1 \input texinfo @c -*- texinfo -*-
2 @documentencoding UTF-8
4 @settitle ffmpeg Documentation
6 @center @titlefont{ffmpeg Documentation}
15 ffmpeg [@var{global_options}] @{[@var{input_file_options}] -i @file{input_url}@} ... @{[@var{output_file_options}] @file{output_url}@} ...
18 @c man begin DESCRIPTION
20 @command{ffmpeg} is a very fast video and audio converter that can also grab from
21 a live audio/video source. It can also convert between arbitrary sample
22 rates and resize video on the fly with a high quality polyphase filter.
24 @command{ffmpeg} reads from an arbitrary number of input "files" (which can be regular
25 files, pipes, network streams, grabbing devices, etc.), specified by the
26 @code{-i} option, and writes to an arbitrary number of output "files", which are
27 specified by a plain output url. Anything found on the command line which
28 cannot be interpreted as an option is considered to be an output url.
30 Each input or output url can, in principle, contain any number of streams of
31 different types (video/audio/subtitle/attachment/data). The allowed number and/or
32 types of streams may be limited by the container format. Selecting which
33 streams from which inputs will go into which output is either done automatically
34 or with the @code{-map} option (see the Stream selection chapter).
36 To refer to input files in options, you must use their indices (0-based). E.g.
37 the first input file is @code{0}, the second is @code{1}, etc. Similarly, streams
38 within a file are referred to by their indices. E.g. @code{2:3} refers to the
39 fourth stream in the third input file. Also see the Stream specifiers chapter.
41 As a general rule, options are applied to the next specified
42 file. Therefore, order is important, and you can have the same
43 option on the command line multiple times. Each occurrence is
44 then applied to the next input or output file.
45 Exceptions from this rule are the global options (e.g. verbosity level),
46 which should be specified first.
48 Do not mix input and output files -- first specify all input files, then all
49 output files. Also do not mix options which belong to different files. All
50 options apply ONLY to the next input or output file and are reset between files.
54 To set the video bitrate of the output file to 64 kbit/s:
56 ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi
60 To force the frame rate of the output file to 24 fps:
62 ffmpeg -i input.avi -r 24 output.avi
66 To force the frame rate of the input file (valid for raw formats only)
67 to 1 fps and the frame rate of the output file to 24 fps:
69 ffmpeg -r 1 -i input.m2v -r 24 output.avi
73 The format option may be needed for raw input files.
75 @c man end DESCRIPTION
77 @chapter Detailed description
78 @c man begin DETAILED DESCRIPTION
80 The transcoding process in @command{ffmpeg} for each output can be described by
81 the following diagram:
84 _______ ______________
86 | input | demuxer | encoded data | decoder
87 | file | ---------> | packets | -----+
88 |_______| |______________| |
95 ________ ______________ |
97 | output | <-------- | encoded data | <----+
98 | file | muxer | packets | encoder
99 |________| |______________|
104 @command{ffmpeg} calls the libavformat library (containing demuxers) to read
105 input files and get packets containing encoded data from them. When there are
106 multiple input files, @command{ffmpeg} tries to keep them synchronized by
107 tracking lowest timestamp on any active input stream.
109 Encoded packets are then passed to the decoder (unless streamcopy is selected
110 for the stream, see further for a description). The decoder produces
111 uncompressed frames (raw video/PCM audio/...) which can be processed further by
112 filtering (see next section). After filtering, the frames are passed to the
113 encoder, which encodes them and outputs encoded packets. Finally those are
114 passed to the muxer, which writes the encoded packets to the output file.
117 Before encoding, @command{ffmpeg} can process raw audio and video frames using
118 filters from the libavfilter library. Several chained filters form a filter
119 graph. @command{ffmpeg} distinguishes between two types of filtergraphs:
122 @subsection Simple filtergraphs
123 Simple filtergraphs are those that have exactly one input and output, both of
124 the same type. In the above diagram they can be represented by simply inserting
125 an additional step between decoding and encoding:
128 _________ ______________
130 | decoded | | encoded data |
131 | frames |\ _ | packets |
132 |_________| \ /||______________|
134 simple _\|| | / encoder
135 filtergraph | filtered |/
141 Simple filtergraphs are configured with the per-stream @option{-filter} option
142 (with @option{-vf} and @option{-af} aliases for video and audio respectively).
143 A simple filtergraph for video can look for example like this:
146 _______ _____________ _______ ________
148 | input | ---> | deinterlace | ---> | scale | ---> | output |
149 |_______| |_____________| |_______| |________|
153 Note 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
155 touch the frame contents. Another example is the @code{setpts} filter, which
156 only sets timestamps and otherwise passes the frames unchanged.
158 @subsection Complex filtergraphs
159 Complex filtergraphs are those which cannot be described as simply a linear
160 processing chain applied to one stream. This is the case, for example, when the graph has
161 more than one input and/or output, or when output stream type is different from
162 input. They can be represented with the following diagram:
167 | input 0 |\ __________
169 \ _________ /| output 0 |
171 _________ \| complex | /
173 | input 1 |---->| filter |\
174 |_________| | | \ __________
177 _________ / |_________| |__________|
184 Complex filtergraphs are configured with the @option{-filter_complex} option.
185 Note that this option is global, since a complex filtergraph, by its nature,
186 cannot be unambiguously associated with a single stream or file.
188 The @option{-lavfi} option is equivalent to @option{-filter_complex}.
190 A trivial example of a complex filtergraph is the @code{overlay} filter, which
191 has two video inputs and one video output, containing one video overlaid on top
192 of the other. Its audio counterpart is the @code{amix} filter.
195 Stream 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
197 step for the specified stream, so it does only demuxing and muxing. It is useful
198 for changing the container format or modifying container-level metadata. The
199 diagram above will, in this case, simplify to this:
202 _______ ______________ ________
204 | input | demuxer | encoded data | muxer | output |
205 | file | ---------> | packets | -------> | file |
206 |_______| |______________| |________|
210 Since there is no decoding or encoding, it is very fast and there is no quality
211 loss. However, it might not work in some cases because of many factors. Applying
212 filters is obviously also impossible, since filters work on uncompressed data.
214 @c man end DETAILED DESCRIPTION
216 @chapter Stream selection
217 @c man begin STREAM SELECTION
219 @command{ffmpeg} provides the @code{-map} option for manual control of stream selection in each
220 output file. Users can skip @code{-map} and let ffmpeg perform automatic stream selection as
221 described below. The @code{-vn / -an / -sn / -dn} options can be used to skip inclusion of
222 video, audio, subtitle and data streams respectively, whether manually mapped or automatically
223 selected, except for those streams which are outputs of complex filtergraphs.
226 The sub-sections that follow describe the various rules that are involved in stream selection.
227 The examples that follow next show how these rules are applied in practice.
229 While every effort is made to accurately reflect the behavior of the program, FFmpeg is under
230 continuous development and the code may have changed since the time of this writing.
232 @subsection Automatic stream selection
234 In the absence of any map options for a particular output file, ffmpeg inspects the output
235 format to check which type of streams can be included in it, viz. video, audio and/or
236 subtitles. For each acceptable stream type, ffmpeg will pick one stream, when available,
237 from among all the inputs.
239 It will select that stream based upon the following criteria:
242 for video, it is the stream with the highest resolution,
244 for audio, it is the stream with the most channels,
246 for subtitles, it is the first subtitle stream found but there's a caveat.
247 The output format's default subtitle encoder can be either text-based or image-based,
248 and only a subtitle stream of the same type will be chosen.
251 In the case where several streams of the same type rate equally, the stream with the lowest
254 Data or attachment streams are not automatically selected and can only be included
256 @subsection Manual stream selection
258 When @code{-map} is used, only user-mapped streams are included in that output file,
259 with one possible exception for filtergraph outputs described below.
261 @subsection Complex filtergraphs
263 If there are any complex filtergraph output streams with unlabeled pads, they will be added
264 to the first output file. This will lead to a fatal error if the stream type is not supported
265 by the output format. In the absence of the map option, the inclusion of these streams leads
266 to the automatic stream selection of their types being skipped. If map options are present,
267 these filtergraph streams are included in addition to the mapped streams.
269 Complex filtergraph output streams with labeled pads must be mapped once and exactly once.
271 @subsection Stream handling
273 Stream handling is independent of stream selection, with an exception for subtitles described
274 below. Stream handling is set via the @code{-codec} option addressed to streams within a
275 specific @emph{output} file. In particular, codec options are applied by ffmpeg after the
276 stream selection process and thus do not influence the latter. If no @code{-codec} option is
277 specified for a stream type, ffmpeg will select the default encoder registered by the output
280 An exception exists for subtitles. If a subtitle encoder is specified for an output file, the
281 first subtitle stream found of any type, text or image, will be included. ffmpeg does not validate
282 if the specified encoder can convert the selected stream or if the converted stream is acceptable
283 within the output format. This applies generally as well: when the user sets an encoder manually,
284 the stream selection process cannot check if the encoded stream can be muxed into the output file.
285 If it cannot, ffmpeg will abort and @emph{all} output files will fail to be processed.
289 The following examples illustrate the behavior, quirks and limitations of ffmpeg's stream
292 They assume the following three input files.
297 stream 0: video 640x360
298 stream 1: audio 2 channels
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)
308 stream 0: video 1280x720
309 stream 1: audio 2 channels
310 stream 2: subtitles (image)
313 @subsubheading Example: automatic stream selection
315 ffmpeg -i A.avi -i B.mp4 out1.mkv out2.wav -map 1:a -c:a copy out3.mov
317 There are three output files specified, and for the first two, no @code{-map} options
318 are set, so ffmpeg will select streams for these two files automatically.
320 @file{out1.mkv} is a Matroska container file and accepts video, audio and subtitle streams,
321 so ffmpeg will try to select one of each type.@*
322 For video, it will select @code{stream 0} from @file{B.mp4}, which has the highest
323 resolution among all the input video streams.@*
324 For audio, it will select @code{stream 3} from @file{B.mp4}, since it has the greatest
325 number of channels.@*
326 For subtitles, it will select @code{stream 2} from @file{B.mp4}, which is the first subtitle
327 stream from among @file{A.avi} and @file{B.mp4}.
329 @file{out2.wav} accepts only audio streams, so only @code{stream 3} from @file{B.mp4} is
332 For @file{out3.mov}, since a @code{-map} option is set, no automatic stream selection will
333 occur. 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.
336 For the first two outputs, all included streams will be transcoded. The encoders chosen will
337 be the default ones registered by each output format, which may not match the codec of the
338 selected input streams.
340 For the third output, codec option for audio streams has been set
341 to @code{copy}, so no decoding-filtering-encoding operations will occur, or @emph{can} occur.
342 Packets of selected streams shall be conveyed from the input file and muxed within the output
345 @subsubheading Example: automatic subtitles selection
347 ffmpeg -i C.mkv out1.mkv -c:s dvdsub -an out2.mkv
349 Although @file{out1.mkv} is a Matroska container file which accepts subtitle streams, only a
350 video and audio stream shall be selected. The subtitle stream of @file{C.mkv} is image-based
351 and the default subtitle encoder of the Matroska muxer is text-based, so a transcode operation
352 for 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
354 selected, in addition to the video stream. The presence of @code{-an} disables audio stream
355 selection for @file{out2.mkv}.
357 @subsubheading Example: unlabeled filtergraph outputs
359 ffmpeg -i A.avi -i C.mkv -i B.mp4 -filter_complex "overlay" out1.mp4 out2.srt
361 A filtergraph is setup here using the @code{-filter_complex} option and consists of a single
362 video filter. The @code{overlay} filter requires exactly two video inputs, but none are
363 specified, 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
366 have selected the stream in @file{B.mp4}. The audio stream with most channels viz. @code{stream 3}
367 in @file{B.mp4}, is chosen automatically. No subtitle stream is chosen however, since the MP4
368 format has no default subtitle encoder registered, and the user hasn't specified a subtitle encoder.
370 The 2nd output file, @file{out2.srt}, only accepts text-based subtitle streams. So, even though
371 the first subtitle stream available belongs to @file{C.mkv}, it is image-based and hence skipped.
372 The selected stream, @code{stream 2} in @file{B.mp4}, is the first text-based subtitle stream.
374 @subsubheading Example: labeled filtergraph outputs
376 ffmpeg -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 \
379 -map '[outv]' -map 1:a:0 out3.mkv
382 The above command will fail, as the output pad labelled @code{[outv]} has been mapped twice.
383 None of the output files shall be processed.
386 ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0[outv];overlay;aresample" \
392 This command above will also fail as the hue filter output has a label, @code{[outv]},
393 and hasn't been mapped anywhere.
395 The command should be modified as follows,
397 ffmpeg -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 \
400 -map '[outv2]' -map 1:a:0 out3.mkv
402 The video stream from @file{B.mp4} is sent to the hue filter, whose output is cloned once using
403 the split filter, and both outputs labelled. Then a copy each is mapped to the first and third
406 The overlay filter, requiring two video inputs, uses the first two unused video streams. Those
407 are the streams from @file{A.avi} and @file{C.mkv}. The overlay output isn't labelled, so it is
408 sent to the first output file @file{out1.mp4}, regardless of the presence of the @code{-map} option.
410 The aresample filter is sent the first unused audio stream, that of @file{A.avi}. Since this filter
411 output is also unlabelled, it too is mapped to the first output file. The presence of @code{-an}
412 only suppresses automatic or manual stream selection of audio streams, not outputs sent from
413 filtergraphs. Both these mapped streams shall be ordered before the mapped stream in @file{out1.mp4}.
415 The video, audio and subtitle streams mapped to @code{out2.mkv} are entirely determined by
416 automatic stream selection.
418 @file{out3.mkv} consists of the cloned video output from the hue filter and the first audio
419 stream from @file{B.mp4}.
422 @c man end STREAM SELECTION
427 @include fftools-common-opts.texi
429 @section Main options
433 @item -f @var{fmt} (@emph{input/output})
434 Force input or output file format. The format is normally auto detected for input
435 files and guessed from the file extension for output files, so this option is not
436 needed in most cases.
438 @item -i @var{url} (@emph{input})
441 @item -y (@emph{global})
442 Overwrite output files without asking.
444 @item -n (@emph{global})
445 Do not overwrite output files, and exit immediately if a specified
446 output file already exists.
448 @item -stream_loop @var{number} (@emph{input})
449 Set number of times input stream shall be looped. Loop 0 means no loop,
450 loop -1 means infinite loop.
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})
454 Select an encoder (when used before an output file) or a decoder (when used
455 before an input file) for one or more streams. @var{codec} is the name of a
456 decoder/encoder or a special value @code{copy} (output only) to indicate that
457 the stream is not to be re-encoded.
461 ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT
463 encodes all video streams with libx264 and copies all audio streams.
465 For each stream, the last matching @code{c} option is applied, so
467 ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT
469 will copy all the streams except the second video, which will be encoded with
470 libx264, and the 138th audio, which will be encoded with libvorbis.
472 @item -t @var{duration} (@emph{input/output})
473 When used as an input option (before @code{-i}), limit the @var{duration} of
474 data read from the input file.
476 When used as an output option (before an output url), stop writing the
477 output after its duration reaches @var{duration}.
479 @var{duration} must be a time duration specification,
480 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
482 -to and -t are mutually exclusive and -t has priority.
484 @item -to @var{position} (@emph{input/output})
485 Stop writing the output or reading the input at @var{position}.
486 @var{position} must be a time duration specification,
487 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
489 -to and -t are mutually exclusive and -t has priority.
491 @item -fs @var{limit_size} (@emph{output})
492 Set the file size limit, expressed in bytes. No further chunk of bytes is written
493 after the limit is exceeded. The size of the output file is slightly more than the
496 @item -ss @var{position} (@emph{input/output})
497 When 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,
499 so @command{ffmpeg} will seek to the closest seek point before @var{position}.
500 When transcoding and @option{-accurate_seek} is enabled (the default), this
501 extra segment between the seek point and @var{position} will be decoded and
502 discarded. When doing stream copy or when @option{-noaccurate_seek} is used, it
505 When used as an output option (before an output url), decodes but discards
506 input until the timestamps reach @var{position}.
508 @var{position} must be a time duration specification,
509 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
511 @item -sseof @var{position} (@emph{input})
513 Like the @code{-ss} option but relative to the "end of file". That is negative
514 values are earlier in the file, 0 is at EOF.
516 @item -itsoffset @var{offset} (@emph{input})
517 Set the input time offset.
519 @var{offset} must be a time duration specification,
520 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
522 The offset is added to the timestamps of the input files. Specifying
523 a positive offset means that the corresponding streams are delayed by
524 the time duration specified in @var{offset}.
526 @item -itsscale @var{scale} (@emph{input,per-stream})
527 Rescale input timestamps. @var{scale} should be a floating point number.
529 @item -timestamp @var{date} (@emph{output})
530 Set the recording timestamp in the container.
532 @var{date} must be a date specification,
533 see @ref{date syntax,,the Date section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
535 @item -metadata[:metadata_specifier] @var{key}=@var{value} (@emph{output,per-metadata})
536 Set a metadata key/value pair.
538 An optional @var{metadata_specifier} may be given to set metadata
539 on streams, chapters or programs. See @code{-map_metadata}
540 documentation for details.
542 This option overrides metadata set with @code{-map_metadata}. It is
543 also possible to delete metadata by using an empty value.
545 For example, for setting the title in the output file:
547 ffmpeg -i in.avi -metadata title="my title" out.flv
550 To set the language of the first audio stream:
552 ffmpeg -i INPUT -metadata:s:a:0 language=eng OUTPUT
555 @item -disposition[:stream_specifier] @var{value} (@emph{output,per-stream})
556 Sets the disposition for a stream.
558 This option overrides the disposition copied from the input stream. It is also
559 possible to delete the disposition by setting it to 0.
561 The following dispositions are recognized:
570 @item hearing_impaired
571 @item visual_impaired
580 For example, to make the second audio stream the default stream:
582 ffmpeg -i in.mkv -c copy -disposition:a:1 default out.mkv
585 To make the second subtitle stream the default stream and remove the default
586 disposition from the first subtitle stream:
588 ffmpeg -i in.mkv -c copy -disposition:s:0 0 -disposition:s:1 default out.mkv
591 To add an embedded cover/thumbnail:
593 ffmpeg -i in.mp4 -i IMAGE -map 0 -map 1 -c copy -c:v:1 png -disposition:v:1 attached_pic out.mp4
596 Not all muxers support embedded thumbnails, and those who do, only support a few formats, like JPEG or PNG.
598 @item -program [title=@var{title}:][program_num=@var{program_num}:]st=@var{stream}[:st=@var{stream}...] (@emph{output})
600 Creates a program with the specified @var{title}, @var{program_num} and adds the specified
601 @var{stream}(s) to it.
603 @item -target @var{type} (@emph{output})
604 Specify 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:
610 ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
613 Nevertheless you can specify additional options as long as you know
614 they do not conflict with the standard, as in:
617 ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
620 @item -dn (@emph{input/output})
621 As an input option, blocks all data streams of a file from being filtered or
622 being automatically selected or mapped for any output. See @code{-discard}
623 option to disable streams individually.
625 As an output option, disables data recording i.e. automatic selection or
626 mapping of any data stream. For full manual control see the @code{-map}
629 @item -dframes @var{number} (@emph{output})
630 Set the number of data frames to output. This is an obsolete alias for
631 @code{-frames:d}, which you should use instead.
633 @item -frames[:@var{stream_specifier}] @var{framecount} (@emph{output,per-stream})
634 Stop writing to the stream after @var{framecount} frames.
636 @item -q[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
637 @itemx -qscale[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
638 Use fixed quality scale (VBR). The meaning of @var{q}/@var{qscale} is
640 If @var{qscale} is used without a @var{stream_specifier} then it applies only
641 to the video stream, this is to maintain compatibility with previous behavior
642 and as specifying the same codec specific value to 2 different codecs that is
643 audio and video generally is not what is intended when no stream_specifier is
646 @anchor{filter_option}
647 @item -filter[:@var{stream_specifier}] @var{filtergraph} (@emph{output,per-stream})
648 Create the filtergraph specified by @var{filtergraph} and use it to
651 @var{filtergraph} is a description of the filtergraph to apply to
652 the stream, and must have a single input and a single output of the
653 same type of the stream. In the filtergraph, the input is associated
654 to the label @code{in}, and the output to the label @code{out}. See
655 the ffmpeg-filters manual for more information about the filtergraph
658 See the @ref{filter_complex_option,,-filter_complex option} if you
659 want to create filtergraphs with multiple inputs and/or outputs.
661 @item -filter_script[:@var{stream_specifier}] @var{filename} (@emph{output,per-stream})
662 This option is similar to @option{-filter}, the only difference is that its
663 argument is the name of the file from which a filtergraph description is to be
666 @item -filter_threads @var{nb_threads} (@emph{global})
667 Defines how many threads are used to process a filter pipeline. Each pipeline
668 will produce a thread pool with this many threads available for parallel processing.
669 The default is the number of available CPUs.
671 @item -pre[:@var{stream_specifier}] @var{preset_name} (@emph{output,per-stream})
672 Specify the preset for matching stream(s).
674 @item -stats (@emph{global})
675 Print encoding progress/statistics. It is on by default, to explicitly
676 disable it you need to specify @code{-nostats}.
678 @item -progress @var{url} (@emph{global})
679 Send program-friendly progress information to @var{url}.
681 Progress information is written approximately every second and at the end of
682 the encoding process. It is made of "@var{key}=@var{value}" lines. @var{key}
683 consists of only alphanumeric characters. The last key of a sequence of
684 progress information is always "progress".
686 @anchor{stdin option}
688 Enable interaction on standard input. On by default unless standard input is
689 used as an input. To explicitly disable interaction you need to specify
692 Disabling interaction on standard input is useful, for example, if
693 ffmpeg is in the background process group. Roughly the same result can
694 be achieved with @code{ffmpeg ... < /dev/null} but it requires a
697 @item -debug_ts (@emph{global})
698 Print timestamp information. It is off by default. This option is
699 mostly useful for testing and debugging purposes, and the output
700 format may change from one version to another, so it should not be
701 employed by portable scripts.
703 See also the option @code{-fdebug ts}.
705 @item -attach @var{filename} (@emph{output})
706 Add an attachment to the output file. This is supported by a few formats
707 like Matroska for e.g. fonts used in rendering subtitles. Attachments
708 are implemented as a specific type of stream, so this option will add
709 a new stream to the file. It is then possible to use per-stream options
710 on this stream in the usual way. Attachment streams created with this
711 option will be created after all the other streams (i.e. those created
712 with @code{-map} or automatic mappings).
714 Note that for Matroska you also have to set the mimetype metadata tag:
716 ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv
718 (assuming that the attachment stream will be third in the output file).
720 @item -dump_attachment[:@var{stream_specifier}] @var{filename} (@emph{input,per-stream})
721 Extract 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
725 E.g. to extract the first attachment to a file named 'out.ttf':
727 ffmpeg -dump_attachment:t:0 out.ttf -i INPUT
729 To extract all attachments to files determined by the @code{filename} tag:
731 ffmpeg -dump_attachment:t "" -i INPUT
734 Technical note -- attachments are implemented as codec extradata, so this
735 option can actually be used to extract extradata from any stream, not just
739 Disable automatically rotating video based on file metadata.
743 @section Video Options
746 @item -vframes @var{number} (@emph{output})
747 Set 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})
750 Set frame rate (Hz value, fraction or abbreviation).
752 As an input option, ignore any timestamps stored in the file and instead
753 generate timestamps assuming constant frame rate @var{fps}.
754 This is not the same as the @option{-framerate} option used for some input formats
755 like image2 or v4l2 (it used to be the same in older versions of FFmpeg).
756 If in doubt use @option{-framerate} instead of the input option @option{-r}.
758 As an output option, duplicate or drop input frames to achieve constant output
759 frame rate @var{fps}.
761 @item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream})
764 As an input option, this is a shortcut for the @option{video_size} private
765 option, recognized by some demuxers for which the frame size is either not
766 stored in the file or is configurable -- e.g. raw video or video grabbers.
768 As 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
770 directly to insert it at the beginning or some other place.
772 The format is @samp{wxh} (default - same as source).
774 @item -aspect[:@var{stream_specifier}] @var{aspect} (@emph{output,per-stream})
775 Set the video display aspect ratio specified by @var{aspect}.
777 @var{aspect} can be a floating point number string, or a string of the
778 form @var{num}:@var{den}, where @var{num} and @var{den} are the
779 numerator and denominator of the aspect ratio. For example "4:3",
780 "16:9", "1.3333", and "1.7777" are valid argument values.
782 If used together with @option{-vcodec copy}, it will affect the aspect ratio
783 stored at container level, but not the aspect ratio stored in encoded
784 frames, if it exists.
786 @item -vn (@emph{input/output})
787 As an input option, blocks all video streams of a file from being filtered or
788 being automatically selected or mapped for any output. See @code{-discard}
789 option to disable streams individually.
791 As an output option, disables video recording i.e. automatic selection or
792 mapping of any video stream. For full manual control see the @code{-map}
795 @item -vcodec @var{codec} (@emph{output})
796 Set the video codec. This is an alias for @code{-codec:v}.
798 @item -pass[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
799 Select the pass number (1 or 2). It is used to do two-pass
800 video encoding. The statistics of the video are recorded in the first
801 pass into a log file (see also the option -passlogfile),
802 and in the second pass that log file is used to generate the video
803 at the exact requested bitrate.
804 On pass 1, you may just deactivate audio and set output to null,
805 examples for Windows and Unix:
807 ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
808 ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null
811 @item -passlogfile[:@var{stream_specifier}] @var{prefix} (@emph{output,per-stream})
812 Set two-pass log file name prefix to @var{prefix}, the default file name
813 prefix is ``ffmpeg2pass''. The complete file name will be
814 @file{PREFIX-N.log}, where N is a number specific to the output
817 @item -vf @var{filtergraph} (@emph{output})
818 Create the filtergraph specified by @var{filtergraph} and use it to
821 This is an alias for @code{-filter:v}, see the @ref{filter_option,,-filter option}.
824 @section Advanced Video options
827 @item -pix_fmt[:@var{stream_specifier}] @var{format} (@emph{input/output,per-stream})
828 Set pixel format. Use @code{-pix_fmts} to show all the supported
830 If the selected pixel format can not be selected, ffmpeg will print a
831 warning and select the best pixel format supported by the encoder.
832 If @var{pix_fmt} is prefixed by a @code{+}, ffmpeg will exit with an error
833 if the requested pixel format can not be selected, and automatic conversions
834 inside filtergraphs are disabled.
835 If @var{pix_fmt} is a single @code{+}, ffmpeg selects the same pixel format
836 as the input (or graph output) and automatic conversions are disabled.
838 @item -sws_flags @var{flags} (@emph{input/output})
841 @item -rc_override[:@var{stream_specifier}] @var{override} (@emph{output,per-stream})
842 Rate control override for specific intervals, formatted as "int,int,int"
843 list separated with slashes. Two first values are the beginning and
844 end frame numbers, last one is quantizer to use if positive, or quality
848 Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
849 Use this option if your input file is interlaced and you want
850 to keep the interlaced format for minimum losses.
851 The alternative is to deinterlace the input stream with
852 @option{-deinterlace}, but deinterlacing introduces losses.
854 Calculate PSNR of compressed frames.
856 Dump video coding statistics to @file{vstats_HHMMSS.log}.
857 @item -vstats_file @var{file}
858 Dump video coding statistics to @var{file}.
859 @item -vstats_version @var{file}
860 Specifies which version of the vstats format to use. Default is 2.
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}
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})
870 top=1/bottom=0/auto=-1 field first
871 @item -dc @var{precision}
873 @item -vtag @var{fourcc/tag} (@emph{output})
874 Force video tag/fourcc. This is an alias for @code{-tag:v}.
875 @item -qphist (@emph{global})
877 @item -vbsf @var{bitstream_filter}
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 Force key frames at the specified timestamps, more precisely at the first
883 frames after each specified time.
885 If the argument is prefixed with @code{expr:}, the string @var{expr}
886 is interpreted like an expression and is evaluated for each frame. A
887 key frame is forced in case the evaluation is non-zero.
889 If one of the times is "@code{chapters}[@var{delta}]", it is expanded into
890 the time of the beginning of all chapters in the file, shifted by
891 @var{delta}, expressed as a time in seconds.
892 This option can be useful to ensure that a seek point is present at a
893 chapter mark or any other designated place in the output file.
895 For example, to insert a key frame at 5 minutes, plus key frames 0.1 second
896 before the beginning of every chapter:
898 -force_key_frames 0:05:00,chapters-0.1
901 The expression in @var{expr} can contain the following constants:
904 the number of current processed frame, starting from 0
906 the number of forced frames
908 the number of the previous forced frame, it is @code{NAN} when no
909 keyframe was forced yet
911 the time of the previous forced frame, it is @code{NAN} when no
912 keyframe was forced yet
914 the time of the current processed frame
917 For example to force a key frame every 5 seconds, you can specify:
919 -force_key_frames expr:gte(t,n_forced*5)
922 To force a key frame 5 seconds after the time of the last forced one,
923 starting from second 13:
925 -force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5))
928 Note that forcing too many keyframes is very harmful for the lookahead
929 algorithms of certain encoders: using fixed-GOP options or similar
930 would be more efficient.
932 @item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream})
933 When doing stream copy, copy also non-key frames found at the
936 @item -init_hw_device @var{type}[=@var{name}][:@var{device}[,@var{key=value}...]]
937 Initialise a new hardware device of type @var{type} called @var{name}, using the
938 given device parameters.
939 If no name is specified it will receive a default name of the form "@var{type}%d".
941 The meaning of @var{device} and the following arguments depends on the
946 @var{device} is the number of the CUDA device.
949 @var{device} is the number of the Direct3D 9 display adapter.
952 @var{device} is either an X11 display name or a DRM render node.
953 If not specified, it will attempt to open the default X11 display (@emph{$DISPLAY})
954 and then the first DRM render node (@emph{/dev/dri/renderD128}).
957 @var{device} is an X11 display name.
958 If not specified, it will attempt to open the default X11 display (@emph{$DISPLAY}).
961 @var{device} selects a value in @samp{MFX_IMPL_*}. Allowed values are:
972 If not specified, @samp{auto_any} is used.
973 (Note that it may be easier to achieve the desired result for QSV by creating the
974 platform-appropriate subdevice (@samp{dxva2} or @samp{vaapi}) and then deriving a
975 QSV device from that.)
978 @var{device} selects the platform and device as @emph{platform_index.device_index}.
980 The set of devices can also be filtered using the key-value pairs to find only
981 devices matching particular platform or device strings.
983 The strings usable as filters are:
985 @item platform_profile
986 @item platform_version
988 @item platform_vendor
989 @item platform_extensions
995 @item device_extensions
999 The indices and filters must together uniquely select a device.
1003 @item -init_hw_device opencl:0.1
1004 Choose the second device on the first platform.
1006 @item -init_hw_device opencl:,device_name=Foo9000
1007 Choose the device with a name containing the string @emph{Foo9000}.
1009 @item -init_hw_device opencl:1,device_type=gpu,device_extensions=cl_khr_fp16
1010 Choose the GPU device on the second platform supporting the @emph{cl_khr_fp16}
1016 @item -init_hw_device @var{type}[=@var{name}]@@@var{source}
1017 Initialise a new hardware device of type @var{type} called @var{name},
1018 deriving it from the existing device with the name @var{source}.
1020 @item -init_hw_device list
1021 List all hardware device types supported in this build of ffmpeg.
1023 @item -filter_hw_device @var{name}
1024 Pass the hardware device called @var{name} to all filters in any filter graph.
1025 This can be used to set the device to upload to with the @code{hwupload} filter,
1026 or the device to map to with the @code{hwmap} filter. Other filters may also
1027 make use of this parameter when they require a hardware device. Note that this
1028 is typically only required when the input is not already in hardware frames -
1029 when it is, filters will derive the device they require from the context of the
1030 frames they receive as input.
1032 This is a global setting, so all filters will receive the same device.
1034 @item -hwaccel[:@var{stream_specifier}] @var{hwaccel} (@emph{input,per-stream})
1035 Use hardware acceleration to decode the matching stream(s). The allowed values
1036 of @var{hwaccel} are:
1039 Do not use any hardware acceleration (the default).
1042 Automatically select the hardware acceleration method.
1045 Use VDPAU (Video Decode and Presentation API for Unix) hardware acceleration.
1048 Use DXVA2 (DirectX Video Acceleration) hardware acceleration.
1051 Use VAAPI (Video Acceleration API) hardware acceleration.
1054 Use the Intel QuickSync Video acceleration for video transcoding.
1056 Unlike most other values, this option does not enable accelerated decoding (that
1057 is used automatically whenever a qsv decoder is selected), but accelerated
1058 transcoding, without copying the frames into the system memory.
1060 For it to work, both the decoder and the encoder must support QSV acceleration
1061 and no filters must be used.
1064 This option has no effect if the selected hwaccel is not available or not
1065 supported by the chosen decoder.
1067 Note that most acceleration methods are intended for playback and will not be
1068 faster than software decoding on modern CPUs. Additionally, @command{ffmpeg}
1069 will usually need to copy the decoded frames from the GPU memory into the system
1070 memory, resulting in further performance loss. This option is thus mainly
1073 @item -hwaccel_device[:@var{stream_specifier}] @var{hwaccel_device} (@emph{input,per-stream})
1074 Select a device to use for hardware acceleration.
1076 This option only makes sense when the @option{-hwaccel} option is also specified.
1077 It can either refer to an existing device created with @option{-init_hw_device}
1078 by name, or it can create a new device as if
1079 @samp{-init_hw_device} @var{type}:@var{hwaccel_device}
1080 were called immediately before.
1083 List all hardware acceleration methods supported in this build of ffmpeg.
1087 @section Audio Options
1090 @item -aframes @var{number} (@emph{output})
1091 Set the number of audio frames to output. This is an obsolete alias for
1092 @code{-frames:a}, which you should use instead.
1093 @item -ar[:@var{stream_specifier}] @var{freq} (@emph{input/output,per-stream})
1094 Set the audio sampling frequency. For output streams it is set by
1095 default to the frequency of the corresponding input stream. For input
1096 streams this option only makes sense for audio grabbing devices and raw
1097 demuxers and is mapped to the corresponding demuxer options.
1098 @item -aq @var{q} (@emph{output})
1099 Set the audio quality (codec-specific, VBR). This is an alias for -q:a.
1100 @item -ac[:@var{stream_specifier}] @var{channels} (@emph{input/output,per-stream})
1101 Set the number of audio channels. For output streams it is set by
1102 default to the number of input audio channels. For input streams
1103 this option only makes sense for audio grabbing devices and raw demuxers
1104 and is mapped to the corresponding demuxer options.
1105 @item -an (@emph{input/output})
1106 As an input option, blocks all audio streams of a file from being filtered or
1107 being automatically selected or mapped for any output. See @code{-discard}
1108 option to disable streams individually.
1110 As an output option, disables audio recording i.e. automatic selection or
1111 mapping of any audio stream. For full manual control see the @code{-map}
1113 @item -acodec @var{codec} (@emph{input/output})
1114 Set the audio codec. This is an alias for @code{-codec:a}.
1115 @item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream})
1116 Set the audio sample format. Use @code{-sample_fmts} to get a list
1117 of supported sample formats.
1119 @item -af @var{filtergraph} (@emph{output})
1120 Create the filtergraph specified by @var{filtergraph} and use it to
1123 This is an alias for @code{-filter:a}, see the @ref{filter_option,,-filter option}.
1126 @section Advanced Audio options
1129 @item -atag @var{fourcc/tag} (@emph{output})
1130 Force audio tag/fourcc. This is an alias for @code{-tag:a}.
1131 @item -absf @var{bitstream_filter}
1132 Deprecated, see -bsf
1133 @item -guess_layout_max @var{channels} (@emph{input,per-stream})
1134 If some input channel layout is not known, try to guess only if it
1135 corresponds to at most the specified number of channels. For example, 2
1136 tells to @command{ffmpeg} to recognize 1 channel as mono and 2 channels as
1137 stereo but not 6 channels as 5.1. The default is to always try to guess. Use
1138 0 to disable all guessing.
1141 @section Subtitle options
1144 @item -scodec @var{codec} (@emph{input/output})
1145 Set the subtitle codec. This is an alias for @code{-codec:s}.
1146 @item -sn (@emph{input/output})
1147 As an input option, blocks all subtitle streams of a file from being filtered or
1148 being automatically selected or mapped for any output. See @code{-discard}
1149 option to disable streams individually.
1151 As an output option, disables subtitle recording i.e. automatic selection or
1152 mapping of any subtitle stream. For full manual control see the @code{-map}
1154 @item -sbsf @var{bitstream_filter}
1155 Deprecated, see -bsf
1158 @section Advanced Subtitle options
1162 @item -fix_sub_duration
1163 Fix subtitles durations. For each subtitle, wait for the next packet in the
1164 same stream and adjust the duration of the first to avoid overlap. This is
1165 necessary with some subtitles codecs, especially DVB subtitles, because the
1166 duration in the original packet is only a rough estimate and the end is
1167 actually marked by an empty subtitle frame. Failing to use this option when
1168 necessary can result in exaggerated durations or muxing failures due to
1169 non-monotonic timestamps.
1171 Note that this option will delay the output of all data until the next
1172 subtitle packet is decoded: it may increase memory consumption and latency a
1175 @item -canvas_size @var{size}
1176 Set the size of the canvas used to render subtitles.
1180 @section Advanced options
1183 @item -map [-]@var{input_file_id}[:@var{stream_specifier}][?][,@var{sync_file_id}[:@var{stream_specifier}]] | @var{[linklabel]} (@emph{output})
1185 Designate one or more input streams as a source for the output file. Each input
1186 stream is identified by the input file index @var{input_file_id} and
1187 the input stream index @var{input_stream_id} within the input
1188 file. Both indices start at 0. If specified,
1189 @var{sync_file_id}:@var{stream_specifier} sets which input stream
1190 is used as a presentation sync reference.
1192 The first @code{-map} option on the command line specifies the
1193 source for output stream 0, the second @code{-map} option specifies
1194 the source for output stream 1, etc.
1196 A @code{-} character before the stream identifier creates a "negative" mapping.
1197 It disables matching streams from already created mappings.
1199 A trailing @code{?} after the stream index will allow the map to be
1200 optional: if the map matches no streams the map will be ignored instead
1201 of failing. Note the map will still fail if an invalid input file index
1202 is used; such as if the map refers to a non-existent input.
1204 An alternative @var{[linklabel]} form will map outputs from complex filter
1205 graphs (see the @option{-filter_complex} option) to the output file.
1206 @var{linklabel} must correspond to a defined output link label in the graph.
1208 For example, to map ALL streams from the first input file to output
1210 ffmpeg -i INPUT -map 0 output
1213 For example, if you have two audio streams in the first input file,
1214 these streams are identified by "0:0" and "0:1". You can use
1215 @code{-map} to select which streams to place in an output file. For
1218 ffmpeg -i INPUT -map 0:1 out.wav
1220 will map the input stream in @file{INPUT} identified by "0:1" to
1221 the (single) output stream in @file{out.wav}.
1223 For example, to select the stream with index 2 from input file
1224 @file{a.mov} (specified by the identifier "0:2"), and stream with
1225 index 6 from input @file{b.mov} (specified by the identifier "1:6"),
1226 and copy them to the output file @file{out.mov}:
1228 ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
1231 To select all video and the third audio stream from an input file:
1233 ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT
1236 To map all the streams except the second audio, use negative mappings
1238 ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT
1241 To map the video and audio streams from the first input, and using the
1242 trailing @code{?}, ignore the audio mapping if no audio streams exist in
1245 ffmpeg -i INPUT -map 0:v -map 0:a? OUTPUT
1248 To pick the English audio stream:
1250 ffmpeg -i INPUT -map 0:m:language:eng OUTPUT
1253 Note that using this option disables the default mappings for this output file.
1255 @item -ignore_unknown
1256 Ignore input streams with unknown type instead of failing if copying
1257 such streams is attempted.
1260 Allow input streams with unknown type to be copied instead of failing if copying
1261 such streams is attempted.
1263 @item -map_channel [@var{input_file_id}.@var{stream_specifier}.@var{channel_id}|-1][?][:@var{output_file_id}.@var{stream_specifier}]
1264 Map an audio channel from a given input to an output. If
1265 @var{output_file_id}.@var{stream_specifier} is not set, the audio channel will
1266 be mapped on all the audio streams.
1268 Using "-1" instead of
1269 @var{input_file_id}.@var{stream_specifier}.@var{channel_id} will map a muted
1272 A trailing @code{?} will allow the map_channel to be
1273 optional: if the map_channel matches no channel the map_channel will be ignored instead
1276 For example, assuming @var{INPUT} is a stereo audio file, you can switch the
1277 two audio channels with the following command:
1279 ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT
1282 If you want to mute the first channel and keep the second:
1284 ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT
1287 The order of the "-map_channel" option specifies the order of the channels in
1288 the output stream. The output channel layout is guessed from the number of
1289 channels mapped (mono if one "-map_channel", stereo if two, etc.). Using "-ac"
1290 in combination of "-map_channel" makes the channel gain levels to be updated if
1291 input and output channel layouts don't match (for instance two "-map_channel"
1292 options and "-ac 6").
1294 You can also extract each channel of an input to specific outputs; the following
1295 command extracts two channels of the @var{INPUT} audio stream (file 0, stream 0)
1296 to the respective @var{OUTPUT_CH0} and @var{OUTPUT_CH1} outputs:
1298 ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1
1301 The following example splits the channels of a stereo input into two separate
1302 streams, which are put into the same output file:
1304 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
1307 Note that currently each output stream can only contain channels from a single
1308 input stream; you can't for example use "-map_channel" to pick multiple input
1309 audio channels contained in different streams (from the same or different files)
1310 and merge them into a single output stream. It is therefore not currently
1311 possible, for example, to turn two separate mono streams into a single stereo
1312 stream. However splitting a stereo stream into two single channel mono streams
1315 If you need this feature, a possible workaround is to use the @emph{amerge}
1316 filter. For example, if you need to merge a media (here @file{input.mkv}) with 2
1317 mono audio streams into one single stereo channel audio stream (and keep the
1318 video stream), you can use the following command:
1320 ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv
1323 To map the first two audio channels from the first input, and using the
1324 trailing @code{?}, ignore the audio channel mapping if the first input is
1325 mono instead of stereo:
1327 ffmpeg -i INPUT -map_channel 0.0.0 -map_channel 0.0.1? OUTPUT
1330 @item -map_metadata[:@var{metadata_spec_out}] @var{infile}[:@var{metadata_spec_in}] (@emph{output,per-metadata})
1331 Set metadata information of the next output file from @var{infile}. Note that
1332 those are file indices (zero-based), not filenames.
1333 Optional @var{metadata_spec_in/out} parameters specify, which metadata to copy.
1334 A metadata specifier can have the following forms:
1337 global metadata, i.e. metadata that applies to the whole file
1339 @item @var{s}[:@var{stream_spec}]
1340 per-stream metadata. @var{stream_spec} is a stream specifier as described
1341 in the @ref{Stream specifiers} chapter. In an input metadata specifier, the first
1342 matching stream is copied from. In an output metadata specifier, all matching
1343 streams are copied to.
1345 @item @var{c}:@var{chapter_index}
1346 per-chapter metadata. @var{chapter_index} is the zero-based chapter index.
1348 @item @var{p}:@var{program_index}
1349 per-program metadata. @var{program_index} is the zero-based program index.
1351 If metadata specifier is omitted, it defaults to global.
1353 By default, global metadata is copied from the first input file,
1354 per-stream and per-chapter metadata is copied along with streams/chapters. These
1355 default mappings are disabled by creating any mapping of the relevant type. A negative
1356 file index can be used to create a dummy mapping that just disables automatic copying.
1358 For example to copy metadata from the first stream of the input file to global metadata
1361 ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3
1364 To do the reverse, i.e. copy global metadata to all audio streams:
1366 ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv
1368 Note that simple @code{0} would work as well in this example, since global
1369 metadata is assumed by default.
1371 @item -map_chapters @var{input_file_index} (@emph{output})
1372 Copy chapters from input file with index @var{input_file_index} to the next
1373 output file. If no chapter mapping is specified, then chapters are copied from
1374 the first input file with at least one chapter. Use a negative file index to
1375 disable any chapter copying.
1377 @item -benchmark (@emph{global})
1378 Show benchmarking information at the end of an encode.
1379 Shows real, system and user time used and maximum memory consumption.
1380 Maximum memory consumption is not supported on all systems,
1381 it will usually display as 0 if not supported.
1382 @item -benchmark_all (@emph{global})
1383 Show benchmarking information during the encode.
1384 Shows real, system and user time used in various steps (audio/video encode/decode).
1385 @item -timelimit @var{duration} (@emph{global})
1386 Exit after ffmpeg has been running for @var{duration} seconds in CPU user time.
1387 @item -dump (@emph{global})
1388 Dump each input packet to stderr.
1389 @item -hex (@emph{global})
1390 When dumping packets, also dump the payload.
1391 @item -re (@emph{input})
1392 Read input at native frame rate. Mainly used to simulate a grab device,
1393 or live input stream (e.g. when reading from a file). Should not be used
1394 with actual grab devices or live input streams (where it can cause packet
1396 By default @command{ffmpeg} attempts to read the input(s) as fast as possible.
1397 This option will slow down the reading of the input(s) to the native frame rate
1398 of the input(s). It is useful for real-time output (e.g. live streaming).
1399 @item -vsync @var{parameter}
1401 For compatibility reasons old values can be specified as numbers.
1402 Newly added values will have to be specified as strings always.
1405 @item 0, passthrough
1406 Each frame is passed with its timestamp from the demuxer to the muxer.
1408 Frames will be duplicated and dropped to achieve exactly the requested
1409 constant frame rate.
1411 Frames are passed through with their timestamp or dropped so as to
1412 prevent 2 frames from having the same timestamp.
1414 As passthrough but destroys all timestamps, making the muxer generate
1415 fresh timestamps based on frame-rate.
1417 Chooses between 1 and 2 depending on muxer capabilities. This is the
1421 Note that the timestamps may be further modified by the muxer, after this.
1422 For example, in the case that the format option @option{avoid_negative_ts}
1425 With -map you can select from which stream the timestamps should be
1426 taken. You can leave either video or audio unchanged and sync the
1427 remaining stream(s) to the unchanged one.
1429 @item -frame_drop_threshold @var{parameter}
1430 Frame drop threshold, which specifies how much behind video frames can
1431 be before they are dropped. In frame rate units, so 1.0 is one frame.
1432 The default is -1.1. One possible usecase is to avoid framedrops in case
1433 of noisy timestamps or to increase frame drop precision in case of exact
1436 @item -async @var{samples_per_second}
1437 Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
1438 the parameter is the maximum samples per second by which the audio is changed.
1439 -async 1 is a special case where only the start of the audio stream is corrected
1440 without any later correction.
1442 Note that the timestamps may be further modified by the muxer, after this.
1443 For example, in the case that the format option @option{avoid_negative_ts}
1446 This option has been deprecated. Use the @code{aresample} audio filter instead.
1449 Do not process input timestamps, but keep their values without trying
1450 to sanitize them. In particular, do not remove the initial start time
1453 Note that, depending on the @option{vsync} option or on specific muxer
1454 processing (e.g. in case the format option @option{avoid_negative_ts}
1455 is enabled) the output timestamps may mismatch with the input
1456 timestamps even when this option is selected.
1458 @item -start_at_zero
1459 When used with @option{copyts}, shift input timestamps so they start at zero.
1461 This means that using e.g. @code{-ss 50} will make output timestamps start at
1462 50 seconds, regardless of what timestamp the input file started at.
1464 @item -copytb @var{mode}
1465 Specify how to set the encoder timebase when stream copying. @var{mode} is an
1466 integer numeric value, and can assume one of the following values:
1470 Use the demuxer timebase.
1472 The time base is copied to the output encoder from the corresponding input
1473 demuxer. This is sometimes required to avoid non monotonically increasing
1474 timestamps when copying video streams with variable frame rate.
1477 Use the decoder timebase.
1479 The time base is copied to the output encoder from the corresponding input
1483 Try to make the choice automatically, in order to generate a sane output.
1486 Default value is -1.
1488 @item -enc_time_base[:@var{stream_specifier}] @var{timebase} (@emph{output,per-stream})
1489 Set the encoder timebase. @var{timebase} is a floating point number,
1490 and can assume one of the following values:
1494 Assign a default value according to the media type.
1496 For video - use 1/framerate, for audio - use 1/samplerate.
1499 Use the input stream timebase when possible.
1501 If an input stream is not available, the default timebase will be used.
1504 Use the provided number as the timebase.
1506 This field can be provided as a ratio of two integers (e.g. 1:24, 1:48000)
1507 or as a floating point number (e.g. 0.04166, 2.0833e-5)
1512 @item -bitexact (@emph{input/output})
1513 Enable bitexact mode for (de)muxer and (de/en)coder
1514 @item -shortest (@emph{output})
1515 Finish encoding when the shortest input stream ends.
1516 @item -dts_delta_threshold
1517 Timestamp discontinuity delta threshold.
1518 @item -dts_error_threshold @var{seconds}
1519 Timestamp error delta threshold. This threshold use to discard crazy/damaged
1520 timestamps and the default is 30 hours which is arbitrarily picked and quite
1522 @item -muxdelay @var{seconds} (@emph{output})
1523 Set the maximum demux-decode delay.
1524 @item -muxpreload @var{seconds} (@emph{output})
1525 Set the initial demux-decode delay.
1526 @item -streamid @var{output-stream-index}:@var{new-value} (@emph{output})
1527 Assign a new stream-id value to an output stream. This option should be
1528 specified prior to the output filename to which it applies.
1529 For the situation where multiple output files exist, a streamid
1530 may be reassigned to a different value.
1532 For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for
1533 an output mpegts file:
1535 ffmpeg -i inurl -streamid 0:33 -streamid 1:36 out.ts
1538 @item -bsf[:@var{stream_specifier}] @var{bitstream_filters} (@emph{output,per-stream})
1539 Set bitstream filters for matching streams. @var{bitstream_filters} is
1540 a comma-separated list of bitstream filters. Use the @code{-bsfs} option
1541 to get the list of bitstream filters.
1543 ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264
1546 ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt
1549 @item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{input/output,per-stream})
1550 Force a tag/fourcc for matching streams.
1552 @item -timecode @var{hh}:@var{mm}:@var{ss}SEP@var{ff}
1553 Specify Timecode for writing. @var{SEP} is ':' for non drop timecode and ';'
1556 ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg
1559 @anchor{filter_complex_option}
1560 @item -filter_complex @var{filtergraph} (@emph{global})
1561 Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
1562 outputs. For simple graphs -- those with one input and one output of the same
1563 type -- see the @option{-filter} options. @var{filtergraph} is a description of
1564 the filtergraph, as described in the ``Filtergraph syntax'' section of the
1565 ffmpeg-filters manual.
1567 Input link labels must refer to input streams using the
1568 @code{[file_index:stream_specifier]} syntax (i.e. the same as @option{-map}
1569 uses). If @var{stream_specifier} matches multiple streams, the first one will be
1570 used. An unlabeled input will be connected to the first unused input stream of
1573 Output link labels are referred to with @option{-map}. Unlabeled outputs are
1574 added to the first output file.
1576 Note that with this option it is possible to use only lavfi sources without
1579 For example, to overlay an image over video
1581 ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
1584 Here @code{[0:v]} refers to the first video stream in the first input file,
1585 which is linked to the first (main) input of the overlay filter. Similarly the
1586 first video stream in the second input is linked to the second (overlay) input
1589 Assuming there is only one video stream in each input file, we can omit input
1590 labels, so the above is equivalent to
1592 ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map
1596 Furthermore we can omit the output label and the single output from the filter
1597 graph will be added to the output file automatically, so we can simply write
1599 ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv
1602 To generate 5 seconds of pure red video using lavfi @code{color} source:
1604 ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv
1607 @item -filter_complex_threads @var{nb_threads} (@emph{global})
1608 Defines how many threads are used to process a filter_complex graph.
1609 Similar to filter_threads but used for @code{-filter_complex} graphs only.
1610 The default is the number of available CPUs.
1612 @item -lavfi @var{filtergraph} (@emph{global})
1613 Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
1614 outputs. Equivalent to @option{-filter_complex}.
1616 @item -filter_complex_script @var{filename} (@emph{global})
1617 This option is similar to @option{-filter_complex}, the only difference is that
1618 its argument is the name of the file from which a complex filtergraph
1619 description is to be read.
1621 @item -accurate_seek (@emph{input})
1622 This option enables or disables accurate seeking in input files with the
1623 @option{-ss} option. It is enabled by default, so seeking is accurate when
1624 transcoding. Use @option{-noaccurate_seek} to disable it, which may be useful
1625 e.g. when copying some streams and transcoding the others.
1627 @item -seek_timestamp (@emph{input})
1628 This option enables or disables seeking by timestamp in input files with the
1629 @option{-ss} option. It is disabled by default. If enabled, the argument
1630 to the @option{-ss} option is considered an actual timestamp, and is not
1631 offset by the start time of the file. This matters only for files which do
1632 not start from timestamp 0, such as transport streams.
1634 @item -thread_queue_size @var{size} (@emph{input})
1635 This option sets the maximum number of queued packets when reading from the
1636 file or device. With low latency / high rate live streams, packets may be
1637 discarded if they are not read in a timely manner; raising this value can
1640 @item -sdp_file @var{file} (@emph{global})
1641 Print sdp information for an output stream to @var{file}.
1642 This allows dumping sdp information when at least one output isn't an
1643 rtp stream. (Requires at least one of the output formats to be rtp).
1645 @item -discard (@emph{input})
1646 Allows discarding specific streams or frames from streams.
1647 Any input stream can be fully discarded, using value @code{all} whereas
1648 selective discarding of frames from a stream occurs at the demuxer
1649 and is not supported by all demuxers.
1656 Default, which discards no frames.
1659 Discard all non-reference frames.
1662 Discard all bidirectional frames.
1665 Discard all frames excepts keyframes.
1671 @item -abort_on @var{flags} (@emph{global})
1672 Stop and abort on various conditions. The following flags are available:
1676 No packets were passed to the muxer, the output is empty.
1679 @item -xerror (@emph{global})
1680 Stop and exit on error
1682 @item -max_muxing_queue_size @var{packets} (@emph{output,per-stream})
1683 When transcoding audio and/or video streams, ffmpeg will not begin writing into
1684 the output until it has one packet for each such stream. While waiting for that
1685 to happen, packets for other streams are buffered. This option sets the size of
1686 this buffer, in packets, for the matching output stream.
1688 The default value of this option should be high enough for most uses, so only
1689 touch this option if you are sure that you need it.
1693 As a special exception, you can use a bitmap subtitle stream as input: it
1694 will be converted into a video with the same size as the largest video in
1695 the file, or 720x576 if no video is present. Note that this is an
1696 experimental and temporary solution. It will be removed once libavfilter has
1697 proper support for subtitles.
1699 For example, to hardcode subtitles on top of a DVB-T recording stored in
1700 MPEG-TS format, delaying the subtitles by 1 second:
1702 ffmpeg -i input.ts -filter_complex \
1703 '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
1704 -sn -map '#0x2dc' output.mkv
1706 (0x2d0, 0x2dc and 0x2ef are the MPEG-TS PIDs of respectively the video,
1707 audio and subtitles streams; 0:0, 0:3 and 0:7 would have worked too)
1709 @section Preset files
1710 A preset file contains a sequence of @var{option}=@var{value} pairs,
1711 one for each line, specifying a sequence of options which would be
1712 awkward to specify on the command line. Lines starting with the hash
1713 ('#') character are ignored and are used to provide comments. Check
1714 the @file{presets} directory in the FFmpeg source tree for examples.
1716 There are two types of preset files: ffpreset and avpreset files.
1718 @subsection ffpreset files
1719 ffpreset files are specified with the @code{vpre}, @code{apre},
1720 @code{spre}, and @code{fpre} options. The @code{fpre} option takes the
1721 filename of the preset instead of a preset name as input and can be
1722 used for any kind of codec. For the @code{vpre}, @code{apre}, and
1723 @code{spre} options, the options specified in a preset file are
1724 applied to the currently selected codec of the same type as the preset
1727 The argument passed to the @code{vpre}, @code{apre}, and @code{spre}
1728 preset options identifies the preset file to use according to the
1731 First ffmpeg searches for a file named @var{arg}.ffpreset in the
1732 directories @file{$FFMPEG_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
1733 the datadir defined at configuration time (usually @file{PREFIX/share/ffmpeg})
1734 or in a @file{ffpresets} folder along the executable on win32,
1735 in that order. For example, if the argument is @code{libvpx-1080p}, it will
1736 search for the file @file{libvpx-1080p.ffpreset}.
1738 If no such file is found, then ffmpeg will search for a file named
1739 @var{codec_name}-@var{arg}.ffpreset in the above-mentioned
1740 directories, where @var{codec_name} is the name of the codec to which
1741 the preset file options will be applied. For example, if you select
1742 the video codec with @code{-vcodec libvpx} and use @code{-vpre 1080p},
1743 then it will search for the file @file{libvpx-1080p.ffpreset}.
1745 @subsection avpreset files
1746 avpreset files are specified with the @code{pre} option. They work similar to
1747 ffpreset files, but they only allow encoder- specific options. Therefore, an
1748 @var{option}=@var{value} pair specifying an encoder cannot be used.
1750 When the @code{pre} option is specified, ffmpeg will look for files with the
1751 suffix .avpreset in the directories @file{$AVCONV_DATADIR} (if set), and
1752 @file{$HOME/.avconv}, and in the datadir defined at configuration time (usually
1753 @file{PREFIX/share/ffmpeg}), in that order.
1755 First ffmpeg searches for a file named @var{codec_name}-@var{arg}.avpreset in
1756 the above-mentioned directories, where @var{codec_name} is the name of the codec
1757 to which the preset file options will be applied. For example, if you select the
1758 video codec with @code{-vcodec libvpx} and use @code{-pre 1080p}, then it will
1759 search for the file @file{libvpx-1080p.avpreset}.
1761 If no such file is found, then ffmpeg will search for a file named
1762 @var{arg}.avpreset in the same directories.
1767 @c man begin EXAMPLES
1769 @section Video and Audio grabbing
1771 If you specify the input format and device then ffmpeg can grab video
1775 ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
1778 Or with an ALSA audio source (mono input, card id 1) instead of OSS:
1780 ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg
1783 Note that you must activate the right video source and channel before
1784 launching ffmpeg with any TV viewer such as
1785 @uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also
1786 have to set the audio recording levels correctly with a
1789 @section X11 grabbing
1791 Grab the X11 display with ffmpeg via
1794 ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0 /tmp/out.mpg
1797 0.0 is display.screen number of your X11 server, same as
1798 the DISPLAY environment variable.
1801 ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0+10,20 /tmp/out.mpg
1804 0.0 is display.screen number of your X11 server, same as the DISPLAY environment
1805 variable. 10 is the x-offset and 20 the y-offset for the grabbing.
1807 @section Video and Audio file format conversion
1809 Any supported file format and protocol can serve as input to ffmpeg:
1814 You can use YUV files as input:
1817 ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
1820 It will use the files:
1822 /tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
1823 /tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
1826 The Y files use twice the resolution of the U and V files. They are
1827 raw files, without header. They can be generated by all decent video
1828 decoders. You must specify the size of the image with the @option{-s} option
1829 if ffmpeg cannot guess it.
1832 You can input from a raw YUV420P file:
1835 ffmpeg -i /tmp/test.yuv /tmp/out.avi
1838 test.yuv is a file containing raw YUV planar data. Each frame is composed
1839 of the Y plane followed by the U and V planes at half vertical and
1840 horizontal resolution.
1843 You can output to a raw YUV420P file:
1846 ffmpeg -i mydivx.avi hugefile.yuv
1850 You can set several input files and output files:
1853 ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
1856 Converts the audio file a.wav and the raw YUV video file a.yuv
1860 You can also do audio and video conversions at the same time:
1863 ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
1866 Converts a.wav to MPEG audio at 22050 Hz sample rate.
1869 You can encode to several formats at the same time and define a
1870 mapping from input stream to output streams:
1873 ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2
1876 Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
1877 file:index' specifies which input stream is used for each output
1878 stream, in the order of the definition of output streams.
1881 You can transcode decrypted VOBs:
1884 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
1887 This is a typical DVD ripping example; the input is a VOB file, the
1888 output an AVI file with MPEG-4 video and MP3 audio. Note that in this
1889 command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
1890 GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
1891 input video. Furthermore, the audio stream is MP3-encoded so you need
1892 to enable LAME support by passing @code{--enable-libmp3lame} to configure.
1893 The mapping is particularly useful for DVD transcoding
1894 to get the desired audio language.
1896 NOTE: To see the supported input formats, use @code{ffmpeg -demuxers}.
1899 You can extract images from a video, or create a video from many images:
1901 For extracting images from a video:
1903 ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
1906 This will extract one video frame per second from the video and will
1907 output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg},
1908 etc. Images will be rescaled to fit the new WxH values.
1910 If you want to extract just a limited number of frames, you can use the
1911 above command in combination with the @code{-frames:v} or @code{-t} option,
1912 or in combination with -ss to start extracting from a certain point in time.
1914 For creating a video from many images:
1916 ffmpeg -f image2 -framerate 12 -i foo-%03d.jpeg -s WxH foo.avi
1919 The syntax @code{foo-%03d.jpeg} specifies to use a decimal number
1920 composed of three digits padded with zeroes to express the sequence
1921 number. It is the same syntax supported by the C printf function, but
1922 only formats accepting a normal integer are suitable.
1924 When importing an image sequence, -i also supports expanding
1925 shell-like wildcard patterns (globbing) internally, by selecting the
1926 image2-specific @code{-pattern_type glob} option.
1928 For example, for creating a video from filenames matching the glob pattern
1931 ffmpeg -f image2 -pattern_type glob -framerate 12 -i 'foo-*.jpeg' -s WxH foo.avi
1935 You can put many streams of the same type in the output:
1938 ffmpeg -i test1.avi -i test2.avi -map 1:1 -map 1:0 -map 0:1 -map 0:0 -c copy -y test12.nut
1941 The resulting output file @file{test12.nut} will contain the first four streams
1942 from the input files in reverse order.
1945 To force CBR video output:
1947 ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
1951 The four options lmin, lmax, mblmin and mblmax use 'lambda' units,
1952 but you may use the QP2LAMBDA constant to easily convert from 'q' units:
1954 ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
1960 @include config.texi
1962 @ifset config-avutil
1965 @ifset config-avcodec
1966 @include codecs.texi
1967 @include bitstream_filters.texi
1969 @ifset config-avformat
1970 @include formats.texi
1971 @include protocols.texi
1973 @ifset config-avdevice
1974 @include devices.texi
1976 @ifset config-swresample
1977 @include resampler.texi
1979 @ifset config-swscale
1980 @include scaler.texi
1982 @ifset config-avfilter
1983 @include filters.texi
1991 @url{ffmpeg.html,ffmpeg}
1993 @ifset config-not-all
1994 @url{ffmpeg-all.html,ffmpeg-all},
1996 @url{ffplay.html,ffplay}, @url{ffprobe.html,ffprobe},
1997 @url{ffmpeg-utils.html,ffmpeg-utils},
1998 @url{ffmpeg-scaler.html,ffmpeg-scaler},
1999 @url{ffmpeg-resampler.html,ffmpeg-resampler},
2000 @url{ffmpeg-codecs.html,ffmpeg-codecs},
2001 @url{ffmpeg-bitstream-filters.html,ffmpeg-bitstream-filters},
2002 @url{ffmpeg-formats.html,ffmpeg-formats},
2003 @url{ffmpeg-devices.html,ffmpeg-devices},
2004 @url{ffmpeg-protocols.html,ffmpeg-protocols},
2005 @url{ffmpeg-filters.html,ffmpeg-filters}
2012 @ifset config-not-all
2015 ffplay(1), ffprobe(1),
2016 ffmpeg-utils(1), ffmpeg-scaler(1), ffmpeg-resampler(1),
2017 ffmpeg-codecs(1), ffmpeg-bitstream-filters(1), ffmpeg-formats(1),
2018 ffmpeg-devices(1), ffmpeg-protocols(1), ffmpeg-filters(1)
2021 @include authors.texi
2026 @settitle ffmpeg video converter