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1\input texinfo @c -*- texinfo -*-
2@documentencoding UTF-8
3
4@settitle ffmpeg Documentation
5@titlepage
6@center @titlefont{ffmpeg Documentation}
7@end titlepage
8
9@top
10
11@contents
12
13@chapter Synopsis
14
15ffmpeg [@var{global_options}] @{[@var{input_file_options}] -i @file{input_url}@} ... @{[@var{output_file_options}] @file{output_url}@} ...
16
17@chapter Description
18@c man begin DESCRIPTION
19
20@command{ffmpeg} is a very fast video and audio converter that can also grab from
21a live audio/video source. It can also convert between arbitrary sample
22rates and resize video on the fly with a high quality polyphase filter.
23
24@command{ffmpeg} reads from an arbitrary number of input "files" (which can be regular
25files, pipes, network streams, grabbing devices, etc.), specified by the
26@code{-i} option, and writes to an arbitrary number of output "files", which are
27specified by a plain output url. Anything found on the command line which
28cannot be interpreted as an option is considered to be an output url.
29
30Each input or output url can, in principle, contain any number of streams of
31different types (video/audio/subtitle/attachment/data). The allowed number and/or
32types of streams may be limited by the container format. Selecting which
33streams from which inputs will go into which output is either done automatically
34or with the @code{-map} option (see the Stream selection chapter).
35
36To refer to input files in options, you must use their indices (0-based). E.g.
37the first input file is @code{0}, the second is @code{1}, etc. Similarly, streams
38within a file are referred to by their indices. E.g. @code{2:3} refers to the
39fourth stream in the third input file. Also see the Stream specifiers chapter.
40
41As a general rule, options are applied to the next specified
42file. Therefore, order is important, and you can have the same
43option on the command line multiple times. Each occurrence is
44then applied to the next input or output file.
45Exceptions from this rule are the global options (e.g. verbosity level),
46which should be specified first.
47
48Do not mix input and output files -- first specify all input files, then all
49output files. Also do not mix options which belong to different files. All
50options apply ONLY to the next input or output file and are reset between files.
51
52@itemize
53@item
54To set the video bitrate of the output file to 64 kbit/s:
55@example
56ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi
57@end example
58
59@item
60To force the frame rate of the output file to 24 fps:
61@example
62ffmpeg -i input.avi -r 24 output.avi
63@end example
64
65@item
66To force the frame rate of the input file (valid for raw formats only)
67to 1 fps and the frame rate of the output file to 24 fps:
68@example
69ffmpeg -r 1 -i input.m2v -r 24 output.avi
70@end example
71@end itemize
72
73The format option may be needed for raw input files.
74
75@c man end DESCRIPTION
76
77@chapter Detailed description
78@c man begin DETAILED DESCRIPTION
79
80The transcoding process in @command{ffmpeg} for each output can be described by
81the following diagram:
82
83@verbatim
84 _______              ______________
85|       |            |              |
86| input |  demuxer   | encoded data |   decoder
87| file  | ---------> | packets      | -----+
88|_______|            |______________|      |
89                                           v
90                                       _________
91                                      |         |
92                                      | decoded |
93                                      | frames  |
94                                      |_________|
95 ________             ______________       |
96|        |           |              |      |
97| output | <-------- | encoded data | <----+
98| file   |   muxer   | packets      |   encoder
99|________|           |______________|
100
101
102@end verbatim
103
104@command{ffmpeg} calls the libavformat library (containing demuxers) to read
105input files and get packets containing encoded data from them. When there are
106multiple input files, @command{ffmpeg} tries to keep them synchronized by
107tracking lowest timestamp on any active input stream.
108
109Encoded packets are then passed to the decoder (unless streamcopy is selected
110for the stream, see further for a description). The decoder produces
111uncompressed frames (raw video/PCM audio/...) which can be processed further by
112filtering (see next section). After filtering, the frames are passed to the
113encoder, which encodes them and outputs encoded packets. Finally those are
114passed to the muxer, which writes the encoded packets to the output file.
115
116@section Filtering
117Before encoding, @command{ffmpeg} can process raw audio and video frames using
118filters from the libavfilter library. Several chained filters form a filter
119graph. @command{ffmpeg} distinguishes between two types of filtergraphs:
120simple and complex.
121
122@subsection Simple filtergraphs
123Simple filtergraphs are those that have exactly one input and output, both of
124the same type. In the above diagram they can be represented by simply inserting
125an additional step between decoding and encoding:
126
127@verbatim
128 _________                        ______________
129|         |                      |              |
130| decoded |                      | encoded data |
131| frames  |\                   _ | packets      |
132|_________| \                  /||______________|
133             \   __________   /
134  simple     _\||          | /  encoder
135  filtergraph   | filtered |/
136                | frames   |
137                |__________|
138
139@end verbatim
140
141Simple filtergraphs are configured with the per-stream @option{-filter} option
142(with @option{-vf} and @option{-af} aliases for video and audio respectively).
143A simple filtergraph for video can look for example like this:
144
145@verbatim
146 _______        _____________        _______        ________
147|       |      |             |      |       |      |        |
148| input | ---> | deinterlace | ---> | scale | ---> | output |
149|_______|      |_____________|      |_______|      |________|
150
151@end verbatim
152
153Note that some filters change frame properties but not frame contents. E.g. the
154@code{fps} filter in the example above changes number of frames, but does not
155touch the frame contents. Another example is the @code{setpts} filter, which
156only sets timestamps and otherwise passes the frames unchanged.
157
158@subsection Complex filtergraphs
159Complex filtergraphs are those which cannot be described as simply a linear
160processing chain applied to one stream. This is the case, for example, when the graph has
161more than one input and/or output, or when output stream type is different from
162input. They can be represented with the following diagram:
163
164@verbatim
165 _________
166|         |
167| input 0 |\                    __________
168|_________| \                  |          |
169             \   _________    /| output 0 |
170              \ |         |  / |__________|
171 _________     \| complex | /
172|         |     |         |/
173| input 1 |---->| filter  |\
174|_________|     |         | \   __________
175               /| graph   |  \ |          |
176              / |         |   \| output 1 |
177 _________   /  |_________|    |__________|
178|         | /
179| input 2 |/
180|_________|
181
182@end verbatim
183
184Complex filtergraphs are configured with the @option{-filter_complex} option.
185Note that this option is global, since a complex filtergraph, by its nature,
186cannot be unambiguously associated with a single stream or file.
187
188The @option{-lavfi} option is equivalent to @option{-filter_complex}.
189
190A trivial example of a complex filtergraph is the @code{overlay} filter, which
191has two video inputs and one video output, containing one video overlaid on top
192of the other. Its audio counterpart is the @code{amix} filter.
193
194@section Stream copy
195Stream copy is a mode selected by supplying the @code{copy} parameter to the
196@option{-codec} option. It makes @command{ffmpeg} omit the decoding and encoding
197step for the specified stream, so it does only demuxing and muxing. It is useful
198for changing the container format or modifying container-level metadata. The
199diagram above will, in this case, simplify to this:
200
201@verbatim
202 _______              ______________            ________
203|       |            |              |          |        |
204| input |  demuxer   | encoded data |  muxer   | output |
205| file  | ---------> | packets      | -------> | file   |
206|_______|            |______________|          |________|
207
208@end verbatim
209
210Since there is no decoding or encoding, it is very fast and there is no quality
211loss. However, it might not work in some cases because of many factors. Applying
212filters is obviously also impossible, since filters work on uncompressed data.
213
214@c man end DETAILED DESCRIPTION
215
216@chapter Stream selection
217@c man begin STREAM SELECTION
218
219@command{ffmpeg} provides the @code{-map} option for manual control of stream selection in each
220output file. Users can skip @code{-map} and let ffmpeg perform automatic stream selection as
221described below. The @code{-vn / -an / -sn / -dn} options can be used to skip inclusion of
222video, audio, subtitle and data streams respectively, whether manually mapped or automatically
223selected, except for those streams which are outputs of complex filtergraphs.
224
225@section Description
226The sub-sections that follow describe the various rules that are involved in stream selection.
227The examples that follow next show how these rules are applied in practice.
228
229While every effort is made to accurately reflect the behavior of the program, FFmpeg is under
230continuous development and the code may have changed since the time of this writing.
231
232@subsection Automatic stream selection
233
234In the absence of any map options for a particular output file, ffmpeg inspects the output
235format to check which type of streams can be included in it, viz. video, audio and/or
236subtitles. For each acceptable stream type, ffmpeg will pick one stream, when available,
237from among all the inputs.
238
239It will select that stream based upon the following criteria:
240@itemize
241@item
242for video, it is the stream with the highest resolution,
243@item
244for audio, it is the stream with the most channels,
245@item
246for subtitles, it is the first subtitle stream found but there's a caveat.
247The output format's default subtitle encoder can be either text-based or image-based,
248and only a subtitle stream of the same type will be chosen.
249@end itemize
250
251In the case where several streams of the same type rate equally, the stream with the lowest
252index is chosen.
253
254Data or attachment streams are not automatically selected and can only be included
255using @code{-map}.
256@subsection Manual stream selection
257
258When @code{-map} is used, only user-mapped streams are included in that output file,
259with one possible exception for filtergraph outputs described below.
260
261@subsection Complex filtergraphs
262
263If there are any complex filtergraph output streams with unlabeled pads, they will be added
264to the first output file. This will lead to a fatal error if the stream type is not supported
265by the output format. In the absence of the map option, the inclusion of these streams leads
266to the automatic stream selection of their types being skipped. If map options are present,
267these filtergraph streams are included in addition to the mapped streams.
268
269Complex filtergraph output streams with labeled pads must be mapped once and exactly once.
270
271@subsection Stream handling
272
273Stream handling is independent of stream selection, with an exception for subtitles described
274below. Stream handling is set via the @code{-codec} option addressed to streams within a
275specific @emph{output} file. In particular, codec options are applied by ffmpeg after the
276stream selection process and thus do not influence the latter. If no @code{-codec} option is
277specified for a stream type, ffmpeg will select the default encoder registered by the output
278file muxer.
279
280An exception exists for subtitles. If a subtitle encoder is specified for an output file, the
281first subtitle stream found of any type, text or image, will be included. ffmpeg does not validate
282if the specified encoder can convert the selected stream or if the converted stream is acceptable
283within the output format. This applies generally as well: when the user sets an encoder manually,
284the stream selection process cannot check if the encoded stream can be muxed into the output file.
285If it cannot, ffmpeg will abort and @emph{all} output files will fail to be processed.
286
287@section Examples
288
289The following examples illustrate the behavior, quirks and limitations of ffmpeg's stream
290selection methods.
291
292They assume the following three input files.
293
294@verbatim
295
296input file 'A.avi'
297      stream 0: video 640x360
298      stream 1: audio 2 channels
299
300input file 'B.mp4'
301      stream 0: video 1920x1080
302      stream 1: audio 2 channels
303      stream 2: subtitles (text)
304      stream 3: audio 5.1 channels
305      stream 4: subtitles (text)
306
307input file 'C.mkv'
308      stream 0: video 1280x720
309      stream 1: audio 2 channels
310      stream 2: subtitles (image)
311@end verbatim
312
313@subsubheading Example: automatic stream selection
314@example
315ffmpeg -i A.avi -i B.mp4 out1.mkv out2.wav -map 1:a -c:a copy out3.mov
316@end example
317There are three output files specified, and for the first two, no @code{-map} options
318are set, so ffmpeg will select streams for these two files automatically.
319
320@file{out1.mkv} is a Matroska container file and accepts video, audio and subtitle streams,
321so ffmpeg will try to select one of each type.@*
322For video, it will select @code{stream 0} from @file{B.mp4}, which has the highest
323resolution among all the input video streams.@*
324For audio, it will select @code{stream 3} from @file{B.mp4}, since it has the greatest
325number of channels.@*
326For subtitles, it will select @code{stream 2} from @file{B.mp4}, which is the first subtitle
327stream from among @file{A.avi} and @file{B.mp4}.
328
329@file{out2.wav} accepts only audio streams, so only @code{stream 3} from @file{B.mp4} is
330selected.
331
332For @file{out3.mov}, since a @code{-map} option is set, no automatic stream selection will
333occur. The @code{-map 1:a} option will select all audio streams from the second input
334@file{B.mp4}. No other streams will be included in this output file.
335
336For the first two outputs, all included streams will be transcoded. The encoders chosen will
337be the default ones registered by each output format, which may not match the codec of the
338selected input streams.
339
340For the third output, codec option for audio streams has been set
341to @code{copy}, so no decoding-filtering-encoding operations will occur, or @emph{can} occur.
342Packets of selected streams shall be conveyed from the input file and muxed within the output
343file.
344
345@subsubheading Example: automatic subtitles selection
346@example
347ffmpeg -i C.mkv out1.mkv -c:s dvdsub -an out2.mkv
348@end example
349Although @file{out1.mkv} is a Matroska container file which accepts subtitle streams, only a
350video and audio stream shall be selected. The subtitle stream of @file{C.mkv} is image-based
351and the default subtitle encoder of the Matroska muxer is text-based, so a transcode operation
352for the subtitles is expected to fail and hence the stream isn't selected. However, in
353@file{out2.mkv}, a subtitle encoder is specified in the command and so, the subtitle stream is
354selected, in addition to the video stream. The presence of @code{-an} disables audio stream
355selection for @file{out2.mkv}.
356
357@subsubheading Example: unlabeled filtergraph outputs
358@example
359ffmpeg -i A.avi -i C.mkv -i B.mp4 -filter_complex "overlay" out1.mp4 out2.srt
360@end example
361A filtergraph is setup here using the @code{-filter_complex} option and consists of a single
362video filter. The @code{overlay} filter requires exactly two video inputs, but none are
363specified, so the first two available video streams are used, those of @file{A.avi} and
364@file{C.mkv}. The output pad of the filter has no label and so is sent to the first output file
365@file{out1.mp4}. Due to this, automatic selection of the video stream is skipped, which would
366have selected the stream in @file{B.mp4}. The audio stream with most channels viz. @code{stream 3}
367in @file{B.mp4}, is chosen automatically. No subtitle stream is chosen however, since the MP4
368format has no default subtitle encoder registered, and the user hasn't specified a subtitle encoder.
369
370The 2nd output file, @file{out2.srt}, only accepts text-based subtitle streams. So, even though
371the first subtitle stream available belongs to @file{C.mkv}, it is image-based and hence skipped.
372The selected stream, @code{stream 2} in @file{B.mp4}, is the first text-based subtitle stream.
373
374@subsubheading Example: labeled filtergraph outputs
375@example
376ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0[outv];overlay;aresample" \
377       -map '[outv]' -an        out1.mp4 \
378                                out2.mkv \
379       -map '[outv]' -map 1:a:0 out3.mkv
380@end example
381
382The above command will fail, as the output pad labelled @code{[outv]} has been mapped twice.
383None of the output files shall be processed.
384
385@example
386ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0[outv];overlay;aresample" \
387       -an        out1.mp4 \
388                  out2.mkv \
389       -map 1:a:0 out3.mkv
390@end example
391
392This command above will also fail as the hue filter output has a label, @code{[outv]},
393and hasn't been mapped anywhere.
394
395The command should be modified as follows,
396@example
397ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0,split=2[outv1][outv2];overlay;aresample" \
398        -map '[outv1]' -an        out1.mp4 \
399                                  out2.mkv \
400        -map '[outv2]' -map 1:a:0 out3.mkv
401@end example
402The video stream from @file{B.mp4} is sent to the hue filter, whose output is cloned once using
403the split filter, and both outputs labelled. Then a copy each is mapped to the first and third
404output files.
405
406The overlay filter, requiring two video inputs, uses the first two unused video streams. Those
407are the streams from @file{A.avi} and @file{C.mkv}. The overlay output isn't labelled, so it is
408sent to the first output file @file{out1.mp4}, regardless of the presence of the @code{-map} option.
409
410The aresample filter is sent the first unused audio stream, that of @file{A.avi}. Since this filter
411output is also unlabelled, it too is mapped to the first output file. The presence of @code{-an}
412only suppresses automatic or manual stream selection of audio streams, not outputs sent from
413filtergraphs. Both these mapped streams shall be ordered before the mapped stream in @file{out1.mp4}.
414
415The video, audio and subtitle streams mapped to @code{out2.mkv} are entirely determined by
416automatic stream selection.
417
418@file{out3.mkv} consists of the cloned video output from the hue filter and the first audio
419stream from @file{B.mp4}.
420@*
421
422@c man end STREAM SELECTION
423
424@chapter Options
425@c man begin OPTIONS
426
427@include fftools-common-opts.texi
428
429@section Main options
430
431@table @option
432
433@item -f @var{fmt} (@emph{input/output})
434Force input or output file format. The format is normally auto detected for input
435files and guessed from the file extension for output files, so this option is not
436needed in most cases.
437
438@item -i @var{url} (@emph{input})
439input file url
440
441@item -y (@emph{global})
442Overwrite output files without asking.
443
444@item -n (@emph{global})
445Do not overwrite output files, and exit immediately if a specified
446output file already exists.
447
448@item -stream_loop @var{number} (@emph{input})
449Set number of times input stream shall be looped. Loop 0 means no loop,
450loop -1 means infinite loop.
451
452@item -c[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
453@itemx -codec[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
454Select an encoder (when used before an output file) or a decoder (when used
455before an input file) for one or more streams. @var{codec} is the name of a
456decoder/encoder or a special value @code{copy} (output only) to indicate that
457the stream is not to be re-encoded.
458
459For example
460@example
461ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT
462@end example
463encodes all video streams with libx264 and copies all audio streams.
464
465For each stream, the last matching @code{c} option is applied, so
466@example
467ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT
468@end example
469will copy all the streams except the second video, which will be encoded with
470libx264, and the 138th audio, which will be encoded with libvorbis.
471
472@item -t @var{duration} (@emph{input/output})
473When used as an input option (before @code{-i}), limit the @var{duration} of
474data read from the input file.
475
476When used as an output option (before an output url), stop writing the
477output after its duration reaches @var{duration}.
478
479@var{duration} must be a time duration specification,
480see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
481
482-to and -t are mutually exclusive and -t has priority.
483
484@item -to @var{position} (@emph{input/output})
485Stop writing the output or reading the input at @var{position}.
486@var{position} must be a time duration specification,
487see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
488
489-to and -t are mutually exclusive and -t has priority.
490
491@item -fs @var{limit_size} (@emph{output})
492Set the file size limit, expressed in bytes. No further chunk of bytes is written
493after the limit is exceeded. The size of the output file is slightly more than the
494requested file size.
495
496@item -ss @var{position} (@emph{input/output})
497When used as an input option (before @code{-i}), seeks in this input file to
498@var{position}. Note that in most formats it is not possible to seek exactly,
499so @command{ffmpeg} will seek to the closest seek point before @var{position}.
500When transcoding and @option{-accurate_seek} is enabled (the default), this
501extra segment between the seek point and @var{position} will be decoded and
502discarded. When doing stream copy or when @option{-noaccurate_seek} is used, it
503will be preserved.
504
505When used as an output option (before an output url), decodes but discards
506input until the timestamps reach @var{position}.
507
508@var{position} must be a time duration specification,
509see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
510
511@item -sseof @var{position} (@emph{input})
512
513Like the @code{-ss} option but relative to the "end of file". That is negative
514values are earlier in the file, 0 is at EOF.
515
516@item -itsoffset @var{offset} (@emph{input})
517Set the input time offset.
518
519@var{offset} must be a time duration specification,
520see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
521
522The offset is added to the timestamps of the input files. Specifying
523a positive offset means that the corresponding streams are delayed by
524the time duration specified in @var{offset}.
525
526@item -itsscale @var{scale} (@emph{input,per-stream})
527Rescale input timestamps. @var{scale} should be a floating point number.
528
529@item -timestamp @var{date} (@emph{output})
530Set the recording timestamp in the container.
531
532@var{date} must be a date specification,
533see @ref{date syntax,,the Date section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
534
535@item -metadata[:metadata_specifier] @var{key}=@var{value} (@emph{output,per-metadata})
536Set a metadata key/value pair.
537
538An optional @var{metadata_specifier} may be given to set metadata
539on streams, chapters or programs. See @code{-map_metadata}
540documentation for details.
541
542This option overrides metadata set with @code{-map_metadata}. It is
543also possible to delete metadata by using an empty value.
544
545For example, for setting the title in the output file:
546@example
547ffmpeg -i in.avi -metadata title="my title" out.flv
548@end example
549
550To set the language of the first audio stream:
551@example
552ffmpeg -i INPUT -metadata:s:a:0 language=eng OUTPUT
553@end example
554
555@item -disposition[:stream_specifier] @var{value} (@emph{output,per-stream})
556Sets the disposition for a stream.
557
558This option overrides the disposition copied from the input stream. It is also
559possible to delete the disposition by setting it to 0.
560
561The following dispositions are recognized:
562@table @option
563@item default
564@item dub
565@item original
566@item comment
567@item lyrics
568@item karaoke
569@item forced
570@item hearing_impaired
571@item visual_impaired
572@item clean_effects
573@item attached_pic
574@item captions
575@item descriptions
576@item dependent
577@item metadata
578@end table
579
580For example, to make the second audio stream the default stream:
581@example
582ffmpeg -i in.mkv -c copy -disposition:a:1 default out.mkv
583@end example
584
585To make the second subtitle stream the default stream and remove the default
586disposition from the first subtitle stream:
587@example
588ffmpeg -i in.mkv -c copy -disposition:s:0 0 -disposition:s:1 default out.mkv
589@end example
590
591To add an embedded cover/thumbnail:
592@example
593ffmpeg -i in.mp4 -i IMAGE -map 0 -map 1 -c copy -c:v:1 png -disposition:v:1 attached_pic out.mp4
594@end example
595
596Not all muxers support embedded thumbnails, and those who do, only support a few formats, like JPEG or PNG.
597
598@item -program [title=@var{title}:][program_num=@var{program_num}:]st=@var{stream}[:st=@var{stream}...] (@emph{output})
599
600Creates a program with the specified @var{title}, @var{program_num} and adds the specified
601@var{stream}(s) to it.
602
603@item -target @var{type} (@emph{output})
604Specify target file type (@code{vcd}, @code{svcd}, @code{dvd}, @code{dv},
605@code{dv50}). @var{type} may be prefixed with @code{pal-}, @code{ntsc-} or
606@code{film-} to use the corresponding standard. All the format options
607(bitrate, codecs, buffer sizes) are then set automatically. You can just type:
608
609@example
610ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
611@end example
612
613Nevertheless you can specify additional options as long as you know
614they do not conflict with the standard, as in:
615
616@example
617ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
618@end example
619
620@item -dn (@emph{input/output})
621As an input option, blocks all data streams of a file from being filtered or
622being automatically selected or mapped for any output. See @code{-discard}
623option to disable streams individually.
624
625As an output option, disables data recording i.e. automatic selection or
626mapping of any data stream. For full manual control see the @code{-map}
627option.
628
629@item -dframes @var{number} (@emph{output})
630Set the number of data frames to output. This is an obsolete alias for
631@code{-frames:d}, which you should use instead.
632
633@item -frames[:@var{stream_specifier}] @var{framecount} (@emph{output,per-stream})
634Stop writing to the stream after @var{framecount} frames.
635
636@item -q[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
637@itemx -qscale[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
638Use fixed quality scale (VBR). The meaning of @var{q}/@var{qscale} is
639codec-dependent.
640If @var{qscale} is used without a @var{stream_specifier} then it applies only
641to the video stream, this is to maintain compatibility with previous behavior
642and as specifying the same codec specific value to 2 different codecs that is
643audio and video generally is not what is intended when no stream_specifier is
644used.
645
646@anchor{filter_option}
647@item -filter[:@var{stream_specifier}] @var{filtergraph} (@emph{output,per-stream})
648Create the filtergraph specified by @var{filtergraph} and use it to
649filter the stream.
650
651@var{filtergraph} is a description of the filtergraph to apply to
652the stream, and must have a single input and a single output of the
653same type of the stream. In the filtergraph, the input is associated
654to the label @code{in}, and the output to the label @code{out}. See
655the ffmpeg-filters manual for more information about the filtergraph
656syntax.
657
658See the @ref{filter_complex_option,,-filter_complex option} if you
659want to create filtergraphs with multiple inputs and/or outputs.
660
661@item -filter_script[:@var{stream_specifier}] @var{filename} (@emph{output,per-stream})
662This option is similar to @option{-filter}, the only difference is that its
663argument is the name of the file from which a filtergraph description is to be
664read.
665
666@item -filter_threads @var{nb_threads} (@emph{global})
667Defines how many threads are used to process a filter pipeline. Each pipeline
668will produce a thread pool with this many threads available for parallel processing.
669The default is the number of available CPUs.
670
671@item -pre[:@var{stream_specifier}] @var{preset_name} (@emph{output,per-stream})
672Specify the preset for matching stream(s).
673
674@item -stats (@emph{global})
675Print encoding progress/statistics. It is on by default, to explicitly
676disable it you need to specify @code{-nostats}.
677
678@item -progress @var{url} (@emph{global})
679Send program-friendly progress information to @var{url}.
680
681Progress information is written approximately every second and at the end of
682the encoding process. It is made of "@var{key}=@var{value}" lines. @var{key}
683consists of only alphanumeric characters. The last key of a sequence of
684progress information is always "progress".
685
686@anchor{stdin option}
687@item -stdin
688Enable interaction on standard input. On by default unless standard input is
689used as an input. To explicitly disable interaction you need to specify
690@code{-nostdin}.
691
692Disabling interaction on standard input is useful, for example, if
693ffmpeg is in the background process group. Roughly the same result can
694be achieved with @code{ffmpeg ... < /dev/null} but it requires a
695shell.
696
697@item -debug_ts (@emph{global})
698Print timestamp information. It is off by default. This option is
699mostly useful for testing and debugging purposes, and the output
700format may change from one version to another, so it should not be
701employed by portable scripts.
702
703See also the option @code{-fdebug ts}.
704
705@item -attach @var{filename} (@emph{output})
706Add an attachment to the output file. This is supported by a few formats
707like Matroska for e.g. fonts used in rendering subtitles. Attachments
708are implemented as a specific type of stream, so this option will add
709a new stream to the file. It is then possible to use per-stream options
710on this stream in the usual way. Attachment streams created with this
711option will be created after all the other streams (i.e. those created
712with @code{-map} or automatic mappings).
713
714Note that for Matroska you also have to set the mimetype metadata tag:
715@example
716ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv
717@end example
718(assuming that the attachment stream will be third in the output file).
719
720@item -dump_attachment[:@var{stream_specifier}] @var{filename} (@emph{input,per-stream})
721Extract the matching attachment stream into a file named @var{filename}. If
722@var{filename} is empty, then the value of the @code{filename} metadata tag
723will be used.
724
725E.g. to extract the first attachment to a file named 'out.ttf':
726@example
727ffmpeg -dump_attachment:t:0 out.ttf -i INPUT
728@end example
729To extract all attachments to files determined by the @code{filename} tag:
730@example
731ffmpeg -dump_attachment:t "" -i INPUT
732@end example
733
734Technical note -- attachments are implemented as codec extradata, so this
735option can actually be used to extract extradata from any stream, not just
736attachments.
737
738@item -noautorotate
739Disable automatically rotating video based on file metadata.
740
741@end table
742
743@section Video Options
744
745@table @option
746@item -vframes @var{number} (@emph{output})
747Set the number of video frames to output. This is an obsolete alias for
748@code{-frames:v}, which you should use instead.
749@item -r[:@var{stream_specifier}] @var{fps} (@emph{input/output,per-stream})
750Set frame rate (Hz value, fraction or abbreviation).
751
752As an input option, ignore any timestamps stored in the file and instead
753generate timestamps assuming constant frame rate @var{fps}.
754This is not the same as the @option{-framerate} option used for some input formats
755like image2 or v4l2 (it used to be the same in older versions of FFmpeg).
756If in doubt use @option{-framerate} instead of the input option @option{-r}.
757
758As an output option, duplicate or drop input frames to achieve constant output
759frame rate @var{fps}.
760
761@item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream})
762Set frame size.
763
764As an input option, this is a shortcut for the @option{video_size} private
765option, recognized by some demuxers for which the frame size is either not
766stored in the file or is configurable -- e.g. raw video or video grabbers.
767
768As an output option, this inserts the @code{scale} video filter to the
769@emph{end} of the corresponding filtergraph. Please use the @code{scale} filter
770directly to insert it at the beginning or some other place.
771
772The format is @samp{wxh} (default - same as source).
773
774@item -aspect[:@var{stream_specifier}] @var{aspect} (@emph{output,per-stream})
775Set the video display aspect ratio specified by @var{aspect}.
776
777@var{aspect} can be a floating point number string, or a string of the
778form @var{num}:@var{den}, where @var{num} and @var{den} are the
779numerator and denominator of the aspect ratio. For example "4:3",
780"16:9", "1.3333", and "1.7777" are valid argument values.
781
782If used together with @option{-vcodec copy}, it will affect the aspect ratio
783stored at container level, but not the aspect ratio stored in encoded
784frames, if it exists.
785
786@item -vn (@emph{input/output})
787As an input option, blocks all video streams of a file from being filtered or
788being automatically selected or mapped for any output. See @code{-discard}
789option to disable streams individually.
790
791As an output option, disables video recording i.e. automatic selection or
792mapping of any video stream. For full manual control see the @code{-map}
793option.
794
795@item -vcodec @var{codec} (@emph{output})
796Set the video codec. This is an alias for @code{-codec:v}.
797
798@item -pass[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
799Select the pass number (1 or 2). It is used to do two-pass
800video encoding. The statistics of the video are recorded in the first
801pass into a log file (see also the option -passlogfile),
802and in the second pass that log file is used to generate the video
803at the exact requested bitrate.
804On pass 1, you may just deactivate audio and set output to null,
805examples for Windows and Unix:
806@example
807ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
808ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null
809@end example
810
811@item -passlogfile[:@var{stream_specifier}] @var{prefix} (@emph{output,per-stream})
812Set two-pass log file name prefix to @var{prefix}, the default file name
813prefix is ``ffmpeg2pass''. The complete file name will be
814@file{PREFIX-N.log}, where N is a number specific to the output
815stream
816
817@item -vf @var{filtergraph} (@emph{output})
818Create the filtergraph specified by @var{filtergraph} and use it to
819filter the stream.
820
821This is an alias for @code{-filter:v}, see the @ref{filter_option,,-filter option}.
822@end table
823
824@section Advanced Video options
825
826@table @option
827@item -pix_fmt[:@var{stream_specifier}] @var{format} (@emph{input/output,per-stream})
828Set pixel format. Use @code{-pix_fmts} to show all the supported
829pixel formats.
830If the selected pixel format can not be selected, ffmpeg will print a
831warning and select the best pixel format supported by the encoder.
832If @var{pix_fmt} is prefixed by a @code{+}, ffmpeg will exit with an error
833if the requested pixel format can not be selected, and automatic conversions
834inside filtergraphs are disabled.
835If @var{pix_fmt} is a single @code{+}, ffmpeg selects the same pixel format
836as the input (or graph output) and automatic conversions are disabled.
837
838@item -sws_flags @var{flags} (@emph{input/output})
839Set SwScaler flags.
840
841@item -rc_override[:@var{stream_specifier}] @var{override} (@emph{output,per-stream})
842Rate control override for specific intervals, formatted as "int,int,int"
843list separated with slashes. Two first values are the beginning and
844end frame numbers, last one is quantizer to use if positive, or quality
845factor if negative.
846
847@item -ilme
848Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
849Use this option if your input file is interlaced and you want
850to keep the interlaced format for minimum losses.
851The alternative is to deinterlace the input stream with
852@option{-deinterlace}, but deinterlacing introduces losses.
853@item -psnr
854Calculate PSNR of compressed frames.
855@item -vstats
856Dump video coding statistics to @file{vstats_HHMMSS.log}.
857@item -vstats_file @var{file}
858Dump video coding statistics to @var{file}.
859@item -vstats_version @var{file}
860Specifies which version of the vstats format to use. Default is 2.
861
862version = 1 :
863
864@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}
865
866version > 1:
867
868@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}
869@item -top[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
870top=1/bottom=0/auto=-1 field first
871@item -dc @var{precision}
872Intra_dc_precision.
873@item -vtag @var{fourcc/tag} (@emph{output})
874Force video tag/fourcc. This is an alias for @code{-tag:v}.
875@item -qphist (@emph{global})
876Show QP histogram
877@item -vbsf @var{bitstream_filter}
878Deprecated see -bsf
879
880@item -force_key_frames[:@var{stream_specifier}] @var{time}[,@var{time}...] (@emph{output,per-stream})
881@item -force_key_frames[:@var{stream_specifier}] expr:@var{expr} (@emph{output,per-stream})
882@item -force_key_frames[:@var{stream_specifier}] source (@emph{output,per-stream})
883
884@var{force_key_frames} can take arguments of the following form:
885
886@table @option
887
888@item @var{time}[,@var{time}...]
889If the argument consists of timestamps, ffmpeg will round the specified times to the nearest
890output timestamp as per the encoder time base and force a keyframe at the first frame having
891timestamp equal or greater than the computed timestamp. Note that if the encoder time base is too
892coarse, then the keyframes may be forced on frames with timestamps lower than the specified time.
893The default encoder time base is the inverse of the output framerate but may be set otherwise
894via @code{-enc_time_base}.
895
896If one of the times is "@code{chapters}[@var{delta}]", it is expanded into
897the time of the beginning of all chapters in the file, shifted by
898@var{delta}, expressed as a time in seconds.
899This option can be useful to ensure that a seek point is present at a
900chapter mark or any other designated place in the output file.
901
902For example, to insert a key frame at 5 minutes, plus key frames 0.1 second
903before the beginning of every chapter:
904@example
905-force_key_frames 0:05:00,chapters-0.1
906@end example
907
908@item expr:@var{expr}
909If the argument is prefixed with @code{expr:}, the string @var{expr}
910is interpreted like an expression and is evaluated for each frame. A
911key frame is forced in case the evaluation is non-zero.
912
913The expression in @var{expr} can contain the following constants:
914@table @option
915@item n
916the number of current processed frame, starting from 0
917@item n_forced
918the number of forced frames
919@item prev_forced_n
920the number of the previous forced frame, it is @code{NAN} when no
921keyframe was forced yet
922@item prev_forced_t
923the time of the previous forced frame, it is @code{NAN} when no
924keyframe was forced yet
925@item t
926the time of the current processed frame
927@end table
928
929For example to force a key frame every 5 seconds, you can specify:
930@example
931-force_key_frames expr:gte(t,n_forced*5)
932@end example
933
934To force a key frame 5 seconds after the time of the last forced one,
935starting from second 13:
936@example
937-force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5))
938@end example
939
940@item source
941If the argument is @code{source}, ffmpeg will force a key frame if
942the current frame being encoded is marked as a key frame in its source.
943
944@end table
945
946Note that forcing too many keyframes is very harmful for the lookahead
947algorithms of certain encoders: using fixed-GOP options or similar
948would be more efficient.
949
950@item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream})
951When doing stream copy, copy also non-key frames found at the
952beginning.
953
954@item -init_hw_device @var{type}[=@var{name}][:@var{device}[,@var{key=value}...]]
955Initialise a new hardware device of type @var{type} called @var{name}, using the
956given device parameters.
957If no name is specified it will receive a default name of the form "@var{type}%d".
958
959The meaning of @var{device} and the following arguments depends on the
960device type:
961@table @option
962
963@item cuda
964@var{device} is the number of the CUDA device.
965
966@item dxva2
967@var{device} is the number of the Direct3D 9 display adapter.
968
969@item vaapi
970@var{device} is either an X11 display name or a DRM render node.
971If not specified, it will attempt to open the default X11 display (@emph{$DISPLAY})
972and then the first DRM render node (@emph{/dev/dri/renderD128}).
973
974@item vdpau
975@var{device} is an X11 display name.
976If not specified, it will attempt to open the default X11 display (@emph{$DISPLAY}).
977
978@item qsv
979@var{device} selects a value in @samp{MFX_IMPL_*}. Allowed values are:
980@table @option
981@item auto
982@item sw
983@item hw
984@item auto_any
985@item hw_any
986@item hw2
987@item hw3
988@item hw4
989@end table
990If not specified, @samp{auto_any} is used.
991(Note that it may be easier to achieve the desired result for QSV by creating the
992platform-appropriate subdevice (@samp{dxva2} or @samp{vaapi}) and then deriving a
993QSV device from that.)
994
995@item opencl
996@var{device} selects the platform and device as @emph{platform_index.device_index}.
997
998The set of devices can also be filtered using the key-value pairs to find only
999devices matching particular platform or device strings.
1000
1001The strings usable as filters are:
1002@table @option
1003@item platform_profile
1004@item platform_version
1005@item platform_name
1006@item platform_vendor
1007@item platform_extensions
1008@item device_name
1009@item device_vendor
1010@item driver_version
1011@item device_version
1012@item device_profile
1013@item device_extensions
1014@item device_type
1015@end table
1016
1017The indices and filters must together uniquely select a device.
1018
1019Examples:
1020@table @emph
1021@item -init_hw_device opencl:0.1
1022Choose the second device on the first platform.
1023
1024@item -init_hw_device opencl:,device_name=Foo9000
1025Choose the device with a name containing the string @emph{Foo9000}.
1026
1027@item -init_hw_device opencl:1,device_type=gpu,device_extensions=cl_khr_fp16
1028Choose the GPU device on the second platform supporting the @emph{cl_khr_fp16}
1029extension.
1030@end table
1031
1032@item vulkan
1033If @var{device} is an integer, it selects the device by its index in a
1034system-dependent list of devices.  If @var{device} is any other string, it
1035selects the first device with a name containing that string as a substring.
1036
1037The following options are recognized:
1038@table @option
1039@item debug
1040If set to 1, enables the validation layer, if installed.
1041@item linear_images
1042If set to 1, images allocated by the hwcontext will be linear and locally mappable.
1043@item instance_extensions
1044A plus separated list of additional instance extensions to enable.
1045@item device_extensions
1046A plus separated list of additional device extensions to enable.
1047@end table
1048
1049Examples:
1050@table @emph
1051@item -init_hw_device vulkan:1
1052Choose the second device on the system.
1053
1054@item -init_hw_device vulkan:RADV
1055Choose the first device with a name containing the string @emph{RADV}.
1056
1057@item -init_hw_device vulkan:0,instance_extensions=VK_KHR_wayland_surface+VK_KHR_xcb_surface
1058Choose the first device and enable the Wayland and XCB instance extensions.
1059@end table
1060
1061@end table
1062
1063@item -init_hw_device @var{type}[=@var{name}]@@@var{source}
1064Initialise a new hardware device of type @var{type} called @var{name},
1065deriving it from the existing device with the name @var{source}.
1066
1067@item -init_hw_device list
1068List all hardware device types supported in this build of ffmpeg.
1069
1070@item -filter_hw_device @var{name}
1071Pass the hardware device called @var{name} to all filters in any filter graph.
1072This can be used to set the device to upload to with the @code{hwupload} filter,
1073or the device to map to with the @code{hwmap} filter.  Other filters may also
1074make use of this parameter when they require a hardware device.  Note that this
1075is typically only required when the input is not already in hardware frames -
1076when it is, filters will derive the device they require from the context of the
1077frames they receive as input.
1078
1079This is a global setting, so all filters will receive the same device.
1080
1081@item -hwaccel[:@var{stream_specifier}] @var{hwaccel} (@emph{input,per-stream})
1082Use hardware acceleration to decode the matching stream(s). The allowed values
1083of @var{hwaccel} are:
1084@table @option
1085@item none
1086Do not use any hardware acceleration (the default).
1087
1088@item auto
1089Automatically select the hardware acceleration method.
1090
1091@item vdpau
1092Use VDPAU (Video Decode and Presentation API for Unix) hardware acceleration.
1093
1094@item dxva2
1095Use DXVA2 (DirectX Video Acceleration) hardware acceleration.
1096
1097@item vaapi
1098Use VAAPI (Video Acceleration API) hardware acceleration.
1099
1100@item qsv
1101Use the Intel QuickSync Video acceleration for video transcoding.
1102
1103Unlike most other values, this option does not enable accelerated decoding (that
1104is used automatically whenever a qsv decoder is selected), but accelerated
1105transcoding, without copying the frames into the system memory.
1106
1107For it to work, both the decoder and the encoder must support QSV acceleration
1108and no filters must be used.
1109@end table
1110
1111This option has no effect if the selected hwaccel is not available or not
1112supported by the chosen decoder.
1113
1114Note that most acceleration methods are intended for playback and will not be
1115faster than software decoding on modern CPUs. Additionally, @command{ffmpeg}
1116will usually need to copy the decoded frames from the GPU memory into the system
1117memory, resulting in further performance loss. This option is thus mainly
1118useful for testing.
1119
1120@item -hwaccel_device[:@var{stream_specifier}] @var{hwaccel_device} (@emph{input,per-stream})
1121Select a device to use for hardware acceleration.
1122
1123This option only makes sense when the @option{-hwaccel} option is also specified.
1124It can either refer to an existing device created with @option{-init_hw_device}
1125by name, or it can create a new device as if
1126@samp{-init_hw_device} @var{type}:@var{hwaccel_device}
1127were called immediately before.
1128
1129@item -hwaccels
1130List all hardware acceleration methods supported in this build of ffmpeg.
1131
1132@end table
1133
1134@section Audio Options
1135
1136@table @option
1137@item -aframes @var{number} (@emph{output})
1138Set the number of audio frames to output. This is an obsolete alias for
1139@code{-frames:a}, which you should use instead.
1140@item -ar[:@var{stream_specifier}] @var{freq} (@emph{input/output,per-stream})
1141Set the audio sampling frequency. For output streams it is set by
1142default to the frequency of the corresponding input stream. For input
1143streams this option only makes sense for audio grabbing devices and raw
1144demuxers and is mapped to the corresponding demuxer options.
1145@item -aq @var{q} (@emph{output})
1146Set the audio quality (codec-specific, VBR). This is an alias for -q:a.
1147@item -ac[:@var{stream_specifier}] @var{channels} (@emph{input/output,per-stream})
1148Set the number of audio channels. For output streams it is set by
1149default to the number of input audio channels. For input streams
1150this option only makes sense for audio grabbing devices and raw demuxers
1151and is mapped to the corresponding demuxer options.
1152@item -an (@emph{input/output})
1153As an input option, blocks all audio streams of a file from being filtered or
1154being automatically selected or mapped for any output. See @code{-discard}
1155option to disable streams individually.
1156
1157As an output option, disables audio recording i.e. automatic selection or
1158mapping of any audio stream. For full manual control see the @code{-map}
1159option.
1160@item -acodec @var{codec} (@emph{input/output})
1161Set the audio codec. This is an alias for @code{-codec:a}.
1162@item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream})
1163Set the audio sample format. Use @code{-sample_fmts} to get a list
1164of supported sample formats.
1165
1166@item -af @var{filtergraph} (@emph{output})
1167Create the filtergraph specified by @var{filtergraph} and use it to
1168filter the stream.
1169
1170This is an alias for @code{-filter:a}, see the @ref{filter_option,,-filter option}.
1171@end table
1172
1173@section Advanced Audio options
1174
1175@table @option
1176@item -atag @var{fourcc/tag} (@emph{output})
1177Force audio tag/fourcc. This is an alias for @code{-tag:a}.
1178@item -absf @var{bitstream_filter}
1179Deprecated, see -bsf
1180@item -guess_layout_max @var{channels} (@emph{input,per-stream})
1181If some input channel layout is not known, try to guess only if it
1182corresponds to at most the specified number of channels. For example, 2
1183tells to @command{ffmpeg} to recognize 1 channel as mono and 2 channels as
1184stereo but not 6 channels as 5.1. The default is to always try to guess. Use
11850 to disable all guessing.
1186@end table
1187
1188@section Subtitle options
1189
1190@table @option
1191@item -scodec @var{codec} (@emph{input/output})
1192Set the subtitle codec. This is an alias for @code{-codec:s}.
1193@item -sn (@emph{input/output})
1194As an input option, blocks all subtitle streams of a file from being filtered or
1195being automatically selected or mapped for any output. See @code{-discard}
1196option to disable streams individually.
1197
1198As an output option, disables subtitle recording i.e. automatic selection or
1199mapping of any subtitle stream. For full manual control see the @code{-map}
1200option.
1201@item -sbsf @var{bitstream_filter}
1202Deprecated, see -bsf
1203@end table
1204
1205@section Advanced Subtitle options
1206
1207@table @option
1208
1209@item -fix_sub_duration
1210Fix subtitles durations. For each subtitle, wait for the next packet in the
1211same stream and adjust the duration of the first to avoid overlap. This is
1212necessary with some subtitles codecs, especially DVB subtitles, because the
1213duration in the original packet is only a rough estimate and the end is
1214actually marked by an empty subtitle frame. Failing to use this option when
1215necessary can result in exaggerated durations or muxing failures due to
1216non-monotonic timestamps.
1217
1218Note that this option will delay the output of all data until the next
1219subtitle packet is decoded: it may increase memory consumption and latency a
1220lot.
1221
1222@item -canvas_size @var{size}
1223Set the size of the canvas used to render subtitles.
1224
1225@end table
1226
1227@section Advanced options
1228
1229@table @option
1230@item -map [-]@var{input_file_id}[:@var{stream_specifier}][?][,@var{sync_file_id}[:@var{stream_specifier}]] | @var{[linklabel]} (@emph{output})
1231
1232Designate one or more input streams as a source for the output file. Each input
1233stream is identified by the input file index @var{input_file_id} and
1234the input stream index @var{input_stream_id} within the input
1235file. Both indices start at 0. If specified,
1236@var{sync_file_id}:@var{stream_specifier} sets which input stream
1237is used as a presentation sync reference.
1238
1239The first @code{-map} option on the command line specifies the
1240source for output stream 0, the second @code{-map} option specifies
1241the source for output stream 1, etc.
1242
1243A @code{-} character before the stream identifier creates a "negative" mapping.
1244It disables matching streams from already created mappings.
1245
1246A trailing @code{?} after the stream index will allow the map to be
1247optional: if the map matches no streams the map will be ignored instead
1248of failing. Note the map will still fail if an invalid input file index
1249is used; such as if the map refers to a non-existent input.
1250
1251An alternative @var{[linklabel]} form will map outputs from complex filter
1252graphs (see the @option{-filter_complex} option) to the output file.
1253@var{linklabel} must correspond to a defined output link label in the graph.
1254
1255For example, to map ALL streams from the first input file to output
1256@example
1257ffmpeg -i INPUT -map 0 output
1258@end example
1259
1260For example, if you have two audio streams in the first input file,
1261these streams are identified by "0:0" and "0:1". You can use
1262@code{-map} to select which streams to place in an output file. For
1263example:
1264@example
1265ffmpeg -i INPUT -map 0:1 out.wav
1266@end example
1267will map the input stream in @file{INPUT} identified by "0:1" to
1268the (single) output stream in @file{out.wav}.
1269
1270For example, to select the stream with index 2 from input file
1271@file{a.mov} (specified by the identifier "0:2"), and stream with
1272index 6 from input @file{b.mov} (specified by the identifier "1:6"),
1273and copy them to the output file @file{out.mov}:
1274@example
1275ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
1276@end example
1277
1278To select all video and the third audio stream from an input file:
1279@example
1280ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT
1281@end example
1282
1283To map all the streams except the second audio, use negative mappings
1284@example
1285ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT
1286@end example
1287
1288To map the video and audio streams from the first input, and using the
1289trailing @code{?}, ignore the audio mapping if no audio streams exist in
1290the first input:
1291@example
1292ffmpeg -i INPUT -map 0:v -map 0:a? OUTPUT
1293@end example
1294
1295To pick the English audio stream:
1296@example
1297ffmpeg -i INPUT -map 0:m:language:eng OUTPUT
1298@end example
1299
1300Note that using this option disables the default mappings for this output file.
1301
1302@item -ignore_unknown
1303Ignore input streams with unknown type instead of failing if copying
1304such streams is attempted.
1305
1306@item -copy_unknown
1307Allow input streams with unknown type to be copied instead of failing if copying
1308such streams is attempted.
1309
1310@item -map_channel [@var{input_file_id}.@var{stream_specifier}.@var{channel_id}|-1][?][:@var{output_file_id}.@var{stream_specifier}]
1311Map an audio channel from a given input to an output. If
1312@var{output_file_id}.@var{stream_specifier} is not set, the audio channel will
1313be mapped on all the audio streams.
1314
1315Using "-1" instead of
1316@var{input_file_id}.@var{stream_specifier}.@var{channel_id} will map a muted
1317channel.
1318
1319A trailing @code{?} will allow the map_channel to be
1320optional: if the map_channel matches no channel the map_channel will be ignored instead
1321of failing.
1322
1323For example, assuming @var{INPUT} is a stereo audio file, you can switch the
1324two audio channels with the following command:
1325@example
1326ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT
1327@end example
1328
1329If you want to mute the first channel and keep the second:
1330@example
1331ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT
1332@end example
1333
1334The order of the "-map_channel" option specifies the order of the channels in
1335the output stream. The output channel layout is guessed from the number of
1336channels mapped (mono if one "-map_channel", stereo if two, etc.). Using "-ac"
1337in combination of "-map_channel" makes the channel gain levels to be updated if
1338input and output channel layouts don't match (for instance two "-map_channel"
1339options and "-ac 6").
1340
1341You can also extract each channel of an input to specific outputs; the following
1342command extracts two channels of the @var{INPUT} audio stream (file 0, stream 0)
1343to the respective @var{OUTPUT_CH0} and @var{OUTPUT_CH1} outputs:
1344@example
1345ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1
1346@end example
1347
1348The following example splits the channels of a stereo input into two separate
1349streams, which are put into the same output file:
1350@example
1351ffmpeg -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
1352@end example
1353
1354Note that currently each output stream can only contain channels from a single
1355input stream; you can't for example use "-map_channel" to pick multiple input
1356audio channels contained in different streams (from the same or different files)
1357and merge them into a single output stream. It is therefore not currently
1358possible, for example, to turn two separate mono streams into a single stereo
1359stream. However splitting a stereo stream into two single channel mono streams
1360is possible.
1361
1362If you need this feature, a possible workaround is to use the @emph{amerge}
1363filter. For example, if you need to merge a media (here @file{input.mkv}) with 2
1364mono audio streams into one single stereo channel audio stream (and keep the
1365video stream), you can use the following command:
1366@example
1367ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv
1368@end example
1369
1370To map the first two audio channels from the first input, and using the
1371trailing @code{?}, ignore the audio channel mapping if the first input is
1372mono instead of stereo:
1373@example
1374ffmpeg -i INPUT -map_channel 0.0.0 -map_channel 0.0.1? OUTPUT
1375@end example
1376
1377@item -map_metadata[:@var{metadata_spec_out}] @var{infile}[:@var{metadata_spec_in}] (@emph{output,per-metadata})
1378Set metadata information of the next output file from @var{infile}. Note that
1379those are file indices (zero-based), not filenames.
1380Optional @var{metadata_spec_in/out} parameters specify, which metadata to copy.
1381A metadata specifier can have the following forms:
1382@table @option
1383@item @var{g}
1384global metadata, i.e. metadata that applies to the whole file
1385
1386@item @var{s}[:@var{stream_spec}]
1387per-stream metadata. @var{stream_spec} is a stream specifier as described
1388in the @ref{Stream specifiers} chapter. In an input metadata specifier, the first
1389matching stream is copied from. In an output metadata specifier, all matching
1390streams are copied to.
1391
1392@item @var{c}:@var{chapter_index}
1393per-chapter metadata. @var{chapter_index} is the zero-based chapter index.
1394
1395@item @var{p}:@var{program_index}
1396per-program metadata. @var{program_index} is the zero-based program index.
1397@end table
1398If metadata specifier is omitted, it defaults to global.
1399
1400By default, global metadata is copied from the first input file,
1401per-stream and per-chapter metadata is copied along with streams/chapters. These
1402default mappings are disabled by creating any mapping of the relevant type. A negative
1403file index can be used to create a dummy mapping that just disables automatic copying.
1404
1405For example to copy metadata from the first stream of the input file to global metadata
1406of the output file:
1407@example
1408ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3
1409@end example
1410
1411To do the reverse, i.e. copy global metadata to all audio streams:
1412@example
1413ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv
1414@end example
1415Note that simple @code{0} would work as well in this example, since global
1416metadata is assumed by default.
1417
1418@item -map_chapters @var{input_file_index} (@emph{output})
1419Copy chapters from input file with index @var{input_file_index} to the next
1420output file. If no chapter mapping is specified, then chapters are copied from
1421the first input file with at least one chapter. Use a negative file index to
1422disable any chapter copying.
1423
1424@item -benchmark (@emph{global})
1425Show benchmarking information at the end of an encode.
1426Shows real, system and user time used and maximum memory consumption.
1427Maximum memory consumption is not supported on all systems,
1428it will usually display as 0 if not supported.
1429@item -benchmark_all (@emph{global})
1430Show benchmarking information during the encode.
1431Shows real, system and user time used in various steps (audio/video encode/decode).
1432@item -timelimit @var{duration} (@emph{global})
1433Exit after ffmpeg has been running for @var{duration} seconds in CPU user time.
1434@item -dump (@emph{global})
1435Dump each input packet to stderr.
1436@item -hex (@emph{global})
1437When dumping packets, also dump the payload.
1438@item -re (@emph{input})
1439Read input at native frame rate. Mainly used to simulate a grab device,
1440or live input stream (e.g. when reading from a file). Should not be used
1441with actual grab devices or live input streams (where it can cause packet
1442loss).
1443By default @command{ffmpeg} attempts to read the input(s) as fast as possible.
1444This option will slow down the reading of the input(s) to the native frame rate
1445of the input(s). It is useful for real-time output (e.g. live streaming).
1446@item -vsync @var{parameter}
1447Video sync method.
1448For compatibility reasons old values can be specified as numbers.
1449Newly added values will have to be specified as strings always.
1450
1451@table @option
1452@item 0, passthrough
1453Each frame is passed with its timestamp from the demuxer to the muxer.
1454@item 1, cfr
1455Frames will be duplicated and dropped to achieve exactly the requested
1456constant frame rate.
1457@item 2, vfr
1458Frames are passed through with their timestamp or dropped so as to
1459prevent 2 frames from having the same timestamp.
1460@item drop
1461As passthrough but destroys all timestamps, making the muxer generate
1462fresh timestamps based on frame-rate.
1463@item -1, auto
1464Chooses between 1 and 2 depending on muxer capabilities. This is the
1465default method.
1466@end table
1467
1468Note that the timestamps may be further modified by the muxer, after this.
1469For example, in the case that the format option @option{avoid_negative_ts}
1470is enabled.
1471
1472With -map you can select from which stream the timestamps should be
1473taken. You can leave either video or audio unchanged and sync the
1474remaining stream(s) to the unchanged one.
1475
1476@item -frame_drop_threshold @var{parameter}
1477Frame drop threshold, which specifies how much behind video frames can
1478be before they are dropped. In frame rate units, so 1.0 is one frame.
1479The default is -1.1. One possible usecase is to avoid framedrops in case
1480of noisy timestamps or to increase frame drop precision in case of exact
1481timestamps.
1482
1483@item -async @var{samples_per_second}
1484Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
1485the parameter is the maximum samples per second by which the audio is changed.
1486-async 1 is a special case where only the start of the audio stream is corrected
1487without any later correction.
1488
1489Note that the timestamps may be further modified by the muxer, after this.
1490For example, in the case that the format option @option{avoid_negative_ts}
1491is enabled.
1492
1493This option has been deprecated. Use the @code{aresample} audio filter instead.
1494
1495@item -copyts
1496Do not process input timestamps, but keep their values without trying
1497to sanitize them. In particular, do not remove the initial start time
1498offset value.
1499
1500Note that, depending on the @option{vsync} option or on specific muxer
1501processing (e.g. in case the format option @option{avoid_negative_ts}
1502is enabled) the output timestamps may mismatch with the input
1503timestamps even when this option is selected.
1504
1505@item -start_at_zero
1506When used with @option{copyts}, shift input timestamps so they start at zero.
1507
1508This means that using e.g. @code{-ss 50} will make output timestamps start at
150950 seconds, regardless of what timestamp the input file started at.
1510
1511@item -copytb @var{mode}
1512Specify how to set the encoder timebase when stream copying.  @var{mode} is an
1513integer numeric value, and can assume one of the following values:
1514
1515@table @option
1516@item 1
1517Use the demuxer timebase.
1518
1519The time base is copied to the output encoder from the corresponding input
1520demuxer. This is sometimes required to avoid non monotonically increasing
1521timestamps when copying video streams with variable frame rate.
1522
1523@item 0
1524Use the decoder timebase.
1525
1526The time base is copied to the output encoder from the corresponding input
1527decoder.
1528
1529@item -1
1530Try to make the choice automatically, in order to generate a sane output.
1531@end table
1532
1533Default value is -1.
1534
1535@item -enc_time_base[:@var{stream_specifier}] @var{timebase} (@emph{output,per-stream})
1536Set the encoder timebase. @var{timebase} is a floating point number,
1537and can assume one of the following values:
1538
1539@table @option
1540@item 0
1541Assign a default value according to the media type.
1542
1543For video - use 1/framerate, for audio - use 1/samplerate.
1544
1545@item -1
1546Use the input stream timebase when possible.
1547
1548If an input stream is not available, the default timebase will be used.
1549
1550@item >0
1551Use the provided number as the timebase.
1552
1553This field can be provided as a ratio of two integers (e.g. 1:24, 1:48000)
1554or as a floating point number (e.g. 0.04166, 2.0833e-5)
1555@end table
1556
1557Default value is 0.
1558
1559@item -bitexact (@emph{input/output})
1560Enable bitexact mode for (de)muxer and (de/en)coder
1561@item -shortest (@emph{output})
1562Finish encoding when the shortest input stream ends.
1563@item -dts_delta_threshold
1564Timestamp discontinuity delta threshold.
1565@item -dts_error_threshold @var{seconds}
1566Timestamp error delta threshold. This threshold use to discard crazy/damaged
1567timestamps and the default is 30 hours which is arbitrarily picked and quite
1568conservative.
1569@item -muxdelay @var{seconds} (@emph{output})
1570Set the maximum demux-decode delay.
1571@item -muxpreload @var{seconds} (@emph{output})
1572Set the initial demux-decode delay.
1573@item -streamid @var{output-stream-index}:@var{new-value} (@emph{output})
1574Assign a new stream-id value to an output stream. This option should be
1575specified prior to the output filename to which it applies.
1576For the situation where multiple output files exist, a streamid
1577may be reassigned to a different value.
1578
1579For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for
1580an output mpegts file:
1581@example
1582ffmpeg -i inurl -streamid 0:33 -streamid 1:36 out.ts
1583@end example
1584
1585@item -bsf[:@var{stream_specifier}] @var{bitstream_filters} (@emph{output,per-stream})
1586Set bitstream filters for matching streams. @var{bitstream_filters} is
1587a comma-separated list of bitstream filters. Use the @code{-bsfs} option
1588to get the list of bitstream filters.
1589@example
1590ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264
1591@end example
1592@example
1593ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt
1594@end example
1595
1596@item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{input/output,per-stream})
1597Force a tag/fourcc for matching streams.
1598
1599@item -timecode @var{hh}:@var{mm}:@var{ss}SEP@var{ff}
1600Specify Timecode for writing. @var{SEP} is ':' for non drop timecode and ';'
1601(or '.') for drop.
1602@example
1603ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg
1604@end example
1605
1606@anchor{filter_complex_option}
1607@item -filter_complex @var{filtergraph} (@emph{global})
1608Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
1609outputs. For simple graphs -- those with one input and one output of the same
1610type -- see the @option{-filter} options. @var{filtergraph} is a description of
1611the filtergraph, as described in the ``Filtergraph syntax'' section of the
1612ffmpeg-filters manual.
1613
1614Input link labels must refer to input streams using the
1615@code{[file_index:stream_specifier]} syntax (i.e. the same as @option{-map}
1616uses). If @var{stream_specifier} matches multiple streams, the first one will be
1617used. An unlabeled input will be connected to the first unused input stream of
1618the matching type.
1619
1620Output link labels are referred to with @option{-map}. Unlabeled outputs are
1621added to the first output file.
1622
1623Note that with this option it is possible to use only lavfi sources without
1624normal input files.
1625
1626For example, to overlay an image over video
1627@example
1628ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
1629'[out]' out.mkv
1630@end example
1631Here @code{[0:v]} refers to the first video stream in the first input file,
1632which is linked to the first (main) input of the overlay filter. Similarly the
1633first video stream in the second input is linked to the second (overlay) input
1634of overlay.
1635
1636Assuming there is only one video stream in each input file, we can omit input
1637labels, so the above is equivalent to
1638@example
1639ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map
1640'[out]' out.mkv
1641@end example
1642
1643Furthermore we can omit the output label and the single output from the filter
1644graph will be added to the output file automatically, so we can simply write
1645@example
1646ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv
1647@end example
1648
1649To generate 5 seconds of pure red video using lavfi @code{color} source:
1650@example
1651ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv
1652@end example
1653
1654@item -filter_complex_threads @var{nb_threads} (@emph{global})
1655Defines how many threads are used to process a filter_complex graph.
1656Similar to filter_threads but used for @code{-filter_complex} graphs only.
1657The default is the number of available CPUs.
1658
1659@item -lavfi @var{filtergraph} (@emph{global})
1660Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
1661outputs. Equivalent to @option{-filter_complex}.
1662
1663@item -filter_complex_script @var{filename} (@emph{global})
1664This option is similar to @option{-filter_complex}, the only difference is that
1665its argument is the name of the file from which a complex filtergraph
1666description is to be read.
1667
1668@item -accurate_seek (@emph{input})
1669This option enables or disables accurate seeking in input files with the
1670@option{-ss} option. It is enabled by default, so seeking is accurate when
1671transcoding. Use @option{-noaccurate_seek} to disable it, which may be useful
1672e.g. when copying some streams and transcoding the others.
1673
1674@item -seek_timestamp (@emph{input})
1675This option enables or disables seeking by timestamp in input files with the
1676@option{-ss} option. It is disabled by default. If enabled, the argument
1677to the @option{-ss} option is considered an actual timestamp, and is not
1678offset by the start time of the file. This matters only for files which do
1679not start from timestamp 0, such as transport streams.
1680
1681@item -thread_queue_size @var{size} (@emph{input})
1682This option sets the maximum number of queued packets when reading from the
1683file or device. With low latency / high rate live streams, packets may be
1684discarded if they are not read in a timely manner; raising this value can
1685avoid it.
1686
1687@item -sdp_file @var{file} (@emph{global})
1688Print sdp information for an output stream to @var{file}.
1689This allows dumping sdp information when at least one output isn't an
1690rtp stream. (Requires at least one of the output formats to be rtp).
1691
1692@item -discard (@emph{input})
1693Allows discarding specific streams or frames from streams.
1694Any input stream can be fully discarded, using value @code{all} whereas
1695selective discarding of frames from a stream occurs at the demuxer
1696and is not supported by all demuxers.
1697
1698@table @option
1699@item none
1700Discard no frame.
1701
1702@item default
1703Default, which discards no frames.
1704
1705@item noref
1706Discard all non-reference frames.
1707
1708@item bidir
1709Discard all bidirectional frames.
1710
1711@item nokey
1712Discard all frames excepts keyframes.
1713
1714@item all
1715Discard all frames.
1716@end table
1717
1718@item -abort_on @var{flags} (@emph{global})
1719Stop and abort on various conditions. The following flags are available:
1720
1721@table @option
1722@item empty_output
1723No packets were passed to the muxer, the output is empty.
1724@item empty_output_stream
1725No packets were passed to the muxer in some of the output streams.
1726@end table
1727
1728@item -xerror (@emph{global})
1729Stop and exit on error
1730
1731@item -max_muxing_queue_size @var{packets} (@emph{output,per-stream})
1732When transcoding audio and/or video streams, ffmpeg will not begin writing into
1733the output until it has one packet for each such stream. While waiting for that
1734to happen, packets for other streams are buffered. This option sets the size of
1735this buffer, in packets, for the matching output stream.
1736
1737The default value of this option should be high enough for most uses, so only
1738touch this option if you are sure that you need it.
1739
1740@end table
1741
1742As a special exception, you can use a bitmap subtitle stream as input: it
1743will be converted into a video with the same size as the largest video in
1744the file, or 720x576 if no video is present. Note that this is an
1745experimental and temporary solution. It will be removed once libavfilter has
1746proper support for subtitles.
1747
1748For example, to hardcode subtitles on top of a DVB-T recording stored in
1749MPEG-TS format, delaying the subtitles by 1 second:
1750@example
1751ffmpeg -i input.ts -filter_complex \
1752  '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
1753  -sn -map '#0x2dc' output.mkv
1754@end example
1755(0x2d0, 0x2dc and 0x2ef are the MPEG-TS PIDs of respectively the video,
1756audio and subtitles streams; 0:0, 0:3 and 0:7 would have worked too)
1757
1758@section Preset files
1759A preset file contains a sequence of @var{option}=@var{value} pairs,
1760one for each line, specifying a sequence of options which would be
1761awkward to specify on the command line. Lines starting with the hash
1762('#') character are ignored and are used to provide comments. Check
1763the @file{presets} directory in the FFmpeg source tree for examples.
1764
1765There are two types of preset files: ffpreset and avpreset files.
1766
1767@subsection ffpreset files
1768ffpreset files are specified with the @code{vpre}, @code{apre},
1769@code{spre}, and @code{fpre} options. The @code{fpre} option takes the
1770filename of the preset instead of a preset name as input and can be
1771used for any kind of codec. For the @code{vpre}, @code{apre}, and
1772@code{spre} options, the options specified in a preset file are
1773applied to the currently selected codec of the same type as the preset
1774option.
1775
1776The argument passed to the @code{vpre}, @code{apre}, and @code{spre}
1777preset options identifies the preset file to use according to the
1778following rules:
1779
1780First ffmpeg searches for a file named @var{arg}.ffpreset in the
1781directories @file{$FFMPEG_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
1782the datadir defined at configuration time (usually @file{PREFIX/share/ffmpeg})
1783or in a @file{ffpresets} folder along the executable on win32,
1784in that order. For example, if the argument is @code{libvpx-1080p}, it will
1785search for the file @file{libvpx-1080p.ffpreset}.
1786
1787If no such file is found, then ffmpeg will search for a file named
1788@var{codec_name}-@var{arg}.ffpreset in the above-mentioned
1789directories, where @var{codec_name} is the name of the codec to which
1790the preset file options will be applied. For example, if you select
1791the video codec with @code{-vcodec libvpx} and use @code{-vpre 1080p},
1792then it will search for the file @file{libvpx-1080p.ffpreset}.
1793
1794@subsection avpreset files
1795avpreset files are specified with the @code{pre} option. They work similar to
1796ffpreset files, but they only allow encoder- specific options. Therefore, an
1797@var{option}=@var{value} pair specifying an encoder cannot be used.
1798
1799When the @code{pre} option is specified, ffmpeg will look for files with the
1800suffix .avpreset in the directories @file{$AVCONV_DATADIR} (if set), and
1801@file{$HOME/.avconv}, and in the datadir defined at configuration time (usually
1802@file{PREFIX/share/ffmpeg}), in that order.
1803
1804First ffmpeg searches for a file named @var{codec_name}-@var{arg}.avpreset in
1805the above-mentioned directories, where @var{codec_name} is the name of the codec
1806to which the preset file options will be applied. For example, if you select the
1807video codec with @code{-vcodec libvpx} and use @code{-pre 1080p}, then it will
1808search for the file @file{libvpx-1080p.avpreset}.
1809
1810If no such file is found, then ffmpeg will search for a file named
1811@var{arg}.avpreset in the same directories.
1812
1813@c man end OPTIONS
1814
1815@chapter Examples
1816@c man begin EXAMPLES
1817
1818@section Video and Audio grabbing
1819
1820If you specify the input format and device then ffmpeg can grab video
1821and audio directly.
1822
1823@example
1824ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
1825@end example
1826
1827Or with an ALSA audio source (mono input, card id 1) instead of OSS:
1828@example
1829ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg
1830@end example
1831
1832Note that you must activate the right video source and channel before
1833launching ffmpeg with any TV viewer such as
1834@uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also
1835have to set the audio recording levels correctly with a
1836standard mixer.
1837
1838@section X11 grabbing
1839
1840Grab the X11 display with ffmpeg via
1841
1842@example
1843ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0 /tmp/out.mpg
1844@end example
1845
18460.0 is display.screen number of your X11 server, same as
1847the DISPLAY environment variable.
1848
1849@example
1850ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0+10,20 /tmp/out.mpg
1851@end example
1852
18530.0 is display.screen number of your X11 server, same as the DISPLAY environment
1854variable. 10 is the x-offset and 20 the y-offset for the grabbing.
1855
1856@section Video and Audio file format conversion
1857
1858Any supported file format and protocol can serve as input to ffmpeg:
1859
1860Examples:
1861@itemize
1862@item
1863You can use YUV files as input:
1864
1865@example
1866ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
1867@end example
1868
1869It will use the files:
1870@example
1871/tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
1872/tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
1873@end example
1874
1875The Y files use twice the resolution of the U and V files. They are
1876raw files, without header. They can be generated by all decent video
1877decoders. You must specify the size of the image with the @option{-s} option
1878if ffmpeg cannot guess it.
1879
1880@item
1881You can input from a raw YUV420P file:
1882
1883@example
1884ffmpeg -i /tmp/test.yuv /tmp/out.avi
1885@end example
1886
1887test.yuv is a file containing raw YUV planar data. Each frame is composed
1888of the Y plane followed by the U and V planes at half vertical and
1889horizontal resolution.
1890
1891@item
1892You can output to a raw YUV420P file:
1893
1894@example
1895ffmpeg -i mydivx.avi hugefile.yuv
1896@end example
1897
1898@item
1899You can set several input files and output files:
1900
1901@example
1902ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
1903@end example
1904
1905Converts the audio file a.wav and the raw YUV video file a.yuv
1906to MPEG file a.mpg.
1907
1908@item
1909You can also do audio and video conversions at the same time:
1910
1911@example
1912ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
1913@end example
1914
1915Converts a.wav to MPEG audio at 22050 Hz sample rate.
1916
1917@item
1918You can encode to several formats at the same time and define a
1919mapping from input stream to output streams:
1920
1921@example
1922ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2
1923@end example
1924
1925Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
1926file:index' specifies which input stream is used for each output
1927stream, in the order of the definition of output streams.
1928
1929@item
1930You can transcode decrypted VOBs:
1931
1932@example
1933ffmpeg -i snatch_1.vob -f avi -c:v mpeg4 -b:v 800k -g 300 -bf 2 -c:a libmp3lame -b:a 128k snatch.avi
1934@end example
1935
1936This is a typical DVD ripping example; the input is a VOB file, the
1937output an AVI file with MPEG-4 video and MP3 audio. Note that in this
1938command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
1939GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
1940input video. Furthermore, the audio stream is MP3-encoded so you need
1941to enable LAME support by passing @code{--enable-libmp3lame} to configure.
1942The mapping is particularly useful for DVD transcoding
1943to get the desired audio language.
1944
1945NOTE: To see the supported input formats, use @code{ffmpeg -demuxers}.
1946
1947@item
1948You can extract images from a video, or create a video from many images:
1949
1950For extracting images from a video:
1951@example
1952ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
1953@end example
1954
1955This will extract one video frame per second from the video and will
1956output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg},
1957etc. Images will be rescaled to fit the new WxH values.
1958
1959If you want to extract just a limited number of frames, you can use the
1960above command in combination with the @code{-frames:v} or @code{-t} option,
1961or in combination with -ss to start extracting from a certain point in time.
1962
1963For creating a video from many images:
1964@example
1965ffmpeg -f image2 -framerate 12 -i foo-%03d.jpeg -s WxH foo.avi
1966@end example
1967
1968The syntax @code{foo-%03d.jpeg} specifies to use a decimal number
1969composed of three digits padded with zeroes to express the sequence
1970number. It is the same syntax supported by the C printf function, but
1971only formats accepting a normal integer are suitable.
1972
1973When importing an image sequence, -i also supports expanding
1974shell-like wildcard patterns (globbing) internally, by selecting the
1975image2-specific @code{-pattern_type glob} option.
1976
1977For example, for creating a video from filenames matching the glob pattern
1978@code{foo-*.jpeg}:
1979@example
1980ffmpeg -f image2 -pattern_type glob -framerate 12 -i 'foo-*.jpeg' -s WxH foo.avi
1981@end example
1982
1983@item
1984You can put many streams of the same type in the output:
1985
1986@example
1987ffmpeg -i test1.avi -i test2.avi -map 1:1 -map 1:0 -map 0:1 -map 0:0 -c copy -y test12.nut
1988@end example
1989
1990The resulting output file @file{test12.nut} will contain the first four streams
1991from the input files in reverse order.
1992
1993@item
1994To force CBR video output:
1995@example
1996ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
1997@end example
1998
1999@item
2000The four options lmin, lmax, mblmin and mblmax use 'lambda' units,
2001but you may use the QP2LAMBDA constant to easily convert from 'q' units:
2002@example
2003ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
2004@end example
2005
2006@end itemize
2007@c man end EXAMPLES
2008
2009@include config.texi
2010@ifset config-all
2011@ifset config-avutil
2012@include utils.texi
2013@end ifset
2014@ifset config-avcodec
2015@include codecs.texi
2016@include bitstream_filters.texi
2017@end ifset
2018@ifset config-avformat
2019@include formats.texi
2020@include protocols.texi
2021@end ifset
2022@ifset config-avdevice
2023@include devices.texi
2024@end ifset
2025@ifset config-swresample
2026@include resampler.texi
2027@end ifset
2028@ifset config-swscale
2029@include scaler.texi
2030@end ifset
2031@ifset config-avfilter
2032@include filters.texi
2033@end ifset
2034@end ifset
2035
2036@chapter See Also
2037
2038@ifhtml
2039@ifset config-all
2040@url{ffmpeg.html,ffmpeg}
2041@end ifset
2042@ifset config-not-all
2043@url{ffmpeg-all.html,ffmpeg-all},
2044@end ifset
2045@url{ffplay.html,ffplay}, @url{ffprobe.html,ffprobe},
2046@url{ffmpeg-utils.html,ffmpeg-utils},
2047@url{ffmpeg-scaler.html,ffmpeg-scaler},
2048@url{ffmpeg-resampler.html,ffmpeg-resampler},
2049@url{ffmpeg-codecs.html,ffmpeg-codecs},
2050@url{ffmpeg-bitstream-filters.html,ffmpeg-bitstream-filters},
2051@url{ffmpeg-formats.html,ffmpeg-formats},
2052@url{ffmpeg-devices.html,ffmpeg-devices},
2053@url{ffmpeg-protocols.html,ffmpeg-protocols},
2054@url{ffmpeg-filters.html,ffmpeg-filters}
2055@end ifhtml
2056
2057@ifnothtml
2058@ifset config-all
2059ffmpeg(1),
2060@end ifset
2061@ifset config-not-all
2062ffmpeg-all(1),
2063@end ifset
2064ffplay(1), ffprobe(1),
2065ffmpeg-utils(1), ffmpeg-scaler(1), ffmpeg-resampler(1),
2066ffmpeg-codecs(1), ffmpeg-bitstream-filters(1), ffmpeg-formats(1),
2067ffmpeg-devices(1), ffmpeg-protocols(1), ffmpeg-filters(1)
2068@end ifnothtml
2069
2070@include authors.texi
2071
2072@ignore
2073
2074@setfilename ffmpeg
2075@settitle ffmpeg video converter
2076
2077@end ignore
2078
2079@bye
2080