1 \input texinfo @c -*- texinfo -*-
3 @settitle ffmpeg Documentation
5 @center @titlefont{ffmpeg Documentation}
14 ffmpeg [@var{global_options}] @{[@var{input_file_options}] -i @file{input_file}@} ... @{[@var{output_file_options}] @file{output_file}@} ...
17 @c man begin DESCRIPTION
19 ffmpeg is a very fast video and audio converter that can also grab from
20 a live audio/video source. It can also convert between arbitrary sample
21 rates and resize video on the fly with a high quality polyphase filter.
23 ffmpeg reads from an arbitrary number of input "files" (which can be regular
24 files, pipes, network streams, grabbing devices, etc.), specified by the
25 @code{-i} option, and writes to an arbitrary number of output "files", which are
26 specified by a plain output filename. Anything found on the command line which
27 cannot be interpreted as an option is considered to be an output filename.
29 Each input or output file can in principle contain any number of streams of
30 different types (video/audio/subtitle/attachment/data). Allowed number and/or
31 types of streams can be limited by the container format. Selecting, which
32 streams from which inputs go into output, is done either automatically or with
33 the @code{-map} option (see the Stream selection chapter).
35 To refer to input files in options, you must use their indices (0-based). E.g.
36 the first input file is @code{0}, the second is @code{1} etc. Similarly, streams
37 within a file are referred to by their indices. E.g. @code{2:3} refers to the
38 fourth stream in the third input file. See also the Stream specifiers chapter.
40 As a general rule, options are applied to the next specified
41 file. Therefore, order is important, and you can have the same
42 option on the command line multiple times. Each occurrence is
43 then applied to the next input or output file.
44 Exceptions from this rule are the global options (e.g. verbosity level),
45 which should be specified first.
47 Do not mix input and output files -- first specify all input files, then all
48 output files. Also do not mix options which belong to different files. All
49 options apply ONLY to the next input or output file and are reset between files.
53 To set the video bitrate of the output file to 64kbit/s:
55 ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi
59 To force the frame rate of the output file to 24 fps:
61 ffmpeg -i input.avi -r 24 output.avi
65 To force the frame rate of the input file (valid for raw formats only)
66 to 1 fps and the frame rate of the output file to 24 fps:
68 ffmpeg -r 1 -i input.m2v -r 24 output.avi
72 The format option may be needed for raw input files.
74 @c man end DESCRIPTION
76 @chapter Detailed description
77 @c man begin DETAILED DESCRIPTION
79 The transcoding process in @command{ffmpeg} for each output can be described by
80 the following diagram:
83 _______ ______________ _________ ______________ ________
85 | input | demuxer | encoded data | decoder | decoded | encoder | encoded data | muxer | output |
86 | file | ---------> | packets | ---------> | frames | ---------> | packets | -------> | file |
87 |_______| |______________| |_________| |______________| |________|
91 @command{ffmpeg} calls the libavformat library (containing demuxers) to read
92 input files and get packets containing encoded data from them. When there are
93 multiple input files, @command{ffmpeg} tries to keep them synchronized by
94 tracking lowest timestamp on any active input stream.
96 Encoded packets are then passed to the decoder (unless streamcopy is selected
97 for the stream, see further for a description). The decoder produces
98 uncompressed frames (raw video/PCM audio/...) which can be processed further by
99 filtering (see next section). After filtering the frames are passed to the
100 encoder, which encodes them and outputs encoded packets again. Finally those are
101 passed to the muxer, which writes the encoded packets to the output file.
104 Before encoding, @command{ffmpeg} can process raw audio and video frames using
105 filters from the libavfilter library. Several chained filters form a filter
106 graph. @command{ffmpeg} distinguishes between two types of filtergraphs -
109 @subsection Simple filtergraphs
110 Simple filtergraphs are those that have exactly one input and output, both of
111 the same type. In the above diagram they can be represented by simply inserting
112 an additional step between decoding and encoding:
115 _________ __________ ______________
117 | decoded | simple filtergraph | filtered | encoder | encoded data |
118 | frames | -------------------> | frames | ---------> | packets |
119 |_________| |__________| |______________|
123 Simple filtergraphs are configured with the per-stream @option{-filter} option
124 (with @option{-vf} and @option{-af} aliases for video and audio respectively).
125 A simple filtergraph for video can look for example like this:
128 _______ _____________ _______ _____ ________
130 | input | ---> | deinterlace | ---> | scale | ---> | fps | ---> | output |
131 |_______| |_____________| |_______| |_____| |________|
135 Note that some filters change frame properties but not frame contents. E.g. the
136 @code{fps} filter in the example above changes number of frames, but does not
137 touch the frame contents. Another example is the @code{setpts} filter, which
138 only sets timestamps and otherwise passes the frames unchanged.
140 @subsection Complex filtergraphs
141 Complex filtergraphs are those which cannot be described as simply a linear
142 processing chain applied to one stream. This is the case e.g. when the graph has
143 more than one input and/or output, or when output stream type is different from
144 input. They can be represented with the following diagram:
149 | input 0 |\ __________
151 \ _________ /| output 0 |
153 _________ \| complex | /
155 | input 1 |---->| filter |\
156 |_________| | | \ __________
159 _________ / |_________| |__________|
166 Complex filtergraphs are configured with the @option{-filter_complex} option.
167 Note that this option is global, since a complex filtergraph by its nature
168 cannot be unambiguously associated with a single stream or file.
170 A trivial example of a complex filtergraph is the @code{overlay} filter, which
171 has two video inputs and one video output, containing one video overlaid on top
172 of the other. Its audio counterpart is the @code{amix} filter.
175 Stream copy is a mode selected by supplying the @code{copy} parameter to the
176 @option{-codec} option. It makes @command{ffmpeg} omit the decoding and encoding
177 step for the specified stream, so it does only demuxing and muxing. It is useful
178 for changing the container format or modifying container-level metadata. The
179 diagram above will in this case simplify to this:
182 _______ ______________ ________
184 | input | demuxer | encoded data | muxer | output |
185 | file | ---------> | packets | -------> | file |
186 |_______| |______________| |________|
190 Since there is no decoding or encoding, it is very fast and there is no quality
191 loss. However it might not work in some cases because of many factors. Applying
192 filters is obviously also impossible, since filters work on uncompressed data.
194 @c man end DETAILED DESCRIPTION
196 @chapter Stream selection
197 @c man begin STREAM SELECTION
199 By default ffmpeg includes only one stream of each type (video, audio, subtitle)
200 present in the input files and adds them to each output file. It picks the
201 "best" of each based upon the following criteria; for video it is the stream
202 with the highest resolution, for audio the stream with the most channels, for
203 subtitle it's the first subtitle stream. In the case where several streams of
204 the same type rate equally, the lowest numbered stream is chosen.
206 You can disable some of those defaults by using @code{-vn/-an/-sn} options. For
207 full manual control, use the @code{-map} option, which disables the defaults just
210 @c man end STREAM SELECTION
215 @include avtools-common-opts.texi
217 @section Main options
221 @item -f @var{fmt} (@emph{input/output})
222 Force input or output file format. The format is normally auto detected for input
223 files and guessed from file extension for output files, so this option is not
224 needed in most cases.
226 @item -i @var{filename} (@emph{input})
229 @item -y (@emph{global})
230 Overwrite output files without asking.
232 @item -n (@emph{global})
233 Do not overwrite output files but exit if file exists.
235 @item -c[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
236 @itemx -codec[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
237 Select an encoder (when used before an output file) or a decoder (when used
238 before an input file) for one or more streams. @var{codec} is the name of a
239 decoder/encoder or a special value @code{copy} (output only) to indicate that
240 the stream is not to be re-encoded.
244 ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT
246 encodes all video streams with libx264 and copies all audio streams.
248 For each stream, the last matching @code{c} option is applied, so
250 ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT
252 will copy all the streams except the second video, which will be encoded with
253 libx264, and the 138th audio, which will be encoded with libvorbis.
255 @item -t @var{duration} (@emph{output})
256 Stop writing the output after its duration reaches @var{duration}.
257 @var{duration} may be a number in seconds, or in @code{hh:mm:ss[.xxx]} form.
259 @item -fs @var{limit_size} (@emph{output})
260 Set the file size limit, expressed in bytes.
262 @item -ss @var{position} (@emph{input/output})
263 When used as an input option (before @code{-i}), seeks in this input file to
264 @var{position}. When used as an output option (before an output filename),
265 decodes but discards input until the timestamps reach @var{position}. This is
266 slower, but more accurate.
268 @var{position} may be either in seconds or in @code{hh:mm:ss[.xxx]} form.
270 @item -itsoffset @var{offset} (@emph{input})
271 Set the input time offset in seconds.
272 @code{[-]hh:mm:ss[.xxx]} syntax is also supported.
273 The offset is added to the timestamps of the input files.
274 Specifying a positive offset means that the corresponding
275 streams are delayed by @var{offset} seconds.
277 @item -timestamp @var{time} (@emph{output})
278 Set the recording timestamp in the container.
279 The syntax for @var{time} is:
281 now|([(YYYY-MM-DD|YYYYMMDD)[T|t| ]]((HH:MM:SS[.m...])|(HHMMSS[.m...]))[Z|z])
283 If the value is "now" it takes the current time.
284 Time is local time unless 'Z' or 'z' is appended, in which case it is
286 If the year-month-day part is not specified it takes the current
289 @item -metadata[:metadata_specifier] @var{key}=@var{value} (@emph{output,per-metadata})
290 Set a metadata key/value pair.
292 An optional @var{metadata_specifier} may be given to set metadata
293 on streams or chapters. See @code{-map_metadata} documentation for
296 This option overrides metadata set with @code{-map_metadata}. It is
297 also possible to delete metadata by using an empty value.
299 For example, for setting the title in the output file:
301 ffmpeg -i in.avi -metadata title="my title" out.flv
304 To set the language of the first audio stream:
306 ffmpeg -i INPUT -metadata:s:a:1 language=eng OUTPUT
309 @item -target @var{type} (@emph{output})
310 Specify target file type (@code{vcd}, @code{svcd}, @code{dvd}, @code{dv},
311 @code{dv50}). @var{type} may be prefixed with @code{pal-}, @code{ntsc-} or
312 @code{film-} to use the corresponding standard. All the format options
313 (bitrate, codecs, buffer sizes) are then set automatically. You can just type:
316 ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
319 Nevertheless you can specify additional options as long as you know
320 they do not conflict with the standard, as in:
323 ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
326 @item -dframes @var{number} (@emph{output})
327 Set the number of data frames to record. This is an alias for @code{-frames:d}.
329 @item -frames[:@var{stream_specifier}] @var{framecount} (@emph{output,per-stream})
330 Stop writing to the stream after @var{framecount} frames.
332 @item -q[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
333 @itemx -qscale[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
334 Use fixed quality scale (VBR). The meaning of @var{q} is
337 @anchor{filter_option}
338 @item -filter[:@var{stream_specifier}] @var{filter_graph} (@emph{output,per-stream})
339 Create the filter graph specified by @var{filter_graph} and use it to
342 @var{filter_graph} is a description of the filter graph to apply to
343 the stream, and must have a single input and a single output of the
344 same type of the stream. In the filter graph, the input is associated
345 to the label @code{in}, and the output to the label @code{out}. See
346 the ffmpeg-filters manual for more information about the filtergraph
349 See the @ref{filter_complex_option,,-filter_complex option} if you
350 want to create filter graphs with multiple inputs and/or outputs.
352 @item -pre[:@var{stream_specifier}] @var{preset_name} (@emph{output,per-stream})
353 Specify the preset for matching stream(s).
355 @item -stats (@emph{global})
356 Print encoding progress/statistics. On by default.
358 @item -progress @var{url} (@emph{global})
359 Send program-friendly progress information to @var{url}.
361 Progress information is written approximately every second and at the end of
362 the encoding process. It is made of "@var{key}=@var{value}" lines. @var{key}
363 consists of only alphanumeric characters. The last key of a sequence of
364 progress information is always "progress".
367 Enable interaction on standard input. On by default unless standard input is
368 used as an input. To explicitly disable interaction you need to specify
371 Disabling interaction on standard input is useful, for example, if
372 ffmpeg is in the background process group. Roughly the same result can
373 be achieved with @code{ffmpeg ... < /dev/null} but it requires a
376 @item -debug_ts (@emph{global})
377 Print timestamp information. It is off by default. This option is
378 mostly useful for testing and debugging purposes, and the output
379 format may change from one version to another, so it should not be
380 employed by portable scripts.
382 See also the option @code{-fdebug ts}.
384 @item -attach @var{filename} (@emph{output})
385 Add an attachment to the output file. This is supported by a few formats
386 like Matroska for e.g. fonts used in rendering subtitles. Attachments
387 are implemented as a specific type of stream, so this option will add
388 a new stream to the file. It is then possible to use per-stream options
389 on this stream in the usual way. Attachment streams created with this
390 option will be created after all the other streams (i.e. those created
391 with @code{-map} or automatic mappings).
393 Note that for Matroska you also have to set the mimetype metadata tag:
395 ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv
397 (assuming that the attachment stream will be third in the output file).
399 @item -dump_attachment[:@var{stream_specifier}] @var{filename} (@emph{input,per-stream})
400 Extract the matching attachment stream into a file named @var{filename}. If
401 @var{filename} is empty, then the value of the @code{filename} metadata tag
404 E.g. to extract the first attachment to a file named 'out.ttf':
406 ffmpeg -dump_attachment:t:0 out.ttf INPUT
408 To extract all attachments to files determined by the @code{filename} tag:
410 ffmpeg -dump_attachment:t "" INPUT
413 Technical note -- attachments are implemented as codec extradata, so this
414 option can actually be used to extract extradata from any stream, not just
419 @section Video Options
422 @item -vframes @var{number} (@emph{output})
423 Set the number of video frames to record. This is an alias for @code{-frames:v}.
424 @item -r[:@var{stream_specifier}] @var{fps} (@emph{input/output,per-stream})
425 Set frame rate (Hz value, fraction or abbreviation).
427 As an input option, ignore any timestamps stored in the file and instead
428 generate timestamps assuming constant frame rate @var{fps}.
430 As an output option, duplicate or drop input frames to achieve constant output
431 frame rate @var{fps}.
433 @item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream})
436 As an input option, this is a shortcut for the @option{video_size} private
437 option, recognized by some demuxers for which the frame size is either not
438 stored in the file or is configurable -- e.g. raw video or video grabbers.
440 As an output option, this inserts the @code{scale} video filter to the
441 @emph{end} of the corresponding filtergraph. Please use the @code{scale} filter
442 directly to insert it at the beginning or some other place.
444 The format is @samp{wxh} (default - same as source).
446 @item -aspect[:@var{stream_specifier}] @var{aspect} (@emph{output,per-stream})
447 Set the video display aspect ratio specified by @var{aspect}.
449 @var{aspect} can be a floating point number string, or a string of the
450 form @var{num}:@var{den}, where @var{num} and @var{den} are the
451 numerator and denominator of the aspect ratio. For example "4:3",
452 "16:9", "1.3333", and "1.7777" are valid argument values.
454 @item -vn (@emph{output})
455 Disable video recording.
457 @item -vcodec @var{codec} (@emph{output})
458 Set the video codec. This is an alias for @code{-codec:v}.
460 @item -pass[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
461 Select the pass number (1 or 2). It is used to do two-pass
462 video encoding. The statistics of the video are recorded in the first
463 pass into a log file (see also the option -passlogfile),
464 and in the second pass that log file is used to generate the video
465 at the exact requested bitrate.
466 On pass 1, you may just deactivate audio and set output to null,
467 examples for Windows and Unix:
469 ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
470 ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null
473 @item -passlogfile[:@var{stream_specifier}] @var{prefix} (@emph{output,per-stream})
474 Set two-pass log file name prefix to @var{prefix}, the default file name
475 prefix is ``ffmpeg2pass''. The complete file name will be
476 @file{PREFIX-N.log}, where N is a number specific to the output
479 @item -vlang @var{code}
480 Set the ISO 639 language code (3 letters) of the current video stream.
482 @item -vf @var{filter_graph} (@emph{output})
483 Create the filter graph specified by @var{filter_graph} and use it to
486 This is an alias for @code{-filter:v}, see the @ref{filter_option,,-filter option}.
489 @section Advanced Video Options
492 @item -pix_fmt[:@var{stream_specifier}] @var{format} (@emph{input/output,per-stream})
493 Set pixel format. Use @code{-pix_fmts} to show all the supported
495 If the selected pixel format can not be selected, ffmpeg will print a
496 warning and select the best pixel format supported by the encoder.
497 If @var{pix_fmt} is prefixed by a @code{+}, ffmpeg will exit with an error
498 if the requested pixel format can not be selected, and automatic conversions
499 inside filter graphs are disabled.
500 If @var{pix_fmt} is a single @code{+}, ffmpeg selects the same pixel format
501 as the input (or graph output) and automatic conversions are disabled.
503 @item -sws_flags @var{flags} (@emph{input/output})
508 @item -rc_override[:@var{stream_specifier}] @var{override} (@emph{output,per-stream})
509 Rate control override for specific intervals, formatted as "int,int,int"
510 list separated with slashes. Two first values are the beginning and
511 end frame numbers, last one is quantizer to use if positive, or quality
515 Deinterlace pictures.
516 This option is deprecated since the deinterlacing is very low quality.
517 Use the yadif filter with @code{-filter:v yadif}.
519 Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
520 Use this option if your input file is interlaced and you want
521 to keep the interlaced format for minimum losses.
522 The alternative is to deinterlace the input stream with
523 @option{-deinterlace}, but deinterlacing introduces losses.
525 Calculate PSNR of compressed frames.
527 Dump video coding statistics to @file{vstats_HHMMSS.log}.
528 @item -vstats_file @var{file}
529 Dump video coding statistics to @var{file}.
530 @item -top[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
531 top=1/bottom=0/auto=-1 field first
532 @item -dc @var{precision}
534 @item -vtag @var{fourcc/tag} (@emph{output})
535 Force video tag/fourcc. This is an alias for @code{-tag:v}.
536 @item -qphist (@emph{global})
538 @item -vbsf @var{bitstream_filter}
541 @item -force_key_frames[:@var{stream_specifier}] @var{time}[,@var{time}...] (@emph{output,per-stream})
542 @item -force_key_frames[:@var{stream_specifier}] expr:@var{expr} (@emph{output,per-stream})
543 Force key frames at the specified timestamps, more precisely at the first
544 frames after each specified time.
546 If the argument is prefixed with @code{expr:}, the string @var{expr}
547 is interpreted like an expression and is evaluated for each frame. A
548 key frame is forced in case the evaluation is non-zero.
550 If one of the times is "@code{chapters}[@var{delta}]", it is expanded into
551 the time of the beginning of all chapters in the file, shifted by
552 @var{delta}, expressed as a time in seconds.
553 This option can be useful to ensure that a seek point is present at a
554 chapter mark or any other designated place in the output file.
556 For example, to insert a key frame at 5 minutes, plus key frames 0.1 second
557 before the beginning of every chapter:
559 -force_key_frames 0:05:00,chapters-0.1
562 The expression in @var{expr} can contain the following constants:
565 the number of current processed frame, starting from 0
567 the number of forced frames
569 the number of the previous forced frame, it is @code{NAN} when no
570 keyframe was forced yet
572 the time of the previous forced frame, it is @code{NAN} when no
573 keyframe was forced yet
575 the time of the current processed frame
578 For example to force a key frame every 5 seconds, you can specify:
580 -force_key_frames expr:gte(t,n_forced*5)
583 To force a key frame 5 seconds after the time of the last forced one,
584 starting from second 13:
586 -force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5))
589 Note that forcing too many keyframes is very harmful for the lookahead
590 algorithms of certain encoders: using fixed-GOP options or similar
591 would be more efficient.
593 @item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream})
594 When doing stream copy, copy also non-key frames found at the
598 @section Audio Options
601 @item -aframes @var{number} (@emph{output})
602 Set the number of audio frames to record. This is an alias for @code{-frames:a}.
603 @item -ar[:@var{stream_specifier}] @var{freq} (@emph{input/output,per-stream})
604 Set the audio sampling frequency. For output streams it is set by
605 default to the frequency of the corresponding input stream. For input
606 streams this option only makes sense for audio grabbing devices and raw
607 demuxers and is mapped to the corresponding demuxer options.
608 @item -aq @var{q} (@emph{output})
609 Set the audio quality (codec-specific, VBR). This is an alias for -q:a.
610 @item -ac[:@var{stream_specifier}] @var{channels} (@emph{input/output,per-stream})
611 Set the number of audio channels. For output streams it is set by
612 default to the number of input audio channels. For input streams
613 this option only makes sense for audio grabbing devices and raw demuxers
614 and is mapped to the corresponding demuxer options.
615 @item -an (@emph{output})
616 Disable audio recording.
617 @item -acodec @var{codec} (@emph{input/output})
618 Set the audio codec. This is an alias for @code{-codec:a}.
619 @item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream})
620 Set the audio sample format. Use @code{-sample_fmts} to get a list
621 of supported sample formats.
623 @item -af @var{filter_graph} (@emph{output})
624 Create the filter graph specified by @var{filter_graph} and use it to
627 This is an alias for @code{-filter:a}, see the @ref{filter_option,,-filter option}.
630 @section Advanced Audio options:
633 @item -atag @var{fourcc/tag} (@emph{output})
634 Force audio tag/fourcc. This is an alias for @code{-tag:a}.
635 @item -absf @var{bitstream_filter}
637 @item -guess_layout_max @var{channels} (@emph{input,per-stream})
638 If some input channel layout is not known, try to guess only if it
639 corresponds to at most the specified number of channels. For example, 2
640 tells to @command{ffmpeg} to recognize 1 channel as mono and 2 channels as
641 stereo but not 6 channels as 5.1. The default is to always try to guess. Use
642 0 to disable all guessing.
645 @section Subtitle options:
648 @item -slang @var{code}
649 Set the ISO 639 language code (3 letters) of the current subtitle stream.
650 @item -scodec @var{codec} (@emph{input/output})
651 Set the subtitle codec. This is an alias for @code{-codec:s}.
652 @item -sn (@emph{output})
653 Disable subtitle recording.
654 @item -sbsf @var{bitstream_filter}
658 @section Advanced Subtitle options:
662 @item -fix_sub_duration
663 Fix subtitles durations. For each subtitle, wait for the next packet in the
664 same stream and adjust the duration of the first to avoid overlap. This is
665 necessary with some subtitles codecs, especially DVB subtitles, because the
666 duration in the original packet is only a rough estimate and the end is
667 actually marked by an empty subtitle frame. Failing to use this option when
668 necessary can result in exaggerated durations or muxing failures due to
669 non-monotonic timestamps.
671 Note that this option will delay the output of all data until the next
672 subtitle packet is decoded: it may increase memory consumption and latency a
677 @section Advanced options
680 @item -map [-]@var{input_file_id}[:@var{stream_specifier}][,@var{sync_file_id}[:@var{stream_specifier}]] | @var{[linklabel]} (@emph{output})
682 Designate one or more input streams as a source for the output file. Each input
683 stream is identified by the input file index @var{input_file_id} and
684 the input stream index @var{input_stream_id} within the input
685 file. Both indices start at 0. If specified,
686 @var{sync_file_id}:@var{stream_specifier} sets which input stream
687 is used as a presentation sync reference.
689 The first @code{-map} option on the command line specifies the
690 source for output stream 0, the second @code{-map} option specifies
691 the source for output stream 1, etc.
693 A @code{-} character before the stream identifier creates a "negative" mapping.
694 It disables matching streams from already created mappings.
696 An alternative @var{[linklabel]} form will map outputs from complex filter
697 graphs (see the @option{-filter_complex} option) to the output file.
698 @var{linklabel} must correspond to a defined output link label in the graph.
700 For example, to map ALL streams from the first input file to output
702 ffmpeg -i INPUT -map 0 output
705 For example, if you have two audio streams in the first input file,
706 these streams are identified by "0:0" and "0:1". You can use
707 @code{-map} to select which streams to place in an output file. For
710 ffmpeg -i INPUT -map 0:1 out.wav
712 will map the input stream in @file{INPUT} identified by "0:1" to
713 the (single) output stream in @file{out.wav}.
715 For example, to select the stream with index 2 from input file
716 @file{a.mov} (specified by the identifier "0:2"), and stream with
717 index 6 from input @file{b.mov} (specified by the identifier "1:6"),
718 and copy them to the output file @file{out.mov}:
720 ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
723 To select all video and the third audio stream from an input file:
725 ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT
728 To map all the streams except the second audio, use negative mappings
730 ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT
733 Note that using this option disables the default mappings for this output file.
735 @item -map_channel [@var{input_file_id}.@var{stream_specifier}.@var{channel_id}|-1][:@var{output_file_id}.@var{stream_specifier}]
736 Map an audio channel from a given input to an output. If
737 @var{output_file_id}.@var{stream_specifier} is not set, the audio channel will
738 be mapped on all the audio streams.
740 Using "-1" instead of
741 @var{input_file_id}.@var{stream_specifier}.@var{channel_id} will map a muted
744 For example, assuming @var{INPUT} is a stereo audio file, you can switch the
745 two audio channels with the following command:
747 ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT
750 If you want to mute the first channel and keep the second:
752 ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT
755 The order of the "-map_channel" option specifies the order of the channels in
756 the output stream. The output channel layout is guessed from the number of
757 channels mapped (mono if one "-map_channel", stereo if two, etc.). Using "-ac"
758 in combination of "-map_channel" makes the channel gain levels to be updated if
759 input and output channel layouts don't match (for instance two "-map_channel"
760 options and "-ac 6").
762 You can also extract each channel of an input to specific outputs; the following
763 command extracts two channels of the @var{INPUT} audio stream (file 0, stream 0)
764 to the respective @var{OUTPUT_CH0} and @var{OUTPUT_CH1} outputs:
766 ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1
769 The following example splits the channels of a stereo input into two separate
770 streams, which are put into the same output file:
772 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
775 Note that currently each output stream can only contain channels from a single
776 input stream; you can't for example use "-map_channel" to pick multiple input
777 audio channels contained in different streams (from the same or different files)
778 and merge them into a single output stream. It is therefore not currently
779 possible, for example, to turn two separate mono streams into a single stereo
780 stream. However splitting a stereo stream into two single channel mono streams
783 If you need this feature, a possible workaround is to use the @emph{amerge}
784 filter. For example, if you need to merge a media (here @file{input.mkv}) with 2
785 mono audio streams into one single stereo channel audio stream (and keep the
786 video stream), you can use the following command:
788 ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv
791 @item -map_metadata[:@var{metadata_spec_out}] @var{infile}[:@var{metadata_spec_in}] (@emph{output,per-metadata})
792 Set metadata information of the next output file from @var{infile}. Note that
793 those are file indices (zero-based), not filenames.
794 Optional @var{metadata_spec_in/out} parameters specify, which metadata to copy.
795 A metadata specifier can have the following forms:
798 global metadata, i.e. metadata that applies to the whole file
800 @item @var{s}[:@var{stream_spec}]
801 per-stream metadata. @var{stream_spec} is a stream specifier as described
802 in the @ref{Stream specifiers} chapter. In an input metadata specifier, the first
803 matching stream is copied from. In an output metadata specifier, all matching
804 streams are copied to.
806 @item @var{c}:@var{chapter_index}
807 per-chapter metadata. @var{chapter_index} is the zero-based chapter index.
809 @item @var{p}:@var{program_index}
810 per-program metadata. @var{program_index} is the zero-based program index.
812 If metadata specifier is omitted, it defaults to global.
814 By default, global metadata is copied from the first input file,
815 per-stream and per-chapter metadata is copied along with streams/chapters. These
816 default mappings are disabled by creating any mapping of the relevant type. A negative
817 file index can be used to create a dummy mapping that just disables automatic copying.
819 For example to copy metadata from the first stream of the input file to global metadata
822 ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3
825 To do the reverse, i.e. copy global metadata to all audio streams:
827 ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv
829 Note that simple @code{0} would work as well in this example, since global
830 metadata is assumed by default.
832 @item -map_chapters @var{input_file_index} (@emph{output})
833 Copy chapters from input file with index @var{input_file_index} to the next
834 output file. If no chapter mapping is specified, then chapters are copied from
835 the first input file with at least one chapter. Use a negative file index to
836 disable any chapter copying.
838 @item -benchmark (@emph{global})
839 Show benchmarking information at the end of an encode.
840 Shows CPU time used and maximum memory consumption.
841 Maximum memory consumption is not supported on all systems,
842 it will usually display as 0 if not supported.
843 @item -benchmark_all (@emph{global})
844 Show benchmarking information during the encode.
845 Shows CPU time used in various steps (audio/video encode/decode).
846 @item -timelimit @var{duration} (@emph{global})
847 Exit after ffmpeg has been running for @var{duration} seconds.
848 @item -dump (@emph{global})
849 Dump each input packet to stderr.
850 @item -hex (@emph{global})
851 When dumping packets, also dump the payload.
852 @item -re (@emph{input})
853 Read input at native frame rate. Mainly used to simulate a grab device.
854 By default @command{ffmpeg} attempts to read the input(s) as fast as possible.
855 This option will slow down the reading of the input(s) to the native frame rate
856 of the input(s). It is useful for real-time output (e.g. live streaming). If
857 your input(s) is coming from some other live streaming source (through HTTP or
858 UDP for example) the server might already be in real-time, thus the option will
859 likely not be required. On the other hand, this is meaningful if your input(s)
860 is a file you are trying to push in real-time.
862 Loop over the input stream. Currently it works only for image
863 streams. This option is used for automatic FFserver testing.
864 This option is deprecated, use -loop 1.
865 @item -loop_output @var{number_of_times}
866 Repeatedly loop output for formats that support looping such as animated GIF
867 (0 will loop the output infinitely).
868 This option is deprecated, use -loop.
869 @item -vsync @var{parameter}
871 For compatibility reasons old values can be specified as numbers.
872 Newly added values will have to be specified as strings always.
876 Each frame is passed with its timestamp from the demuxer to the muxer.
878 Frames will be duplicated and dropped to achieve exactly the requested
881 Frames are passed through with their timestamp or dropped so as to
882 prevent 2 frames from having the same timestamp.
884 As passthrough but destroys all timestamps, making the muxer generate
885 fresh timestamps based on frame-rate.
887 Chooses between 1 and 2 depending on muxer capabilities. This is the
891 With -map you can select from which stream the timestamps should be
892 taken. You can leave either video or audio unchanged and sync the
893 remaining stream(s) to the unchanged one.
895 @item -async @var{samples_per_second}
896 Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
897 the parameter is the maximum samples per second by which the audio is changed.
898 -async 1 is a special case where only the start of the audio stream is corrected
899 without any later correction.
900 This option has been deprecated. Use the @code{aresample} audio filter instead.
903 Do not process input timestamps, but keep their values without trying
904 to sanitize them. In particular, do not remove the initial start time
907 Note that, depending on the @option{vsync} option or on specific muxer
908 processing, the output timestamps may mismatch with the input
909 timestamps even when this option is selected.
911 @item -copytb @var{mode}
912 Specify how to set the encoder timebase when stream copying. @var{mode} is an
913 integer numeric value, and can assume one of the following values:
917 Use the demuxer timebase.
919 The time base is copied to the output encoder from the corresponding input
920 demuxer. This is sometimes required to avoid non monotonically increasing
921 timestamps when copying video streams with variable frame rate.
924 Use the decoder timebase.
926 The time base is copied to the output encoder from the corresponding input
930 Try to make the choice automatically, in order to generate a sane output.
935 @item -shortest (@emph{output})
936 Finish encoding when the shortest input stream ends.
937 @item -dts_delta_threshold
938 Timestamp discontinuity delta threshold.
939 @item -muxdelay @var{seconds} (@emph{input})
940 Set the maximum demux-decode delay.
941 @item -muxpreload @var{seconds} (@emph{input})
942 Set the initial demux-decode delay.
943 @item -streamid @var{output-stream-index}:@var{new-value} (@emph{output})
944 Assign a new stream-id value to an output stream. This option should be
945 specified prior to the output filename to which it applies.
946 For the situation where multiple output files exist, a streamid
947 may be reassigned to a different value.
949 For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for
950 an output mpegts file:
952 ffmpeg -i infile -streamid 0:33 -streamid 1:36 out.ts
955 @item -bsf[:@var{stream_specifier}] @var{bitstream_filters} (@emph{output,per-stream})
956 Set bitstream filters for matching streams. @var{bitstream_filters} is
957 a comma-separated list of bitstream filters. Use the @code{-bsfs} option
958 to get the list of bitstream filters.
960 ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264
963 ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt
966 @item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{per-stream})
967 Force a tag/fourcc for matching streams.
969 @item -timecode @var{hh}:@var{mm}:@var{ss}SEP@var{ff}
970 Specify Timecode for writing. @var{SEP} is ':' for non drop timecode and ';'
973 ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg
976 @anchor{filter_complex_option}
977 @item -filter_complex @var{filtergraph} (@emph{global})
978 Define a complex filter graph, i.e. one with arbitrary number of inputs and/or
979 outputs. For simple graphs -- those with one input and one output of the same
980 type -- see the @option{-filter} options. @var{filtergraph} is a description of
981 the filter graph, as described in the ``Filtergraph syntax'' section of the
982 ffmpeg-filters manual.
984 Input link labels must refer to input streams using the
985 @code{[file_index:stream_specifier]} syntax (i.e. the same as @option{-map}
986 uses). If @var{stream_specifier} matches multiple streams, the first one will be
987 used. An unlabeled input will be connected to the first unused input stream of
990 Output link labels are referred to with @option{-map}. Unlabeled outputs are
991 added to the first output file.
993 Note that with this option it is possible to use only lavfi sources without
996 For example, to overlay an image over video
998 ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
1001 Here @code{[0:v]} refers to the first video stream in the first input file,
1002 which is linked to the first (main) input of the overlay filter. Similarly the
1003 first video stream in the second input is linked to the second (overlay) input
1006 Assuming there is only one video stream in each input file, we can omit input
1007 labels, so the above is equivalent to
1009 ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map
1013 Furthermore we can omit the output label and the single output from the filter
1014 graph will be added to the output file automatically, so we can simply write
1016 ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv
1019 To generate 5 seconds of pure red video using lavfi @code{color} source:
1021 ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv
1025 As a special exception, you can use a bitmap subtitle stream as input: it
1026 will be converted into a video with the same size as the largest video in
1027 the file, or 720x576 if no video is present. Note that this is an
1028 experimental and temporary solution. It will be removed once libavfilter has
1029 proper support for subtitles.
1031 For example, to hardcode subtitles on top of a DVB-T recording stored in
1032 MPEG-TS format, delaying the subtitles by 1 second:
1034 ffmpeg -i input.ts -filter_complex \
1035 '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
1036 -sn -map '#0x2dc' output.mkv
1038 (0x2d0, 0x2dc and 0x2ef are the MPEG-TS PIDs of respectively the video,
1039 audio and subtitles streams; 0:0, 0:3 and 0:7 would have worked too)
1041 @section Preset files
1042 A preset file contains a sequence of @var{option}=@var{value} pairs,
1043 one for each line, specifying a sequence of options which would be
1044 awkward to specify on the command line. Lines starting with the hash
1045 ('#') character are ignored and are used to provide comments. Check
1046 the @file{presets} directory in the FFmpeg source tree for examples.
1048 Preset files are specified with the @code{vpre}, @code{apre},
1049 @code{spre}, and @code{fpre} options. The @code{fpre} option takes the
1050 filename of the preset instead of a preset name as input and can be
1051 used for any kind of codec. For the @code{vpre}, @code{apre}, and
1052 @code{spre} options, the options specified in a preset file are
1053 applied to the currently selected codec of the same type as the preset
1056 The argument passed to the @code{vpre}, @code{apre}, and @code{spre}
1057 preset options identifies the preset file to use according to the
1060 First ffmpeg searches for a file named @var{arg}.ffpreset in the
1061 directories @file{$FFMPEG_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
1062 the datadir defined at configuration time (usually @file{PREFIX/share/ffmpeg})
1063 or in a @file{ffpresets} folder along the executable on win32,
1064 in that order. For example, if the argument is @code{libvpx-1080p}, it will
1065 search for the file @file{libvpx-1080p.ffpreset}.
1067 If no such file is found, then ffmpeg will search for a file named
1068 @var{codec_name}-@var{arg}.ffpreset in the above-mentioned
1069 directories, where @var{codec_name} is the name of the codec to which
1070 the preset file options will be applied. For example, if you select
1071 the video codec with @code{-vcodec libvpx} and use @code{-vpre 1080p},
1072 then it will search for the file @file{libvpx-1080p.ffpreset}.
1080 For streaming at very low bitrate application, use a low frame rate
1081 and a small GOP size. This is especially true for RealVideo where
1082 the Linux player does not seem to be very fast, so it can miss
1083 frames. An example is:
1086 ffmpeg -g 3 -r 3 -t 10 -b:v 50k -s qcif -f rv10 /tmp/b.rm
1090 The parameter 'q' which is displayed while encoding is the current
1091 quantizer. The value 1 indicates that a very good quality could
1092 be achieved. The value 31 indicates the worst quality. If q=31 appears
1093 too often, it means that the encoder cannot compress enough to meet
1094 your bitrate. You must either increase the bitrate, decrease the
1095 frame rate or decrease the frame size.
1098 If your computer is not fast enough, you can speed up the
1099 compression at the expense of the compression ratio. You can use
1100 '-me zero' to speed up motion estimation, and '-g 0' to disable
1101 motion estimation completely (you have only I-frames, which means it
1102 is about as good as JPEG compression).
1105 To have very low audio bitrates, reduce the sampling frequency
1106 (down to 22050 Hz for MPEG audio, 22050 or 11025 for AC-3).
1109 To have a constant quality (but a variable bitrate), use the option
1110 '-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst
1117 @c man begin EXAMPLES
1119 @section Preset files
1121 A preset file contains a sequence of @var{option=value} pairs, one for
1122 each line, specifying a sequence of options which can be specified also on
1123 the command line. Lines starting with the hash ('#') character are ignored and
1124 are used to provide comments. Empty lines are also ignored. Check the
1125 @file{presets} directory in the FFmpeg source tree for examples.
1127 Preset files are specified with the @code{pre} option, this option takes a
1128 preset name as input. FFmpeg searches for a file named @var{preset_name}.avpreset in
1129 the directories @file{$AVCONV_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
1130 the data directory defined at configuration time (usually @file{$PREFIX/share/ffmpeg})
1131 in that order. For example, if the argument is @code{libx264-max}, it will
1132 search for the file @file{libx264-max.avpreset}.
1134 @section Video and Audio grabbing
1136 If you specify the input format and device then ffmpeg can grab video
1140 ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
1143 Or with an ALSA audio source (mono input, card id 1) instead of OSS:
1145 ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg
1148 Note that you must activate the right video source and channel before
1149 launching ffmpeg with any TV viewer such as
1150 @uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also
1151 have to set the audio recording levels correctly with a
1154 @section X11 grabbing
1156 Grab the X11 display with ffmpeg via
1159 ffmpeg -f x11grab -s cif -r 25 -i :0.0 /tmp/out.mpg
1162 0.0 is display.screen number of your X11 server, same as
1163 the DISPLAY environment variable.
1166 ffmpeg -f x11grab -s cif -r 25 -i :0.0+10,20 /tmp/out.mpg
1169 0.0 is display.screen number of your X11 server, same as the DISPLAY environment
1170 variable. 10 is the x-offset and 20 the y-offset for the grabbing.
1172 @section Video and Audio file format conversion
1174 Any supported file format and protocol can serve as input to ffmpeg:
1179 You can use YUV files as input:
1182 ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
1185 It will use the files:
1187 /tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
1188 /tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
1191 The Y files use twice the resolution of the U and V files. They are
1192 raw files, without header. They can be generated by all decent video
1193 decoders. You must specify the size of the image with the @option{-s} option
1194 if ffmpeg cannot guess it.
1197 You can input from a raw YUV420P file:
1200 ffmpeg -i /tmp/test.yuv /tmp/out.avi
1203 test.yuv is a file containing raw YUV planar data. Each frame is composed
1204 of the Y plane followed by the U and V planes at half vertical and
1205 horizontal resolution.
1208 You can output to a raw YUV420P file:
1211 ffmpeg -i mydivx.avi hugefile.yuv
1215 You can set several input files and output files:
1218 ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
1221 Converts the audio file a.wav and the raw YUV video file a.yuv
1225 You can also do audio and video conversions at the same time:
1228 ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
1231 Converts a.wav to MPEG audio at 22050 Hz sample rate.
1234 You can encode to several formats at the same time and define a
1235 mapping from input stream to output streams:
1238 ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2
1241 Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
1242 file:index' specifies which input stream is used for each output
1243 stream, in the order of the definition of output streams.
1246 You can transcode decrypted VOBs:
1249 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
1252 This is a typical DVD ripping example; the input is a VOB file, the
1253 output an AVI file with MPEG-4 video and MP3 audio. Note that in this
1254 command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
1255 GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
1256 input video. Furthermore, the audio stream is MP3-encoded so you need
1257 to enable LAME support by passing @code{--enable-libmp3lame} to configure.
1258 The mapping is particularly useful for DVD transcoding
1259 to get the desired audio language.
1261 NOTE: To see the supported input formats, use @code{ffmpeg -formats}.
1264 You can extract images from a video, or create a video from many images:
1266 For extracting images from a video:
1268 ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
1271 This will extract one video frame per second from the video and will
1272 output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg},
1273 etc. Images will be rescaled to fit the new WxH values.
1275 If you want to extract just a limited number of frames, you can use the
1276 above command in combination with the -vframes or -t option, or in
1277 combination with -ss to start extracting from a certain point in time.
1279 For creating a video from many images:
1281 ffmpeg -f image2 -i foo-%03d.jpeg -r 12 -s WxH foo.avi
1284 The syntax @code{foo-%03d.jpeg} specifies to use a decimal number
1285 composed of three digits padded with zeroes to express the sequence
1286 number. It is the same syntax supported by the C printf function, but
1287 only formats accepting a normal integer are suitable.
1289 When importing an image sequence, -i also supports expanding
1290 shell-like wildcard patterns (globbing) internally, by selecting the
1291 image2-specific @code{-pattern_type glob} option.
1293 For example, for creating a video from filenames matching the glob pattern
1296 ffmpeg -f image2 -pattern_type glob -i 'foo-*.jpeg' -r 12 -s WxH foo.avi
1300 You can put many streams of the same type in the output:
1303 ffmpeg -i test1.avi -i test2.avi -map 0:3 -map 0:2 -map 0:1 -map 0:0 -c copy test12.nut
1306 The resulting output file @file{test12.avi} will contain first four streams from
1307 the input file in reverse order.
1310 To force CBR video output:
1312 ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
1316 The four options lmin, lmax, mblmin and mblmax use 'lambda' units,
1317 but you may use the QP2LAMBDA constant to easily convert from 'q' units:
1319 ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
1328 @url{ffplay.html,ffplay}, @url{ffprobe.html,ffprobe}, @url{ffserver.html,ffserver},
1329 @url{ffmpeg-utils.html,ffmpeg-utils},
1330 @url{ffmpeg-scaler.html,ffmpeg-scaler},
1331 @url{ffmpeg-resampler.html,ffmpeg-resampler},
1332 @url{ffmpeg-codecs.html,ffmpeg-codecs},
1333 @url{ffmpeg-bitstream-filters.html,ffmpeg-bitstream-filters},
1334 @url{ffmpeg-formats.html,ffmpeg-formats},
1335 @url{ffmpeg-devices.html,ffmpeg-devices},
1336 @url{ffmpeg-protocols.html,ffmpeg-protocols},
1337 @url{ffmpeg-filters.html,ffmpeg-filters}
1341 ffplay(1), ffprobe(1), ffserver(1),
1342 ffmpeg-utils(1), ffmpeg-scaler(1), ffmpeg-resampler(1),
1343 ffmpeg-codecs(1), ffmpeg-bitstream-filters(1), ffmpeg-formats(1),
1344 ffmpeg-devices(1), ffmpeg-protocols(1), ffmpeg-filters(1)
1347 @include authors.texi
1352 @settitle ffmpeg video converter