1 \input texinfo @c -*- texinfo -*-
3 @settitle ffmpeg Documentation
5 @center @titlefont{ffmpeg Documentation}
14 The generic syntax is:
18 ffmpeg [global options] [[infile options][@option{-i} @var{infile}]]... @{[outfile options] @var{outfile}@}...
23 @c man begin DESCRIPTION
25 ffmpeg is a very fast video and audio converter that can also grab from
26 a live audio/video source. It can also convert between arbitrary sample
27 rates and resize video on the fly with a high quality polyphase filter.
29 ffmpeg reads from an arbitrary number of input "files" (which can be regular
30 files, pipes, network streams, grabbing devices, etc.), specified by the
31 @code{-i} option, and writes to an arbitrary number of output "files", which are
32 specified by a plain output filename. Anything found on the command line which
33 cannot be interpreted as an option is considered to be an output filename.
35 Each input or output file can in principle contain any number of streams of
36 different types (video/audio/subtitle/attachment/data). Allowed number and/or
37 types of streams can be limited by the container format. Selecting, which
38 streams from which inputs go into output, is done either automatically or with
39 the @code{-map} option (see the Stream selection chapter).
41 To refer to input files in options, you must use their indices (0-based). E.g.
42 the first input file is @code{0}, the second is @code{1} etc. Similarly, streams
43 within a file are referred to by their indices. E.g. @code{2:3} refers to the
44 fourth stream in the third input file. See also the Stream specifiers chapter.
46 As a general rule, options are applied to the next specified
47 file. Therefore, order is important, and you can have the same
48 option on the command line multiple times. Each occurrence is
49 then applied to the next input or output file.
50 Exceptions from this rule are the global options (e.g. verbosity level),
51 which should be specified first.
53 Do not mix input and output files -- first specify all input files, then all
54 output files. Also do not mix options which belong to different files. All
55 options apply ONLY to the next input or output file and are reset between files.
59 To set the video bitrate of the output file to 64kbit/s:
61 ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi
65 To force the frame rate of the output file to 24 fps:
67 ffmpeg -i input.avi -r 24 output.avi
71 To force the frame rate of the input file (valid for raw formats only)
72 to 1 fps and the frame rate of the output file to 24 fps:
74 ffmpeg -r 1 -i input.m2v -r 24 output.avi
78 The format option may be needed for raw input files.
80 @c man end DESCRIPTION
82 @chapter Detailed description
83 @c man begin DETAILED DESCRIPTION
85 The transcoding process in @command{ffmpeg} for each output can be described by
86 the following diagram:
89 _______ ______________ _________ ______________ ________
91 | input | demuxer | encoded data | decoder | decoded | encoder | encoded data | muxer | output |
92 | file | ---------> | packets | ---------> | frames | ---------> | packets | -------> | file |
93 |_______| |______________| |_________| |______________| |________|
97 @command{ffmpeg} calls the libavformat library (containing demuxers) to read
98 input files and get packets containing encoded data from them. When there are
99 multiple input files, @command{ffmpeg} tries to keep them synchronized by
100 tracking lowest timestamp on any active input stream.
102 Encoded packets are then passed to the decoder (unless streamcopy is selected
103 for the stream, see further for a description). The decoder produces
104 uncompressed frames (raw video/PCM audio/...) which can be processed further by
105 filtering (see next section). After filtering the frames are passed to the
106 encoder, which encodes them and outputs encoded packets again. Finally those are
107 passed to the muxer, which writes the encoded packets to the output file.
110 Before encoding, @command{ffmpeg} can process raw audio and video frames using
111 filters from the libavfilter library. Several chained filters form a filter
112 graph. @command{ffmpeg} distinguishes between two types of filtergraphs -
115 @subsection Simple filtergraphs
116 Simple filtergraphs are those that have exactly one input and output, both of
117 the same type. In the above diagram they can be represented by simply inserting
118 an additional step between decoding and encoding:
121 _________ __________ ______________
123 | decoded | simple filtergraph | filtered | encoder | encoded data |
124 | frames | -------------------> | frames | ---------> | packets |
125 |_________| |__________| |______________|
129 Simple filtergraphs are configured with the per-stream @option{-filter} option
130 (with @option{-vf} and @option{-af} aliases for video and audio respectively).
131 A simple filtergraph for video can look for example like this:
134 _______ _____________ _______ _____ ________
136 | input | ---> | deinterlace | ---> | scale | ---> | fps | ---> | output |
137 |_______| |_____________| |_______| |_____| |________|
141 Note that some filters change frame properties but not frame contents. E.g. the
142 @code{fps} filter in the example above changes number of frames, but does not
143 touch the frame contents. Another example is the @code{setpts} filter, which
144 only sets timestamps and otherwise passes the frames unchanged.
146 @subsection Complex filtergraphs
147 Complex filtergraphs are those which cannot be described as simply a linear
148 processing chain applied to one stream. This is the case e.g. when the graph has
149 more than one input and/or output, or when output stream type is different from
150 input. They can be represented with the following diagram:
155 | input 0 |\ __________
157 \ _________ /| output 0 |
159 _________ \| complex | /
161 | input 1 |---->| filter |\
162 |_________| | | \ __________
165 _________ / |_________| |__________|
172 Complex filtergraphs are configured with the @option{-filter_complex} option.
173 Note that this option is global, since a complex filtergraph by its nature
174 cannot be unambiguously associated with a single stream or file.
176 A trivial example of a complex filtergraph is the @code{overlay} filter, which
177 has two video inputs and one video output, containing one video overlaid on top
178 of the other. Its audio counterpart is the @code{amix} filter.
181 Stream copy is a mode selected by supplying the @code{copy} parameter to the
182 @option{-codec} option. It makes @command{ffmpeg} omit the decoding and encoding
183 step for the specified stream, so it does only demuxing and muxing. It is useful
184 for changing the container format or modifying container-level metadata. The
185 diagram above will in this case simplify to this:
188 _______ ______________ ________
190 | input | demuxer | encoded data | muxer | output |
191 | file | ---------> | packets | -------> | file |
192 |_______| |______________| |________|
196 Since there is no decoding or encoding, it is very fast and there is no quality
197 loss. However it might not work in some cases because of many factors. Applying
198 filters is obviously also impossible, since filters work on uncompressed data.
200 @c man end DETAILED DESCRIPTION
202 @chapter Stream selection
203 @c man begin STREAM SELECTION
205 By default ffmpeg includes only one stream of each type (video, audio, subtitle)
206 present in the input files and adds them to each output file. It picks the
207 "best" of each based upon the following criteria; for video it is the stream
208 with the highest resolution, for audio the stream with the most channels, for
209 subtitle it's the first subtitle stream. In the case where several streams of
210 the same type rate equally, the lowest numbered stream is chosen.
212 You can disable some of those defaults by using @code{-vn/-an/-sn} options. For
213 full manual control, use the @code{-map} option, which disables the defaults just
216 @c man end STREAM SELECTION
221 @include avtools-common-opts.texi
223 @section Main options
227 @item -f @var{fmt} (@emph{input/output})
228 Force input or output file format. The format is normally auto detected for input
229 files and guessed from file extension for output files, so this option is not
230 needed in most cases.
232 @item -i @var{filename} (@emph{input})
235 @item -y (@emph{global})
236 Overwrite output files without asking.
238 @item -n (@emph{global})
239 Do not overwrite output files but exit if file exists.
241 @item -c[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
242 @itemx -codec[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
243 Select an encoder (when used before an output file) or a decoder (when used
244 before an input file) for one or more streams. @var{codec} is the name of a
245 decoder/encoder or a special value @code{copy} (output only) to indicate that
246 the stream is not to be re-encoded.
250 ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT
252 encodes all video streams with libx264 and copies all audio streams.
254 For each stream, the last matching @code{c} option is applied, so
256 ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT
258 will copy all the streams except the second video, which will be encoded with
259 libx264, and the 138th audio, which will be encoded with libvorbis.
261 @item -t @var{duration} (@emph{output})
262 Stop writing the output after its duration reaches @var{duration}.
263 @var{duration} may be a number in seconds, or in @code{hh:mm:ss[.xxx]} form.
265 @item -fs @var{limit_size} (@emph{output})
266 Set the file size limit, expressed in bytes.
268 @item -ss @var{position} (@emph{input/output})
269 When used as an input option (before @code{-i}), seeks in this input file to
270 @var{position}. When used as an output option (before an output filename),
271 decodes but discards input until the timestamps reach @var{position}. This is
272 slower, but more accurate.
274 @var{position} may be either in seconds or in @code{hh:mm:ss[.xxx]} form.
276 @item -itsoffset @var{offset} (@emph{input})
277 Set the input time offset in seconds.
278 @code{[-]hh:mm:ss[.xxx]} syntax is also supported.
279 The offset is added to the timestamps of the input files.
280 Specifying a positive offset means that the corresponding
281 streams are delayed by @var{offset} seconds.
283 @item -timestamp @var{time} (@emph{output})
284 Set the recording timestamp in the container.
285 The syntax for @var{time} is:
287 now|([(YYYY-MM-DD|YYYYMMDD)[T|t| ]]((HH:MM:SS[.m...])|(HHMMSS[.m...]))[Z|z])
289 If the value is "now" it takes the current time.
290 Time is local time unless 'Z' or 'z' is appended, in which case it is
292 If the year-month-day part is not specified it takes the current
295 @item -metadata[:metadata_specifier] @var{key}=@var{value} (@emph{output,per-metadata})
296 Set a metadata key/value pair.
298 An optional @var{metadata_specifier} may be given to set metadata
299 on streams or chapters. See @code{-map_metadata} documentation for
302 This option overrides metadata set with @code{-map_metadata}. It is
303 also possible to delete metadata by using an empty value.
305 For example, for setting the title in the output file:
307 ffmpeg -i in.avi -metadata title="my title" out.flv
310 To set the language of the first audio stream:
312 ffmpeg -i INPUT -metadata:s:a:1 language=eng OUTPUT
315 @item -target @var{type} (@emph{output})
316 Specify target file type (@code{vcd}, @code{svcd}, @code{dvd}, @code{dv},
317 @code{dv50}). @var{type} may be prefixed with @code{pal-}, @code{ntsc-} or
318 @code{film-} to use the corresponding standard. All the format options
319 (bitrate, codecs, buffer sizes) are then set automatically. You can just type:
322 ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
325 Nevertheless you can specify additional options as long as you know
326 they do not conflict with the standard, as in:
329 ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
332 @item -dframes @var{number} (@emph{output})
333 Set the number of data frames to record. This is an alias for @code{-frames:d}.
335 @item -frames[:@var{stream_specifier}] @var{framecount} (@emph{output,per-stream})
336 Stop writing to the stream after @var{framecount} frames.
338 @item -q[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
339 @itemx -qscale[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
340 Use fixed quality scale (VBR). The meaning of @var{q} is
343 @item -filter[:@var{stream_specifier}] @var{filter_graph} (@emph{output,per-stream})
344 @var{filter_graph} is a description of the filter graph to apply to
345 the stream. Use @code{-filters} to show all the available filters
346 (including also sources and sinks).
348 See also the @option{-filter_complex} option if you want to create filter graphs
349 with multiple inputs and/or outputs.
350 @item -pre[:@var{stream_specifier}] @var{preset_name} (@emph{output,per-stream})
351 Specify the preset for matching stream(s).
353 @item -stats (@emph{global})
354 Print encoding progress/statistics. On by default.
356 @item -progress @var{url} (@emph{global})
357 Send program-friendly progress information to @var{url}.
359 Progress information is written approximately every second and at the end of
360 the encoding process. It is made of "@var{key}=@var{value}" lines. @var{key}
361 consists of only alphanumeric characters. The last key of a sequence of
362 progress information is always "progress".
365 Enable interaction on standard input. On by default unless standard input is
366 used as an input. To explicitly disable interaction you need to specify
369 Disabling interaction on standard input is useful, for example, if
370 ffmpeg is in the background process group. Roughly the same result can
371 be achieved with @code{ffmpeg ... < /dev/null} but it requires a
374 @item -debug_ts (@emph{global})
375 Print timestamp information. It is off by default. This option is
376 mostly useful for testing and debugging purposes, and the output
377 format may change from one version to another, so it should not be
378 employed by portable scripts.
380 See also the option @code{-fdebug ts}.
382 @item -attach @var{filename} (@emph{output})
383 Add an attachment to the output file. This is supported by a few formats
384 like Matroska for e.g. fonts used in rendering subtitles. Attachments
385 are implemented as a specific type of stream, so this option will add
386 a new stream to the file. It is then possible to use per-stream options
387 on this stream in the usual way. Attachment streams created with this
388 option will be created after all the other streams (i.e. those created
389 with @code{-map} or automatic mappings).
391 Note that for Matroska you also have to set the mimetype metadata tag:
393 ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv
395 (assuming that the attachment stream will be third in the output file).
397 @item -dump_attachment[:@var{stream_specifier}] @var{filename} (@emph{input,per-stream})
398 Extract the matching attachment stream into a file named @var{filename}. If
399 @var{filename} is empty, then the value of the @code{filename} metadata tag
402 E.g. to extract the first attachment to a file named 'out.ttf':
404 ffmpeg -dump_attachment:t:0 out.ttf INPUT
406 To extract all attachments to files determined by the @code{filename} tag:
408 ffmpeg -dump_attachment:t "" INPUT
411 Technical note -- attachments are implemented as codec extradata, so this
412 option can actually be used to extract extradata from any stream, not just
417 @section Video Options
420 @item -vframes @var{number} (@emph{output})
421 Set the number of video frames to record. This is an alias for @code{-frames:v}.
422 @item -r[:@var{stream_specifier}] @var{fps} (@emph{input/output,per-stream})
423 Set frame rate (Hz value, fraction or abbreviation).
425 As an input option, ignore any timestamps stored in the file and instead
426 generate timestamps assuming constant frame rate @var{fps}.
428 As an output option, duplicate or drop input frames to achieve constant output
429 frame rate @var{fps} (note that this actually causes the @code{fps} filter to be
430 inserted to the end of the corresponding filtergraph).
432 @item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream})
435 As an input option, this is a shortcut for the @option{video_size} private
436 option, recognized by some demuxers for which the frame size is either not
437 stored in the file or is configurable -- e.g. raw video or video grabbers.
439 As an output option, this inserts the @code{scale} video filter to the
440 @emph{end} of the corresponding filtergraph. Please use the @code{scale} filter
441 directly to insert it at the beginning or some other place.
443 The format is @samp{wxh} (default - same as source).
445 @item -aspect[:@var{stream_specifier}] @var{aspect} (@emph{output,per-stream})
446 Set the video display aspect ratio specified by @var{aspect}.
448 @var{aspect} can be a floating point number string, or a string of the
449 form @var{num}:@var{den}, where @var{num} and @var{den} are the
450 numerator and denominator of the aspect ratio. For example "4:3",
451 "16:9", "1.3333", and "1.7777" are valid argument values.
453 @item -croptop @var{size}
454 @item -cropbottom @var{size}
455 @item -cropleft @var{size}
456 @item -cropright @var{size}
457 All the crop options have been removed. Use -vf
458 crop=width:height:x:y instead.
460 @item -padtop @var{size}
461 @item -padbottom @var{size}
462 @item -padleft @var{size}
463 @item -padright @var{size}
464 @item -padcolor @var{hex_color}
465 All the pad options have been removed. Use -vf
466 pad=width:height:x:y:color instead.
468 @item -vn (@emph{output})
469 Disable video recording.
471 @item -vcodec @var{codec} (@emph{output})
472 Set the video codec. This is an alias for @code{-codec:v}.
474 @item -pass[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
475 Select the pass number (1 or 2). It is used to do two-pass
476 video encoding. The statistics of the video are recorded in the first
477 pass into a log file (see also the option -passlogfile),
478 and in the second pass that log file is used to generate the video
479 at the exact requested bitrate.
480 On pass 1, you may just deactivate audio and set output to null,
481 examples for Windows and Unix:
483 ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
484 ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null
487 @item -passlogfile[:@var{stream_specifier}] @var{prefix} (@emph{output,per-stream})
488 Set two-pass log file name prefix to @var{prefix}, the default file name
489 prefix is ``ffmpeg2pass''. The complete file name will be
490 @file{PREFIX-N.log}, where N is a number specific to the output
493 @item -vlang @var{code}
494 Set the ISO 639 language code (3 letters) of the current video stream.
496 @item -vf @var{filter_graph} (@emph{output})
497 @var{filter_graph} is a description of the filter graph to apply to
499 Use the option "-filters" to show all the available filters (including
500 also sources and sinks). This is an alias for @code{-filter:v}.
504 @section Advanced Video Options
507 @item -pix_fmt[:@var{stream_specifier}] @var{format} (@emph{input/output,per-stream})
508 Set pixel format. Use @code{-pix_fmts} to show all the supported
510 If the selected pixel format can not be selected, ffmpeg will print a
511 warning and select the best pixel format supported by the encoder.
512 If @var{pix_fmt} is prefixed by a @code{+}, ffmpeg will exit with an error
513 if the requested pixel format can not be selected, and automatic conversions
514 inside filter graphs are disabled.
515 If @var{pix_fmt} is a single @code{+}, ffmpeg selects the same pixel format
516 as the input (or graph output) and automatic conversions are disabled.
518 @item -sws_flags @var{flags} (@emph{input/output})
523 @item -rc_override[:@var{stream_specifier}] @var{override} (@emph{output,per-stream})
524 Rate control override for specific intervals, formatted as "int,int,int"
525 list separated with slashes. Two first values are the beginning and
526 end frame numbers, last one is quantizer to use if positive, or quality
530 Deinterlace pictures.
531 This option is deprecated since the deinterlacing is very low quality.
532 Use the yadif filter with @code{-filter:v yadif}.
534 Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
535 Use this option if your input file is interlaced and you want
536 to keep the interlaced format for minimum losses.
537 The alternative is to deinterlace the input stream with
538 @option{-deinterlace}, but deinterlacing introduces losses.
540 Calculate PSNR of compressed frames.
542 Dump video coding statistics to @file{vstats_HHMMSS.log}.
543 @item -vstats_file @var{file}
544 Dump video coding statistics to @var{file}.
545 @item -top[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
546 top=1/bottom=0/auto=-1 field first
547 @item -dc @var{precision}
549 @item -vtag @var{fourcc/tag} (@emph{output})
550 Force video tag/fourcc. This is an alias for @code{-tag:v}.
551 @item -qphist (@emph{global})
553 @item -vbsf @var{bitstream_filter}
555 @item -force_key_frames[:@var{stream_specifier}] @var{time}[,@var{time}...] (@emph{output,per-stream})
556 Force key frames at the specified timestamps, more precisely at the first
557 frames after each specified time.
558 This option can be useful to ensure that a seek point is present at a
559 chapter mark or any other designated place in the output file.
560 The timestamps must be specified in ascending order.
562 @item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream})
563 When doing stream copy, copy also non-key frames found at the
567 @section Audio Options
570 @item -aframes @var{number} (@emph{output})
571 Set the number of audio frames to record. This is an alias for @code{-frames:a}.
572 @item -ar[:@var{stream_specifier}] @var{freq} (@emph{input/output,per-stream})
573 Set the audio sampling frequency. For output streams it is set by
574 default to the frequency of the corresponding input stream. For input
575 streams this option only makes sense for audio grabbing devices and raw
576 demuxers and is mapped to the corresponding demuxer options.
577 @item -aq @var{q} (@emph{output})
578 Set the audio quality (codec-specific, VBR). This is an alias for -q:a.
579 @item -ac[:@var{stream_specifier}] @var{channels} (@emph{input/output,per-stream})
580 Set the number of audio channels. For output streams it is set by
581 default to the number of input audio channels. For input streams
582 this option only makes sense for audio grabbing devices and raw demuxers
583 and is mapped to the corresponding demuxer options.
584 @item -an (@emph{output})
585 Disable audio recording.
586 @item -acodec @var{codec} (@emph{input/output})
587 Set the audio codec. This is an alias for @code{-codec:a}.
588 @item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream})
589 Set the audio sample format. Use @code{-sample_fmts} to get a list
590 of supported sample formats.
591 @item -af @var{filter_graph} (@emph{output})
592 @var{filter_graph} is a description of the filter graph to apply to
594 Use the option "-filters" to show all the available filters (including
595 also sources and sinks). This is an alias for @code{-filter:a}.
598 @section Advanced Audio options:
601 @item -atag @var{fourcc/tag} (@emph{output})
602 Force audio tag/fourcc. This is an alias for @code{-tag:a}.
603 @item -absf @var{bitstream_filter}
607 @section Subtitle options:
610 @item -slang @var{code}
611 Set the ISO 639 language code (3 letters) of the current subtitle stream.
612 @item -scodec @var{codec} (@emph{input/output})
613 Set the subtitle codec. This is an alias for @code{-codec:s}.
614 @item -sn (@emph{output})
615 Disable subtitle recording.
616 @item -sbsf @var{bitstream_filter}
620 @section Advanced Subtitle options:
624 @item -fix_sub_duration
625 Fix subtitles durations. For each subtitle, wait for the next packet in the
626 same stream and adjust the duration of the first to avoid overlap. This is
627 necessary with some subtitles codecs, especially DVB subtitles, because the
628 duration in the original packet is only a rough estimate and the end is
629 actually marked by an empty subtitle frame. Failing to use this option when
630 necessary can result in exaggerated durations or muxing failures due to
631 non-monotonic timestamps.
633 Note that this option will delay the output of all data until the next
634 subtitle packet is decoded: it may increase memory consumption and latency a
639 @section Advanced options
642 @item -map [-]@var{input_file_id}[:@var{stream_specifier}][,@var{sync_file_id}[:@var{stream_specifier}]] | @var{[linklabel]} (@emph{output})
644 Designate one or more input streams as a source for the output file. Each input
645 stream is identified by the input file index @var{input_file_id} and
646 the input stream index @var{input_stream_id} within the input
647 file. Both indices start at 0. If specified,
648 @var{sync_file_id}:@var{stream_specifier} sets which input stream
649 is used as a presentation sync reference.
651 The first @code{-map} option on the command line specifies the
652 source for output stream 0, the second @code{-map} option specifies
653 the source for output stream 1, etc.
655 A @code{-} character before the stream identifier creates a "negative" mapping.
656 It disables matching streams from already created mappings.
658 An alternative @var{[linklabel]} form will map outputs from complex filter
659 graphs (see the @option{-filter_complex} option) to the output file.
660 @var{linklabel} must correspond to a defined output link label in the graph.
662 For example, to map ALL streams from the first input file to output
664 ffmpeg -i INPUT -map 0 output
667 For example, if you have two audio streams in the first input file,
668 these streams are identified by "0:0" and "0:1". You can use
669 @code{-map} to select which streams to place in an output file. For
672 ffmpeg -i INPUT -map 0:1 out.wav
674 will map the input stream in @file{INPUT} identified by "0:1" to
675 the (single) output stream in @file{out.wav}.
677 For example, to select the stream with index 2 from input file
678 @file{a.mov} (specified by the identifier "0:2"), and stream with
679 index 6 from input @file{b.mov} (specified by the identifier "1:6"),
680 and copy them to the output file @file{out.mov}:
682 ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
685 To select all video and the third audio stream from an input file:
687 ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT
690 To map all the streams except the second audio, use negative mappings
692 ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT
695 Note that using this option disables the default mappings for this output file.
697 @item -map_channel [@var{input_file_id}.@var{stream_specifier}.@var{channel_id}|-1][:@var{output_file_id}.@var{stream_specifier}]
698 Map an audio channel from a given input to an output. If
699 @var{output_file_id}.@var{stream_specifier} is not set, the audio channel will
700 be mapped on all the audio streams.
702 Using "-1" instead of
703 @var{input_file_id}.@var{stream_specifier}.@var{channel_id} will map a muted
706 For example, assuming @var{INPUT} is a stereo audio file, you can switch the
707 two audio channels with the following command:
709 ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT
712 If you want to mute the first channel and keep the second:
714 ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT
717 The order of the "-map_channel" option specifies the order of the channels in
718 the output stream. The output channel layout is guessed from the number of
719 channels mapped (mono if one "-map_channel", stereo if two, etc.). Using "-ac"
720 in combination of "-map_channel" makes the channel gain levels to be updated if
721 input and output channel layouts don't match (for instance two "-map_channel"
722 options and "-ac 6").
724 You can also extract each channel of an input to specific outputs; the following
725 command extracts two channels of the @var{INPUT} audio stream (file 0, stream 0)
726 to the respective @var{OUTPUT_CH0} and @var{OUTPUT_CH1} outputs:
728 ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1
731 The following example splits the channels of a stereo input into two separate
732 streams, which are put into the same output file:
734 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
737 Note that currently each output stream can only contain channels from a single
738 input stream; you can't for example use "-map_channel" to pick multiple input
739 audio channels contained in different streams (from the same or different files)
740 and merge them into a single output stream. It is therefore not currently
741 possible, for example, to turn two separate mono streams into a single stereo
742 stream. However splitting a stereo stream into two single channel mono streams
745 If you need this feature, a possible workaround is to use the @emph{amerge}
746 filter. For example, if you need to merge a media (here @file{input.mkv}) with 2
747 mono audio streams into one single stereo channel audio stream (and keep the
748 video stream), you can use the following command:
750 ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv
753 @item -map_metadata[:@var{metadata_spec_out}] @var{infile}[:@var{metadata_spec_in}] (@emph{output,per-metadata})
754 Set metadata information of the next output file from @var{infile}. Note that
755 those are file indices (zero-based), not filenames.
756 Optional @var{metadata_spec_in/out} parameters specify, which metadata to copy.
757 A metadata specifier can have the following forms:
760 global metadata, i.e. metadata that applies to the whole file
762 @item @var{s}[:@var{stream_spec}]
763 per-stream metadata. @var{stream_spec} is a stream specifier as described
764 in the @ref{Stream specifiers} chapter. In an input metadata specifier, the first
765 matching stream is copied from. In an output metadata specifier, all matching
766 streams are copied to.
768 @item @var{c}:@var{chapter_index}
769 per-chapter metadata. @var{chapter_index} is the zero-based chapter index.
771 @item @var{p}:@var{program_index}
772 per-program metadata. @var{program_index} is the zero-based program index.
774 If metadata specifier is omitted, it defaults to global.
776 By default, global metadata is copied from the first input file,
777 per-stream and per-chapter metadata is copied along with streams/chapters. These
778 default mappings are disabled by creating any mapping of the relevant type. A negative
779 file index can be used to create a dummy mapping that just disables automatic copying.
781 For example to copy metadata from the first stream of the input file to global metadata
784 ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3
787 To do the reverse, i.e. copy global metadata to all audio streams:
789 ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv
791 Note that simple @code{0} would work as well in this example, since global
792 metadata is assumed by default.
794 @item -map_chapters @var{input_file_index} (@emph{output})
795 Copy chapters from input file with index @var{input_file_index} to the next
796 output file. If no chapter mapping is specified, then chapters are copied from
797 the first input file with at least one chapter. Use a negative file index to
798 disable any chapter copying.
800 @item -benchmark (@emph{global})
801 Show benchmarking information at the end of an encode.
802 Shows CPU time used and maximum memory consumption.
803 Maximum memory consumption is not supported on all systems,
804 it will usually display as 0 if not supported.
805 @item -benchmark_all (@emph{global})
806 Show benchmarking information during the encode.
807 Shows CPU time used in various steps (audio/video encode/decode).
808 @item -timelimit @var{duration} (@emph{global})
809 Exit after ffmpeg has been running for @var{duration} seconds.
810 @item -dump (@emph{global})
811 Dump each input packet to stderr.
812 @item -hex (@emph{global})
813 When dumping packets, also dump the payload.
814 @item -re (@emph{input})
815 Read input at native frame rate. Mainly used to simulate a grab device.
816 By default @command{ffmpeg} attempts to read the input(s) as fast as possible.
817 This option will slow down the reading of the input(s) to the native frame rate
818 of the input(s). It is useful for real-time output (e.g. live streaming). If
819 your input(s) is coming from some other live streaming source (through HTTP or
820 UDP for example) the server might already be in real-time, thus the option will
821 likely not be required. On the other hand, this is meaningful if your input(s)
822 is a file you are trying to push in real-time.
824 Loop over the input stream. Currently it works only for image
825 streams. This option is used for automatic FFserver testing.
826 This option is deprecated, use -loop 1.
827 @item -loop_output @var{number_of_times}
828 Repeatedly loop output for formats that support looping such as animated GIF
829 (0 will loop the output infinitely).
830 This option is deprecated, use -loop.
831 @item -vsync @var{parameter}
833 For compatibility reasons old values can be specified as numbers.
834 Newly added values will have to be specified as strings always.
838 Each frame is passed with its timestamp from the demuxer to the muxer.
840 Frames will be duplicated and dropped to achieve exactly the requested
843 Frames are passed through with their timestamp or dropped so as to
844 prevent 2 frames from having the same timestamp.
846 As passthrough but destroys all timestamps, making the muxer generate
847 fresh timestamps based on frame-rate.
849 Chooses between 1 and 2 depending on muxer capabilities. This is the
853 With -map you can select from which stream the timestamps should be
854 taken. You can leave either video or audio unchanged and sync the
855 remaining stream(s) to the unchanged one.
857 @item -async @var{samples_per_second}
858 Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
859 the parameter is the maximum samples per second by which the audio is changed.
860 -async 1 is a special case where only the start of the audio stream is corrected
861 without any later correction.
862 This option has been deprecated. Use the @code{asyncts} audio filter instead.
864 Copy timestamps from input to output.
865 @item -copytb @var{mode}
866 Specify how to set the encoder timebase when stream copying. @var{mode} is an
867 integer numeric value, and can assume one of the following values:
871 Use the demuxer timebase.
873 The time base is copied to the output encoder from the corresponding input
874 demuxer. This is sometimes required to avoid non monotonically increasing
875 timestamps when copying video streams with variable frame rate.
878 Use the decoder timebase.
880 The time base is copied to the output encoder from the corresponding input
884 Try to make the choice automatically, in order to generate a sane output.
889 @item -shortest (@emph{output})
890 Finish encoding when the shortest input stream ends.
891 @item -dts_delta_threshold
892 Timestamp discontinuity delta threshold.
893 @item -muxdelay @var{seconds} (@emph{input})
894 Set the maximum demux-decode delay.
895 @item -muxpreload @var{seconds} (@emph{input})
896 Set the initial demux-decode delay.
897 @item -streamid @var{output-stream-index}:@var{new-value} (@emph{output})
898 Assign a new stream-id value to an output stream. This option should be
899 specified prior to the output filename to which it applies.
900 For the situation where multiple output files exist, a streamid
901 may be reassigned to a different value.
903 For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for
904 an output mpegts file:
906 ffmpeg -i infile -streamid 0:33 -streamid 1:36 out.ts
909 @item -bsf[:@var{stream_specifier}] @var{bitstream_filters} (@emph{output,per-stream})
910 Set bitstream filters for matching streams. @var{bistream_filters} is
911 a comma-separated list of bitstream filters. Use the @code{-bsfs} option
912 to get the list of bitstream filters.
914 ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264
917 ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt
920 @item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{per-stream})
921 Force a tag/fourcc for matching streams.
923 @item -timecode @var{hh}:@var{mm}:@var{ss}SEP@var{ff}
924 Specify Timecode for writing. @var{SEP} is ':' for non drop timecode and ';'
927 ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg
930 @item -filter_complex @var{filtergraph} (@emph{global})
931 Define a complex filter graph, i.e. one with arbitrary number of inputs and/or
932 outputs. For simple graphs -- those with one input and one output of the same
933 type -- see the @option{-filter} options. @var{filtergraph} is a description of
934 the filter graph, as described in @ref{Filtergraph syntax}.
936 Input link labels must refer to input streams using the
937 @code{[file_index:stream_specifier]} syntax (i.e. the same as @option{-map}
938 uses). If @var{stream_specifier} matches multiple streams, the first one will be
939 used. An unlabeled input will be connected to the first unused input stream of
942 Output link labels are referred to with @option{-map}. Unlabeled outputs are
943 added to the first output file.
945 Note that with this option it is possible to use only lavfi sources without
948 For example, to overlay an image over video
950 ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
953 Here @code{[0:v]} refers to the first video stream in the first input file,
954 which is linked to the first (main) input of the overlay filter. Similarly the
955 first video stream in the second input is linked to the second (overlay) input
958 Assuming there is only one video stream in each input file, we can omit input
959 labels, so the above is equivalent to
961 ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map
965 Furthermore we can omit the output label and the single output from the filter
966 graph will be added to the output file automatically, so we can simply write
968 ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv
971 To generate 5 seconds of pure red video using lavfi @code{color} source:
973 ffmpeg -filter_complex 'color=red' -t 5 out.mkv
977 As a special exception, you can use a bitmap subtitle stream as input: it
978 will be converted into a video with the same size as the largest video in
979 the file, or 720×576 if no video is present. Note that this is an
980 experimental and temporary solution. It will be removed once libavfilter has
981 proper support for subtitles.
983 For example, to hardcode subtitles on top of a DVB-T recording stored in
984 MPEG-TS format, delaying the subtitles by 1 second:
986 ffmpeg -i input.ts -filter_complex \
987 '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
988 -sn -map '#0x2dc' output.mkv
990 (0x2d0, 0x2dc and 0x2ef are the MPEG-TS PIDs of respectively the video,
991 audio and subtitles streams; 0:0, 0:3 and 0:7 would have worked too)
993 @section Preset files
994 A preset file contains a sequence of @var{option}=@var{value} pairs,
995 one for each line, specifying a sequence of options which would be
996 awkward to specify on the command line. Lines starting with the hash
997 ('#') character are ignored and are used to provide comments. Check
998 the @file{presets} directory in the FFmpeg source tree for examples.
1000 Preset files are specified with the @code{vpre}, @code{apre},
1001 @code{spre}, and @code{fpre} options. The @code{fpre} option takes the
1002 filename of the preset instead of a preset name as input and can be
1003 used for any kind of codec. For the @code{vpre}, @code{apre}, and
1004 @code{spre} options, the options specified in a preset file are
1005 applied to the currently selected codec of the same type as the preset
1008 The argument passed to the @code{vpre}, @code{apre}, and @code{spre}
1009 preset options identifies the preset file to use according to the
1012 First ffmpeg searches for a file named @var{arg}.ffpreset in the
1013 directories @file{$FFMPEG_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
1014 the datadir defined at configuration time (usually @file{PREFIX/share/ffmpeg})
1015 or in a @file{ffpresets} folder along the executable on win32,
1016 in that order. For example, if the argument is @code{libvpx-1080p}, it will
1017 search for the file @file{libvpx-1080p.ffpreset}.
1019 If no such file is found, then ffmpeg will search for a file named
1020 @var{codec_name}-@var{arg}.ffpreset in the above-mentioned
1021 directories, where @var{codec_name} is the name of the codec to which
1022 the preset file options will be applied. For example, if you select
1023 the video codec with @code{-vcodec libvpx} and use @code{-vpre 1080p},
1024 then it will search for the file @file{libvpx-1080p.ffpreset}.
1032 For streaming at very low bitrate application, use a low frame rate
1033 and a small GOP size. This is especially true for RealVideo where
1034 the Linux player does not seem to be very fast, so it can miss
1035 frames. An example is:
1038 ffmpeg -g 3 -r 3 -t 10 -b:v 50k -s qcif -f rv10 /tmp/b.rm
1042 The parameter 'q' which is displayed while encoding is the current
1043 quantizer. The value 1 indicates that a very good quality could
1044 be achieved. The value 31 indicates the worst quality. If q=31 appears
1045 too often, it means that the encoder cannot compress enough to meet
1046 your bitrate. You must either increase the bitrate, decrease the
1047 frame rate or decrease the frame size.
1050 If your computer is not fast enough, you can speed up the
1051 compression at the expense of the compression ratio. You can use
1052 '-me zero' to speed up motion estimation, and '-g 0' to disable
1053 motion estimation completely (you have only I-frames, which means it
1054 is about as good as JPEG compression).
1057 To have very low audio bitrates, reduce the sampling frequency
1058 (down to 22050 Hz for MPEG audio, 22050 or 11025 for AC-3).
1061 To have a constant quality (but a variable bitrate), use the option
1062 '-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst
1069 @c man begin EXAMPLES
1071 @section Preset files
1073 A preset file contains a sequence of @var{option=value} pairs, one for
1074 each line, specifying a sequence of options which can be specified also on
1075 the command line. Lines starting with the hash ('#') character are ignored and
1076 are used to provide comments. Empty lines are also ignored. Check the
1077 @file{presets} directory in the FFmpeg source tree for examples.
1079 Preset files are specified with the @code{pre} option, this option takes a
1080 preset name as input. FFmpeg searches for a file named @var{preset_name}.avpreset in
1081 the directories @file{$AVCONV_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
1082 the data directory defined at configuration time (usually @file{$PREFIX/share/ffmpeg})
1083 in that order. For example, if the argument is @code{libx264-max}, it will
1084 search for the file @file{libx264-max.avpreset}.
1086 @section Video and Audio grabbing
1088 If you specify the input format and device then ffmpeg can grab video
1092 ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
1095 Or with an ALSA audio source (mono input, card id 1) instead of OSS:
1097 ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg
1100 Note that you must activate the right video source and channel before
1101 launching ffmpeg with any TV viewer such as
1102 @uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also
1103 have to set the audio recording levels correctly with a
1106 @section X11 grabbing
1108 Grab the X11 display with ffmpeg via
1111 ffmpeg -f x11grab -s cif -r 25 -i :0.0 /tmp/out.mpg
1114 0.0 is display.screen number of your X11 server, same as
1115 the DISPLAY environment variable.
1118 ffmpeg -f x11grab -s cif -r 25 -i :0.0+10,20 /tmp/out.mpg
1121 0.0 is display.screen number of your X11 server, same as the DISPLAY environment
1122 variable. 10 is the x-offset and 20 the y-offset for the grabbing.
1124 @section Video and Audio file format conversion
1126 Any supported file format and protocol can serve as input to ffmpeg:
1131 You can use YUV files as input:
1134 ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
1137 It will use the files:
1139 /tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
1140 /tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
1143 The Y files use twice the resolution of the U and V files. They are
1144 raw files, without header. They can be generated by all decent video
1145 decoders. You must specify the size of the image with the @option{-s} option
1146 if ffmpeg cannot guess it.
1149 You can input from a raw YUV420P file:
1152 ffmpeg -i /tmp/test.yuv /tmp/out.avi
1155 test.yuv is a file containing raw YUV planar data. Each frame is composed
1156 of the Y plane followed by the U and V planes at half vertical and
1157 horizontal resolution.
1160 You can output to a raw YUV420P file:
1163 ffmpeg -i mydivx.avi hugefile.yuv
1167 You can set several input files and output files:
1170 ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
1173 Converts the audio file a.wav and the raw YUV video file a.yuv
1177 You can also do audio and video conversions at the same time:
1180 ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
1183 Converts a.wav to MPEG audio at 22050 Hz sample rate.
1186 You can encode to several formats at the same time and define a
1187 mapping from input stream to output streams:
1190 ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2
1193 Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
1194 file:index' specifies which input stream is used for each output
1195 stream, in the order of the definition of output streams.
1198 You can transcode decrypted VOBs:
1201 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
1204 This is a typical DVD ripping example; the input is a VOB file, the
1205 output an AVI file with MPEG-4 video and MP3 audio. Note that in this
1206 command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
1207 GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
1208 input video. Furthermore, the audio stream is MP3-encoded so you need
1209 to enable LAME support by passing @code{--enable-libmp3lame} to configure.
1210 The mapping is particularly useful for DVD transcoding
1211 to get the desired audio language.
1213 NOTE: To see the supported input formats, use @code{ffmpeg -formats}.
1216 You can extract images from a video, or create a video from many images:
1218 For extracting images from a video:
1220 ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
1223 This will extract one video frame per second from the video and will
1224 output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg},
1225 etc. Images will be rescaled to fit the new WxH values.
1227 If you want to extract just a limited number of frames, you can use the
1228 above command in combination with the -vframes or -t option, or in
1229 combination with -ss to start extracting from a certain point in time.
1231 For creating a video from many images:
1233 ffmpeg -f image2 -i foo-%03d.jpeg -r 12 -s WxH foo.avi
1236 The syntax @code{foo-%03d.jpeg} specifies to use a decimal number
1237 composed of three digits padded with zeroes to express the sequence
1238 number. It is the same syntax supported by the C printf function, but
1239 only formats accepting a normal integer are suitable.
1241 When importing an image sequence, -i also supports expanding
1242 shell-like wildcard patterns (globbing) internally, by selecting the
1243 image2-specific @code{-pattern_type glob} option.
1245 For example, for creating a video from filenames matching the glob pattern
1248 ffmpeg -f image2 -pattern_type glob -i 'foo-*.jpeg' -r 12 -s WxH foo.avi
1252 You can put many streams of the same type in the output:
1255 ffmpeg -i test1.avi -i test2.avi -map 0.3 -map 0.2 -map 0.1 -map 0.0 -c copy test12.nut
1258 The resulting output file @file{test12.avi} will contain first four streams from
1259 the input file in reverse order.
1262 To force CBR video output:
1264 ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
1268 The four options lmin, lmax, mblmin and mblmax use 'lambda' units,
1269 but you may use the QP2LAMBDA constant to easily convert from 'q' units:
1271 ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
1277 @include syntax.texi
1279 @include decoders.texi
1280 @include encoders.texi
1281 @include demuxers.texi
1282 @include muxers.texi
1283 @include indevs.texi
1284 @include outdevs.texi
1285 @include protocols.texi
1286 @include bitstream_filters.texi
1287 @include filters.texi
1288 @include metadata.texi
1293 @settitle ffmpeg video converter
1295 @c man begin SEEALSO
1296 ffplay(1), ffprobe(1), ffserver(1) and the FFmpeg HTML documentation
1299 @c man begin AUTHORS