a more generic and
579 flexible implementation of a segmenter, and can be used to perform HLS
584 This muxer supports the following options:
587 @item hls_init_time @var{seconds}
588 Set the initial target segment length in seconds. Default value is @var{0}.
589 Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
590 After the initial playlist is filled @command{ffmpeg} will cut segments
591 at duration equal to @code{hls_time}
593 @item hls_time @var{seconds}
594 Set the target segment length in seconds. Default value is 2.
595 Segment will be cut on the next key frame after this time has passed.
597 @item hls_list_size @var{size}
598 Set the maximum number of playlist entries. If set to 0 the list file
599 will contain all the segments. Default value is 5.
601 @item hls_delete_threshold @var{size}
602 Set the number of unreferenced segments to keep on disk before @code{hls_flags delete_segments}
603 deletes them. Increase this to allow continue clients to download segments which
604 were recently referenced in the playlist. Default value is 1, meaning segments older than
605 @code{hls_list_size+1} will be deleted.
607 @item hls_ts_options @var{options_list}
608 Set output format options using a :-separated list of key=value
609 parameters. Values containing @code{:} special characters must be
612 @item hls_wrap @var{wrap}
613 This is a deprecated option, you can use @code{hls_list_size}
614 and @code{hls_flags delete_segments} instead it
616 This option is useful to avoid to fill the disk with many segment
617 files, and limits the maximum number of segment files written to disk
621 @item hls_start_number_source
622 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
623 Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
624 segment and subtitle filenames. In any case, if @code{hls_flags append_list}
625 is set and read playlist sequence number is greater than the specified start sequence number,
626 then that value will be used as start value.
628 It accepts the following values:
632 @item generic (default)
633 Set the starting sequence numbers according to @var{start_number} option value.
636 The start number will be the seconds since epoch (1970-01-01 00:00:00)
639 The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
643 @item start_number @var{number}
644 Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
645 when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
646 Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
649 @item hls_allow_cache @var{allowcache}
650 Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
652 @item hls_base_url @var{baseurl}
653 Append @var{baseurl} to every entry in the playlist.
654 Useful to generate playlists with absolute paths.
656 Note that the playlist sequence number must be unique for each segment
657 and it is not to be confused with the segment filename sequence number
658 which can be cyclic, for example if the @option{wrap} option is
661 @item hls_segment_filename @var{filename}
662 Set the segment filename. Unless @code{hls_flags single_file} is set,
663 @var{filename} is used as a string format with the segment number:
665 ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
667 This example will produce the playlist, @file{out.m3u8}, and segment files:
668 @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
670 @var{filename} may contain full path or relative path specification,
671 but only the file name part without any path info will be contained in the m3u8 segment list.
672 Should a relative path be specified, the path of the created segment
673 files will be relative to the current working directory.
674 When strftime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
676 When @code{var_stream_map} is set with two or more variant streams, the
677 @var{filename} pattern must contain the string "%v", this string specifies
678 the position of variant stream index in the generated segment file names.
680 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
681 -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" \
682 -hls_segment_filename 'file_%v_%03d.ts' out_%v.m3u8
684 This example will produce the playlists segment file sets:
685 @file{file_0_000.ts}, @file{file_0_001.ts}, @file{file_0_002.ts}, etc. and
686 @file{file_1_000.ts}, @file{file_1_001.ts}, @file{file_1_002.ts}, etc.
688 The string "%v" may be present in the filename or in the last directory name
689 containing the file, but only in one of them. (Additionally, %v may appear multiple times in the last
690 sub-directory or filename.) If the string %v is present in the directory name, then
691 sub-directories are created after expanding the directory name pattern. This
692 enables creation of segments corresponding to different variant streams in
695 ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
696 -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" \
697 -hls_segment_filename 'vs%v/file_%03d.ts' vs%v/out.m3u8
699 This example will produce the playlists segment file sets:
700 @file{vs0/file_000.ts}, @file{vs0/file_001.ts}, @file{vs0/file_002.ts}, etc. and
701 @file{vs1/file_000.ts}, @file{vs1/file_001.ts}, @file{vs1/file_002.ts}, etc.
704 Same as strftime option, will be deprecated.
707 Use strftime() on @var{filename} to expand the segment filename with localtime.
708 The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
709 hls_flag and %%d will be the specifier.
711 ffmpeg -i in.nut -strftime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
713 This example will produce the playlist, @file{out.m3u8}, and segment files:
714 @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
715 Note: On some systems/environments, the @code{%s} specifier is not available. See
716 @code{strftime()} documentation.
718 ffmpeg -i in.nut -strftime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
720 This example will produce the playlist, @file{out.m3u8}, and segment files:
721 @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
723 @item use_localtime_mkdir
724 Same as strftime_mkdir option, will be deprecated .
727 Used together with -strftime_mkdir, it will create all subdirectories which
728 is expanded in @var{filename}.
730 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y%m%d/file-%Y%m%d-%s.ts' out.m3u8
732 This example will create a directory 201560215 (if it does not exist), and then
733 produce the playlist, @file{out.m3u8}, and segment files:
734 @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
737 ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y/%m/%d/file-%Y%m%d-%s.ts' out.m3u8
739 This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
740 produce the playlist, @file{out.m3u8}, and segment files:
741 @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
744 @item hls_key_info_file @var{key_info_file}
745 Use the information in @var{key_info_file} for segment encryption. The first
746 line of @var{key_info_file} specifies the key URI written to the playlist. The
747 key URL is used to access the encryption key during playback. The second line
748 specifies the path to the key file used to obtain the key during the encryption
749 process. The key file is read as a single packed array of 16 octets in binary
750 format. The optional third line specifies the initialization vector (IV) as a
751 hexadecimal string to be used instead of the segment sequence number (default)
752 for encryption. Changes to @var{key_info_file} will result in segment
753 encryption with the new key/IV and an entry in the playlist for the new key
754 URI/IV if @code{hls_flags periodic_rekey} is enabled.
756 Key info file format:
765 http://server/file.key
770 Example key file paths:
778 0123456789ABCDEF0123456789ABCDEF
781 Key info file example:
783 http://server/file.key
785 0123456789ABCDEF0123456789ABCDEF
788 Example shell script:
792 openssl rand 16 > file.key
793 echo $BASE_URL/file.key > file.keyinfo
794 echo file.key >> file.keyinfo
795 echo $(openssl rand -hex 16) >> file.keyinfo
796 ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
797 -hls_key_info_file file.keyinfo out.m3u8
800 @item -hls_enc @var{enc}
801 Enable (1) or disable (0) the AES128 encryption.
802 When enabled every segment generated is encrypted and the encryption key
803 is saved as @var{playlist name}.key.
805 @item -hls_enc_key @var{key}
806 Hex-coded 16byte key to encrypt the segments, by default it
807 is randomly generated.
809 @item -hls_enc_key_url @var{keyurl}
810 If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
813 @item -hls_enc_iv @var{iv}
814 Hex-coded 16byte initialization vector for every segment instead
815 of the autogenerated ones.
817 @item hls_segment_type @var{flags}
822 Output segment files in MPEG-2 Transport Stream format. This is
823 compatible with all HLS versions.
826 Output segment files in fragmented MP4 format, similar to MPEG-DASH.
827 fmp4 files may be used in HLS version 7 and above.
831 @item hls_fmp4_init_filename @var{filename}
832 Set filename to the fragment files header file, default filename is @file{init.mp4}.
834 When @code{var_stream_map} is set with two or more variant streams, the
835 @var{filename} pattern must contain the string "%v", this string specifies
836 the position of variant stream index in the generated init file names.
837 The string "%v" may be present in the filename or in the last directory name
838 containing the file. If the string is present in the directory name, then
839 sub-directories are created after expanding the directory name pattern. This
840 enables creation of init files corresponding to different variant streams in
843 @item hls_flags @var{flags}
848 If this flag is set, the muxer will store all segments in a single MPEG-TS
849 file, and will use byte ranges in the playlist. HLS playlists generated with
850 this way will have the version number 4.
853 ffmpeg -i in.nut -hls_flags single_file out.m3u8
855 Will produce the playlist, @file{out.m3u8}, and a single segment file,
858 @item delete_segments
859 Segment files removed from the playlist are deleted after a period of time
860 equal to the duration of the segment plus the duration of the playlist.
863 Append new segments into the end of old segment list,
864 and remove the @code{#EXT-X-ENDLIST} from the old segment list.
866 @item round_durations
867 Round the duration info in the playlist file segment info to integer
868 values, instead of using floating point.
871 Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
872 first segment's information.
875 Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
878 The file specified by @code{hls_key_info_file} will be checked periodically and
879 detect updates to the encryption info. Be sure to replace this file atomically,
880 including the file containing the AES encryption key.
882 @item independent_segments
883 Add the @code{#EXT-X-INDEPENDENT-SEGMENTS} to playlists that has video segments
884 and when all the segments of that playlist are guaranteed to start with a Key frame.
887 Add the @code{#EXT-X-I-FRAMES-ONLY} to playlists that has video segments
888 and can play only I-frames in the @code{#EXT-X-BYTERANGE} mode.
891 Allow segments to start on frames other than keyframes. This improves
892 behavior on some players when the time between keyframes is inconsistent,
893 but may make things worse on others, and can cause some oddities during
894 seeking. This flag should be used with the @code{hls_time} option.
896 @item program_date_time
897 Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
899 @item second_level_segment_index
900 Makes it possible to use segment indexes as %%d in hls_segment_filename expression
901 besides date/time values when strftime is on.
902 To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
904 @item second_level_segment_size
905 Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
906 expression besides date/time values when strftime is on.
907 To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
909 @item second_level_segment_duration
910 Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
911 expression besides date/time values when strftime is on.
912 To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
915 ffmpeg -i sample.mpeg \
916 -f hls -hls_time 3 -hls_list_size 5 \
917 -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
918 -strftime 1 -strftime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
920 This will produce segments like this:
921 @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
924 Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
925 serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
926 before they have been added to the m3u8 playlist. This flag also affects how m3u8 playlist files are created.
927 If this flag is set, all playlist files will written into temporary file and renamed after they are complete, similarly as segments are handled.
928 But playlists with @code{file} protocol and with type (@code{hls_playlist_type}) other than @code{vod}
929 are always written into temporary file regardless of this flag. Master playlist files (@code{master_pl_name}), if any, with @code{file} protocol,
930 are always written into temporary file regardless of this flag if @code{master_pl_publish_rate} value is other than zero.
934 @item hls_playlist_type event
935 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
936 @option{hls_list_size} to 0; the playlist can only be appended to.
938 @item hls_playlist_type vod
939 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
940 @option{hls_list_size} to 0; the playlist must not change.
943 Use the given HTTP method to create the hls files.
945 ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
947 This example will upload all the mpegts segment files to the HTTP
948 server using the HTTP PUT method, and update the m3u8 files every
949 @code{refresh} times using the same method.
950 Note that the HTTP server must support the given method for uploading
953 @item http_user_agent
954 Override User-Agent field in HTTP header. Applicable only for HTTP output.
957 Map string which specifies how to group the audio, video and subtitle streams
958 into different variant streams. The variant stream groups are separated
960 Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
961 the keys to specify audio, video and subtitle streams respectively.
962 Allowed values are 0 to 9 (limited just based on practical usage).
964 When there are two or more variant streams, the output filename pattern must
965 contain the string "%v", this string specifies the position of variant stream
966 index in the output media playlist filenames. The string "%v" may be present in
967 the filename or in the last directory name containing the file. If the string is
968 present in the directory name, then sub-directories are created after expanding
969 the directory name pattern. This enables creation of variant streams in
973 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
974 -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" \
975 http://example.com/live/out_%v.m3u8
977 This example creates two hls variant streams. The first variant stream will
978 contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
979 second variant stream will contain video stream of bitrate 256k and audio
980 stream of bitrate 32k. Here, two media playlist with file names out_0.m3u8 and
981 out_1.m3u8 will be created. If you want something meaningful text instead of indexes
982 in result names, you may specify names for each or some of the variants
983 as in the following example.
987 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
988 -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" \
989 http://example.com/live/out_%v.m3u8
992 This example creates two hls variant streams as in the previous one.
993 But here, the two media playlist with file names out_my_hd.m3u8 and
994 out_my_sd.m3u8 will be created.
997 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
998 -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
999 http://example.com/live/out_%v.m3u8
1001 This example creates three hls variant streams. The first variant stream will
1002 be a video only stream with video bitrate 1000k, the second variant stream will
1003 be an audio only stream with bitrate 64k and the third variant stream will be a
1004 video only stream with bitrate 256k. Here, three media playlist with file names
1005 out_0.m3u8, out_1.m3u8 and out_2.m3u8 will be created.
1007 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1008 -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" \
1009 http://example.com/live/vs_%v/out.m3u8
1011 This example creates the variant streams in subdirectories. Here, the first
1012 media playlist is created at @file{http://example.com/live/vs_0/out.m3u8} and
1013 the second one at @file{http://example.com/live/vs_1/out.m3u8}.
1015 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k \
1016 -map 0:a -map 0:a -map 0:v -map 0:v -f hls \
1017 -var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
1018 -master_pl_name master.m3u8 \
1019 http://example.com/live/out_%v.m3u8
1021 This example creates two audio only and two video only variant streams. In
1022 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1023 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1024 and they are mapped to the two video only variant streams with audio group names
1025 'aud_low' and 'aud_high'.
1027 By default, a single hls variant containing all the encoded streams is created.
1030 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
1031 -map 0:a -map 0:a -map 0:v -f hls \
1032 -var_stream_map "a:0,agroup:aud_low,default:yes a:1,agroup:aud_low v:0,agroup:aud_low" \
1033 -master_pl_name master.m3u8 \
1034 http://example.com/live/out_%v.m3u8
1036 This example creates two audio only and one video only variant streams. In
1037 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1038 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1039 and they are mapped to the one video only variant streams with audio group name
1040 'aud_low', and the audio group have default stat is NO or YES.
1042 By default, a single hls variant containing all the encoded streams is created.
1045 ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
1046 -map 0:a -map 0:a -map 0:v -f hls \
1047 -var_stream_map "a:0,agroup:aud_low,default:yes,language:ENG a:1,agroup:aud_low,language:CHN v:0,agroup:aud_low" \
1048 -master_pl_name master.m3u8 \
1049 http://example.com/live/out_%v.m3u8
1051 This example creates two audio only and one video only variant streams. In
1052 addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
1053 playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
1054 and they are mapped to the one video only variant streams with audio group name
1055 'aud_low', and the audio group have default stat is NO or YES, and one audio
1056 have and language is named ENG, the other audio language is named CHN.
1058 By default, a single hls variant containing all the encoded streams is created.
1061 Map string which specifies different closed captions groups and their
1062 attributes. The closed captions stream groups are separated by space.
1063 Expected string format is like this
1064 "ccgroup:<group name>,instreamid:<INSTREAM-ID>,language:<language code> ....".
1065 'ccgroup' and 'instreamid' are mandatory attributes. 'language' is an optional
1067 The closed captions groups configured using this option are mapped to different
1068 variant streams by providing the same 'ccgroup' name in the
1069 @code{var_stream_map} string. If @code{var_stream_map} is not set, then the
1070 first available ccgroup in @code{cc_stream_map} is mapped to the output variant
1071 stream. The examples for these two use cases are given below.
1074 ffmpeg -re -i in.ts -b:v 1000k -b:a 64k -a53cc 1 -f hls \
1075 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en" \
1076 -master_pl_name master.m3u8 \
1077 http://example.com/live/out.m3u8
1079 This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=CLOSED-CAPTIONS} in
1080 the master playlist with group name 'cc', language 'en' (english) and
1081 INSTREAM-ID 'CC1'. Also, it adds @code{CLOSED-CAPTIONS} attribute with group
1082 name 'cc' for the output variant stream.
1084 ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
1085 -a53cc:0 1 -a53cc:1 1\
1086 -map 0:v -map 0:a -map 0:v -map 0:a -f hls \
1087 -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en ccgroup:cc,instreamid:CC2,language:sp" \
1088 -var_stream_map "v:0,a:0,ccgroup:cc v:1,a:1,ccgroup:cc" \
1089 -master_pl_name master.m3u8 \
1090 http://example.com/live/out_%v.m3u8
1092 This example adds two @code{#EXT-X-MEDIA} tags with @code{TYPE=CLOSED-CAPTIONS} in
1093 the master playlist for the INSTREAM-IDs 'CC1' and 'CC2'. Also, it adds
1094 @code{CLOSED-CAPTIONS} attribute with group name 'cc' for the two output variant
1097 @item master_pl_name
1098 Create HLS master playlist with the given name.
1101 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
1103 This example creates HLS master playlist with name master.m3u8 and it is
1104 published at http://example.com/live/
1106 @item master_pl_publish_rate
1107 Publish master play list repeatedly every after specified number of segment intervals.
1110 ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
1111 -hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
1114 This example creates HLS master playlist with name master.m3u8 and keep
1115 publishing it repeatedly every after 30 segments i.e. every after 60s.
1117 @item http_persistent
1118 Use persistent HTTP connections. Applicable only for HTTP output.
1121 Set timeout for socket I/O operations. Applicable only for HTTP output.
1123 @item -ignore_io_errors
1124 Ignore IO errors during open, write and delete. Useful for long-duration runs with network output.
1127 Set custom HTTP headers, can override built in default headers. Applicable only for HTTP output.
1136 Microsoft's icon file format (ICO) has some strict limitations that should be noted:
1140 Size cannot exceed 256 pixels in any dimension
1143 Only BMP and PNG images can be stored
1146 If a BMP image is used, it must be one of the following pixel formats:
1148 BMP Bit Depth FFmpeg Pixel Format
1158 If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
1161 If a PNG image is used, it must use the rgba pixel format
1169 The image file muxer writes video frames to image files.
1171 The output filenames are specified by a pattern, which can be used to
1172 produce sequentially numbered series of files.
1173 The pattern may contain the string "%d" or "%0@var{N}d", this string
1174 specifies the position of the characters representing a numbering in
1175 the filenames. If the form "%0@var{N}d" is used, the string
1176 representing the number in each filename is 0-padded to @var{N}
1177 digits. The literal character '%' can be specified in the pattern with
1180 If the pattern contains "%d" or "%0@var{N}d", the first filename of
1181 the file list specified will contain the number 1, all the following
1182 numbers will be sequential.
1184 The pattern may contain a suffix which is used to automatically
1185 determine the format of the image files to write.
1187 For example the pattern "img-%03d.bmp" will specify a sequence of
1188 filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
1189 @file{img-010.bmp}, etc.
1190 The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
1191 form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
1194 The image muxer supports the .Y.U.V image file format. This format is
1195 special in that that each image frame consists of three files, for
1196 each of the YUV420P components. To read or write this image file format,
1197 specify the name of the '.Y' file. The muxer will automatically open the
1198 '.U' and '.V' files as required.
1204 If set to 1, expand the filename with pts from pkt->pts.
1208 Start the sequence from the specified number. Default value is 1.
1211 If set to 1, the filename will always be interpreted as just a
1212 filename, not a pattern, and the corresponding file will be continuously
1213 overwritten with new images. Default value is 0.
1216 If set to 1, expand the filename with date and time information from
1217 @code{strftime()}. Default value is 0.
1219 @item protocol_opts @var{options_list}
1220 Set protocol options as a :-separated list of key=value parameters. Values
1221 containing the @code{:} special character must be escaped.
1225 @subsection Examples
1227 The following example shows how to use @command{ffmpeg} for creating a
1228 sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
1229 taking one image every second from the input video:
1231 ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
1234 Note that with @command{ffmpeg}, if the format is not specified with the
1235 @code{-f} option and the output filename specifies an image file
1236 format, the image2 muxer is automatically selected, so the previous
1237 command can be written as:
1239 ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
1242 Note also that the pattern must not necessarily contain "%d" or
1243 "%0@var{N}d", for example to create a single image file
1244 @file{img.jpeg} from the start of the input video you can employ the command:
1246 ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
1249 The @option{strftime} option allows you to expand the filename with
1250 date and time information. Check the documentation of
1251 the @code{strftime()} function for the syntax.
1253 For example to generate image files from the @code{strftime()}
1254 "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
1257 ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
1260 You can set the file name with current frame's PTS:
1262 ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
1265 A more complex example is to publish contents of your desktop directly to a
1266 WebDAV server every second:
1268 ffmpeg -f x11grab -framerate 1 -i :0.0 -q:v 6 -update 1 -protocol_opts method=PUT http://example.com/desktop.jpg
1273 Matroska container muxer.
1275 This muxer implements the matroska and webm container specs.
1277 @subsection Metadata
1279 The recognized metadata settings in this muxer are:
1283 Set title name provided to a single track.
1286 Specify the language of the track in the Matroska languages form.
1288 The language can be either the 3 letters bibliographic ISO-639-2 (ISO
1289 639-2/B) form (like "fre" for French), or a language code mixed with a
1290 country code for specialities in languages (like "fre-ca" for Canadian
1294 Set stereo 3D video layout of two views in a single video track.
1296 The following values are recognized:
1301 Both views are arranged side by side, Left-eye view is on the left
1303 Both views are arranged in top-bottom orientation, Left-eye view is at bottom
1305 Both views are arranged in top-bottom orientation, Left-eye view is on top
1306 @item checkerboard_rl
1307 Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
1308 @item checkerboard_lr
1309 Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
1310 @item row_interleaved_rl
1311 Each view is constituted by a row based interleaving, Right-eye view is first row
1312 @item row_interleaved_lr
1313 Each view is constituted by a row based interleaving, Left-eye view is first row
1314 @item col_interleaved_rl
1315 Both views are arranged in a column based interleaving manner, Right-eye view is first column
1316 @item col_interleaved_lr
1317 Both views are arranged in a column based interleaving manner, Left-eye view is first column
1318 @item anaglyph_cyan_red
1319 All frames are in anaglyph format viewable through red-cyan filters
1321 Both views are arranged side by side, Right-eye view is on the left
1322 @item anaglyph_green_magenta
1323 All frames are in anaglyph format viewable through green-magenta filters
1325 Both eyes laced in one Block, Left-eye view is first
1327 Both eyes laced in one Block, Right-eye view is first
1331 For example a 3D WebM clip can be created using the following command line:
1333 ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
1338 This muxer supports the following options:
1341 @item reserve_index_space
1342 By default, this muxer writes the index for seeking (called cues in Matroska
1343 terms) at the end of the file, because it cannot know in advance how much space
1344 to leave for the index at the beginning of the file. However for some use cases
1345 -- e.g. streaming where seeking is possible but slow -- it is useful to put the
1346 index at the beginning of the file.
1348 If this option is set to a non-zero value, the muxer will reserve a given amount
1349 of space in the file header and then try to write the cues there when the muxing
1350 finishes. If the available space does not suffice, muxing will fail. A safe size
1351 for most use cases should be about 50kB per hour of video.
1353 Note that cues are only written if the output is seekable and this option will
1354 have no effect if it is not.
1362 This is a variant of the @ref{hash} muxer. Unlike that muxer, it
1363 defaults to using the MD5 hash function.
1365 @subsection Examples
1367 To compute the MD5 hash of the input converted to raw
1368 audio and video, and store it in the file @file{out.md5}:
1370 ffmpeg -i INPUT -f md5 out.md5
1373 You can print the MD5 to stdout with the command:
1375 ffmpeg -i INPUT -f md5 -
1378 See also the @ref{hash} and @ref{framemd5} muxers.
1380 @section mov, mp4, ismv
1382 MOV/MP4/ISMV (Smooth Streaming) muxer.
1384 The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
1385 file has all the metadata about all packets stored in one location
1386 (written at the end of the file, it can be moved to the start for
1387 better playback by adding @var{faststart} to the @var{movflags}, or
1388 using the @command{qt-faststart} tool). A fragmented
1389 file consists of a number of fragments, where packets and metadata
1390 about these packets are stored together. Writing a fragmented
1391 file has the advantage that the file is decodable even if the
1392 writing is interrupted (while a normal MOV/MP4 is undecodable if
1393 it is not properly finished), and it requires less memory when writing
1394 very long files (since writing normal MOV/MP4 files stores info about
1395 every single packet in memory until the file is closed). The downside
1396 is that it is less compatible with other applications.
1400 Fragmentation is enabled by setting one of the AVOptions that define
1401 how to cut the file into fragments:
1404 @item -moov_size @var{bytes}
1405 Reserves space for the moov atom at the beginning of the file instead of placing the
1406 moov atom at the end. If the space reserved is insufficient, muxing will fail.
1407 @item -movflags frag_keyframe
1408 Start a new fragment at each video keyframe.
1409 @item -frag_duration @var{duration}
1410 Create fragments that are @var{duration} microseconds long.
1411 @item -frag_size @var{size}
1412 Create fragments that contain up to @var{size} bytes of payload data.
1413 @item -movflags frag_custom
1414 Allow the caller to manually choose when to cut fragments, by
1415 calling @code{av_write_frame(ctx, NULL)} to write a fragment with
1416 the packets written so far. (This is only useful with other
1417 applications integrating libavformat, not from @command{ffmpeg}.)
1418 @item -min_frag_duration @var{duration}
1419 Don't create fragments that are shorter than @var{duration} microseconds long.
1422 If more than one condition is specified, fragments are cut when
1423 one of the specified conditions is fulfilled. The exception to this is
1424 @code{-min_frag_duration}, which has to be fulfilled for any of the other
1425 conditions to apply.
1427 Additionally, the way the output file is written can be adjusted
1428 through a few other options:
1431 @item -movflags empty_moov
1432 Write an initial moov atom directly at the start of the file, without
1433 describing any samples in it. Generally, an mdat/moov pair is written
1434 at the start of the file, as a normal MOV/MP4 file, containing only
1435 a short portion of the file. With this option set, there is no initial
1436 mdat atom, and the moov atom only describes the tracks but has
1439 This option is implicitly set when writing ismv (Smooth Streaming) files.
1440 @item -movflags separate_moof
1441 Write a separate moof (movie fragment) atom for each track. Normally,
1442 packets for all tracks are written in a moof atom (which is slightly
1443 more efficient), but with this option set, the muxer writes one moof/mdat
1444 pair for each track, making it easier to separate tracks.
1446 This option is implicitly set when writing ismv (Smooth Streaming) files.
1447 @item -movflags skip_sidx
1448 Skip writing of sidx atom. When bitrate overhead due to sidx atom is high,
1449 this option could be used for cases where sidx atom is not mandatory.
1450 When global_sidx flag is enabled, this option will be ignored.
1451 @item -movflags faststart
1452 Run a second pass moving the index (moov atom) to the beginning of the file.
1453 This operation can take a while, and will not work in various situations such
1454 as fragmented output, thus it is not enabled by default.
1455 @item -movflags rtphint
1456 Add RTP hinting tracks to the output file.
1457 @item -movflags disable_chpl
1458 Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
1459 and a QuickTime chapter track are written to the file. With this option
1460 set, only the QuickTime chapter track will be written. Nero chapters can
1461 cause failures when the file is reprocessed with certain tagging programs, like
1462 mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
1463 @item -movflags omit_tfhd_offset
1464 Do not write any absolute base_data_offset in tfhd atoms. This avoids
1465 tying fragments to absolute byte positions in the file/streams.
1466 @item -movflags default_base_moof
1467 Similarly to the omit_tfhd_offset, this flag avoids writing the
1468 absolute base_data_offset field in tfhd atoms, but does so by using
1469 the new default-base-is-moof flag instead. This flag is new from
1470 14496-12:2012. This may make the fragments easier to parse in certain
1471 circumstances (avoiding basing track fragment location calculations
1472 on the implicit end of the previous track fragment).
1474 Specify @code{on} to force writing a timecode track, @code{off} to disable it
1475 and @code{auto} to write a timecode track only for mov and mp4 output (default).
1476 @item -movflags negative_cts_offsets
1477 Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
1478 be negative. This enables the initial sample to have DTS/CTS of zero, and
1479 reduces the need for edit lists for some cases such as video tracks with
1480 B-frames. Additionally, eases conformance with the DASH-IF interoperability
1483 This option is implicitly set when writing ismv (Smooth Streaming) files.
1485 Write producer time reference box (PRFT) with a specified time source for the
1486 NTP field in the PRFT box. Set value as @samp{wallclock} to specify timesource
1487 as wallclock time and @samp{pts} to specify timesource as input packets' PTS
1490 Setting value to @samp{pts} is applicable only for a live encoding use case,
1491 where PTS values are set as as wallclock time at the source. For example, an
1492 encoding use case with decklink capture source where @option{video_pts} and
1493 @option{audio_pts} are set to @samp{abs_wallclock}.
1498 Smooth Streaming content can be pushed in real time to a publishing
1499 point on IIS with this muxer. Example:
1501 ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
1504 @subsection Audible AAX
1506 Audible AAX files are encrypted M4B files, and they can be decrypted by specifying a 4 byte activation secret.
1508 ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
1513 The MP3 muxer writes a raw MP3 stream with the following optional features:
1516 An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
1517 2.4 are supported, the @code{id3v2_version} private option controls which one is
1518 used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
1521 The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
1522 The pictures are supplied to the muxer in form of a video stream with a single
1523 packet. There can be any number of those streams, each will correspond to a
1524 single APIC frame. The stream metadata tags @var{title} and @var{comment} map
1525 to APIC @var{description} and @var{picture type} respectively. See
1526 @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
1528 Note that the APIC frames must be written at the beginning, so the muxer will
1529 buffer the audio frames until it gets all the pictures. It is therefore advised
1530 to provide the pictures as soon as possible to avoid excessive buffering.
1533 A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
1534 default, but will be written only if the output is seekable. The
1535 @code{write_xing} private option can be used to disable it. The frame contains
1536 various information that may be useful to the decoder, like the audio duration
1540 A legacy ID3v1 tag at the end of the file (disabled by default). It may be
1541 enabled with the @code{write_id3v1} private option, but as its capabilities are
1542 very limited, its usage is not recommended.
1547 Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
1549 ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
1552 To attach a picture to an mp3 file select both the audio and the picture stream
1555 ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
1556 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
1559 Write a "clean" MP3 without any extra features:
1561 ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
1566 MPEG transport stream muxer.
1568 This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
1570 The recognized metadata settings in mpegts muxer are @code{service_provider}
1571 and @code{service_name}. If they are not set the default for
1572 @code{service_provider} is @samp{FFmpeg} and the default for
1573 @code{service_name} is @samp{Service01}.
1577 The muxer options are:
1580 @item mpegts_transport_stream_id @var{integer}
1581 Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
1582 Default is @code{0x0001}.
1584 @item mpegts_original_network_id @var{integer}
1585 Set the @samp{original_network_id}. This is unique identifier of a
1586 network in DVB. Its main use is in the unique identification of a service
1587 through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
1590 @item mpegts_service_id @var{integer}
1591 Set the @samp{service_id}, also known as program in DVB. Default is
1594 @item mpegts_service_type @var{integer}
1595 Set the program @samp{service_type}. Default is @code{digital_tv}.
1596 Accepts the following options:
1599 Any hexadecimal value between @code{0x01} and @code{0xff} as defined in
1604 Digital Radio service.
1607 @item advanced_codec_digital_radio
1608 Advanced Codec Digital Radio service.
1609 @item mpeg2_digital_hdtv
1610 MPEG2 Digital HDTV service.
1611 @item advanced_codec_digital_sdtv
1612 Advanced Codec Digital SDTV service.
1613 @item advanced_codec_digital_hdtv
1614 Advanced Codec Digital HDTV service.
1617 @item mpegts_pmt_start_pid @var{integer}
1618 Set the first PID for PMTs. Default is @code{0x1000}, minimum is @code{0x0020},
1619 maximum is @code{0x1ffa}.
1621 @item mpegts_start_pid @var{integer}
1622 Set the first PID for elementary streams. Default is @code{0x0100}, minimum is
1623 @code{0x0020}, maximum is @code{0x1ffa}.
1625 @item mpegts_m2ts_mode @var{boolean}
1626 Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
1629 @item muxrate @var{integer}
1630 Set a constant muxrate. Default is VBR.
1632 @item pes_payload_size @var{integer}
1633 Set minimum PES packet payload in bytes. Default is @code{2930}.
1635 @item mpegts_flags @var{flags}
1636 Set mpegts flags. Accepts the following options:
1638 @item resend_headers
1639 Reemit PAT/PMT before writing the next packet.
1641 Use LATM packetization for AAC.
1642 @item pat_pmt_at_frames
1643 Reemit PAT and PMT at each video frame.
1645 Conform to System B (DVB) instead of System A (ATSC).
1646 @item initial_discontinuity
1647 Mark the initial packet of each stream as discontinuity.
1650 @item mpegts_copyts @var{boolean}
1651 Preserve original timestamps, if value is set to @code{1}. Default value
1652 is @code{-1}, which results in shifting timestamps so that they start from 0.
1654 @item omit_video_pes_length @var{boolean}
1655 Omit the PES packet length for video packets. Default is @code{1} (true).
1657 @item pcr_period @var{integer}
1658 Override the default PCR retransmission time in milliseconds. Default is
1659 @code{-1} which means that the PCR interval will be determined automatically:
1660 20 ms is used for CBR streams, the highest multiple of the frame duration which
1661 is less than 100 ms is used for VBR streams.
1663 @item pat_period @var{duration}
1664 Maximum time in seconds between PAT/PMT tables. Default is @code{0.1}.
1666 @item sdt_period @var{duration}
1667 Maximum time in seconds between SDT tables. Default is @code{0.5}.
1669 @item tables_version @var{integer}
1670 Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
1671 This option allows updating stream structure so that standard consumer may
1672 detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
1673 usage) or restart @command{ffmpeg} instance, cyclically changing
1674 @option{tables_version} value:
1677 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1678 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1680 ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
1681 ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
1682 ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
1690 ffmpeg -i file.mpg -c copy \
1691 -mpegts_original_network_id 0x1122 \
1692 -mpegts_transport_stream_id 0x3344 \
1693 -mpegts_service_id 0x5566 \
1694 -mpegts_pmt_start_pid 0x1500 \
1695 -mpegts_start_pid 0x150 \
1696 -metadata service_provider="Some provider" \
1697 -metadata service_name="Some Channel" \
1701 @section mxf, mxf_d10, mxf_opatom
1707 The muxer options are:
1710 @item store_user_comments @var{bool}
1711 Set if user comments should be stored if available or never.
1712 IRT D-10 does not allow user comments. The default is thus to write them for
1713 mxf and mxf_opatom but not for mxf_d10
1720 This muxer does not generate any output file, it is mainly useful for
1721 testing or benchmarking purposes.
1723 For example to benchmark decoding with @command{ffmpeg} you can use the
1726 ffmpeg -benchmark -i INPUT -f null out.null
1729 Note that the above command does not read or write the @file{out.null}
1730 file, but specifying the output file is required by the @command{ffmpeg}
1733 Alternatively you can write the command as:
1735 ffmpeg -benchmark -i INPUT -f null -
1741 @item -syncpoints @var{flags}
1742 Change the syncpoint usage in nut:
1744 @item @var{default} use the normal low-overhead seeking aids.
1745 @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
1746 Use of this option is not recommended, as the resulting files are very damage
1747 sensitive and seeking is not possible. Also in general the overhead from
1748 syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
1749 all growing data tables, allowing to mux endless streams with limited memory
1750 and without these disadvantages.
1751 @item @var{timestamped} extend the syncpoint with a wallclock field.
1753 The @var{none} and @var{timestamped} flags are experimental.
1754 @item -write_index @var{bool}
1755 Write index at the end, the default is to write an index.
1759 ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
1764 Ogg container muxer.
1767 @item -page_duration @var{duration}
1768 Preferred page duration, in microseconds. The muxer will attempt to create
1769 pages that are approximately @var{duration} microseconds long. This allows the
1770 user to compromise between seek granularity and container overhead. The default
1771 is 1 second. A value of 0 will fill all segments, making pages as large as
1772 possible. A value of 1 will effectively use 1 packet-per-page in most
1773 situations, giving a small seek granularity at the cost of additional container
1775 @item -serial_offset @var{value}
1776 Serial value from which to set the streams serial number.
1777 Setting it to different and sufficiently large values ensures that the produced
1778 ogg files can be safely chained.
1783 @section segment, stream_segment, ssegment
1785 Basic stream segmenter.
1787 This muxer outputs streams to a number of separate files of nearly
1788 fixed duration. Output filename pattern can be set in a fashion
1789 similar to @ref{image2}, or by using a @code{strftime} template if
1790 the @option{strftime} option is enabled.
1792 @code{stream_segment} is a variant of the muxer used to write to
1793 streaming output formats, i.e. which do not require global headers,
1794 and is recommended for outputting e.g. to MPEG transport stream segments.
1795 @code{ssegment} is a shorter alias for @code{stream_segment}.
1797 Every segment starts with a keyframe of the selected reference stream,
1798 which is set through the @option{reference_stream} option.
1800 Note that if you want accurate splitting for a video file, you need to
1801 make the input key frames correspond to the exact splitting times
1802 expected by the segmenter, or the segment muxer will start the new
1803 segment with the key frame found next after the specified start
1806 The segment muxer works best with a single constant frame rate video.
1808 Optionally it can generate a list of the created segments, by setting
1809 the option @var{segment_list}. The list type is specified by the
1810 @var{segment_list_type} option. The entry filenames in the segment
1811 list are set by default to the basename of the corresponding segment
1814 See also the @ref{hls} muxer, which provides a more specific
1815 implementation for HLS segmentation.
1819 The segment muxer supports the following options:
1822 @item increment_tc @var{1|0}
1823 if set to @code{1}, increment timecode between each segment
1824 If this is selected, the input need to have
1825 a timecode in the first video stream. Default value is
1828 @item reference_stream @var{specifier}
1829 Set the reference stream, as specified by the string @var{specifier}.
1830 If @var{specifier} is set to @code{auto}, the reference is chosen
1831 automatically. Otherwise it must be a stream specifier (see the ``Stream
1832 specifiers'' chapter in the ffmpeg manual) which specifies the
1833 reference stream. The default value is @code{auto}.
1835 @item segment_format @var{format}
1836 Override the inner container format, by default it is guessed by the filename
1839 @item segment_format_options @var{options_list}
1840 Set output format options using a :-separated list of key=value
1841 parameters. Values containing the @code{:} special character must be
1844 @item segment_list @var{name}
1845 Generate also a listfile named @var{name}. If not specified no
1846 listfile is generated.
1848 @item segment_list_flags @var{flags}
1849 Set flags affecting the segment list generation.
1851 It currently supports the following flags:
1854 Allow caching (only affects M3U8 list files).
1857 Allow live-friendly file generation.
1860 @item segment_list_size @var{size}
1861 Update the list file so that it contains at most @var{size}
1862 segments. If 0 the list file will contain all the segments. Default
1865 @item segment_list_entry_prefix @var{prefix}
1866 Prepend @var{prefix} to each entry. Useful to generate absolute paths.
1867 By default no prefix is applied.
1869 @item segment_list_type @var{type}
1870 Select the listing format.
1872 The following values are recognized:
1875 Generate a flat list for the created segments, one segment per line.
1878 Generate a list for the created segments, one segment per line,
1879 each line matching the format (comma-separated values):
1881 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
1884 @var{segment_filename} is the name of the output file generated by the
1885 muxer according to the provided pattern. CSV escaping (according to
1886 RFC4180) is applied if required.
1888 @var{segment_start_time} and @var{segment_end_time} specify
1889 the segment start and end time expressed in seconds.
1891 A list file with the suffix @code{".csv"} or @code{".ext"} will
1892 auto-select this format.
1894 @samp{ext} is deprecated in favor or @samp{csv}.
1897 Generate an ffconcat file for the created segments. The resulting file
1898 can be read using the FFmpeg @ref{concat} demuxer.
1900 A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
1901 auto-select this format.
1904 Generate an extended M3U8 file, version 3, compliant with
1905 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
1907 A list file with the suffix @code{".m3u8"} will auto-select this format.
1910 If not specified the type is guessed from the list file name suffix.
1912 @item segment_time @var{time}
1913 Set segment duration to @var{time}, the value must be a duration
1914 specification. Default value is "2". See also the
1915 @option{segment_times} option.
1917 Note that splitting may not be accurate, unless you force the
1918 reference stream key-frames at the given time. See the introductory
1919 notice and the examples below.
1921 @item segment_atclocktime @var{1|0}
1922 If set to "1" split at regular clock time intervals starting from 00:00
1923 o'clock. The @var{time} value specified in @option{segment_time} is
1924 used for setting the length of the splitting interval.
1926 For example with @option{segment_time} set to "900" this makes it possible
1927 to create files at 12:00 o'clock, 12:15, 12:30, etc.
1929 Default value is "0".
1931 @item segment_clocktime_offset @var{duration}
1932 Delay the segment splitting times with the specified duration when using
1933 @option{segment_atclocktime}.
1935 For example with @option{segment_time} set to "900" and
1936 @option{segment_clocktime_offset} set to "300" this makes it possible to
1937 create files at 12:05, 12:20, 12:35, etc.
1939 Default value is "0".
1941 @item segment_clocktime_wrap_duration @var{duration}
1942 Force the segmenter to only start a new segment if a packet reaches the muxer
1943 within the specified duration after the segmenting clock time. This way you
1944 can make the segmenter more resilient to backward local time jumps, such as
1945 leap seconds or transition to standard time from daylight savings time.
1947 Default is the maximum possible duration which means starting a new segment
1948 regardless of the elapsed time since the last clock time.
1950 @item segment_time_delta @var{delta}
1951 Specify the accuracy time when selecting the start time for a
1952 segment, expressed as a duration specification. Default value is "0".
1954 When delta is specified a key-frame will start a new segment if its
1955 PTS satisfies the relation:
1957 PTS >= start_time - time_delta
1960 This option is useful when splitting video content, which is always
1961 split at GOP boundaries, in case a key frame is found just before the
1962 specified split time.
1964 In particular may be used in combination with the @file{ffmpeg} option
1965 @var{force_key_frames}. The key frame times specified by
1966 @var{force_key_frames} may not be set accurately because of rounding
1967 issues, with the consequence that a key frame time may result set just
1968 before the specified time. For constant frame rate videos a value of
1969 1/(2*@var{frame_rate}) should address the worst case mismatch between
1970 the specified time and the time set by @var{force_key_frames}.
1972 @item segment_times @var{times}
1973 Specify a list of split points. @var{times} contains a list of comma
1974 separated duration specifications, in increasing order. See also
1975 the @option{segment_time} option.
1977 @item segment_frames @var{frames}
1978 Specify a list of split video frame numbers. @var{frames} contains a
1979 list of comma separated integer numbers, in increasing order.
1981 This option specifies to start a new segment whenever a reference
1982 stream key frame is found and the sequential number (starting from 0)
1983 of the frame is greater or equal to the next value in the list.
1985 @item segment_wrap @var{limit}
1986 Wrap around segment index once it reaches @var{limit}.
1988 @item segment_start_number @var{number}
1989 Set the sequence number of the first segment. Defaults to @code{0}.
1991 @item strftime @var{1|0}
1992 Use the @code{strftime} function to define the name of the new
1993 segments to write. If this is selected, the output segment name must
1994 contain a @code{strftime} function template. Default value is
1997 @item break_non_keyframes @var{1|0}
1998 If enabled, allow segments to start on frames other than keyframes. This
1999 improves behavior on some players when the time between keyframes is
2000 inconsistent, but may make things worse on others, and can cause some oddities
2001 during seeking. Defaults to @code{0}.
2003 @item reset_timestamps @var{1|0}
2004 Reset timestamps at the beginning of each segment, so that each segment
2005 will start with near-zero timestamps. It is meant to ease the playback
2006 of the generated segments. May not work with some combinations of
2007 muxers/codecs. It is set to @code{0} by default.
2009 @item initial_offset @var{offset}
2010 Specify timestamp offset to apply to the output packet timestamps. The
2011 argument must be a time duration specification, and defaults to 0.
2013 @item write_empty_segments @var{1|0}
2014 If enabled, write an empty segment if there are no packets during the period a
2015 segment would usually span. Otherwise, the segment will be filled with the next
2016 packet written. Defaults to @code{0}.
2019 Make sure to require a closed GOP when encoding and to set the GOP
2020 size to fit your segment time constraint.
2022 @subsection Examples
2026 Remux the content of file @file{in.mkv} to a list of segments
2027 @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
2028 generated segments to @file{out.list}:
2030 ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
2034 Segment input and set output format options for the output segments:
2036 ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
2040 Segment the input file according to the split points specified by the
2041 @var{segment_times} option:
2043 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
2047 Use the @command{ffmpeg} @option{force_key_frames}
2048 option to force key frames in the input at the specified location, together
2049 with the segment option @option{segment_time_delta} to account for
2050 possible roundings operated when setting key frame times.
2052 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
2053 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
2055 In order to force key frames on the input file, transcoding is
2059 Segment the input file by splitting the input file according to the
2060 frame numbers sequence specified with the @option{segment_frames} option:
2062 ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
2066 Convert the @file{in.mkv} to TS segments using the @code{libx264}
2067 and @code{aac} encoders:
2069 ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
2073 Segment the input file, and create an M3U8 live playlist (can be used
2074 as live HLS source):
2076 ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
2077 -segment_list_flags +live -segment_time 10 out%03d.mkv
2081 @section smoothstreaming
2083 Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
2087 Specify the number of fragments kept in the manifest. Default 0 (keep all).
2089 @item extra_window_size
2090 Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
2092 @item lookahead_count
2093 Specify the number of lookahead fragments. Default 2.
2095 @item min_frag_duration
2096 Specify the minimum fragment duration (in microseconds). Default 5000000.
2098 @item remove_at_exit
2099 Specify whether to remove all fragments when finished. Default 0 (do not remove).
2106 Per stream hash testing format.
2108 This muxer computes and prints a cryptographic hash of all the input frames,
2109 on a per-stream basis. This can be used for equality checks without having
2110 to do a complete binary comparison.
2112 By default audio frames are converted to signed 16-bit raw audio and
2113 video frames to raw video before computing the hash, but the output
2114 of explicit conversions to other codecs can also be used. Timestamps
2115 are ignored. It uses the SHA-256 cryptographic hash function by default,
2116 but supports several other algorithms.
2118 The output of the muxer consists of one line per stream of the form:
2119 @var{streamindex},@var{streamtype},@var{algo}=@var{hash}, where
2120 @var{streamindex} is the index of the mapped stream, @var{streamtype} is a
2121 single character indicating the type of stream, @var{algo} is a short string
2122 representing the hash function used, and @var{hash} is a hexadecimal number
2123 representing the computed hash.
2126 @item hash @var{algorithm}
2127 Use the cryptographic hash function specified by the string @var{algorithm}.
2128 Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
2129 @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
2130 @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
2131 @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
2135 @subsection Examples
2137 To compute the SHA-256 hash of the input converted to raw audio and
2138 video, and store it in the file @file{out.sha256}:
2140 ffmpeg -i INPUT -f streamhash out.sha256
2143 To print an MD5 hash to stdout use the command:
2145 ffmpeg -i INPUT -f streamhash -hash md5 -
2148 See also the @ref{hash} and @ref{framehash} muxers.
2153 The fifo pseudo-muxer allows the separation of encoding and muxing by using
2154 first-in-first-out queue and running the actual muxer in a separate thread. This
2155 is especially useful in combination with the @ref{tee} muxer and can be used to
2156 send data to several destinations with different reliability/writing speed/latency.
2158 API users should be aware that callback functions (interrupt_callback,
2159 io_open and io_close) used within its AVFormatContext must be thread-safe.
2161 The behavior of the fifo muxer if the queue fills up or if the output fails is
2167 output can be transparently restarted with configurable delay between retries
2168 based on real time or time of the processed stream.
2171 encoding can be blocked during temporary failure, or continue transparently
2172 dropping packets in case fifo queue fills up.
2179 Specify the format name. Useful if it cannot be guessed from the
2183 Specify size of the queue (number of packets). Default value is 60.
2186 Specify format options for the underlying muxer. Muxer options can be specified
2187 as a list of @var{key}=@var{value} pairs separated by ':'.
2189 @item drop_pkts_on_overflow @var{bool}
2190 If set to 1 (true), in case the fifo queue fills up, packets will be dropped
2191 rather than blocking the encoder. This makes it possible to continue streaming without
2192 delaying the input, at the cost of omitting part of the stream. By default
2193 this option is set to 0 (false), so in such cases the encoder will be blocked
2194 until the muxer processes some of the packets and none of them is lost.
2196 @item attempt_recovery @var{bool}
2197 If failure occurs, attempt to recover the output. This is especially useful
2198 when used with network output, since it makes it possible to restart streaming transparently.
2199 By default this option is set to 0 (false).
2201 @item max_recovery_attempts
2202 Sets maximum number of successive unsuccessful recovery attempts after which
2203 the output fails permanently. By default this option is set to 0 (unlimited).
2205 @item recovery_wait_time @var{duration}
2206 Waiting time before the next recovery attempt after previous unsuccessful
2207 recovery attempt. Default value is 5 seconds.
2209 @item recovery_wait_streamtime @var{bool}
2210 If set to 0 (false), the real time is used when waiting for the recovery
2211 attempt (i.e. the recovery will be attempted after at least
2212 recovery_wait_time seconds).
2213 If set to 1 (true), the time of the processed stream is taken into account
2214 instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
2215 seconds of the stream is omitted).
2216 By default, this option is set to 0 (false).
2218 @item recover_any_error @var{bool}
2219 If set to 1 (true), recovery will be attempted regardless of type of the error
2220 causing the failure. By default this option is set to 0 (false) and in case of
2221 certain (usually permanent) errors the recovery is not attempted even when
2222 @var{attempt_recovery} is set to 1.
2224 @item restart_with_keyframe @var{bool}
2225 Specify whether to wait for the keyframe after recovering from
2226 queue overflow or failure. This option is set to 0 (false) by default.
2230 @subsection Examples
2235 Stream something to rtmp server, continue processing the stream at real-time
2236 rate even in case of temporary failure (network outage) and attempt to recover
2237 streaming every second indefinitely.
2239 ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
2240 -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
2248 The tee muxer can be used to write the same data to several outputs, such as files or streams.
2249 It can be used, for example, to stream a video over a network and save it to disk at the same time.
2251 It is different from specifying several outputs to the @command{ffmpeg}
2252 command-line tool. With the tee muxer, the audio and video data will be encoded only once.
2253 With conventional multiple outputs, multiple encoding operations in parallel are initiated,
2254 which can be a very expensive process. The tee muxer is not useful when using the libavformat API
2255 directly because it is then possible to feed the same packets to several muxers directly.
2257 Since the tee muxer does not represent any particular output format, ffmpeg cannot auto-select
2258 output streams. So all streams intended for output must be specified using @code{-map}. See
2261 Some encoders may need different options depending on the output format;
2262 the auto-detection of this can not work with the tee muxer, so they need to be explicitly specified.
2263 The main example is the @option{global_header} flag.
2265 The slave outputs are specified in the file name given to the muxer,
2266 separated by '|'. If any of the slave name contains the '|' separator,
2267 leading or trailing spaces or any special character, those must be
2268 escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
2269 section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
2275 @item use_fifo @var{bool}
2276 If set to 1, slave outputs will be processed in separate threads using the @ref{fifo}
2277 muxer. This allows to compensate for different speed/latency/reliability of
2278 outputs and setup transparent recovery. By default this feature is turned off.
2281 Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
2285 Muxer options can be specified for each slave by prepending them as a list of
2286 @var{key}=@var{value} pairs separated by ':', between square brackets. If
2287 the options values contain a special character or the ':' separator, they
2288 must be escaped; note that this is a second level escaping.
2290 The following special options are also recognized:
2293 Specify the format name. Required if it cannot be guessed from the
2296 @item bsfs[/@var{spec}]
2297 Specify a list of bitstream filters to apply to the specified
2300 It is possible to specify to which streams a given bitstream filter
2301 applies, by appending a stream specifier to the option separated by
2302 @code{/}. @var{spec} must be a stream specifier (see @ref{Format
2303 stream specifiers}).
2305 If the stream specifier is not specified, the bitstream filters will be
2306 applied to all streams in the output. This will cause that output operation
2307 to fail if the output contains streams to which the bitstream filter cannot
2308 be applied e.g. @code{h264_mp4toannexb} being applied to an output containing an audio stream.
2310 Options for a bitstream filter must be specified in the form of @code{opt=value}.
2312 Several bitstream filters can be specified, separated by ",".
2314 @item use_fifo @var{bool}
2315 This allows to override tee muxer use_fifo option for individual slave muxer.
2318 This allows to override tee muxer fifo_options for individual slave muxer.
2322 Select the streams that should be mapped to the slave output,
2323 specified by a stream specifier. If not specified, this defaults to
2324 all the mapped streams. This will cause that output operation to fail
2325 if the output format does not accept all mapped streams.
2327 You may use multiple stream specifiers separated by commas (@code{,}) e.g.: @code{a:0,v}
2330 Specify behaviour on output failure. This can be set to either @code{abort} (which is
2331 default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
2332 on this slave output. @code{ignore} will ignore failure on this output, so other outputs
2333 will continue without being affected.
2336 @subsection Examples
2340 Encode something and both archive it in a WebM file and stream it
2341 as MPEG-TS over UDP:
2343 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2344 "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2348 As above, but continue streaming even if output to local file fails
2349 (for example local drive fills up):
2351 ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
2352 "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
2356 Use @command{ffmpeg} to encode the input, and send the output
2357 to three different destinations. The @code{dump_extra} bitstream
2358 filter is used to add extradata information to all the output video
2359 keyframes packets, as requested by the MPEG-TS format. The select
2360 option is applied to @file{out.aac} in order to make it contain only
2363 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2364 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
2368 As above, but select only stream @code{a:1} for the audio output. Note
2369 that a second level escaping must be performed, as ":" is a special
2370 character used to separate options.
2372 ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
2373 -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
2377 @section webm_dash_manifest
2379 WebM DASH Manifest muxer.
2381 This muxer implements the WebM DASH Manifest specification to generate the DASH
2382 manifest XML. It also supports manifest generation for DASH live streams.
2384 For more information see:
2388 WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
2390 ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
2395 This muxer supports the following options:
2398 @item adaptation_sets
2399 This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
2400 unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
2401 audio and video streams. Any number of adaptation sets can be added using this option.
2404 Set this to 1 to create a live stream DASH Manifest. Default: 0.
2406 @item chunk_start_index
2407 Start index of the first chunk. This will go in the @samp{startNumber} attribute
2408 of the @samp{SegmentTemplate} element in the manifest. Default: 0.
2410 @item chunk_duration_ms
2411 Duration of each chunk in milliseconds. This will go in the @samp{duration}
2412 attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
2414 @item utc_timing_url
2415 URL of the page that will return the UTC timestamp in ISO format. This will go
2416 in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
2419 @item time_shift_buffer_depth
2420 Smallest time (in seconds) shifting buffer for which any Representation is
2421 guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
2422 attribute of the @samp{MPD} element. Default: 60.
2424 @item minimum_update_period
2425 Minimum update period (in seconds) of the manifest. This will go in the
2426 @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
2432 ffmpeg -f webm_dash_manifest -i video1.webm \
2433 -f webm_dash_manifest -i video2.webm \
2434 -f webm_dash_manifest -i audio1.webm \
2435 -f webm_dash_manifest -i audio2.webm \
2436 -map 0 -map 1 -map 2 -map 3 \
2438 -f webm_dash_manifest \
2439 -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
2445 WebM Live Chunk Muxer.
2447 This muxer writes out WebM headers and chunks as separate files which can be
2448 consumed by clients that support WebM Live streams via DASH.
2452 This muxer supports the following options:
2455 @item chunk_start_index
2456 Index of the first chunk (defaults to 0).
2459 Filename of the header where the initialization data will be written.
2461 @item audio_chunk_duration
2462 Duration of each audio chunk in milliseconds (defaults to 5000).
2467 ffmpeg -f v4l2 -i /dev/video0 \
2471 -s 640x360 -keyint_min 30 -g 30 \
2473 -header webm_live_video_360.hdr \
2474 -chunk_start_index 1 \
2475 webm_live_video_360_%d.chk \
2480 -header webm_live_audio_128.hdr \
2481 -chunk_start_index 1 \
2482 -audio_chunk_duration 1000 \
2483 webm_live_audio_128_%d.chk