ffmpeg.texi 109 KB

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  1. \input texinfo @c -*- texinfo -*-
  2. @documentencoding UTF-8
  3. @settitle ffmpeg Documentation
  4. @titlepage
  5. @center @titlefont{ffmpeg Documentation}
  6. @end titlepage
  7. @top
  8. @contents
  9. @chapter Synopsis
  10. ffmpeg [@var{global_options}] @{[@var{input_file_options}] -i @file{input_url}@} ... @{[@var{output_file_options}] @file{output_url}@} ...
  11. @chapter Description
  12. @c man begin DESCRIPTION
  13. @command{ffmpeg} is a universal media converter. It can read a wide variety of
  14. inputs - including live grabbing/recording devices - filter, and transcode them
  15. into a plethora of output formats.
  16. @command{ffmpeg} reads from an arbitrary number of input "files" (which can be regular
  17. files, pipes, network streams, grabbing devices, etc.), specified by the
  18. @code{-i} option, and writes to an arbitrary number of output "files", which are
  19. specified by a plain output url. Anything found on the command line which
  20. cannot be interpreted as an option is considered to be an output url.
  21. Each input or output url can, in principle, contain any number of streams of
  22. different types (video/audio/subtitle/attachment/data). The allowed number and/or
  23. types of streams may be limited by the container format. Selecting which
  24. streams from which inputs will go into which output is either done automatically
  25. or with the @code{-map} option (see the Stream selection chapter).
  26. To refer to input files in options, you must use their indices (0-based). E.g.
  27. the first input file is @code{0}, the second is @code{1}, etc. Similarly, streams
  28. within a file are referred to by their indices. E.g. @code{2:3} refers to the
  29. fourth stream in the third input file. Also see the Stream specifiers chapter.
  30. As a general rule, options are applied to the next specified
  31. file. Therefore, order is important, and you can have the same
  32. option on the command line multiple times. Each occurrence is
  33. then applied to the next input or output file.
  34. Exceptions from this rule are the global options (e.g. verbosity level),
  35. which should be specified first.
  36. Do not mix input and output files -- first specify all input files, then all
  37. output files. Also do not mix options which belong to different files. All
  38. options apply ONLY to the next input or output file and are reset between files.
  39. Some simple examples follow.
  40. @itemize
  41. @item
  42. Convert an input media file to a different format, by re-encoding media streams:
  43. @example
  44. ffmpeg -i input.avi output.mp4
  45. @end example
  46. @item
  47. Set the video bitrate of the output file to 64 kbit/s:
  48. @example
  49. ffmpeg -i input.avi -b:v 64k -bufsize 64k output.mp4
  50. @end example
  51. @item
  52. Force the frame rate of the output file to 24 fps:
  53. @example
  54. ffmpeg -i input.avi -r 24 output.mp4
  55. @end example
  56. @item
  57. Force the frame rate of the input file (valid for raw formats only) to 1 fps and
  58. the frame rate of the output file to 24 fps:
  59. @example
  60. ffmpeg -r 1 -i input.m2v -r 24 output.mp4
  61. @end example
  62. @end itemize
  63. The format option may be needed for raw input files.
  64. @c man end DESCRIPTION
  65. @chapter Detailed description
  66. @c man begin DETAILED DESCRIPTION
  67. The transcoding process in @command{ffmpeg} for each output can be described by
  68. the following diagram:
  69. @verbatim
  70. _______ ______________
  71. | | | |
  72. | input | demuxer | encoded data | decoder
  73. | file | ---------> | packets | -----+
  74. |_______| |______________| |
  75. v
  76. _________
  77. | |
  78. | decoded |
  79. | frames |
  80. |_________|
  81. ________ ______________ |
  82. | | | | |
  83. | output | <-------- | encoded data | <----+
  84. | file | muxer | packets | encoder
  85. |________| |______________|
  86. @end verbatim
  87. @command{ffmpeg} calls the libavformat library (containing demuxers) to read
  88. input files and get packets containing encoded data from them. When there are
  89. multiple input files, @command{ffmpeg} tries to keep them synchronized by
  90. tracking lowest timestamp on any active input stream.
  91. Encoded packets are then passed to the decoder (unless streamcopy is selected
  92. for the stream, see further for a description). The decoder produces
  93. uncompressed frames (raw video/PCM audio/...) which can be processed further by
  94. filtering (see next section). After filtering, the frames are passed to the
  95. encoder, which encodes them and outputs encoded packets. Finally, those are
  96. passed to the muxer, which writes the encoded packets to the output file.
  97. @section Filtering
  98. Before encoding, @command{ffmpeg} can process raw audio and video frames using
  99. filters from the libavfilter library. Several chained filters form a filter
  100. graph. @command{ffmpeg} distinguishes between two types of filtergraphs:
  101. simple and complex.
  102. @subsection Simple filtergraphs
  103. Simple filtergraphs are those that have exactly one input and output, both of
  104. the same type. In the above diagram they can be represented by simply inserting
  105. an additional step between decoding and encoding:
  106. @verbatim
  107. _________ ______________
  108. | | | |
  109. | decoded | | encoded data |
  110. | frames |\ _ | packets |
  111. |_________| \ /||______________|
  112. \ __________ /
  113. simple _\|| | / encoder
  114. filtergraph | filtered |/
  115. | frames |
  116. |__________|
  117. @end verbatim
  118. Simple filtergraphs are configured with the per-stream @option{-filter} option
  119. (with @option{-vf} and @option{-af} aliases for video and audio respectively).
  120. A simple filtergraph for video can look for example like this:
  121. @verbatim
  122. _______ _____________ _______ ________
  123. | | | | | | | |
  124. | input | ---> | deinterlace | ---> | scale | ---> | output |
  125. |_______| |_____________| |_______| |________|
  126. @end verbatim
  127. Note that some filters change frame properties but not frame contents. E.g. the
  128. @code{fps} filter in the example above changes number of frames, but does not
  129. touch the frame contents. Another example is the @code{setpts} filter, which
  130. only sets timestamps and otherwise passes the frames unchanged.
  131. @subsection Complex filtergraphs
  132. Complex filtergraphs are those which cannot be described as simply a linear
  133. processing chain applied to one stream. This is the case, for example, when the graph has
  134. more than one input and/or output, or when output stream type is different from
  135. input. They can be represented with the following diagram:
  136. @verbatim
  137. _________
  138. | |
  139. | input 0 |\ __________
  140. |_________| \ | |
  141. \ _________ /| output 0 |
  142. \ | | / |__________|
  143. _________ \| complex | /
  144. | | | |/
  145. | input 1 |---->| filter |\
  146. |_________| | | \ __________
  147. /| graph | \ | |
  148. / | | \| output 1 |
  149. _________ / |_________| |__________|
  150. | | /
  151. | input 2 |/
  152. |_________|
  153. @end verbatim
  154. Complex filtergraphs are configured with the @option{-filter_complex} option.
  155. Note that this option is global, since a complex filtergraph, by its nature,
  156. cannot be unambiguously associated with a single stream or file.
  157. The @option{-lavfi} option is equivalent to @option{-filter_complex}.
  158. A trivial example of a complex filtergraph is the @code{overlay} filter, which
  159. has two video inputs and one video output, containing one video overlaid on top
  160. of the other. Its audio counterpart is the @code{amix} filter.
  161. @section Stream copy
  162. Stream copy is a mode selected by supplying the @code{copy} parameter to the
  163. @option{-codec} option. It makes @command{ffmpeg} omit the decoding and encoding
  164. step for the specified stream, so it does only demuxing and muxing. It is useful
  165. for changing the container format or modifying container-level metadata. The
  166. diagram above will, in this case, simplify to this:
  167. @verbatim
  168. _______ ______________ ________
  169. | | | | | |
  170. | input | demuxer | encoded data | muxer | output |
  171. | file | ---------> | packets | -------> | file |
  172. |_______| |______________| |________|
  173. @end verbatim
  174. Since there is no decoding or encoding, it is very fast and there is no quality
  175. loss. However, it might not work in some cases because of many factors. Applying
  176. filters is obviously also impossible, since filters work on uncompressed data.
  177. @section Loopback decoders
  178. While decoders are normally associated with demuxer streams, it is also possible
  179. to create "loopback" decoders that decode the output from some encoder and allow
  180. it to be fed back to complex filtergraphs. This is done with the @code{-dec}
  181. directive, which takes as a parameter the index of the output stream that should
  182. be decoded. Every such directive creates a new loopback decoder, indexed with
  183. successive integers starting at zero. These indices should then be used to refer
  184. to loopback decoders in complex filtergraph link labels, as described in the
  185. documentation for @option{-filter_complex}.
  186. Decoding AVOptions can be passed to loopback decoders by placing them before
  187. @code{-dec}, analogously to input/output options.
  188. E.g. the following example:
  189. @example
  190. ffmpeg -i INPUT \
  191. -map 0:v:0 -c:v libx264 -crf 45 -f null - \
  192. -threads 3 -dec 0:0 \
  193. -filter_complex '[0:v][dec:0]hstack[stack]' \
  194. -map '[stack]' -c:v ffv1 OUTPUT
  195. @end example
  196. reads an input video and
  197. @itemize
  198. @item
  199. (line 2) encodes it with @code{libx264} at low quality;
  200. @item
  201. (line 3) decodes this encoded stream using 3 threads;
  202. @item
  203. (line 4) places decoded video side by side with the original input video;
  204. @item
  205. (line 5) combined video is then losslessly encoded and written into
  206. @file{OUTPUT}.
  207. @end itemize
  208. @c man end DETAILED DESCRIPTION
  209. @chapter Stream selection
  210. @c man begin STREAM SELECTION
  211. @command{ffmpeg} provides the @code{-map} option for manual control of stream selection in each
  212. output file. Users can skip @code{-map} and let ffmpeg perform automatic stream selection as
  213. described below. The @code{-vn / -an / -sn / -dn} options can be used to skip inclusion of
  214. video, audio, subtitle and data streams respectively, whether manually mapped or automatically
  215. selected, except for those streams which are outputs of complex filtergraphs.
  216. @section Description
  217. The sub-sections that follow describe the various rules that are involved in stream selection.
  218. The examples that follow next show how these rules are applied in practice.
  219. While every effort is made to accurately reflect the behavior of the program, FFmpeg is under
  220. continuous development and the code may have changed since the time of this writing.
  221. @subsection Automatic stream selection
  222. In the absence of any map options for a particular output file, ffmpeg inspects the output
  223. format to check which type of streams can be included in it, viz. video, audio and/or
  224. subtitles. For each acceptable stream type, ffmpeg will pick one stream, when available,
  225. from among all the inputs.
  226. It will select that stream based upon the following criteria:
  227. @itemize
  228. @item
  229. for video, it is the stream with the highest resolution,
  230. @item
  231. for audio, it is the stream with the most channels,
  232. @item
  233. for subtitles, it is the first subtitle stream found but there's a caveat.
  234. The output format's default subtitle encoder can be either text-based or image-based,
  235. and only a subtitle stream of the same type will be chosen.
  236. @end itemize
  237. In the case where several streams of the same type rate equally, the stream with the lowest
  238. index is chosen.
  239. Data or attachment streams are not automatically selected and can only be included
  240. using @code{-map}.
  241. @subsection Manual stream selection
  242. When @code{-map} is used, only user-mapped streams are included in that output file,
  243. with one possible exception for filtergraph outputs described below.
  244. @subsection Complex filtergraphs
  245. If there are any complex filtergraph output streams with unlabeled pads, they will be added
  246. to the first output file. This will lead to a fatal error if the stream type is not supported
  247. by the output format. In the absence of the map option, the inclusion of these streams leads
  248. to the automatic stream selection of their types being skipped. If map options are present,
  249. these filtergraph streams are included in addition to the mapped streams.
  250. Complex filtergraph output streams with labeled pads must be mapped once and exactly once.
  251. @subsection Stream handling
  252. Stream handling is independent of stream selection, with an exception for subtitles described
  253. below. Stream handling is set via the @code{-codec} option addressed to streams within a
  254. specific @emph{output} file. In particular, codec options are applied by ffmpeg after the
  255. stream selection process and thus do not influence the latter. If no @code{-codec} option is
  256. specified for a stream type, ffmpeg will select the default encoder registered by the output
  257. file muxer.
  258. An exception exists for subtitles. If a subtitle encoder is specified for an output file, the
  259. first subtitle stream found of any type, text or image, will be included. ffmpeg does not validate
  260. if the specified encoder can convert the selected stream or if the converted stream is acceptable
  261. within the output format. This applies generally as well: when the user sets an encoder manually,
  262. the stream selection process cannot check if the encoded stream can be muxed into the output file.
  263. If it cannot, ffmpeg will abort and @emph{all} output files will fail to be processed.
  264. @section Examples
  265. The following examples illustrate the behavior, quirks and limitations of ffmpeg's stream
  266. selection methods.
  267. They assume the following three input files.
  268. @verbatim
  269. input file 'A.avi'
  270. stream 0: video 640x360
  271. stream 1: audio 2 channels
  272. input file 'B.mp4'
  273. stream 0: video 1920x1080
  274. stream 1: audio 2 channels
  275. stream 2: subtitles (text)
  276. stream 3: audio 5.1 channels
  277. stream 4: subtitles (text)
  278. input file 'C.mkv'
  279. stream 0: video 1280x720
  280. stream 1: audio 2 channels
  281. stream 2: subtitles (image)
  282. @end verbatim
  283. @subsubheading Example: automatic stream selection
  284. @example
  285. ffmpeg -i A.avi -i B.mp4 out1.mkv out2.wav -map 1:a -c:a copy out3.mov
  286. @end example
  287. There are three output files specified, and for the first two, no @code{-map} options
  288. are set, so ffmpeg will select streams for these two files automatically.
  289. @file{out1.mkv} is a Matroska container file and accepts video, audio and subtitle streams,
  290. so ffmpeg will try to select one of each type.@*
  291. For video, it will select @code{stream 0} from @file{B.mp4}, which has the highest
  292. resolution among all the input video streams.@*
  293. For audio, it will select @code{stream 3} from @file{B.mp4}, since it has the greatest
  294. number of channels.@*
  295. For subtitles, it will select @code{stream 2} from @file{B.mp4}, which is the first subtitle
  296. stream from among @file{A.avi} and @file{B.mp4}.
  297. @file{out2.wav} accepts only audio streams, so only @code{stream 3} from @file{B.mp4} is
  298. selected.
  299. For @file{out3.mov}, since a @code{-map} option is set, no automatic stream selection will
  300. occur. The @code{-map 1:a} option will select all audio streams from the second input
  301. @file{B.mp4}. No other streams will be included in this output file.
  302. For the first two outputs, all included streams will be transcoded. The encoders chosen will
  303. be the default ones registered by each output format, which may not match the codec of the
  304. selected input streams.
  305. For the third output, codec option for audio streams has been set
  306. to @code{copy}, so no decoding-filtering-encoding operations will occur, or @emph{can} occur.
  307. Packets of selected streams shall be conveyed from the input file and muxed within the output
  308. file.
  309. @subsubheading Example: automatic subtitles selection
  310. @example
  311. ffmpeg -i C.mkv out1.mkv -c:s dvdsub -an out2.mkv
  312. @end example
  313. Although @file{out1.mkv} is a Matroska container file which accepts subtitle streams, only a
  314. video and audio stream shall be selected. The subtitle stream of @file{C.mkv} is image-based
  315. and the default subtitle encoder of the Matroska muxer is text-based, so a transcode operation
  316. for the subtitles is expected to fail and hence the stream isn't selected. However, in
  317. @file{out2.mkv}, a subtitle encoder is specified in the command and so, the subtitle stream is
  318. selected, in addition to the video stream. The presence of @code{-an} disables audio stream
  319. selection for @file{out2.mkv}.
  320. @subsubheading Example: unlabeled filtergraph outputs
  321. @example
  322. ffmpeg -i A.avi -i C.mkv -i B.mp4 -filter_complex "overlay" out1.mp4 out2.srt
  323. @end example
  324. A filtergraph is setup here using the @code{-filter_complex} option and consists of a single
  325. video filter. The @code{overlay} filter requires exactly two video inputs, but none are
  326. specified, so the first two available video streams are used, those of @file{A.avi} and
  327. @file{C.mkv}. The output pad of the filter has no label and so is sent to the first output file
  328. @file{out1.mp4}. Due to this, automatic selection of the video stream is skipped, which would
  329. have selected the stream in @file{B.mp4}. The audio stream with most channels viz. @code{stream 3}
  330. in @file{B.mp4}, is chosen automatically. No subtitle stream is chosen however, since the MP4
  331. format has no default subtitle encoder registered, and the user hasn't specified a subtitle encoder.
  332. The 2nd output file, @file{out2.srt}, only accepts text-based subtitle streams. So, even though
  333. the first subtitle stream available belongs to @file{C.mkv}, it is image-based and hence skipped.
  334. The selected stream, @code{stream 2} in @file{B.mp4}, is the first text-based subtitle stream.
  335. @subsubheading Example: labeled filtergraph outputs
  336. @example
  337. ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0[outv];overlay;aresample" \
  338. -map '[outv]' -an out1.mp4 \
  339. out2.mkv \
  340. -map '[outv]' -map 1:a:0 out3.mkv
  341. @end example
  342. The above command will fail, as the output pad labelled @code{[outv]} has been mapped twice.
  343. None of the output files shall be processed.
  344. @example
  345. ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0[outv];overlay;aresample" \
  346. -an out1.mp4 \
  347. out2.mkv \
  348. -map 1:a:0 out3.mkv
  349. @end example
  350. This command above will also fail as the hue filter output has a label, @code{[outv]},
  351. and hasn't been mapped anywhere.
  352. The command should be modified as follows,
  353. @example
  354. ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0,split=2[outv1][outv2];overlay;aresample" \
  355. -map '[outv1]' -an out1.mp4 \
  356. out2.mkv \
  357. -map '[outv2]' -map 1:a:0 out3.mkv
  358. @end example
  359. The video stream from @file{B.mp4} is sent to the hue filter, whose output is cloned once using
  360. the split filter, and both outputs labelled. Then a copy each is mapped to the first and third
  361. output files.
  362. The overlay filter, requiring two video inputs, uses the first two unused video streams. Those
  363. are the streams from @file{A.avi} and @file{C.mkv}. The overlay output isn't labelled, so it is
  364. sent to the first output file @file{out1.mp4}, regardless of the presence of the @code{-map} option.
  365. The aresample filter is sent the first unused audio stream, that of @file{A.avi}. Since this filter
  366. output is also unlabelled, it too is mapped to the first output file. The presence of @code{-an}
  367. only suppresses automatic or manual stream selection of audio streams, not outputs sent from
  368. filtergraphs. Both these mapped streams shall be ordered before the mapped stream in @file{out1.mp4}.
  369. The video, audio and subtitle streams mapped to @code{out2.mkv} are entirely determined by
  370. automatic stream selection.
  371. @file{out3.mkv} consists of the cloned video output from the hue filter and the first audio
  372. stream from @file{B.mp4}.
  373. @*
  374. @c man end STREAM SELECTION
  375. @chapter Options
  376. @c man begin OPTIONS
  377. @include fftools-common-opts.texi
  378. @section Main options
  379. @table @option
  380. @item -f @var{fmt} (@emph{input/output})
  381. Force input or output file format. The format is normally auto detected for input
  382. files and guessed from the file extension for output files, so this option is not
  383. needed in most cases.
  384. @item -i @var{url} (@emph{input})
  385. input file url
  386. @item -y (@emph{global})
  387. Overwrite output files without asking.
  388. @item -n (@emph{global})
  389. Do not overwrite output files, and exit immediately if a specified
  390. output file already exists.
  391. @item -stream_loop @var{number} (@emph{input})
  392. Set number of times input stream shall be looped. Loop 0 means no loop,
  393. loop -1 means infinite loop.
  394. @item -recast_media (@emph{global})
  395. Allow forcing a decoder of a different media type than the one
  396. detected or designated by the demuxer. Useful for decoding media
  397. data muxed as data streams.
  398. @item -c[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
  399. @itemx -codec[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
  400. Select an encoder (when used before an output file) or a decoder (when used
  401. before an input file) for one or more streams. @var{codec} is the name of a
  402. decoder/encoder or a special value @code{copy} (output only) to indicate that
  403. the stream is not to be re-encoded.
  404. For example
  405. @example
  406. ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT
  407. @end example
  408. encodes all video streams with libx264 and copies all audio streams.
  409. For each stream, the last matching @code{c} option is applied, so
  410. @example
  411. ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT
  412. @end example
  413. will copy all the streams except the second video, which will be encoded with
  414. libx264, and the 138th audio, which will be encoded with libvorbis.
  415. @item -t @var{duration} (@emph{input/output})
  416. When used as an input option (before @code{-i}), limit the @var{duration} of
  417. data read from the input file.
  418. When used as an output option (before an output url), stop writing the
  419. output after its duration reaches @var{duration}.
  420. @var{duration} must be a time duration specification,
  421. see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
  422. -to and -t are mutually exclusive and -t has priority.
  423. @item -to @var{position} (@emph{input/output})
  424. Stop writing the output or reading the input at @var{position}.
  425. @var{position} must be a time duration specification,
  426. see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
  427. -to and -t are mutually exclusive and -t has priority.
  428. @item -fs @var{limit_size} (@emph{output})
  429. Set the file size limit, expressed in bytes. No further chunk of bytes is written
  430. after the limit is exceeded. The size of the output file is slightly more than the
  431. requested file size.
  432. @item -ss @var{position} (@emph{input/output})
  433. When used as an input option (before @code{-i}), seeks in this input file to
  434. @var{position}. Note that in most formats it is not possible to seek exactly,
  435. so @command{ffmpeg} will seek to the closest seek point before @var{position}.
  436. When transcoding and @option{-accurate_seek} is enabled (the default), this
  437. extra segment between the seek point and @var{position} will be decoded and
  438. discarded. When doing stream copy or when @option{-noaccurate_seek} is used, it
  439. will be preserved.
  440. When used as an output option (before an output url), decodes but discards
  441. input until the timestamps reach @var{position}.
  442. @var{position} must be a time duration specification,
  443. see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
  444. @item -sseof @var{position} (@emph{input})
  445. Like the @code{-ss} option but relative to the "end of file". That is negative
  446. values are earlier in the file, 0 is at EOF.
  447. @item -isync @var{input_index} (@emph{input})
  448. Assign an input as a sync source.
  449. This will take the difference between the start times of the target and reference inputs and
  450. offset the timestamps of the target file by that difference. The source timestamps of the two
  451. inputs should derive from the same clock source for expected results. If @code{copyts} is set
  452. then @code{start_at_zero} must also be set. If either of the inputs has no starting timestamp
  453. then no sync adjustment is made.
  454. Acceptable values are those that refer to a valid ffmpeg input index. If the sync reference is
  455. the target index itself or @var{-1}, then no adjustment is made to target timestamps. A sync
  456. reference may not itself be synced to any other input.
  457. Default value is @var{-1}.
  458. @item -itsoffset @var{offset} (@emph{input})
  459. Set the input time offset.
  460. @var{offset} must be a time duration specification,
  461. see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
  462. The offset is added to the timestamps of the input files. Specifying
  463. a positive offset means that the corresponding streams are delayed by
  464. the time duration specified in @var{offset}.
  465. @item -itsscale @var{scale} (@emph{input,per-stream})
  466. Rescale input timestamps. @var{scale} should be a floating point number.
  467. @item -timestamp @var{date} (@emph{output})
  468. Set the recording timestamp in the container.
  469. @var{date} must be a date specification,
  470. see @ref{date syntax,,the Date section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
  471. @item -metadata[:metadata_specifier] @var{key}=@var{value} (@emph{output,per-metadata})
  472. Set a metadata key/value pair.
  473. An optional @var{metadata_specifier} may be given to set metadata
  474. on streams, chapters or programs. See @code{-map_metadata}
  475. documentation for details.
  476. This option overrides metadata set with @code{-map_metadata}. It is
  477. also possible to delete metadata by using an empty value.
  478. For example, for setting the title in the output file:
  479. @example
  480. ffmpeg -i in.avi -metadata title="my title" out.flv
  481. @end example
  482. To set the language of the first audio stream:
  483. @example
  484. ffmpeg -i INPUT -metadata:s:a:0 language=eng OUTPUT
  485. @end example
  486. @item -disposition[:stream_specifier] @var{value} (@emph{output,per-stream})
  487. Sets the disposition for a stream.
  488. By default, the disposition is copied from the input stream, unless the output
  489. stream this option applies to is fed by a complex filtergraph - in that case the
  490. disposition is unset by default.
  491. @var{value} is a sequence of items separated by '+' or '-'. The first item may
  492. also be prefixed with '+' or '-', in which case this option modifies the default
  493. value. Otherwise (the first item is not prefixed) this options overrides the
  494. default value. A '+' prefix adds the given disposition, '-' removes it. It is
  495. also possible to clear the disposition by setting it to 0.
  496. If no @code{-disposition} options were specified for an output file, ffmpeg will
  497. automatically set the 'default' disposition on the first stream of each type,
  498. when there are multiple streams of this type in the output file and no stream of
  499. that type is already marked as default.
  500. The @code{-dispositions} option lists the known dispositions.
  501. For example, to make the second audio stream the default stream:
  502. @example
  503. ffmpeg -i in.mkv -c copy -disposition:a:1 default out.mkv
  504. @end example
  505. To make the second subtitle stream the default stream and remove the default
  506. disposition from the first subtitle stream:
  507. @example
  508. ffmpeg -i in.mkv -c copy -disposition:s:0 0 -disposition:s:1 default out.mkv
  509. @end example
  510. To add an embedded cover/thumbnail:
  511. @example
  512. ffmpeg -i in.mp4 -i IMAGE -map 0 -map 1 -c copy -c:v:1 png -disposition:v:1 attached_pic out.mp4
  513. @end example
  514. Not all muxers support embedded thumbnails, and those who do, only support a few formats, like JPEG or PNG.
  515. @item -program [title=@var{title}:][program_num=@var{program_num}:]st=@var{stream}[:st=@var{stream}...] (@emph{output})
  516. Creates a program with the specified @var{title}, @var{program_num} and adds the specified
  517. @var{stream}(s) to it.
  518. @item -stream_group [map=@var{input_file_id}=@var{stream_group}][type=@var{type}:]st=@var{stream}[:st=@var{stream}][:stg=@var{stream_group}][:id=@var{stream_group_id}...] (@emph{output})
  519. Creates a stream group of the specified @var{type} and @var{stream_group_id}, or by
  520. @var{map}ping an input group, adding the specified @var{stream}(s) and/or previously
  521. defined @var{stream_group}(s) to it.
  522. @var{type} can be one of the following:
  523. @table @option
  524. @item iamf_audio_element
  525. Groups @var{stream}s that belong to the same IAMF Audio Element
  526. For this group @var{type}, the following options are available
  527. @table @option
  528. @item audio_element_type
  529. The Audio Element type. The following values are supported:
  530. @table @option
  531. @item channel
  532. Scalable channel audio representation
  533. @item scene
  534. Ambisonics representation
  535. @end table
  536. @item demixing
  537. Demixing information used to reconstruct a scalable channel audio representation.
  538. This option must be separated from the rest with a ',', and takes the following
  539. key=value options
  540. @table @option
  541. @item parameter_id
  542. An identifier parameters blocks in frames may refer to
  543. @item dmixp_mode
  544. A pre-defined combination of demixing parameters
  545. @end table
  546. @item recon_gain
  547. Recon gain information used to reconstruct a scalable channel audio representation.
  548. This option must be separated from the rest with a ',', and takes the following
  549. key=value options
  550. @table @option
  551. @item parameter_id
  552. An identifier parameters blocks in frames may refer to
  553. @end table
  554. @item layer
  555. A layer defining a Channel Layout in the Audio Element.
  556. This option must be separated from the rest with a ','. Several ',' separated entries
  557. can be defined, and at least one must be set.
  558. It takes the following ":"-separated key=value options
  559. @table @option
  560. @item ch_layout
  561. The layer's channel layout
  562. @item flags
  563. The following flags are available:
  564. @table @option
  565. @item recon_gain
  566. Wether to signal if recon_gain is present as metadata in parameter blocks within frames
  567. @end table
  568. @item output_gain
  569. @item output_gain_flags
  570. Which channels output_gain applies to. The following flags are available:
  571. @table @option
  572. @item FL
  573. @item FR
  574. @item BL
  575. @item BR
  576. @item TFL
  577. @item TFR
  578. @end table
  579. @item ambisonics_mode
  580. The ambisonics mode. This has no effect if audio_element_type is set to channel.
  581. The following values are supported:
  582. @table @option
  583. @item mono
  584. Each ambisonics channel is coded as an individual mono stream in the group
  585. @end table
  586. @end table
  587. @item default_w
  588. Default weight value
  589. @end table
  590. @item iamf_mix_presentation
  591. Groups @var{stream}s that belong to all IAMF Audio Element the same
  592. IAMF Mix Presentation references
  593. For this group @var{type}, the following options are available
  594. @table @option
  595. @item submix
  596. A sub-mix within the Mix Presentation.
  597. This option must be separated from the rest with a ','. Several ',' separated entries
  598. can be defined, and at least one must be set.
  599. It takes the following ":"-separated key=value options
  600. @table @option
  601. @item parameter_id
  602. An identifier parameters blocks in frames may refer to, for post-processing the mixed
  603. audio signal to generate the audio signal for playback
  604. @item parameter_rate
  605. The sample rate duration fields in parameters blocks in frames that refer to this
  606. @var{parameter_id} are expressed as
  607. @item default_mix_gain
  608. Default mix gain value to apply when there are no parameter blocks sharing the same
  609. @var{parameter_id} for a given frame
  610. @item element
  611. References an Audio Element used in this Mix Presentation to generate the final output
  612. audio signal for playback.
  613. This option must be separated from the rest with a '|'. Several '|' separated entries
  614. can be defined, and at least one must be set.
  615. It takes the following ":"-separated key=value options:
  616. @table @option
  617. @item stg
  618. The @var{stream_group_id} for an Audio Element which this sub-mix refers to
  619. @item parameter_id
  620. An identifier parameters blocks in frames may refer to, for applying any processing to
  621. the referenced and rendered Audio Element before being summed with other processed Audio
  622. Elements
  623. @item parameter_rate
  624. The sample rate duration fields in parameters blocks in frames that refer to this
  625. @var{parameter_id} are expressed as
  626. @item default_mix_gain
  627. Default mix gain value to apply when there are no parameter blocks sharing the same
  628. @var{parameter_id} for a given frame
  629. @item annotations
  630. A key=value string describing the sub-mix element where "key" is a string conforming to
  631. BCP-47 that specifies the language for the "value" string. "key" must be the same as the
  632. one in the mix's @var{annotations}
  633. @item headphones_rendering_mode
  634. Indicates whether the input channel-based Audio Element is rendered to stereo loudspeakers
  635. or spatialized with a binaural renderer when played back on headphones.
  636. This has no effect if the referenced Audio Element's @var{audio_element_type} is set to
  637. channel.
  638. The following values are supported:
  639. @table @option
  640. @item stereo
  641. @item binaural
  642. @end table
  643. @end table
  644. @item layout
  645. Specifies the layouts for this sub-mix on which the loudness information was measured.
  646. This option must be separated from the rest with a '|'. Several '|' separated entries
  647. can be defined, and at least one must be set.
  648. It takes the following ":"-separated key=value options:
  649. @table @option
  650. @item layout_type
  651. @table @option
  652. @item loudspeakers
  653. The layout follows the loudspeaker sound system convention of ITU-2051-3.
  654. @item binaural
  655. The layout is binaural.
  656. @end table
  657. @item sound_system
  658. Channel layout matching one of Sound Systems A to J of ITU-2051-3, plus 7.1.2 and 3.1.2
  659. This has no effect if @var{layout_type} is set to binaural.
  660. @item integrated_loudness
  661. The program integrated loudness information, as defined in ITU-1770-4.
  662. @item digital_peak
  663. The digital (sampled) peak value of the audio signal, as defined in ITU-1770-4.
  664. @item true_peak
  665. The true peak of the audio signal, as defined in ITU-1770-4.
  666. @item dialog_anchored_loudness
  667. The Dialogue loudness information, as defined in ITU-1770-4.
  668. @item album_anchored_loudness
  669. The Album loudness information, as defined in ITU-1770-4.
  670. @end table
  671. @end table
  672. @item annotations
  673. A key=value string string describing the mix where "key" is a string conforming to BCP-47
  674. that specifies the language for the "value" string. "key" must be the same as the ones in
  675. all sub-mix element's @var{annotations}s
  676. @end table
  677. @end table
  678. E.g. to create an scalable 5.1 IAMF file from several WAV input files
  679. @example
  680. ffmpeg -i front.wav -i back.wav -i center.wav -i lfe.wav
  681. -map 0:0 -map 1:0 -map 2:0 -map 3:0 -c:a opus
  682. -stream_group type=iamf_audio_element:id=1:st=0:st=1:st=2:st=3,
  683. demixing=parameter_id=998,
  684. recon_gain=parameter_id=101,
  685. layer=ch_layout=stereo,
  686. layer=ch_layout=5.1,
  687. -stream_group type=iamf_mix_presentation:id=2:stg=0:annotations=en-us=Mix_Presentation,
  688. submix=parameter_id=100:parameter_rate=48000|element=stg=0:parameter_id=100:annotations=en-us=Scalable_Submix|layout=sound_system=stereo|layout=sound_system=5.1
  689. -streamid 0:0 -streamid 1:1 -streamid 2:2 -streamid 3:3 output.iamf
  690. @end example
  691. To copy the two stream groups (Audio Element and Mix Presentation) from an input IAMF file with four
  692. streams into an mp4 output
  693. @example
  694. ffmpeg -i input.iamf -c:a copy -stream_group map=0=0:st=0:st=1:st=2:st=3 -stream_group map=0=1:stg=0
  695. -streamid 0:0 -streamid 1:1 -streamid 2:2 -streamid 3:3 output.mp4
  696. @end example
  697. @item -target @var{type} (@emph{output})
  698. Specify target file type (@code{vcd}, @code{svcd}, @code{dvd}, @code{dv},
  699. @code{dv50}). @var{type} may be prefixed with @code{pal-}, @code{ntsc-} or
  700. @code{film-} to use the corresponding standard. All the format options
  701. (bitrate, codecs, buffer sizes) are then set automatically. You can just type:
  702. @example
  703. ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
  704. @end example
  705. Nevertheless you can specify additional options as long as you know
  706. they do not conflict with the standard, as in:
  707. @example
  708. ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
  709. @end example
  710. The parameters set for each target are as follows.
  711. @strong{VCD}
  712. @example
  713. @var{pal}:
  714. -f vcd -muxrate 1411200 -muxpreload 0.44 -packetsize 2324
  715. -s 352x288 -r 25
  716. -codec:v mpeg1video -g 15 -b:v 1150k -maxrate:v 1150k -minrate:v 1150k -bufsize:v 327680
  717. -ar 44100 -ac 2
  718. -codec:a mp2 -b:a 224k
  719. @var{ntsc}:
  720. -f vcd -muxrate 1411200 -muxpreload 0.44 -packetsize 2324
  721. -s 352x240 -r 30000/1001
  722. -codec:v mpeg1video -g 18 -b:v 1150k -maxrate:v 1150k -minrate:v 1150k -bufsize:v 327680
  723. -ar 44100 -ac 2
  724. -codec:a mp2 -b:a 224k
  725. @var{film}:
  726. -f vcd -muxrate 1411200 -muxpreload 0.44 -packetsize 2324
  727. -s 352x240 -r 24000/1001
  728. -codec:v mpeg1video -g 18 -b:v 1150k -maxrate:v 1150k -minrate:v 1150k -bufsize:v 327680
  729. -ar 44100 -ac 2
  730. -codec:a mp2 -b:a 224k
  731. @end example
  732. @strong{SVCD}
  733. @example
  734. @var{pal}:
  735. -f svcd -packetsize 2324
  736. -s 480x576 -pix_fmt yuv420p -r 25
  737. -codec:v mpeg2video -g 15 -b:v 2040k -maxrate:v 2516k -minrate:v 0 -bufsize:v 1835008 -scan_offset 1
  738. -ar 44100
  739. -codec:a mp2 -b:a 224k
  740. @var{ntsc}:
  741. -f svcd -packetsize 2324
  742. -s 480x480 -pix_fmt yuv420p -r 30000/1001
  743. -codec:v mpeg2video -g 18 -b:v 2040k -maxrate:v 2516k -minrate:v 0 -bufsize:v 1835008 -scan_offset 1
  744. -ar 44100
  745. -codec:a mp2 -b:a 224k
  746. @var{film}:
  747. -f svcd -packetsize 2324
  748. -s 480x480 -pix_fmt yuv420p -r 24000/1001
  749. -codec:v mpeg2video -g 18 -b:v 2040k -maxrate:v 2516k -minrate:v 0 -bufsize:v 1835008 -scan_offset 1
  750. -ar 44100
  751. -codec:a mp2 -b:a 224k
  752. @end example
  753. @strong{DVD}
  754. @example
  755. @var{pal}:
  756. -f dvd -muxrate 10080k -packetsize 2048
  757. -s 720x576 -pix_fmt yuv420p -r 25
  758. -codec:v mpeg2video -g 15 -b:v 6000k -maxrate:v 9000k -minrate:v 0 -bufsize:v 1835008
  759. -ar 48000
  760. -codec:a ac3 -b:a 448k
  761. @var{ntsc}:
  762. -f dvd -muxrate 10080k -packetsize 2048
  763. -s 720x480 -pix_fmt yuv420p -r 30000/1001
  764. -codec:v mpeg2video -g 18 -b:v 6000k -maxrate:v 9000k -minrate:v 0 -bufsize:v 1835008
  765. -ar 48000
  766. -codec:a ac3 -b:a 448k
  767. @var{film}:
  768. -f dvd -muxrate 10080k -packetsize 2048
  769. -s 720x480 -pix_fmt yuv420p -r 24000/1001
  770. -codec:v mpeg2video -g 18 -b:v 6000k -maxrate:v 9000k -minrate:v 0 -bufsize:v 1835008
  771. -ar 48000
  772. -codec:a ac3 -b:a 448k
  773. @end example
  774. @strong{DV}
  775. @example
  776. @var{pal}:
  777. -f dv
  778. -s 720x576 -pix_fmt yuv420p -r 25
  779. -ar 48000 -ac 2
  780. @var{ntsc}:
  781. -f dv
  782. -s 720x480 -pix_fmt yuv411p -r 30000/1001
  783. -ar 48000 -ac 2
  784. @var{film}:
  785. -f dv
  786. -s 720x480 -pix_fmt yuv411p -r 24000/1001
  787. -ar 48000 -ac 2
  788. @end example
  789. The @code{dv50} target is identical to the @code{dv} target except that the pixel format set is @code{yuv422p} for all three standards.
  790. Any user-set value for a parameter above will override the target preset value. In that case, the output may
  791. not comply with the target standard.
  792. @item -dn (@emph{input/output})
  793. As an input option, blocks all data streams of a file from being filtered or
  794. being automatically selected or mapped for any output. See @code{-discard}
  795. option to disable streams individually.
  796. As an output option, disables data recording i.e. automatic selection or
  797. mapping of any data stream. For full manual control see the @code{-map}
  798. option.
  799. @item -dframes @var{number} (@emph{output})
  800. Set the number of data frames to output. This is an obsolete alias for
  801. @code{-frames:d}, which you should use instead.
  802. @item -frames[:@var{stream_specifier}] @var{framecount} (@emph{output,per-stream})
  803. Stop writing to the stream after @var{framecount} frames.
  804. @item -q[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
  805. @itemx -qscale[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
  806. Use fixed quality scale (VBR). The meaning of @var{q}/@var{qscale} is
  807. codec-dependent.
  808. If @var{qscale} is used without a @var{stream_specifier} then it applies only
  809. to the video stream, this is to maintain compatibility with previous behavior
  810. and as specifying the same codec specific value to 2 different codecs that is
  811. audio and video generally is not what is intended when no stream_specifier is
  812. used.
  813. @anchor{filter_option}
  814. @item -filter[:@var{stream_specifier}] @var{filtergraph} (@emph{output,per-stream})
  815. Create the filtergraph specified by @var{filtergraph} and use it to
  816. filter the stream.
  817. @var{filtergraph} is a description of the filtergraph to apply to
  818. the stream, and must have a single input and a single output of the
  819. same type of the stream. In the filtergraph, the input is associated
  820. to the label @code{in}, and the output to the label @code{out}. See
  821. the ffmpeg-filters manual for more information about the filtergraph
  822. syntax.
  823. See the @ref{filter_complex_option,,-filter_complex option} if you
  824. want to create filtergraphs with multiple inputs and/or outputs.
  825. @item -reinit_filter[:@var{stream_specifier}] @var{integer} (@emph{input,per-stream})
  826. This boolean option determines if the filtergraph(s) to which this stream is fed gets
  827. reinitialized when input frame parameters change mid-stream. This option is enabled by
  828. default as most video and all audio filters cannot handle deviation in input frame properties.
  829. Upon reinitialization, existing filter state is lost, like e.g. the frame count @code{n}
  830. reference available in some filters. Any frames buffered at time of reinitialization are lost.
  831. The properties where a change triggers reinitialization are,
  832. for video, frame resolution or pixel format;
  833. for audio, sample format, sample rate, channel count or channel layout.
  834. @item -filter_threads @var{nb_threads} (@emph{global})
  835. Defines how many threads are used to process a filter pipeline. Each pipeline
  836. will produce a thread pool with this many threads available for parallel processing.
  837. The default is the number of available CPUs.
  838. @item -pre[:@var{stream_specifier}] @var{preset_name} (@emph{output,per-stream})
  839. Specify the preset for matching stream(s).
  840. @item -stats (@emph{global})
  841. Print encoding progress/statistics. It is on by default, to explicitly
  842. disable it you need to specify @code{-nostats}.
  843. @item -stats_period @var{time} (@emph{global})
  844. Set period at which encoding progress/statistics are updated. Default is 0.5 seconds.
  845. @item -progress @var{url} (@emph{global})
  846. Send program-friendly progress information to @var{url}.
  847. Progress information is written periodically and at the end of
  848. the encoding process. It is made of "@var{key}=@var{value}" lines. @var{key}
  849. consists of only alphanumeric characters. The last key of a sequence of
  850. progress information is always "progress".
  851. The update period is set using @code{-stats_period}.
  852. @anchor{stdin option}
  853. @item -stdin
  854. Enable interaction on standard input. On by default unless standard input is
  855. used as an input. To explicitly disable interaction you need to specify
  856. @code{-nostdin}.
  857. Disabling interaction on standard input is useful, for example, if
  858. ffmpeg is in the background process group. Roughly the same result can
  859. be achieved with @code{ffmpeg ... < /dev/null} but it requires a
  860. shell.
  861. @item -debug_ts (@emph{global})
  862. Print timestamp/latency information. It is off by default. This option is
  863. mostly useful for testing and debugging purposes, and the output
  864. format may change from one version to another, so it should not be
  865. employed by portable scripts.
  866. See also the option @code{-fdebug ts}.
  867. @item -attach @var{filename} (@emph{output})
  868. Add an attachment to the output file. This is supported by a few formats
  869. like Matroska for e.g. fonts used in rendering subtitles. Attachments
  870. are implemented as a specific type of stream, so this option will add
  871. a new stream to the file. It is then possible to use per-stream options
  872. on this stream in the usual way. Attachment streams created with this
  873. option will be created after all the other streams (i.e. those created
  874. with @code{-map} or automatic mappings).
  875. Note that for Matroska you also have to set the mimetype metadata tag:
  876. @example
  877. ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv
  878. @end example
  879. (assuming that the attachment stream will be third in the output file).
  880. @item -dump_attachment[:@var{stream_specifier}] @var{filename} (@emph{input,per-stream})
  881. Extract the matching attachment stream into a file named @var{filename}. If
  882. @var{filename} is empty, then the value of the @code{filename} metadata tag
  883. will be used.
  884. E.g. to extract the first attachment to a file named 'out.ttf':
  885. @example
  886. ffmpeg -dump_attachment:t:0 out.ttf -i INPUT
  887. @end example
  888. To extract all attachments to files determined by the @code{filename} tag:
  889. @example
  890. ffmpeg -dump_attachment:t "" -i INPUT
  891. @end example
  892. Technical note -- attachments are implemented as codec extradata, so this
  893. option can actually be used to extract extradata from any stream, not just
  894. attachments.
  895. @end table
  896. @section Video Options
  897. @table @option
  898. @item -vframes @var{number} (@emph{output})
  899. Set the number of video frames to output. This is an obsolete alias for
  900. @code{-frames:v}, which you should use instead.
  901. @item -r[:@var{stream_specifier}] @var{fps} (@emph{input/output,per-stream})
  902. Set frame rate (Hz value, fraction or abbreviation).
  903. As an input option, ignore any timestamps stored in the file and instead
  904. generate timestamps assuming constant frame rate @var{fps}.
  905. This is not the same as the @option{-framerate} option used for some input formats
  906. like image2 or v4l2 (it used to be the same in older versions of FFmpeg).
  907. If in doubt use @option{-framerate} instead of the input option @option{-r}.
  908. As an output option:
  909. @table @option
  910. @item video encoding
  911. Duplicate or drop frames right before encoding them to achieve constant output
  912. frame rate @var{fps}.
  913. @item video streamcopy
  914. Indicate to the muxer that @var{fps} is the stream frame rate. No data is
  915. dropped or duplicated in this case. This may produce invalid files if @var{fps}
  916. does not match the actual stream frame rate as determined by packet timestamps.
  917. See also the @code{setts} bitstream filter.
  918. @end table
  919. @item -fpsmax[:@var{stream_specifier}] @var{fps} (@emph{output,per-stream})
  920. Set maximum frame rate (Hz value, fraction or abbreviation).
  921. Clamps output frame rate when output framerate is auto-set and is higher than this value.
  922. Useful in batch processing or when input framerate is wrongly detected as very high.
  923. It cannot be set together with @code{-r}. It is ignored during streamcopy.
  924. @item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream})
  925. Set frame size.
  926. As an input option, this is a shortcut for the @option{video_size} private
  927. option, recognized by some demuxers for which the frame size is either not
  928. stored in the file or is configurable -- e.g. raw video or video grabbers.
  929. As an output option, this inserts the @code{scale} video filter to the
  930. @emph{end} of the corresponding filtergraph. Please use the @code{scale} filter
  931. directly to insert it at the beginning or some other place.
  932. The format is @samp{wxh} (default - same as source).
  933. @item -aspect[:@var{stream_specifier}] @var{aspect} (@emph{output,per-stream})
  934. Set the video display aspect ratio specified by @var{aspect}.
  935. @var{aspect} can be a floating point number string, or a string of the
  936. form @var{num}:@var{den}, where @var{num} and @var{den} are the
  937. numerator and denominator of the aspect ratio. For example "4:3",
  938. "16:9", "1.3333", and "1.7777" are valid argument values.
  939. If used together with @option{-vcodec copy}, it will affect the aspect ratio
  940. stored at container level, but not the aspect ratio stored in encoded
  941. frames, if it exists.
  942. @item -display_rotation[:@var{stream_specifier}] @var{rotation} (@emph{input,per-stream})
  943. Set video rotation metadata.
  944. @var{rotation} is a decimal number specifying the amount in degree by
  945. which the video should be rotated counter-clockwise before being
  946. displayed.
  947. This option overrides the rotation/display transform metadata stored in
  948. the file, if any. When the video is being transcoded (rather than
  949. copied) and @code{-autorotate} is enabled, the video will be rotated at
  950. the filtering stage. Otherwise, the metadata will be written into the
  951. output file if the muxer supports it.
  952. If the @code{-display_hflip} and/or @code{-display_vflip} options are
  953. given, they are applied after the rotation specified by this option.
  954. @item -display_hflip[:@var{stream_specifier}] (@emph{input,per-stream})
  955. Set whether on display the image should be horizontally flipped.
  956. See the @code{-display_rotation} option for more details.
  957. @item -display_vflip[:@var{stream_specifier}] (@emph{input,per-stream})
  958. Set whether on display the image should be vertically flipped.
  959. See the @code{-display_rotation} option for more details.
  960. @item -vn (@emph{input/output})
  961. As an input option, blocks all video streams of a file from being filtered or
  962. being automatically selected or mapped for any output. See @code{-discard}
  963. option to disable streams individually.
  964. As an output option, disables video recording i.e. automatic selection or
  965. mapping of any video stream. For full manual control see the @code{-map}
  966. option.
  967. @item -vcodec @var{codec} (@emph{output})
  968. Set the video codec. This is an alias for @code{-codec:v}.
  969. @item -pass[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
  970. Select the pass number (1 or 2). It is used to do two-pass
  971. video encoding. The statistics of the video are recorded in the first
  972. pass into a log file (see also the option -passlogfile),
  973. and in the second pass that log file is used to generate the video
  974. at the exact requested bitrate.
  975. On pass 1, you may just deactivate audio and set output to null,
  976. examples for Windows and Unix:
  977. @example
  978. ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
  979. ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null
  980. @end example
  981. @item -passlogfile[:@var{stream_specifier}] @var{prefix} (@emph{output,per-stream})
  982. Set two-pass log file name prefix to @var{prefix}, the default file name
  983. prefix is ``ffmpeg2pass''. The complete file name will be
  984. @file{PREFIX-N.log}, where N is a number specific to the output
  985. stream
  986. @item -vf @var{filtergraph} (@emph{output})
  987. Create the filtergraph specified by @var{filtergraph} and use it to
  988. filter the stream.
  989. This is an alias for @code{-filter:v}, see the @ref{filter_option,,-filter option}.
  990. @item -autorotate
  991. Automatically rotate the video according to file metadata. Enabled by
  992. default, use @option{-noautorotate} to disable it.
  993. @item -autoscale
  994. Automatically scale the video according to the resolution of first frame.
  995. Enabled by default, use @option{-noautoscale} to disable it. When autoscale is
  996. disabled, all output frames of filter graph might not be in the same resolution
  997. and may be inadequate for some encoder/muxer. Therefore, it is not recommended
  998. to disable it unless you really know what you are doing.
  999. Disable autoscale at your own risk.
  1000. @end table
  1001. @section Advanced Video options
  1002. @table @option
  1003. @item -pix_fmt[:@var{stream_specifier}] @var{format} (@emph{input/output,per-stream})
  1004. Set pixel format. Use @code{-pix_fmts} to show all the supported
  1005. pixel formats.
  1006. If the selected pixel format can not be selected, ffmpeg will print a
  1007. warning and select the best pixel format supported by the encoder.
  1008. If @var{pix_fmt} is prefixed by a @code{+}, ffmpeg will exit with an error
  1009. if the requested pixel format can not be selected, and automatic conversions
  1010. inside filtergraphs are disabled.
  1011. If @var{pix_fmt} is a single @code{+}, ffmpeg selects the same pixel format
  1012. as the input (or graph output) and automatic conversions are disabled.
  1013. @item -sws_flags @var{flags} (@emph{input/output})
  1014. Set default flags for the libswscale library. These flags are used by
  1015. automatically inserted @code{scale} filters and those within simple
  1016. filtergraphs, if not overridden within the filtergraph definition.
  1017. See the @ref{scaler_options,,ffmpeg-scaler manual,ffmpeg-scaler} for a list
  1018. of scaler options.
  1019. @item -rc_override[:@var{stream_specifier}] @var{override} (@emph{output,per-stream})
  1020. Rate control override for specific intervals, formatted as "int,int,int"
  1021. list separated with slashes. Two first values are the beginning and
  1022. end frame numbers, last one is quantizer to use if positive, or quality
  1023. factor if negative.
  1024. @item -vstats
  1025. Dump video coding statistics to @file{vstats_HHMMSS.log}. See the
  1026. @ref{vstats_file_format,,vstats file format} section for the format description.
  1027. @item -vstats_file @var{file}
  1028. Dump video coding statistics to @var{file}. See the
  1029. @ref{vstats_file_format,,vstats file format} section for the format description.
  1030. @item -vstats_version @var{file}
  1031. Specify which version of the vstats format to use. Default is @code{2}. See the
  1032. @ref{vstats_file_format,,vstats file format} section for the format description.
  1033. @item -vtag @var{fourcc/tag} (@emph{output})
  1034. Force video tag/fourcc. This is an alias for @code{-tag:v}.
  1035. @item -force_key_frames[:@var{stream_specifier}] @var{time}[,@var{time}...] (@emph{output,per-stream})
  1036. @item -force_key_frames[:@var{stream_specifier}] expr:@var{expr} (@emph{output,per-stream})
  1037. @item -force_key_frames[:@var{stream_specifier}] source (@emph{output,per-stream})
  1038. @var{force_key_frames} can take arguments of the following form:
  1039. @table @option
  1040. @item @var{time}[,@var{time}...]
  1041. If the argument consists of timestamps, ffmpeg will round the specified times to the nearest
  1042. output timestamp as per the encoder time base and force a keyframe at the first frame having
  1043. timestamp equal or greater than the computed timestamp. Note that if the encoder time base is too
  1044. coarse, then the keyframes may be forced on frames with timestamps lower than the specified time.
  1045. The default encoder time base is the inverse of the output framerate but may be set otherwise
  1046. via @code{-enc_time_base}.
  1047. If one of the times is "@code{chapters}[@var{delta}]", it is expanded into
  1048. the time of the beginning of all chapters in the file, shifted by
  1049. @var{delta}, expressed as a time in seconds.
  1050. This option can be useful to ensure that a seek point is present at a
  1051. chapter mark or any other designated place in the output file.
  1052. For example, to insert a key frame at 5 minutes, plus key frames 0.1 second
  1053. before the beginning of every chapter:
  1054. @example
  1055. -force_key_frames 0:05:00,chapters-0.1
  1056. @end example
  1057. @item expr:@var{expr}
  1058. If the argument is prefixed with @code{expr:}, the string @var{expr}
  1059. is interpreted like an expression and is evaluated for each frame. A
  1060. key frame is forced in case the evaluation is non-zero.
  1061. The expression in @var{expr} can contain the following constants:
  1062. @table @option
  1063. @item n
  1064. the number of current processed frame, starting from 0
  1065. @item n_forced
  1066. the number of forced frames
  1067. @item prev_forced_n
  1068. the number of the previous forced frame, it is @code{NAN} when no
  1069. keyframe was forced yet
  1070. @item prev_forced_t
  1071. the time of the previous forced frame, it is @code{NAN} when no
  1072. keyframe was forced yet
  1073. @item t
  1074. the time of the current processed frame
  1075. @end table
  1076. For example to force a key frame every 5 seconds, you can specify:
  1077. @example
  1078. -force_key_frames expr:gte(t,n_forced*5)
  1079. @end example
  1080. To force a key frame 5 seconds after the time of the last forced one,
  1081. starting from second 13:
  1082. @example
  1083. -force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5))
  1084. @end example
  1085. @item source
  1086. If the argument is @code{source}, ffmpeg will force a key frame if
  1087. the current frame being encoded is marked as a key frame in its source.
  1088. In cases where this particular source frame has to be dropped,
  1089. enforce the next available frame to become a key frame instead.
  1090. @end table
  1091. Note that forcing too many keyframes is very harmful for the lookahead
  1092. algorithms of certain encoders: using fixed-GOP options or similar
  1093. would be more efficient.
  1094. @item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream})
  1095. When doing stream copy, copy also non-key frames found at the
  1096. beginning.
  1097. @item -init_hw_device @var{type}[=@var{name}][:@var{device}[,@var{key=value}...]]
  1098. Initialise a new hardware device of type @var{type} called @var{name}, using the
  1099. given device parameters.
  1100. If no name is specified it will receive a default name of the form "@var{type}%d".
  1101. The meaning of @var{device} and the following arguments depends on the
  1102. device type:
  1103. @table @option
  1104. @item cuda
  1105. @var{device} is the number of the CUDA device.
  1106. The following options are recognized:
  1107. @table @option
  1108. @item primary_ctx
  1109. If set to 1, uses the primary device context instead of creating a new one.
  1110. @end table
  1111. Examples:
  1112. @table @emph
  1113. @item -init_hw_device cuda:1
  1114. Choose the second device on the system.
  1115. @item -init_hw_device cuda:0,primary_ctx=1
  1116. Choose the first device and use the primary device context.
  1117. @end table
  1118. @item dxva2
  1119. @var{device} is the number of the Direct3D 9 display adapter.
  1120. @item d3d11va
  1121. @var{device} is the number of the Direct3D 11 display adapter.
  1122. If not specified, it will attempt to use the default Direct3D 11 display adapter
  1123. or the first Direct3D 11 display adapter whose hardware VendorId is specified
  1124. by @samp{vendor_id}.
  1125. Examples:
  1126. @table @emph
  1127. @item -init_hw_device d3d11va
  1128. Create a d3d11va device on the default Direct3D 11 display adapter.
  1129. @item -init_hw_device d3d11va:1
  1130. Create a d3d11va device on the Direct3D 11 display adapter specified by index 1.
  1131. @item -init_hw_device d3d11va:,vendor_id=0x8086
  1132. Create a d3d11va device on the first Direct3D 11 display adapter whose hardware VendorId is 0x8086.
  1133. @end table
  1134. @item vaapi
  1135. @var{device} is either an X11 display name, a DRM render node or a DirectX adapter index.
  1136. If not specified, it will attempt to open the default X11 display (@emph{$DISPLAY})
  1137. and then the first DRM render node (@emph{/dev/dri/renderD128}), or the default
  1138. DirectX adapter on Windows.
  1139. The following options are recognized:
  1140. @table @option
  1141. @item kernel_driver
  1142. When @var{device} is not specified, use this option to specify the name of the kernel
  1143. driver associated with the desired device. This option is available only when
  1144. the hardware acceleration method @emph{drm} and @emph{vaapi} are enabled.
  1145. @end table
  1146. Examples:
  1147. @table @emph
  1148. @item -init_hw_device vaapi
  1149. Create a vaapi device on the default device.
  1150. @item -init_hw_device vaapi:/dev/dri/renderD129
  1151. Create a vaapi device on DRM render node @file{/dev/dri/renderD129}.
  1152. @item -init_hw_device vaapi:1
  1153. Create a vaapi device on DirectX adapter 1.
  1154. @item -init_hw_device vaapi:,kernel_driver=i915
  1155. Create a vaapi device on a device associated with kernel driver @samp{i915}.
  1156. @end table
  1157. @item vdpau
  1158. @var{device} is an X11 display name.
  1159. If not specified, it will attempt to open the default X11 display (@emph{$DISPLAY}).
  1160. @item qsv
  1161. @var{device} selects a value in @samp{MFX_IMPL_*}. Allowed values are:
  1162. @table @option
  1163. @item auto
  1164. @item sw
  1165. @item hw
  1166. @item auto_any
  1167. @item hw_any
  1168. @item hw2
  1169. @item hw3
  1170. @item hw4
  1171. @end table
  1172. If not specified, @samp{auto_any} is used.
  1173. (Note that it may be easier to achieve the desired result for QSV by creating the
  1174. platform-appropriate subdevice (@samp{dxva2} or @samp{d3d11va} or @samp{vaapi}) and then deriving a
  1175. QSV device from that.)
  1176. The following options are recognized:
  1177. @table @option
  1178. @item child_device
  1179. Specify a DRM render node on Linux or DirectX adapter on Windows.
  1180. @item child_device_type
  1181. Choose platform-appropriate subdevice type. On Windows @samp{d3d11va} is used
  1182. as default subdevice type when @code{--enable-libvpl} is specified at configuration time,
  1183. @samp{dxva2} is used as default subdevice type when @code{--enable-libmfx} is specified at
  1184. configuration time. On Linux user can use @samp{vaapi} only as subdevice type.
  1185. @end table
  1186. Examples:
  1187. @table @emph
  1188. @item -init_hw_device qsv:hw,child_device=/dev/dri/renderD129
  1189. Create a QSV device with @samp{MFX_IMPL_HARDWARE} on DRM render node @file{/dev/dri/renderD129}.
  1190. @item -init_hw_device qsv:hw,child_device=1
  1191. Create a QSV device with @samp{MFX_IMPL_HARDWARE} on DirectX adapter 1.
  1192. @item -init_hw_device qsv:hw,child_device_type=d3d11va
  1193. Choose the GPU subdevice with type @samp{d3d11va} and create QSV device with @samp{MFX_IMPL_HARDWARE}.
  1194. @item -init_hw_device qsv:hw,child_device_type=dxva2
  1195. Choose the GPU subdevice with type @samp{dxva2} and create QSV device with @samp{MFX_IMPL_HARDWARE}.
  1196. @item -init_hw_device qsv:hw,child_device=1,child_device_type=d3d11va
  1197. Create a QSV device with @samp{MFX_IMPL_HARDWARE} on DirectX adapter 1 with subdevice type @samp{d3d11va}.
  1198. @item -init_hw_device vaapi=va:/dev/dri/renderD129 -init_hw_device qsv=hw1@@@var{va}
  1199. Create a VAAPI device called @samp{va} on @file{/dev/dri/renderD129}, then derive a QSV device called @samp{hw1}
  1200. from device @samp{va}.
  1201. @end table
  1202. @item opencl
  1203. @var{device} selects the platform and device as @emph{platform_index.device_index}.
  1204. The set of devices can also be filtered using the key-value pairs to find only
  1205. devices matching particular platform or device strings.
  1206. The strings usable as filters are:
  1207. @table @option
  1208. @item platform_profile
  1209. @item platform_version
  1210. @item platform_name
  1211. @item platform_vendor
  1212. @item platform_extensions
  1213. @item device_name
  1214. @item device_vendor
  1215. @item driver_version
  1216. @item device_version
  1217. @item device_profile
  1218. @item device_extensions
  1219. @item device_type
  1220. @end table
  1221. The indices and filters must together uniquely select a device.
  1222. Examples:
  1223. @table @emph
  1224. @item -init_hw_device opencl:0.1
  1225. Choose the second device on the first platform.
  1226. @item -init_hw_device opencl:,device_name=Foo9000
  1227. Choose the device with a name containing the string @emph{Foo9000}.
  1228. @item -init_hw_device opencl:1,device_type=gpu,device_extensions=cl_khr_fp16
  1229. Choose the GPU device on the second platform supporting the @emph{cl_khr_fp16}
  1230. extension.
  1231. @end table
  1232. @item vulkan
  1233. If @var{device} is an integer, it selects the device by its index in a
  1234. system-dependent list of devices. If @var{device} is any other string, it
  1235. selects the first device with a name containing that string as a substring.
  1236. The following options are recognized:
  1237. @table @option
  1238. @item debug
  1239. If set to 1, enables the validation layer, if installed.
  1240. @item linear_images
  1241. If set to 1, images allocated by the hwcontext will be linear and locally mappable.
  1242. @item instance_extensions
  1243. A plus separated list of additional instance extensions to enable.
  1244. @item device_extensions
  1245. A plus separated list of additional device extensions to enable.
  1246. @end table
  1247. Examples:
  1248. @table @emph
  1249. @item -init_hw_device vulkan:1
  1250. Choose the second device on the system.
  1251. @item -init_hw_device vulkan:RADV
  1252. Choose the first device with a name containing the string @emph{RADV}.
  1253. @item -init_hw_device vulkan:0,instance_extensions=VK_KHR_wayland_surface+VK_KHR_xcb_surface
  1254. Choose the first device and enable the Wayland and XCB instance extensions.
  1255. @end table
  1256. @end table
  1257. @item -init_hw_device @var{type}[=@var{name}]@@@var{source}
  1258. Initialise a new hardware device of type @var{type} called @var{name},
  1259. deriving it from the existing device with the name @var{source}.
  1260. @item -init_hw_device list
  1261. List all hardware device types supported in this build of ffmpeg.
  1262. @item -filter_hw_device @var{name}
  1263. Pass the hardware device called @var{name} to all filters in any filter graph.
  1264. This can be used to set the device to upload to with the @code{hwupload} filter,
  1265. or the device to map to with the @code{hwmap} filter. Other filters may also
  1266. make use of this parameter when they require a hardware device. Note that this
  1267. is typically only required when the input is not already in hardware frames -
  1268. when it is, filters will derive the device they require from the context of the
  1269. frames they receive as input.
  1270. This is a global setting, so all filters will receive the same device.
  1271. @item -hwaccel[:@var{stream_specifier}] @var{hwaccel} (@emph{input,per-stream})
  1272. Use hardware acceleration to decode the matching stream(s). The allowed values
  1273. of @var{hwaccel} are:
  1274. @table @option
  1275. @item none
  1276. Do not use any hardware acceleration (the default).
  1277. @item auto
  1278. Automatically select the hardware acceleration method.
  1279. @item vdpau
  1280. Use VDPAU (Video Decode and Presentation API for Unix) hardware acceleration.
  1281. @item dxva2
  1282. Use DXVA2 (DirectX Video Acceleration) hardware acceleration.
  1283. @item d3d11va
  1284. Use D3D11VA (DirectX Video Acceleration) hardware acceleration.
  1285. @item vaapi
  1286. Use VAAPI (Video Acceleration API) hardware acceleration.
  1287. @item qsv
  1288. Use the Intel QuickSync Video acceleration for video transcoding.
  1289. Unlike most other values, this option does not enable accelerated decoding (that
  1290. is used automatically whenever a qsv decoder is selected), but accelerated
  1291. transcoding, without copying the frames into the system memory.
  1292. For it to work, both the decoder and the encoder must support QSV acceleration
  1293. and no filters must be used.
  1294. @end table
  1295. This option has no effect if the selected hwaccel is not available or not
  1296. supported by the chosen decoder.
  1297. Note that most acceleration methods are intended for playback and will not be
  1298. faster than software decoding on modern CPUs. Additionally, @command{ffmpeg}
  1299. will usually need to copy the decoded frames from the GPU memory into the system
  1300. memory, resulting in further performance loss. This option is thus mainly
  1301. useful for testing.
  1302. @item -hwaccel_device[:@var{stream_specifier}] @var{hwaccel_device} (@emph{input,per-stream})
  1303. Select a device to use for hardware acceleration.
  1304. This option only makes sense when the @option{-hwaccel} option is also specified.
  1305. It can either refer to an existing device created with @option{-init_hw_device}
  1306. by name, or it can create a new device as if
  1307. @samp{-init_hw_device} @var{type}:@var{hwaccel_device}
  1308. were called immediately before.
  1309. @item -hwaccels
  1310. List all hardware acceleration components enabled in this build of ffmpeg.
  1311. Actual runtime availability depends on the hardware and its suitable driver
  1312. being installed.
  1313. @item -fix_sub_duration_heartbeat[:@var{stream_specifier}]
  1314. Set a specific output video stream as the heartbeat stream according to which
  1315. to split and push through currently in-progress subtitle upon receipt of a
  1316. random access packet.
  1317. This lowers the latency of subtitles for which the end packet or the following
  1318. subtitle has not yet been received. As a drawback, this will most likely lead
  1319. to duplication of subtitle events in order to cover the full duration, so
  1320. when dealing with use cases where latency of when the subtitle event is passed
  1321. on to output is not relevant this option should not be utilized.
  1322. Requires @option{-fix_sub_duration} to be set for the relevant input subtitle
  1323. stream for this to have any effect, as well as for the input subtitle stream
  1324. having to be directly mapped to the same output in which the heartbeat stream
  1325. resides.
  1326. @end table
  1327. @section Audio Options
  1328. @table @option
  1329. @item -aframes @var{number} (@emph{output})
  1330. Set the number of audio frames to output. This is an obsolete alias for
  1331. @code{-frames:a}, which you should use instead.
  1332. @item -ar[:@var{stream_specifier}] @var{freq} (@emph{input/output,per-stream})
  1333. Set the audio sampling frequency. For output streams it is set by
  1334. default to the frequency of the corresponding input stream. For input
  1335. streams this option only makes sense for audio grabbing devices and raw
  1336. demuxers and is mapped to the corresponding demuxer options.
  1337. @item -aq @var{q} (@emph{output})
  1338. Set the audio quality (codec-specific, VBR). This is an alias for -q:a.
  1339. @item -ac[:@var{stream_specifier}] @var{channels} (@emph{input/output,per-stream})
  1340. Set the number of audio channels. For output streams it is set by
  1341. default to the number of input audio channels. For input streams
  1342. this option only makes sense for audio grabbing devices and raw demuxers
  1343. and is mapped to the corresponding demuxer options.
  1344. @item -an (@emph{input/output})
  1345. As an input option, blocks all audio streams of a file from being filtered or
  1346. being automatically selected or mapped for any output. See @code{-discard}
  1347. option to disable streams individually.
  1348. As an output option, disables audio recording i.e. automatic selection or
  1349. mapping of any audio stream. For full manual control see the @code{-map}
  1350. option.
  1351. @item -acodec @var{codec} (@emph{input/output})
  1352. Set the audio codec. This is an alias for @code{-codec:a}.
  1353. @item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream})
  1354. Set the audio sample format. Use @code{-sample_fmts} to get a list
  1355. of supported sample formats.
  1356. @item -af @var{filtergraph} (@emph{output})
  1357. Create the filtergraph specified by @var{filtergraph} and use it to
  1358. filter the stream.
  1359. This is an alias for @code{-filter:a}, see the @ref{filter_option,,-filter option}.
  1360. @end table
  1361. @section Advanced Audio options
  1362. @table @option
  1363. @item -atag @var{fourcc/tag} (@emph{output})
  1364. Force audio tag/fourcc. This is an alias for @code{-tag:a}.
  1365. @item -ch_layout[:@var{stream_specifier}] @var{layout} (@emph{input/output,per-stream})
  1366. Alias for @code{-channel_layout}.
  1367. @item -channel_layout[:@var{stream_specifier}] @var{layout} (@emph{input/output,per-stream})
  1368. Set the audio channel layout. For output streams it is set by default to the
  1369. input channel layout. For input streams it overrides the channel layout of the
  1370. input. Not all decoders respect the overridden channel layout. This option
  1371. also sets the channel layout for audio grabbing devices and raw demuxers
  1372. and is mapped to the corresponding demuxer option.
  1373. @item -guess_layout_max @var{channels} (@emph{input,per-stream})
  1374. If some input channel layout is not known, try to guess only if it
  1375. corresponds to at most the specified number of channels. For example, 2
  1376. tells to @command{ffmpeg} to recognize 1 channel as mono and 2 channels as
  1377. stereo but not 6 channels as 5.1. The default is to always try to guess. Use
  1378. 0 to disable all guessing. Using the @code{-channel_layout} option to
  1379. explicitly specify an input layout also disables guessing.
  1380. @end table
  1381. @section Subtitle options
  1382. @table @option
  1383. @item -scodec @var{codec} (@emph{input/output})
  1384. Set the subtitle codec. This is an alias for @code{-codec:s}.
  1385. @item -sn (@emph{input/output})
  1386. As an input option, blocks all subtitle streams of a file from being filtered or
  1387. being automatically selected or mapped for any output. See @code{-discard}
  1388. option to disable streams individually.
  1389. As an output option, disables subtitle recording i.e. automatic selection or
  1390. mapping of any subtitle stream. For full manual control see the @code{-map}
  1391. option.
  1392. @end table
  1393. @section Advanced Subtitle options
  1394. @table @option
  1395. @item -fix_sub_duration
  1396. Fix subtitles durations. For each subtitle, wait for the next packet in the
  1397. same stream and adjust the duration of the first to avoid overlap. This is
  1398. necessary with some subtitles codecs, especially DVB subtitles, because the
  1399. duration in the original packet is only a rough estimate and the end is
  1400. actually marked by an empty subtitle frame. Failing to use this option when
  1401. necessary can result in exaggerated durations or muxing failures due to
  1402. non-monotonic timestamps.
  1403. Note that this option will delay the output of all data until the next
  1404. subtitle packet is decoded: it may increase memory consumption and latency a
  1405. lot.
  1406. @item -canvas_size @var{size}
  1407. Set the size of the canvas used to render subtitles.
  1408. @end table
  1409. @section Advanced options
  1410. @table @option
  1411. @item -map [-]@var{input_file_id}[:@var{stream_specifier}][?] | @var{[linklabel]} (@emph{output})
  1412. Create one or more streams in the output file. This option has two forms for
  1413. specifying the data source(s): the first selects one or more streams from some
  1414. input file (specified with @code{-i}), the second takes an output from some
  1415. complex filtergraph (specified with @code{-filter_complex}).
  1416. In the first form, an output stream is created for every stream from the input
  1417. file with the index @var{input_file_id}. If @var{stream_specifier} is given,
  1418. only those streams that match the specifier are used (see the
  1419. @ref{Stream specifiers} section for the @var{stream_specifier} syntax).
  1420. A @code{-} character before the stream identifier creates a "negative" mapping.
  1421. It disables matching streams from already created mappings.
  1422. A trailing @code{?} after the stream index will allow the map to be
  1423. optional: if the map matches no streams the map will be ignored instead
  1424. of failing. Note the map will still fail if an invalid input file index
  1425. is used; such as if the map refers to a non-existent input.
  1426. An alternative @var{[linklabel]} form will map outputs from complex filter
  1427. graphs (see the @option{-filter_complex} option) to the output file.
  1428. @var{linklabel} must correspond to a defined output link label in the graph.
  1429. This option may be specified multiple times, each adding more streams to the
  1430. output file. Any given input stream may also be mapped any number of times as a
  1431. source for different output streams, e.g. in order to use different encoding
  1432. options and/or filters. The streams are created in the output in the same order
  1433. in which the @code{-map} options are given on the commandline.
  1434. Using this option disables the default mappings for this output file.
  1435. Examples:
  1436. @table @emph
  1437. @item map everything
  1438. To map ALL streams from the first input file to output
  1439. @example
  1440. ffmpeg -i INPUT -map 0 output
  1441. @end example
  1442. @item select specific stream
  1443. If you have two audio streams in the first input file, these streams are
  1444. identified by @var{0:0} and @var{0:1}. You can use @code{-map} to select which
  1445. streams to place in an output file. For example:
  1446. @example
  1447. ffmpeg -i INPUT -map 0:1 out.wav
  1448. @end example
  1449. will map the second input stream in @file{INPUT} to the (single) output stream
  1450. in @file{out.wav}.
  1451. @item create multiple streams
  1452. To select the stream with index 2 from input file @file{a.mov} (specified by the
  1453. identifier @var{0:2}), and stream with index 6 from input @file{b.mov}
  1454. (specified by the identifier @var{1:6}), and copy them to the output file
  1455. @file{out.mov}:
  1456. @example
  1457. ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
  1458. @end example
  1459. @item create multiple streams 2
  1460. To select all video and the third audio stream from an input file:
  1461. @example
  1462. ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT
  1463. @end example
  1464. @item negative map
  1465. To map all the streams except the second audio, use negative mappings
  1466. @example
  1467. ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT
  1468. @end example
  1469. @item optional map
  1470. To map the video and audio streams from the first input, and using the
  1471. trailing @code{?}, ignore the audio mapping if no audio streams exist in
  1472. the first input:
  1473. @example
  1474. ffmpeg -i INPUT -map 0:v -map 0:a? OUTPUT
  1475. @end example
  1476. @item map by language
  1477. To pick the English audio stream:
  1478. @example
  1479. ffmpeg -i INPUT -map 0:m:language:eng OUTPUT
  1480. @end example
  1481. @end table
  1482. @item -ignore_unknown
  1483. Ignore input streams with unknown type instead of failing if copying
  1484. such streams is attempted.
  1485. @item -copy_unknown
  1486. Allow input streams with unknown type to be copied instead of failing if copying
  1487. such streams is attempted.
  1488. @item -map_metadata[:@var{metadata_spec_out}] @var{infile}[:@var{metadata_spec_in}] (@emph{output,per-metadata})
  1489. Set metadata information of the next output file from @var{infile}. Note that
  1490. those are file indices (zero-based), not filenames.
  1491. Optional @var{metadata_spec_in/out} parameters specify, which metadata to copy.
  1492. A metadata specifier can have the following forms:
  1493. @table @option
  1494. @item @var{g}
  1495. global metadata, i.e. metadata that applies to the whole file
  1496. @item @var{s}[:@var{stream_spec}]
  1497. per-stream metadata. @var{stream_spec} is a stream specifier as described
  1498. in the @ref{Stream specifiers} chapter. In an input metadata specifier, the first
  1499. matching stream is copied from. In an output metadata specifier, all matching
  1500. streams are copied to.
  1501. @item @var{c}:@var{chapter_index}
  1502. per-chapter metadata. @var{chapter_index} is the zero-based chapter index.
  1503. @item @var{p}:@var{program_index}
  1504. per-program metadata. @var{program_index} is the zero-based program index.
  1505. @end table
  1506. If metadata specifier is omitted, it defaults to global.
  1507. By default, global metadata is copied from the first input file,
  1508. per-stream and per-chapter metadata is copied along with streams/chapters. These
  1509. default mappings are disabled by creating any mapping of the relevant type. A negative
  1510. file index can be used to create a dummy mapping that just disables automatic copying.
  1511. For example to copy metadata from the first stream of the input file to global metadata
  1512. of the output file:
  1513. @example
  1514. ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3
  1515. @end example
  1516. To do the reverse, i.e. copy global metadata to all audio streams:
  1517. @example
  1518. ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv
  1519. @end example
  1520. Note that simple @code{0} would work as well in this example, since global
  1521. metadata is assumed by default.
  1522. @item -map_chapters @var{input_file_index} (@emph{output})
  1523. Copy chapters from input file with index @var{input_file_index} to the next
  1524. output file. If no chapter mapping is specified, then chapters are copied from
  1525. the first input file with at least one chapter. Use a negative file index to
  1526. disable any chapter copying.
  1527. @item -benchmark (@emph{global})
  1528. Show benchmarking information at the end of an encode.
  1529. Shows real, system and user time used and maximum memory consumption.
  1530. Maximum memory consumption is not supported on all systems,
  1531. it will usually display as 0 if not supported.
  1532. @item -benchmark_all (@emph{global})
  1533. Show benchmarking information during the encode.
  1534. Shows real, system and user time used in various steps (audio/video encode/decode).
  1535. @item -timelimit @var{duration} (@emph{global})
  1536. Exit after ffmpeg has been running for @var{duration} seconds in CPU user time.
  1537. @item -dump (@emph{global})
  1538. Dump each input packet to stderr.
  1539. @item -hex (@emph{global})
  1540. When dumping packets, also dump the payload.
  1541. @item -readrate @var{speed} (@emph{input})
  1542. Limit input read speed.
  1543. Its value is a floating-point positive number which represents the maximum duration of
  1544. media, in seconds, that should be ingested in one second of wallclock time.
  1545. Default value is zero and represents no imposed limitation on speed of ingestion.
  1546. Value @code{1} represents real-time speed and is equivalent to @code{-re}.
  1547. Mainly used to simulate a capture device or live input stream (e.g. when reading from a file).
  1548. Should not be used with a low value when input is an actual capture device or live stream as
  1549. it may cause packet loss.
  1550. It is useful for when flow speed of output packets is important, such as live streaming.
  1551. @item -re (@emph{input})
  1552. Read input at native frame rate. This is equivalent to setting @code{-readrate 1}.
  1553. @item -readrate_initial_burst @var{seconds}
  1554. Set an initial read burst time, in seconds, after which @option{-re/-readrate}
  1555. will be enforced.
  1556. @item -vsync @var{parameter} (@emph{global})
  1557. @itemx -fps_mode[:@var{stream_specifier}] @var{parameter} (@emph{output,per-stream})
  1558. Set video sync method / framerate mode. vsync is applied to all output video streams
  1559. but can be overridden for a stream by setting fps_mode. vsync is deprecated and will be
  1560. removed in the future.
  1561. For compatibility reasons some of the values for vsync can be specified as numbers (shown
  1562. in parentheses in the following table).
  1563. @table @option
  1564. @item passthrough (0)
  1565. Each frame is passed with its timestamp from the demuxer to the muxer.
  1566. @item cfr (1)
  1567. Frames will be duplicated and dropped to achieve exactly the requested
  1568. constant frame rate.
  1569. @item vfr (2)
  1570. Frames are passed through with their timestamp or dropped so as to
  1571. prevent 2 frames from having the same timestamp.
  1572. @item auto (-1)
  1573. Chooses between cfr and vfr depending on muxer capabilities. This is the
  1574. default method.
  1575. @end table
  1576. Note that the timestamps may be further modified by the muxer, after this.
  1577. For example, in the case that the format option @option{avoid_negative_ts}
  1578. is enabled.
  1579. With -map you can select from which stream the timestamps should be
  1580. taken. You can leave either video or audio unchanged and sync the
  1581. remaining stream(s) to the unchanged one.
  1582. @item -frame_drop_threshold @var{parameter}
  1583. Frame drop threshold, which specifies how much behind video frames can
  1584. be before they are dropped. In frame rate units, so 1.0 is one frame.
  1585. The default is -1.1. One possible usecase is to avoid framedrops in case
  1586. of noisy timestamps or to increase frame drop precision in case of exact
  1587. timestamps.
  1588. @item -apad @var{parameters} (@emph{output,per-stream})
  1589. Pad the output audio stream(s). This is the same as applying @code{-af apad}.
  1590. Argument is a string of filter parameters composed the same as with the @code{apad} filter.
  1591. @code{-shortest} must be set for this output for the option to take effect.
  1592. @item -copyts
  1593. Do not process input timestamps, but keep their values without trying
  1594. to sanitize them. In particular, do not remove the initial start time
  1595. offset value.
  1596. Note that, depending on the @option{vsync} option or on specific muxer
  1597. processing (e.g. in case the format option @option{avoid_negative_ts}
  1598. is enabled) the output timestamps may mismatch with the input
  1599. timestamps even when this option is selected.
  1600. @item -start_at_zero
  1601. When used with @option{copyts}, shift input timestamps so they start at zero.
  1602. This means that using e.g. @code{-ss 50} will make output timestamps start at
  1603. 50 seconds, regardless of what timestamp the input file started at.
  1604. @item -copytb @var{mode}
  1605. Specify how to set the encoder timebase when stream copying. @var{mode} is an
  1606. integer numeric value, and can assume one of the following values:
  1607. @table @option
  1608. @item 1
  1609. Use the demuxer timebase.
  1610. The time base is copied to the output encoder from the corresponding input
  1611. demuxer. This is sometimes required to avoid non monotonically increasing
  1612. timestamps when copying video streams with variable frame rate.
  1613. @item 0
  1614. Use the decoder timebase.
  1615. The time base is copied to the output encoder from the corresponding input
  1616. decoder.
  1617. @item -1
  1618. Try to make the choice automatically, in order to generate a sane output.
  1619. @end table
  1620. Default value is -1.
  1621. @item -enc_time_base[:@var{stream_specifier}] @var{timebase} (@emph{output,per-stream})
  1622. Set the encoder timebase. @var{timebase} can assume one of the following values:
  1623. @table @option
  1624. @item 0
  1625. Assign a default value according to the media type.
  1626. For video - use 1/framerate, for audio - use 1/samplerate.
  1627. @item demux
  1628. Use the timebase from the demuxer.
  1629. @item filter
  1630. Use the timebase from the filtergraph.
  1631. @item a positive number
  1632. Use the provided number as the timebase.
  1633. This field can be provided as a ratio of two integers (e.g. 1:24, 1:48000)
  1634. or as a decimal number (e.g. 0.04166, 2.0833e-5)
  1635. @end table
  1636. Default value is 0.
  1637. @item -bitexact (@emph{input/output})
  1638. Enable bitexact mode for (de)muxer and (de/en)coder
  1639. @item -shortest (@emph{output})
  1640. Finish encoding when the shortest output stream ends.
  1641. Note that this option may require buffering frames, which introduces extra
  1642. latency. The maximum amount of this latency may be controlled with the
  1643. @code{-shortest_buf_duration} option.
  1644. @item -shortest_buf_duration @var{duration} (@emph{output})
  1645. The @code{-shortest} option may require buffering potentially large amounts
  1646. of data when at least one of the streams is "sparse" (i.e. has large gaps
  1647. between frames – this is typically the case for subtitles).
  1648. This option controls the maximum duration of buffered frames in seconds.
  1649. Larger values may allow the @code{-shortest} option to produce more accurate
  1650. results, but increase memory use and latency.
  1651. The default value is 10 seconds.
  1652. @item -dts_delta_threshold @var{threshold}
  1653. Timestamp discontinuity delta threshold, expressed as a decimal number
  1654. of seconds.
  1655. The timestamp discontinuity correction enabled by this option is only
  1656. applied to input formats accepting timestamp discontinuity (for which
  1657. the @code{AVFMT_TS_DISCONT} flag is enabled), e.g. MPEG-TS and HLS, and
  1658. is automatically disabled when employing the @code{-copyts} option
  1659. (unless wrapping is detected).
  1660. If a timestamp discontinuity is detected whose absolute value is
  1661. greater than @var{threshold}, ffmpeg will remove the discontinuity by
  1662. decreasing/increasing the current DTS and PTS by the corresponding
  1663. delta value.
  1664. The default value is 10.
  1665. @item -dts_error_threshold @var{threshold}
  1666. Timestamp error delta threshold, expressed as a decimal number of
  1667. seconds.
  1668. The timestamp correction enabled by this option is only applied to
  1669. input formats not accepting timestamp discontinuity (for which the
  1670. @code{AVFMT_TS_DISCONT} flag is not enabled).
  1671. If a timestamp discontinuity is detected whose absolute value is
  1672. greater than @var{threshold}, ffmpeg will drop the PTS/DTS timestamp
  1673. value.
  1674. The default value is @code{3600*30} (30 hours), which is arbitrarily
  1675. picked and quite conservative.
  1676. @item -muxdelay @var{seconds} (@emph{output})
  1677. Set the maximum demux-decode delay.
  1678. @item -muxpreload @var{seconds} (@emph{output})
  1679. Set the initial demux-decode delay.
  1680. @item -streamid @var{output-stream-index}:@var{new-value} (@emph{output})
  1681. Assign a new stream-id value to an output stream. This option should be
  1682. specified prior to the output filename to which it applies.
  1683. For the situation where multiple output files exist, a streamid
  1684. may be reassigned to a different value.
  1685. For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for
  1686. an output mpegts file:
  1687. @example
  1688. ffmpeg -i inurl -streamid 0:33 -streamid 1:36 out.ts
  1689. @end example
  1690. @item -bsf[:@var{stream_specifier}] @var{bitstream_filters} (@emph{input/output,per-stream})
  1691. Apply bitstream filters to matching streams. The filters are applied to each
  1692. packet as it is received from the demuxer (when used as an input option) or
  1693. before it is sent to the muxer (when used as an output option).
  1694. @var{bitstream_filters} is a comma-separated list of bitstream filter
  1695. specifications, each of the form
  1696. @example
  1697. @var{filter}[=@var{optname0}=@var{optval0}:@var{optname1}=@var{optval1}:...]
  1698. @end example
  1699. Any of the ',=:' characters that are to be a part of an option value need to be
  1700. escaped with a backslash.
  1701. Use the @code{-bsfs} option to get the list of bitstream filters.
  1702. E.g.
  1703. @example
  1704. ffmpeg -bsf:v h264_mp4toannexb -i h264.mp4 -c:v copy -an out.h264
  1705. @end example
  1706. applies the @code{h264_mp4toannexb} bitstream filter (which converts
  1707. MP4-encapsulated H.264 stream to Annex B) to the @emph{input} video stream.
  1708. On the other hand,
  1709. @example
  1710. ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt
  1711. @end example
  1712. applies the @code{mov2textsub} bitstream filter (which extracts text from MOV
  1713. subtitles) to the @emph{output} subtitle stream. Note, however, that since both
  1714. examples use @code{-c copy}, it matters little whether the filters are applied
  1715. on input or output - that would change if transcoding was happening.
  1716. @item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{input/output,per-stream})
  1717. Force a tag/fourcc for matching streams.
  1718. @item -timecode @var{hh}:@var{mm}:@var{ss}SEP@var{ff}
  1719. Specify Timecode for writing. @var{SEP} is ':' for non drop timecode and ';'
  1720. (or '.') for drop.
  1721. @example
  1722. ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg
  1723. @end example
  1724. @anchor{filter_complex_option}
  1725. @item -filter_complex @var{filtergraph} (@emph{global})
  1726. Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
  1727. outputs. For simple graphs -- those with one input and one output of the same
  1728. type -- see the @option{-filter} options. @var{filtergraph} is a description of
  1729. the filtergraph, as described in the ``Filtergraph syntax'' section of the
  1730. ffmpeg-filters manual. This option may be specified multiple times - each use
  1731. creates a new complex filtergraph.
  1732. Inputs to a complex filtergraph may come from different source types,
  1733. distinguished by the format of the corresponding link label:
  1734. @itemize
  1735. @item
  1736. To connect an input stream, use @code{[file_index:stream_specifier]} (i.e. the
  1737. same syntax as @option{-map}). If @var{stream_specifier} matches multiple
  1738. streams, the first one will be used.
  1739. @item
  1740. To connect a loopback decoder use [dec:@var{dec_idx}], where @var{dec_idx} is
  1741. the index of the loopback decoder to be connected to given input.
  1742. @item
  1743. To connect an output from another complex filtergraph, use its link label. E.g
  1744. the following example:
  1745. @example
  1746. ffmpeg -i input.mkv \
  1747. -filter_complex '[0:v]scale=size=hd1080,split=outputs=2[for_enc][orig_scaled]' \
  1748. -c:v libx264 -map '[for_enc]' output.mkv \
  1749. -dec 0:0 \
  1750. -filter_complex '[dec:0][orig_scaled]hstack[stacked]' \
  1751. -map '[stacked]' -c:v ffv1 comparison.mkv
  1752. @end example
  1753. reads an input video and
  1754. @itemize
  1755. @item
  1756. (line 2) uses a complex filtergraph with one input and two outputs
  1757. to scale the video to 1920x1080 and duplicate the result to both
  1758. outputs;
  1759. @item
  1760. (line 3) encodes one scaled output with @code{libx264} and writes the result to
  1761. @file{output.mkv};
  1762. @item
  1763. (line 4) decodes this encoded stream with a loopback decoder;
  1764. @item
  1765. (line 5) places the output of the loopback decoder (i.e. the
  1766. @code{libx264}-encoded video) side by side with the scaled original input;
  1767. @item
  1768. (line 6) combined video is then losslessly encoded and written into
  1769. @file{comparison.mkv}.
  1770. @end itemize
  1771. Note that the two filtergraphs cannot be combined into one, because then there
  1772. would be a cycle in the transcoding pipeline (filtergraph output goes to
  1773. encoding, from there to decoding, then back to the same graph), and such cycles
  1774. are not allowed.
  1775. @end itemize
  1776. An unlabeled input will be connected to the first unused input stream of the
  1777. matching type.
  1778. Output link labels are referred to with @option{-map}. Unlabeled outputs are
  1779. added to the first output file.
  1780. Note that with this option it is possible to use only lavfi sources without
  1781. normal input files.
  1782. For example, to overlay an image over video
  1783. @example
  1784. ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
  1785. '[out]' out.mkv
  1786. @end example
  1787. Here @code{[0:v]} refers to the first video stream in the first input file,
  1788. which is linked to the first (main) input of the overlay filter. Similarly the
  1789. first video stream in the second input is linked to the second (overlay) input
  1790. of overlay.
  1791. Assuming there is only one video stream in each input file, we can omit input
  1792. labels, so the above is equivalent to
  1793. @example
  1794. ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map
  1795. '[out]' out.mkv
  1796. @end example
  1797. Furthermore we can omit the output label and the single output from the filter
  1798. graph will be added to the output file automatically, so we can simply write
  1799. @example
  1800. ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv
  1801. @end example
  1802. As a special exception, you can use a bitmap subtitle stream as input: it
  1803. will be converted into a video with the same size as the largest video in
  1804. the file, or 720x576 if no video is present. Note that this is an
  1805. experimental and temporary solution. It will be removed once libavfilter has
  1806. proper support for subtitles.
  1807. For example, to hardcode subtitles on top of a DVB-T recording stored in
  1808. MPEG-TS format, delaying the subtitles by 1 second:
  1809. @example
  1810. ffmpeg -i input.ts -filter_complex \
  1811. '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
  1812. -sn -map '#0x2dc' output.mkv
  1813. @end example
  1814. (0x2d0, 0x2dc and 0x2ef are the MPEG-TS PIDs of respectively the video,
  1815. audio and subtitles streams; 0:0, 0:3 and 0:7 would have worked too)
  1816. To generate 5 seconds of pure red video using lavfi @code{color} source:
  1817. @example
  1818. ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv
  1819. @end example
  1820. @item -filter_complex_threads @var{nb_threads} (@emph{global})
  1821. Defines how many threads are used to process a filter_complex graph.
  1822. Similar to filter_threads but used for @code{-filter_complex} graphs only.
  1823. The default is the number of available CPUs.
  1824. @item -lavfi @var{filtergraph} (@emph{global})
  1825. Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
  1826. outputs. Equivalent to @option{-filter_complex}.
  1827. @item -accurate_seek (@emph{input})
  1828. This option enables or disables accurate seeking in input files with the
  1829. @option{-ss} option. It is enabled by default, so seeking is accurate when
  1830. transcoding. Use @option{-noaccurate_seek} to disable it, which may be useful
  1831. e.g. when copying some streams and transcoding the others.
  1832. @item -seek_timestamp (@emph{input})
  1833. This option enables or disables seeking by timestamp in input files with the
  1834. @option{-ss} option. It is disabled by default. If enabled, the argument
  1835. to the @option{-ss} option is considered an actual timestamp, and is not
  1836. offset by the start time of the file. This matters only for files which do
  1837. not start from timestamp 0, such as transport streams.
  1838. @item -thread_queue_size @var{size} (@emph{input/output})
  1839. For input, this option sets the maximum number of queued packets when reading
  1840. from the file or device. With low latency / high rate live streams, packets may
  1841. be discarded if they are not read in a timely manner; setting this value can
  1842. force ffmpeg to use a separate input thread and read packets as soon as they
  1843. arrive. By default ffmpeg only does this if multiple inputs are specified.
  1844. For output, this option specified the maximum number of packets that may be
  1845. queued to each muxing thread.
  1846. @item -sdp_file @var{file} (@emph{global})
  1847. Print sdp information for an output stream to @var{file}.
  1848. This allows dumping sdp information when at least one output isn't an
  1849. rtp stream. (Requires at least one of the output formats to be rtp).
  1850. @item -discard (@emph{input})
  1851. Allows discarding specific streams or frames from streams.
  1852. Any input stream can be fully discarded, using value @code{all} whereas
  1853. selective discarding of frames from a stream occurs at the demuxer
  1854. and is not supported by all demuxers.
  1855. @table @option
  1856. @item none
  1857. Discard no frame.
  1858. @item default
  1859. Default, which discards no frames.
  1860. @item noref
  1861. Discard all non-reference frames.
  1862. @item bidir
  1863. Discard all bidirectional frames.
  1864. @item nokey
  1865. Discard all frames excepts keyframes.
  1866. @item all
  1867. Discard all frames.
  1868. @end table
  1869. @item -abort_on @var{flags} (@emph{global})
  1870. Stop and abort on various conditions. The following flags are available:
  1871. @table @option
  1872. @item empty_output
  1873. No packets were passed to the muxer, the output is empty.
  1874. @item empty_output_stream
  1875. No packets were passed to the muxer in some of the output streams.
  1876. @end table
  1877. @item -max_error_rate (@emph{global})
  1878. Set fraction of decoding frame failures across all inputs which when crossed
  1879. ffmpeg will return exit code 69. Crossing this threshold does not terminate
  1880. processing. Range is a floating-point number between 0 to 1. Default is 2/3.
  1881. @item -xerror (@emph{global})
  1882. Stop and exit on error
  1883. @item -max_muxing_queue_size @var{packets} (@emph{output,per-stream})
  1884. When transcoding audio and/or video streams, ffmpeg will not begin writing into
  1885. the output until it has one packet for each such stream. While waiting for that
  1886. to happen, packets for other streams are buffered. This option sets the size of
  1887. this buffer, in packets, for the matching output stream.
  1888. The default value of this option should be high enough for most uses, so only
  1889. touch this option if you are sure that you need it.
  1890. @item -muxing_queue_data_threshold @var{bytes} (@emph{output,per-stream})
  1891. This is a minimum threshold until which the muxing queue size is not taken into
  1892. account. Defaults to 50 megabytes per stream, and is based on the overall size
  1893. of packets passed to the muxer.
  1894. @item -auto_conversion_filters (@emph{global})
  1895. Enable automatically inserting format conversion filters in all filter
  1896. graphs, including those defined by @option{-vf}, @option{-af},
  1897. @option{-filter_complex} and @option{-lavfi}. If filter format negotiation
  1898. requires a conversion, the initialization of the filters will fail.
  1899. Conversions can still be performed by inserting the relevant conversion
  1900. filter (scale, aresample) in the graph.
  1901. On by default, to explicitly disable it you need to specify
  1902. @code{-noauto_conversion_filters}.
  1903. @item -bits_per_raw_sample[:@var{stream_specifier}] @var{value} (@emph{output,per-stream})
  1904. Declare the number of bits per raw sample in the given output stream to be
  1905. @var{value}. Note that this option sets the information provided to the
  1906. encoder/muxer, it does not change the stream to conform to this value. Setting
  1907. values that do not match the stream properties may result in encoding failures
  1908. or invalid output files.
  1909. @anchor{stats_enc_options}
  1910. @item -stats_enc_pre[:@var{stream_specifier}] @var{path} (@emph{output,per-stream})
  1911. @item -stats_enc_post[:@var{stream_specifier}] @var{path} (@emph{output,per-stream})
  1912. @item -stats_mux_pre[:@var{stream_specifier}] @var{path} (@emph{output,per-stream})
  1913. Write per-frame encoding information about the matching streams into the file
  1914. given by @var{path}.
  1915. @option{-stats_enc_pre} writes information about raw video or audio frames right
  1916. before they are sent for encoding, while @option{-stats_enc_post} writes
  1917. information about encoded packets as they are received from the encoder.
  1918. @option{-stats_mux_pre} writes information about packets just as they are about to
  1919. be sent to the muxer. Every frame or packet produces one line in the specified
  1920. file. The format of this line is controlled by @option{-stats_enc_pre_fmt} /
  1921. @option{-stats_enc_post_fmt} / @option{-stats_mux_pre_fmt}.
  1922. When stats for multiple streams are written into a single file, the lines
  1923. corresponding to different streams will be interleaved. The precise order of
  1924. this interleaving is not specified and not guaranteed to remain stable between
  1925. different invocations of the program, even with the same options.
  1926. @item -stats_enc_pre_fmt[:@var{stream_specifier}] @var{format_spec} (@emph{output,per-stream})
  1927. @item -stats_enc_post_fmt[:@var{stream_specifier}] @var{format_spec} (@emph{output,per-stream})
  1928. @item -stats_mux_pre_fmt[:@var{stream_specifier}] @var{format_spec} (@emph{output,per-stream})
  1929. Specify the format for the lines written with @option{-stats_enc_pre} /
  1930. @option{-stats_enc_post} / @option{-stats_mux_pre}.
  1931. @var{format_spec} is a string that may contain directives of the form
  1932. @var{@{fmt@}}. @var{format_spec} is backslash-escaped --- use \@{, \@}, and \\
  1933. to write a literal @{, @}, or \, respectively, into the output.
  1934. The directives given with @var{fmt} may be one of the following:
  1935. @table @option
  1936. @item fidx
  1937. Index of the output file.
  1938. @item sidx
  1939. Index of the output stream in the file.
  1940. @item n
  1941. Frame number. Pre-encoding: number of frames sent to the encoder so far.
  1942. Post-encoding: number of packets received from the encoder so far.
  1943. Muxing: number of packets submitted to the muxer for this stream so far.
  1944. @item ni
  1945. Input frame number. Index of the input frame (i.e. output by a decoder) that
  1946. corresponds to this output frame or packet. -1 if unavailable.
  1947. @item tb
  1948. Timebase in which this frame/packet's timestamps are expressed, as a rational
  1949. number @var{num/den}. Note that encoder and muxer may use different timebases.
  1950. @item tbi
  1951. Timebase for @var{ptsi}, as a rational number @var{num/den}. Available when
  1952. @var{ptsi} is available, @var{0/1} otherwise.
  1953. @item pts
  1954. Presentation timestamp of the frame or packet, as an integer. Should be
  1955. multiplied by the timebase to compute presentation time.
  1956. @item ptsi
  1957. Presentation timestamp of the input frame (see @var{ni}), as an integer. Should
  1958. be multiplied by @var{tbi} to compute presentation time. Printed as
  1959. (2^63 - 1 = 9223372036854775807) when not available.
  1960. @item t
  1961. Presentation time of the frame or packet, as a decimal number. Equal to
  1962. @var{pts} multiplied by @var{tb}.
  1963. @item ti
  1964. Presentation time of the input frame (see @var{ni}), as a decimal number. Equal
  1965. to @var{ptsi} multiplied by @var{tbi}. Printed as inf when not available.
  1966. @item dts (@emph{packet})
  1967. Decoding timestamp of the packet, as an integer. Should be multiplied by the
  1968. timebase to compute presentation time.
  1969. @item dt (@emph{packet})
  1970. Decoding time of the frame or packet, as a decimal number. Equal to
  1971. @var{dts} multiplied by @var{tb}.
  1972. @item sn (@emph{frame,audio})
  1973. Number of audio samples sent to the encoder so far.
  1974. @item samp (@emph{frame,audio})
  1975. Number of audio samples in the frame.
  1976. @item size (@emph{packet})
  1977. Size of the encoded packet in bytes.
  1978. @item br (@emph{packet})
  1979. Current bitrate in bits per second.
  1980. @item abr (@emph{packet})
  1981. Average bitrate for the whole stream so far, in bits per second, -1 if it cannot
  1982. be determined at this point.
  1983. @item key (@emph{packet})
  1984. Character 'K' if the packet contains a keyframe, character 'N' otherwise.
  1985. @end table
  1986. Directives tagged with @emph{packet} may only be used with
  1987. @option{-stats_enc_post_fmt} and @option{-stats_mux_pre_fmt}.
  1988. Directives tagged with @emph{frame} may only be used with
  1989. @option{-stats_enc_pre_fmt}.
  1990. Directives tagged with @emph{audio} may only be used with audio streams.
  1991. The default format strings are:
  1992. @table @option
  1993. @item pre-encoding
  1994. @{fidx@} @{sidx@} @{n@} @{t@}
  1995. @item post-encoding
  1996. @{fidx@} @{sidx@} @{n@} @{t@}
  1997. @end table
  1998. In the future, new items may be added to the end of the default formatting
  1999. strings. Users who depend on the format staying exactly the same, should
  2000. prescribe it manually.
  2001. Note that stats for different streams written into the same file may have
  2002. different formats.
  2003. @end table
  2004. @section Preset files
  2005. A preset file contains a sequence of @var{option}=@var{value} pairs,
  2006. one for each line, specifying a sequence of options which would be
  2007. awkward to specify on the command line. Lines starting with the hash
  2008. ('#') character are ignored and are used to provide comments. Check
  2009. the @file{presets} directory in the FFmpeg source tree for examples.
  2010. There are two types of preset files: ffpreset and avpreset files.
  2011. @subsection ffpreset files
  2012. ffpreset files are specified with the @code{vpre}, @code{apre},
  2013. @code{spre}, and @code{fpre} options. The @code{fpre} option takes the
  2014. filename of the preset instead of a preset name as input and can be
  2015. used for any kind of codec. For the @code{vpre}, @code{apre}, and
  2016. @code{spre} options, the options specified in a preset file are
  2017. applied to the currently selected codec of the same type as the preset
  2018. option.
  2019. The argument passed to the @code{vpre}, @code{apre}, and @code{spre}
  2020. preset options identifies the preset file to use according to the
  2021. following rules:
  2022. First ffmpeg searches for a file named @var{arg}.ffpreset in the
  2023. directories @file{$FFMPEG_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
  2024. the datadir defined at configuration time (usually @file{PREFIX/share/ffmpeg})
  2025. or in a @file{ffpresets} folder along the executable on win32,
  2026. in that order. For example, if the argument is @code{libvpx-1080p}, it will
  2027. search for the file @file{libvpx-1080p.ffpreset}.
  2028. If no such file is found, then ffmpeg will search for a file named
  2029. @var{codec_name}-@var{arg}.ffpreset in the above-mentioned
  2030. directories, where @var{codec_name} is the name of the codec to which
  2031. the preset file options will be applied. For example, if you select
  2032. the video codec with @code{-vcodec libvpx} and use @code{-vpre 1080p},
  2033. then it will search for the file @file{libvpx-1080p.ffpreset}.
  2034. @subsection avpreset files
  2035. avpreset files are specified with the @code{pre} option. They work similar to
  2036. ffpreset files, but they only allow encoder- specific options. Therefore, an
  2037. @var{option}=@var{value} pair specifying an encoder cannot be used.
  2038. When the @code{pre} option is specified, ffmpeg will look for files with the
  2039. suffix .avpreset in the directories @file{$AVCONV_DATADIR} (if set), and
  2040. @file{$HOME/.avconv}, and in the datadir defined at configuration time (usually
  2041. @file{PREFIX/share/ffmpeg}), in that order.
  2042. First ffmpeg searches for a file named @var{codec_name}-@var{arg}.avpreset in
  2043. the above-mentioned directories, where @var{codec_name} is the name of the codec
  2044. to which the preset file options will be applied. For example, if you select the
  2045. video codec with @code{-vcodec libvpx} and use @code{-pre 1080p}, then it will
  2046. search for the file @file{libvpx-1080p.avpreset}.
  2047. If no such file is found, then ffmpeg will search for a file named
  2048. @var{arg}.avpreset in the same directories.
  2049. @anchor{vstats_file_format}
  2050. @section vstats file format
  2051. The @code{-vstats} and @code{-vstats_file} options enable generation of a file
  2052. containing statistics about the generated video outputs.
  2053. The @code{-vstats_version} option controls the format version of the generated
  2054. file.
  2055. With version @code{1} the format is:
  2056. @example
  2057. frame= @var{FRAME} q= @var{FRAME_QUALITY} PSNR= @var{PSNR} f_size= @var{FRAME_SIZE} s_size= @var{STREAM_SIZE}kB time= @var{TIMESTAMP} br= @var{BITRATE}kbits/s avg_br= @var{AVERAGE_BITRATE}kbits/s
  2058. @end example
  2059. With version @code{2} the format is:
  2060. @example
  2061. out= @var{OUT_FILE_INDEX} st= @var{OUT_FILE_STREAM_INDEX} frame= @var{FRAME_NUMBER} q= @var{FRAME_QUALITY}f PSNR= @var{PSNR} f_size= @var{FRAME_SIZE} s_size= @var{STREAM_SIZE}kB time= @var{TIMESTAMP} br= @var{BITRATE}kbits/s avg_br= @var{AVERAGE_BITRATE}kbits/s
  2062. @end example
  2063. The value corresponding to each key is described below:
  2064. @table @option
  2065. @item avg_br
  2066. average bitrate expressed in Kbits/s
  2067. @item br
  2068. bitrate expressed in Kbits/s
  2069. @item frame
  2070. number of encoded frame
  2071. @item out
  2072. out file index
  2073. @item PSNR
  2074. Peak Signal to Noise Ratio
  2075. @item q
  2076. quality of the frame
  2077. @item f_size
  2078. encoded packet size expressed as number of bytes
  2079. @item s_size
  2080. stream size expressed in KiB
  2081. @item st
  2082. out file stream index
  2083. @item time
  2084. time of the packet
  2085. @item type
  2086. picture type
  2087. @end table
  2088. See also the @ref{stats_enc_options,,-stats_enc options} for an alternative way
  2089. to show encoding statistics.
  2090. @c man end OPTIONS
  2091. @chapter Examples
  2092. @c man begin EXAMPLES
  2093. @section Video and Audio grabbing
  2094. If you specify the input format and device then ffmpeg can grab video
  2095. and audio directly.
  2096. @example
  2097. ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
  2098. @end example
  2099. Or with an ALSA audio source (mono input, card id 1) instead of OSS:
  2100. @example
  2101. ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg
  2102. @end example
  2103. Note that you must activate the right video source and channel before
  2104. launching ffmpeg with any TV viewer such as
  2105. @uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also
  2106. have to set the audio recording levels correctly with a
  2107. standard mixer.
  2108. @section X11 grabbing
  2109. Grab the X11 display with ffmpeg via
  2110. @example
  2111. ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0 /tmp/out.mpg
  2112. @end example
  2113. 0.0 is display.screen number of your X11 server, same as
  2114. the DISPLAY environment variable.
  2115. @example
  2116. ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0+10,20 /tmp/out.mpg
  2117. @end example
  2118. 0.0 is display.screen number of your X11 server, same as the DISPLAY environment
  2119. variable. 10 is the x-offset and 20 the y-offset for the grabbing.
  2120. @section Video and Audio file format conversion
  2121. Any supported file format and protocol can serve as input to ffmpeg:
  2122. Examples:
  2123. @itemize
  2124. @item
  2125. You can use YUV files as input:
  2126. @example
  2127. ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
  2128. @end example
  2129. It will use the files:
  2130. @example
  2131. /tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
  2132. /tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
  2133. @end example
  2134. The Y files use twice the resolution of the U and V files. They are
  2135. raw files, without header. They can be generated by all decent video
  2136. decoders. You must specify the size of the image with the @option{-s} option
  2137. if ffmpeg cannot guess it.
  2138. @item
  2139. You can input from a raw YUV420P file:
  2140. @example
  2141. ffmpeg -i /tmp/test.yuv /tmp/out.avi
  2142. @end example
  2143. test.yuv is a file containing raw YUV planar data. Each frame is composed
  2144. of the Y plane followed by the U and V planes at half vertical and
  2145. horizontal resolution.
  2146. @item
  2147. You can output to a raw YUV420P file:
  2148. @example
  2149. ffmpeg -i mydivx.avi hugefile.yuv
  2150. @end example
  2151. @item
  2152. You can set several input files and output files:
  2153. @example
  2154. ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
  2155. @end example
  2156. Converts the audio file a.wav and the raw YUV video file a.yuv
  2157. to MPEG file a.mpg.
  2158. @item
  2159. You can also do audio and video conversions at the same time:
  2160. @example
  2161. ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
  2162. @end example
  2163. Converts a.wav to MPEG audio at 22050 Hz sample rate.
  2164. @item
  2165. You can encode to several formats at the same time and define a
  2166. mapping from input stream to output streams:
  2167. @example
  2168. ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2
  2169. @end example
  2170. Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
  2171. file:index' specifies which input stream is used for each output
  2172. stream, in the order of the definition of output streams.
  2173. @item
  2174. You can transcode decrypted VOBs:
  2175. @example
  2176. ffmpeg -i snatch_1.vob -f avi -c:v mpeg4 -b:v 800k -g 300 -bf 2 -c:a libmp3lame -b:a 128k snatch.avi
  2177. @end example
  2178. This is a typical DVD ripping example; the input is a VOB file, the
  2179. output an AVI file with MPEG-4 video and MP3 audio. Note that in this
  2180. command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
  2181. GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
  2182. input video. Furthermore, the audio stream is MP3-encoded so you need
  2183. to enable LAME support by passing @code{--enable-libmp3lame} to configure.
  2184. The mapping is particularly useful for DVD transcoding
  2185. to get the desired audio language.
  2186. NOTE: To see the supported input formats, use @code{ffmpeg -demuxers}.
  2187. @item
  2188. You can extract images from a video, or create a video from many images:
  2189. For extracting images from a video:
  2190. @example
  2191. ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
  2192. @end example
  2193. This will extract one video frame per second from the video and will
  2194. output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg},
  2195. etc. Images will be rescaled to fit the new WxH values.
  2196. If you want to extract just a limited number of frames, you can use the
  2197. above command in combination with the @code{-frames:v} or @code{-t} option,
  2198. or in combination with -ss to start extracting from a certain point in time.
  2199. For creating a video from many images:
  2200. @example
  2201. ffmpeg -f image2 -framerate 12 -i foo-%03d.jpeg -s WxH foo.avi
  2202. @end example
  2203. The syntax @code{foo-%03d.jpeg} specifies to use a decimal number
  2204. composed of three digits padded with zeroes to express the sequence
  2205. number. It is the same syntax supported by the C printf function, but
  2206. only formats accepting a normal integer are suitable.
  2207. When importing an image sequence, -i also supports expanding
  2208. shell-like wildcard patterns (globbing) internally, by selecting the
  2209. image2-specific @code{-pattern_type glob} option.
  2210. For example, for creating a video from filenames matching the glob pattern
  2211. @code{foo-*.jpeg}:
  2212. @example
  2213. ffmpeg -f image2 -pattern_type glob -framerate 12 -i 'foo-*.jpeg' -s WxH foo.avi
  2214. @end example
  2215. @item
  2216. You can put many streams of the same type in the output:
  2217. @example
  2218. ffmpeg -i test1.avi -i test2.avi -map 1:1 -map 1:0 -map 0:1 -map 0:0 -c copy -y test12.nut
  2219. @end example
  2220. The resulting output file @file{test12.nut} will contain the first four streams
  2221. from the input files in reverse order.
  2222. @item
  2223. To force CBR video output:
  2224. @example
  2225. ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
  2226. @end example
  2227. @item
  2228. The four options lmin, lmax, mblmin and mblmax use 'lambda' units,
  2229. but you may use the QP2LAMBDA constant to easily convert from 'q' units:
  2230. @example
  2231. ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
  2232. @end example
  2233. @end itemize
  2234. @c man end EXAMPLES
  2235. @include config.texi
  2236. @ifset config-all
  2237. @ifset config-avutil
  2238. @include utils.texi
  2239. @end ifset
  2240. @ifset config-avcodec
  2241. @include codecs.texi
  2242. @include bitstream_filters.texi
  2243. @end ifset
  2244. @ifset config-avformat
  2245. @include formats.texi
  2246. @include protocols.texi
  2247. @end ifset
  2248. @ifset config-avdevice
  2249. @include devices.texi
  2250. @end ifset
  2251. @ifset config-swresample
  2252. @include resampler.texi
  2253. @end ifset
  2254. @ifset config-swscale
  2255. @include scaler.texi
  2256. @end ifset
  2257. @ifset config-avfilter
  2258. @include filters.texi
  2259. @end ifset
  2260. @include general_contents.texi
  2261. @end ifset
  2262. @chapter See Also
  2263. @ifhtml
  2264. @ifset config-all
  2265. @url{ffmpeg.html,ffmpeg}
  2266. @end ifset
  2267. @ifset config-not-all
  2268. @url{ffmpeg-all.html,ffmpeg-all},
  2269. @end ifset
  2270. @url{ffplay.html,ffplay}, @url{ffprobe.html,ffprobe},
  2271. @url{ffmpeg-utils.html,ffmpeg-utils},
  2272. @url{ffmpeg-scaler.html,ffmpeg-scaler},
  2273. @url{ffmpeg-resampler.html,ffmpeg-resampler},
  2274. @url{ffmpeg-codecs.html,ffmpeg-codecs},
  2275. @url{ffmpeg-bitstream-filters.html,ffmpeg-bitstream-filters},
  2276. @url{ffmpeg-formats.html,ffmpeg-formats},
  2277. @url{ffmpeg-devices.html,ffmpeg-devices},
  2278. @url{ffmpeg-protocols.html,ffmpeg-protocols},
  2279. @url{ffmpeg-filters.html,ffmpeg-filters}
  2280. @end ifhtml
  2281. @ifnothtml
  2282. @ifset config-all
  2283. ffmpeg(1),
  2284. @end ifset
  2285. @ifset config-not-all
  2286. ffmpeg-all(1),
  2287. @end ifset
  2288. ffplay(1), ffprobe(1),
  2289. ffmpeg-utils(1), ffmpeg-scaler(1), ffmpeg-resampler(1),
  2290. ffmpeg-codecs(1), ffmpeg-bitstream-filters(1), ffmpeg-formats(1),
  2291. ffmpeg-devices(1), ffmpeg-protocols(1), ffmpeg-filters(1)
  2292. @end ifnothtml
  2293. @include authors.texi
  2294. @ignore
  2295. @setfilename ffmpeg
  2296. @settitle ffmpeg media converter
  2297. @end ignore
  2298. @bye