1 \input texinfo @c -*- texinfo -*-
2 @documentencoding UTF-8
4 @settitle ffmpeg Documentation
6 @center @titlefont{ffmpeg Documentation}
15 ffmpeg [@var{global_options}] @{[@var{input_file_options}] -i @file{input_url}@} ... @{[@var{output_file_options}] @file{output_url}@} ...
18 @c man begin DESCRIPTION
20 @command{ffmpeg} is a very fast video and audio converter that can also grab from
21 a live audio/video source. It can also convert between arbitrary sample
22 rates and resize video on the fly with a high quality polyphase filter.
24 @command{ffmpeg} reads from an arbitrary number of input "files" (which can be regular
25 files, pipes, network streams, grabbing devices, etc.), specified by the
26 @code{-i} option, and writes to an arbitrary number of output "files", which are
27 specified by a plain output url. Anything found on the command line which
28 cannot be interpreted as an option is considered to be an output url.
30 Each input or output url can, in principle, contain any number of streams of
31 different types (video/audio/subtitle/attachment/data). The allowed number and/or
32 types of streams may be limited by the container format. Selecting which
33 streams from which inputs will go into which output is either done automatically
34 or with the @code{-map} option (see the Stream selection chapter).
36 To refer to input files in options, you must use their indices (0-based). E.g.
37 the first input file is @code{0}, the second is @code{1}, etc. Similarly, streams
38 within a file are referred to by their indices. E.g. @code{2:3} refers to the
39 fourth stream in the third input file. Also see the Stream specifiers chapter.
41 As a general rule, options are applied to the next specified
42 file. Therefore, order is important, and you can have the same
43 option on the command line multiple times. Each occurrence is
44 then applied to the next input or output file.
45 Exceptions from this rule are the global options (e.g. verbosity level),
46 which should be specified first.
48 Do not mix input and output files -- first specify all input files, then all
49 output files. Also do not mix options which belong to different files. All
50 options apply ONLY to the next input or output file and are reset between files.
54 To set the video bitrate of the output file to 64 kbit/s:
56 ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi
60 To force the frame rate of the output file to 24 fps:
62 ffmpeg -i input.avi -r 24 output.avi
66 To force the frame rate of the input file (valid for raw formats only)
67 to 1 fps and the frame rate of the output file to 24 fps:
69 ffmpeg -r 1 -i input.m2v -r 24 output.avi
73 The format option may be needed for raw input files.
75 @c man end DESCRIPTION
77 @chapter Detailed description
78 @c man begin DETAILED DESCRIPTION
80 The transcoding process in @command{ffmpeg} for each output can be described by
81 the following diagram:
84 _______ ______________
86 | input | demuxer | encoded data | decoder
87 | file | ---------> | packets | -----+
88 |_______| |______________| |
95 ________ ______________ |
97 | output | <-------- | encoded data | <----+
98 | file | muxer | packets | encoder
99 |________| |______________|
104 @command{ffmpeg} calls the libavformat library (containing demuxers) to read
105 input files and get packets containing encoded data from them. When there are
106 multiple input files, @command{ffmpeg} tries to keep them synchronized by
107 tracking lowest timestamp on any active input stream.
109 Encoded packets are then passed to the decoder (unless streamcopy is selected
110 for the stream, see further for a description). The decoder produces
111 uncompressed frames (raw video/PCM audio/...) which can be processed further by
112 filtering (see next section). After filtering, the frames are passed to the
113 encoder, which encodes them and outputs encoded packets. Finally those are
114 passed to the muxer, which writes the encoded packets to the output file.
117 Before encoding, @command{ffmpeg} can process raw audio and video frames using
118 filters from the libavfilter library. Several chained filters form a filter
119 graph. @command{ffmpeg} distinguishes between two types of filtergraphs:
122 @subsection Simple filtergraphs
123 Simple filtergraphs are those that have exactly one input and output, both of
124 the same type. In the above diagram they can be represented by simply inserting
125 an additional step between decoding and encoding:
128 _________ ______________
130 | decoded | | encoded data |
131 | frames |\ _ | packets |
132 |_________| \ /||______________|
134 simple _\|| | / encoder
135 filtergraph | filtered |/
141 Simple filtergraphs are configured with the per-stream @option{-filter} option
142 (with @option{-vf} and @option{-af} aliases for video and audio respectively).
143 A simple filtergraph for video can look for example like this:
146 _______ _____________ _______ ________
148 | input | ---> | deinterlace | ---> | scale | ---> | output |
149 |_______| |_____________| |_______| |________|
153 Note that some filters change frame properties but not frame contents. E.g. the
154 @code{fps} filter in the example above changes number of frames, but does not
155 touch the frame contents. Another example is the @code{setpts} filter, which
156 only sets timestamps and otherwise passes the frames unchanged.
158 @subsection Complex filtergraphs
159 Complex filtergraphs are those which cannot be described as simply a linear
160 processing chain applied to one stream. This is the case, for example, when the graph has
161 more than one input and/or output, or when output stream type is different from
162 input. They can be represented with the following diagram:
167 | input 0 |\ __________
169 \ _________ /| output 0 |
171 _________ \| complex | /
173 | input 1 |---->| filter |\
174 |_________| | | \ __________
177 _________ / |_________| |__________|
184 Complex filtergraphs are configured with the @option{-filter_complex} option.
185 Note that this option is global, since a complex filtergraph, by its nature,
186 cannot be unambiguously associated with a single stream or file.
188 The @option{-lavfi} option is equivalent to @option{-filter_complex}.
190 A trivial example of a complex filtergraph is the @code{overlay} filter, which
191 has two video inputs and one video output, containing one video overlaid on top
192 of the other. Its audio counterpart is the @code{amix} filter.
195 Stream copy is a mode selected by supplying the @code{copy} parameter to the
196 @option{-codec} option. It makes @command{ffmpeg} omit the decoding and encoding
197 step for the specified stream, so it does only demuxing and muxing. It is useful
198 for changing the container format or modifying container-level metadata. The
199 diagram above will, in this case, simplify to this:
202 _______ ______________ ________
204 | input | demuxer | encoded data | muxer | output |
205 | file | ---------> | packets | -------> | file |
206 |_______| |______________| |________|
210 Since there is no decoding or encoding, it is very fast and there is no quality
211 loss. However, it might not work in some cases because of many factors. Applying
212 filters is obviously also impossible, since filters work on uncompressed data.
214 @c man end DETAILED DESCRIPTION
216 @chapter Stream selection
217 @c man begin STREAM SELECTION
219 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/-dn} 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{url} (@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 url), 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{input/output})
293 Stop writing the output or reading the input 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. No further chunk of bytes is written
301 after the limit is exceeded. The size of the output file is slightly more than the
304 @item -ss @var{position} (@emph{input/output})
305 When used as an input option (before @code{-i}), seeks in this input file to
306 @var{position}. Note that in most formats it is not possible to seek exactly,
307 so @command{ffmpeg} will seek to the closest seek point before @var{position}.
308 When transcoding and @option{-accurate_seek} is enabled (the default), this
309 extra segment between the seek point and @var{position} will be decoded and
310 discarded. When doing stream copy or when @option{-noaccurate_seek} is used, it
313 When used as an output option (before an output url), decodes but discards
314 input until the timestamps reach @var{position}.
316 @var{position} must be a time duration specification,
317 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
319 @item -sseof @var{position} (@emph{input/output})
321 Like the @code{-ss} option but relative to the "end of file". That is negative
322 values are earlier in the file, 0 is at EOF.
324 @item -itsoffset @var{offset} (@emph{input})
325 Set the input time offset.
327 @var{offset} must be a time duration specification,
328 see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
330 The offset is added to the timestamps of the input files. Specifying
331 a positive offset means that the corresponding streams are delayed by
332 the time duration specified in @var{offset}.
334 @item -timestamp @var{date} (@emph{output})
335 Set the recording timestamp in the container.
337 @var{date} must be a date specification,
338 see @ref{date syntax,,the Date section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
340 @item -metadata[:metadata_specifier] @var{key}=@var{value} (@emph{output,per-metadata})
341 Set a metadata key/value pair.
343 An optional @var{metadata_specifier} may be given to set metadata
344 on streams, chapters or programs. See @code{-map_metadata}
345 documentation for details.
347 This option overrides metadata set with @code{-map_metadata}. It is
348 also possible to delete metadata by using an empty value.
350 For example, for setting the title in the output file:
352 ffmpeg -i in.avi -metadata title="my title" out.flv
355 To set the language of the first audio stream:
357 ffmpeg -i INPUT -metadata:s:a:0 language=eng OUTPUT
360 @item -disposition[:stream_specifier] @var{value} (@emph{output,per-stream})
361 Sets the disposition for a stream.
363 This option overrides the disposition copied from the input stream. It is also
364 possible to delete the disposition by setting it to 0.
366 The following dispositions are recognized:
375 @item hearing_impaired
376 @item visual_impaired
383 For example, to make the second audio stream the default stream:
385 ffmpeg -i in.mkv -disposition:a:1 default out.mkv
388 To make the second subtitle stream the default stream and remove the default
389 disposition from the first subtitle stream:
391 ffmpeg -i INPUT -disposition:s:0 0 -disposition:s:1 default OUTPUT
394 @item -program [title=@var{title}:][program_num=@var{program_num}:]st=@var{stream}[:st=@var{stream}...] (@emph{output})
396 Creates a program with the specified @var{title}, @var{program_num} and adds the specified
397 @var{stream}(s) to it.
399 @item -target @var{type} (@emph{output})
400 Specify target file type (@code{vcd}, @code{svcd}, @code{dvd}, @code{dv},
401 @code{dv50}). @var{type} may be prefixed with @code{pal-}, @code{ntsc-} or
402 @code{film-} to use the corresponding standard. All the format options
403 (bitrate, codecs, buffer sizes) are then set automatically. You can just type:
406 ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
409 Nevertheless you can specify additional options as long as you know
410 they do not conflict with the standard, as in:
413 ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
416 @item -dframes @var{number} (@emph{output})
417 Set the number of data frames to output. This is an obsolete alias for
418 @code{-frames:d}, which you should use instead.
420 @item -frames[:@var{stream_specifier}] @var{framecount} (@emph{output,per-stream})
421 Stop writing to the stream after @var{framecount} frames.
423 @item -q[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
424 @itemx -qscale[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
425 Use fixed quality scale (VBR). The meaning of @var{q}/@var{qscale} is
427 If @var{qscale} is used without a @var{stream_specifier} then it applies only
428 to the video stream, this is to maintain compatibility with previous behavior
429 and as specifying the same codec specific value to 2 different codecs that is
430 audio and video generally is not what is intended when no stream_specifier is
433 @anchor{filter_option}
434 @item -filter[:@var{stream_specifier}] @var{filtergraph} (@emph{output,per-stream})
435 Create the filtergraph specified by @var{filtergraph} and use it to
438 @var{filtergraph} is a description of the filtergraph to apply to
439 the stream, and must have a single input and a single output of the
440 same type of the stream. In the filtergraph, the input is associated
441 to the label @code{in}, and the output to the label @code{out}. See
442 the ffmpeg-filters manual for more information about the filtergraph
445 See the @ref{filter_complex_option,,-filter_complex option} if you
446 want to create filtergraphs with multiple inputs and/or outputs.
448 @item -filter_script[:@var{stream_specifier}] @var{filename} (@emph{output,per-stream})
449 This option is similar to @option{-filter}, the only difference is that its
450 argument is the name of the file from which a filtergraph description is to be
453 @item -filter_threads @var{nb_threads} (@emph{global})
454 Defines how many threads are used to process a filter pipeline. Each pipeline
455 will produce a thread pool with this many threads available for parallel processing.
456 The default is the number of available CPUs.
458 @item -pre[:@var{stream_specifier}] @var{preset_name} (@emph{output,per-stream})
459 Specify the preset for matching stream(s).
461 @item -stats (@emph{global})
462 Print encoding progress/statistics. It is on by default, to explicitly
463 disable it you need to specify @code{-nostats}.
465 @item -progress @var{url} (@emph{global})
466 Send program-friendly progress information to @var{url}.
468 Progress information is written approximately every second and at the end of
469 the encoding process. It is made of "@var{key}=@var{value}" lines. @var{key}
470 consists of only alphanumeric characters. The last key of a sequence of
471 progress information is always "progress".
474 Enable interaction on standard input. On by default unless standard input is
475 used as an input. To explicitly disable interaction you need to specify
478 Disabling interaction on standard input is useful, for example, if
479 ffmpeg is in the background process group. Roughly the same result can
480 be achieved with @code{ffmpeg ... < /dev/null} but it requires a
483 @item -debug_ts (@emph{global})
484 Print timestamp information. It is off by default. This option is
485 mostly useful for testing and debugging purposes, and the output
486 format may change from one version to another, so it should not be
487 employed by portable scripts.
489 See also the option @code{-fdebug ts}.
491 @item -attach @var{filename} (@emph{output})
492 Add an attachment to the output file. This is supported by a few formats
493 like Matroska for e.g. fonts used in rendering subtitles. Attachments
494 are implemented as a specific type of stream, so this option will add
495 a new stream to the file. It is then possible to use per-stream options
496 on this stream in the usual way. Attachment streams created with this
497 option will be created after all the other streams (i.e. those created
498 with @code{-map} or automatic mappings).
500 Note that for Matroska you also have to set the mimetype metadata tag:
502 ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv
504 (assuming that the attachment stream will be third in the output file).
506 @item -dump_attachment[:@var{stream_specifier}] @var{filename} (@emph{input,per-stream})
507 Extract the matching attachment stream into a file named @var{filename}. If
508 @var{filename} is empty, then the value of the @code{filename} metadata tag
511 E.g. to extract the first attachment to a file named 'out.ttf':
513 ffmpeg -dump_attachment:t:0 out.ttf -i INPUT
515 To extract all attachments to files determined by the @code{filename} tag:
517 ffmpeg -dump_attachment:t "" -i INPUT
520 Technical note -- attachments are implemented as codec extradata, so this
521 option can actually be used to extract extradata from any stream, not just
525 Disable automatically rotating video based on file metadata.
529 @section Video Options
532 @item -vframes @var{number} (@emph{output})
533 Set the number of video frames to output. This is an obsolete alias for
534 @code{-frames:v}, which you should use instead.
535 @item -r[:@var{stream_specifier}] @var{fps} (@emph{input/output,per-stream})
536 Set frame rate (Hz value, fraction or abbreviation).
538 As an input option, ignore any timestamps stored in the file and instead
539 generate timestamps assuming constant frame rate @var{fps}.
540 This is not the same as the @option{-framerate} option used for some input formats
541 like image2 or v4l2 (it used to be the same in older versions of FFmpeg).
542 If in doubt use @option{-framerate} instead of the input option @option{-r}.
544 As an output option, duplicate or drop input frames to achieve constant output
545 frame rate @var{fps}.
547 @item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream})
550 As an input option, this is a shortcut for the @option{video_size} private
551 option, recognized by some demuxers for which the frame size is either not
552 stored in the file or is configurable -- e.g. raw video or video grabbers.
554 As an output option, this inserts the @code{scale} video filter to the
555 @emph{end} of the corresponding filtergraph. Please use the @code{scale} filter
556 directly to insert it at the beginning or some other place.
558 The format is @samp{wxh} (default - same as source).
560 @item -aspect[:@var{stream_specifier}] @var{aspect} (@emph{output,per-stream})
561 Set the video display aspect ratio specified by @var{aspect}.
563 @var{aspect} can be a floating point number string, or a string of the
564 form @var{num}:@var{den}, where @var{num} and @var{den} are the
565 numerator and denominator of the aspect ratio. For example "4:3",
566 "16:9", "1.3333", and "1.7777" are valid argument values.
568 If used together with @option{-vcodec copy}, it will affect the aspect ratio
569 stored at container level, but not the aspect ratio stored in encoded
570 frames, if it exists.
572 @item -vn (@emph{output})
573 Disable video recording.
575 @item -vcodec @var{codec} (@emph{output})
576 Set the video codec. This is an alias for @code{-codec:v}.
578 @item -pass[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
579 Select the pass number (1 or 2). It is used to do two-pass
580 video encoding. The statistics of the video are recorded in the first
581 pass into a log file (see also the option -passlogfile),
582 and in the second pass that log file is used to generate the video
583 at the exact requested bitrate.
584 On pass 1, you may just deactivate audio and set output to null,
585 examples for Windows and Unix:
587 ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
588 ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null
591 @item -passlogfile[:@var{stream_specifier}] @var{prefix} (@emph{output,per-stream})
592 Set two-pass log file name prefix to @var{prefix}, the default file name
593 prefix is ``ffmpeg2pass''. The complete file name will be
594 @file{PREFIX-N.log}, where N is a number specific to the output
597 @item -vf @var{filtergraph} (@emph{output})
598 Create the filtergraph specified by @var{filtergraph} and use it to
601 This is an alias for @code{-filter:v}, see the @ref{filter_option,,-filter option}.
604 @section Advanced Video options
607 @item -pix_fmt[:@var{stream_specifier}] @var{format} (@emph{input/output,per-stream})
608 Set pixel format. Use @code{-pix_fmts} to show all the supported
610 If the selected pixel format can not be selected, ffmpeg will print a
611 warning and select the best pixel format supported by the encoder.
612 If @var{pix_fmt} is prefixed by a @code{+}, ffmpeg will exit with an error
613 if the requested pixel format can not be selected, and automatic conversions
614 inside filtergraphs are disabled.
615 If @var{pix_fmt} is a single @code{+}, ffmpeg selects the same pixel format
616 as the input (or graph output) and automatic conversions are disabled.
618 @item -sws_flags @var{flags} (@emph{input/output})
623 @item -rc_override[:@var{stream_specifier}] @var{override} (@emph{output,per-stream})
624 Rate control override for specific intervals, formatted as "int,int,int"
625 list separated with slashes. Two first values are the beginning and
626 end frame numbers, last one is quantizer to use if positive, or quality
630 Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
631 Use this option if your input file is interlaced and you want
632 to keep the interlaced format for minimum losses.
633 The alternative is to deinterlace the input stream with
634 @option{-deinterlace}, but deinterlacing introduces losses.
636 Calculate PSNR of compressed frames.
638 Dump video coding statistics to @file{vstats_HHMMSS.log}.
639 @item -vstats_file @var{file}
640 Dump video coding statistics to @var{file}.
641 @item -vstats_version @var{file}
642 Specifies which version of the vstats format to use. Default is 2.
646 @code{frame= %5d q= %2.1f PSNR= %6.2f f_size= %6d s_size= %8.0fkB time= %0.3f br= %7.1fkbits/s avg_br= %7.1fkbits/s}
650 @code{out= %2d st= %2d frame= %5d q= %2.1f PSNR= %6.2f f_size= %6d s_size= %8.0fkB time= %0.3f br= %7.1fkbits/s avg_br= %7.1fkbits/s}
651 @item -top[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
652 top=1/bottom=0/auto=-1 field first
653 @item -dc @var{precision}
655 @item -vtag @var{fourcc/tag} (@emph{output})
656 Force video tag/fourcc. This is an alias for @code{-tag:v}.
657 @item -qphist (@emph{global})
659 @item -vbsf @var{bitstream_filter}
662 @item -force_key_frames[:@var{stream_specifier}] @var{time}[,@var{time}...] (@emph{output,per-stream})
663 @item -force_key_frames[:@var{stream_specifier}] expr:@var{expr} (@emph{output,per-stream})
664 Force key frames at the specified timestamps, more precisely at the first
665 frames after each specified time.
667 If the argument is prefixed with @code{expr:}, the string @var{expr}
668 is interpreted like an expression and is evaluated for each frame. A
669 key frame is forced in case the evaluation is non-zero.
671 If one of the times is "@code{chapters}[@var{delta}]", it is expanded into
672 the time of the beginning of all chapters in the file, shifted by
673 @var{delta}, expressed as a time in seconds.
674 This option can be useful to ensure that a seek point is present at a
675 chapter mark or any other designated place in the output file.
677 For example, to insert a key frame at 5 minutes, plus key frames 0.1 second
678 before the beginning of every chapter:
680 -force_key_frames 0:05:00,chapters-0.1
683 The expression in @var{expr} can contain the following constants:
686 the number of current processed frame, starting from 0
688 the number of forced frames
690 the number of the previous forced frame, it is @code{NAN} when no
691 keyframe was forced yet
693 the time of the previous forced frame, it is @code{NAN} when no
694 keyframe was forced yet
696 the time of the current processed frame
699 For example to force a key frame every 5 seconds, you can specify:
701 -force_key_frames expr:gte(t,n_forced*5)
704 To force a key frame 5 seconds after the time of the last forced one,
705 starting from second 13:
707 -force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5))
710 Note that forcing too many keyframes is very harmful for the lookahead
711 algorithms of certain encoders: using fixed-GOP options or similar
712 would be more efficient.
714 @item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream})
715 When doing stream copy, copy also non-key frames found at the
718 @item -init_hw_device @var{type}[=@var{name}][:@var{device}[,@var{key=value}...]]
719 Initialise a new hardware device of type @var{type} called @var{name}, using the
720 given device parameters.
721 If no name is specified it will receive a default name of the form "@var{type}%d".
723 The meaning of @var{device} and the following arguments depends on the
728 @var{device} is the number of the CUDA device.
731 @var{device} is the number of the Direct3D 9 display adapter.
734 @var{device} is either an X11 display name or a DRM render node.
735 If not specified, it will attempt to open the default X11 display (@emph{$DISPLAY})
736 and then the first DRM render node (@emph{/dev/dri/renderD128}).
739 @var{device} is an X11 display name.
740 If not specified, it will attempt to open the default X11 display (@emph{$DISPLAY}).
743 @var{device} selects a value in @samp{MFX_IMPL_*}. Allowed values are:
754 If not specified, @samp{auto_any} is used.
755 (Note that it may be easier to achieve the desired result for QSV by creating the
756 platform-appropriate subdevice (@samp{dxva2} or @samp{vaapi}) and then deriving a
757 QSV device from that.)
761 @item -init_hw_device @var{type}[=@var{name}]@@@var{source}
762 Initialise a new hardware device of type @var{type} called @var{name},
763 deriving it from the existing device with the name @var{source}.
765 @item -init_hw_device list
766 List all hardware device types supported in this build of ffmpeg.
768 @item -filter_hw_device @var{name}
769 Pass the hardware device called @var{name} to all filters in any filter graph.
770 This can be used to set the device to upload to with the @code{hwupload} filter,
771 or the device to map to with the @code{hwmap} filter. Other filters may also
772 make use of this parameter when they require a hardware device. Note that this
773 is typically only required when the input is not already in hardware frames -
774 when it is, filters will derive the device they require from the context of the
775 frames they receive as input.
777 This is a global setting, so all filters will receive the same device.
779 @item -hwaccel[:@var{stream_specifier}] @var{hwaccel} (@emph{input,per-stream})
780 Use hardware acceleration to decode the matching stream(s). The allowed values
781 of @var{hwaccel} are:
784 Do not use any hardware acceleration (the default).
787 Automatically select the hardware acceleration method.
790 Use VDPAU (Video Decode and Presentation API for Unix) hardware acceleration.
793 Use DXVA2 (DirectX Video Acceleration) hardware acceleration.
796 Use VAAPI (Video Acceleration API) hardware acceleration.
799 Use the Intel QuickSync Video acceleration for video transcoding.
801 Unlike most other values, this option does not enable accelerated decoding (that
802 is used automatically whenever a qsv decoder is selected), but accelerated
803 transcoding, without copying the frames into the system memory.
805 For it to work, both the decoder and the encoder must support QSV acceleration
806 and no filters must be used.
809 This option has no effect if the selected hwaccel is not available or not
810 supported by the chosen decoder.
812 Note that most acceleration methods are intended for playback and will not be
813 faster than software decoding on modern CPUs. Additionally, @command{ffmpeg}
814 will usually need to copy the decoded frames from the GPU memory into the system
815 memory, resulting in further performance loss. This option is thus mainly
818 @item -hwaccel_device[:@var{stream_specifier}] @var{hwaccel_device} (@emph{input,per-stream})
819 Select a device to use for hardware acceleration.
821 This option only makes sense when the @option{-hwaccel} option is also specified.
822 It can either refer to an existing device created with @option{-init_hw_device}
823 by name, or it can create a new device as if
824 @samp{-init_hw_device} @var{type}:@var{hwaccel_device}
825 were called immediately before.
828 List all hardware acceleration methods supported in this build of ffmpeg.
832 @section Audio Options
835 @item -aframes @var{number} (@emph{output})
836 Set the number of audio frames to output. This is an obsolete alias for
837 @code{-frames:a}, which you should use instead.
838 @item -ar[:@var{stream_specifier}] @var{freq} (@emph{input/output,per-stream})
839 Set the audio sampling frequency. For output streams it is set by
840 default to the frequency of the corresponding input stream. For input
841 streams this option only makes sense for audio grabbing devices and raw
842 demuxers and is mapped to the corresponding demuxer options.
843 @item -aq @var{q} (@emph{output})
844 Set the audio quality (codec-specific, VBR). This is an alias for -q:a.
845 @item -ac[:@var{stream_specifier}] @var{channels} (@emph{input/output,per-stream})
846 Set the number of audio channels. For output streams it is set by
847 default to the number of input audio channels. For input streams
848 this option only makes sense for audio grabbing devices and raw demuxers
849 and is mapped to the corresponding demuxer options.
850 @item -an (@emph{output})
851 Disable audio recording.
852 @item -acodec @var{codec} (@emph{input/output})
853 Set the audio codec. This is an alias for @code{-codec:a}.
854 @item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream})
855 Set the audio sample format. Use @code{-sample_fmts} to get a list
856 of supported sample formats.
858 @item -af @var{filtergraph} (@emph{output})
859 Create the filtergraph specified by @var{filtergraph} and use it to
862 This is an alias for @code{-filter:a}, see the @ref{filter_option,,-filter option}.
865 @section Advanced Audio options
868 @item -atag @var{fourcc/tag} (@emph{output})
869 Force audio tag/fourcc. This is an alias for @code{-tag:a}.
870 @item -absf @var{bitstream_filter}
872 @item -guess_layout_max @var{channels} (@emph{input,per-stream})
873 If some input channel layout is not known, try to guess only if it
874 corresponds to at most the specified number of channels. For example, 2
875 tells to @command{ffmpeg} to recognize 1 channel as mono and 2 channels as
876 stereo but not 6 channels as 5.1. The default is to always try to guess. Use
877 0 to disable all guessing.
880 @section Subtitle options
883 @item -scodec @var{codec} (@emph{input/output})
884 Set the subtitle codec. This is an alias for @code{-codec:s}.
885 @item -sn (@emph{output})
886 Disable subtitle recording.
887 @item -sbsf @var{bitstream_filter}
891 @section Advanced Subtitle options
895 @item -fix_sub_duration
896 Fix subtitles durations. For each subtitle, wait for the next packet in the
897 same stream and adjust the duration of the first to avoid overlap. This is
898 necessary with some subtitles codecs, especially DVB subtitles, because the
899 duration in the original packet is only a rough estimate and the end is
900 actually marked by an empty subtitle frame. Failing to use this option when
901 necessary can result in exaggerated durations or muxing failures due to
902 non-monotonic timestamps.
904 Note that this option will delay the output of all data until the next
905 subtitle packet is decoded: it may increase memory consumption and latency a
908 @item -canvas_size @var{size}
909 Set the size of the canvas used to render subtitles.
913 @section Advanced options
916 @item -map [-]@var{input_file_id}[:@var{stream_specifier}][?][,@var{sync_file_id}[:@var{stream_specifier}]] | @var{[linklabel]} (@emph{output})
918 Designate one or more input streams as a source for the output file. Each input
919 stream is identified by the input file index @var{input_file_id} and
920 the input stream index @var{input_stream_id} within the input
921 file. Both indices start at 0. If specified,
922 @var{sync_file_id}:@var{stream_specifier} sets which input stream
923 is used as a presentation sync reference.
925 The first @code{-map} option on the command line specifies the
926 source for output stream 0, the second @code{-map} option specifies
927 the source for output stream 1, etc.
929 A @code{-} character before the stream identifier creates a "negative" mapping.
930 It disables matching streams from already created mappings.
932 A trailing @code{?} after the stream index will allow the map to be
933 optional: if the map matches no streams the map will be ignored instead
934 of failing. Note the map will still fail if an invalid input file index
935 is used; such as if the map refers to a non-existent input.
937 An alternative @var{[linklabel]} form will map outputs from complex filter
938 graphs (see the @option{-filter_complex} option) to the output file.
939 @var{linklabel} must correspond to a defined output link label in the graph.
941 For example, to map ALL streams from the first input file to output
943 ffmpeg -i INPUT -map 0 output
946 For example, if you have two audio streams in the first input file,
947 these streams are identified by "0:0" and "0:1". You can use
948 @code{-map} to select which streams to place in an output file. For
951 ffmpeg -i INPUT -map 0:1 out.wav
953 will map the input stream in @file{INPUT} identified by "0:1" to
954 the (single) output stream in @file{out.wav}.
956 For example, to select the stream with index 2 from input file
957 @file{a.mov} (specified by the identifier "0:2"), and stream with
958 index 6 from input @file{b.mov} (specified by the identifier "1:6"),
959 and copy them to the output file @file{out.mov}:
961 ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
964 To select all video and the third audio stream from an input file:
966 ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT
969 To map all the streams except the second audio, use negative mappings
971 ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT
974 To map the video and audio streams from the first input, and using the
975 trailing @code{?}, ignore the audio mapping if no audio streams exist in
978 ffmpeg -i INPUT -map 0:v -map 0:a? OUTPUT
981 To pick the English audio stream:
983 ffmpeg -i INPUT -map 0:m:language:eng OUTPUT
986 Note that using this option disables the default mappings for this output file.
988 @item -ignore_unknown
989 Ignore input streams with unknown type instead of failing if copying
990 such streams is attempted.
993 Allow input streams with unknown type to be copied instead of failing if copying
994 such streams is attempted.
996 @item -map_channel [@var{input_file_id}.@var{stream_specifier}.@var{channel_id}|-1][?][:@var{output_file_id}.@var{stream_specifier}]
997 Map an audio channel from a given input to an output. If
998 @var{output_file_id}.@var{stream_specifier} is not set, the audio channel will
999 be mapped on all the audio streams.
1001 Using "-1" instead of
1002 @var{input_file_id}.@var{stream_specifier}.@var{channel_id} will map a muted
1005 A trailing @code{?} will allow the map_channel to be
1006 optional: if the map_channel matches no channel the map_channel will be ignored instead
1009 For example, assuming @var{INPUT} is a stereo audio file, you can switch the
1010 two audio channels with the following command:
1012 ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT
1015 If you want to mute the first channel and keep the second:
1017 ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT
1020 The order of the "-map_channel" option specifies the order of the channels in
1021 the output stream. The output channel layout is guessed from the number of
1022 channels mapped (mono if one "-map_channel", stereo if two, etc.). Using "-ac"
1023 in combination of "-map_channel" makes the channel gain levels to be updated if
1024 input and output channel layouts don't match (for instance two "-map_channel"
1025 options and "-ac 6").
1027 You can also extract each channel of an input to specific outputs; the following
1028 command extracts two channels of the @var{INPUT} audio stream (file 0, stream 0)
1029 to the respective @var{OUTPUT_CH0} and @var{OUTPUT_CH1} outputs:
1031 ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1
1034 The following example splits the channels of a stereo input into two separate
1035 streams, which are put into the same output file:
1037 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
1040 Note that currently each output stream can only contain channels from a single
1041 input stream; you can't for example use "-map_channel" to pick multiple input
1042 audio channels contained in different streams (from the same or different files)
1043 and merge them into a single output stream. It is therefore not currently
1044 possible, for example, to turn two separate mono streams into a single stereo
1045 stream. However splitting a stereo stream into two single channel mono streams
1048 If you need this feature, a possible workaround is to use the @emph{amerge}
1049 filter. For example, if you need to merge a media (here @file{input.mkv}) with 2
1050 mono audio streams into one single stereo channel audio stream (and keep the
1051 video stream), you can use the following command:
1053 ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv
1056 To map the first two audio channels from the first input, and using the
1057 trailing @code{?}, ignore the audio channel mapping if the first input is
1058 mono instead of stereo:
1060 ffmpeg -i INPUT -map_channel 0.0.0 -map_channel 0.0.1? OUTPUT
1063 @item -map_metadata[:@var{metadata_spec_out}] @var{infile}[:@var{metadata_spec_in}] (@emph{output,per-metadata})
1064 Set metadata information of the next output file from @var{infile}. Note that
1065 those are file indices (zero-based), not filenames.
1066 Optional @var{metadata_spec_in/out} parameters specify, which metadata to copy.
1067 A metadata specifier can have the following forms:
1070 global metadata, i.e. metadata that applies to the whole file
1072 @item @var{s}[:@var{stream_spec}]
1073 per-stream metadata. @var{stream_spec} is a stream specifier as described
1074 in the @ref{Stream specifiers} chapter. In an input metadata specifier, the first
1075 matching stream is copied from. In an output metadata specifier, all matching
1076 streams are copied to.
1078 @item @var{c}:@var{chapter_index}
1079 per-chapter metadata. @var{chapter_index} is the zero-based chapter index.
1081 @item @var{p}:@var{program_index}
1082 per-program metadata. @var{program_index} is the zero-based program index.
1084 If metadata specifier is omitted, it defaults to global.
1086 By default, global metadata is copied from the first input file,
1087 per-stream and per-chapter metadata is copied along with streams/chapters. These
1088 default mappings are disabled by creating any mapping of the relevant type. A negative
1089 file index can be used to create a dummy mapping that just disables automatic copying.
1091 For example to copy metadata from the first stream of the input file to global metadata
1094 ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3
1097 To do the reverse, i.e. copy global metadata to all audio streams:
1099 ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv
1101 Note that simple @code{0} would work as well in this example, since global
1102 metadata is assumed by default.
1104 @item -map_chapters @var{input_file_index} (@emph{output})
1105 Copy chapters from input file with index @var{input_file_index} to the next
1106 output file. If no chapter mapping is specified, then chapters are copied from
1107 the first input file with at least one chapter. Use a negative file index to
1108 disable any chapter copying.
1110 @item -benchmark (@emph{global})
1111 Show benchmarking information at the end of an encode.
1112 Shows CPU time used and maximum memory consumption.
1113 Maximum memory consumption is not supported on all systems,
1114 it will usually display as 0 if not supported.
1115 @item -benchmark_all (@emph{global})
1116 Show benchmarking information during the encode.
1117 Shows CPU time used in various steps (audio/video encode/decode).
1118 @item -timelimit @var{duration} (@emph{global})
1119 Exit after ffmpeg has been running for @var{duration} seconds.
1120 @item -dump (@emph{global})
1121 Dump each input packet to stderr.
1122 @item -hex (@emph{global})
1123 When dumping packets, also dump the payload.
1124 @item -re (@emph{input})
1125 Read input at native frame rate. Mainly used to simulate a grab device,
1126 or live input stream (e.g. when reading from a file). Should not be used
1127 with actual grab devices or live input streams (where it can cause packet
1129 By default @command{ffmpeg} attempts to read the input(s) as fast as possible.
1130 This option will slow down the reading of the input(s) to the native frame rate
1131 of the input(s). It is useful for real-time output (e.g. live streaming).
1133 Loop over the input stream. Currently it works only for image
1134 streams. This option is used for automatic FFserver testing.
1135 This option is deprecated, use -loop 1.
1136 @item -loop_output @var{number_of_times}
1137 Repeatedly loop output for formats that support looping such as animated GIF
1138 (0 will loop the output infinitely).
1139 This option is deprecated, use -loop.
1140 @item -vsync @var{parameter}
1142 For compatibility reasons old values can be specified as numbers.
1143 Newly added values will have to be specified as strings always.
1146 @item 0, passthrough
1147 Each frame is passed with its timestamp from the demuxer to the muxer.
1149 Frames will be duplicated and dropped to achieve exactly the requested
1150 constant frame rate.
1152 Frames are passed through with their timestamp or dropped so as to
1153 prevent 2 frames from having the same timestamp.
1155 As passthrough but destroys all timestamps, making the muxer generate
1156 fresh timestamps based on frame-rate.
1158 Chooses between 1 and 2 depending on muxer capabilities. This is the
1162 Note that the timestamps may be further modified by the muxer, after this.
1163 For example, in the case that the format option @option{avoid_negative_ts}
1166 With -map you can select from which stream the timestamps should be
1167 taken. You can leave either video or audio unchanged and sync the
1168 remaining stream(s) to the unchanged one.
1170 @item -frame_drop_threshold @var{parameter}
1171 Frame drop threshold, which specifies how much behind video frames can
1172 be before they are dropped. In frame rate units, so 1.0 is one frame.
1173 The default is -1.1. One possible usecase is to avoid framedrops in case
1174 of noisy timestamps or to increase frame drop precision in case of exact
1177 @item -async @var{samples_per_second}
1178 Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
1179 the parameter is the maximum samples per second by which the audio is changed.
1180 -async 1 is a special case where only the start of the audio stream is corrected
1181 without any later correction.
1183 Note that the timestamps may be further modified by the muxer, after this.
1184 For example, in the case that the format option @option{avoid_negative_ts}
1187 This option has been deprecated. Use the @code{aresample} audio filter instead.
1190 Do not process input timestamps, but keep their values without trying
1191 to sanitize them. In particular, do not remove the initial start time
1194 Note that, depending on the @option{vsync} option or on specific muxer
1195 processing (e.g. in case the format option @option{avoid_negative_ts}
1196 is enabled) the output timestamps may mismatch with the input
1197 timestamps even when this option is selected.
1199 @item -start_at_zero
1200 When used with @option{copyts}, shift input timestamps so they start at zero.
1202 This means that using e.g. @code{-ss 50} will make output timestamps start at
1203 50 seconds, regardless of what timestamp the input file started at.
1205 @item -copytb @var{mode}
1206 Specify how to set the encoder timebase when stream copying. @var{mode} is an
1207 integer numeric value, and can assume one of the following values:
1211 Use the demuxer timebase.
1213 The time base is copied to the output encoder from the corresponding input
1214 demuxer. This is sometimes required to avoid non monotonically increasing
1215 timestamps when copying video streams with variable frame rate.
1218 Use the decoder timebase.
1220 The time base is copied to the output encoder from the corresponding input
1224 Try to make the choice automatically, in order to generate a sane output.
1227 Default value is -1.
1229 @item -enc_time_base[:@var{stream_specifier}] @var{timebase} (@emph{output,per-stream})
1230 Set the encoder timebase. @var{timebase} is a floating point number,
1231 and can assume one of the following values:
1235 Assign a default value according to the media type.
1237 For video - use 1/framerate, for audio - use 1/samplerate.
1240 Use the input stream timebase when possible.
1242 If an input stream is not available, the default timebase will be used.
1245 Use the provided number as the timebase.
1247 This field can be provided as a ratio of two integers (e.g. 1:24, 1:48000)
1248 or as a floating point number (e.g. 0.04166, 2.0833e-5)
1253 @item -bitexact (@emph{input/output})
1254 Enable bitexact mode for (de)muxer and (de/en)coder
1255 @item -shortest (@emph{output})
1256 Finish encoding when the shortest input stream ends.
1257 @item -dts_delta_threshold
1258 Timestamp discontinuity delta threshold.
1259 @item -muxdelay @var{seconds} (@emph{input})
1260 Set the maximum demux-decode delay.
1261 @item -muxpreload @var{seconds} (@emph{input})
1262 Set the initial demux-decode delay.
1263 @item -streamid @var{output-stream-index}:@var{new-value} (@emph{output})
1264 Assign a new stream-id value to an output stream. This option should be
1265 specified prior to the output filename to which it applies.
1266 For the situation where multiple output files exist, a streamid
1267 may be reassigned to a different value.
1269 For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for
1270 an output mpegts file:
1272 ffmpeg -i inurl -streamid 0:33 -streamid 1:36 out.ts
1275 @item -bsf[:@var{stream_specifier}] @var{bitstream_filters} (@emph{output,per-stream})
1276 Set bitstream filters for matching streams. @var{bitstream_filters} is
1277 a comma-separated list of bitstream filters. Use the @code{-bsfs} option
1278 to get the list of bitstream filters.
1280 ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264
1283 ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt
1286 @item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{input/output,per-stream})
1287 Force a tag/fourcc for matching streams.
1289 @item -timecode @var{hh}:@var{mm}:@var{ss}SEP@var{ff}
1290 Specify Timecode for writing. @var{SEP} is ':' for non drop timecode and ';'
1293 ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg
1296 @anchor{filter_complex_option}
1297 @item -filter_complex @var{filtergraph} (@emph{global})
1298 Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
1299 outputs. For simple graphs -- those with one input and one output of the same
1300 type -- see the @option{-filter} options. @var{filtergraph} is a description of
1301 the filtergraph, as described in the ``Filtergraph syntax'' section of the
1302 ffmpeg-filters manual.
1304 Input link labels must refer to input streams using the
1305 @code{[file_index:stream_specifier]} syntax (i.e. the same as @option{-map}
1306 uses). If @var{stream_specifier} matches multiple streams, the first one will be
1307 used. An unlabeled input will be connected to the first unused input stream of
1310 Output link labels are referred to with @option{-map}. Unlabeled outputs are
1311 added to the first output file.
1313 Note that with this option it is possible to use only lavfi sources without
1316 For example, to overlay an image over video
1318 ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
1321 Here @code{[0:v]} refers to the first video stream in the first input file,
1322 which is linked to the first (main) input of the overlay filter. Similarly the
1323 first video stream in the second input is linked to the second (overlay) input
1326 Assuming there is only one video stream in each input file, we can omit input
1327 labels, so the above is equivalent to
1329 ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map
1333 Furthermore we can omit the output label and the single output from the filter
1334 graph will be added to the output file automatically, so we can simply write
1336 ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv
1339 To generate 5 seconds of pure red video using lavfi @code{color} source:
1341 ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv
1344 @item -filter_complex_threads @var{nb_threads} (@emph{global})
1345 Defines how many threads are used to process a filter_complex graph.
1346 Similar to filter_threads but used for @code{-filter_complex} graphs only.
1347 The default is the number of available CPUs.
1349 @item -lavfi @var{filtergraph} (@emph{global})
1350 Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
1351 outputs. Equivalent to @option{-filter_complex}.
1353 @item -filter_complex_script @var{filename} (@emph{global})
1354 This option is similar to @option{-filter_complex}, the only difference is that
1355 its argument is the name of the file from which a complex filtergraph
1356 description is to be read.
1358 @item -accurate_seek (@emph{input})
1359 This option enables or disables accurate seeking in input files with the
1360 @option{-ss} option. It is enabled by default, so seeking is accurate when
1361 transcoding. Use @option{-noaccurate_seek} to disable it, which may be useful
1362 e.g. when copying some streams and transcoding the others.
1364 @item -seek_timestamp (@emph{input})
1365 This option enables or disables seeking by timestamp in input files with the
1366 @option{-ss} option. It is disabled by default. If enabled, the argument
1367 to the @option{-ss} option is considered an actual timestamp, and is not
1368 offset by the start time of the file. This matters only for files which do
1369 not start from timestamp 0, such as transport streams.
1371 @item -thread_queue_size @var{size} (@emph{input})
1372 This option sets the maximum number of queued packets when reading from the
1373 file or device. With low latency / high rate live streams, packets may be
1374 discarded if they are not read in a timely manner; raising this value can
1377 @item -override_ffserver (@emph{global})
1378 Overrides the input specifications from @command{ffserver}. Using this
1379 option you can map any input stream to @command{ffserver} and control
1380 many aspects of the encoding from @command{ffmpeg}. Without this
1381 option @command{ffmpeg} will transmit to @command{ffserver} what is
1382 requested by @command{ffserver}.
1384 The option is intended for cases where features are needed that cannot be
1385 specified to @command{ffserver} but can be to @command{ffmpeg}.
1387 @item -sdp_file @var{file} (@emph{global})
1388 Print sdp information for an output stream to @var{file}.
1389 This allows dumping sdp information when at least one output isn't an
1390 rtp stream. (Requires at least one of the output formats to be rtp).
1392 @item -discard (@emph{input})
1393 Allows discarding specific streams or frames of streams at the demuxer.
1394 Not all demuxers support this.
1401 Default, which discards no frames.
1404 Discard all non-reference frames.
1407 Discard all bidirectional frames.
1410 Discard all frames excepts keyframes.
1416 @item -abort_on @var{flags} (@emph{global})
1417 Stop and abort on various conditions. The following flags are available:
1421 No packets were passed to the muxer, the output is empty.
1424 @item -xerror (@emph{global})
1425 Stop and exit on error
1427 @item -max_muxing_queue_size @var{packets} (@emph{output,per-stream})
1428 When transcoding audio and/or video streams, ffmpeg will not begin writing into
1429 the output until it has one packet for each such stream. While waiting for that
1430 to happen, packets for other streams are buffered. This option sets the size of
1431 this buffer, in packets, for the matching output stream.
1433 The default value of this option should be high enough for most uses, so only
1434 touch this option if you are sure that you need it.
1438 As a special exception, you can use a bitmap subtitle stream as input: it
1439 will be converted into a video with the same size as the largest video in
1440 the file, or 720x576 if no video is present. Note that this is an
1441 experimental and temporary solution. It will be removed once libavfilter has
1442 proper support for subtitles.
1444 For example, to hardcode subtitles on top of a DVB-T recording stored in
1445 MPEG-TS format, delaying the subtitles by 1 second:
1447 ffmpeg -i input.ts -filter_complex \
1448 '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
1449 -sn -map '#0x2dc' output.mkv
1451 (0x2d0, 0x2dc and 0x2ef are the MPEG-TS PIDs of respectively the video,
1452 audio and subtitles streams; 0:0, 0:3 and 0:7 would have worked too)
1454 @section Preset files
1455 A preset file contains a sequence of @var{option}=@var{value} pairs,
1456 one for each line, specifying a sequence of options which would be
1457 awkward to specify on the command line. Lines starting with the hash
1458 ('#') character are ignored and are used to provide comments. Check
1459 the @file{presets} directory in the FFmpeg source tree for examples.
1461 There are two types of preset files: ffpreset and avpreset files.
1463 @subsection ffpreset files
1464 ffpreset files are specified with the @code{vpre}, @code{apre},
1465 @code{spre}, and @code{fpre} options. The @code{fpre} option takes the
1466 filename of the preset instead of a preset name as input and can be
1467 used for any kind of codec. For the @code{vpre}, @code{apre}, and
1468 @code{spre} options, the options specified in a preset file are
1469 applied to the currently selected codec of the same type as the preset
1472 The argument passed to the @code{vpre}, @code{apre}, and @code{spre}
1473 preset options identifies the preset file to use according to the
1476 First ffmpeg searches for a file named @var{arg}.ffpreset in the
1477 directories @file{$FFMPEG_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
1478 the datadir defined at configuration time (usually @file{PREFIX/share/ffmpeg})
1479 or in a @file{ffpresets} folder along the executable on win32,
1480 in that order. For example, if the argument is @code{libvpx-1080p}, it will
1481 search for the file @file{libvpx-1080p.ffpreset}.
1483 If no such file is found, then ffmpeg will search for a file named
1484 @var{codec_name}-@var{arg}.ffpreset in the above-mentioned
1485 directories, where @var{codec_name} is the name of the codec to which
1486 the preset file options will be applied. For example, if you select
1487 the video codec with @code{-vcodec libvpx} and use @code{-vpre 1080p},
1488 then it will search for the file @file{libvpx-1080p.ffpreset}.
1490 @subsection avpreset files
1491 avpreset files are specified with the @code{pre} option. They work similar to
1492 ffpreset files, but they only allow encoder- specific options. Therefore, an
1493 @var{option}=@var{value} pair specifying an encoder cannot be used.
1495 When the @code{pre} option is specified, ffmpeg will look for files with the
1496 suffix .avpreset in the directories @file{$AVCONV_DATADIR} (if set), and
1497 @file{$HOME/.avconv}, and in the datadir defined at configuration time (usually
1498 @file{PREFIX/share/ffmpeg}), in that order.
1500 First ffmpeg searches for a file named @var{codec_name}-@var{arg}.avpreset in
1501 the above-mentioned directories, where @var{codec_name} is the name of the codec
1502 to which the preset file options will be applied. For example, if you select the
1503 video codec with @code{-vcodec libvpx} and use @code{-pre 1080p}, then it will
1504 search for the file @file{libvpx-1080p.avpreset}.
1506 If no such file is found, then ffmpeg will search for a file named
1507 @var{arg}.avpreset in the same directories.
1512 @c man begin EXAMPLES
1514 @section Video and Audio grabbing
1516 If you specify the input format and device then ffmpeg can grab video
1520 ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
1523 Or with an ALSA audio source (mono input, card id 1) instead of OSS:
1525 ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg
1528 Note that you must activate the right video source and channel before
1529 launching ffmpeg with any TV viewer such as
1530 @uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also
1531 have to set the audio recording levels correctly with a
1534 @section X11 grabbing
1536 Grab the X11 display with ffmpeg via
1539 ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0 /tmp/out.mpg
1542 0.0 is display.screen number of your X11 server, same as
1543 the DISPLAY environment variable.
1546 ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0+10,20 /tmp/out.mpg
1549 0.0 is display.screen number of your X11 server, same as the DISPLAY environment
1550 variable. 10 is the x-offset and 20 the y-offset for the grabbing.
1552 @section Video and Audio file format conversion
1554 Any supported file format and protocol can serve as input to ffmpeg:
1559 You can use YUV files as input:
1562 ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
1565 It will use the files:
1567 /tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
1568 /tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
1571 The Y files use twice the resolution of the U and V files. They are
1572 raw files, without header. They can be generated by all decent video
1573 decoders. You must specify the size of the image with the @option{-s} option
1574 if ffmpeg cannot guess it.
1577 You can input from a raw YUV420P file:
1580 ffmpeg -i /tmp/test.yuv /tmp/out.avi
1583 test.yuv is a file containing raw YUV planar data. Each frame is composed
1584 of the Y plane followed by the U and V planes at half vertical and
1585 horizontal resolution.
1588 You can output to a raw YUV420P file:
1591 ffmpeg -i mydivx.avi hugefile.yuv
1595 You can set several input files and output files:
1598 ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
1601 Converts the audio file a.wav and the raw YUV video file a.yuv
1605 You can also do audio and video conversions at the same time:
1608 ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
1611 Converts a.wav to MPEG audio at 22050 Hz sample rate.
1614 You can encode to several formats at the same time and define a
1615 mapping from input stream to output streams:
1618 ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2
1621 Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
1622 file:index' specifies which input stream is used for each output
1623 stream, in the order of the definition of output streams.
1626 You can transcode decrypted VOBs:
1629 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
1632 This is a typical DVD ripping example; the input is a VOB file, the
1633 output an AVI file with MPEG-4 video and MP3 audio. Note that in this
1634 command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
1635 GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
1636 input video. Furthermore, the audio stream is MP3-encoded so you need
1637 to enable LAME support by passing @code{--enable-libmp3lame} to configure.
1638 The mapping is particularly useful for DVD transcoding
1639 to get the desired audio language.
1641 NOTE: To see the supported input formats, use @code{ffmpeg -demuxers}.
1644 You can extract images from a video, or create a video from many images:
1646 For extracting images from a video:
1648 ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
1651 This will extract one video frame per second from the video and will
1652 output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg},
1653 etc. Images will be rescaled to fit the new WxH values.
1655 If you want to extract just a limited number of frames, you can use the
1656 above command in combination with the @code{-frames:v} or @code{-t} option,
1657 or in combination with -ss to start extracting from a certain point in time.
1659 For creating a video from many images:
1661 ffmpeg -f image2 -framerate 12 -i foo-%03d.jpeg -s WxH foo.avi
1664 The syntax @code{foo-%03d.jpeg} specifies to use a decimal number
1665 composed of three digits padded with zeroes to express the sequence
1666 number. It is the same syntax supported by the C printf function, but
1667 only formats accepting a normal integer are suitable.
1669 When importing an image sequence, -i also supports expanding
1670 shell-like wildcard patterns (globbing) internally, by selecting the
1671 image2-specific @code{-pattern_type glob} option.
1673 For example, for creating a video from filenames matching the glob pattern
1676 ffmpeg -f image2 -pattern_type glob -framerate 12 -i 'foo-*.jpeg' -s WxH foo.avi
1680 You can put many streams of the same type in the output:
1683 ffmpeg -i test1.avi -i test2.avi -map 1:1 -map 1:0 -map 0:1 -map 0:0 -c copy -y test12.nut
1686 The resulting output file @file{test12.nut} will contain the first four streams
1687 from the input files in reverse order.
1690 To force CBR video output:
1692 ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
1696 The four options lmin, lmax, mblmin and mblmax use 'lambda' units,
1697 but you may use the QP2LAMBDA constant to easily convert from 'q' units:
1699 ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
1705 @include config.texi
1707 @ifset config-avutil
1710 @ifset config-avcodec
1711 @include codecs.texi
1712 @include bitstream_filters.texi
1714 @ifset config-avformat
1715 @include formats.texi
1716 @include protocols.texi
1718 @ifset config-avdevice
1719 @include devices.texi
1721 @ifset config-swresample
1722 @include resampler.texi
1724 @ifset config-swscale
1725 @include scaler.texi
1727 @ifset config-avfilter
1728 @include filters.texi
1736 @url{ffmpeg.html,ffmpeg}
1738 @ifset config-not-all
1739 @url{ffmpeg-all.html,ffmpeg-all},
1741 @url{ffplay.html,ffplay}, @url{ffprobe.html,ffprobe}, @url{ffserver.html,ffserver},
1742 @url{ffmpeg-utils.html,ffmpeg-utils},
1743 @url{ffmpeg-scaler.html,ffmpeg-scaler},
1744 @url{ffmpeg-resampler.html,ffmpeg-resampler},
1745 @url{ffmpeg-codecs.html,ffmpeg-codecs},
1746 @url{ffmpeg-bitstream-filters.html,ffmpeg-bitstream-filters},
1747 @url{ffmpeg-formats.html,ffmpeg-formats},
1748 @url{ffmpeg-devices.html,ffmpeg-devices},
1749 @url{ffmpeg-protocols.html,ffmpeg-protocols},
1750 @url{ffmpeg-filters.html,ffmpeg-filters}
1757 @ifset config-not-all
1760 ffplay(1), ffprobe(1), ffserver(1),
1761 ffmpeg-utils(1), ffmpeg-scaler(1), ffmpeg-resampler(1),
1762 ffmpeg-codecs(1), ffmpeg-bitstream-filters(1), ffmpeg-formats(1),
1763 ffmpeg-devices(1), ffmpeg-protocols(1), ffmpeg-filters(1)
1766 @include authors.texi
1771 @settitle ffmpeg video converter