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  1. @chapter Muxers
  2. @c man begin MUXERS
  3. Muxers are configured elements in FFmpeg which allow writing
  4. multimedia streams to a particular type of file.
  5. When you configure your FFmpeg build, all the supported muxers
  6. are enabled by default. You can list all available muxers using the
  7. configure option @code{--list-muxers}.
  8. You can disable all the muxers with the configure option
  9. @code{--disable-muxers} and selectively enable / disable single muxers
  10. with the options @code{--enable-muxer=@var{MUXER}} /
  11. @code{--disable-muxer=@var{MUXER}}.
  12. The option @code{-muxers} of the ff* tools will display the list of
  13. enabled muxers. Use @code{-formats} to view a combined list of
  14. enabled demuxers and muxers.
  15. A description of some of the currently available muxers follows.
  16. @anchor{aiff}
  17. @section aiff
  18. Audio Interchange File Format muxer.
  19. @subsection Options
  20. It accepts the following options:
  21. @table @option
  22. @item write_id3v2
  23. Enable ID3v2 tags writing when set to 1. Default is 0 (disabled).
  24. @item id3v2_version
  25. Select ID3v2 version to write. Currently only version 3 and 4 (aka.
  26. ID3v2.3 and ID3v2.4) are supported. The default is version 4.
  27. @end table
  28. @anchor{asf}
  29. @section asf
  30. Advanced Systems Format muxer.
  31. Note that Windows Media Audio (wma) and Windows Media Video (wmv) use this
  32. muxer too.
  33. @subsection Options
  34. It accepts the following options:
  35. @table @option
  36. @item packet_size
  37. Set the muxer packet size. By tuning this setting you may reduce data
  38. fragmentation or muxer overhead depending on your source. Default value is
  39. 3200, minimum is 100, maximum is 64k.
  40. @end table
  41. @anchor{avi}
  42. @section avi
  43. Audio Video Interleaved muxer.
  44. @subsection Options
  45. It accepts the following options:
  46. @table @option
  47. @item reserve_index_space
  48. Reserve the specified amount of bytes for the OpenDML master index of each
  49. stream within the file header. By default additional master indexes are
  50. embedded within the data packets if there is no space left in the first master
  51. index and are linked together as a chain of indexes. This index structure can
  52. cause problems for some use cases, e.g. third-party software strictly relying
  53. on the OpenDML index specification or when file seeking is slow. Reserving
  54. enough index space in the file header avoids these problems.
  55. The required index space depends on the output file size and should be about 16
  56. bytes per gigabyte. When this option is omitted or set to zero the necessary
  57. index space is guessed.
  58. @item write_channel_mask
  59. Write the channel layout mask into the audio stream header.
  60. This option is enabled by default. Disabling the channel mask can be useful in
  61. specific scenarios, e.g. when merging multiple audio streams into one for
  62. compatibility with software that only supports a single audio stream in AVI
  63. (see @ref{amerge,,the "amerge" section in the ffmpeg-filters manual,ffmpeg-filters}).
  64. @end table
  65. @anchor{chromaprint}
  66. @section chromaprint
  67. Chromaprint fingerprinter.
  68. This muxer feeds audio data to the Chromaprint library,
  69. which generates a fingerprint for the provided audio data. See @url{https://acoustid.org/chromaprint}
  70. It takes a single signed native-endian 16-bit raw audio stream of at most 2 channels.
  71. @subsection Options
  72. @table @option
  73. @item silence_threshold
  74. Threshold for detecting silence, ranges from -1 to 32767. -1 disables silence detection and
  75. is required for use with the AcoustID service. Default is -1.
  76. @item algorithm
  77. Version of algorithm to fingerprint with. Range is 0 to 4. Version 2 requires that silence
  78. detection be enabled. Default is 1.
  79. @item fp_format
  80. Format to output the fingerprint as. Accepts the following options:
  81. @table @samp
  82. @item raw
  83. Binary raw fingerprint
  84. @item compressed
  85. Binary compressed fingerprint
  86. @item base64
  87. Base64 compressed fingerprint @emph{(default)}
  88. @end table
  89. @end table
  90. @anchor{crc}
  91. @section crc
  92. CRC (Cyclic Redundancy Check) testing format.
  93. This muxer computes and prints the Adler-32 CRC of all the input audio
  94. and video frames. By default audio frames are converted to signed
  95. 16-bit raw audio and video frames to raw video before computing the
  96. CRC.
  97. The output of the muxer consists of a single line of the form:
  98. CRC=0x@var{CRC}, where @var{CRC} is a hexadecimal number 0-padded to
  99. 8 digits containing the CRC for all the decoded input frames.
  100. See also the @ref{framecrc} muxer.
  101. @subsection Examples
  102. For example to compute the CRC of the input, and store it in the file
  103. @file{out.crc}:
  104. @example
  105. ffmpeg -i INPUT -f crc out.crc
  106. @end example
  107. You can print the CRC to stdout with the command:
  108. @example
  109. ffmpeg -i INPUT -f crc -
  110. @end example
  111. You can select the output format of each frame with @command{ffmpeg} by
  112. specifying the audio and video codec and format. For example to
  113. compute the CRC of the input audio converted to PCM unsigned 8-bit
  114. and the input video converted to MPEG-2 video, use the command:
  115. @example
  116. ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f crc -
  117. @end example
  118. @section flv
  119. Adobe Flash Video Format muxer.
  120. This muxer accepts the following options:
  121. @table @option
  122. @item flvflags @var{flags}
  123. Possible values:
  124. @table @samp
  125. @item aac_seq_header_detect
  126. Place AAC sequence header based on audio stream data.
  127. @item no_sequence_end
  128. Disable sequence end tag.
  129. @item no_metadata
  130. Disable metadata tag.
  131. @item no_duration_filesize
  132. Disable duration and filesize in metadata when they are equal to zero
  133. at the end of stream. (Be used to non-seekable living stream).
  134. @item add_keyframe_index
  135. Used to facilitate seeking; particularly for HTTP pseudo streaming.
  136. @end table
  137. @end table
  138. @anchor{dash}
  139. @section dash
  140. Dynamic Adaptive Streaming over HTTP (DASH) muxer that creates segments
  141. and manifest files according to the MPEG-DASH standard ISO/IEC 23009-1:2014.
  142. For more information see:
  143. @itemize @bullet
  144. @item
  145. ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
  146. @item
  147. WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
  148. @end itemize
  149. It creates a MPD manifest file and segment files for each stream.
  150. The segment filename might contain pre-defined identifiers used with SegmentTemplate
  151. as defined in section 5.3.9.4.4 of the standard. Available identifiers are "$RepresentationID$",
  152. "$Number$", "$Bandwidth$" and "$Time$".
  153. In addition to the standard identifiers, an ffmpeg-specific "$ext$" identifier is also supported.
  154. When specified ffmpeg will replace $ext$ in the file name with muxing format's extensions such as mp4, webm etc.,
  155. @example
  156. ffmpeg -re -i <input> -map 0 -map 0 -c:a libfdk_aac -c:v libx264
  157. -b:v:0 800k -b:v:1 300k -s:v:1 320x170 -profile:v:1 baseline
  158. -profile:v:0 main -bf 1 -keyint_min 120 -g 120 -sc_threshold 0
  159. -b_strategy 0 -ar:a:1 22050 -use_timeline 1 -use_template 1
  160. -window_size 5 -adaptation_sets "id=0,streams=v id=1,streams=a"
  161. -f dash /path/to/out.mpd
  162. @end example
  163. @table @option
  164. @item -min_seg_duration @var{microseconds}
  165. This is a deprecated option to set the segment length in microseconds, use @var{seg_duration} instead.
  166. @item -seg_duration @var{duration}
  167. Set the segment length in seconds (fractional value can be set). The value is
  168. treated as average segment duration when @var{use_template} is enabled and
  169. @var{use_timeline} is disabled and as minimum segment duration for all the other
  170. use cases.
  171. @item -window_size @var{size}
  172. Set the maximum number of segments kept in the manifest.
  173. @item -extra_window_size @var{size}
  174. Set the maximum number of segments kept outside of the manifest before removing from disk.
  175. @item -remove_at_exit @var{remove}
  176. Enable (1) or disable (0) removal of all segments when finished.
  177. @item -use_template @var{template}
  178. Enable (1) or disable (0) use of SegmentTemplate instead of SegmentList.
  179. @item -use_timeline @var{timeline}
  180. Enable (1) or disable (0) use of SegmentTimeline in SegmentTemplate.
  181. @item -single_file @var{single_file}
  182. Enable (1) or disable (0) storing all segments in one file, accessed using byte ranges.
  183. @item -single_file_name @var{file_name}
  184. 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.
  185. @item -init_seg_name @var{init_name}
  186. 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.
  187. @item -media_seg_name @var{segment_name}
  188. 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.
  189. @item -utc_timing_url @var{utc_url}
  190. URL of the page that will return the UTC timestamp in ISO format. Example: "https://time.akamai.com/?iso"
  191. @item method @var{method}
  192. Use the given HTTP method to create output files. Generally set to PUT or POST.
  193. @item -http_user_agent @var{user_agent}
  194. Override User-Agent field in HTTP header. Applicable only for HTTP output.
  195. @item -http_persistent @var{http_persistent}
  196. Use persistent HTTP connections. Applicable only for HTTP output.
  197. @item -hls_playlist @var{hls_playlist}
  198. Generate HLS playlist files as well. The master playlist is generated with the filename master.m3u8.
  199. One media playlist file is generated for each stream with filenames media_0.m3u8, media_1.m3u8, etc.
  200. @item -streaming @var{streaming}
  201. Enable (1) or disable (0) chunk streaming mode of output. In chunk streaming
  202. mode, each frame will be a moof fragment which forms a chunk.
  203. @item -adaptation_sets @var{adaptation_sets}
  204. Assign streams to AdaptationSets. Syntax is "id=x,streams=a,b,c id=y,streams=d,e" with x and y being the IDs
  205. of the adaptation sets and a,b,c,d and e are the indices of the mapped streams.
  206. To map all video (or audio) streams to an AdaptationSet, "v" (or "a") can be used as stream identifier instead of IDs.
  207. When no assignment is defined, this defaults to an AdaptationSet for each stream.
  208. @item -timeout @var{timeout}
  209. Set timeout for socket I/O operations. Applicable only for HTTP output.
  210. @item -index_correction @var{index_correction}
  211. Enable (1) or Disable (0) segment index correction logic. Applicable only when
  212. @var{use_template} is enabled and @var{use_timeline} is disabled.
  213. When enabled, the logic monitors the flow of segment indexes. If a streams's
  214. segment index value is not at the expected real time position, then the logic
  215. corrects that index value.
  216. Typically this logic is needed in live streaming use cases. The network bandwidth
  217. fluctuations are common during long run streaming. Each fluctuation can cause
  218. the segment indexes fall behind the expected real time position.
  219. @item -format_options @var{options_list}
  220. Set container format (mp4/webm) options using a @code{:} separated list of
  221. key=value parameters. Values containing @code{:} special characters must be
  222. escaped.
  223. @item -global_sidx @var{global_sidx}
  224. Write global SIDX atom. Applicable only for single file, mp4 output, non-streaming mode.
  225. @item -dash_segment_type @var{dash_segment_type}
  226. Possible values:
  227. @item auto
  228. If this flag is set, the dash segment files format will be selected based on the stream codec. This is the default mode.
  229. @item mp4
  230. If this flag is set, the dash segment files will be in in ISOBMFF format.
  231. @item webm
  232. If this flag is set, the dash segment files will be in in WebM format.
  233. @item -ignore_io_errors @var{ignore_io_errors}
  234. Ignore IO errors during open and write. Useful for long-duration runs with network output.
  235. @item -lhls @var{lhls}
  236. Enable Low-latency HLS(LHLS). Adds #EXT-X-PREFETCH tag with current segment's URI.
  237. Apple doesn't have an official spec for LHLS. Meanwhile hls.js player folks are
  238. 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
  239. This option will also try to comply with the above open spec, till Apple's spec officially supports it.
  240. Applicable only when @var{streaming} and @var{hls_playlist} options are enabled.
  241. This is an experimental feature.
  242. @item -master_m3u8_publish_rate @var{master_m3u8_publish_rate}
  243. Publish master playlist repeatedly every after specified number of segment intervals.
  244. @end table
  245. @anchor{framecrc}
  246. @section framecrc
  247. Per-packet CRC (Cyclic Redundancy Check) testing format.
  248. This muxer computes and prints the Adler-32 CRC for each audio
  249. and video packet. By default audio frames are converted to signed
  250. 16-bit raw audio and video frames to raw video before computing the
  251. CRC.
  252. The output of the muxer consists of a line for each audio and video
  253. packet of the form:
  254. @example
  255. @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, 0x@var{CRC}
  256. @end example
  257. @var{CRC} is a hexadecimal number 0-padded to 8 digits containing the
  258. CRC of the packet.
  259. @subsection Examples
  260. For example to compute the CRC of the audio and video frames in
  261. @file{INPUT}, converted to raw audio and video packets, and store it
  262. in the file @file{out.crc}:
  263. @example
  264. ffmpeg -i INPUT -f framecrc out.crc
  265. @end example
  266. To print the information to stdout, use the command:
  267. @example
  268. ffmpeg -i INPUT -f framecrc -
  269. @end example
  270. With @command{ffmpeg}, you can select the output format to which the
  271. audio and video frames are encoded before computing the CRC for each
  272. packet by specifying the audio and video codec. For example, to
  273. compute the CRC of each decoded input audio frame converted to PCM
  274. unsigned 8-bit and of each decoded input video frame converted to
  275. MPEG-2 video, use the command:
  276. @example
  277. ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
  278. @end example
  279. See also the @ref{crc} muxer.
  280. @anchor{framehash}
  281. @section framehash
  282. Per-packet hash testing format.
  283. This muxer computes and prints a cryptographic hash for each audio
  284. and video packet. This can be used for packet-by-packet equality
  285. checks without having to individually do a binary comparison on each.
  286. By default audio frames are converted to signed 16-bit raw audio and
  287. video frames to raw video before computing the hash, but the output
  288. of explicit conversions to other codecs can also be used. It uses the
  289. SHA-256 cryptographic hash function by default, but supports several
  290. other algorithms.
  291. The output of the muxer consists of a line for each audio and video
  292. packet of the form:
  293. @example
  294. @var{stream_index}, @var{packet_dts}, @var{packet_pts}, @var{packet_duration}, @var{packet_size}, @var{hash}
  295. @end example
  296. @var{hash} is a hexadecimal number representing the computed hash
  297. for the packet.
  298. @table @option
  299. @item hash @var{algorithm}
  300. Use the cryptographic hash function specified by the string @var{algorithm}.
  301. Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
  302. @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
  303. @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
  304. @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
  305. @end table
  306. @subsection Examples
  307. To compute the SHA-256 hash of the audio and video frames in @file{INPUT},
  308. converted to raw audio and video packets, and store it in the file
  309. @file{out.sha256}:
  310. @example
  311. ffmpeg -i INPUT -f framehash out.sha256
  312. @end example
  313. To print the information to stdout, using the MD5 hash function, use
  314. the command:
  315. @example
  316. ffmpeg -i INPUT -f framehash -hash md5 -
  317. @end example
  318. See also the @ref{hash} muxer.
  319. @anchor{framemd5}
  320. @section framemd5
  321. Per-packet MD5 testing format.
  322. This is a variant of the @ref{framehash} muxer. Unlike that muxer,
  323. it defaults to using the MD5 hash function.
  324. @subsection Examples
  325. To compute the MD5 hash of the audio and video frames in @file{INPUT},
  326. converted to raw audio and video packets, and store it in the file
  327. @file{out.md5}:
  328. @example
  329. ffmpeg -i INPUT -f framemd5 out.md5
  330. @end example
  331. To print the information to stdout, use the command:
  332. @example
  333. ffmpeg -i INPUT -f framemd5 -
  334. @end example
  335. See also the @ref{framehash} and @ref{md5} muxers.
  336. @anchor{gif}
  337. @section gif
  338. Animated GIF muxer.
  339. It accepts the following options:
  340. @table @option
  341. @item loop
  342. Set the number of times to loop the output. Use @code{-1} for no loop, @code{0}
  343. for looping indefinitely (default).
  344. @item final_delay
  345. Force the delay (expressed in centiseconds) after the last frame. Each frame
  346. ends with a delay until the next frame. The default is @code{-1}, which is a
  347. special value to tell the muxer to re-use the previous delay. In case of a
  348. loop, you might want to customize this value to mark a pause for instance.
  349. @end table
  350. For example, to encode a gif looping 10 times, with a 5 seconds delay between
  351. the loops:
  352. @example
  353. ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
  354. @end example
  355. Note 1: if you wish to extract the frames into separate GIF files, you need to
  356. force the @ref{image2} muxer:
  357. @example
  358. ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
  359. @end example
  360. Note 2: the GIF format has a very large time base: the delay between two frames
  361. can therefore not be smaller than one centi second.
  362. @anchor{hash}
  363. @section hash
  364. Hash testing format.
  365. This muxer computes and prints a cryptographic hash of all the input
  366. audio and video frames. This can be used for equality checks without
  367. having to do a complete binary comparison.
  368. By default audio frames are converted to signed 16-bit raw audio and
  369. video frames to raw video before computing the hash, but the output
  370. of explicit conversions to other codecs can also be used. Timestamps
  371. are ignored. It uses the SHA-256 cryptographic hash function by default,
  372. but supports several other algorithms.
  373. The output of the muxer consists of a single line of the form:
  374. @var{algo}=@var{hash}, where @var{algo} is a short string representing
  375. the hash function used, and @var{hash} is a hexadecimal number
  376. representing the computed hash.
  377. @table @option
  378. @item hash @var{algorithm}
  379. Use the cryptographic hash function specified by the string @var{algorithm}.
  380. Supported values include @code{MD5}, @code{murmur3}, @code{RIPEMD128},
  381. @code{RIPEMD160}, @code{RIPEMD256}, @code{RIPEMD320}, @code{SHA160},
  382. @code{SHA224}, @code{SHA256} (default), @code{SHA512/224}, @code{SHA512/256},
  383. @code{SHA384}, @code{SHA512}, @code{CRC32} and @code{adler32}.
  384. @end table
  385. @subsection Examples
  386. To compute the SHA-256 hash of the input converted to raw audio and
  387. video, and store it in the file @file{out.sha256}:
  388. @example
  389. ffmpeg -i INPUT -f hash out.sha256
  390. @end example
  391. To print an MD5 hash to stdout use the command:
  392. @example
  393. ffmpeg -i INPUT -f hash -hash md5 -
  394. @end example
  395. See also the @ref{framehash} muxer.
  396. @anchor{hls}
  397. @section hls
  398. Apple HTTP Live Streaming muxer that segments MPEG-TS according to
  399. the HTTP Live Streaming (HLS) specification.
  400. It creates a playlist file, and one or more segment files. The output filename
  401. specifies the playlist filename.
  402. By default, the muxer creates a file for each segment produced. These files
  403. have the same name as the playlist, followed by a sequential number and a
  404. .ts extension.
  405. Make sure to require a closed GOP when encoding and to set the GOP
  406. size to fit your segment time constraint.
  407. For example, to convert an input file with @command{ffmpeg}:
  408. @example
  409. ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
  410. @end example
  411. This example will produce the playlist, @file{out.m3u8}, and segment files:
  412. @file{out0.ts}, @file{out1.ts}, @file{out2.ts}, etc.
  413. See also the @ref{segment} muxer, which provides a more generic and
  414. flexible implementation of a segmenter, and can be used to perform HLS
  415. segmentation.
  416. @subsection Options
  417. This muxer supports the following options:
  418. @table @option
  419. @item hls_init_time @var{seconds}
  420. Set the initial target segment length in seconds. Default value is @var{0}.
  421. Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
  422. After the initial playlist is filled @command{ffmpeg} will cut segments
  423. at duration equal to @code{hls_time}
  424. @item hls_time @var{seconds}
  425. Set the target segment length in seconds. Default value is 2.
  426. Segment will be cut on the next key frame after this time has passed.
  427. @item hls_list_size @var{size}
  428. Set the maximum number of playlist entries. If set to 0 the list file
  429. will contain all the segments. Default value is 5.
  430. @item hls_delete_threshold @var{size}
  431. Set the number of unreferenced segments to keep on disk before @code{hls_flags delete_segments}
  432. deletes them. Increase this to allow continue clients to download segments which
  433. were recently referenced in the playlist. Default value is 1, meaning segments older than
  434. @code{hls_list_size+1} will be deleted.
  435. @item hls_ts_options @var{options_list}
  436. Set output format options using a :-separated list of key=value
  437. parameters. Values containing @code{:} special characters must be
  438. escaped.
  439. @item hls_wrap @var{wrap}
  440. This is a deprecated option, you can use @code{hls_list_size}
  441. and @code{hls_flags delete_segments} instead it
  442. This option is useful to avoid to fill the disk with many segment
  443. files, and limits the maximum number of segment files written to disk
  444. to @var{wrap}.
  445. @item hls_start_number_source
  446. Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) according to the specified source.
  447. Unless @code{hls_flags single_file} is set, it also specifies source of starting sequence numbers of
  448. segment and subtitle filenames. In any case, if @code{hls_flags append_list}
  449. is set and read playlist sequence number is greater than the specified start sequence number,
  450. then that value will be used as start value.
  451. It accepts the following values:
  452. @table @option
  453. @item generic (default)
  454. Set the starting sequence numbers according to @var{start_number} option value.
  455. @item epoch
  456. The start number will be the seconds since epoch (1970-01-01 00:00:00)
  457. @item datetime
  458. The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
  459. @end table
  460. @item start_number @var{number}
  461. Start the playlist sequence number (@code{#EXT-X-MEDIA-SEQUENCE}) from the specified @var{number}
  462. when @var{hls_start_number_source} value is @var{generic}. (This is the default case.)
  463. Unless @code{hls_flags single_file} is set, it also specifies starting sequence numbers of segment and subtitle filenames.
  464. Default value is 0.
  465. @item hls_allow_cache @var{allowcache}
  466. Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
  467. @item hls_base_url @var{baseurl}
  468. Append @var{baseurl} to every entry in the playlist.
  469. Useful to generate playlists with absolute paths.
  470. Note that the playlist sequence number must be unique for each segment
  471. and it is not to be confused with the segment filename sequence number
  472. which can be cyclic, for example if the @option{wrap} option is
  473. specified.
  474. @item hls_segment_filename @var{filename}
  475. Set the segment filename. Unless @code{hls_flags single_file} is set,
  476. @var{filename} is used as a string format with the segment number:
  477. @example
  478. ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
  479. @end example
  480. This example will produce the playlist, @file{out.m3u8}, and segment files:
  481. @file{file000.ts}, @file{file001.ts}, @file{file002.ts}, etc.
  482. @var{filename} may contain full path or relative path specification,
  483. but only the file name part without any path info will be contained in the m3u8 segment list.
  484. Should a relative path be specified, the path of the created segment
  485. files will be relative to the current working directory.
  486. When strftime_mkdir is set, the whole expanded value of @var{filename} will be written into the m3u8 segment list.
  487. When @code{var_stream_map} is set with two or more variant streams, the
  488. @var{filename} pattern must contain the string "%v", this string specifies
  489. the position of variant stream index in the generated segment file names.
  490. @example
  491. ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
  492. -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" \
  493. -hls_segment_filename 'file_%v_%03d.ts' out_%v.m3u8
  494. @end example
  495. This example will produce the playlists segment file sets:
  496. @file{file_0_000.ts}, @file{file_0_001.ts}, @file{file_0_002.ts}, etc. and
  497. @file{file_1_000.ts}, @file{file_1_001.ts}, @file{file_1_002.ts}, etc.
  498. The string "%v" may be present in the filename or in the last directory name
  499. containing the file. If the string is present in the directory name, then
  500. sub-directories are created after expanding the directory name pattern. This
  501. enables creation of segments corresponding to different variant streams in
  502. subdirectories.
  503. @example
  504. ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
  505. -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" \
  506. -hls_segment_filename 'vs%v/file_%03d.ts' vs%v/out.m3u8
  507. @end example
  508. This example will produce the playlists segment file sets:
  509. @file{vs0/file_000.ts}, @file{vs0/file_001.ts}, @file{vs0/file_002.ts}, etc. and
  510. @file{vs1/file_000.ts}, @file{vs1/file_001.ts}, @file{vs1/file_002.ts}, etc.
  511. @item use_localtime
  512. Same as strftime option, will be deprecated.
  513. @item strftime
  514. Use strftime() on @var{filename} to expand the segment filename with localtime.
  515. The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
  516. hls_flag and %%d will be the specifier.
  517. @example
  518. ffmpeg -i in.nut -strftime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
  519. @end example
  520. This example will produce the playlist, @file{out.m3u8}, and segment files:
  521. @file{file-20160215-1455569023.ts}, @file{file-20160215-1455569024.ts}, etc.
  522. Note: On some systems/environments, the @code{%s} specifier is not available. See
  523. @code{strftime()} documentation.
  524. @example
  525. ffmpeg -i in.nut -strftime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
  526. @end example
  527. This example will produce the playlist, @file{out.m3u8}, and segment files:
  528. @file{file-20160215-0001.ts}, @file{file-20160215-0002.ts}, etc.
  529. @item use_localtime_mkdir
  530. Same as strftime_mkdir option, will be deprecated .
  531. @item strftime_mkdir
  532. Used together with -strftime_mkdir, it will create all subdirectories which
  533. is expanded in @var{filename}.
  534. @example
  535. ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y%m%d/file-%Y%m%d-%s.ts' out.m3u8
  536. @end example
  537. This example will create a directory 201560215 (if it does not exist), and then
  538. produce the playlist, @file{out.m3u8}, and segment files:
  539. @file{20160215/file-20160215-1455569023.ts}, @file{20160215/file-20160215-1455569024.ts}, etc.
  540. @example
  541. ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y/%m/%d/file-%Y%m%d-%s.ts' out.m3u8
  542. @end example
  543. This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
  544. produce the playlist, @file{out.m3u8}, and segment files:
  545. @file{2016/02/15/file-20160215-1455569023.ts}, @file{2016/02/15/file-20160215-1455569024.ts}, etc.
  546. @item hls_key_info_file @var{key_info_file}
  547. Use the information in @var{key_info_file} for segment encryption. The first
  548. line of @var{key_info_file} specifies the key URI written to the playlist. The
  549. key URL is used to access the encryption key during playback. The second line
  550. specifies the path to the key file used to obtain the key during the encryption
  551. process. The key file is read as a single packed array of 16 octets in binary
  552. format. The optional third line specifies the initialization vector (IV) as a
  553. hexadecimal string to be used instead of the segment sequence number (default)
  554. for encryption. Changes to @var{key_info_file} will result in segment
  555. encryption with the new key/IV and an entry in the playlist for the new key
  556. URI/IV if @code{hls_flags periodic_rekey} is enabled.
  557. Key info file format:
  558. @example
  559. @var{key URI}
  560. @var{key file path}
  561. @var{IV} (optional)
  562. @end example
  563. Example key URIs:
  564. @example
  565. http://server/file.key
  566. /path/to/file.key
  567. file.key
  568. @end example
  569. Example key file paths:
  570. @example
  571. file.key
  572. /path/to/file.key
  573. @end example
  574. Example IV:
  575. @example
  576. 0123456789ABCDEF0123456789ABCDEF
  577. @end example
  578. Key info file example:
  579. @example
  580. http://server/file.key
  581. /path/to/file.key
  582. 0123456789ABCDEF0123456789ABCDEF
  583. @end example
  584. Example shell script:
  585. @example
  586. #!/bin/sh
  587. BASE_URL=$@{1:-'.'@}
  588. openssl rand 16 > file.key
  589. echo $BASE_URL/file.key > file.keyinfo
  590. echo file.key >> file.keyinfo
  591. echo $(openssl rand -hex 16) >> file.keyinfo
  592. ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
  593. -hls_key_info_file file.keyinfo out.m3u8
  594. @end example
  595. @item -hls_enc @var{enc}
  596. Enable (1) or disable (0) the AES128 encryption.
  597. When enabled every segment generated is encrypted and the encryption key
  598. is saved as @var{playlist name}.key.
  599. @item -hls_enc_key @var{key}
  600. Hex-coded 16byte key to encrypt the segments, by default it
  601. is randomly generated.
  602. @item -hls_enc_key_url @var{keyurl}
  603. If set, @var{keyurl} is prepended instead of @var{baseurl} to the key filename
  604. in the playlist.
  605. @item -hls_enc_iv @var{iv}
  606. Hex-coded 16byte initialization vector for every segment instead
  607. of the autogenerated ones.
  608. @item hls_segment_type @var{flags}
  609. Possible values:
  610. @table @samp
  611. @item mpegts
  612. Output segment files in MPEG-2 Transport Stream format. This is
  613. compatible with all HLS versions.
  614. @item fmp4
  615. Output segment files in fragmented MP4 format, similar to MPEG-DASH.
  616. fmp4 files may be used in HLS version 7 and above.
  617. @end table
  618. @item hls_fmp4_init_filename @var{filename}
  619. Set filename to the fragment files header file, default filename is @file{init.mp4}.
  620. When @code{var_stream_map} is set with two or more variant streams, the
  621. @var{filename} pattern must contain the string "%v", this string specifies
  622. the position of variant stream index in the generated init file names.
  623. The string "%v" may be present in the filename or in the last directory name
  624. containing the file. If the string is present in the directory name, then
  625. sub-directories are created after expanding the directory name pattern. This
  626. enables creation of init files corresponding to different variant streams in
  627. subdirectories.
  628. @item hls_flags @var{flags}
  629. Possible values:
  630. @table @samp
  631. @item single_file
  632. If this flag is set, the muxer will store all segments in a single MPEG-TS
  633. file, and will use byte ranges in the playlist. HLS playlists generated with
  634. this way will have the version number 4.
  635. For example:
  636. @example
  637. ffmpeg -i in.nut -hls_flags single_file out.m3u8
  638. @end example
  639. Will produce the playlist, @file{out.m3u8}, and a single segment file,
  640. @file{out.ts}.
  641. @item delete_segments
  642. Segment files removed from the playlist are deleted after a period of time
  643. equal to the duration of the segment plus the duration of the playlist.
  644. @item append_list
  645. Append new segments into the end of old segment list,
  646. and remove the @code{#EXT-X-ENDLIST} from the old segment list.
  647. @item round_durations
  648. Round the duration info in the playlist file segment info to integer
  649. values, instead of using floating point.
  650. @item discont_start
  651. Add the @code{#EXT-X-DISCONTINUITY} tag to the playlist, before the
  652. first segment's information.
  653. @item omit_endlist
  654. Do not append the @code{EXT-X-ENDLIST} tag at the end of the playlist.
  655. @item periodic_rekey
  656. The file specified by @code{hls_key_info_file} will be checked periodically and
  657. detect updates to the encryption info. Be sure to replace this file atomically,
  658. including the file containing the AES encryption key.
  659. @item independent_segments
  660. Add the @code{#EXT-X-INDEPENDENT-SEGMENTS} to playlists that has video segments
  661. and when all the segments of that playlist are guaranteed to start with a Key frame.
  662. @item split_by_time
  663. Allow segments to start on frames other than keyframes. This improves
  664. behavior on some players when the time between keyframes is inconsistent,
  665. but may make things worse on others, and can cause some oddities during
  666. seeking. This flag should be used with the @code{hls_time} option.
  667. @item program_date_time
  668. Generate @code{EXT-X-PROGRAM-DATE-TIME} tags.
  669. @item second_level_segment_index
  670. Makes it possible to use segment indexes as %%d in hls_segment_filename expression
  671. besides date/time values when strftime is on.
  672. To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
  673. @item second_level_segment_size
  674. Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
  675. expression besides date/time values when strftime is on.
  676. To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
  677. @item second_level_segment_duration
  678. Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
  679. expression besides date/time values when strftime is on.
  680. To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
  681. @example
  682. ffmpeg -i sample.mpeg \
  683. -f hls -hls_time 3 -hls_list_size 5 \
  684. -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
  685. -strftime 1 -strftime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
  686. @end example
  687. This will produce segments like this:
  688. @file{segment_20170102194334_0003_00122200_0000003000000.ts}, @file{segment_20170102194334_0004_00120072_0000003000000.ts} etc.
  689. @item temp_file
  690. Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
  691. serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
  692. before they have been added to the m3u8 playlist.
  693. @end table
  694. @item hls_playlist_type event
  695. Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
  696. @option{hls_list_size} to 0; the playlist can only be appended to.
  697. @item hls_playlist_type vod
  698. Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
  699. @option{hls_list_size} to 0; the playlist must not change.
  700. @item method
  701. Use the given HTTP method to create the hls files.
  702. @example
  703. ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
  704. @end example
  705. This example will upload all the mpegts segment files to the HTTP
  706. server using the HTTP PUT method, and update the m3u8 files every
  707. @code{refresh} times using the same method.
  708. Note that the HTTP server must support the given method for uploading
  709. files.
  710. @item http_user_agent
  711. Override User-Agent field in HTTP header. Applicable only for HTTP output.
  712. @item var_stream_map
  713. Map string which specifies how to group the audio, video and subtitle streams
  714. into different variant streams. The variant stream groups are separated
  715. by space.
  716. Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
  717. the keys to specify audio, video and subtitle streams respectively.
  718. Allowed values are 0 to 9 (limited just based on practical usage).
  719. When there are two or more variant streams, the output filename pattern must
  720. contain the string "%v", this string specifies the position of variant stream
  721. index in the output media playlist filenames. The string "%v" may be present in
  722. the filename or in the last directory name containing the file. If the string is
  723. present in the directory name, then sub-directories are created after expanding
  724. the directory name pattern. This enables creation of variant streams in
  725. subdirectories.
  726. @example
  727. ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
  728. -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" \
  729. http://example.com/live/out_%v.m3u8
  730. @end example
  731. This example creates two hls variant streams. The first variant stream will
  732. contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
  733. second variant stream will contain video stream of bitrate 256k and audio
  734. stream of bitrate 32k. Here, two media playlist with file names out_0.m3u8 and
  735. out_1.m3u8 will be created.
  736. @example
  737. ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
  738. -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
  739. http://example.com/live/out_%v.m3u8
  740. @end example
  741. This example creates three hls variant streams. The first variant stream will
  742. be a video only stream with video bitrate 1000k, the second variant stream will
  743. be an audio only stream with bitrate 64k and the third variant stream will be a
  744. video only stream with bitrate 256k. Here, three media playlist with file names
  745. out_0.m3u8, out_1.m3u8 and out_2.m3u8 will be created.
  746. @example
  747. ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
  748. -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" \
  749. http://example.com/live/vs_%v/out.m3u8
  750. @end example
  751. This example creates the variant streams in subdirectories. Here, the first
  752. media playlist is created at @file{http://example.com/live/vs_0/out.m3u8} and
  753. the second one at @file{http://example.com/live/vs_1/out.m3u8}.
  754. @example
  755. ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k \
  756. -map 0:a -map 0:a -map 0:v -map 0:v -f hls \
  757. -var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
  758. -master_pl_name master.m3u8 \
  759. http://example.com/live/out_%v.m3u8
  760. @end example
  761. This example creates two audio only and two video only variant streams. In
  762. addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
  763. playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
  764. and they are mapped to the two video only variant streams with audio group names
  765. 'aud_low' and 'aud_high'.
  766. By default, a single hls variant containing all the encoded streams is created.
  767. @example
  768. ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
  769. -map 0:a -map 0:a -map 0:v -f hls \
  770. -var_stream_map "a:0,agroup:aud_low,default:yes a:1,agroup:aud_low v:0,agroup:aud_low" \
  771. -master_pl_name master.m3u8 \
  772. http://example.com/live/out_%v.m3u8
  773. @end example
  774. This example creates two audio only and one video only variant streams. In
  775. addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
  776. playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
  777. and they are mapped to the one video only variant streams with audio group name
  778. 'aud_low', and the audio group have default stat is NO or YES.
  779. By default, a single hls variant containing all the encoded streams is created.
  780. @example
  781. ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
  782. -map 0:a -map 0:a -map 0:v -f hls \
  783. -var_stream_map "a:0,agroup:aud_low,default:yes,language=ENG a:1,agroup:aud_low,language:CHN v:0,agroup:aud_low" \
  784. -master_pl_name master.m3u8 \
  785. http://example.com/live/out_%v.m3u8
  786. @end example
  787. This example creates two audio only and one video only variant streams. In
  788. addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
  789. playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
  790. and they are mapped to the one video only variant streams with audio group name
  791. 'aud_low', and the audio group have default stat is NO or YES, and one audio
  792. have and language is named ENG, the other audio language is named CHN.
  793. By default, a single hls variant containing all the encoded streams is created.
  794. @item cc_stream_map
  795. Map string which specifies different closed captions groups and their
  796. attributes. The closed captions stream groups are separated by space.
  797. Expected string format is like this
  798. "ccgroup:<group name>,instreamid:<INSTREAM-ID>,language:<language code> ....".
  799. 'ccgroup' and 'instreamid' are mandatory attributes. 'language' is an optional
  800. attribute.
  801. The closed captions groups configured using this option are mapped to different
  802. variant streams by providing the same 'ccgroup' name in the
  803. @code{var_stream_map} string. If @code{var_stream_map} is not set, then the
  804. first available ccgroup in @code{cc_stream_map} is mapped to the output variant
  805. stream. The examples for these two use cases are given below.
  806. @example
  807. ffmpeg -re -i in.ts -b:v 1000k -b:a 64k -a53cc 1 -f hls \
  808. -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en" \
  809. -master_pl_name master.m3u8 \
  810. http://example.com/live/out.m3u8
  811. @end example
  812. This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=CLOSED-CAPTIONS} in
  813. the master playlist with group name 'cc', language 'en' (english) and
  814. INSTREAM-ID 'CC1'. Also, it adds @code{CLOSED-CAPTIONS} attribute with group
  815. name 'cc' for the output variant stream.
  816. @example
  817. ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
  818. -a53cc:0 1 -a53cc:1 1\
  819. -map 0:v -map 0:a -map 0:v -map 0:a -f hls \
  820. -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en ccgroup:cc,instreamid:CC2,language:sp" \
  821. -var_stream_map "v:0,a:0,ccgroup:cc v:1,a:1,ccgroup:cc" \
  822. -master_pl_name master.m3u8 \
  823. http://example.com/live/out_%v.m3u8
  824. @end example
  825. This example adds two @code{#EXT-X-MEDIA} tags with @code{TYPE=CLOSED-CAPTIONS} in
  826. the master playlist for the INSTREAM-IDs 'CC1' and 'CC2'. Also, it adds
  827. @code{CLOSED-CAPTIONS} attribute with group name 'cc' for the two output variant
  828. streams.
  829. @item master_pl_name
  830. Create HLS master playlist with the given name.
  831. @example
  832. ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
  833. @end example
  834. This example creates HLS master playlist with name master.m3u8 and it is
  835. published at http://example.com/live/
  836. @item master_pl_publish_rate
  837. Publish master play list repeatedly every after specified number of segment intervals.
  838. @example
  839. ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
  840. -hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
  841. @end example
  842. This example creates HLS master playlist with name master.m3u8 and keep
  843. publishing it repeatedly every after 30 segments i.e. every after 60s.
  844. @item http_persistent
  845. Use persistent HTTP connections. Applicable only for HTTP output.
  846. @item timeout
  847. Set timeout for socket I/O operations. Applicable only for HTTP output.
  848. @item -ignore_io_errors
  849. Ignore IO errors during open, write and delete. Useful for long-duration runs with network output.
  850. @end table
  851. @anchor{ico}
  852. @section ico
  853. ICO file muxer.
  854. Microsoft's icon file format (ICO) has some strict limitations that should be noted:
  855. @itemize
  856. @item
  857. Size cannot exceed 256 pixels in any dimension
  858. @item
  859. Only BMP and PNG images can be stored
  860. @item
  861. If a BMP image is used, it must be one of the following pixel formats:
  862. @example
  863. BMP Bit Depth FFmpeg Pixel Format
  864. 1bit pal8
  865. 4bit pal8
  866. 8bit pal8
  867. 16bit rgb555le
  868. 24bit bgr24
  869. 32bit bgra
  870. @end example
  871. @item
  872. If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
  873. @item
  874. If a PNG image is used, it must use the rgba pixel format
  875. @end itemize
  876. @anchor{image2}
  877. @section image2
  878. Image file muxer.
  879. The image file muxer writes video frames to image files.
  880. The output filenames are specified by a pattern, which can be used to
  881. produce sequentially numbered series of files.
  882. The pattern may contain the string "%d" or "%0@var{N}d", this string
  883. specifies the position of the characters representing a numbering in
  884. the filenames. If the form "%0@var{N}d" is used, the string
  885. representing the number in each filename is 0-padded to @var{N}
  886. digits. The literal character '%' can be specified in the pattern with
  887. the string "%%".
  888. If the pattern contains "%d" or "%0@var{N}d", the first filename of
  889. the file list specified will contain the number 1, all the following
  890. numbers will be sequential.
  891. The pattern may contain a suffix which is used to automatically
  892. determine the format of the image files to write.
  893. For example the pattern "img-%03d.bmp" will specify a sequence of
  894. filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
  895. @file{img-010.bmp}, etc.
  896. The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
  897. form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
  898. etc.
  899. @subsection Examples
  900. The following example shows how to use @command{ffmpeg} for creating a
  901. sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
  902. taking one image every second from the input video:
  903. @example
  904. ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
  905. @end example
  906. Note that with @command{ffmpeg}, if the format is not specified with the
  907. @code{-f} option and the output filename specifies an image file
  908. format, the image2 muxer is automatically selected, so the previous
  909. command can be written as:
  910. @example
  911. ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
  912. @end example
  913. Note also that the pattern must not necessarily contain "%d" or
  914. "%0@var{N}d", for example to create a single image file
  915. @file{img.jpeg} from the start of the input video you can employ the command:
  916. @example
  917. ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
  918. @end example
  919. The @option{strftime} option allows you to expand the filename with
  920. date and time information. Check the documentation of
  921. the @code{strftime()} function for the syntax.
  922. For example to generate image files from the @code{strftime()}
  923. "%Y-%m-%d_%H-%M-%S" pattern, the following @command{ffmpeg} command
  924. can be used:
  925. @example
  926. ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
  927. @end example
  928. You can set the file name with current frame's PTS:
  929. @example
  930. ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
  931. @end example
  932. @subsection Options
  933. @table @option
  934. @item frame_pts
  935. If set to 1, expand the filename with pts from pkt->pts.
  936. Default value is 0.
  937. @item start_number
  938. Start the sequence from the specified number. Default value is 1.
  939. @item update
  940. If set to 1, the filename will always be interpreted as just a
  941. filename, not a pattern, and the corresponding file will be continuously
  942. overwritten with new images. Default value is 0.
  943. @item strftime
  944. If set to 1, expand the filename with date and time information from
  945. @code{strftime()}. Default value is 0.
  946. @end table
  947. The image muxer supports the .Y.U.V image file format. This format is
  948. special in that that each image frame consists of three files, for
  949. each of the YUV420P components. To read or write this image file format,
  950. specify the name of the '.Y' file. The muxer will automatically open the
  951. '.U' and '.V' files as required.
  952. @section matroska
  953. Matroska container muxer.
  954. This muxer implements the matroska and webm container specs.
  955. @subsection Metadata
  956. The recognized metadata settings in this muxer are:
  957. @table @option
  958. @item title
  959. Set title name provided to a single track.
  960. @item language
  961. Specify the language of the track in the Matroska languages form.
  962. The language can be either the 3 letters bibliographic ISO-639-2 (ISO
  963. 639-2/B) form (like "fre" for French), or a language code mixed with a
  964. country code for specialities in languages (like "fre-ca" for Canadian
  965. French).
  966. @item stereo_mode
  967. Set stereo 3D video layout of two views in a single video track.
  968. The following values are recognized:
  969. @table @samp
  970. @item mono
  971. video is not stereo
  972. @item left_right
  973. Both views are arranged side by side, Left-eye view is on the left
  974. @item bottom_top
  975. Both views are arranged in top-bottom orientation, Left-eye view is at bottom
  976. @item top_bottom
  977. Both views are arranged in top-bottom orientation, Left-eye view is on top
  978. @item checkerboard_rl
  979. Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
  980. @item checkerboard_lr
  981. Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
  982. @item row_interleaved_rl
  983. Each view is constituted by a row based interleaving, Right-eye view is first row
  984. @item row_interleaved_lr
  985. Each view is constituted by a row based interleaving, Left-eye view is first row
  986. @item col_interleaved_rl
  987. Both views are arranged in a column based interleaving manner, Right-eye view is first column
  988. @item col_interleaved_lr
  989. Both views are arranged in a column based interleaving manner, Left-eye view is first column
  990. @item anaglyph_cyan_red
  991. All frames are in anaglyph format viewable through red-cyan filters
  992. @item right_left
  993. Both views are arranged side by side, Right-eye view is on the left
  994. @item anaglyph_green_magenta
  995. All frames are in anaglyph format viewable through green-magenta filters
  996. @item block_lr
  997. Both eyes laced in one Block, Left-eye view is first
  998. @item block_rl
  999. Both eyes laced in one Block, Right-eye view is first
  1000. @end table
  1001. @end table
  1002. For example a 3D WebM clip can be created using the following command line:
  1003. @example
  1004. ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
  1005. @end example
  1006. @subsection Options
  1007. This muxer supports the following options:
  1008. @table @option
  1009. @item reserve_index_space
  1010. By default, this muxer writes the index for seeking (called cues in Matroska
  1011. terms) at the end of the file, because it cannot know in advance how much space
  1012. to leave for the index at the beginning of the file. However for some use cases
  1013. -- e.g. streaming where seeking is possible but slow -- it is useful to put the
  1014. index at the beginning of the file.
  1015. If this option is set to a non-zero value, the muxer will reserve a given amount
  1016. of space in the file header and then try to write the cues there when the muxing
  1017. finishes. If the available space does not suffice, muxing will fail. A safe size
  1018. for most use cases should be about 50kB per hour of video.
  1019. Note that cues are only written if the output is seekable and this option will
  1020. have no effect if it is not.
  1021. @end table
  1022. @anchor{md5}
  1023. @section md5
  1024. MD5 testing format.
  1025. This is a variant of the @ref{hash} muxer. Unlike that muxer, it
  1026. defaults to using the MD5 hash function.
  1027. @subsection Examples
  1028. To compute the MD5 hash of the input converted to raw
  1029. audio and video, and store it in the file @file{out.md5}:
  1030. @example
  1031. ffmpeg -i INPUT -f md5 out.md5
  1032. @end example
  1033. You can print the MD5 to stdout with the command:
  1034. @example
  1035. ffmpeg -i INPUT -f md5 -
  1036. @end example
  1037. See also the @ref{hash} and @ref{framemd5} muxers.
  1038. @section mov, mp4, ismv
  1039. MOV/MP4/ISMV (Smooth Streaming) muxer.
  1040. The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
  1041. file has all the metadata about all packets stored in one location
  1042. (written at the end of the file, it can be moved to the start for
  1043. better playback by adding @var{faststart} to the @var{movflags}, or
  1044. using the @command{qt-faststart} tool). A fragmented
  1045. file consists of a number of fragments, where packets and metadata
  1046. about these packets are stored together. Writing a fragmented
  1047. file has the advantage that the file is decodable even if the
  1048. writing is interrupted (while a normal MOV/MP4 is undecodable if
  1049. it is not properly finished), and it requires less memory when writing
  1050. very long files (since writing normal MOV/MP4 files stores info about
  1051. every single packet in memory until the file is closed). The downside
  1052. is that it is less compatible with other applications.
  1053. @subsection Options
  1054. Fragmentation is enabled by setting one of the AVOptions that define
  1055. how to cut the file into fragments:
  1056. @table @option
  1057. @item -moov_size @var{bytes}
  1058. Reserves space for the moov atom at the beginning of the file instead of placing the
  1059. moov atom at the end. If the space reserved is insufficient, muxing will fail.
  1060. @item -movflags frag_keyframe
  1061. Start a new fragment at each video keyframe.
  1062. @item -frag_duration @var{duration}
  1063. Create fragments that are @var{duration} microseconds long.
  1064. @item -frag_size @var{size}
  1065. Create fragments that contain up to @var{size} bytes of payload data.
  1066. @item -movflags frag_custom
  1067. Allow the caller to manually choose when to cut fragments, by
  1068. calling @code{av_write_frame(ctx, NULL)} to write a fragment with
  1069. the packets written so far. (This is only useful with other
  1070. applications integrating libavformat, not from @command{ffmpeg}.)
  1071. @item -min_frag_duration @var{duration}
  1072. Don't create fragments that are shorter than @var{duration} microseconds long.
  1073. @end table
  1074. If more than one condition is specified, fragments are cut when
  1075. one of the specified conditions is fulfilled. The exception to this is
  1076. @code{-min_frag_duration}, which has to be fulfilled for any of the other
  1077. conditions to apply.
  1078. Additionally, the way the output file is written can be adjusted
  1079. through a few other options:
  1080. @table @option
  1081. @item -movflags empty_moov
  1082. Write an initial moov atom directly at the start of the file, without
  1083. describing any samples in it. Generally, an mdat/moov pair is written
  1084. at the start of the file, as a normal MOV/MP4 file, containing only
  1085. a short portion of the file. With this option set, there is no initial
  1086. mdat atom, and the moov atom only describes the tracks but has
  1087. a zero duration.
  1088. This option is implicitly set when writing ismv (Smooth Streaming) files.
  1089. @item -movflags separate_moof
  1090. Write a separate moof (movie fragment) atom for each track. Normally,
  1091. packets for all tracks are written in a moof atom (which is slightly
  1092. more efficient), but with this option set, the muxer writes one moof/mdat
  1093. pair for each track, making it easier to separate tracks.
  1094. This option is implicitly set when writing ismv (Smooth Streaming) files.
  1095. @item -movflags skip_sidx
  1096. Skip writing of sidx atom. When bitrate overhead due to sidx atom is high,
  1097. this option could be used for cases where sidx atom is not mandatory.
  1098. When global_sidx flag is enabled, this option will be ignored.
  1099. @item -movflags faststart
  1100. Run a second pass moving the index (moov atom) to the beginning of the file.
  1101. This operation can take a while, and will not work in various situations such
  1102. as fragmented output, thus it is not enabled by default.
  1103. @item -movflags rtphint
  1104. Add RTP hinting tracks to the output file.
  1105. @item -movflags disable_chpl
  1106. Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
  1107. and a QuickTime chapter track are written to the file. With this option
  1108. set, only the QuickTime chapter track will be written. Nero chapters can
  1109. cause failures when the file is reprocessed with certain tagging programs, like
  1110. mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
  1111. @item -movflags omit_tfhd_offset
  1112. Do not write any absolute base_data_offset in tfhd atoms. This avoids
  1113. tying fragments to absolute byte positions in the file/streams.
  1114. @item -movflags default_base_moof
  1115. Similarly to the omit_tfhd_offset, this flag avoids writing the
  1116. absolute base_data_offset field in tfhd atoms, but does so by using
  1117. the new default-base-is-moof flag instead. This flag is new from
  1118. 14496-12:2012. This may make the fragments easier to parse in certain
  1119. circumstances (avoiding basing track fragment location calculations
  1120. on the implicit end of the previous track fragment).
  1121. @item -write_tmcd
  1122. Specify @code{on} to force writing a timecode track, @code{off} to disable it
  1123. and @code{auto} to write a timecode track only for mov and mp4 output (default).
  1124. @item -movflags negative_cts_offsets
  1125. Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
  1126. be negative. This enables the initial sample to have DTS/CTS of zero, and
  1127. reduces the need for edit lists for some cases such as video tracks with
  1128. B-frames. Additionally, eases conformance with the DASH-IF interoperability
  1129. guidelines.
  1130. This option is implicitly set when writing ismv (Smooth Streaming) files.
  1131. @item -write_prft
  1132. Write producer time reference box (PRFT) with a specified time source for the
  1133. NTP field in the PRFT box. Set value as @samp{wallclock} to specify timesource
  1134. as wallclock time and @samp{pts} to specify timesource as input packets' PTS
  1135. values.
  1136. Setting value to @samp{pts} is applicable only for a live encoding use case,
  1137. where PTS values are set as as wallclock time at the source. For example, an
  1138. encoding use case with decklink capture source where @option{video_pts} and
  1139. @option{audio_pts} are set to @samp{abs_wallclock}.
  1140. @end table
  1141. @subsection Example
  1142. Smooth Streaming content can be pushed in real time to a publishing
  1143. point on IIS with this muxer. Example:
  1144. @example
  1145. ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
  1146. @end example
  1147. @subsection Audible AAX
  1148. Audible AAX files are encrypted M4B files, and they can be decrypted by specifying a 4 byte activation secret.
  1149. @example
  1150. ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
  1151. @end example
  1152. @section mp3
  1153. The MP3 muxer writes a raw MP3 stream with the following optional features:
  1154. @itemize @bullet
  1155. @item
  1156. An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
  1157. 2.4 are supported, the @code{id3v2_version} private option controls which one is
  1158. used (3 or 4). Setting @code{id3v2_version} to 0 disables the ID3v2 header
  1159. completely.
  1160. The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
  1161. The pictures are supplied to the muxer in form of a video stream with a single
  1162. packet. There can be any number of those streams, each will correspond to a
  1163. single APIC frame. The stream metadata tags @var{title} and @var{comment} map
  1164. to APIC @var{description} and @var{picture type} respectively. See
  1165. @url{http://id3.org/id3v2.4.0-frames} for allowed picture types.
  1166. Note that the APIC frames must be written at the beginning, so the muxer will
  1167. buffer the audio frames until it gets all the pictures. It is therefore advised
  1168. to provide the pictures as soon as possible to avoid excessive buffering.
  1169. @item
  1170. A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
  1171. default, but will be written only if the output is seekable. The
  1172. @code{write_xing} private option can be used to disable it. The frame contains
  1173. various information that may be useful to the decoder, like the audio duration
  1174. or encoder delay.
  1175. @item
  1176. A legacy ID3v1 tag at the end of the file (disabled by default). It may be
  1177. enabled with the @code{write_id3v1} private option, but as its capabilities are
  1178. very limited, its usage is not recommended.
  1179. @end itemize
  1180. Examples:
  1181. Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
  1182. @example
  1183. ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
  1184. @end example
  1185. To attach a picture to an mp3 file select both the audio and the picture stream
  1186. with @code{map}:
  1187. @example
  1188. ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
  1189. -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
  1190. @end example
  1191. Write a "clean" MP3 without any extra features:
  1192. @example
  1193. ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
  1194. @end example
  1195. @section mpegts
  1196. MPEG transport stream muxer.
  1197. This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
  1198. The recognized metadata settings in mpegts muxer are @code{service_provider}
  1199. and @code{service_name}. If they are not set the default for
  1200. @code{service_provider} is @samp{FFmpeg} and the default for
  1201. @code{service_name} is @samp{Service01}.
  1202. @subsection Options
  1203. The muxer options are:
  1204. @table @option
  1205. @item mpegts_transport_stream_id @var{integer}
  1206. Set the @samp{transport_stream_id}. This identifies a transponder in DVB.
  1207. Default is @code{0x0001}.
  1208. @item mpegts_original_network_id @var{integer}
  1209. Set the @samp{original_network_id}. This is unique identifier of a
  1210. network in DVB. Its main use is in the unique identification of a service
  1211. through the path @samp{Original_Network_ID, Transport_Stream_ID}. Default
  1212. is @code{0x0001}.
  1213. @item mpegts_service_id @var{integer}
  1214. Set the @samp{service_id}, also known as program in DVB. Default is
  1215. @code{0x0001}.
  1216. @item mpegts_service_type @var{integer}
  1217. Set the program @samp{service_type}. Default is @code{digital_tv}.
  1218. Accepts the following options:
  1219. @table @samp
  1220. @item hex_value
  1221. Any hexadecimal value between @code{0x01} and @code{0xff} as defined in
  1222. ETSI 300 468.
  1223. @item digital_tv
  1224. Digital TV service.
  1225. @item digital_radio
  1226. Digital Radio service.
  1227. @item teletext
  1228. Teletext service.
  1229. @item advanced_codec_digital_radio
  1230. Advanced Codec Digital Radio service.
  1231. @item mpeg2_digital_hdtv
  1232. MPEG2 Digital HDTV service.
  1233. @item advanced_codec_digital_sdtv
  1234. Advanced Codec Digital SDTV service.
  1235. @item advanced_codec_digital_hdtv
  1236. Advanced Codec Digital HDTV service.
  1237. @end table
  1238. @item mpegts_pmt_start_pid @var{integer}
  1239. Set the first PID for PMT. Default is @code{0x1000}. Max is @code{0x1f00}.
  1240. @item mpegts_start_pid @var{integer}
  1241. Set the first PID for data packets. Default is @code{0x0100}. Max is
  1242. @code{0x0f00}.
  1243. @item mpegts_m2ts_mode @var{boolean}
  1244. Enable m2ts mode if set to @code{1}. Default value is @code{-1} which
  1245. disables m2ts mode.
  1246. @item muxrate @var{integer}
  1247. Set a constant muxrate. Default is VBR.
  1248. @item pes_payload_size @var{integer}
  1249. Set minimum PES packet payload in bytes. Default is @code{2930}.
  1250. @item mpegts_flags @var{flags}
  1251. Set mpegts flags. Accepts the following options:
  1252. @table @samp
  1253. @item resend_headers
  1254. Reemit PAT/PMT before writing the next packet.
  1255. @item latm
  1256. Use LATM packetization for AAC.
  1257. @item pat_pmt_at_frames
  1258. Reemit PAT and PMT at each video frame.
  1259. @item system_b
  1260. Conform to System B (DVB) instead of System A (ATSC).
  1261. @item initial_discontinuity
  1262. Mark the initial packet of each stream as discontinuity.
  1263. @end table
  1264. @item resend_headers @var{integer}
  1265. Reemit PAT/PMT before writing the next packet. This option is deprecated:
  1266. use @option{mpegts_flags} instead.
  1267. @item mpegts_copyts @var{boolean}
  1268. Preserve original timestamps, if value is set to @code{1}. Default value
  1269. is @code{-1}, which results in shifting timestamps so that they start from 0.
  1270. @item omit_video_pes_length @var{boolean}
  1271. Omit the PES packet length for video packets. Default is @code{1} (true).
  1272. @item pcr_period @var{integer}
  1273. Override the default PCR retransmission time in milliseconds. Ignored if
  1274. variable muxrate is selected. Default is @code{20}.
  1275. @item pat_period @var{double}
  1276. Maximum time in seconds between PAT/PMT tables.
  1277. @item sdt_period @var{double}
  1278. Maximum time in seconds between SDT tables.
  1279. @item tables_version @var{integer}
  1280. Set PAT, PMT and SDT version (default @code{0}, valid values are from 0 to 31, inclusively).
  1281. This option allows updating stream structure so that standard consumer may
  1282. detect the change. To do so, reopen output @code{AVFormatContext} (in case of API
  1283. usage) or restart @command{ffmpeg} instance, cyclically changing
  1284. @option{tables_version} value:
  1285. @example
  1286. ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
  1287. ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
  1288. ...
  1289. ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
  1290. ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
  1291. ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
  1292. ...
  1293. @end example
  1294. @end table
  1295. @subsection Example
  1296. @example
  1297. ffmpeg -i file.mpg -c copy \
  1298. -mpegts_original_network_id 0x1122 \
  1299. -mpegts_transport_stream_id 0x3344 \
  1300. -mpegts_service_id 0x5566 \
  1301. -mpegts_pmt_start_pid 0x1500 \
  1302. -mpegts_start_pid 0x150 \
  1303. -metadata service_provider="Some provider" \
  1304. -metadata service_name="Some Channel" \
  1305. out.ts
  1306. @end example
  1307. @section mxf, mxf_d10, mxf_opatom
  1308. MXF muxer.
  1309. @subsection Options
  1310. The muxer options are:
  1311. @table @option
  1312. @item store_user_comments @var{bool}
  1313. Set if user comments should be stored if available or never.
  1314. IRT D-10 does not allow user comments. The default is thus to write them for
  1315. mxf and mxf_opatom but not for mxf_d10
  1316. @end table
  1317. @section null
  1318. Null muxer.
  1319. This muxer does not generate any output file, it is mainly useful for
  1320. testing or benchmarking purposes.
  1321. For example to benchmark decoding with @command{ffmpeg} you can use the
  1322. command:
  1323. @example
  1324. ffmpeg -benchmark -i INPUT -f null out.null
  1325. @end example
  1326. Note that the above command does not read or write the @file{out.null}
  1327. file, but specifying the output file is required by the @command{ffmpeg}
  1328. syntax.
  1329. Alternatively you can write the command as:
  1330. @example
  1331. ffmpeg -benchmark -i INPUT -f null -
  1332. @end example
  1333. @section nut
  1334. @table @option
  1335. @item -syncpoints @var{flags}
  1336. Change the syncpoint usage in nut:
  1337. @table @option
  1338. @item @var{default} use the normal low-overhead seeking aids.
  1339. @item @var{none} do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;
  1340. Use of this option is not recommended, as the resulting files are very damage
  1341. sensitive and seeking is not possible. Also in general the overhead from
  1342. syncpoints is negligible. Note, -@code{write_index} 0 can be used to disable
  1343. all growing data tables, allowing to mux endless streams with limited memory
  1344. and without these disadvantages.
  1345. @item @var{timestamped} extend the syncpoint with a wallclock field.
  1346. @end table
  1347. The @var{none} and @var{timestamped} flags are experimental.
  1348. @item -write_index @var{bool}
  1349. Write index at the end, the default is to write an index.
  1350. @end table
  1351. @example
  1352. ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
  1353. @end example
  1354. @section ogg
  1355. Ogg container muxer.
  1356. @table @option
  1357. @item -page_duration @var{duration}
  1358. Preferred page duration, in microseconds. The muxer will attempt to create
  1359. pages that are approximately @var{duration} microseconds long. This allows the
  1360. user to compromise between seek granularity and container overhead. The default
  1361. is 1 second. A value of 0 will fill all segments, making pages as large as
  1362. possible. A value of 1 will effectively use 1 packet-per-page in most
  1363. situations, giving a small seek granularity at the cost of additional container
  1364. overhead.
  1365. @item -serial_offset @var{value}
  1366. Serial value from which to set the streams serial number.
  1367. Setting it to different and sufficiently large values ensures that the produced
  1368. ogg files can be safely chained.
  1369. @end table
  1370. @anchor{segment}
  1371. @section segment, stream_segment, ssegment
  1372. Basic stream segmenter.
  1373. This muxer outputs streams to a number of separate files of nearly
  1374. fixed duration. Output filename pattern can be set in a fashion
  1375. similar to @ref{image2}, or by using a @code{strftime} template if
  1376. the @option{strftime} option is enabled.
  1377. @code{stream_segment} is a variant of the muxer used to write to
  1378. streaming output formats, i.e. which do not require global headers,
  1379. and is recommended for outputting e.g. to MPEG transport stream segments.
  1380. @code{ssegment} is a shorter alias for @code{stream_segment}.
  1381. Every segment starts with a keyframe of the selected reference stream,
  1382. which is set through the @option{reference_stream} option.
  1383. Note that if you want accurate splitting for a video file, you need to
  1384. make the input key frames correspond to the exact splitting times
  1385. expected by the segmenter, or the segment muxer will start the new
  1386. segment with the key frame found next after the specified start
  1387. time.
  1388. The segment muxer works best with a single constant frame rate video.
  1389. Optionally it can generate a list of the created segments, by setting
  1390. the option @var{segment_list}. The list type is specified by the
  1391. @var{segment_list_type} option. The entry filenames in the segment
  1392. list are set by default to the basename of the corresponding segment
  1393. files.
  1394. See also the @ref{hls} muxer, which provides a more specific
  1395. implementation for HLS segmentation.
  1396. @subsection Options
  1397. The segment muxer supports the following options:
  1398. @table @option
  1399. @item increment_tc @var{1|0}
  1400. if set to @code{1}, increment timecode between each segment
  1401. If this is selected, the input need to have
  1402. a timecode in the first video stream. Default value is
  1403. @code{0}.
  1404. @item reference_stream @var{specifier}
  1405. Set the reference stream, as specified by the string @var{specifier}.
  1406. If @var{specifier} is set to @code{auto}, the reference is chosen
  1407. automatically. Otherwise it must be a stream specifier (see the ``Stream
  1408. specifiers'' chapter in the ffmpeg manual) which specifies the
  1409. reference stream. The default value is @code{auto}.
  1410. @item segment_format @var{format}
  1411. Override the inner container format, by default it is guessed by the filename
  1412. extension.
  1413. @item segment_format_options @var{options_list}
  1414. Set output format options using a :-separated list of key=value
  1415. parameters. Values containing the @code{:} special character must be
  1416. escaped.
  1417. @item segment_list @var{name}
  1418. Generate also a listfile named @var{name}. If not specified no
  1419. listfile is generated.
  1420. @item segment_list_flags @var{flags}
  1421. Set flags affecting the segment list generation.
  1422. It currently supports the following flags:
  1423. @table @samp
  1424. @item cache
  1425. Allow caching (only affects M3U8 list files).
  1426. @item live
  1427. Allow live-friendly file generation.
  1428. @end table
  1429. @item segment_list_size @var{size}
  1430. Update the list file so that it contains at most @var{size}
  1431. segments. If 0 the list file will contain all the segments. Default
  1432. value is 0.
  1433. @item segment_list_entry_prefix @var{prefix}
  1434. Prepend @var{prefix} to each entry. Useful to generate absolute paths.
  1435. By default no prefix is applied.
  1436. @item segment_list_type @var{type}
  1437. Select the listing format.
  1438. The following values are recognized:
  1439. @table @samp
  1440. @item flat
  1441. Generate a flat list for the created segments, one segment per line.
  1442. @item csv, ext
  1443. Generate a list for the created segments, one segment per line,
  1444. each line matching the format (comma-separated values):
  1445. @example
  1446. @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
  1447. @end example
  1448. @var{segment_filename} is the name of the output file generated by the
  1449. muxer according to the provided pattern. CSV escaping (according to
  1450. RFC4180) is applied if required.
  1451. @var{segment_start_time} and @var{segment_end_time} specify
  1452. the segment start and end time expressed in seconds.
  1453. A list file with the suffix @code{".csv"} or @code{".ext"} will
  1454. auto-select this format.
  1455. @samp{ext} is deprecated in favor or @samp{csv}.
  1456. @item ffconcat
  1457. Generate an ffconcat file for the created segments. The resulting file
  1458. can be read using the FFmpeg @ref{concat} demuxer.
  1459. A list file with the suffix @code{".ffcat"} or @code{".ffconcat"} will
  1460. auto-select this format.
  1461. @item m3u8
  1462. Generate an extended M3U8 file, version 3, compliant with
  1463. @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming}.
  1464. A list file with the suffix @code{".m3u8"} will auto-select this format.
  1465. @end table
  1466. If not specified the type is guessed from the list file name suffix.
  1467. @item segment_time @var{time}
  1468. Set segment duration to @var{time}, the value must be a duration
  1469. specification. Default value is "2". See also the
  1470. @option{segment_times} option.
  1471. Note that splitting may not be accurate, unless you force the
  1472. reference stream key-frames at the given time. See the introductory
  1473. notice and the examples below.
  1474. @item segment_atclocktime @var{1|0}
  1475. If set to "1" split at regular clock time intervals starting from 00:00
  1476. o'clock. The @var{time} value specified in @option{segment_time} is
  1477. used for setting the length of the splitting interval.
  1478. For example with @option{segment_time} set to "900" this makes it possible
  1479. to create files at 12:00 o'clock, 12:15, 12:30, etc.
  1480. Default value is "0".
  1481. @item segment_clocktime_offset @var{duration}
  1482. Delay the segment splitting times with the specified duration when using
  1483. @option{segment_atclocktime}.
  1484. For example with @option{segment_time} set to "900" and
  1485. @option{segment_clocktime_offset} set to "300" this makes it possible to
  1486. create files at 12:05, 12:20, 12:35, etc.
  1487. Default value is "0".
  1488. @item segment_clocktime_wrap_duration @var{duration}
  1489. Force the segmenter to only start a new segment if a packet reaches the muxer
  1490. within the specified duration after the segmenting clock time. This way you
  1491. can make the segmenter more resilient to backward local time jumps, such as
  1492. leap seconds or transition to standard time from daylight savings time.
  1493. Default is the maximum possible duration which means starting a new segment
  1494. regardless of the elapsed time since the last clock time.
  1495. @item segment_time_delta @var{delta}
  1496. Specify the accuracy time when selecting the start time for a
  1497. segment, expressed as a duration specification. Default value is "0".
  1498. When delta is specified a key-frame will start a new segment if its
  1499. PTS satisfies the relation:
  1500. @example
  1501. PTS >= start_time - time_delta
  1502. @end example
  1503. This option is useful when splitting video content, which is always
  1504. split at GOP boundaries, in case a key frame is found just before the
  1505. specified split time.
  1506. In particular may be used in combination with the @file{ffmpeg} option
  1507. @var{force_key_frames}. The key frame times specified by
  1508. @var{force_key_frames} may not be set accurately because of rounding
  1509. issues, with the consequence that a key frame time may result set just
  1510. before the specified time. For constant frame rate videos a value of
  1511. 1/(2*@var{frame_rate}) should address the worst case mismatch between
  1512. the specified time and the time set by @var{force_key_frames}.
  1513. @item segment_times @var{times}
  1514. Specify a list of split points. @var{times} contains a list of comma
  1515. separated duration specifications, in increasing order. See also
  1516. the @option{segment_time} option.
  1517. @item segment_frames @var{frames}
  1518. Specify a list of split video frame numbers. @var{frames} contains a
  1519. list of comma separated integer numbers, in increasing order.
  1520. This option specifies to start a new segment whenever a reference
  1521. stream key frame is found and the sequential number (starting from 0)
  1522. of the frame is greater or equal to the next value in the list.
  1523. @item segment_wrap @var{limit}
  1524. Wrap around segment index once it reaches @var{limit}.
  1525. @item segment_start_number @var{number}
  1526. Set the sequence number of the first segment. Defaults to @code{0}.
  1527. @item strftime @var{1|0}
  1528. Use the @code{strftime} function to define the name of the new
  1529. segments to write. If this is selected, the output segment name must
  1530. contain a @code{strftime} function template. Default value is
  1531. @code{0}.
  1532. @item break_non_keyframes @var{1|0}
  1533. If enabled, allow segments to start on frames other than keyframes. This
  1534. improves behavior on some players when the time between keyframes is
  1535. inconsistent, but may make things worse on others, and can cause some oddities
  1536. during seeking. Defaults to @code{0}.
  1537. @item reset_timestamps @var{1|0}
  1538. Reset timestamps at the beginning of each segment, so that each segment
  1539. will start with near-zero timestamps. It is meant to ease the playback
  1540. of the generated segments. May not work with some combinations of
  1541. muxers/codecs. It is set to @code{0} by default.
  1542. @item initial_offset @var{offset}
  1543. Specify timestamp offset to apply to the output packet timestamps. The
  1544. argument must be a time duration specification, and defaults to 0.
  1545. @item write_empty_segments @var{1|0}
  1546. If enabled, write an empty segment if there are no packets during the period a
  1547. segment would usually span. Otherwise, the segment will be filled with the next
  1548. packet written. Defaults to @code{0}.
  1549. @end table
  1550. Make sure to require a closed GOP when encoding and to set the GOP
  1551. size to fit your segment time constraint.
  1552. @subsection Examples
  1553. @itemize
  1554. @item
  1555. Remux the content of file @file{in.mkv} to a list of segments
  1556. @file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
  1557. generated segments to @file{out.list}:
  1558. @example
  1559. ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
  1560. @end example
  1561. @item
  1562. Segment input and set output format options for the output segments:
  1563. @example
  1564. ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
  1565. @end example
  1566. @item
  1567. Segment the input file according to the split points specified by the
  1568. @var{segment_times} option:
  1569. @example
  1570. 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
  1571. @end example
  1572. @item
  1573. Use the @command{ffmpeg} @option{force_key_frames}
  1574. option to force key frames in the input at the specified location, together
  1575. with the segment option @option{segment_time_delta} to account for
  1576. possible roundings operated when setting key frame times.
  1577. @example
  1578. ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
  1579. -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
  1580. @end example
  1581. In order to force key frames on the input file, transcoding is
  1582. required.
  1583. @item
  1584. Segment the input file by splitting the input file according to the
  1585. frame numbers sequence specified with the @option{segment_frames} option:
  1586. @example
  1587. ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
  1588. @end example
  1589. @item
  1590. Convert the @file{in.mkv} to TS segments using the @code{libx264}
  1591. and @code{aac} encoders:
  1592. @example
  1593. ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
  1594. @end example
  1595. @item
  1596. Segment the input file, and create an M3U8 live playlist (can be used
  1597. as live HLS source):
  1598. @example
  1599. ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
  1600. -segment_list_flags +live -segment_time 10 out%03d.mkv
  1601. @end example
  1602. @end itemize
  1603. @section smoothstreaming
  1604. Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
  1605. @table @option
  1606. @item window_size
  1607. Specify the number of fragments kept in the manifest. Default 0 (keep all).
  1608. @item extra_window_size
  1609. Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
  1610. @item lookahead_count
  1611. Specify the number of lookahead fragments. Default 2.
  1612. @item min_frag_duration
  1613. Specify the minimum fragment duration (in microseconds). Default 5000000.
  1614. @item remove_at_exit
  1615. Specify whether to remove all fragments when finished. Default 0 (do not remove).
  1616. @end table
  1617. @anchor{fifo}
  1618. @section fifo
  1619. The fifo pseudo-muxer allows the separation of encoding and muxing by using
  1620. first-in-first-out queue and running the actual muxer in a separate thread. This
  1621. is especially useful in combination with the @ref{tee} muxer and can be used to
  1622. send data to several destinations with different reliability/writing speed/latency.
  1623. API users should be aware that callback functions (interrupt_callback,
  1624. io_open and io_close) used within its AVFormatContext must be thread-safe.
  1625. The behavior of the fifo muxer if the queue fills up or if the output fails is
  1626. selectable,
  1627. @itemize @bullet
  1628. @item
  1629. output can be transparently restarted with configurable delay between retries
  1630. based on real time or time of the processed stream.
  1631. @item
  1632. encoding can be blocked during temporary failure, or continue transparently
  1633. dropping packets in case fifo queue fills up.
  1634. @end itemize
  1635. @table @option
  1636. @item fifo_format
  1637. Specify the format name. Useful if it cannot be guessed from the
  1638. output name suffix.
  1639. @item queue_size
  1640. Specify size of the queue (number of packets). Default value is 60.
  1641. @item format_opts
  1642. Specify format options for the underlying muxer. Muxer options can be specified
  1643. as a list of @var{key}=@var{value} pairs separated by ':'.
  1644. @item drop_pkts_on_overflow @var{bool}
  1645. If set to 1 (true), in case the fifo queue fills up, packets will be dropped
  1646. rather than blocking the encoder. This makes it possible to continue streaming without
  1647. delaying the input, at the cost of omitting part of the stream. By default
  1648. this option is set to 0 (false), so in such cases the encoder will be blocked
  1649. until the muxer processes some of the packets and none of them is lost.
  1650. @item attempt_recovery @var{bool}
  1651. If failure occurs, attempt to recover the output. This is especially useful
  1652. when used with network output, since it makes it possible to restart streaming transparently.
  1653. By default this option is set to 0 (false).
  1654. @item max_recovery_attempts
  1655. Sets maximum number of successive unsuccessful recovery attempts after which
  1656. the output fails permanently. By default this option is set to 0 (unlimited).
  1657. @item recovery_wait_time @var{duration}
  1658. Waiting time before the next recovery attempt after previous unsuccessful
  1659. recovery attempt. Default value is 5 seconds.
  1660. @item recovery_wait_streamtime @var{bool}
  1661. If set to 0 (false), the real time is used when waiting for the recovery
  1662. attempt (i.e. the recovery will be attempted after at least
  1663. recovery_wait_time seconds).
  1664. If set to 1 (true), the time of the processed stream is taken into account
  1665. instead (i.e. the recovery will be attempted after at least @var{recovery_wait_time}
  1666. seconds of the stream is omitted).
  1667. By default, this option is set to 0 (false).
  1668. @item recover_any_error @var{bool}
  1669. If set to 1 (true), recovery will be attempted regardless of type of the error
  1670. causing the failure. By default this option is set to 0 (false) and in case of
  1671. certain (usually permanent) errors the recovery is not attempted even when
  1672. @var{attempt_recovery} is set to 1.
  1673. @item restart_with_keyframe @var{bool}
  1674. Specify whether to wait for the keyframe after recovering from
  1675. queue overflow or failure. This option is set to 0 (false) by default.
  1676. @end table
  1677. @subsection Examples
  1678. @itemize
  1679. @item
  1680. Stream something to rtmp server, continue processing the stream at real-time
  1681. rate even in case of temporary failure (network outage) and attempt to recover
  1682. streaming every second indefinitely.
  1683. @example
  1684. ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
  1685. -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
  1686. @end example
  1687. @end itemize
  1688. @anchor{tee}
  1689. @section tee
  1690. The tee muxer can be used to write the same data to several outputs, such as files or streams.
  1691. It can be used, for example, to stream a video over a network and save it to disk at the same time.
  1692. It is different from specifying several outputs to the @command{ffmpeg}
  1693. command-line tool. With the tee muxer, the audio and video data will be encoded only once.
  1694. With conventional multiple outputs, multiple encoding operations in parallel are initiated,
  1695. which can be a very expensive process. The tee muxer is not useful when using the libavformat API
  1696. directly because it is then possible to feed the same packets to several muxers directly.
  1697. Since the tee muxer does not represent any particular output format, ffmpeg cannot auto-select
  1698. output streams. So all streams intended for output must be specified using @code{-map}. See
  1699. the examples below.
  1700. Some encoders may need different options depending on the output format;
  1701. the auto-detection of this can not work with the tee muxer, so they need to be explicitly specified.
  1702. The main example is the @option{global_header} flag.
  1703. The slave outputs are specified in the file name given to the muxer,
  1704. separated by '|'. If any of the slave name contains the '|' separator,
  1705. leading or trailing spaces or any special character, those must be
  1706. escaped (see @ref{quoting_and_escaping,,the "Quoting and escaping"
  1707. section in the ffmpeg-utils(1) manual,ffmpeg-utils}).
  1708. @subsection Options
  1709. @table @option
  1710. @item use_fifo @var{bool}
  1711. If set to 1, slave outputs will be processed in separate threads using the @ref{fifo}
  1712. muxer. This allows to compensate for different speed/latency/reliability of
  1713. outputs and setup transparent recovery. By default this feature is turned off.
  1714. @item fifo_options
  1715. Options to pass to fifo pseudo-muxer instances. See @ref{fifo}.
  1716. @end table
  1717. Muxer options can be specified for each slave by prepending them as a list of
  1718. @var{key}=@var{value} pairs separated by ':', between square brackets. If
  1719. the options values contain a special character or the ':' separator, they
  1720. must be escaped; note that this is a second level escaping.
  1721. The following special options are also recognized:
  1722. @table @option
  1723. @item f
  1724. Specify the format name. Required if it cannot be guessed from the
  1725. output URL.
  1726. @item bsfs[/@var{spec}]
  1727. Specify a list of bitstream filters to apply to the specified
  1728. output.
  1729. It is possible to specify to which streams a given bitstream filter
  1730. applies, by appending a stream specifier to the option separated by
  1731. @code{/}. @var{spec} must be a stream specifier (see @ref{Format
  1732. stream specifiers}).
  1733. If the stream specifier is not specified, the bitstream filters will be
  1734. applied to all streams in the output. This will cause that output operation
  1735. to fail if the output contains streams to which the bitstream filter cannot
  1736. be applied e.g. @code{h264_mp4toannexb} being applied to an output containing an audio stream.
  1737. Options for a bitstream filter must be specified in the form of @code{opt=value}.
  1738. Several bitstream filters can be specified, separated by ",".
  1739. @item use_fifo @var{bool}
  1740. This allows to override tee muxer use_fifo option for individual slave muxer.
  1741. @item fifo_options
  1742. This allows to override tee muxer fifo_options for individual slave muxer.
  1743. See @ref{fifo}.
  1744. @item select
  1745. Select the streams that should be mapped to the slave output,
  1746. specified by a stream specifier. If not specified, this defaults to
  1747. all the mapped streams. This will cause that output operation to fail
  1748. if the output format does not accept all mapped streams.
  1749. You may use multiple stream specifiers separated by commas (@code{,}) e.g.: @code{a:0,v}
  1750. @item onfail
  1751. Specify behaviour on output failure. This can be set to either @code{abort} (which is
  1752. default) or @code{ignore}. @code{abort} will cause whole process to fail in case of failure
  1753. on this slave output. @code{ignore} will ignore failure on this output, so other outputs
  1754. will continue without being affected.
  1755. @end table
  1756. @subsection Examples
  1757. @itemize
  1758. @item
  1759. Encode something and both archive it in a WebM file and stream it
  1760. as MPEG-TS over UDP:
  1761. @example
  1762. ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
  1763. "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
  1764. @end example
  1765. @item
  1766. As above, but continue streaming even if output to local file fails
  1767. (for example local drive fills up):
  1768. @example
  1769. ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
  1770. "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
  1771. @end example
  1772. @item
  1773. Use @command{ffmpeg} to encode the input, and send the output
  1774. to three different destinations. The @code{dump_extra} bitstream
  1775. filter is used to add extradata information to all the output video
  1776. keyframes packets, as requested by the MPEG-TS format. The select
  1777. option is applied to @file{out.aac} in order to make it contain only
  1778. audio packets.
  1779. @example
  1780. ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
  1781. -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
  1782. @end example
  1783. @item
  1784. As above, but select only stream @code{a:1} for the audio output. Note
  1785. that a second level escaping must be performed, as ":" is a special
  1786. character used to separate options.
  1787. @example
  1788. ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
  1789. -f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
  1790. @end example
  1791. @end itemize
  1792. @section webm_dash_manifest
  1793. WebM DASH Manifest muxer.
  1794. This muxer implements the WebM DASH Manifest specification to generate the DASH
  1795. manifest XML. It also supports manifest generation for DASH live streams.
  1796. For more information see:
  1797. @itemize @bullet
  1798. @item
  1799. WebM DASH Specification: @url{https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification}
  1800. @item
  1801. ISO DASH Specification: @url{http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip}
  1802. @end itemize
  1803. @subsection Options
  1804. This muxer supports the following options:
  1805. @table @option
  1806. @item adaptation_sets
  1807. This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
  1808. unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
  1809. audio and video streams. Any number of adaptation sets can be added using this option.
  1810. @item live
  1811. Set this to 1 to create a live stream DASH Manifest. Default: 0.
  1812. @item chunk_start_index
  1813. Start index of the first chunk. This will go in the @samp{startNumber} attribute
  1814. of the @samp{SegmentTemplate} element in the manifest. Default: 0.
  1815. @item chunk_duration_ms
  1816. Duration of each chunk in milliseconds. This will go in the @samp{duration}
  1817. attribute of the @samp{SegmentTemplate} element in the manifest. Default: 1000.
  1818. @item utc_timing_url
  1819. URL of the page that will return the UTC timestamp in ISO format. This will go
  1820. in the @samp{value} attribute of the @samp{UTCTiming} element in the manifest.
  1821. Default: None.
  1822. @item time_shift_buffer_depth
  1823. Smallest time (in seconds) shifting buffer for which any Representation is
  1824. guaranteed to be available. This will go in the @samp{timeShiftBufferDepth}
  1825. attribute of the @samp{MPD} element. Default: 60.
  1826. @item minimum_update_period
  1827. Minimum update period (in seconds) of the manifest. This will go in the
  1828. @samp{minimumUpdatePeriod} attribute of the @samp{MPD} element. Default: 0.
  1829. @end table
  1830. @subsection Example
  1831. @example
  1832. ffmpeg -f webm_dash_manifest -i video1.webm \
  1833. -f webm_dash_manifest -i video2.webm \
  1834. -f webm_dash_manifest -i audio1.webm \
  1835. -f webm_dash_manifest -i audio2.webm \
  1836. -map 0 -map 1 -map 2 -map 3 \
  1837. -c copy \
  1838. -f webm_dash_manifest \
  1839. -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
  1840. manifest.xml
  1841. @end example
  1842. @section webm_chunk
  1843. WebM Live Chunk Muxer.
  1844. This muxer writes out WebM headers and chunks as separate files which can be
  1845. consumed by clients that support WebM Live streams via DASH.
  1846. @subsection Options
  1847. This muxer supports the following options:
  1848. @table @option
  1849. @item chunk_start_index
  1850. Index of the first chunk (defaults to 0).
  1851. @item header
  1852. Filename of the header where the initialization data will be written.
  1853. @item audio_chunk_duration
  1854. Duration of each audio chunk in milliseconds (defaults to 5000).
  1855. @end table
  1856. @subsection Example
  1857. @example
  1858. ffmpeg -f v4l2 -i /dev/video0 \
  1859. -f alsa -i hw:0 \
  1860. -map 0:0 \
  1861. -c:v libvpx-vp9 \
  1862. -s 640x360 -keyint_min 30 -g 30 \
  1863. -f webm_chunk \
  1864. -header webm_live_video_360.hdr \
  1865. -chunk_start_index 1 \
  1866. webm_live_video_360_%d.chk \
  1867. -map 1:0 \
  1868. -c:a libvorbis \
  1869. -b:a 128k \
  1870. -f webm_chunk \
  1871. -header webm_live_audio_128.hdr \
  1872. -chunk_start_index 1 \
  1873. -audio_chunk_duration 1000 \
  1874. webm_live_audio_128_%d.chk
  1875. @end example
  1876. @c man end MUXERS