ffmpeg.texi 80 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 very fast video and audio converter that can also grab from
  14. a live audio/video source. It can also convert between arbitrary sample
  15. rates and resize video on the fly with a high quality polyphase filter.
  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. @itemize
  40. @item
  41. To set the video bitrate of the output file to 64 kbit/s:
  42. @example
  43. ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi
  44. @end example
  45. @item
  46. To force the frame rate of the output file to 24 fps:
  47. @example
  48. ffmpeg -i input.avi -r 24 output.avi
  49. @end example
  50. @item
  51. To force the frame rate of the input file (valid for raw formats only)
  52. to 1 fps and the frame rate of the output file to 24 fps:
  53. @example
  54. ffmpeg -r 1 -i input.m2v -r 24 output.avi
  55. @end example
  56. @end itemize
  57. The format option may be needed for raw input files.
  58. @c man end DESCRIPTION
  59. @chapter Detailed description
  60. @c man begin DETAILED DESCRIPTION
  61. The transcoding process in @command{ffmpeg} for each output can be described by
  62. the following diagram:
  63. @verbatim
  64. _______ ______________
  65. | | | |
  66. | input | demuxer | encoded data | decoder
  67. | file | ---------> | packets | -----+
  68. |_______| |______________| |
  69. v
  70. _________
  71. | |
  72. | decoded |
  73. | frames |
  74. |_________|
  75. ________ ______________ |
  76. | | | | |
  77. | output | <-------- | encoded data | <----+
  78. | file | muxer | packets | encoder
  79. |________| |______________|
  80. @end verbatim
  81. @command{ffmpeg} calls the libavformat library (containing demuxers) to read
  82. input files and get packets containing encoded data from them. When there are
  83. multiple input files, @command{ffmpeg} tries to keep them synchronized by
  84. tracking lowest timestamp on any active input stream.
  85. Encoded packets are then passed to the decoder (unless streamcopy is selected
  86. for the stream, see further for a description). The decoder produces
  87. uncompressed frames (raw video/PCM audio/...) which can be processed further by
  88. filtering (see next section). After filtering, the frames are passed to the
  89. encoder, which encodes them and outputs encoded packets. Finally those are
  90. passed to the muxer, which writes the encoded packets to the output file.
  91. @section Filtering
  92. Before encoding, @command{ffmpeg} can process raw audio and video frames using
  93. filters from the libavfilter library. Several chained filters form a filter
  94. graph. @command{ffmpeg} distinguishes between two types of filtergraphs:
  95. simple and complex.
  96. @subsection Simple filtergraphs
  97. Simple filtergraphs are those that have exactly one input and output, both of
  98. the same type. In the above diagram they can be represented by simply inserting
  99. an additional step between decoding and encoding:
  100. @verbatim
  101. _________ ______________
  102. | | | |
  103. | decoded | | encoded data |
  104. | frames |\ _ | packets |
  105. |_________| \ /||______________|
  106. \ __________ /
  107. simple _\|| | / encoder
  108. filtergraph | filtered |/
  109. | frames |
  110. |__________|
  111. @end verbatim
  112. Simple filtergraphs are configured with the per-stream @option{-filter} option
  113. (with @option{-vf} and @option{-af} aliases for video and audio respectively).
  114. A simple filtergraph for video can look for example like this:
  115. @verbatim
  116. _______ _____________ _______ ________
  117. | | | | | | | |
  118. | input | ---> | deinterlace | ---> | scale | ---> | output |
  119. |_______| |_____________| |_______| |________|
  120. @end verbatim
  121. Note that some filters change frame properties but not frame contents. E.g. the
  122. @code{fps} filter in the example above changes number of frames, but does not
  123. touch the frame contents. Another example is the @code{setpts} filter, which
  124. only sets timestamps and otherwise passes the frames unchanged.
  125. @subsection Complex filtergraphs
  126. Complex filtergraphs are those which cannot be described as simply a linear
  127. processing chain applied to one stream. This is the case, for example, when the graph has
  128. more than one input and/or output, or when output stream type is different from
  129. input. They can be represented with the following diagram:
  130. @verbatim
  131. _________
  132. | |
  133. | input 0 |\ __________
  134. |_________| \ | |
  135. \ _________ /| output 0 |
  136. \ | | / |__________|
  137. _________ \| complex | /
  138. | | | |/
  139. | input 1 |---->| filter |\
  140. |_________| | | \ __________
  141. /| graph | \ | |
  142. / | | \| output 1 |
  143. _________ / |_________| |__________|
  144. | | /
  145. | input 2 |/
  146. |_________|
  147. @end verbatim
  148. Complex filtergraphs are configured with the @option{-filter_complex} option.
  149. Note that this option is global, since a complex filtergraph, by its nature,
  150. cannot be unambiguously associated with a single stream or file.
  151. The @option{-lavfi} option is equivalent to @option{-filter_complex}.
  152. A trivial example of a complex filtergraph is the @code{overlay} filter, which
  153. has two video inputs and one video output, containing one video overlaid on top
  154. of the other. Its audio counterpart is the @code{amix} filter.
  155. @section Stream copy
  156. Stream copy is a mode selected by supplying the @code{copy} parameter to the
  157. @option{-codec} option. It makes @command{ffmpeg} omit the decoding and encoding
  158. step for the specified stream, so it does only demuxing and muxing. It is useful
  159. for changing the container format or modifying container-level metadata. The
  160. diagram above will, in this case, simplify to this:
  161. @verbatim
  162. _______ ______________ ________
  163. | | | | | |
  164. | input | demuxer | encoded data | muxer | output |
  165. | file | ---------> | packets | -------> | file |
  166. |_______| |______________| |________|
  167. @end verbatim
  168. Since there is no decoding or encoding, it is very fast and there is no quality
  169. loss. However, it might not work in some cases because of many factors. Applying
  170. filters is obviously also impossible, since filters work on uncompressed data.
  171. @c man end DETAILED DESCRIPTION
  172. @chapter Stream selection
  173. @c man begin STREAM SELECTION
  174. @command{ffmpeg} provides the @code{-map} option for manual control of stream selection in each
  175. output file. Users can skip @code{-map} and let ffmpeg perform automatic stream selection as
  176. described below. The @code{-vn / -an / -sn / -dn} options can be used to skip inclusion of
  177. video, audio, subtitle and data streams respectively, whether manually mapped or automatically
  178. selected, except for those streams which are outputs of complex filtergraphs.
  179. @section Description
  180. The sub-sections that follow describe the various rules that are involved in stream selection.
  181. The examples that follow next show how these rules are applied in practice.
  182. While every effort is made to accurately reflect the behavior of the program, FFmpeg is under
  183. continuous development and the code may have changed since the time of this writing.
  184. @subsection Automatic stream selection
  185. In the absence of any map options for a particular output file, ffmpeg inspects the output
  186. format to check which type of streams can be included in it, viz. video, audio and/or
  187. subtitles. For each acceptable stream type, ffmpeg will pick one stream, when available,
  188. from among all the inputs.
  189. It will select that stream based upon the following criteria:
  190. @itemize
  191. @item
  192. for video, it is the stream with the highest resolution,
  193. @item
  194. for audio, it is the stream with the most channels,
  195. @item
  196. for subtitles, it is the first subtitle stream found but there's a caveat.
  197. The output format's default subtitle encoder can be either text-based or image-based,
  198. and only a subtitle stream of the same type will be chosen.
  199. @end itemize
  200. In the case where several streams of the same type rate equally, the stream with the lowest
  201. index is chosen.
  202. Data or attachment streams are not automatically selected and can only be included
  203. using @code{-map}.
  204. @subsection Manual stream selection
  205. When @code{-map} is used, only user-mapped streams are included in that output file,
  206. with one possible exception for filtergraph outputs described below.
  207. @subsection Complex filtergraphs
  208. If there are any complex filtergraph output streams with unlabeled pads, they will be added
  209. to the first output file. This will lead to a fatal error if the stream type is not supported
  210. by the output format. In the absence of the map option, the inclusion of these streams leads
  211. to the automatic stream selection of their types being skipped. If map options are present,
  212. these filtergraph streams are included in addition to the mapped streams.
  213. Complex filtergraph output streams with labeled pads must be mapped once and exactly once.
  214. @subsection Stream handling
  215. Stream handling is independent of stream selection, with an exception for subtitles described
  216. below. Stream handling is set via the @code{-codec} option addressed to streams within a
  217. specific @emph{output} file. In particular, codec options are applied by ffmpeg after the
  218. stream selection process and thus do not influence the latter. If no @code{-codec} option is
  219. specified for a stream type, ffmpeg will select the default encoder registered by the output
  220. file muxer.
  221. An exception exists for subtitles. If a subtitle encoder is specified for an output file, the
  222. first subtitle stream found of any type, text or image, will be included. ffmpeg does not validate
  223. if the specified encoder can convert the selected stream or if the converted stream is acceptable
  224. within the output format. This applies generally as well: when the user sets an encoder manually,
  225. the stream selection process cannot check if the encoded stream can be muxed into the output file.
  226. If it cannot, ffmpeg will abort and @emph{all} output files will fail to be processed.
  227. @section Examples
  228. The following examples illustrate the behavior, quirks and limitations of ffmpeg's stream
  229. selection methods.
  230. They assume the following three input files.
  231. @verbatim
  232. input file 'A.avi'
  233. stream 0: video 640x360
  234. stream 1: audio 2 channels
  235. input file 'B.mp4'
  236. stream 0: video 1920x1080
  237. stream 1: audio 2 channels
  238. stream 2: subtitles (text)
  239. stream 3: audio 5.1 channels
  240. stream 4: subtitles (text)
  241. input file 'C.mkv'
  242. stream 0: video 1280x720
  243. stream 1: audio 2 channels
  244. stream 2: subtitles (image)
  245. @end verbatim
  246. @subsubheading Example: automatic stream selection
  247. @example
  248. ffmpeg -i A.avi -i B.mp4 out1.mkv out2.wav -map 1:a -c:a copy out3.mov
  249. @end example
  250. There are three output files specified, and for the first two, no @code{-map} options
  251. are set, so ffmpeg will select streams for these two files automatically.
  252. @file{out1.mkv} is a Matroska container file and accepts video, audio and subtitle streams,
  253. so ffmpeg will try to select one of each type.@*
  254. For video, it will select @code{stream 0} from @file{B.mp4}, which has the highest
  255. resolution among all the input video streams.@*
  256. For audio, it will select @code{stream 3} from @file{B.mp4}, since it has the greatest
  257. number of channels.@*
  258. For subtitles, it will select @code{stream 2} from @file{B.mp4}, which is the first subtitle
  259. stream from among @file{A.avi} and @file{B.mp4}.
  260. @file{out2.wav} accepts only audio streams, so only @code{stream 3} from @file{B.mp4} is
  261. selected.
  262. For @file{out3.mov}, since a @code{-map} option is set, no automatic stream selection will
  263. occur. The @code{-map 1:a} option will select all audio streams from the second input
  264. @file{B.mp4}. No other streams will be included in this output file.
  265. For the first two outputs, all included streams will be transcoded. The encoders chosen will
  266. be the default ones registered by each output format, which may not match the codec of the
  267. selected input streams.
  268. For the third output, codec option for audio streams has been set
  269. to @code{copy}, so no decoding-filtering-encoding operations will occur, or @emph{can} occur.
  270. Packets of selected streams shall be conveyed from the input file and muxed within the output
  271. file.
  272. @subsubheading Example: automatic subtitles selection
  273. @example
  274. ffmpeg -i C.mkv out1.mkv -c:s dvdsub -an out2.mkv
  275. @end example
  276. Although @file{out1.mkv} is a Matroska container file which accepts subtitle streams, only a
  277. video and audio stream shall be selected. The subtitle stream of @file{C.mkv} is image-based
  278. and the default subtitle encoder of the Matroska muxer is text-based, so a transcode operation
  279. for the subtitles is expected to fail and hence the stream isn't selected. However, in
  280. @file{out2.mkv}, a subtitle encoder is specified in the command and so, the subtitle stream is
  281. selected, in addition to the video stream. The presence of @code{-an} disables audio stream
  282. selection for @file{out2.mkv}.
  283. @subsubheading Example: unlabeled filtergraph outputs
  284. @example
  285. ffmpeg -i A.avi -i C.mkv -i B.mp4 -filter_complex "overlay" out1.mp4 out2.srt
  286. @end example
  287. A filtergraph is setup here using the @code{-filter_complex} option and consists of a single
  288. video filter. The @code{overlay} filter requires exactly two video inputs, but none are
  289. specified, so the first two available video streams are used, those of @file{A.avi} and
  290. @file{C.mkv}. The output pad of the filter has no label and so is sent to the first output file
  291. @file{out1.mp4}. Due to this, automatic selection of the video stream is skipped, which would
  292. have selected the stream in @file{B.mp4}. The audio stream with most channels viz. @code{stream 3}
  293. in @file{B.mp4}, is chosen automatically. No subtitle stream is chosen however, since the MP4
  294. format has no default subtitle encoder registered, and the user hasn't specified a subtitle encoder.
  295. The 2nd output file, @file{out2.srt}, only accepts text-based subtitle streams. So, even though
  296. the first subtitle stream available belongs to @file{C.mkv}, it is image-based and hence skipped.
  297. The selected stream, @code{stream 2} in @file{B.mp4}, is the first text-based subtitle stream.
  298. @subsubheading Example: labeled filtergraph outputs
  299. @example
  300. ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0[outv];overlay;aresample" \
  301. -map '[outv]' -an out1.mp4 \
  302. out2.mkv \
  303. -map '[outv]' -map 1:a:0 out3.mkv
  304. @end example
  305. The above command will fail, as the output pad labelled @code{[outv]} has been mapped twice.
  306. None of the output files shall be processed.
  307. @example
  308. ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0[outv];overlay;aresample" \
  309. -an out1.mp4 \
  310. out2.mkv \
  311. -map 1:a:0 out3.mkv
  312. @end example
  313. This command above will also fail as the hue filter output has a label, @code{[outv]},
  314. and hasn't been mapped anywhere.
  315. The command should be modified as follows,
  316. @example
  317. ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0,split=2[outv1][outv2];overlay;aresample" \
  318. -map '[outv1]' -an out1.mp4 \
  319. out2.mkv \
  320. -map '[outv2]' -map 1:a:0 out3.mkv
  321. @end example
  322. The video stream from @file{B.mp4} is sent to the hue filter, whose output is cloned once using
  323. the split filter, and both outputs labelled. Then a copy each is mapped to the first and third
  324. output files.
  325. The overlay filter, requiring two video inputs, uses the first two unused video streams. Those
  326. are the streams from @file{A.avi} and @file{C.mkv}. The overlay output isn't labelled, so it is
  327. sent to the first output file @file{out1.mp4}, regardless of the presence of the @code{-map} option.
  328. The aresample filter is sent the first unused audio stream, that of @file{A.avi}. Since this filter
  329. output is also unlabelled, it too is mapped to the first output file. The presence of @code{-an}
  330. only suppresses automatic or manual stream selection of audio streams, not outputs sent from
  331. filtergraphs. Both these mapped streams shall be ordered before the mapped stream in @file{out1.mp4}.
  332. The video, audio and subtitle streams mapped to @code{out2.mkv} are entirely determined by
  333. automatic stream selection.
  334. @file{out3.mkv} consists of the cloned video output from the hue filter and the first audio
  335. stream from @file{B.mp4}.
  336. @*
  337. @c man end STREAM SELECTION
  338. @chapter Options
  339. @c man begin OPTIONS
  340. @include fftools-common-opts.texi
  341. @section Main options
  342. @table @option
  343. @item -f @var{fmt} (@emph{input/output})
  344. Force input or output file format. The format is normally auto detected for input
  345. files and guessed from the file extension for output files, so this option is not
  346. needed in most cases.
  347. @item -i @var{url} (@emph{input})
  348. input file url
  349. @item -y (@emph{global})
  350. Overwrite output files without asking.
  351. @item -n (@emph{global})
  352. Do not overwrite output files, and exit immediately if a specified
  353. output file already exists.
  354. @item -stream_loop @var{number} (@emph{input})
  355. Set number of times input stream shall be looped. Loop 0 means no loop,
  356. loop -1 means infinite loop.
  357. @item -c[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
  358. @itemx -codec[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
  359. Select an encoder (when used before an output file) or a decoder (when used
  360. before an input file) for one or more streams. @var{codec} is the name of a
  361. decoder/encoder or a special value @code{copy} (output only) to indicate that
  362. the stream is not to be re-encoded.
  363. For example
  364. @example
  365. ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT
  366. @end example
  367. encodes all video streams with libx264 and copies all audio streams.
  368. For each stream, the last matching @code{c} option is applied, so
  369. @example
  370. ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT
  371. @end example
  372. will copy all the streams except the second video, which will be encoded with
  373. libx264, and the 138th audio, which will be encoded with libvorbis.
  374. @item -t @var{duration} (@emph{input/output})
  375. When used as an input option (before @code{-i}), limit the @var{duration} of
  376. data read from the input file.
  377. When used as an output option (before an output url), stop writing the
  378. output after its duration reaches @var{duration}.
  379. @var{duration} must be a time duration specification,
  380. see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
  381. -to and -t are mutually exclusive and -t has priority.
  382. @item -to @var{position} (@emph{input/output})
  383. Stop writing the output or reading the input at @var{position}.
  384. @var{position} must be a time duration specification,
  385. see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
  386. -to and -t are mutually exclusive and -t has priority.
  387. @item -fs @var{limit_size} (@emph{output})
  388. Set the file size limit, expressed in bytes. No further chunk of bytes is written
  389. after the limit is exceeded. The size of the output file is slightly more than the
  390. requested file size.
  391. @item -ss @var{position} (@emph{input/output})
  392. When used as an input option (before @code{-i}), seeks in this input file to
  393. @var{position}. Note that in most formats it is not possible to seek exactly,
  394. so @command{ffmpeg} will seek to the closest seek point before @var{position}.
  395. When transcoding and @option{-accurate_seek} is enabled (the default), this
  396. extra segment between the seek point and @var{position} will be decoded and
  397. discarded. When doing stream copy or when @option{-noaccurate_seek} is used, it
  398. will be preserved.
  399. When used as an output option (before an output url), decodes but discards
  400. input until the timestamps reach @var{position}.
  401. @var{position} must be a time duration specification,
  402. see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
  403. @item -sseof @var{position} (@emph{input})
  404. Like the @code{-ss} option but relative to the "end of file". That is negative
  405. values are earlier in the file, 0 is at EOF.
  406. @item -itsoffset @var{offset} (@emph{input})
  407. Set the input time offset.
  408. @var{offset} must be a time duration specification,
  409. see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
  410. The offset is added to the timestamps of the input files. Specifying
  411. a positive offset means that the corresponding streams are delayed by
  412. the time duration specified in @var{offset}.
  413. @item -itsscale @var{scale} (@emph{input,per-stream})
  414. Rescale input timestamps. @var{scale} should be a floating point number.
  415. @item -timestamp @var{date} (@emph{output})
  416. Set the recording timestamp in the container.
  417. @var{date} must be a date specification,
  418. see @ref{date syntax,,the Date section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
  419. @item -metadata[:metadata_specifier] @var{key}=@var{value} (@emph{output,per-metadata})
  420. Set a metadata key/value pair.
  421. An optional @var{metadata_specifier} may be given to set metadata
  422. on streams, chapters or programs. See @code{-map_metadata}
  423. documentation for details.
  424. This option overrides metadata set with @code{-map_metadata}. It is
  425. also possible to delete metadata by using an empty value.
  426. For example, for setting the title in the output file:
  427. @example
  428. ffmpeg -i in.avi -metadata title="my title" out.flv
  429. @end example
  430. To set the language of the first audio stream:
  431. @example
  432. ffmpeg -i INPUT -metadata:s:a:0 language=eng OUTPUT
  433. @end example
  434. @item -disposition[:stream_specifier] @var{value} (@emph{output,per-stream})
  435. Sets the disposition for a stream.
  436. This option overrides the disposition copied from the input stream. It is also
  437. possible to delete the disposition by setting it to 0.
  438. The following dispositions are recognized:
  439. @table @option
  440. @item default
  441. @item dub
  442. @item original
  443. @item comment
  444. @item lyrics
  445. @item karaoke
  446. @item forced
  447. @item hearing_impaired
  448. @item visual_impaired
  449. @item clean_effects
  450. @item attached_pic
  451. @item captions
  452. @item descriptions
  453. @item dependent
  454. @item metadata
  455. @end table
  456. For example, to make the second audio stream the default stream:
  457. @example
  458. ffmpeg -i in.mkv -c copy -disposition:a:1 default out.mkv
  459. @end example
  460. To make the second subtitle stream the default stream and remove the default
  461. disposition from the first subtitle stream:
  462. @example
  463. ffmpeg -i in.mkv -c copy -disposition:s:0 0 -disposition:s:1 default out.mkv
  464. @end example
  465. To add an embedded cover/thumbnail:
  466. @example
  467. ffmpeg -i in.mp4 -i IMAGE -map 0 -map 1 -c copy -c:v:1 png -disposition:v:1 attached_pic out.mp4
  468. @end example
  469. Not all muxers support embedded thumbnails, and those who do, only support a few formats, like JPEG or PNG.
  470. @item -program [title=@var{title}:][program_num=@var{program_num}:]st=@var{stream}[:st=@var{stream}...] (@emph{output})
  471. Creates a program with the specified @var{title}, @var{program_num} and adds the specified
  472. @var{stream}(s) to it.
  473. @item -target @var{type} (@emph{output})
  474. Specify target file type (@code{vcd}, @code{svcd}, @code{dvd}, @code{dv},
  475. @code{dv50}). @var{type} may be prefixed with @code{pal-}, @code{ntsc-} or
  476. @code{film-} to use the corresponding standard. All the format options
  477. (bitrate, codecs, buffer sizes) are then set automatically. You can just type:
  478. @example
  479. ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
  480. @end example
  481. Nevertheless you can specify additional options as long as you know
  482. they do not conflict with the standard, as in:
  483. @example
  484. ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
  485. @end example
  486. @item -dn (@emph{input/output})
  487. As an input option, blocks all data streams of a file from being filtered or
  488. being automatically selected or mapped for any output. See @code{-discard}
  489. option to disable streams individually.
  490. As an output option, disables data recording i.e. automatic selection or
  491. mapping of any data stream. For full manual control see the @code{-map}
  492. option.
  493. @item -dframes @var{number} (@emph{output})
  494. Set the number of data frames to output. This is an obsolete alias for
  495. @code{-frames:d}, which you should use instead.
  496. @item -frames[:@var{stream_specifier}] @var{framecount} (@emph{output,per-stream})
  497. Stop writing to the stream after @var{framecount} frames.
  498. @item -q[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
  499. @itemx -qscale[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
  500. Use fixed quality scale (VBR). The meaning of @var{q}/@var{qscale} is
  501. codec-dependent.
  502. If @var{qscale} is used without a @var{stream_specifier} then it applies only
  503. to the video stream, this is to maintain compatibility with previous behavior
  504. and as specifying the same codec specific value to 2 different codecs that is
  505. audio and video generally is not what is intended when no stream_specifier is
  506. used.
  507. @anchor{filter_option}
  508. @item -filter[:@var{stream_specifier}] @var{filtergraph} (@emph{output,per-stream})
  509. Create the filtergraph specified by @var{filtergraph} and use it to
  510. filter the stream.
  511. @var{filtergraph} is a description of the filtergraph to apply to
  512. the stream, and must have a single input and a single output of the
  513. same type of the stream. In the filtergraph, the input is associated
  514. to the label @code{in}, and the output to the label @code{out}. See
  515. the ffmpeg-filters manual for more information about the filtergraph
  516. syntax.
  517. See the @ref{filter_complex_option,,-filter_complex option} if you
  518. want to create filtergraphs with multiple inputs and/or outputs.
  519. @item -filter_script[:@var{stream_specifier}] @var{filename} (@emph{output,per-stream})
  520. This option is similar to @option{-filter}, the only difference is that its
  521. argument is the name of the file from which a filtergraph description is to be
  522. read.
  523. @item -filter_threads @var{nb_threads} (@emph{global})
  524. Defines how many threads are used to process a filter pipeline. Each pipeline
  525. will produce a thread pool with this many threads available for parallel processing.
  526. The default is the number of available CPUs.
  527. @item -pre[:@var{stream_specifier}] @var{preset_name} (@emph{output,per-stream})
  528. Specify the preset for matching stream(s).
  529. @item -stats (@emph{global})
  530. Print encoding progress/statistics. It is on by default, to explicitly
  531. disable it you need to specify @code{-nostats}.
  532. @item -progress @var{url} (@emph{global})
  533. Send program-friendly progress information to @var{url}.
  534. Progress information is written approximately every second and at the end of
  535. the encoding process. It is made of "@var{key}=@var{value}" lines. @var{key}
  536. consists of only alphanumeric characters. The last key of a sequence of
  537. progress information is always "progress".
  538. @anchor{stdin option}
  539. @item -stdin
  540. Enable interaction on standard input. On by default unless standard input is
  541. used as an input. To explicitly disable interaction you need to specify
  542. @code{-nostdin}.
  543. Disabling interaction on standard input is useful, for example, if
  544. ffmpeg is in the background process group. Roughly the same result can
  545. be achieved with @code{ffmpeg ... < /dev/null} but it requires a
  546. shell.
  547. @item -debug_ts (@emph{global})
  548. Print timestamp information. It is off by default. This option is
  549. mostly useful for testing and debugging purposes, and the output
  550. format may change from one version to another, so it should not be
  551. employed by portable scripts.
  552. See also the option @code{-fdebug ts}.
  553. @item -attach @var{filename} (@emph{output})
  554. Add an attachment to the output file. This is supported by a few formats
  555. like Matroska for e.g. fonts used in rendering subtitles. Attachments
  556. are implemented as a specific type of stream, so this option will add
  557. a new stream to the file. It is then possible to use per-stream options
  558. on this stream in the usual way. Attachment streams created with this
  559. option will be created after all the other streams (i.e. those created
  560. with @code{-map} or automatic mappings).
  561. Note that for Matroska you also have to set the mimetype metadata tag:
  562. @example
  563. ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv
  564. @end example
  565. (assuming that the attachment stream will be third in the output file).
  566. @item -dump_attachment[:@var{stream_specifier}] @var{filename} (@emph{input,per-stream})
  567. Extract the matching attachment stream into a file named @var{filename}. If
  568. @var{filename} is empty, then the value of the @code{filename} metadata tag
  569. will be used.
  570. E.g. to extract the first attachment to a file named 'out.ttf':
  571. @example
  572. ffmpeg -dump_attachment:t:0 out.ttf -i INPUT
  573. @end example
  574. To extract all attachments to files determined by the @code{filename} tag:
  575. @example
  576. ffmpeg -dump_attachment:t "" -i INPUT
  577. @end example
  578. Technical note -- attachments are implemented as codec extradata, so this
  579. option can actually be used to extract extradata from any stream, not just
  580. attachments.
  581. @item -noautorotate
  582. Disable automatically rotating video based on file metadata.
  583. @end table
  584. @section Video Options
  585. @table @option
  586. @item -vframes @var{number} (@emph{output})
  587. Set the number of video frames to output. This is an obsolete alias for
  588. @code{-frames:v}, which you should use instead.
  589. @item -r[:@var{stream_specifier}] @var{fps} (@emph{input/output,per-stream})
  590. Set frame rate (Hz value, fraction or abbreviation).
  591. As an input option, ignore any timestamps stored in the file and instead
  592. generate timestamps assuming constant frame rate @var{fps}.
  593. This is not the same as the @option{-framerate} option used for some input formats
  594. like image2 or v4l2 (it used to be the same in older versions of FFmpeg).
  595. If in doubt use @option{-framerate} instead of the input option @option{-r}.
  596. As an output option, duplicate or drop input frames to achieve constant output
  597. frame rate @var{fps}.
  598. @item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream})
  599. Set frame size.
  600. As an input option, this is a shortcut for the @option{video_size} private
  601. option, recognized by some demuxers for which the frame size is either not
  602. stored in the file or is configurable -- e.g. raw video or video grabbers.
  603. As an output option, this inserts the @code{scale} video filter to the
  604. @emph{end} of the corresponding filtergraph. Please use the @code{scale} filter
  605. directly to insert it at the beginning or some other place.
  606. The format is @samp{wxh} (default - same as source).
  607. @item -aspect[:@var{stream_specifier}] @var{aspect} (@emph{output,per-stream})
  608. Set the video display aspect ratio specified by @var{aspect}.
  609. @var{aspect} can be a floating point number string, or a string of the
  610. form @var{num}:@var{den}, where @var{num} and @var{den} are the
  611. numerator and denominator of the aspect ratio. For example "4:3",
  612. "16:9", "1.3333", and "1.7777" are valid argument values.
  613. If used together with @option{-vcodec copy}, it will affect the aspect ratio
  614. stored at container level, but not the aspect ratio stored in encoded
  615. frames, if it exists.
  616. @item -vn (@emph{input/output})
  617. As an input option, blocks all video streams of a file from being filtered or
  618. being automatically selected or mapped for any output. See @code{-discard}
  619. option to disable streams individually.
  620. As an output option, disables video recording i.e. automatic selection or
  621. mapping of any video stream. For full manual control see the @code{-map}
  622. option.
  623. @item -vcodec @var{codec} (@emph{output})
  624. Set the video codec. This is an alias for @code{-codec:v}.
  625. @item -pass[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
  626. Select the pass number (1 or 2). It is used to do two-pass
  627. video encoding. The statistics of the video are recorded in the first
  628. pass into a log file (see also the option -passlogfile),
  629. and in the second pass that log file is used to generate the video
  630. at the exact requested bitrate.
  631. On pass 1, you may just deactivate audio and set output to null,
  632. examples for Windows and Unix:
  633. @example
  634. ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
  635. ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null
  636. @end example
  637. @item -passlogfile[:@var{stream_specifier}] @var{prefix} (@emph{output,per-stream})
  638. Set two-pass log file name prefix to @var{prefix}, the default file name
  639. prefix is ``ffmpeg2pass''. The complete file name will be
  640. @file{PREFIX-N.log}, where N is a number specific to the output
  641. stream
  642. @item -vf @var{filtergraph} (@emph{output})
  643. Create the filtergraph specified by @var{filtergraph} and use it to
  644. filter the stream.
  645. This is an alias for @code{-filter:v}, see the @ref{filter_option,,-filter option}.
  646. @end table
  647. @section Advanced Video options
  648. @table @option
  649. @item -pix_fmt[:@var{stream_specifier}] @var{format} (@emph{input/output,per-stream})
  650. Set pixel format. Use @code{-pix_fmts} to show all the supported
  651. pixel formats.
  652. If the selected pixel format can not be selected, ffmpeg will print a
  653. warning and select the best pixel format supported by the encoder.
  654. If @var{pix_fmt} is prefixed by a @code{+}, ffmpeg will exit with an error
  655. if the requested pixel format can not be selected, and automatic conversions
  656. inside filtergraphs are disabled.
  657. If @var{pix_fmt} is a single @code{+}, ffmpeg selects the same pixel format
  658. as the input (or graph output) and automatic conversions are disabled.
  659. @item -sws_flags @var{flags} (@emph{input/output})
  660. Set SwScaler flags.
  661. @item -rc_override[:@var{stream_specifier}] @var{override} (@emph{output,per-stream})
  662. Rate control override for specific intervals, formatted as "int,int,int"
  663. list separated with slashes. Two first values are the beginning and
  664. end frame numbers, last one is quantizer to use if positive, or quality
  665. factor if negative.
  666. @item -ilme
  667. Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
  668. Use this option if your input file is interlaced and you want
  669. to keep the interlaced format for minimum losses.
  670. The alternative is to deinterlace the input stream with
  671. @option{-deinterlace}, but deinterlacing introduces losses.
  672. @item -psnr
  673. Calculate PSNR of compressed frames.
  674. @item -vstats
  675. Dump video coding statistics to @file{vstats_HHMMSS.log}.
  676. @item -vstats_file @var{file}
  677. Dump video coding statistics to @var{file}.
  678. @item -vstats_version @var{file}
  679. Specifies which version of the vstats format to use. Default is 2.
  680. version = 1 :
  681. @code{frame= %5d q= %2.1f PSNR= %6.2f f_size= %6d s_size= %8.0fkB time= %0.3f br= %7.1fkbits/s avg_br= %7.1fkbits/s}
  682. version > 1:
  683. @code{out= %2d st= %2d frame= %5d q= %2.1f PSNR= %6.2f f_size= %6d s_size= %8.0fkB time= %0.3f br= %7.1fkbits/s avg_br= %7.1fkbits/s}
  684. @item -top[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
  685. top=1/bottom=0/auto=-1 field first
  686. @item -dc @var{precision}
  687. Intra_dc_precision.
  688. @item -vtag @var{fourcc/tag} (@emph{output})
  689. Force video tag/fourcc. This is an alias for @code{-tag:v}.
  690. @item -qphist (@emph{global})
  691. Show QP histogram
  692. @item -vbsf @var{bitstream_filter}
  693. Deprecated see -bsf
  694. @item -force_key_frames[:@var{stream_specifier}] @var{time}[,@var{time}...] (@emph{output,per-stream})
  695. @item -force_key_frames[:@var{stream_specifier}] expr:@var{expr} (@emph{output,per-stream})
  696. @item -force_key_frames[:@var{stream_specifier}] source (@emph{output,per-stream})
  697. @var{force_key_frames} can take arguments of the following form:
  698. @table @option
  699. @item @var{time}[,@var{time}...]
  700. If the argument consists of timestamps, ffmpeg will round the specified times to the nearest
  701. output timestamp as per the encoder time base and force a keyframe at the first frame having
  702. timestamp equal or greater than the computed timestamp. Note that if the encoder time base is too
  703. coarse, then the keyframes may be forced on frames with timestamps lower than the specified time.
  704. The default encoder time base is the inverse of the output framerate but may be set otherwise
  705. via @code{-enc_time_base}.
  706. If one of the times is "@code{chapters}[@var{delta}]", it is expanded into
  707. the time of the beginning of all chapters in the file, shifted by
  708. @var{delta}, expressed as a time in seconds.
  709. This option can be useful to ensure that a seek point is present at a
  710. chapter mark or any other designated place in the output file.
  711. For example, to insert a key frame at 5 minutes, plus key frames 0.1 second
  712. before the beginning of every chapter:
  713. @example
  714. -force_key_frames 0:05:00,chapters-0.1
  715. @end example
  716. @item expr:@var{expr}
  717. If the argument is prefixed with @code{expr:}, the string @var{expr}
  718. is interpreted like an expression and is evaluated for each frame. A
  719. key frame is forced in case the evaluation is non-zero.
  720. The expression in @var{expr} can contain the following constants:
  721. @table @option
  722. @item n
  723. the number of current processed frame, starting from 0
  724. @item n_forced
  725. the number of forced frames
  726. @item prev_forced_n
  727. the number of the previous forced frame, it is @code{NAN} when no
  728. keyframe was forced yet
  729. @item prev_forced_t
  730. the time of the previous forced frame, it is @code{NAN} when no
  731. keyframe was forced yet
  732. @item t
  733. the time of the current processed frame
  734. @end table
  735. For example to force a key frame every 5 seconds, you can specify:
  736. @example
  737. -force_key_frames expr:gte(t,n_forced*5)
  738. @end example
  739. To force a key frame 5 seconds after the time of the last forced one,
  740. starting from second 13:
  741. @example
  742. -force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5))
  743. @end example
  744. @item source
  745. If the argument is @code{source}, ffmpeg will force a key frame if
  746. the current frame being encoded is marked as a key frame in its source.
  747. @end table
  748. Note that forcing too many keyframes is very harmful for the lookahead
  749. algorithms of certain encoders: using fixed-GOP options or similar
  750. would be more efficient.
  751. @item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream})
  752. When doing stream copy, copy also non-key frames found at the
  753. beginning.
  754. @item -init_hw_device @var{type}[=@var{name}][:@var{device}[,@var{key=value}...]]
  755. Initialise a new hardware device of type @var{type} called @var{name}, using the
  756. given device parameters.
  757. If no name is specified it will receive a default name of the form "@var{type}%d".
  758. The meaning of @var{device} and the following arguments depends on the
  759. device type:
  760. @table @option
  761. @item cuda
  762. @var{device} is the number of the CUDA device.
  763. @item dxva2
  764. @var{device} is the number of the Direct3D 9 display adapter.
  765. @item vaapi
  766. @var{device} is either an X11 display name or a DRM render node.
  767. If not specified, it will attempt to open the default X11 display (@emph{$DISPLAY})
  768. and then the first DRM render node (@emph{/dev/dri/renderD128}).
  769. @item vdpau
  770. @var{device} is an X11 display name.
  771. If not specified, it will attempt to open the default X11 display (@emph{$DISPLAY}).
  772. @item qsv
  773. @var{device} selects a value in @samp{MFX_IMPL_*}. Allowed values are:
  774. @table @option
  775. @item auto
  776. @item sw
  777. @item hw
  778. @item auto_any
  779. @item hw_any
  780. @item hw2
  781. @item hw3
  782. @item hw4
  783. @end table
  784. If not specified, @samp{auto_any} is used.
  785. (Note that it may be easier to achieve the desired result for QSV by creating the
  786. platform-appropriate subdevice (@samp{dxva2} or @samp{vaapi}) and then deriving a
  787. QSV device from that.)
  788. @item opencl
  789. @var{device} selects the platform and device as @emph{platform_index.device_index}.
  790. The set of devices can also be filtered using the key-value pairs to find only
  791. devices matching particular platform or device strings.
  792. The strings usable as filters are:
  793. @table @option
  794. @item platform_profile
  795. @item platform_version
  796. @item platform_name
  797. @item platform_vendor
  798. @item platform_extensions
  799. @item device_name
  800. @item device_vendor
  801. @item driver_version
  802. @item device_version
  803. @item device_profile
  804. @item device_extensions
  805. @item device_type
  806. @end table
  807. The indices and filters must together uniquely select a device.
  808. Examples:
  809. @table @emph
  810. @item -init_hw_device opencl:0.1
  811. Choose the second device on the first platform.
  812. @item -init_hw_device opencl:,device_name=Foo9000
  813. Choose the device with a name containing the string @emph{Foo9000}.
  814. @item -init_hw_device opencl:1,device_type=gpu,device_extensions=cl_khr_fp16
  815. Choose the GPU device on the second platform supporting the @emph{cl_khr_fp16}
  816. extension.
  817. @end table
  818. @item vulkan
  819. If @var{device} is an integer, it selects the device by its index in a
  820. system-dependent list of devices. If @var{device} is any other string, it
  821. selects the first device with a name containing that string as a substring.
  822. The following options are recognized:
  823. @table @option
  824. @item debug
  825. If set to 1, enables the validation layer, if installed.
  826. @item linear_images
  827. If set to 1, images allocated by the hwcontext will be linear and locally mappable.
  828. @item instance_extensions
  829. A plus separated list of additional instance extensions to enable.
  830. @item device_extensions
  831. A plus separated list of additional device extensions to enable.
  832. @end table
  833. Examples:
  834. @table @emph
  835. @item -init_hw_device vulkan:1
  836. Choose the second device on the system.
  837. @item -init_hw_device vulkan:RADV
  838. Choose the first device with a name containing the string @emph{RADV}.
  839. @item -init_hw_device vulkan:0,instance_extensions=VK_KHR_wayland_surface+VK_KHR_xcb_surface
  840. Choose the first device and enable the Wayland and XCB instance extensions.
  841. @end table
  842. @end table
  843. @item -init_hw_device @var{type}[=@var{name}]@@@var{source}
  844. Initialise a new hardware device of type @var{type} called @var{name},
  845. deriving it from the existing device with the name @var{source}.
  846. @item -init_hw_device list
  847. List all hardware device types supported in this build of ffmpeg.
  848. @item -filter_hw_device @var{name}
  849. Pass the hardware device called @var{name} to all filters in any filter graph.
  850. This can be used to set the device to upload to with the @code{hwupload} filter,
  851. or the device to map to with the @code{hwmap} filter. Other filters may also
  852. make use of this parameter when they require a hardware device. Note that this
  853. is typically only required when the input is not already in hardware frames -
  854. when it is, filters will derive the device they require from the context of the
  855. frames they receive as input.
  856. This is a global setting, so all filters will receive the same device.
  857. @item -hwaccel[:@var{stream_specifier}] @var{hwaccel} (@emph{input,per-stream})
  858. Use hardware acceleration to decode the matching stream(s). The allowed values
  859. of @var{hwaccel} are:
  860. @table @option
  861. @item none
  862. Do not use any hardware acceleration (the default).
  863. @item auto
  864. Automatically select the hardware acceleration method.
  865. @item vdpau
  866. Use VDPAU (Video Decode and Presentation API for Unix) hardware acceleration.
  867. @item dxva2
  868. Use DXVA2 (DirectX Video Acceleration) hardware acceleration.
  869. @item vaapi
  870. Use VAAPI (Video Acceleration API) hardware acceleration.
  871. @item qsv
  872. Use the Intel QuickSync Video acceleration for video transcoding.
  873. Unlike most other values, this option does not enable accelerated decoding (that
  874. is used automatically whenever a qsv decoder is selected), but accelerated
  875. transcoding, without copying the frames into the system memory.
  876. For it to work, both the decoder and the encoder must support QSV acceleration
  877. and no filters must be used.
  878. @end table
  879. This option has no effect if the selected hwaccel is not available or not
  880. supported by the chosen decoder.
  881. Note that most acceleration methods are intended for playback and will not be
  882. faster than software decoding on modern CPUs. Additionally, @command{ffmpeg}
  883. will usually need to copy the decoded frames from the GPU memory into the system
  884. memory, resulting in further performance loss. This option is thus mainly
  885. useful for testing.
  886. @item -hwaccel_device[:@var{stream_specifier}] @var{hwaccel_device} (@emph{input,per-stream})
  887. Select a device to use for hardware acceleration.
  888. This option only makes sense when the @option{-hwaccel} option is also specified.
  889. It can either refer to an existing device created with @option{-init_hw_device}
  890. by name, or it can create a new device as if
  891. @samp{-init_hw_device} @var{type}:@var{hwaccel_device}
  892. were called immediately before.
  893. @item -hwaccels
  894. List all hardware acceleration methods supported in this build of ffmpeg.
  895. @end table
  896. @section Audio Options
  897. @table @option
  898. @item -aframes @var{number} (@emph{output})
  899. Set the number of audio frames to output. This is an obsolete alias for
  900. @code{-frames:a}, which you should use instead.
  901. @item -ar[:@var{stream_specifier}] @var{freq} (@emph{input/output,per-stream})
  902. Set the audio sampling frequency. For output streams it is set by
  903. default to the frequency of the corresponding input stream. For input
  904. streams this option only makes sense for audio grabbing devices and raw
  905. demuxers and is mapped to the corresponding demuxer options.
  906. @item -aq @var{q} (@emph{output})
  907. Set the audio quality (codec-specific, VBR). This is an alias for -q:a.
  908. @item -ac[:@var{stream_specifier}] @var{channels} (@emph{input/output,per-stream})
  909. Set the number of audio channels. For output streams it is set by
  910. default to the number of input audio channels. For input streams
  911. this option only makes sense for audio grabbing devices and raw demuxers
  912. and is mapped to the corresponding demuxer options.
  913. @item -an (@emph{input/output})
  914. As an input option, blocks all audio streams of a file from being filtered or
  915. being automatically selected or mapped for any output. See @code{-discard}
  916. option to disable streams individually.
  917. As an output option, disables audio recording i.e. automatic selection or
  918. mapping of any audio stream. For full manual control see the @code{-map}
  919. option.
  920. @item -acodec @var{codec} (@emph{input/output})
  921. Set the audio codec. This is an alias for @code{-codec:a}.
  922. @item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream})
  923. Set the audio sample format. Use @code{-sample_fmts} to get a list
  924. of supported sample formats.
  925. @item -af @var{filtergraph} (@emph{output})
  926. Create the filtergraph specified by @var{filtergraph} and use it to
  927. filter the stream.
  928. This is an alias for @code{-filter:a}, see the @ref{filter_option,,-filter option}.
  929. @end table
  930. @section Advanced Audio options
  931. @table @option
  932. @item -atag @var{fourcc/tag} (@emph{output})
  933. Force audio tag/fourcc. This is an alias for @code{-tag:a}.
  934. @item -absf @var{bitstream_filter}
  935. Deprecated, see -bsf
  936. @item -guess_layout_max @var{channels} (@emph{input,per-stream})
  937. If some input channel layout is not known, try to guess only if it
  938. corresponds to at most the specified number of channels. For example, 2
  939. tells to @command{ffmpeg} to recognize 1 channel as mono and 2 channels as
  940. stereo but not 6 channels as 5.1. The default is to always try to guess. Use
  941. 0 to disable all guessing.
  942. @end table
  943. @section Subtitle options
  944. @table @option
  945. @item -scodec @var{codec} (@emph{input/output})
  946. Set the subtitle codec. This is an alias for @code{-codec:s}.
  947. @item -sn (@emph{input/output})
  948. As an input option, blocks all subtitle streams of a file from being filtered or
  949. being automatically selected or mapped for any output. See @code{-discard}
  950. option to disable streams individually.
  951. As an output option, disables subtitle recording i.e. automatic selection or
  952. mapping of any subtitle stream. For full manual control see the @code{-map}
  953. option.
  954. @item -sbsf @var{bitstream_filter}
  955. Deprecated, see -bsf
  956. @end table
  957. @section Advanced Subtitle options
  958. @table @option
  959. @item -fix_sub_duration
  960. Fix subtitles durations. For each subtitle, wait for the next packet in the
  961. same stream and adjust the duration of the first to avoid overlap. This is
  962. necessary with some subtitles codecs, especially DVB subtitles, because the
  963. duration in the original packet is only a rough estimate and the end is
  964. actually marked by an empty subtitle frame. Failing to use this option when
  965. necessary can result in exaggerated durations or muxing failures due to
  966. non-monotonic timestamps.
  967. Note that this option will delay the output of all data until the next
  968. subtitle packet is decoded: it may increase memory consumption and latency a
  969. lot.
  970. @item -canvas_size @var{size}
  971. Set the size of the canvas used to render subtitles.
  972. @end table
  973. @section Advanced options
  974. @table @option
  975. @item -map [-]@var{input_file_id}[:@var{stream_specifier}][?][,@var{sync_file_id}[:@var{stream_specifier}]] | @var{[linklabel]} (@emph{output})
  976. Designate one or more input streams as a source for the output file. Each input
  977. stream is identified by the input file index @var{input_file_id} and
  978. the input stream index @var{input_stream_id} within the input
  979. file. Both indices start at 0. If specified,
  980. @var{sync_file_id}:@var{stream_specifier} sets which input stream
  981. is used as a presentation sync reference.
  982. The first @code{-map} option on the command line specifies the
  983. source for output stream 0, the second @code{-map} option specifies
  984. the source for output stream 1, etc.
  985. A @code{-} character before the stream identifier creates a "negative" mapping.
  986. It disables matching streams from already created mappings.
  987. A trailing @code{?} after the stream index will allow the map to be
  988. optional: if the map matches no streams the map will be ignored instead
  989. of failing. Note the map will still fail if an invalid input file index
  990. is used; such as if the map refers to a non-existent input.
  991. An alternative @var{[linklabel]} form will map outputs from complex filter
  992. graphs (see the @option{-filter_complex} option) to the output file.
  993. @var{linklabel} must correspond to a defined output link label in the graph.
  994. For example, to map ALL streams from the first input file to output
  995. @example
  996. ffmpeg -i INPUT -map 0 output
  997. @end example
  998. For example, if you have two audio streams in the first input file,
  999. these streams are identified by "0:0" and "0:1". You can use
  1000. @code{-map} to select which streams to place in an output file. For
  1001. example:
  1002. @example
  1003. ffmpeg -i INPUT -map 0:1 out.wav
  1004. @end example
  1005. will map the input stream in @file{INPUT} identified by "0:1" to
  1006. the (single) output stream in @file{out.wav}.
  1007. For example, to select the stream with index 2 from input file
  1008. @file{a.mov} (specified by the identifier "0:2"), and stream with
  1009. index 6 from input @file{b.mov} (specified by the identifier "1:6"),
  1010. and copy them to the output file @file{out.mov}:
  1011. @example
  1012. ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
  1013. @end example
  1014. To select all video and the third audio stream from an input file:
  1015. @example
  1016. ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT
  1017. @end example
  1018. To map all the streams except the second audio, use negative mappings
  1019. @example
  1020. ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT
  1021. @end example
  1022. To map the video and audio streams from the first input, and using the
  1023. trailing @code{?}, ignore the audio mapping if no audio streams exist in
  1024. the first input:
  1025. @example
  1026. ffmpeg -i INPUT -map 0:v -map 0:a? OUTPUT
  1027. @end example
  1028. To pick the English audio stream:
  1029. @example
  1030. ffmpeg -i INPUT -map 0:m:language:eng OUTPUT
  1031. @end example
  1032. Note that using this option disables the default mappings for this output file.
  1033. @item -ignore_unknown
  1034. Ignore input streams with unknown type instead of failing if copying
  1035. such streams is attempted.
  1036. @item -copy_unknown
  1037. Allow input streams with unknown type to be copied instead of failing if copying
  1038. such streams is attempted.
  1039. @item -map_channel [@var{input_file_id}.@var{stream_specifier}.@var{channel_id}|-1][?][:@var{output_file_id}.@var{stream_specifier}]
  1040. Map an audio channel from a given input to an output. If
  1041. @var{output_file_id}.@var{stream_specifier} is not set, the audio channel will
  1042. be mapped on all the audio streams.
  1043. Using "-1" instead of
  1044. @var{input_file_id}.@var{stream_specifier}.@var{channel_id} will map a muted
  1045. channel.
  1046. A trailing @code{?} will allow the map_channel to be
  1047. optional: if the map_channel matches no channel the map_channel will be ignored instead
  1048. of failing.
  1049. For example, assuming @var{INPUT} is a stereo audio file, you can switch the
  1050. two audio channels with the following command:
  1051. @example
  1052. ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT
  1053. @end example
  1054. If you want to mute the first channel and keep the second:
  1055. @example
  1056. ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT
  1057. @end example
  1058. The order of the "-map_channel" option specifies the order of the channels in
  1059. the output stream. The output channel layout is guessed from the number of
  1060. channels mapped (mono if one "-map_channel", stereo if two, etc.). Using "-ac"
  1061. in combination of "-map_channel" makes the channel gain levels to be updated if
  1062. input and output channel layouts don't match (for instance two "-map_channel"
  1063. options and "-ac 6").
  1064. You can also extract each channel of an input to specific outputs; the following
  1065. command extracts two channels of the @var{INPUT} audio stream (file 0, stream 0)
  1066. to the respective @var{OUTPUT_CH0} and @var{OUTPUT_CH1} outputs:
  1067. @example
  1068. ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1
  1069. @end example
  1070. The following example splits the channels of a stereo input into two separate
  1071. streams, which are put into the same output file:
  1072. @example
  1073. ffmpeg -i stereo.wav -map 0:0 -map 0:0 -map_channel 0.0.0:0.0 -map_channel 0.0.1:0.1 -y out.ogg
  1074. @end example
  1075. Note that currently each output stream can only contain channels from a single
  1076. input stream; you can't for example use "-map_channel" to pick multiple input
  1077. audio channels contained in different streams (from the same or different files)
  1078. and merge them into a single output stream. It is therefore not currently
  1079. possible, for example, to turn two separate mono streams into a single stereo
  1080. stream. However splitting a stereo stream into two single channel mono streams
  1081. is possible.
  1082. If you need this feature, a possible workaround is to use the @emph{amerge}
  1083. filter. For example, if you need to merge a media (here @file{input.mkv}) with 2
  1084. mono audio streams into one single stereo channel audio stream (and keep the
  1085. video stream), you can use the following command:
  1086. @example
  1087. ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv
  1088. @end example
  1089. To map the first two audio channels from the first input, and using the
  1090. trailing @code{?}, ignore the audio channel mapping if the first input is
  1091. mono instead of stereo:
  1092. @example
  1093. ffmpeg -i INPUT -map_channel 0.0.0 -map_channel 0.0.1? OUTPUT
  1094. @end example
  1095. @item -map_metadata[:@var{metadata_spec_out}] @var{infile}[:@var{metadata_spec_in}] (@emph{output,per-metadata})
  1096. Set metadata information of the next output file from @var{infile}. Note that
  1097. those are file indices (zero-based), not filenames.
  1098. Optional @var{metadata_spec_in/out} parameters specify, which metadata to copy.
  1099. A metadata specifier can have the following forms:
  1100. @table @option
  1101. @item @var{g}
  1102. global metadata, i.e. metadata that applies to the whole file
  1103. @item @var{s}[:@var{stream_spec}]
  1104. per-stream metadata. @var{stream_spec} is a stream specifier as described
  1105. in the @ref{Stream specifiers} chapter. In an input metadata specifier, the first
  1106. matching stream is copied from. In an output metadata specifier, all matching
  1107. streams are copied to.
  1108. @item @var{c}:@var{chapter_index}
  1109. per-chapter metadata. @var{chapter_index} is the zero-based chapter index.
  1110. @item @var{p}:@var{program_index}
  1111. per-program metadata. @var{program_index} is the zero-based program index.
  1112. @end table
  1113. If metadata specifier is omitted, it defaults to global.
  1114. By default, global metadata is copied from the first input file,
  1115. per-stream and per-chapter metadata is copied along with streams/chapters. These
  1116. default mappings are disabled by creating any mapping of the relevant type. A negative
  1117. file index can be used to create a dummy mapping that just disables automatic copying.
  1118. For example to copy metadata from the first stream of the input file to global metadata
  1119. of the output file:
  1120. @example
  1121. ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3
  1122. @end example
  1123. To do the reverse, i.e. copy global metadata to all audio streams:
  1124. @example
  1125. ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv
  1126. @end example
  1127. Note that simple @code{0} would work as well in this example, since global
  1128. metadata is assumed by default.
  1129. @item -map_chapters @var{input_file_index} (@emph{output})
  1130. Copy chapters from input file with index @var{input_file_index} to the next
  1131. output file. If no chapter mapping is specified, then chapters are copied from
  1132. the first input file with at least one chapter. Use a negative file index to
  1133. disable any chapter copying.
  1134. @item -benchmark (@emph{global})
  1135. Show benchmarking information at the end of an encode.
  1136. Shows real, system and user time used and maximum memory consumption.
  1137. Maximum memory consumption is not supported on all systems,
  1138. it will usually display as 0 if not supported.
  1139. @item -benchmark_all (@emph{global})
  1140. Show benchmarking information during the encode.
  1141. Shows real, system and user time used in various steps (audio/video encode/decode).
  1142. @item -timelimit @var{duration} (@emph{global})
  1143. Exit after ffmpeg has been running for @var{duration} seconds in CPU user time.
  1144. @item -dump (@emph{global})
  1145. Dump each input packet to stderr.
  1146. @item -hex (@emph{global})
  1147. When dumping packets, also dump the payload.
  1148. @item -re (@emph{input})
  1149. Read input at native frame rate. Mainly used to simulate a grab device,
  1150. or live input stream (e.g. when reading from a file). Should not be used
  1151. with actual grab devices or live input streams (where it can cause packet
  1152. loss).
  1153. By default @command{ffmpeg} attempts to read the input(s) as fast as possible.
  1154. This option will slow down the reading of the input(s) to the native frame rate
  1155. of the input(s). It is useful for real-time output (e.g. live streaming).
  1156. @item -vsync @var{parameter}
  1157. Video sync method.
  1158. For compatibility reasons old values can be specified as numbers.
  1159. Newly added values will have to be specified as strings always.
  1160. @table @option
  1161. @item 0, passthrough
  1162. Each frame is passed with its timestamp from the demuxer to the muxer.
  1163. @item 1, cfr
  1164. Frames will be duplicated and dropped to achieve exactly the requested
  1165. constant frame rate.
  1166. @item 2, vfr
  1167. Frames are passed through with their timestamp or dropped so as to
  1168. prevent 2 frames from having the same timestamp.
  1169. @item drop
  1170. As passthrough but destroys all timestamps, making the muxer generate
  1171. fresh timestamps based on frame-rate.
  1172. @item -1, auto
  1173. Chooses between 1 and 2 depending on muxer capabilities. This is the
  1174. default method.
  1175. @end table
  1176. Note that the timestamps may be further modified by the muxer, after this.
  1177. For example, in the case that the format option @option{avoid_negative_ts}
  1178. is enabled.
  1179. With -map you can select from which stream the timestamps should be
  1180. taken. You can leave either video or audio unchanged and sync the
  1181. remaining stream(s) to the unchanged one.
  1182. @item -frame_drop_threshold @var{parameter}
  1183. Frame drop threshold, which specifies how much behind video frames can
  1184. be before they are dropped. In frame rate units, so 1.0 is one frame.
  1185. The default is -1.1. One possible usecase is to avoid framedrops in case
  1186. of noisy timestamps or to increase frame drop precision in case of exact
  1187. timestamps.
  1188. @item -async @var{samples_per_second}
  1189. Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
  1190. the parameter is the maximum samples per second by which the audio is changed.
  1191. -async 1 is a special case where only the start of the audio stream is corrected
  1192. without any later correction.
  1193. Note that the timestamps may be further modified by the muxer, after this.
  1194. For example, in the case that the format option @option{avoid_negative_ts}
  1195. is enabled.
  1196. This option has been deprecated. Use the @code{aresample} audio filter instead.
  1197. @item -copyts
  1198. Do not process input timestamps, but keep their values without trying
  1199. to sanitize them. In particular, do not remove the initial start time
  1200. offset value.
  1201. Note that, depending on the @option{vsync} option or on specific muxer
  1202. processing (e.g. in case the format option @option{avoid_negative_ts}
  1203. is enabled) the output timestamps may mismatch with the input
  1204. timestamps even when this option is selected.
  1205. @item -start_at_zero
  1206. When used with @option{copyts}, shift input timestamps so they start at zero.
  1207. This means that using e.g. @code{-ss 50} will make output timestamps start at
  1208. 50 seconds, regardless of what timestamp the input file started at.
  1209. @item -copytb @var{mode}
  1210. Specify how to set the encoder timebase when stream copying. @var{mode} is an
  1211. integer numeric value, and can assume one of the following values:
  1212. @table @option
  1213. @item 1
  1214. Use the demuxer timebase.
  1215. The time base is copied to the output encoder from the corresponding input
  1216. demuxer. This is sometimes required to avoid non monotonically increasing
  1217. timestamps when copying video streams with variable frame rate.
  1218. @item 0
  1219. Use the decoder timebase.
  1220. The time base is copied to the output encoder from the corresponding input
  1221. decoder.
  1222. @item -1
  1223. Try to make the choice automatically, in order to generate a sane output.
  1224. @end table
  1225. Default value is -1.
  1226. @item -enc_time_base[:@var{stream_specifier}] @var{timebase} (@emph{output,per-stream})
  1227. Set the encoder timebase. @var{timebase} is a floating point number,
  1228. and can assume one of the following values:
  1229. @table @option
  1230. @item 0
  1231. Assign a default value according to the media type.
  1232. For video - use 1/framerate, for audio - use 1/samplerate.
  1233. @item -1
  1234. Use the input stream timebase when possible.
  1235. If an input stream is not available, the default timebase will be used.
  1236. @item >0
  1237. Use the provided number as the timebase.
  1238. This field can be provided as a ratio of two integers (e.g. 1:24, 1:48000)
  1239. or as a floating point number (e.g. 0.04166, 2.0833e-5)
  1240. @end table
  1241. Default value is 0.
  1242. @item -bitexact (@emph{input/output})
  1243. Enable bitexact mode for (de)muxer and (de/en)coder
  1244. @item -shortest (@emph{output})
  1245. Finish encoding when the shortest input stream ends.
  1246. @item -dts_delta_threshold
  1247. Timestamp discontinuity delta threshold.
  1248. @item -dts_error_threshold @var{seconds}
  1249. Timestamp error delta threshold. This threshold use to discard crazy/damaged
  1250. timestamps and the default is 30 hours which is arbitrarily picked and quite
  1251. conservative.
  1252. @item -muxdelay @var{seconds} (@emph{output})
  1253. Set the maximum demux-decode delay.
  1254. @item -muxpreload @var{seconds} (@emph{output})
  1255. Set the initial demux-decode delay.
  1256. @item -streamid @var{output-stream-index}:@var{new-value} (@emph{output})
  1257. Assign a new stream-id value to an output stream. This option should be
  1258. specified prior to the output filename to which it applies.
  1259. For the situation where multiple output files exist, a streamid
  1260. may be reassigned to a different value.
  1261. For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for
  1262. an output mpegts file:
  1263. @example
  1264. ffmpeg -i inurl -streamid 0:33 -streamid 1:36 out.ts
  1265. @end example
  1266. @item -bsf[:@var{stream_specifier}] @var{bitstream_filters} (@emph{output,per-stream})
  1267. Set bitstream filters for matching streams. @var{bitstream_filters} is
  1268. a comma-separated list of bitstream filters. Use the @code{-bsfs} option
  1269. to get the list of bitstream filters.
  1270. @example
  1271. ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264
  1272. @end example
  1273. @example
  1274. ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt
  1275. @end example
  1276. @item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{input/output,per-stream})
  1277. Force a tag/fourcc for matching streams.
  1278. @item -timecode @var{hh}:@var{mm}:@var{ss}SEP@var{ff}
  1279. Specify Timecode for writing. @var{SEP} is ':' for non drop timecode and ';'
  1280. (or '.') for drop.
  1281. @example
  1282. ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg
  1283. @end example
  1284. @anchor{filter_complex_option}
  1285. @item -filter_complex @var{filtergraph} (@emph{global})
  1286. Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
  1287. outputs. For simple graphs -- those with one input and one output of the same
  1288. type -- see the @option{-filter} options. @var{filtergraph} is a description of
  1289. the filtergraph, as described in the ``Filtergraph syntax'' section of the
  1290. ffmpeg-filters manual.
  1291. Input link labels must refer to input streams using the
  1292. @code{[file_index:stream_specifier]} syntax (i.e. the same as @option{-map}
  1293. uses). If @var{stream_specifier} matches multiple streams, the first one will be
  1294. used. An unlabeled input will be connected to the first unused input stream of
  1295. the matching type.
  1296. Output link labels are referred to with @option{-map}. Unlabeled outputs are
  1297. added to the first output file.
  1298. Note that with this option it is possible to use only lavfi sources without
  1299. normal input files.
  1300. For example, to overlay an image over video
  1301. @example
  1302. ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
  1303. '[out]' out.mkv
  1304. @end example
  1305. Here @code{[0:v]} refers to the first video stream in the first input file,
  1306. which is linked to the first (main) input of the overlay filter. Similarly the
  1307. first video stream in the second input is linked to the second (overlay) input
  1308. of overlay.
  1309. Assuming there is only one video stream in each input file, we can omit input
  1310. labels, so the above is equivalent to
  1311. @example
  1312. ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map
  1313. '[out]' out.mkv
  1314. @end example
  1315. Furthermore we can omit the output label and the single output from the filter
  1316. graph will be added to the output file automatically, so we can simply write
  1317. @example
  1318. ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv
  1319. @end example
  1320. To generate 5 seconds of pure red video using lavfi @code{color} source:
  1321. @example
  1322. ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv
  1323. @end example
  1324. @item -filter_complex_threads @var{nb_threads} (@emph{global})
  1325. Defines how many threads are used to process a filter_complex graph.
  1326. Similar to filter_threads but used for @code{-filter_complex} graphs only.
  1327. The default is the number of available CPUs.
  1328. @item -lavfi @var{filtergraph} (@emph{global})
  1329. Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
  1330. outputs. Equivalent to @option{-filter_complex}.
  1331. @item -filter_complex_script @var{filename} (@emph{global})
  1332. This option is similar to @option{-filter_complex}, the only difference is that
  1333. its argument is the name of the file from which a complex filtergraph
  1334. description is to be read.
  1335. @item -accurate_seek (@emph{input})
  1336. This option enables or disables accurate seeking in input files with the
  1337. @option{-ss} option. It is enabled by default, so seeking is accurate when
  1338. transcoding. Use @option{-noaccurate_seek} to disable it, which may be useful
  1339. e.g. when copying some streams and transcoding the others.
  1340. @item -seek_timestamp (@emph{input})
  1341. This option enables or disables seeking by timestamp in input files with the
  1342. @option{-ss} option. It is disabled by default. If enabled, the argument
  1343. to the @option{-ss} option is considered an actual timestamp, and is not
  1344. offset by the start time of the file. This matters only for files which do
  1345. not start from timestamp 0, such as transport streams.
  1346. @item -thread_queue_size @var{size} (@emph{input})
  1347. This option sets the maximum number of queued packets when reading from the
  1348. file or device. With low latency / high rate live streams, packets may be
  1349. discarded if they are not read in a timely manner; raising this value can
  1350. avoid it.
  1351. @item -sdp_file @var{file} (@emph{global})
  1352. Print sdp information for an output stream to @var{file}.
  1353. This allows dumping sdp information when at least one output isn't an
  1354. rtp stream. (Requires at least one of the output formats to be rtp).
  1355. @item -discard (@emph{input})
  1356. Allows discarding specific streams or frames from streams.
  1357. Any input stream can be fully discarded, using value @code{all} whereas
  1358. selective discarding of frames from a stream occurs at the demuxer
  1359. and is not supported by all demuxers.
  1360. @table @option
  1361. @item none
  1362. Discard no frame.
  1363. @item default
  1364. Default, which discards no frames.
  1365. @item noref
  1366. Discard all non-reference frames.
  1367. @item bidir
  1368. Discard all bidirectional frames.
  1369. @item nokey
  1370. Discard all frames excepts keyframes.
  1371. @item all
  1372. Discard all frames.
  1373. @end table
  1374. @item -abort_on @var{flags} (@emph{global})
  1375. Stop and abort on various conditions. The following flags are available:
  1376. @table @option
  1377. @item empty_output
  1378. No packets were passed to the muxer, the output is empty.
  1379. @item empty_output_stream
  1380. No packets were passed to the muxer in some of the output streams.
  1381. @end table
  1382. @item -xerror (@emph{global})
  1383. Stop and exit on error
  1384. @item -max_muxing_queue_size @var{packets} (@emph{output,per-stream})
  1385. When transcoding audio and/or video streams, ffmpeg will not begin writing into
  1386. the output until it has one packet for each such stream. While waiting for that
  1387. to happen, packets for other streams are buffered. This option sets the size of
  1388. this buffer, in packets, for the matching output stream.
  1389. The default value of this option should be high enough for most uses, so only
  1390. touch this option if you are sure that you need it.
  1391. @end table
  1392. As a special exception, you can use a bitmap subtitle stream as input: it
  1393. will be converted into a video with the same size as the largest video in
  1394. the file, or 720x576 if no video is present. Note that this is an
  1395. experimental and temporary solution. It will be removed once libavfilter has
  1396. proper support for subtitles.
  1397. For example, to hardcode subtitles on top of a DVB-T recording stored in
  1398. MPEG-TS format, delaying the subtitles by 1 second:
  1399. @example
  1400. ffmpeg -i input.ts -filter_complex \
  1401. '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
  1402. -sn -map '#0x2dc' output.mkv
  1403. @end example
  1404. (0x2d0, 0x2dc and 0x2ef are the MPEG-TS PIDs of respectively the video,
  1405. audio and subtitles streams; 0:0, 0:3 and 0:7 would have worked too)
  1406. @section Preset files
  1407. A preset file contains a sequence of @var{option}=@var{value} pairs,
  1408. one for each line, specifying a sequence of options which would be
  1409. awkward to specify on the command line. Lines starting with the hash
  1410. ('#') character are ignored and are used to provide comments. Check
  1411. the @file{presets} directory in the FFmpeg source tree for examples.
  1412. There are two types of preset files: ffpreset and avpreset files.
  1413. @subsection ffpreset files
  1414. ffpreset files are specified with the @code{vpre}, @code{apre},
  1415. @code{spre}, and @code{fpre} options. The @code{fpre} option takes the
  1416. filename of the preset instead of a preset name as input and can be
  1417. used for any kind of codec. For the @code{vpre}, @code{apre}, and
  1418. @code{spre} options, the options specified in a preset file are
  1419. applied to the currently selected codec of the same type as the preset
  1420. option.
  1421. The argument passed to the @code{vpre}, @code{apre}, and @code{spre}
  1422. preset options identifies the preset file to use according to the
  1423. following rules:
  1424. First ffmpeg searches for a file named @var{arg}.ffpreset in the
  1425. directories @file{$FFMPEG_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
  1426. the datadir defined at configuration time (usually @file{PREFIX/share/ffmpeg})
  1427. or in a @file{ffpresets} folder along the executable on win32,
  1428. in that order. For example, if the argument is @code{libvpx-1080p}, it will
  1429. search for the file @file{libvpx-1080p.ffpreset}.
  1430. If no such file is found, then ffmpeg will search for a file named
  1431. @var{codec_name}-@var{arg}.ffpreset in the above-mentioned
  1432. directories, where @var{codec_name} is the name of the codec to which
  1433. the preset file options will be applied. For example, if you select
  1434. the video codec with @code{-vcodec libvpx} and use @code{-vpre 1080p},
  1435. then it will search for the file @file{libvpx-1080p.ffpreset}.
  1436. @subsection avpreset files
  1437. avpreset files are specified with the @code{pre} option. They work similar to
  1438. ffpreset files, but they only allow encoder- specific options. Therefore, an
  1439. @var{option}=@var{value} pair specifying an encoder cannot be used.
  1440. When the @code{pre} option is specified, ffmpeg will look for files with the
  1441. suffix .avpreset in the directories @file{$AVCONV_DATADIR} (if set), and
  1442. @file{$HOME/.avconv}, and in the datadir defined at configuration time (usually
  1443. @file{PREFIX/share/ffmpeg}), in that order.
  1444. First ffmpeg searches for a file named @var{codec_name}-@var{arg}.avpreset in
  1445. the above-mentioned directories, where @var{codec_name} is the name of the codec
  1446. to which the preset file options will be applied. For example, if you select the
  1447. video codec with @code{-vcodec libvpx} and use @code{-pre 1080p}, then it will
  1448. search for the file @file{libvpx-1080p.avpreset}.
  1449. If no such file is found, then ffmpeg will search for a file named
  1450. @var{arg}.avpreset in the same directories.
  1451. @c man end OPTIONS
  1452. @chapter Examples
  1453. @c man begin EXAMPLES
  1454. @section Video and Audio grabbing
  1455. If you specify the input format and device then ffmpeg can grab video
  1456. and audio directly.
  1457. @example
  1458. ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
  1459. @end example
  1460. Or with an ALSA audio source (mono input, card id 1) instead of OSS:
  1461. @example
  1462. ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg
  1463. @end example
  1464. Note that you must activate the right video source and channel before
  1465. launching ffmpeg with any TV viewer such as
  1466. @uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also
  1467. have to set the audio recording levels correctly with a
  1468. standard mixer.
  1469. @section X11 grabbing
  1470. Grab the X11 display with ffmpeg via
  1471. @example
  1472. ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0 /tmp/out.mpg
  1473. @end example
  1474. 0.0 is display.screen number of your X11 server, same as
  1475. the DISPLAY environment variable.
  1476. @example
  1477. ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0+10,20 /tmp/out.mpg
  1478. @end example
  1479. 0.0 is display.screen number of your X11 server, same as the DISPLAY environment
  1480. variable. 10 is the x-offset and 20 the y-offset for the grabbing.
  1481. @section Video and Audio file format conversion
  1482. Any supported file format and protocol can serve as input to ffmpeg:
  1483. Examples:
  1484. @itemize
  1485. @item
  1486. You can use YUV files as input:
  1487. @example
  1488. ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
  1489. @end example
  1490. It will use the files:
  1491. @example
  1492. /tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
  1493. /tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
  1494. @end example
  1495. The Y files use twice the resolution of the U and V files. They are
  1496. raw files, without header. They can be generated by all decent video
  1497. decoders. You must specify the size of the image with the @option{-s} option
  1498. if ffmpeg cannot guess it.
  1499. @item
  1500. You can input from a raw YUV420P file:
  1501. @example
  1502. ffmpeg -i /tmp/test.yuv /tmp/out.avi
  1503. @end example
  1504. test.yuv is a file containing raw YUV planar data. Each frame is composed
  1505. of the Y plane followed by the U and V planes at half vertical and
  1506. horizontal resolution.
  1507. @item
  1508. You can output to a raw YUV420P file:
  1509. @example
  1510. ffmpeg -i mydivx.avi hugefile.yuv
  1511. @end example
  1512. @item
  1513. You can set several input files and output files:
  1514. @example
  1515. ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
  1516. @end example
  1517. Converts the audio file a.wav and the raw YUV video file a.yuv
  1518. to MPEG file a.mpg.
  1519. @item
  1520. You can also do audio and video conversions at the same time:
  1521. @example
  1522. ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
  1523. @end example
  1524. Converts a.wav to MPEG audio at 22050 Hz sample rate.
  1525. @item
  1526. You can encode to several formats at the same time and define a
  1527. mapping from input stream to output streams:
  1528. @example
  1529. ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2
  1530. @end example
  1531. Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
  1532. file:index' specifies which input stream is used for each output
  1533. stream, in the order of the definition of output streams.
  1534. @item
  1535. You can transcode decrypted VOBs:
  1536. @example
  1537. 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
  1538. @end example
  1539. This is a typical DVD ripping example; the input is a VOB file, the
  1540. output an AVI file with MPEG-4 video and MP3 audio. Note that in this
  1541. command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
  1542. GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
  1543. input video. Furthermore, the audio stream is MP3-encoded so you need
  1544. to enable LAME support by passing @code{--enable-libmp3lame} to configure.
  1545. The mapping is particularly useful for DVD transcoding
  1546. to get the desired audio language.
  1547. NOTE: To see the supported input formats, use @code{ffmpeg -demuxers}.
  1548. @item
  1549. You can extract images from a video, or create a video from many images:
  1550. For extracting images from a video:
  1551. @example
  1552. ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
  1553. @end example
  1554. This will extract one video frame per second from the video and will
  1555. output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg},
  1556. etc. Images will be rescaled to fit the new WxH values.
  1557. If you want to extract just a limited number of frames, you can use the
  1558. above command in combination with the @code{-frames:v} or @code{-t} option,
  1559. or in combination with -ss to start extracting from a certain point in time.
  1560. For creating a video from many images:
  1561. @example
  1562. ffmpeg -f image2 -framerate 12 -i foo-%03d.jpeg -s WxH foo.avi
  1563. @end example
  1564. The syntax @code{foo-%03d.jpeg} specifies to use a decimal number
  1565. composed of three digits padded with zeroes to express the sequence
  1566. number. It is the same syntax supported by the C printf function, but
  1567. only formats accepting a normal integer are suitable.
  1568. When importing an image sequence, -i also supports expanding
  1569. shell-like wildcard patterns (globbing) internally, by selecting the
  1570. image2-specific @code{-pattern_type glob} option.
  1571. For example, for creating a video from filenames matching the glob pattern
  1572. @code{foo-*.jpeg}:
  1573. @example
  1574. ffmpeg -f image2 -pattern_type glob -framerate 12 -i 'foo-*.jpeg' -s WxH foo.avi
  1575. @end example
  1576. @item
  1577. You can put many streams of the same type in the output:
  1578. @example
  1579. ffmpeg -i test1.avi -i test2.avi -map 1:1 -map 1:0 -map 0:1 -map 0:0 -c copy -y test12.nut
  1580. @end example
  1581. The resulting output file @file{test12.nut} will contain the first four streams
  1582. from the input files in reverse order.
  1583. @item
  1584. To force CBR video output:
  1585. @example
  1586. ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
  1587. @end example
  1588. @item
  1589. The four options lmin, lmax, mblmin and mblmax use 'lambda' units,
  1590. but you may use the QP2LAMBDA constant to easily convert from 'q' units:
  1591. @example
  1592. ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
  1593. @end example
  1594. @end itemize
  1595. @c man end EXAMPLES
  1596. @include config.texi
  1597. @ifset config-all
  1598. @ifset config-avutil
  1599. @include utils.texi
  1600. @end ifset
  1601. @ifset config-avcodec
  1602. @include codecs.texi
  1603. @include bitstream_filters.texi
  1604. @end ifset
  1605. @ifset config-avformat
  1606. @include formats.texi
  1607. @include protocols.texi
  1608. @end ifset
  1609. @ifset config-avdevice
  1610. @include devices.texi
  1611. @end ifset
  1612. @ifset config-swresample
  1613. @include resampler.texi
  1614. @end ifset
  1615. @ifset config-swscale
  1616. @include scaler.texi
  1617. @end ifset
  1618. @ifset config-avfilter
  1619. @include filters.texi
  1620. @end ifset
  1621. @end ifset
  1622. @chapter See Also
  1623. @ifhtml
  1624. @ifset config-all
  1625. @url{ffmpeg.html,ffmpeg}
  1626. @end ifset
  1627. @ifset config-not-all
  1628. @url{ffmpeg-all.html,ffmpeg-all},
  1629. @end ifset
  1630. @url{ffplay.html,ffplay}, @url{ffprobe.html,ffprobe},
  1631. @url{ffmpeg-utils.html,ffmpeg-utils},
  1632. @url{ffmpeg-scaler.html,ffmpeg-scaler},
  1633. @url{ffmpeg-resampler.html,ffmpeg-resampler},
  1634. @url{ffmpeg-codecs.html,ffmpeg-codecs},
  1635. @url{ffmpeg-bitstream-filters.html,ffmpeg-bitstream-filters},
  1636. @url{ffmpeg-formats.html,ffmpeg-formats},
  1637. @url{ffmpeg-devices.html,ffmpeg-devices},
  1638. @url{ffmpeg-protocols.html,ffmpeg-protocols},
  1639. @url{ffmpeg-filters.html,ffmpeg-filters}
  1640. @end ifhtml
  1641. @ifnothtml
  1642. @ifset config-all
  1643. ffmpeg(1),
  1644. @end ifset
  1645. @ifset config-not-all
  1646. ffmpeg-all(1),
  1647. @end ifset
  1648. ffplay(1), ffprobe(1),
  1649. ffmpeg-utils(1), ffmpeg-scaler(1), ffmpeg-resampler(1),
  1650. ffmpeg-codecs(1), ffmpeg-bitstream-filters(1), ffmpeg-formats(1),
  1651. ffmpeg-devices(1), ffmpeg-protocols(1), ffmpeg-filters(1)
  1652. @end ifnothtml
  1653. @include authors.texi
  1654. @ignore
  1655. @setfilename ffmpeg
  1656. @settitle ffmpeg video converter
  1657. @end ignore
  1658. @bye