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 -stream_loop @var{number} (@emph{input})
257 Set number of times input stream shall be looped. Loop 0 means no loop,
258 loop -1 means infinite loop.
260 @item -c[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
261 @itemx -codec[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
262 Select an encoder (when used before an output file) or a decoder (when used
263 before an input file) for one or more streams. @var{codec} is the name of a
264 decoder/encoder or a special value @code{copy} (output only) to indicate that
265 the stream is not to be re-encoded.
269 ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT
271 encodes all video streams with libx264 and copies all audio streams.
273 For each stream, the last matching @code{c} option is applied, so
275 ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT
277 will copy all the streams except the second video, which will be encoded with
278 libx264, and the 138th audio, which will be encoded with libvorbis.
280 @item -t @var{duration} (@emph{input/output})
281 When used as an input option (before @code{-i}), limit the @var{duration} of
282 data read from the input file.
284 When used as an output option (before an output filename), stop writing the
285 output after its duration reaches @var{duration}.
287 @var{duration} must be a time duration specification,
288 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
290 -to and -t are mutually exclusive and -t has priority.
292 @item -to @var{position} (@emph{output})
293 Stop writing the output at @var{position}.
294 @var{position} must be a time duration specification,
295 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
297 -to and -t are mutually exclusive and -t has priority.
299 @item -fs @var{limit_size} (@emph{output})
300 Set the file size limit, expressed in bytes.
302 @item -ss @var{position} (@emph{input/output})
303 When used as an input option (before @code{-i}), seeks in this input file to
304 @var{position}. Note that in most formats it is not possible to seek exactly,
305 so @command{ffmpeg} will seek to the closest seek point before @var{position}.
306 When transcoding and @option{-accurate_seek} is enabled (the default), this
307 extra segment between the seek point and @var{position} will be decoded and
308 discarded. When doing stream copy or when @option{-noaccurate_seek} is used, it
311 When used as an output option (before an output filename), decodes but discards
312 input until the timestamps reach @var{position}.
314 @var{position} must be a time duration specification,
315 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
317 @item -sseof @var{position} (@emph{input/output})
319 Like the @code{-ss} option but relative to the "end of file". That is negative
320 values are earlier in the file, 0 is at EOF.
322 @item -itsoffset @var{offset} (@emph{input})
323 Set the input time offset.
325 @var{offset} must be a time duration specification,
326 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
328 The offset is added to the timestamps of the input files. Specifying
329 a positive offset means that the corresponding streams are delayed by
330 the time duration specified in @var{offset}.
332 @item -timestamp @var{date} (@emph{output})
333 Set the recording timestamp in the container.
335 @var{date} must be a date specification,
336 see @ref{date syntax,,the Date section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
338 @item -metadata[:metadata_specifier] @var{key}=@var{value} (@emph{output,per-metadata})
339 Set a metadata key/value pair.
341 An optional @var{metadata_specifier} may be given to set metadata
342 on streams or chapters. See @code{-map_metadata} documentation for
345 This option overrides metadata set with @code{-map_metadata}. It is
346 also possible to delete metadata by using an empty value.
348 For example, for setting the title in the output file:
350 ffmpeg -i in.avi -metadata title="my title" out.flv
353 To set the language of the first audio stream:
355 ffmpeg -i INPUT -metadata:s:a:0 language=eng OUTPUT
358 @item -program [title=@var{title}:][program_num=@var{program_num}:]st=@var{stream}[:st=@var{stream}...] (@emph{output})
360 Creates a program with the specified @var{title}, @var{program_num} and adds the specified
361 @var{stream}(s) to it.
363 @item -target @var{type} (@emph{output})
364 Specify target file type (@code{vcd}, @code{svcd}, @code{dvd}, @code{dv},
365 @code{dv50}). @var{type} may be prefixed with @code{pal-}, @code{ntsc-} or
366 @code{film-} to use the corresponding standard. All the format options
367 (bitrate, codecs, buffer sizes) are then set automatically. You can just type:
370 ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
373 Nevertheless you can specify additional options as long as you know
374 they do not conflict with the standard, as in:
377 ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
380 @item -dframes @var{number} (@emph{output})
381 Set the number of data frames to output. This is an alias for @code{-frames:d}.
383 @item -frames[:@var{stream_specifier}] @var{framecount} (@emph{output,per-stream})
384 Stop writing to the stream after @var{framecount} frames.
386 @item -q[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
387 @itemx -qscale[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
388 Use fixed quality scale (VBR). The meaning of @var{q}/@var{qscale} is
390 If @var{qscale} is used without a @var{stream_specifier} then it applies only
391 to the video stream, this is to maintain compatibility with previous behavior
392 and as specifying the same codec specific value to 2 different codecs that is
393 audio and video generally is not what is intended when no stream_specifier is
396 @anchor{filter_option}
397 @item -filter[:@var{stream_specifier}] @var{filtergraph} (@emph{output,per-stream})
398 Create the filtergraph specified by @var{filtergraph} and use it to
401 @var{filtergraph} is a description of the filtergraph to apply to
402 the stream, and must have a single input and a single output of the
403 same type of the stream. In the filtergraph, the input is associated
404 to the label @code{in}, and the output to the label @code{out}. See
405 the ffmpeg-filters manual for more information about the filtergraph
408 See the @ref{filter_complex_option,,-filter_complex option} if you
409 want to create filtergraphs with multiple inputs and/or outputs.
411 @item -filter_script[:@var{stream_specifier}] @var{filename} (@emph{output,per-stream})
412 This option is similar to @option{-filter}, the only difference is that its
413 argument is the name of the file from which a filtergraph description is to be
416 @item -pre[:@var{stream_specifier}] @var{preset_name} (@emph{output,per-stream})
417 Specify the preset for matching stream(s).
419 @item -stats (@emph{global})
420 Print encoding progress/statistics. It is on by default, to explicitly
421 disable it you need to specify @code{-nostats}.
423 @item -progress @var{url} (@emph{global})
424 Send program-friendly progress information to @var{url}.
426 Progress information is written approximately every second and at the end of
427 the encoding process. It is made of "@var{key}=@var{value}" lines. @var{key}
428 consists of only alphanumeric characters. The last key of a sequence of
429 progress information is always "progress".
432 Enable interaction on standard input. On by default unless standard input is
433 used as an input. To explicitly disable interaction you need to specify
436 Disabling interaction on standard input is useful, for example, if
437 ffmpeg is in the background process group. Roughly the same result can
438 be achieved with @code{ffmpeg ... < /dev/null} but it requires a
441 @item -debug_ts (@emph{global})
442 Print timestamp information. It is off by default. This option is
443 mostly useful for testing and debugging purposes, and the output
444 format may change from one version to another, so it should not be
445 employed by portable scripts.
447 See also the option @code{-fdebug ts}.
449 @item -attach @var{filename} (@emph{output})
450 Add an attachment to the output file. This is supported by a few formats
451 like Matroska for e.g. fonts used in rendering subtitles. Attachments
452 are implemented as a specific type of stream, so this option will add
453 a new stream to the file. It is then possible to use per-stream options
454 on this stream in the usual way. Attachment streams created with this
455 option will be created after all the other streams (i.e. those created
456 with @code{-map} or automatic mappings).
458 Note that for Matroska you also have to set the mimetype metadata tag:
460 ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv
462 (assuming that the attachment stream will be third in the output file).
464 @item -dump_attachment[:@var{stream_specifier}] @var{filename} (@emph{input,per-stream})
465 Extract the matching attachment stream into a file named @var{filename}. If
466 @var{filename} is empty, then the value of the @code{filename} metadata tag
469 E.g. to extract the first attachment to a file named 'out.ttf':
471 ffmpeg -dump_attachment:t:0 out.ttf -i INPUT
473 To extract all attachments to files determined by the @code{filename} tag:
475 ffmpeg -dump_attachment:t "" -i INPUT
478 Technical note -- attachments are implemented as codec extradata, so this
479 option can actually be used to extract extradata from any stream, not just
483 Disable automatically rotating video based on file metadata.
487 @section Video Options
490 @item -vframes @var{number} (@emph{output})
491 Set the number of video frames to output. This is an alias for @code{-frames:v}.
492 @item -r[:@var{stream_specifier}] @var{fps} (@emph{input/output,per-stream})
493 Set frame rate (Hz value, fraction or abbreviation).
495 As an input option, ignore any timestamps stored in the file and instead
496 generate timestamps assuming constant frame rate @var{fps}.
497 This is not the same as the @option{-framerate} option used for some input formats
498 like image2 or v4l2 (it used to be the same in older versions of FFmpeg).
499 If in doubt use @option{-framerate} instead of the input option @option{-r}.
501 As an output option, duplicate or drop input frames to achieve constant output
502 frame rate @var{fps}.
504 @item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream})
507 As an input option, this is a shortcut for the @option{video_size} private
508 option, recognized by some demuxers for which the frame size is either not
509 stored in the file or is configurable -- e.g. raw video or video grabbers.
511 As an output option, this inserts the @code{scale} video filter to the
512 @emph{end} of the corresponding filtergraph. Please use the @code{scale} filter
513 directly to insert it at the beginning or some other place.
515 The format is @samp{wxh} (default - same as source).
517 @item -aspect[:@var{stream_specifier}] @var{aspect} (@emph{output,per-stream})
518 Set the video display aspect ratio specified by @var{aspect}.
520 @var{aspect} can be a floating point number string, or a string of the
521 form @var{num}:@var{den}, where @var{num} and @var{den} are the
522 numerator and denominator of the aspect ratio. For example "4:3",
523 "16:9", "1.3333", and "1.7777" are valid argument values.
525 If used together with @option{-vcodec copy}, it will affect the aspect ratio
526 stored at container level, but not the aspect ratio stored in encoded
527 frames, if it exists.
529 @item -vn (@emph{output})
530 Disable video recording.
532 @item -vcodec @var{codec} (@emph{output})
533 Set the video codec. This is an alias for @code{-codec:v}.
535 @item -pass[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
536 Select the pass number (1 or 2). It is used to do two-pass
537 video encoding. The statistics of the video are recorded in the first
538 pass into a log file (see also the option -passlogfile),
539 and in the second pass that log file is used to generate the video
540 at the exact requested bitrate.
541 On pass 1, you may just deactivate audio and set output to null,
542 examples for Windows and Unix:
544 ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
545 ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null
548 @item -passlogfile[:@var{stream_specifier}] @var{prefix} (@emph{output,per-stream})
549 Set two-pass log file name prefix to @var{prefix}, the default file name
550 prefix is ``ffmpeg2pass''. The complete file name will be
551 @file{PREFIX-N.log}, where N is a number specific to the output
554 @item -vf @var{filtergraph} (@emph{output})
555 Create the filtergraph specified by @var{filtergraph} and use it to
558 This is an alias for @code{-filter:v}, see the @ref{filter_option,,-filter option}.
561 @section Advanced Video options
564 @item -pix_fmt[:@var{stream_specifier}] @var{format} (@emph{input/output,per-stream})
565 Set pixel format. Use @code{-pix_fmts} to show all the supported
567 If the selected pixel format can not be selected, ffmpeg will print a
568 warning and select the best pixel format supported by the encoder.
569 If @var{pix_fmt} is prefixed by a @code{+}, ffmpeg will exit with an error
570 if the requested pixel format can not be selected, and automatic conversions
571 inside filtergraphs are disabled.
572 If @var{pix_fmt} is a single @code{+}, ffmpeg selects the same pixel format
573 as the input (or graph output) and automatic conversions are disabled.
575 @item -sws_flags @var{flags} (@emph{input/output})
580 @item -rc_override[:@var{stream_specifier}] @var{override} (@emph{output,per-stream})
581 Rate control override for specific intervals, formatted as "int,int,int"
582 list separated with slashes. Two first values are the beginning and
583 end frame numbers, last one is quantizer to use if positive, or quality
587 Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
588 Use this option if your input file is interlaced and you want
589 to keep the interlaced format for minimum losses.
590 The alternative is to deinterlace the input stream with
591 @option{-deinterlace}, but deinterlacing introduces losses.
593 Calculate PSNR of compressed frames.
595 Dump video coding statistics to @file{vstats_HHMMSS.log}.
596 @item -vstats_file @var{file}
597 Dump video coding statistics to @var{file}.
598 @item -top[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
599 top=1/bottom=0/auto=-1 field first
600 @item -dc @var{precision}
602 @item -vtag @var{fourcc/tag} (@emph{output})
603 Force video tag/fourcc. This is an alias for @code{-tag:v}.
604 @item -qphist (@emph{global})
606 @item -vbsf @var{bitstream_filter}
609 @item -force_key_frames[:@var{stream_specifier}] @var{time}[,@var{time}...] (@emph{output,per-stream})
610 @item -force_key_frames[:@var{stream_specifier}] expr:@var{expr} (@emph{output,per-stream})
611 Force key frames at the specified timestamps, more precisely at the first
612 frames after each specified time.
614 If the argument is prefixed with @code{expr:}, the string @var{expr}
615 is interpreted like an expression and is evaluated for each frame. A
616 key frame is forced in case the evaluation is non-zero.
618 If one of the times is "@code{chapters}[@var{delta}]", it is expanded into
619 the time of the beginning of all chapters in the file, shifted by
620 @var{delta}, expressed as a time in seconds.
621 This option can be useful to ensure that a seek point is present at a
622 chapter mark or any other designated place in the output file.
624 For example, to insert a key frame at 5 minutes, plus key frames 0.1 second
625 before the beginning of every chapter:
627 -force_key_frames 0:05:00,chapters-0.1
630 The expression in @var{expr} can contain the following constants:
633 the number of current processed frame, starting from 0
635 the number of forced frames
637 the number of the previous forced frame, it is @code{NAN} when no
638 keyframe was forced yet
640 the time of the previous forced frame, it is @code{NAN} when no
641 keyframe was forced yet
643 the time of the current processed frame
646 For example to force a key frame every 5 seconds, you can specify:
648 -force_key_frames expr:gte(t,n_forced*5)
651 To force a key frame 5 seconds after the time of the last forced one,
652 starting from second 13:
654 -force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5))
657 Note that forcing too many keyframes is very harmful for the lookahead
658 algorithms of certain encoders: using fixed-GOP options or similar
659 would be more efficient.
661 @item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream})
662 When doing stream copy, copy also non-key frames found at the
665 @item -hwaccel[:@var{stream_specifier}] @var{hwaccel} (@emph{input,per-stream})
666 Use hardware acceleration to decode the matching stream(s). The allowed values
667 of @var{hwaccel} are:
670 Do not use any hardware acceleration (the default).
673 Automatically select the hardware acceleration method.
676 Use Apple VDA hardware acceleration.
679 Use VDPAU (Video Decode and Presentation API for Unix) hardware acceleration.
682 Use DXVA2 (DirectX Video Acceleration) hardware acceleration.
685 Use the Intel QuickSync Video acceleration for video transcoding.
687 Unlike most other values, this option does not enable accelerated decoding (that
688 is used automatically whenever a qsv decoder is selected), but accelerated
689 transcoding, without copying the frames into the system memory.
691 For it to work, both the decoder and the encoder must support QSV acceleration
692 and no filters must be used.
695 This option has no effect if the selected hwaccel is not available or not
696 supported by the chosen decoder.
698 Note that most acceleration methods are intended for playback and will not be
699 faster than software decoding on modern CPUs. Additionally, @command{ffmpeg}
700 will usually need to copy the decoded frames from the GPU memory into the system
701 memory, resulting in further performance loss. This option is thus mainly
704 @item -hwaccel_device[:@var{stream_specifier}] @var{hwaccel_device} (@emph{input,per-stream})
705 Select a device to use for hardware acceleration.
707 This option only makes sense when the @option{-hwaccel} option is also
708 specified. Its exact meaning depends on the specific hardware acceleration
713 For VDPAU, this option specifies the X11 display/screen to use. If this option
714 is not specified, the value of the @var{DISPLAY} environment variable is used
717 For DXVA2, this option should contain the number of the display adapter to use.
718 If this option is not specified, the default adapter is used.
721 For QSV, this option corresponds to the valus of MFX_IMPL_* . Allowed values
736 List all hardware acceleration methods supported in this build of ffmpeg.
740 @section Audio Options
743 @item -aframes @var{number} (@emph{output})
744 Set the number of audio frames to output. This is an alias for @code{-frames:a}.
745 @item -ar[:@var{stream_specifier}] @var{freq} (@emph{input/output,per-stream})
746 Set the audio sampling frequency. For output streams it is set by
747 default to the frequency of the corresponding input stream. For input
748 streams this option only makes sense for audio grabbing devices and raw
749 demuxers and is mapped to the corresponding demuxer options.
750 @item -aq @var{q} (@emph{output})
751 Set the audio quality (codec-specific, VBR). This is an alias for -q:a.
752 @item -ac[:@var{stream_specifier}] @var{channels} (@emph{input/output,per-stream})
753 Set the number of audio channels. For output streams it is set by
754 default to the number of input audio channels. For input streams
755 this option only makes sense for audio grabbing devices and raw demuxers
756 and is mapped to the corresponding demuxer options.
757 @item -an (@emph{output})
758 Disable audio recording.
759 @item -acodec @var{codec} (@emph{input/output})
760 Set the audio codec. This is an alias for @code{-codec:a}.
761 @item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream})
762 Set the audio sample format. Use @code{-sample_fmts} to get a list
763 of supported sample formats.
765 @item -af @var{filtergraph} (@emph{output})
766 Create the filtergraph specified by @var{filtergraph} and use it to
769 This is an alias for @code{-filter:a}, see the @ref{filter_option,,-filter option}.
772 @section Advanced Audio options
775 @item -atag @var{fourcc/tag} (@emph{output})
776 Force audio tag/fourcc. This is an alias for @code{-tag:a}.
777 @item -absf @var{bitstream_filter}
779 @item -guess_layout_max @var{channels} (@emph{input,per-stream})
780 If some input channel layout is not known, try to guess only if it
781 corresponds to at most the specified number of channels. For example, 2
782 tells to @command{ffmpeg} to recognize 1 channel as mono and 2 channels as
783 stereo but not 6 channels as 5.1. The default is to always try to guess. Use
784 0 to disable all guessing.
787 @section Subtitle options
790 @item -scodec @var{codec} (@emph{input/output})
791 Set the subtitle codec. This is an alias for @code{-codec:s}.
792 @item -sn (@emph{output})
793 Disable subtitle recording.
794 @item -sbsf @var{bitstream_filter}
798 @section Advanced Subtitle options
802 @item -fix_sub_duration
803 Fix subtitles durations. For each subtitle, wait for the next packet in the
804 same stream and adjust the duration of the first to avoid overlap. This is
805 necessary with some subtitles codecs, especially DVB subtitles, because the
806 duration in the original packet is only a rough estimate and the end is
807 actually marked by an empty subtitle frame. Failing to use this option when
808 necessary can result in exaggerated durations or muxing failures due to
809 non-monotonic timestamps.
811 Note that this option will delay the output of all data until the next
812 subtitle packet is decoded: it may increase memory consumption and latency a
815 @item -canvas_size @var{size}
816 Set the size of the canvas used to render subtitles.
820 @section Advanced options
823 @item -map [-]@var{input_file_id}[:@var{stream_specifier}][,@var{sync_file_id}[:@var{stream_specifier}]] | @var{[linklabel]} (@emph{output})
825 Designate one or more input streams as a source for the output file. Each input
826 stream is identified by the input file index @var{input_file_id} and
827 the input stream index @var{input_stream_id} within the input
828 file. Both indices start at 0. If specified,
829 @var{sync_file_id}:@var{stream_specifier} sets which input stream
830 is used as a presentation sync reference.
832 The first @code{-map} option on the command line specifies the
833 source for output stream 0, the second @code{-map} option specifies
834 the source for output stream 1, etc.
836 A @code{-} character before the stream identifier creates a "negative" mapping.
837 It disables matching streams from already created mappings.
839 An alternative @var{[linklabel]} form will map outputs from complex filter
840 graphs (see the @option{-filter_complex} option) to the output file.
841 @var{linklabel} must correspond to a defined output link label in the graph.
843 For example, to map ALL streams from the first input file to output
845 ffmpeg -i INPUT -map 0 output
848 For example, if you have two audio streams in the first input file,
849 these streams are identified by "0:0" and "0:1". You can use
850 @code{-map} to select which streams to place in an output file. For
853 ffmpeg -i INPUT -map 0:1 out.wav
855 will map the input stream in @file{INPUT} identified by "0:1" to
856 the (single) output stream in @file{out.wav}.
858 For example, to select the stream with index 2 from input file
859 @file{a.mov} (specified by the identifier "0:2"), and stream with
860 index 6 from input @file{b.mov} (specified by the identifier "1:6"),
861 and copy them to the output file @file{out.mov}:
863 ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
866 To select all video and the third audio stream from an input file:
868 ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT
871 To map all the streams except the second audio, use negative mappings
873 ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT
876 To pick the English audio stream:
878 ffmpeg -i INPUT -map 0:m:language:eng OUTPUT
881 Note that using this option disables the default mappings for this output file.
883 @item -ignore_unknown
884 Ignore input streams with unknown type instead of failing if copying
885 such streams is attempted.
888 Allow input streams with unknown type to be copied instead of failing if copying
889 such streams is attempted.
891 @item -map_channel [@var{input_file_id}.@var{stream_specifier}.@var{channel_id}|-1][:@var{output_file_id}.@var{stream_specifier}]
892 Map an audio channel from a given input to an output. If
893 @var{output_file_id}.@var{stream_specifier} is not set, the audio channel will
894 be mapped on all the audio streams.
896 Using "-1" instead of
897 @var{input_file_id}.@var{stream_specifier}.@var{channel_id} will map a muted
900 For example, assuming @var{INPUT} is a stereo audio file, you can switch the
901 two audio channels with the following command:
903 ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT
906 If you want to mute the first channel and keep the second:
908 ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT
911 The order of the "-map_channel" option specifies the order of the channels in
912 the output stream. The output channel layout is guessed from the number of
913 channels mapped (mono if one "-map_channel", stereo if two, etc.). Using "-ac"
914 in combination of "-map_channel" makes the channel gain levels to be updated if
915 input and output channel layouts don't match (for instance two "-map_channel"
916 options and "-ac 6").
918 You can also extract each channel of an input to specific outputs; the following
919 command extracts two channels of the @var{INPUT} audio stream (file 0, stream 0)
920 to the respective @var{OUTPUT_CH0} and @var{OUTPUT_CH1} outputs:
922 ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1
925 The following example splits the channels of a stereo input into two separate
926 streams, which are put into the same output file:
928 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
931 Note that currently each output stream can only contain channels from a single
932 input stream; you can't for example use "-map_channel" to pick multiple input
933 audio channels contained in different streams (from the same or different files)
934 and merge them into a single output stream. It is therefore not currently
935 possible, for example, to turn two separate mono streams into a single stereo
936 stream. However splitting a stereo stream into two single channel mono streams
939 If you need this feature, a possible workaround is to use the @emph{amerge}
940 filter. For example, if you need to merge a media (here @file{input.mkv}) with 2
941 mono audio streams into one single stereo channel audio stream (and keep the
942 video stream), you can use the following command:
944 ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv
947 @item -map_metadata[:@var{metadata_spec_out}] @var{infile}[:@var{metadata_spec_in}] (@emph{output,per-metadata})
948 Set metadata information of the next output file from @var{infile}. Note that
949 those are file indices (zero-based), not filenames.
950 Optional @var{metadata_spec_in/out} parameters specify, which metadata to copy.
951 A metadata specifier can have the following forms:
954 global metadata, i.e. metadata that applies to the whole file
956 @item @var{s}[:@var{stream_spec}]
957 per-stream metadata. @var{stream_spec} is a stream specifier as described
958 in the @ref{Stream specifiers} chapter. In an input metadata specifier, the first
959 matching stream is copied from. In an output metadata specifier, all matching
960 streams are copied to.
962 @item @var{c}:@var{chapter_index}
963 per-chapter metadata. @var{chapter_index} is the zero-based chapter index.
965 @item @var{p}:@var{program_index}
966 per-program metadata. @var{program_index} is the zero-based program index.
968 If metadata specifier is omitted, it defaults to global.
970 By default, global metadata is copied from the first input file,
971 per-stream and per-chapter metadata is copied along with streams/chapters. These
972 default mappings are disabled by creating any mapping of the relevant type. A negative
973 file index can be used to create a dummy mapping that just disables automatic copying.
975 For example to copy metadata from the first stream of the input file to global metadata
978 ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3
981 To do the reverse, i.e. copy global metadata to all audio streams:
983 ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv
985 Note that simple @code{0} would work as well in this example, since global
986 metadata is assumed by default.
988 @item -map_chapters @var{input_file_index} (@emph{output})
989 Copy chapters from input file with index @var{input_file_index} to the next
990 output file. If no chapter mapping is specified, then chapters are copied from
991 the first input file with at least one chapter. Use a negative file index to
992 disable any chapter copying.
994 @item -benchmark (@emph{global})
995 Show benchmarking information at the end of an encode.
996 Shows CPU time used and maximum memory consumption.
997 Maximum memory consumption is not supported on all systems,
998 it will usually display as 0 if not supported.
999 @item -benchmark_all (@emph{global})
1000 Show benchmarking information during the encode.
1001 Shows CPU time used in various steps (audio/video encode/decode).
1002 @item -timelimit @var{duration} (@emph{global})
1003 Exit after ffmpeg has been running for @var{duration} seconds.
1004 @item -dump (@emph{global})
1005 Dump each input packet to stderr.
1006 @item -hex (@emph{global})
1007 When dumping packets, also dump the payload.
1008 @item -re (@emph{input})
1009 Read input at native frame rate. Mainly used to simulate a grab device.
1010 or live input stream (e.g. when reading from a file). Should not be used
1011 with actual grab devices or live input streams (where it can cause packet
1013 By default @command{ffmpeg} attempts to read the input(s) as fast as possible.
1014 This option will slow down the reading of the input(s) to the native frame rate
1015 of the input(s). It is useful for real-time output (e.g. live streaming).
1017 Loop over the input stream. Currently it works only for image
1018 streams. This option is used for automatic FFserver testing.
1019 This option is deprecated, use -loop 1.
1020 @item -loop_output @var{number_of_times}
1021 Repeatedly loop output for formats that support looping such as animated GIF
1022 (0 will loop the output infinitely).
1023 This option is deprecated, use -loop.
1024 @item -vsync @var{parameter}
1026 For compatibility reasons old values can be specified as numbers.
1027 Newly added values will have to be specified as strings always.
1030 @item 0, passthrough
1031 Each frame is passed with its timestamp from the demuxer to the muxer.
1033 Frames will be duplicated and dropped to achieve exactly the requested
1034 constant frame rate.
1036 Frames are passed through with their timestamp or dropped so as to
1037 prevent 2 frames from having the same timestamp.
1039 As passthrough but destroys all timestamps, making the muxer generate
1040 fresh timestamps based on frame-rate.
1042 Chooses between 1 and 2 depending on muxer capabilities. This is the
1046 Note that the timestamps may be further modified by the muxer, after this.
1047 For example, in the case that the format option @option{avoid_negative_ts}
1050 With -map you can select from which stream the timestamps should be
1051 taken. You can leave either video or audio unchanged and sync the
1052 remaining stream(s) to the unchanged one.
1054 @item -frame_drop_threshold @var{parameter}
1055 Frame drop threshold, which specifies how much behind video frames can
1056 be before they are dropped. In frame rate units, so 1.0 is one frame.
1057 The default is -1.1. One possible usecase is to avoid framedrops in case
1058 of noisy timestamps or to increase frame drop precision in case of exact
1061 @item -async @var{samples_per_second}
1062 Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
1063 the parameter is the maximum samples per second by which the audio is changed.
1064 -async 1 is a special case where only the start of the audio stream is corrected
1065 without any later correction.
1067 Note that the timestamps may be further modified by the muxer, after this.
1068 For example, in the case that the format option @option{avoid_negative_ts}
1071 This option has been deprecated. Use the @code{aresample} audio filter instead.
1074 Do not process input timestamps, but keep their values without trying
1075 to sanitize them. In particular, do not remove the initial start time
1078 Note that, depending on the @option{vsync} option or on specific muxer
1079 processing (e.g. in case the format option @option{avoid_negative_ts}
1080 is enabled) the output timestamps may mismatch with the input
1081 timestamps even when this option is selected.
1083 @item -start_at_zero
1084 When used with @option{copyts}, shift input timestamps so they start at zero.
1086 This means that using e.g. @code{-ss 50} will make output timestamps start at
1087 50 seconds, regardless of what timestamp the input file started at.
1089 @item -copytb @var{mode}
1090 Specify how to set the encoder timebase when stream copying. @var{mode} is an
1091 integer numeric value, and can assume one of the following values:
1095 Use the demuxer timebase.
1097 The time base is copied to the output encoder from the corresponding input
1098 demuxer. This is sometimes required to avoid non monotonically increasing
1099 timestamps when copying video streams with variable frame rate.
1102 Use the decoder timebase.
1104 The time base is copied to the output encoder from the corresponding input
1108 Try to make the choice automatically, in order to generate a sane output.
1111 Default value is -1.
1113 @item -shortest (@emph{output})
1114 Finish encoding when the shortest input stream ends.
1115 @item -dts_delta_threshold
1116 Timestamp discontinuity delta threshold.
1117 @item -muxdelay @var{seconds} (@emph{input})
1118 Set the maximum demux-decode delay.
1119 @item -muxpreload @var{seconds} (@emph{input})
1120 Set the initial demux-decode delay.
1121 @item -streamid @var{output-stream-index}:@var{new-value} (@emph{output})
1122 Assign a new stream-id value to an output stream. This option should be
1123 specified prior to the output filename to which it applies.
1124 For the situation where multiple output files exist, a streamid
1125 may be reassigned to a different value.
1127 For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for
1128 an output mpegts file:
1130 ffmpeg -i infile -streamid 0:33 -streamid 1:36 out.ts
1133 @item -bsf[:@var{stream_specifier}] @var{bitstream_filters} (@emph{output,per-stream})
1134 Set bitstream filters for matching streams. @var{bitstream_filters} is
1135 a comma-separated list of bitstream filters. Use the @code{-bsfs} option
1136 to get the list of bitstream filters.
1138 ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264
1141 ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt
1144 @item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{input/output,per-stream})
1145 Force a tag/fourcc for matching streams.
1147 @item -timecode @var{hh}:@var{mm}:@var{ss}SEP@var{ff}
1148 Specify Timecode for writing. @var{SEP} is ':' for non drop timecode and ';'
1151 ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg
1154 @anchor{filter_complex_option}
1155 @item -filter_complex @var{filtergraph} (@emph{global})
1156 Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
1157 outputs. For simple graphs -- those with one input and one output of the same
1158 type -- see the @option{-filter} options. @var{filtergraph} is a description of
1159 the filtergraph, as described in the ``Filtergraph syntax'' section of the
1160 ffmpeg-filters manual.
1162 Input link labels must refer to input streams using the
1163 @code{[file_index:stream_specifier]} syntax (i.e. the same as @option{-map}
1164 uses). If @var{stream_specifier} matches multiple streams, the first one will be
1165 used. An unlabeled input will be connected to the first unused input stream of
1168 Output link labels are referred to with @option{-map}. Unlabeled outputs are
1169 added to the first output file.
1171 Note that with this option it is possible to use only lavfi sources without
1174 For example, to overlay an image over video
1176 ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
1179 Here @code{[0:v]} refers to the first video stream in the first input file,
1180 which is linked to the first (main) input of the overlay filter. Similarly the
1181 first video stream in the second input is linked to the second (overlay) input
1184 Assuming there is only one video stream in each input file, we can omit input
1185 labels, so the above is equivalent to
1187 ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map
1191 Furthermore we can omit the output label and the single output from the filter
1192 graph will be added to the output file automatically, so we can simply write
1194 ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv
1197 To generate 5 seconds of pure red video using lavfi @code{color} source:
1199 ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv
1202 @item -lavfi @var{filtergraph} (@emph{global})
1203 Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
1204 outputs. Equivalent to @option{-filter_complex}.
1206 @item -filter_complex_script @var{filename} (@emph{global})
1207 This option is similar to @option{-filter_complex}, the only difference is that
1208 its argument is the name of the file from which a complex filtergraph
1209 description is to be read.
1211 @item -accurate_seek (@emph{input})
1212 This option enables or disables accurate seeking in input files with the
1213 @option{-ss} option. It is enabled by default, so seeking is accurate when
1214 transcoding. Use @option{-noaccurate_seek} to disable it, which may be useful
1215 e.g. when copying some streams and transcoding the others.
1217 @item -seek_timestamp (@emph{input})
1218 This option enables or disables seeking by timestamp in input files with the
1219 @option{-ss} option. It is disabled by default. If enabled, the argument
1220 to the @option{-ss} option is considered an actual timestamp, and is not
1221 offset by the start time of the file. This matters only for files which do
1222 not start from timestamp 0, such as transport streams.
1224 @item -thread_queue_size @var{size} (@emph{input})
1225 This option sets the maximum number of queued packets when reading from the
1226 file or device. With low latency / high rate live streams, packets may be
1227 discarded if they are not read in a timely manner; raising this value can
1230 @item -override_ffserver (@emph{global})
1231 Overrides the input specifications from @command{ffserver}. Using this
1232 option you can map any input stream to @command{ffserver} and control
1233 many aspects of the encoding from @command{ffmpeg}. Without this
1234 option @command{ffmpeg} will transmit to @command{ffserver} what is
1235 requested by @command{ffserver}.
1237 The option is intended for cases where features are needed that cannot be
1238 specified to @command{ffserver} but can be to @command{ffmpeg}.
1240 @item -sdp_file @var{file} (@emph{global})
1241 Print sdp information for an output stream to @var{file}.
1242 This allows dumping sdp information when at least one output isn't an
1243 rtp stream. (Requires at least one of the output formats to be rtp).
1245 @item -discard (@emph{input})
1246 Allows discarding specific streams or frames of streams at the demuxer.
1247 Not all demuxers support this.
1254 Default, which discards no frames.
1257 Discard all non-reference frames.
1260 Discard all bidirectional frames.
1263 Discard all frames excepts keyframes.
1269 @item -abort_on @var{flags} (@emph{global})
1270 Stop and abort on various conditions. The following flags are available:
1274 No packets were passed to the muxer, the output is empty.
1277 @item -xerror (@emph{global})
1278 Stop and exit on error
1282 As a special exception, you can use a bitmap subtitle stream as input: it
1283 will be converted into a video with the same size as the largest video in
1284 the file, or 720x576 if no video is present. Note that this is an
1285 experimental and temporary solution. It will be removed once libavfilter has
1286 proper support for subtitles.
1288 For example, to hardcode subtitles on top of a DVB-T recording stored in
1289 MPEG-TS format, delaying the subtitles by 1 second:
1291 ffmpeg -i input.ts -filter_complex \
1292 '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
1293 -sn -map '#0x2dc' output.mkv
1295 (0x2d0, 0x2dc and 0x2ef are the MPEG-TS PIDs of respectively the video,
1296 audio and subtitles streams; 0:0, 0:3 and 0:7 would have worked too)
1298 @section Preset files
1299 A preset file contains a sequence of @var{option}=@var{value} pairs,
1300 one for each line, specifying a sequence of options which would be
1301 awkward to specify on the command line. Lines starting with the hash
1302 ('#') character are ignored and are used to provide comments. Check
1303 the @file{presets} directory in the FFmpeg source tree for examples.
1305 There are two types of preset files: ffpreset and avpreset files.
1307 @subsection ffpreset files
1308 ffpreset files are specified with the @code{vpre}, @code{apre},
1309 @code{spre}, and @code{fpre} options. The @code{fpre} option takes the
1310 filename of the preset instead of a preset name as input and can be
1311 used for any kind of codec. For the @code{vpre}, @code{apre}, and
1312 @code{spre} options, the options specified in a preset file are
1313 applied to the currently selected codec of the same type as the preset
1316 The argument passed to the @code{vpre}, @code{apre}, and @code{spre}
1317 preset options identifies the preset file to use according to the
1320 First ffmpeg searches for a file named @var{arg}.ffpreset in the
1321 directories @file{$FFMPEG_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
1322 the datadir defined at configuration time (usually @file{PREFIX/share/ffmpeg})
1323 or in a @file{ffpresets} folder along the executable on win32,
1324 in that order. For example, if the argument is @code{libvpx-1080p}, it will
1325 search for the file @file{libvpx-1080p.ffpreset}.
1327 If no such file is found, then ffmpeg will search for a file named
1328 @var{codec_name}-@var{arg}.ffpreset in the above-mentioned
1329 directories, where @var{codec_name} is the name of the codec to which
1330 the preset file options will be applied. For example, if you select
1331 the video codec with @code{-vcodec libvpx} and use @code{-vpre 1080p},
1332 then it will search for the file @file{libvpx-1080p.ffpreset}.
1334 @subsection avpreset files
1335 avpreset files are specified with the @code{pre} option. They work similar to
1336 ffpreset files, but they only allow encoder- specific options. Therefore, an
1337 @var{option}=@var{value} pair specifying an encoder cannot be used.
1339 When the @code{pre} option is specified, ffmpeg will look for files with the
1340 suffix .avpreset in the directories @file{$AVCONV_DATADIR} (if set), and
1341 @file{$HOME/.avconv}, and in the datadir defined at configuration time (usually
1342 @file{PREFIX/share/ffmpeg}), in that order.
1344 First ffmpeg searches for a file named @var{codec_name}-@var{arg}.avpreset in
1345 the above-mentioned directories, where @var{codec_name} is the name of the codec
1346 to which the preset file options will be applied. For example, if you select the
1347 video codec with @code{-vcodec libvpx} and use @code{-pre 1080p}, then it will
1348 search for the file @file{libvpx-1080p.avpreset}.
1350 If no such file is found, then ffmpeg will search for a file named
1351 @var{arg}.avpreset in the same directories.
1356 @c man begin EXAMPLES
1358 @section Video and Audio grabbing
1360 If you specify the input format and device then ffmpeg can grab video
1364 ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
1367 Or with an ALSA audio source (mono input, card id 1) instead of OSS:
1369 ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg
1372 Note that you must activate the right video source and channel before
1373 launching ffmpeg with any TV viewer such as
1374 @uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also
1375 have to set the audio recording levels correctly with a
1378 @section X11 grabbing
1380 Grab the X11 display with ffmpeg via
1383 ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0 /tmp/out.mpg
1386 0.0 is display.screen number of your X11 server, same as
1387 the DISPLAY environment variable.
1390 ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0+10,20 /tmp/out.mpg
1393 0.0 is display.screen number of your X11 server, same as the DISPLAY environment
1394 variable. 10 is the x-offset and 20 the y-offset for the grabbing.
1396 @section Video and Audio file format conversion
1398 Any supported file format and protocol can serve as input to ffmpeg:
1403 You can use YUV files as input:
1406 ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
1409 It will use the files:
1411 /tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
1412 /tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
1415 The Y files use twice the resolution of the U and V files. They are
1416 raw files, without header. They can be generated by all decent video
1417 decoders. You must specify the size of the image with the @option{-s} option
1418 if ffmpeg cannot guess it.
1421 You can input from a raw YUV420P file:
1424 ffmpeg -i /tmp/test.yuv /tmp/out.avi
1427 test.yuv is a file containing raw YUV planar data. Each frame is composed
1428 of the Y plane followed by the U and V planes at half vertical and
1429 horizontal resolution.
1432 You can output to a raw YUV420P file:
1435 ffmpeg -i mydivx.avi hugefile.yuv
1439 You can set several input files and output files:
1442 ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
1445 Converts the audio file a.wav and the raw YUV video file a.yuv
1449 You can also do audio and video conversions at the same time:
1452 ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
1455 Converts a.wav to MPEG audio at 22050 Hz sample rate.
1458 You can encode to several formats at the same time and define a
1459 mapping from input stream to output streams:
1462 ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2
1465 Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
1466 file:index' specifies which input stream is used for each output
1467 stream, in the order of the definition of output streams.
1470 You can transcode decrypted VOBs:
1473 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
1476 This is a typical DVD ripping example; the input is a VOB file, the
1477 output an AVI file with MPEG-4 video and MP3 audio. Note that in this
1478 command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
1479 GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
1480 input video. Furthermore, the audio stream is MP3-encoded so you need
1481 to enable LAME support by passing @code{--enable-libmp3lame} to configure.
1482 The mapping is particularly useful for DVD transcoding
1483 to get the desired audio language.
1485 NOTE: To see the supported input formats, use @code{ffmpeg -formats}.
1488 You can extract images from a video, or create a video from many images:
1490 For extracting images from a video:
1492 ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
1495 This will extract one video frame per second from the video and will
1496 output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg},
1497 etc. Images will be rescaled to fit the new WxH values.
1499 If you want to extract just a limited number of frames, you can use the
1500 above command in combination with the -vframes or -t option, or in
1501 combination with -ss to start extracting from a certain point in time.
1503 For creating a video from many images:
1505 ffmpeg -f image2 -framerate 12 -i foo-%03d.jpeg -s WxH foo.avi
1508 The syntax @code{foo-%03d.jpeg} specifies to use a decimal number
1509 composed of three digits padded with zeroes to express the sequence
1510 number. It is the same syntax supported by the C printf function, but
1511 only formats accepting a normal integer are suitable.
1513 When importing an image sequence, -i also supports expanding
1514 shell-like wildcard patterns (globbing) internally, by selecting the
1515 image2-specific @code{-pattern_type glob} option.
1517 For example, for creating a video from filenames matching the glob pattern
1520 ffmpeg -f image2 -pattern_type glob -framerate 12 -i 'foo-*.jpeg' -s WxH foo.avi
1524 You can put many streams of the same type in the output:
1527 ffmpeg -i test1.avi -i test2.avi -map 1:1 -map 1:0 -map 0:1 -map 0:0 -c copy -y test12.nut
1530 The resulting output file @file{test12.nut} will contain the first four streams
1531 from the input files in reverse order.
1534 To force CBR video output:
1536 ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
1540 The four options lmin, lmax, mblmin and mblmax use 'lambda' units,
1541 but you may use the QP2LAMBDA constant to easily convert from 'q' units:
1543 ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
1549 @include config.texi
1551 @ifset config-avutil
1554 @ifset config-avcodec
1555 @include codecs.texi
1556 @include bitstream_filters.texi
1558 @ifset config-avformat
1559 @include formats.texi
1560 @include protocols.texi
1562 @ifset config-avdevice
1563 @include devices.texi
1565 @ifset config-swresample
1566 @include resampler.texi
1568 @ifset config-swscale
1569 @include scaler.texi
1571 @ifset config-avfilter
1572 @include filters.texi
1580 @url{ffmpeg.html,ffmpeg}
1582 @ifset config-not-all
1583 @url{ffmpeg-all.html,ffmpeg-all},
1585 @url{ffplay.html,ffplay}, @url{ffprobe.html,ffprobe}, @url{ffserver.html,ffserver},
1586 @url{ffmpeg-utils.html,ffmpeg-utils},
1587 @url{ffmpeg-scaler.html,ffmpeg-scaler},
1588 @url{ffmpeg-resampler.html,ffmpeg-resampler},
1589 @url{ffmpeg-codecs.html,ffmpeg-codecs},
1590 @url{ffmpeg-bitstream-filters.html,ffmpeg-bitstream-filters},
1591 @url{ffmpeg-formats.html,ffmpeg-formats},
1592 @url{ffmpeg-devices.html,ffmpeg-devices},
1593 @url{ffmpeg-protocols.html,ffmpeg-protocols},
1594 @url{ffmpeg-filters.html,ffmpeg-filters}
1601 @ifset config-not-all
1604 ffplay(1), ffprobe(1), ffserver(1),
1605 ffmpeg-utils(1), ffmpeg-scaler(1), ffmpeg-resampler(1),
1606 ffmpeg-codecs(1), ffmpeg-bitstream-filters(1), ffmpeg-formats(1),
1607 ffmpeg-devices(1), ffmpeg-protocols(1), ffmpeg-filters(1)
1610 @include authors.texi
1615 @settitle ffmpeg video converter