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Section: (1)


ffmpeg - ffmpeg video converter 


ffmpeg [global_options] {[input_file_options] -i input_url} ... {[output_file_options] output_url} ... 


ffmpeg is a very fast video and audio converter that can also grab froma live audio/video source. It can also convert between arbitrary samplerates and resize video on the fly with a high quality polyphase filter.

ffmpeg reads from an arbitrary number of input ``files'' (which can be regularfiles, pipes, network streams, grabbing devices, etc.), specified by the"-i" option, and writes to an arbitrary number of output ``files'', which arespecified by a plain output url. Anything found on the command line whichcannot be interpreted as an option is considered to be an output url.

Each input or output url can, in principle, contain any number of streams ofdifferent types (video/audio/subtitle/attachment/data). The allowed number and/ortypes of streams may be limited by the container format. Selecting whichstreams from which inputs will go into which output is either done automaticallyor with the "-map" option (see the Stream selection chapter).

To refer to input files in options, you must use their indices (0-based). E.g.the first input file is 0, the second is 1, etc. Similarly, streamswithin a file are referred to by their indices. E.g. "2:3" refers to thefourth stream in the third input file. Also see the Stream specifiers chapter.

As a general rule, options are applied to the next specifiedfile. Therefore, order is important, and you can have the sameoption on the command line multiple times. Each occurrence isthen applied to the next input or output file.Exceptions from this rule are the global options (e.g. verbosity level),which should be specified first.

Do not mix input and output files --- first specify all input files, then alloutput files. Also do not mix options which belong to different files. Alloptions apply ONLY to the next input or output file and are reset between files.

To set the video bitrate of the output file to 64 kbit/s:

        ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi
To force the frame rate of the output file to 24 fps:

        ffmpeg -i input.avi -r 24 output.avi
To force the frame rate of the input file (valid for raw formats only)to 1 fps and the frame rate of the output file to 24 fps:

        ffmpeg -r 1 -i input.m2v -r 24 output.avi

The format option may be needed for raw input files. 


The transcoding process in ffmpeg for each output can be described bythe following diagram:

         _______              ______________        |       |            |              |        | input |  demuxer   | encoded data |   decoder        | file  | ---------> | packets      | -----+        |_______|            |______________|      |                                                   v                                               _________                                              |         |                                              | decoded |                                              | frames  |                                              |_________|         ________             ______________       |        |        |           |              |      |        | output | <-------- | encoded data | <----+        | file   |   muxer   | packets      |   encoder        |________|           |______________|

ffmpeg calls the libavformat library (containing demuxers) to readinput files and get packets containing encoded data from them. When there aremultiple input files, ffmpeg tries to keep them synchronized bytracking lowest timestamp on any active input stream.

Encoded packets are then passed to the decoder (unless streamcopy is selectedfor the stream, see further for a description). The decoder producesuncompressed frames (raw video/PCM audio/...) which can be processed further byfiltering (see next section). After filtering, the frames are passed to theencoder, which encodes them and outputs encoded packets. Finally those arepassed to the muxer, which writes the encoded packets to the output file. 


Before encoding, ffmpeg can process raw audio and video frames usingfilters from the libavfilter library. Several chained filters form a filtergraph. ffmpeg distinguishes between two types of filtergraphs:simple and complex.

Simple filtergraphs

Simple filtergraphs are those that have exactly one input and output, both ofthe same type. In the above diagram they can be represented by simply insertingan additional step between decoding and encoding:

         _________                        ______________        |         |                      |              |        | decoded |                      | encoded data |        | frames  |\                   _ | packets      |        |_________| \                  /||______________|                     \   __________   /          simple     _\||          | /  encoder          filtergraph   | filtered |/                        | frames   |                        |__________|

Simple filtergraphs are configured with the per-stream -filter option(with -vf and -af aliases for video and audio respectively).A simple filtergraph for video can look for example like this:

         _______        _____________        _______        ________        |       |      |             |      |       |      |        |        | input | ---> | deinterlace | ---> | scale | ---> | output |        |_______|      |_____________|      |_______|      |________|

Note that some filters change frame properties but not frame contents. E.g. the"fps" filter in the example above changes number of frames, but does nottouch the frame contents. Another example is the "setpts" filter, whichonly sets timestamps and otherwise passes the frames unchanged.

Complex filtergraphs

Complex filtergraphs are those which cannot be described as simply a linearprocessing chain applied to one stream. This is the case, for example, when the graph hasmore than one input and/or output, or when output stream type is different frominput. They can be represented with the following diagram:

         _________        |         |        | input 0 |\                    __________        |_________| \                  |          |                     \   _________    /| output 0 |                      \ |         |  / |__________|         _________     \| complex | /        |         |     |         |/        | input 1 |---->| filter  |\        |_________|     |         | \   __________                       /| graph   |  \ |          |                      / |         |   \| output 1 |         _________   /  |_________|    |__________|        |         | /        | input 2 |/        |_________|

Complex filtergraphs are configured with the -filter_complex option.Note that this option is global, since a complex filtergraph, by its nature,cannot be unambiguously associated with a single stream or file.

The -lavfi option is equivalent to -filter_complex.

A trivial example of a complex filtergraph is the "overlay" filter, whichhas two video inputs and one video output, containing one video overlaid on topof the other. Its audio counterpart is the "amix" filter. 

Stream copy

Stream copy is a mode selected by supplying the "copy" parameter to the-codec option. It makes ffmpeg omit the decoding and encodingstep for the specified stream, so it does only demuxing and muxing. It is usefulfor changing the container format or modifying container-level metadata. Thediagram above will, in this case, simplify to this:

         _______              ______________            ________        |       |            |              |          |        |        | input |  demuxer   | encoded data |  muxer   | output |        | file  | ---------> | packets      | -------> | file   |        |_______|            |______________|          |________|

Since there is no decoding or encoding, it is very fast and there is no qualityloss. However, it might not work in some cases because of many factors. Applyingfilters is obviously also impossible, since filters work on uncompressed data. 


ffmpeg provides the "-map" option for manual control of stream selection in eachoutput file. Users can skip "-map" and let ffmpeg perform automatic stream selection asdescribed below. The "-vn / -an / -sn / -dn" options can be used to skip inclusion ofvideo, audio, subtitle and data streams respectively, whether manually mapped or automaticallyselected, except for those streams which are outputs of complex filtergraphs. 


The sub-sections that follow describe the various rules that are involved in stream selection.The examples that follow next show how these rules are applied in practice.

While every effort is made to accurately reflect the behavior of the program, FFmpeg is undercontinuous development and the code may have changed since the time of this writing.

Automatic stream selection

In the absence of any map options for a particular output file, ffmpeg inspects the outputformat to check which type of streams can be included in it, viz. video, audio and/orsubtitles. For each acceptable stream type, ffmpeg will pick one stream, when available,from among all the inputs.

It will select that stream based upon the following criteria:

for video, it is the stream with the highest resolution,
for audio, it is the stream with the most channels,
for subtitles, it is the first subtitle stream found but there's a caveat.The output format's default subtitle encoder can be either text-based or image-based,and only a subtitle stream of the same type will be chosen.

In the case where several streams of the same type rate equally, the stream with the lowestindex is chosen.

Data or attachment streams are not automatically selected and can only be includedusing "-map".

Manual stream selection

When "-map" is used, only user-mapped streams are included in that output file,with one possible exception for filtergraph outputs described below.

Complex filtergraphs

If there are any complex filtergraph output streams with unlabeled pads, they will be addedto the first output file. This will lead to a fatal error if the stream type is not supportedby the output format. In the absence of the map option, the inclusion of these streams leadsto the automatic stream selection of their types being skipped. If map options are present,these filtergraph streams are included in addition to the mapped streams.

Complex filtergraph output streams with labeled pads must be mapped once and exactly once.

Stream handling

Stream handling is independent of stream selection, with an exception for subtitles describedbelow. Stream handling is set via the "-codec" option addressed to streams within aspecific output file. In particular, codec options are applied by ffmpeg after thestream selection process and thus do not influence the latter. If no "-codec" option isspecified for a stream type, ffmpeg will select the default encoder registered by the outputfile muxer.

An exception exists for subtitles. If a subtitle encoder is specified for an output file, thefirst subtitle stream found of any type, text or image, will be included. ffmpeg does not validateif the specified encoder can convert the selected stream or if the converted stream is acceptablewithin the output format. This applies generally as well: when the user sets an encoder manually,the stream selection process cannot check if the encoded stream can be muxed into the output file.If it cannot, ffmpeg will abort and all output files will fail to be processed. 


The following examples illustrate the behavior, quirks and limitations of ffmpeg's streamselection methods.

They assume the following three input files.

        input file 'A.avi'              stream 0: video 640x360              stream 1: audio 2 channels                input file 'B.mp4'              stream 0: video 1920x1080              stream 1: audio 2 channels              stream 2: subtitles (text)              stream 3: audio 5.1 channels              stream 4: subtitles (text)                input file 'C.mkv'              stream 0: video 1280x720              stream 1: audio 2 channels              stream 2: subtitles (image)

Example: automatic stream selection

        ffmpeg -i A.avi -i B.mp4 out1.mkv out2.wav -map 1:a -c:a copy

There are three output files specified, and for the first two, no "-map" optionsare set, so ffmpeg will select streams for these two files automatically.

out1.mkv is a Matroska container file and accepts video, audio and subtitle streams,so ffmpeg will try to select one of each type.For video, it will select "stream 0" from B.mp4, which has the highestresolution among all the input video streams.For audio, it will select "stream 3" from B.mp4, since it has the greatestnumber of channels.For subtitles, it will select "stream 2" from B.mp4, which is the first subtitlestream from among A.avi and B.mp4.

out2.wav accepts only audio streams, so only "stream 3" from B.mp4 isselected.

For, since a "-map" option is set, no automatic stream selection willoccur. The "-map 1:a" option will select all audio streams from the second inputB.mp4. No other streams will be included in this output file.

For the first two outputs, all included streams will be transcoded. The encoders chosen willbe the default ones registered by each output format, which may not match the codec of theselected input streams.

For the third output, codec option for audio streams has been setto "copy", so no decoding-filtering-encoding operations will occur, or can occur.Packets of selected streams shall be conveyed from the input file and muxed within the outputfile.

Example: automatic subtitles selection

        ffmpeg -i C.mkv out1.mkv -c:s dvdsub -an out2.mkv

Although out1.mkv is a Matroska container file which accepts subtitle streams, only avideo and audio stream shall be selected. The subtitle stream of C.mkv is image-basedand the default subtitle encoder of the Matroska muxer is text-based, so a transcode operationfor the subtitles is expected to fail and hence the stream isn't selected. However, inout2.mkv, a subtitle encoder is specified in the command and so, the subtitle stream isselected, in addition to the video stream. The presence of "-an" disables audio streamselection for out2.mkv.

Example: unlabeled filtergraph outputs

        ffmpeg -i A.avi -i C.mkv -i B.mp4 -filter_complex "overlay" out1.mp4

A filtergraph is setup here using the "-filter_complex" option and consists of a singlevideo filter. The "overlay" filter requires exactly two video inputs, but none arespecified, so the first two available video streams are used, those of A.avi andC.mkv. The output pad of the filter has no label and so is sent to the first output fileout1.mp4. Due to this, automatic selection of the video stream is skipped, which wouldhave selected the stream in B.mp4. The audio stream with most channels viz. "stream 3"in B.mp4, is chosen automatically. No subtitle stream is chosen however, since the MP4format has no default subtitle encoder registered, and the user hasn't specified a subtitle encoder.

The 2nd output file,, only accepts text-based subtitle streams. So, even thoughthe first subtitle stream available belongs to C.mkv, it is image-based and hence skipped.The selected stream, "stream 2" in B.mp4, is the first text-based subtitle stream.

Example: labeled filtergraph outputs

        ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0[outv];overlay;aresample" \               -map '[outv]' -an        out1.mp4 \                                        out2.mkv \               -map '[outv]' -map 1:a:0 out3.mkv

The above command will fail, as the output pad labelled "[outv]" has been mapped twice.None of the output files shall be processed.

        ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0[outv];overlay;aresample" \               -an        out1.mp4 \                          out2.mkv \               -map 1:a:0 out3.mkv

This command above will also fail as the hue filter output has a label, "[outv]",and hasn't been mapped anywhere.

The command should be modified as follows,

        ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0,split=2[outv1][outv2];overlay;aresample" \                -map '[outv1]' -an        out1.mp4 \                                          out2.mkv \                -map '[outv2]' -map 1:a:0 out3.mkv

The video stream from B.mp4 is sent to the hue filter, whose output is cloned once usingthe split filter, and both outputs labelled. Then a copy each is mapped to the first and thirdoutput files.

The overlay filter, requiring two video inputs, uses the first two unused video streams. Thoseare the streams from A.avi and C.mkv. The overlay output isn't labelled, so it issent to the first output file out1.mp4, regardless of the presence of the "-map" option.

The aresample filter is sent the first unused audio stream, that of A.avi. Since this filteroutput is also unlabelled, it too is mapped to the first output file. The presence of "-an"only suppresses automatic or manual stream selection of audio streams, not outputs sent fromfiltergraphs. Both these mapped streams shall be ordered before the mapped stream in out1.mp4.

The video, audio and subtitle streams mapped to "out2.mkv" are entirely determined byautomatic stream selection.

out3.mkv consists of the cloned video output from the hue filter and the first audiostream from B.mp4. 


All the numerical options, if not specified otherwise, accept a stringrepresenting a number as input, which may be followed by one of the SIunit prefixes, for example: 'K', 'M', or 'G'.

If 'i' is appended to the SI unit prefix, the complete prefix will beinterpreted as a unit prefix for binary multiples, which are based onpowers of 1024 instead of powers of 1000. Appending 'B' to the SI unitprefix multiplies the value by 8. This allows using, for example:'KB', 'MiB', 'G' and 'B' as number suffixes.

Options which do not take arguments are boolean options, and set thecorresponding value to true. They can be set to false by prefixingthe option name with ``no''. For example using ``-nofoo''will set the boolean option with name ``foo'' to false. 

Stream specifiers

Some options are applied per-stream, e.g. bitrate or codec. Stream specifiersare used to precisely specify which stream(s) a given option belongs to.

A stream specifier is a string generally appended to the option name andseparated from it by a colon. E.g. "-codec:a:1 ac3" contains the"a:1" stream specifier, which matches the second audio stream. Therefore, itwould select the ac3 codec for the second audio stream.

A stream specifier can match several streams, so that the option is applied to allof them. E.g. the stream specifier in "-b:a 128k" matches all audiostreams.

An empty stream specifier matches all streams. For example, "-codec copy"or "-codec: copy" would copy all the streams without reencoding.

Possible forms of stream specifiers are:

Matches the stream with this index. E.g. "-threads:1 4" would set thethread count for the second stream to 4.
stream_type is one of following: 'v' or 'V' for video, 'a' for audio, 's'for subtitle, 'd' for data, and 't' for attachments. 'v' matches all videostreams, 'V' only matches video streams which are not attached pictures, videothumbnails or cover arts. If stream_index is given, then it matchesstream number stream_index of this type. Otherwise, it matches allstreams of this type.
p:program_id[:stream_index] or p:program_id[:stream_type[:stream_index]] or
p:program_id:m:key[:value]In first version, if stream_index is given, then it matches the stream with number stream_indexin the program with the id program_id. Otherwise, it matches all streams in theprogram. In the second version, stream_type is one of following: 'v' for video, 'a' for audio, 's'for subtitle, 'd' for data. If stream_index is also given, then it matchesstream number stream_index of this type in the program with the id program_id.Otherwise, if only stream_type is given, it matches allstreams of this type in the program with the id program_id.In the third version matches streams in the program with the id program_id with the metadatatag key having the specified value. Ifvalue is not given, matches streams that contain the given tag with anyvalue.
#stream_id or i:stream_id
Match the stream by stream id (e.g. PID in MPEG-TS container).
Matches streams with the metadata tag key having the specified value. Ifvalue is not given, matches streams that contain the given tag with anyvalue.
Matches streams with usable configuration, the codec must be defined and theessential information such as video dimension or audio sample rate must be present.

Note that in ffmpeg, matching by metadata will only work properly forinput files.


Generic options

These options are shared amongst the ff* tools.
Show license.
-h, -?, -help, --help [arg]
Show help. An optional parameter may be specified to print help about a specificitem. If no argument is specified, only basic (non advanced) tooloptions are shown.

Possible values of arg are:

Print advanced tool options in addition to the basic tool options.
Print complete list of options, including shared and private optionsfor encoders, decoders, demuxers, muxers, filters, etc.
Print detailed information about the decoder named decoder_name. Use the-decoders option to get a list of all decoders.
Print detailed information about the encoder named encoder_name. Use the-encoders option to get a list of all encoders.
Print detailed information about the demuxer named demuxer_name. Use the-formats option to get a list of all demuxers and muxers.
Print detailed information about the muxer named muxer_name. Use the-formats option to get a list of all muxers and demuxers.
Print detailed information about the filter name filter_name. Use the-filters option to get a list of all filters.
Show version.
Show available formats (including devices).
Show available demuxers.
Show available muxers.
Show available devices.
Show all codecs known to libavcodec.

Note that the term 'codec' is used throughout this documentation as a shortcutfor what is more correctly called a media bitstream format.

Show available decoders.
Show all available encoders.
Show available bitstream filters.
Show available protocols.
Show available libavfilter filters.
Show available pixel formats.
Show available sample formats.
Show channel names and standard channel layouts.
Show recognized color names.
-sources device[,opt1=val1[,opt2=val2]...]
Show autodetected sources of the input device.Some devices may provide system-dependent source names that cannot be autodetected.The returned list cannot be assumed to be always complete.

        ffmpeg -sources pulse,server=
-sinks device[,opt1=val1[,opt2=val2]...]
Show autodetected sinks of the output device.Some devices may provide system-dependent sink names that cannot be autodetected.The returned list cannot be assumed to be always complete.

        ffmpeg -sinks pulse,server=
-loglevel [flags+]loglevel | -v [flags+]loglevel
Set logging level and flags used by the library.

The optional flags prefix can consist of the following values:

Indicates that repeated log output should not be compressed to the first lineand the ``Last message repeated n times'' line will be omitted.
Indicates that log output should add a "[level]" prefix to each messageline. This can be used as an alternative to log coloring, e.g. when dumping thelog to file.

Flags can also be used alone by adding a '+'/'-' prefix to set/reset a singleflag without affecting other flags or changing loglevel. Whensetting both flags and loglevel, a '+' separator is expectedbetween the last flags value and before loglevel.

loglevel is a string or a number containing one of the following values:

quiet, -8
Show nothing at all; be silent.
panic, 0
Only show fatal errors which could lead the process to crash, such asan assertion failure. This is not currently used for anything.
fatal, 8
Only show fatal errors. These are errors after which the process absolutelycannot continue.
error, 16
Show all errors, including ones which can be recovered from.
warning, 24
Show all warnings and errors. Any message related to possiblyincorrect or unexpected events will be shown.
info, 32
Show informative messages during processing. This is in addition towarnings and errors. This is the default value.
verbose, 40
Same as "info", except more verbose.
debug, 48
Show everything, including debugging information.
trace, 56

For example to enable repeated log output, add the "level" prefix, and setloglevel to "verbose":

        ffmpeg -loglevel repeat+level+verbose -i input output

Another example that enables repeated log output without affecting currentstate of "level" prefix flag or loglevel:

        ffmpeg [...] -loglevel +repeat

By default the program logs to stderr. If coloring is supported by theterminal, colors are used to mark errors and warnings. Log coloringcan be disabled setting the environment variableAV_LOG_FORCE_NOCOLOR or NO_COLOR, or can be forced settingthe environment variable AV_LOG_FORCE_COLOR.The use of the environment variable NO_COLOR is deprecated andwill be dropped in a future FFmpeg version.

Dump full command line and console output to a file named"program-YYYYMMDD-HHMMSS.log" in the currentdirectory.This file can be useful for bug reports.It also implies "-loglevel verbose".

Setting the environment variable FFREPORT to any value has thesame effect. If the value is a ':'-separated key=value sequence, theseoptions will affect the report; option values must be escaped if theycontain special characters or the options delimiter ':' (see the``Quoting and escaping'' section in the ffmpeg-utils manual).

The following options are recognized:

set the file name to use for the report; %p is expanded to the nameof the program, %t is expanded to a timestamp, "%%" is expandedto a plain "%"
set the log verbosity level using a numerical value (see "-loglevel").

For example, to output a report to a file named ffreport.logusing a log level of 32 (alias for log level "info"):

        FFREPORT=file=ffreport.log:level=32 ffmpeg -i input output

Errors in parsing the environment variable are not fatal, and will notappear in the report.

Suppress printing banner.

All FFmpeg tools will normally show a copyright notice, build optionsand library versions. This option can be used to suppress printingthis information.

-cpuflags flags (global)
Allows setting and clearing cpu flags. This option is intendedfor testing. Do not use it unless you know what you're doing.

        ffmpeg -cpuflags -sse+mmx ...        ffmpeg -cpuflags mmx ...        ffmpeg -cpuflags 0 ...

Possible flags for this option are:

Specific Processors


These options are provided directly by the libavformat, libavdevice andlibavcodec libraries. To see the list of available AVOptions, use the-help option. They are separated into two categories:
These options can be set for any container, codec or device. Generic optionsare listed under AVFormatContext options for containers/devices and underAVCodecContext options for codecs.
These options are specific to the given container, device or codec. Privateoptions are listed under their corresponding containers/devices/codecs.

For example to write an ID3v2.3 header instead of a default ID3v2.4 toan MP3 file, use the id3v2_version private option of the MP3muxer:

        ffmpeg -i input.flac -id3v2_version 3 out.mp3

All codec AVOptions are per-stream, and thus a stream specifiershould be attached to them.

Note: the -nooption syntax cannot be used for booleanAVOptions, use -option 0/-option 1.

Note: the old undocumented way of specifying per-stream AVOptions byprepending v/a/s to the options name is now obsolete and will beremoved soon. 

Main options

-f fmt (input/output)
Force input or output file format. The format is normally auto detected for inputfiles and guessed from the file extension for output files, so this option is notneeded in most cases.
-i url (input)
input file url
-y (global)
Overwrite output files without asking.
-n (global)
Do not overwrite output files, and exit immediately if a specifiedoutput file already exists.
-stream_loop number (input)
Set number of times input stream shall be looped. Loop 0 means no loop,loop -1 means infinite loop.
-c[:stream_specifier] codec (input/output,per-stream)
-codec[:stream_specifier] codec (input/output,per-stream)
Select an encoder (when used before an output file) or a decoder (when usedbefore an input file) for one or more streams. codec is the name of adecoder/encoder or a special value "copy" (output only) to indicate thatthe stream is not to be re-encoded.

For example

        ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT

encodes all video streams with libx264 and copies all audio streams.

For each stream, the last matching "c" option is applied, so

        ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT

will copy all the streams except the second video, which will be encoded withlibx264, and the 138th audio, which will be encoded with libvorbis.

-t duration (input/output)
When used as an input option (before "-i"), limit the duration ofdata read from the input file.

When used as an output option (before an output url), stop writing theoutput after its duration reaches duration.

duration must be a time duration specification,see the Time duration section in the ffmpeg-utils(1) manual.

-to and -t are mutually exclusive and -t has priority.

-to position (input/output)
Stop writing the output or reading the input at position.position must be a time duration specification,see the Time duration section in the ffmpeg-utils(1) manual.

-to and -t are mutually exclusive and -t has priority.

-fs limit_size (output)
Set the file size limit, expressed in bytes. No further chunk of bytes is writtenafter the limit is exceeded. The size of the output file is slightly more than therequested file size.
-ss position (input/output)
When used as an input option (before "-i"), seeks in this input file toposition. Note that in most formats it is not possible to seek exactly,so ffmpeg will seek to the closest seek point before position.When transcoding and -accurate_seek is enabled (the default), thisextra segment between the seek point and position will be decoded anddiscarded. When doing stream copy or when -noaccurate_seek is used, itwill be preserved.

When used as an output option (before an output url), decodes but discardsinput until the timestamps reach position.

position must be a time duration specification,see the Time duration section in the ffmpeg-utils(1) manual.

-sseof position (input)
Like the "-ss" option but relative to the ``end of file''. That is negativevalues are earlier in the file, 0 is at EOF.
-itsoffset offset (input)
Set the input time offset.

offset must be a time duration specification,see the Time duration section in the ffmpeg-utils(1) manual.

The offset is added to the timestamps of the input files. Specifyinga positive offset means that the corresponding streams are delayed bythe time duration specified in offset.

-timestamp date (output)
Set the recording timestamp in the container.

date must be a date specification,see the Date section in the ffmpeg-utils(1) manual.

-metadata[:metadata_specifier] key=value (output,per-metadata)
Set a metadata key/value pair.

An optional metadata_specifier may be given to set metadataon streams, chapters or programs. See "-map_metadata"documentation for details.

This option overrides metadata set with "-map_metadata". It isalso possible to delete metadata by using an empty value.

For example, for setting the title in the output file:

        ffmpeg -i in.avi -metadata title="my title" out.flv

To set the language of the first audio stream:

        ffmpeg -i INPUT -metadata:s:a:0 language=eng OUTPUT
-disposition[:stream_specifier] value (output,per-stream)
Sets the disposition for a stream.

This option overrides the disposition copied from the input stream. It is alsopossible to delete the disposition by setting it to 0.

The following dispositions are recognized:


For example, to make the second audio stream the default stream:

        ffmpeg -i in.mkv -c copy -disposition:a:1 default out.mkv

To make the second subtitle stream the default stream and remove the defaultdisposition from the first subtitle stream:

        ffmpeg -i in.mkv -c copy -disposition:s:0 0 -disposition:s:1 default out.mkv

To add an embedded cover/thumbnail:

        ffmpeg -i in.mp4 -i IMAGE -map 0 -map 1 -c copy -c:v:1 png -disposition:v:1 attached_pic out.mp4

Not all muxers support embedded thumbnails, and those who do, only support a few formats, like JPEG or PNG.

-program [title=title:][program_num=program_num:]st=stream[:st=stream...] (output)
Creates a program with the specified title, program_num and adds the specifiedstream(s) to it.
-target type (output)
Specify target file type ("vcd", "svcd", "dvd", "dv","dv50"). type may be prefixed with "pal-", "ntsc-" or"film-" to use the corresponding standard. All the format options(bitrate, codecs, buffer sizes) are then set automatically. You can just type:

        ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg

Nevertheless you can specify additional options as long as you knowthey do not conflict with the standard, as in:

        ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
-dn (output)
Disable data recording. For full manual control see the "-map"option.
-dframes number (output)
Set the number of data frames to output. This is an obsolete alias for"-frames:d", which you should use instead.
-frames[:stream_specifier] framecount (output,per-stream)
Stop writing to the stream after framecount frames.
-q[:stream_specifier] q (output,per-stream)
-qscale[:stream_specifier] q (output,per-stream)
Use fixed quality scale (VBR). The meaning of q/qscale iscodec-dependent.If qscale is used without a stream_specifier then it applies onlyto the video stream, this is to maintain compatibility with previous behaviorand as specifying the same codec specific value to 2 different codecs that isaudio and video generally is not what is intended when no stream_specifier isused.
-filter[:stream_specifier] filtergraph (output,per-stream)
Create the filtergraph specified by filtergraph and use it tofilter the stream.

filtergraph is a description of the filtergraph to apply tothe stream, and must have a single input and a single output of thesame type of the stream. In the filtergraph, the input is associatedto the label "in", and the output to the label "out". Seethe ffmpeg-filters manual for more information about the filtergraphsyntax.

See the -filter_complex option if youwant to create filtergraphs with multiple inputs and/or outputs.

-filter_script[:stream_specifier] filename (output,per-stream)
This option is similar to -filter, the only difference is that itsargument is the name of the file from which a filtergraph description is to beread.
-filter_threads nb_threads (global)
Defines how many threads are used to process a filter pipeline. Each pipelinewill produce a thread pool with this many threads available for parallel processing.The default is the number of available CPUs.
-pre[:stream_specifier] preset_name (output,per-stream)
Specify the preset for matching stream(s).
-stats (global)
Print encoding progress/statistics. It is on by default, to explicitlydisable it you need to specify "-nostats".
-progress url (global)
Send program-friendly progress information to url.

Progress information is written approximately every second and at the end ofthe encoding process. It is made of "key=value" lines. keyconsists of only alphanumeric characters. The last key of a sequence ofprogress information is always ``progress''.

Enable interaction on standard input. On by default unless standard input isused as an input. To explicitly disable interaction you need to specify"-nostdin".

Disabling interaction on standard input is useful, for example, ifffmpeg is in the background process group. Roughly the same result canbe achieved with "ffmpeg ... < /dev/null" but it requires ashell.

-debug_ts (global)
Print timestamp information. It is off by default. This option ismostly useful for testing and debugging purposes, and the outputformat may change from one version to another, so it should not beemployed by portable scripts.

See also the option "-fdebug ts".

-attach filename (output)
Add an attachment to the output file. This is supported by a few formatslike Matroska for e.g. fonts used in rendering subtitles. Attachmentsare implemented as a specific type of stream, so this option will adda new stream to the file. It is then possible to use per-stream optionson this stream in the usual way. Attachment streams created with thisoption will be created after all the other streams (i.e. those createdwith "-map" or automatic mappings).

Note that for Matroska you also have to set the mimetype metadata tag:

        ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv

(assuming that the attachment stream will be third in the output file).

-dump_attachment[:stream_specifier] filename (input,per-stream)
Extract the matching attachment stream into a file named filename. Iffilename is empty, then the value of the "filename" metadata tagwill be used.

E.g. to extract the first attachment to a file named 'out.ttf':

        ffmpeg -dump_attachment:t:0 out.ttf -i INPUT

To extract all attachments to files determined by the "filename" tag:

        ffmpeg -dump_attachment:t "" -i INPUT

Technical note --- attachments are implemented as codec extradata, so thisoption can actually be used to extract extradata from any stream, not justattachments.

Disable automatically rotating video based on file metadata.

Video Options

-vframes number (output)
Set the number of video frames to output. This is an obsolete alias for"-frames:v", which you should use instead.
-r[:stream_specifier] fps (input/output,per-stream)
Set frame rate (Hz value, fraction or abbreviation).

As an input option, ignore any timestamps stored in the file and insteadgenerate timestamps assuming constant frame rate fps.This is not the same as the -framerate option used for some input formatslike image2 or v4l2 (it used to be the same in older versions of FFmpeg).If in doubt use -framerate instead of the input option -r.

As an output option, duplicate or drop input frames to achieve constant outputframe rate fps.

-s[:stream_specifier] size (input/output,per-stream)
Set frame size.

As an input option, this is a shortcut for the video_size privateoption, recognized by some demuxers for which the frame size is either notstored in the file or is configurable --- e.g. raw video or video grabbers.

As an output option, this inserts the "scale" video filter to theend of the corresponding filtergraph. Please use the "scale" filterdirectly to insert it at the beginning or some other place.

The format is wxh (default - same as source).

-aspect[:stream_specifier] aspect (output,per-stream)
Set the video display aspect ratio specified by aspect.

aspect can be a floating point number string, or a string of theform num:den, where num and den are thenumerator and denominator of the aspect ratio. For example ``4:3'',``16:9'', ``1.3333'', and ``1.7777'' are valid argument values.

If used together with -vcodec copy, it will affect the aspect ratiostored at container level, but not the aspect ratio stored in encodedframes, if it exists.

-vn (output)
Disable video recording. For full manual control see the "-map"option.
-vcodec codec (output)
Set the video codec. This is an alias for "-codec:v".
-pass[:stream_specifier] n (output,per-stream)
Select the pass number (1 or 2). It is used to do two-passvideo encoding. The statistics of the video are recorded in the firstpass into a log file (see also the option -passlogfile),and in the second pass that log file is used to generate the videoat the exact requested bitrate.On pass 1, you may just deactivate audio and set output to null,examples for Windows and Unix:

        ffmpeg -i -c:v libxvid -pass 1 -an -f rawvideo -y NUL        ffmpeg -i -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null
-passlogfile[:stream_specifier] prefix (output,per-stream)
Set two-pass log file name prefix to prefix, the default file nameprefix is ``ffmpeg2pass''. The complete file name will bePREFIX-N.log, where N is a number specific to the outputstream
-vf filtergraph (output)
Create the filtergraph specified by filtergraph and use it tofilter the stream.

This is an alias for "-filter:v", see the -filter option.


Advanced Video options

-pix_fmt[:stream_specifier] format (input/output,per-stream)
Set pixel format. Use "-pix_fmts" to show all the supportedpixel formats.If the selected pixel format can not be selected, ffmpeg will print awarning and select the best pixel format supported by the encoder.If pix_fmt is prefixed by a "+", ffmpeg will exit with an errorif the requested pixel format can not be selected, and automatic conversionsinside filtergraphs are disabled.If pix_fmt is a single "+", ffmpeg selects the same pixel formatas the input (or graph output) and automatic conversions are disabled.
-sws_flags flags (input/output)
Set SwScaler flags.
-rc_override[:stream_specifier] override (output,per-stream)
Rate control override for specific intervals, formatted as ``int,int,int''list separated with slashes. Two first values are the beginning andend frame numbers, last one is quantizer to use if positive, or qualityfactor if negative.
Force interlacing support in encoder (MPEG-2 and MPEG-4 only).Use this option if your input file is interlaced and you wantto keep the interlaced format for minimum losses.The alternative is to deinterlace the input stream with-deinterlace, but deinterlacing introduces losses.
Calculate PSNR of compressed frames.
Dump video coding statistics to vstats_HHMMSS.log.
-vstats_file file
Dump video coding statistics to file.
-vstats_version file
Specifies which version of the vstats format to use. Default is 2.

version = 1 :

"frame= %5d q= %2.1f PSNR= %6.2f f_size= %6d s_size= %8.0fkB time= %0.3f br= %7.1fkbits/s avg_br= %7.1fkbits/s"

version > 1:

"out= %2d st= %2d frame= %5d q= %2.1f PSNR= %6.2f f_size= %6d s_size= %8.0fkB time= %0.3f br= %7.1fkbits/s avg_br= %7.1fkbits/s"

-top[:stream_specifier] n (output,per-stream)
top=1/bottom=0/auto=-1 field first
-dc precision
-vtag fourcc/tag (output)
Force video tag/fourcc. This is an alias for "-tag:v".
-qphist (global)
Show QP histogram
-vbsf bitstream_filter
Deprecated see -bsf
-force_key_frames[:stream_specifier] time[,time...] (output,per-stream)
-force_key_frames[:stream_specifier] expr:expr (output,per-stream)
Force key frames at the specified timestamps, more precisely at the firstframes after each specified time.

If the argument is prefixed with "expr:", the string expris interpreted like an expression and is evaluated for each frame. Akey frame is forced in case the evaluation is non-zero.

If one of the times is ""chapters"[delta]", it is expanded intothe time of the beginning of all chapters in the file, shifted bydelta, expressed as a time in seconds.This option can be useful to ensure that a seek point is present at achapter mark or any other designated place in the output file.

For example, to insert a key frame at 5 minutes, plus key frames 0.1 secondbefore the beginning of every chapter:

        -force_key_frames 0:05:00,chapters-0.1

The expression in expr can contain the following constants:

the number of current processed frame, starting from 0
the number of forced frames
the number of the previous forced frame, it is "NAN" when nokeyframe was forced yet
the time of the previous forced frame, it is "NAN" when nokeyframe was forced yet
the time of the current processed frame

For example to force a key frame every 5 seconds, you can specify:

        -force_key_frames expr:gte(t,n_forced*5)

To force a key frame 5 seconds after the time of the last forced one,starting from second 13:

        -force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5))

Note that forcing too many keyframes is very harmful for the lookaheadalgorithms of certain encoders: using fixed-GOP options or similarwould be more efficient.

-copyinkf[:stream_specifier] (output,per-stream)
When doing stream copy, copy also non-key frames found at thebeginning.
-init_hw_device type[=name][:device[,key=value...]]
Initialise a new hardware device of type type called name, using thegiven device parameters.If no name is specified it will receive a default name of the form "type%d".

The meaning of device and the following arguments depends on thedevice type:

device is the number of the CUDA device.
device is the number of the Direct3D 9 display adapter.
device is either an X11 display name or a DRM render node.If not specified, it will attempt to open the default X11 display ($DISPLAY)and then the first DRM render node (/dev/dri/renderD128).
device is an X11 display name.If not specified, it will attempt to open the default X11 display ($DISPLAY).
device selects a value in MFX_IMPL_*. Allowed values are:

If not specified, auto_any is used.(Note that it may be easier to achieve the desired result for QSV by creating theplatform-appropriate subdevice (dxva2 or vaapi) and then deriving aQSV device from that.)

device selects the platform and device as platform_index.device_index.

The set of devices can also be filtered using the key-value pairs to find onlydevices matching particular platform or device strings.

The strings usable as filters are:


The indices and filters must together uniquely select a device.


-init_hw_device op