1 \input texinfo @c -*- texinfo -*-
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4 @settitle ffmpeg Documentation
6 @center @titlefont{ffmpeg Documentation}
15 ffmpeg [@var{global_options}] @{[@var{input_file_options}] -i @file{input_file}@} ... @{[@var{output_file_options}] @file{output_file}@} ...
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 filename. Anything found on the command line which
28 cannot be interpreted as an option is considered to be an output filename.
30 Each input or output file 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 By default, @command{ffmpeg} includes only one stream of each type (video, audio, subtitle)
220 present in the input files and adds them to each output file. It picks the
221 "best" of each based upon the following criteria: for video, it is the stream
222 with the highest resolution, for audio, it is the stream with the most channels, for
223 subtitles, it is the first subtitle stream. In the case where several streams of
224 the same type rate equally, the stream with the lowest index is chosen.
226 You can disable some of those defaults by using the @code{-vn/-an/-sn} options. For
227 full manual control, use the @code{-map} option, which disables the defaults just
230 @c man end STREAM SELECTION
235 @include fftools-common-opts.texi
237 @section Main options
241 @item -f @var{fmt} (@emph{input/output})
242 Force input or output file format. The format is normally auto detected for input
243 files and guessed from the file extension for output files, so this option is not
244 needed in most cases.
246 @item -i @var{filename} (@emph{input})
249 @item -y (@emph{global})
250 Overwrite output files without asking.
252 @item -n (@emph{global})
253 Do not overwrite output files, and exit immediately if a specified
254 output file already exists.
256 @item -c[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
257 @itemx -codec[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
258 Select an encoder (when used before an output file) or a decoder (when used
259 before an input file) for one or more streams. @var{codec} is the name of a
260 decoder/encoder or a special value @code{copy} (output only) to indicate that
261 the stream is not to be re-encoded.
265 ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT
267 encodes all video streams with libx264 and copies all audio streams.
269 For each stream, the last matching @code{c} option is applied, so
271 ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT
273 will copy all the streams except the second video, which will be encoded with
274 libx264, and the 138th audio, which will be encoded with libvorbis.
276 @item -t @var{duration} (@emph{input/output})
277 When used as an input option (before @code{-i}), limit the @var{duration} of
278 data read from the input file.
280 When used as an output option (before an output filename), stop writing the
281 output after its duration reaches @var{duration}.
283 @var{duration} may be a number in seconds, or in @code{hh:mm:ss[.xxx]} form.
285 -to and -t are mutually exclusive and -t has priority.
287 @item -to @var{position} (@emph{output})
288 Stop writing the output at @var{position}.
289 @var{position} may be a number in seconds, or in @code{hh:mm:ss[.xxx]} form.
291 -to and -t are mutually exclusive and -t has priority.
293 @item -fs @var{limit_size} (@emph{output})
294 Set the file size limit, expressed in bytes.
296 @item -ss @var{position} (@emph{input/output})
297 When used as an input option (before @code{-i}), seeks in this input file to
298 @var{position}. Note the in most formats it is not possible to seek exactly, so
299 @command{ffmpeg} will seek to the closest seek point before @var{position}.
300 When transcoding and @option{-accurate_seek} is enabled (the default), this
301 extra segment between the seek point and @var{position} will be decoded and
302 discarded. When doing stream copy or when @option{-noaccurate_seek} is used, it
305 When used as an output option (before an output filename), decodes but discards
306 input until the timestamps reach @var{position}.
308 @var{position} may be either in seconds or in @code{hh:mm:ss[.xxx]} form.
310 @item -itsoffset @var{offset} (@emph{input})
311 Set the input time offset.
313 @var{offset} must be a time duration specification,
314 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
316 The offset is added to the timestamps of the input files. Specifying
317 a positive offset means that the corresponding streams are delayed by
318 the time duration specified in @var{offset}.
320 @item -timestamp @var{date} (@emph{output})
321 Set the recording timestamp in the container.
323 @var{date} must be a time duration specification,
324 see @ref{date syntax,,the Date section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
326 @item -metadata[:metadata_specifier] @var{key}=@var{value} (@emph{output,per-metadata})
327 Set a metadata key/value pair.
329 An optional @var{metadata_specifier} may be given to set metadata
330 on streams or chapters. See @code{-map_metadata} documentation for
333 This option overrides metadata set with @code{-map_metadata}. It is
334 also possible to delete metadata by using an empty value.
336 For example, for setting the title in the output file:
338 ffmpeg -i in.avi -metadata title="my title" out.flv
341 To set the language of the first audio stream:
343 ffmpeg -i INPUT -metadata:s:a:0 language=eng OUTPUT
346 @item -target @var{type} (@emph{output})
347 Specify target file type (@code{vcd}, @code{svcd}, @code{dvd}, @code{dv},
348 @code{dv50}). @var{type} may be prefixed with @code{pal-}, @code{ntsc-} or
349 @code{film-} to use the corresponding standard. All the format options
350 (bitrate, codecs, buffer sizes) are then set automatically. You can just type:
353 ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
356 Nevertheless you can specify additional options as long as you know
357 they do not conflict with the standard, as in:
360 ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
363 @item -dframes @var{number} (@emph{output})
364 Set the number of data frames to output. This is an alias for @code{-frames:d}.
366 @item -frames[:@var{stream_specifier}] @var{framecount} (@emph{output,per-stream})
367 Stop writing to the stream after @var{framecount} frames.
369 @item -q[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
370 @itemx -qscale[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
371 Use fixed quality scale (VBR). The meaning of @var{q}/@var{qscale} is
373 If @var{qscale} is used without a @var{stream_specifier} then it applies only
374 to the video stream, this is to maintain compatibility with previous behavior
375 and as specifying the same codec specific value to 2 different codecs that is
376 audio and video generally is not what is intended when no stream_specifier is
379 @anchor{filter_option}
380 @item -filter[:@var{stream_specifier}] @var{filtergraph} (@emph{output,per-stream})
381 Create the filtergraph specified by @var{filtergraph} and use it to
384 @var{filtergraph} is a description of the filtergraph to apply to
385 the stream, and must have a single input and a single output of the
386 same type of the stream. In the filtergraph, the input is associated
387 to the label @code{in}, and the output to the label @code{out}. See
388 the ffmpeg-filters manual for more information about the filtergraph
391 See the @ref{filter_complex_option,,-filter_complex option} if you
392 want to create filtergraphs with multiple inputs and/or outputs.
394 @item -filter_script[:@var{stream_specifier}] @var{filename} (@emph{output,per-stream})
395 This option is similar to @option{-filter}, the only difference is that its
396 argument is the name of the file from which a filtergraph description is to be
399 @item -pre[:@var{stream_specifier}] @var{preset_name} (@emph{output,per-stream})
400 Specify the preset for matching stream(s).
402 @item -stats (@emph{global})
403 Print encoding progress/statistics. It is on by default, to explicitly
404 disable it you need to specify @code{-nostats}.
406 @item -progress @var{url} (@emph{global})
407 Send program-friendly progress information to @var{url}.
409 Progress information is written approximately every second and at the end of
410 the encoding process. It is made of "@var{key}=@var{value}" lines. @var{key}
411 consists of only alphanumeric characters. The last key of a sequence of
412 progress information is always "progress".
415 Enable interaction on standard input. On by default unless standard input is
416 used as an input. To explicitly disable interaction you need to specify
419 Disabling interaction on standard input is useful, for example, if
420 ffmpeg is in the background process group. Roughly the same result can
421 be achieved with @code{ffmpeg ... < /dev/null} but it requires a
424 @item -debug_ts (@emph{global})
425 Print timestamp information. It is off by default. This option is
426 mostly useful for testing and debugging purposes, and the output
427 format may change from one version to another, so it should not be
428 employed by portable scripts.
430 See also the option @code{-fdebug ts}.
432 @item -attach @var{filename} (@emph{output})
433 Add an attachment to the output file. This is supported by a few formats
434 like Matroska for e.g. fonts used in rendering subtitles. Attachments
435 are implemented as a specific type of stream, so this option will add
436 a new stream to the file. It is then possible to use per-stream options
437 on this stream in the usual way. Attachment streams created with this
438 option will be created after all the other streams (i.e. those created
439 with @code{-map} or automatic mappings).
441 Note that for Matroska you also have to set the mimetype metadata tag:
443 ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv
445 (assuming that the attachment stream will be third in the output file).
447 @item -dump_attachment[:@var{stream_specifier}] @var{filename} (@emph{input,per-stream})
448 Extract the matching attachment stream into a file named @var{filename}. If
449 @var{filename} is empty, then the value of the @code{filename} metadata tag
452 E.g. to extract the first attachment to a file named 'out.ttf':
454 ffmpeg -dump_attachment:t:0 out.ttf -i INPUT
456 To extract all attachments to files determined by the @code{filename} tag:
458 ffmpeg -dump_attachment:t "" -i INPUT
461 Technical note -- attachments are implemented as codec extradata, so this
462 option can actually be used to extract extradata from any stream, not just
466 Disable automatically rotating video based on file metadata.
470 @section Video Options
473 @item -vframes @var{number} (@emph{output})
474 Set the number of video frames to output. This is an alias for @code{-frames:v}.
475 @item -r[:@var{stream_specifier}] @var{fps} (@emph{input/output,per-stream})
476 Set frame rate (Hz value, fraction or abbreviation).
478 As an input option, ignore any timestamps stored in the file and instead
479 generate timestamps assuming constant frame rate @var{fps}.
480 This is not the same as the @option{-framerate} option used for some input formats
481 like image2 or v4l2 (it used to be the same in older versions of FFmpeg).
482 If in doubt use @option{-framerate} instead of the input option @option{-r}.
484 As an output option, duplicate or drop input frames to achieve constant output
485 frame rate @var{fps}.
487 @item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream})
490 As an input option, this is a shortcut for the @option{video_size} private
491 option, recognized by some demuxers for which the frame size is either not
492 stored in the file or is configurable -- e.g. raw video or video grabbers.
494 As an output option, this inserts the @code{scale} video filter to the
495 @emph{end} of the corresponding filtergraph. Please use the @code{scale} filter
496 directly to insert it at the beginning or some other place.
498 The format is @samp{wxh} (default - same as source).
500 @item -aspect[:@var{stream_specifier}] @var{aspect} (@emph{output,per-stream})
501 Set the video display aspect ratio specified by @var{aspect}.
503 @var{aspect} can be a floating point number string, or a string of the
504 form @var{num}:@var{den}, where @var{num} and @var{den} are the
505 numerator and denominator of the aspect ratio. For example "4:3",
506 "16:9", "1.3333", and "1.7777" are valid argument values.
508 If used together with @option{-vcodec copy}, it will affect the aspect ratio
509 stored at container level, but not the aspect ratio stored in encoded
510 frames, if it exists.
512 @item -vn (@emph{output})
513 Disable video recording.
515 @item -vcodec @var{codec} (@emph{output})
516 Set the video codec. This is an alias for @code{-codec:v}.
518 @item -pass[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
519 Select the pass number (1 or 2). It is used to do two-pass
520 video encoding. The statistics of the video are recorded in the first
521 pass into a log file (see also the option -passlogfile),
522 and in the second pass that log file is used to generate the video
523 at the exact requested bitrate.
524 On pass 1, you may just deactivate audio and set output to null,
525 examples for Windows and Unix:
527 ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
528 ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null
531 @item -passlogfile[:@var{stream_specifier}] @var{prefix} (@emph{output,per-stream})
532 Set two-pass log file name prefix to @var{prefix}, the default file name
533 prefix is ``ffmpeg2pass''. The complete file name will be
534 @file{PREFIX-N.log}, where N is a number specific to the output
537 @item -vf @var{filtergraph} (@emph{output})
538 Create the filtergraph specified by @var{filtergraph} and use it to
541 This is an alias for @code{-filter:v}, see the @ref{filter_option,,-filter option}.
544 @section Advanced Video options
547 @item -pix_fmt[:@var{stream_specifier}] @var{format} (@emph{input/output,per-stream})
548 Set pixel format. Use @code{-pix_fmts} to show all the supported
550 If the selected pixel format can not be selected, ffmpeg will print a
551 warning and select the best pixel format supported by the encoder.
552 If @var{pix_fmt} is prefixed by a @code{+}, ffmpeg will exit with an error
553 if the requested pixel format can not be selected, and automatic conversions
554 inside filtergraphs are disabled.
555 If @var{pix_fmt} is a single @code{+}, ffmpeg selects the same pixel format
556 as the input (or graph output) and automatic conversions are disabled.
558 @item -sws_flags @var{flags} (@emph{input/output})
563 @item -rc_override[:@var{stream_specifier}] @var{override} (@emph{output,per-stream})
564 Rate control override for specific intervals, formatted as "int,int,int"
565 list separated with slashes. Two first values are the beginning and
566 end frame numbers, last one is quantizer to use if positive, or quality
570 Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
571 Use this option if your input file is interlaced and you want
572 to keep the interlaced format for minimum losses.
573 The alternative is to deinterlace the input stream with
574 @option{-deinterlace}, but deinterlacing introduces losses.
576 Calculate PSNR of compressed frames.
578 Dump video coding statistics to @file{vstats_HHMMSS.log}.
579 @item -vstats_file @var{file}
580 Dump video coding statistics to @var{file}.
581 @item -top[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
582 top=1/bottom=0/auto=-1 field first
583 @item -dc @var{precision}
585 @item -vtag @var{fourcc/tag} (@emph{output})
586 Force video tag/fourcc. This is an alias for @code{-tag:v}.
587 @item -qphist (@emph{global})
589 @item -vbsf @var{bitstream_filter}
592 @item -force_key_frames[:@var{stream_specifier}] @var{time}[,@var{time}...] (@emph{output,per-stream})
593 @item -force_key_frames[:@var{stream_specifier}] expr:@var{expr} (@emph{output,per-stream})
594 Force key frames at the specified timestamps, more precisely at the first
595 frames after each specified time.
597 If the argument is prefixed with @code{expr:}, the string @var{expr}
598 is interpreted like an expression and is evaluated for each frame. A
599 key frame is forced in case the evaluation is non-zero.
601 If one of the times is "@code{chapters}[@var{delta}]", it is expanded into
602 the time of the beginning of all chapters in the file, shifted by
603 @var{delta}, expressed as a time in seconds.
604 This option can be useful to ensure that a seek point is present at a
605 chapter mark or any other designated place in the output file.
607 For example, to insert a key frame at 5 minutes, plus key frames 0.1 second
608 before the beginning of every chapter:
610 -force_key_frames 0:05:00,chapters-0.1
613 The expression in @var{expr} can contain the following constants:
616 the number of current processed frame, starting from 0
618 the number of forced frames
620 the number of the previous forced frame, it is @code{NAN} when no
621 keyframe was forced yet
623 the time of the previous forced frame, it is @code{NAN} when no
624 keyframe was forced yet
626 the time of the current processed frame
629 For example to force a key frame every 5 seconds, you can specify:
631 -force_key_frames expr:gte(t,n_forced*5)
634 To force a key frame 5 seconds after the time of the last forced one,
635 starting from second 13:
637 -force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5))
640 Note that forcing too many keyframes is very harmful for the lookahead
641 algorithms of certain encoders: using fixed-GOP options or similar
642 would be more efficient.
644 @item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream})
645 When doing stream copy, copy also non-key frames found at the
648 @item -hwaccel[:@var{stream_specifier}] @var{hwaccel} (@emph{input,per-stream})
649 Use hardware acceleration to decode the matching stream(s). The allowed values
650 of @var{hwaccel} are:
653 Do not use any hardware acceleration (the default).
656 Automatically select the hardware acceleration method.
659 Use Apple VDA hardware acceleration.
662 Use VDPAU (Video Decode and Presentation API for Unix) hardware acceleration.
665 Use DXVA2 (DirectX Video Acceleration) hardware acceleration.
668 This option has no effect if the selected hwaccel is not available or not
669 supported by the chosen decoder.
671 Note that most acceleration methods are intended for playback and will not be
672 faster than software decoding on modern CPUs. Additionally, @command{ffmpeg}
673 will usually need to copy the decoded frames from the GPU memory into the system
674 memory, resulting in further performance loss. This option is thus mainly
677 @item -hwaccel_device[:@var{stream_specifier}] @var{hwaccel_device} (@emph{input,per-stream})
678 Select a device to use for hardware acceleration.
680 This option only makes sense when the @option{-hwaccel} option is also
681 specified. Its exact meaning depends on the specific hardware acceleration
686 For VDPAU, this option specifies the X11 display/screen to use. If this option
687 is not specified, the value of the @var{DISPLAY} environment variable is used
690 For DXVA2, this option should contain the number of the display adapter to use.
691 If this option is not specified, the default adapter is used.
695 @section Audio Options
698 @item -aframes @var{number} (@emph{output})
699 Set the number of audio frames to output. This is an alias for @code{-frames:a}.
700 @item -ar[:@var{stream_specifier}] @var{freq} (@emph{input/output,per-stream})
701 Set the audio sampling frequency. For output streams it is set by
702 default to the frequency of the corresponding input stream. For input
703 streams this option only makes sense for audio grabbing devices and raw
704 demuxers and is mapped to the corresponding demuxer options.
705 @item -aq @var{q} (@emph{output})
706 Set the audio quality (codec-specific, VBR). This is an alias for -q:a.
707 @item -ac[:@var{stream_specifier}] @var{channels} (@emph{input/output,per-stream})
708 Set the number of audio channels. For output streams it is set by
709 default to the number of input audio channels. For input streams
710 this option only makes sense for audio grabbing devices and raw demuxers
711 and is mapped to the corresponding demuxer options.
712 @item -an (@emph{output})
713 Disable audio recording.
714 @item -acodec @var{codec} (@emph{input/output})
715 Set the audio codec. This is an alias for @code{-codec:a}.
716 @item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream})
717 Set the audio sample format. Use @code{-sample_fmts} to get a list
718 of supported sample formats.
720 @item -af @var{filtergraph} (@emph{output})
721 Create the filtergraph specified by @var{filtergraph} and use it to
724 This is an alias for @code{-filter:a}, see the @ref{filter_option,,-filter option}.
727 @section Advanced Audio options
730 @item -atag @var{fourcc/tag} (@emph{output})
731 Force audio tag/fourcc. This is an alias for @code{-tag:a}.
732 @item -absf @var{bitstream_filter}
734 @item -guess_layout_max @var{channels} (@emph{input,per-stream})
735 If some input channel layout is not known, try to guess only if it
736 corresponds to at most the specified number of channels. For example, 2
737 tells to @command{ffmpeg} to recognize 1 channel as mono and 2 channels as
738 stereo but not 6 channels as 5.1. The default is to always try to guess. Use
739 0 to disable all guessing.
742 @section Subtitle options
745 @item -scodec @var{codec} (@emph{input/output})
746 Set the subtitle codec. This is an alias for @code{-codec:s}.
747 @item -sn (@emph{output})
748 Disable subtitle recording.
749 @item -sbsf @var{bitstream_filter}
753 @section Advanced Subtitle options
757 @item -fix_sub_duration
758 Fix subtitles durations. For each subtitle, wait for the next packet in the
759 same stream and adjust the duration of the first to avoid overlap. This is
760 necessary with some subtitles codecs, especially DVB subtitles, because the
761 duration in the original packet is only a rough estimate and the end is
762 actually marked by an empty subtitle frame. Failing to use this option when
763 necessary can result in exaggerated durations or muxing failures due to
764 non-monotonic timestamps.
766 Note that this option will delay the output of all data until the next
767 subtitle packet is decoded: it may increase memory consumption and latency a
770 @item -canvas_size @var{size}
771 Set the size of the canvas used to render subtitles.
775 @section Advanced options
778 @item -map [-]@var{input_file_id}[:@var{stream_specifier}][,@var{sync_file_id}[:@var{stream_specifier}]] | @var{[linklabel]} (@emph{output})
780 Designate one or more input streams as a source for the output file. Each input
781 stream is identified by the input file index @var{input_file_id} and
782 the input stream index @var{input_stream_id} within the input
783 file. Both indices start at 0. If specified,
784 @var{sync_file_id}:@var{stream_specifier} sets which input stream
785 is used as a presentation sync reference.
787 The first @code{-map} option on the command line specifies the
788 source for output stream 0, the second @code{-map} option specifies
789 the source for output stream 1, etc.
791 A @code{-} character before the stream identifier creates a "negative" mapping.
792 It disables matching streams from already created mappings.
794 An alternative @var{[linklabel]} form will map outputs from complex filter
795 graphs (see the @option{-filter_complex} option) to the output file.
796 @var{linklabel} must correspond to a defined output link label in the graph.
798 For example, to map ALL streams from the first input file to output
800 ffmpeg -i INPUT -map 0 output
803 For example, if you have two audio streams in the first input file,
804 these streams are identified by "0:0" and "0:1". You can use
805 @code{-map} to select which streams to place in an output file. For
808 ffmpeg -i INPUT -map 0:1 out.wav
810 will map the input stream in @file{INPUT} identified by "0:1" to
811 the (single) output stream in @file{out.wav}.
813 For example, to select the stream with index 2 from input file
814 @file{a.mov} (specified by the identifier "0:2"), and stream with
815 index 6 from input @file{b.mov} (specified by the identifier "1:6"),
816 and copy them to the output file @file{out.mov}:
818 ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
821 To select all video and the third audio stream from an input file:
823 ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT
826 To map all the streams except the second audio, use negative mappings
828 ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT
831 To pick the English audio stream:
833 ffmpeg -i INPUT -map 0:m:language:eng OUTPUT
836 Note that using this option disables the default mappings for this output file.
838 @item -map_channel [@var{input_file_id}.@var{stream_specifier}.@var{channel_id}|-1][:@var{output_file_id}.@var{stream_specifier}]
839 Map an audio channel from a given input to an output. If
840 @var{output_file_id}.@var{stream_specifier} is not set, the audio channel will
841 be mapped on all the audio streams.
843 Using "-1" instead of
844 @var{input_file_id}.@var{stream_specifier}.@var{channel_id} will map a muted
847 For example, assuming @var{INPUT} is a stereo audio file, you can switch the
848 two audio channels with the following command:
850 ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT
853 If you want to mute the first channel and keep the second:
855 ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT
858 The order of the "-map_channel" option specifies the order of the channels in
859 the output stream. The output channel layout is guessed from the number of
860 channels mapped (mono if one "-map_channel", stereo if two, etc.). Using "-ac"
861 in combination of "-map_channel" makes the channel gain levels to be updated if
862 input and output channel layouts don't match (for instance two "-map_channel"
863 options and "-ac 6").
865 You can also extract each channel of an input to specific outputs; the following
866 command extracts two channels of the @var{INPUT} audio stream (file 0, stream 0)
867 to the respective @var{OUTPUT_CH0} and @var{OUTPUT_CH1} outputs:
869 ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1
872 The following example splits the channels of a stereo input into two separate
873 streams, which are put into the same output file:
875 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
878 Note that currently each output stream can only contain channels from a single
879 input stream; you can't for example use "-map_channel" to pick multiple input
880 audio channels contained in different streams (from the same or different files)
881 and merge them into a single output stream. It is therefore not currently
882 possible, for example, to turn two separate mono streams into a single stereo
883 stream. However splitting a stereo stream into two single channel mono streams
886 If you need this feature, a possible workaround is to use the @emph{amerge}
887 filter. For example, if you need to merge a media (here @file{input.mkv}) with 2
888 mono audio streams into one single stereo channel audio stream (and keep the
889 video stream), you can use the following command:
891 ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv
894 @item -map_metadata[:@var{metadata_spec_out}] @var{infile}[:@var{metadata_spec_in}] (@emph{output,per-metadata})
895 Set metadata information of the next output file from @var{infile}. Note that
896 those are file indices (zero-based), not filenames.
897 Optional @var{metadata_spec_in/out} parameters specify, which metadata to copy.
898 A metadata specifier can have the following forms:
901 global metadata, i.e. metadata that applies to the whole file
903 @item @var{s}[:@var{stream_spec}]
904 per-stream metadata. @var{stream_spec} is a stream specifier as described
905 in the @ref{Stream specifiers} chapter. In an input metadata specifier, the first
906 matching stream is copied from. In an output metadata specifier, all matching
907 streams are copied to.
909 @item @var{c}:@var{chapter_index}
910 per-chapter metadata. @var{chapter_index} is the zero-based chapter index.
912 @item @var{p}:@var{program_index}
913 per-program metadata. @var{program_index} is the zero-based program index.
915 If metadata specifier is omitted, it defaults to global.
917 By default, global metadata is copied from the first input file,
918 per-stream and per-chapter metadata is copied along with streams/chapters. These
919 default mappings are disabled by creating any mapping of the relevant type. A negative
920 file index can be used to create a dummy mapping that just disables automatic copying.
922 For example to copy metadata from the first stream of the input file to global metadata
925 ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3
928 To do the reverse, i.e. copy global metadata to all audio streams:
930 ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv
932 Note that simple @code{0} would work as well in this example, since global
933 metadata is assumed by default.
935 @item -map_chapters @var{input_file_index} (@emph{output})
936 Copy chapters from input file with index @var{input_file_index} to the next
937 output file. If no chapter mapping is specified, then chapters are copied from
938 the first input file with at least one chapter. Use a negative file index to
939 disable any chapter copying.
941 @item -benchmark (@emph{global})
942 Show benchmarking information at the end of an encode.
943 Shows CPU time used and maximum memory consumption.
944 Maximum memory consumption is not supported on all systems,
945 it will usually display as 0 if not supported.
946 @item -benchmark_all (@emph{global})
947 Show benchmarking information during the encode.
948 Shows CPU time used in various steps (audio/video encode/decode).
949 @item -timelimit @var{duration} (@emph{global})
950 Exit after ffmpeg has been running for @var{duration} seconds.
951 @item -dump (@emph{global})
952 Dump each input packet to stderr.
953 @item -hex (@emph{global})
954 When dumping packets, also dump the payload.
955 @item -re (@emph{input})
956 Read input at native frame rate. Mainly used to simulate a grab device.
957 or live input stream (e.g. when reading from a file). Should not be used
958 with actual grab devices or live input streams (where it can cause packet
960 By default @command{ffmpeg} attempts to read the input(s) as fast as possible.
961 This option will slow down the reading of the input(s) to the native frame rate
962 of the input(s). It is useful for real-time output (e.g. live streaming).
964 Loop over the input stream. Currently it works only for image
965 streams. This option is used for automatic FFserver testing.
966 This option is deprecated, use -loop 1.
967 @item -loop_output @var{number_of_times}
968 Repeatedly loop output for formats that support looping such as animated GIF
969 (0 will loop the output infinitely).
970 This option is deprecated, use -loop.
971 @item -vsync @var{parameter}
973 For compatibility reasons old values can be specified as numbers.
974 Newly added values will have to be specified as strings always.
978 Each frame is passed with its timestamp from the demuxer to the muxer.
980 Frames will be duplicated and dropped to achieve exactly the requested
983 Frames are passed through with their timestamp or dropped so as to
984 prevent 2 frames from having the same timestamp.
986 As passthrough but destroys all timestamps, making the muxer generate
987 fresh timestamps based on frame-rate.
989 Chooses between 1 and 2 depending on muxer capabilities. This is the
993 Note that the timestamps may be further modified by the muxer, after this.
994 For example, in the case that the format option @option{avoid_negative_ts}
997 With -map you can select from which stream the timestamps should be
998 taken. You can leave either video or audio unchanged and sync the
999 remaining stream(s) to the unchanged one.
1001 @item -frame_drop_threshold @var{parameter}
1002 Frame drop threshold, which specifies how much behind video frames can
1003 be before they are dropped. In frame rate units, so 1.0 is one frame.
1004 The default is -1.1. One possible usecase is to avoid framedrops in case
1005 of noisy timestamps or to increase frame drop precision in case of exact
1008 @item -async @var{samples_per_second}
1009 Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
1010 the parameter is the maximum samples per second by which the audio is changed.
1011 -async 1 is a special case where only the start of the audio stream is corrected
1012 without any later correction.
1014 Note that the timestamps may be further modified by the muxer, after this.
1015 For example, in the case that the format option @option{avoid_negative_ts}
1018 This option has been deprecated. Use the @code{aresample} audio filter instead.
1021 Do not process input timestamps, but keep their values without trying
1022 to sanitize them. In particular, do not remove the initial start time
1025 Note that, depending on the @option{vsync} option or on specific muxer
1026 processing (e.g. in case the format option @option{avoid_negative_ts}
1027 is enabled) the output timestamps may mismatch with the input
1028 timestamps even when this option is selected.
1030 @item -start_at_zero
1031 When used with @option{copyts}, shift input timestamps so they start at zero.
1033 This means that using e.g. @code{-ss 50} will make output timestamps start at
1034 50 seconds, regardless of what timestamp the input file started at.
1036 @item -copytb @var{mode}
1037 Specify how to set the encoder timebase when stream copying. @var{mode} is an
1038 integer numeric value, and can assume one of the following values:
1042 Use the demuxer timebase.
1044 The time base is copied to the output encoder from the corresponding input
1045 demuxer. This is sometimes required to avoid non monotonically increasing
1046 timestamps when copying video streams with variable frame rate.
1049 Use the decoder timebase.
1051 The time base is copied to the output encoder from the corresponding input
1055 Try to make the choice automatically, in order to generate a sane output.
1058 Default value is -1.
1060 @item -shortest (@emph{output})
1061 Finish encoding when the shortest input stream ends.
1062 @item -dts_delta_threshold
1063 Timestamp discontinuity delta threshold.
1064 @item -muxdelay @var{seconds} (@emph{input})
1065 Set the maximum demux-decode delay.
1066 @item -muxpreload @var{seconds} (@emph{input})
1067 Set the initial demux-decode delay.
1068 @item -streamid @var{output-stream-index}:@var{new-value} (@emph{output})
1069 Assign a new stream-id value to an output stream. This option should be
1070 specified prior to the output filename to which it applies.
1071 For the situation where multiple output files exist, a streamid
1072 may be reassigned to a different value.
1074 For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for
1075 an output mpegts file:
1077 ffmpeg -i infile -streamid 0:33 -streamid 1:36 out.ts
1080 @item -bsf[:@var{stream_specifier}] @var{bitstream_filters} (@emph{output,per-stream})
1081 Set bitstream filters for matching streams. @var{bitstream_filters} is
1082 a comma-separated list of bitstream filters. Use the @code{-bsfs} option
1083 to get the list of bitstream filters.
1085 ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264
1088 ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt
1091 @item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{input/output,per-stream})
1092 Force a tag/fourcc for matching streams.
1094 @item -timecode @var{hh}:@var{mm}:@var{ss}SEP@var{ff}
1095 Specify Timecode for writing. @var{SEP} is ':' for non drop timecode and ';'
1098 ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg
1101 @anchor{filter_complex_option}
1102 @item -filter_complex @var{filtergraph} (@emph{global})
1103 Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
1104 outputs. For simple graphs -- those with one input and one output of the same
1105 type -- see the @option{-filter} options. @var{filtergraph} is a description of
1106 the filtergraph, as described in the ``Filtergraph syntax'' section of the
1107 ffmpeg-filters manual.
1109 Input link labels must refer to input streams using the
1110 @code{[file_index:stream_specifier]} syntax (i.e. the same as @option{-map}
1111 uses). If @var{stream_specifier} matches multiple streams, the first one will be
1112 used. An unlabeled input will be connected to the first unused input stream of
1115 Output link labels are referred to with @option{-map}. Unlabeled outputs are
1116 added to the first output file.
1118 Note that with this option it is possible to use only lavfi sources without
1121 For example, to overlay an image over video
1123 ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
1126 Here @code{[0:v]} refers to the first video stream in the first input file,
1127 which is linked to the first (main) input of the overlay filter. Similarly the
1128 first video stream in the second input is linked to the second (overlay) input
1131 Assuming there is only one video stream in each input file, we can omit input
1132 labels, so the above is equivalent to
1134 ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map
1138 Furthermore we can omit the output label and the single output from the filter
1139 graph will be added to the output file automatically, so we can simply write
1141 ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv
1144 To generate 5 seconds of pure red video using lavfi @code{color} source:
1146 ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv
1149 @item -lavfi @var{filtergraph} (@emph{global})
1150 Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
1151 outputs. Equivalent to @option{-filter_complex}.
1153 @item -filter_complex_script @var{filename} (@emph{global})
1154 This option is similar to @option{-filter_complex}, the only difference is that
1155 its argument is the name of the file from which a complex filtergraph
1156 description is to be read.
1158 @item -accurate_seek (@emph{input})
1159 This option enables or disables accurate seeking in input files with the
1160 @option{-ss} option. It is enabled by default, so seeking is accurate when
1161 transcoding. Use @option{-noaccurate_seek} to disable it, which may be useful
1162 e.g. when copying some streams and transcoding the others.
1164 @item -seek_timestamp (@emph{input})
1165 This option enables or disables seeking by timestamp in input files with the
1166 @option{-ss} option. It is disabled by default. If enabled, the argument
1167 to the @option{-ss} option is considered an actual timestamp, and is not
1168 offset by the start time of the file. This matters only for files which do
1169 not start from timestamp 0, such as transport streams.
1171 @item -thread_queue_size @var{size} (@emph{input})
1172 This option sets the maximum number of queued packets when reading from the
1173 file or device. With low latency / high rate live streams, packets may be
1174 discarded if they are not read in a timely manner; raising this value can
1177 @item -override_ffserver (@emph{global})
1178 Overrides the input specifications from @command{ffserver}. Using this
1179 option you can map any input stream to @command{ffserver} and control
1180 many aspects of the encoding from @command{ffmpeg}. Without this
1181 option @command{ffmpeg} will transmit to @command{ffserver} what is
1182 requested by @command{ffserver}.
1184 The option is intended for cases where features are needed that cannot be
1185 specified to @command{ffserver} but can be to @command{ffmpeg}.
1187 @item -sdp_file @var{file} (@emph{global})
1188 Print sdp information to @var{file}.
1189 This allows dumping sdp information when at least one output isn't an
1192 @item -discard (@emph{input})
1193 Allows discarding specific streams or frames of streams at the demuxer.
1194 Not all demuxers support this.
1201 Default, which discards no frames.
1204 Discard all non-reference frames.
1207 Discard all bidirectional frames.
1210 Discard all frames excepts keyframes.
1218 As a special exception, you can use a bitmap subtitle stream as input: it
1219 will be converted into a video with the same size as the largest video in
1220 the file, or 720x576 if no video is present. Note that this is an
1221 experimental and temporary solution. It will be removed once libavfilter has
1222 proper support for subtitles.
1224 For example, to hardcode subtitles on top of a DVB-T recording stored in
1225 MPEG-TS format, delaying the subtitles by 1 second:
1227 ffmpeg -i input.ts -filter_complex \
1228 '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
1229 -sn -map '#0x2dc' output.mkv
1231 (0x2d0, 0x2dc and 0x2ef are the MPEG-TS PIDs of respectively the video,
1232 audio and subtitles streams; 0:0, 0:3 and 0:7 would have worked too)
1234 @section Preset files
1235 A preset file contains a sequence of @var{option}=@var{value} pairs,
1236 one for each line, specifying a sequence of options which would be
1237 awkward to specify on the command line. Lines starting with the hash
1238 ('#') character are ignored and are used to provide comments. Check
1239 the @file{presets} directory in the FFmpeg source tree for examples.
1241 There are two types of preset files: ffpreset and avpreset files.
1243 @subsection ffpreset files
1244 ffpreset files are specified with the @code{vpre}, @code{apre},
1245 @code{spre}, and @code{fpre} options. The @code{fpre} option takes the
1246 filename of the preset instead of a preset name as input and can be
1247 used for any kind of codec. For the @code{vpre}, @code{apre}, and
1248 @code{spre} options, the options specified in a preset file are
1249 applied to the currently selected codec of the same type as the preset
1252 The argument passed to the @code{vpre}, @code{apre}, and @code{spre}
1253 preset options identifies the preset file to use according to the
1256 First ffmpeg searches for a file named @var{arg}.ffpreset in the
1257 directories @file{$FFMPEG_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
1258 the datadir defined at configuration time (usually @file{PREFIX/share/ffmpeg})
1259 or in a @file{ffpresets} folder along the executable on win32,
1260 in that order. For example, if the argument is @code{libvpx-1080p}, it will
1261 search for the file @file{libvpx-1080p.ffpreset}.
1263 If no such file is found, then ffmpeg will search for a file named
1264 @var{codec_name}-@var{arg}.ffpreset in the above-mentioned
1265 directories, where @var{codec_name} is the name of the codec to which
1266 the preset file options will be applied. For example, if you select
1267 the video codec with @code{-vcodec libvpx} and use @code{-vpre 1080p},
1268 then it will search for the file @file{libvpx-1080p.ffpreset}.
1270 @subsection avpreset files
1271 avpreset files are specified with the @code{pre} option. They work similar to
1272 ffpreset files, but they only allow encoder- specific options. Therefore, an
1273 @var{option}=@var{value} pair specifying an encoder cannot be used.
1275 When the @code{pre} option is specified, ffmpeg will look for files with the
1276 suffix .avpreset in the directories @file{$AVCONV_DATADIR} (if set), and
1277 @file{$HOME/.avconv}, and in the datadir defined at configuration time (usually
1278 @file{PREFIX/share/ffmpeg}), in that order.
1280 First ffmpeg searches for a file named @var{codec_name}-@var{arg}.avpreset in
1281 the above-mentioned directories, where @var{codec_name} is the name of the codec
1282 to which the preset file options will be applied. For example, if you select the
1283 video codec with @code{-vcodec libvpx} and use @code{-pre 1080p}, then it will
1284 search for the file @file{libvpx-1080p.avpreset}.
1286 If no such file is found, then ffmpeg will search for a file named
1287 @var{arg}.avpreset in the same directories.
1296 For streaming at very low bitrates, use a low frame rate
1297 and a small GOP size. This is especially true for RealVideo where
1298 the Linux player does not seem to be very fast, so it can miss
1299 frames. An example is:
1302 ffmpeg -g 3 -r 3 -t 10 -b:v 50k -s qcif -f rv10 /tmp/b.rm
1306 The parameter 'q' which is displayed while encoding is the current
1307 quantizer. The value 1 indicates that a very good quality could
1308 be achieved. The value 31 indicates the worst quality. If q=31 appears
1309 too often, it means that the encoder cannot compress enough to meet
1310 your bitrate. You must either increase the bitrate, decrease the
1311 frame rate or decrease the frame size.
1314 If your computer is not fast enough, you can speed up the
1315 compression at the expense of the compression ratio. You can use
1316 '-me zero' to speed up motion estimation, and '-g 0' to disable
1317 motion estimation completely (you have only I-frames, which means it
1318 is about as good as JPEG compression).
1321 To have very low audio bitrates, reduce the sampling frequency
1322 (down to 22050 Hz for MPEG audio, 22050 or 11025 for AC-3).
1325 To have a constant quality (but a variable bitrate), use the option
1326 '-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst
1333 @c man begin EXAMPLES
1335 @section Video and Audio grabbing
1337 If you specify the input format and device then ffmpeg can grab video
1341 ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
1344 Or with an ALSA audio source (mono input, card id 1) instead of OSS:
1346 ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg
1349 Note that you must activate the right video source and channel before
1350 launching ffmpeg with any TV viewer such as
1351 @uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also
1352 have to set the audio recording levels correctly with a
1355 @section X11 grabbing
1357 Grab the X11 display with ffmpeg via
1360 ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0 /tmp/out.mpg
1363 0.0 is display.screen number of your X11 server, same as
1364 the DISPLAY environment variable.
1367 ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0+10,20 /tmp/out.mpg
1370 0.0 is display.screen number of your X11 server, same as the DISPLAY environment
1371 variable. 10 is the x-offset and 20 the y-offset for the grabbing.
1373 @section Video and Audio file format conversion
1375 Any supported file format and protocol can serve as input to ffmpeg:
1380 You can use YUV files as input:
1383 ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
1386 It will use the files:
1388 /tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
1389 /tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
1392 The Y files use twice the resolution of the U and V files. They are
1393 raw files, without header. They can be generated by all decent video
1394 decoders. You must specify the size of the image with the @option{-s} option
1395 if ffmpeg cannot guess it.
1398 You can input from a raw YUV420P file:
1401 ffmpeg -i /tmp/test.yuv /tmp/out.avi
1404 test.yuv is a file containing raw YUV planar data. Each frame is composed
1405 of the Y plane followed by the U and V planes at half vertical and
1406 horizontal resolution.
1409 You can output to a raw YUV420P file:
1412 ffmpeg -i mydivx.avi hugefile.yuv
1416 You can set several input files and output files:
1419 ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
1422 Converts the audio file a.wav and the raw YUV video file a.yuv
1426 You can also do audio and video conversions at the same time:
1429 ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
1432 Converts a.wav to MPEG audio at 22050 Hz sample rate.
1435 You can encode to several formats at the same time and define a
1436 mapping from input stream to output streams:
1439 ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2
1442 Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
1443 file:index' specifies which input stream is used for each output
1444 stream, in the order of the definition of output streams.
1447 You can transcode decrypted VOBs:
1450 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
1453 This is a typical DVD ripping example; the input is a VOB file, the
1454 output an AVI file with MPEG-4 video and MP3 audio. Note that in this
1455 command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
1456 GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
1457 input video. Furthermore, the audio stream is MP3-encoded so you need
1458 to enable LAME support by passing @code{--enable-libmp3lame} to configure.
1459 The mapping is particularly useful for DVD transcoding
1460 to get the desired audio language.
1462 NOTE: To see the supported input formats, use @code{ffmpeg -formats}.
1465 You can extract images from a video, or create a video from many images:
1467 For extracting images from a video:
1469 ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
1472 This will extract one video frame per second from the video and will
1473 output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg},
1474 etc. Images will be rescaled to fit the new WxH values.
1476 If you want to extract just a limited number of frames, you can use the
1477 above command in combination with the -vframes or -t option, or in
1478 combination with -ss to start extracting from a certain point in time.
1480 For creating a video from many images:
1482 ffmpeg -f image2 -framerate 12 -i foo-%03d.jpeg -s WxH foo.avi
1485 The syntax @code{foo-%03d.jpeg} specifies to use a decimal number
1486 composed of three digits padded with zeroes to express the sequence
1487 number. It is the same syntax supported by the C printf function, but
1488 only formats accepting a normal integer are suitable.
1490 When importing an image sequence, -i also supports expanding
1491 shell-like wildcard patterns (globbing) internally, by selecting the
1492 image2-specific @code{-pattern_type glob} option.
1494 For example, for creating a video from filenames matching the glob pattern
1497 ffmpeg -f image2 -pattern_type glob -framerate 12 -i 'foo-*.jpeg' -s WxH foo.avi
1501 You can put many streams of the same type in the output:
1504 ffmpeg -i test1.avi -i test2.avi -map 1:1 -map 1:0 -map 0:1 -map 0:0 -c copy -y test12.nut
1507 The resulting output file @file{test12.nut} will contain the first four streams
1508 from the input files in reverse order.
1511 To force CBR video output:
1513 ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
1517 The four options lmin, lmax, mblmin and mblmax use 'lambda' units,
1518 but you may use the QP2LAMBDA constant to easily convert from 'q' units:
1520 ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
1526 @include config.texi
1528 @ifset config-avutil
1531 @ifset config-avcodec
1532 @include codecs.texi
1533 @include bitstream_filters.texi
1535 @ifset config-avformat
1536 @include formats.texi
1537 @include protocols.texi
1539 @ifset config-avdevice
1540 @include devices.texi
1542 @ifset config-swresample
1543 @include resampler.texi
1545 @ifset config-swscale
1546 @include scaler.texi
1548 @ifset config-avfilter
1549 @include filters.texi
1557 @url{ffmpeg.html,ffmpeg}
1559 @ifset config-not-all
1560 @url{ffmpeg-all.html,ffmpeg-all},
1562 @url{ffplay.html,ffplay}, @url{ffprobe.html,ffprobe}, @url{ffserver.html,ffserver},
1563 @url{ffmpeg-utils.html,ffmpeg-utils},
1564 @url{ffmpeg-scaler.html,ffmpeg-scaler},
1565 @url{ffmpeg-resampler.html,ffmpeg-resampler},
1566 @url{ffmpeg-codecs.html,ffmpeg-codecs},
1567 @url{ffmpeg-bitstream-filters.html,ffmpeg-bitstream-filters},
1568 @url{ffmpeg-formats.html,ffmpeg-formats},
1569 @url{ffmpeg-devices.html,ffmpeg-devices},
1570 @url{ffmpeg-protocols.html,ffmpeg-protocols},
1571 @url{ffmpeg-filters.html,ffmpeg-filters}
1578 @ifset config-not-all
1581 ffplay(1), ffprobe(1), ffserver(1),
1582 ffmpeg-utils(1), ffmpeg-scaler(1), ffmpeg-resampler(1),
1583 ffmpeg-codecs(1), ffmpeg-bitstream-filters(1), ffmpeg-formats(1),
1584 ffmpeg-devices(1), ffmpeg-protocols(1), ffmpeg-filters(1)
1587 @include authors.texi
1592 @settitle ffmpeg video converter