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ffmpeg(1)                                                            ffmpeg(1)




NAME

       ffmpeg - ffmpeg video converter


SYNOPSIS

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


DESCRIPTION

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

       ffmpeg reads from an arbitrary number of input "files" (which can be
       regular files, pipes, network streams, grabbing devices, etc.),
       specified by the "-i" option, and writes to an arbitrary number of
       output "files", which are specified by a plain output url. Anything
       found on the command line which cannot 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 of different types (video/audio/subtitle/attachment/data). The
       allowed number and/or types of streams may be limited by the container
       format. Selecting which streams from which inputs will go into which
       output is either done automatically or 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, streams within a file are referred to by their indices. E.g.
       "2:3" refers to the fourth stream in the third input file. Also see the
       Stream specifiers chapter.

       As a general rule, options are applied to the next specified file.
       Therefore, order is important, and you can have the same option on the
       command line multiple times. Each occurrence is then 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 all output files. Also do not mix options which belong to
       different files. All options apply ONLY to the next input or output
       file and are reset between files.

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

                   ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi

       o   To force the frame rate of the output file to 24 fps:

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

       o   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.


DETAILED DESCRIPTION

       The transcoding process in ffmpeg for each output can be described by
       the 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 read
       input files and get packets containing encoded data from them. When
       there are multiple input files, ffmpeg tries to keep them synchronized
       by tracking lowest timestamp on any active input stream.

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

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

       Simple filtergraphs

       Simple filtergraphs are those that have exactly one input and output,
       both of the same type. In the above diagram they can be represented by
       simply inserting an 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 not touch the frame contents. Another example is the "setpts"
       filter, which only sets timestamps and otherwise passes the frames
       unchanged.

       Complex filtergraphs

       Complex filtergraphs are those which cannot be described as simply a
       linear processing chain applied to one stream. This is the case, for
       example, when the graph has more than one input and/or output, or when
       output stream type is different from input. 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,
       which has two video inputs and one video output, containing one video
       overlaid on top of 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 encoding step for
       the specified stream, so it does only demuxing and muxing. It is useful
       for changing the container format or modifying container-level
       metadata. The diagram 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
       quality loss. However, it might not work in some cases because of many
       factors. Applying filters is obviously also impossible, since filters
       work on uncompressed data.


STREAM SELECTION

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

   Description
       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 under continuous 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 output format to check which type of streams can be
       included in it, viz. video, audio and/or subtitles. 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:

       o   for video, it is the stream with the highest resolution,

       o   for audio, it is the stream with the most channels,

       o   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 lowest index is chosen.

       Data or attachment streams are not automatically selected and can only
       be included using "-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 added to the first output file. This will lead to a
       fatal error if the stream type is not supported by the output format.
       In the absence of the map option, the inclusion of these streams leads
       to 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 described below. Stream handling is set via the "-codec"
       option addressed to streams within a specific output file. In
       particular, codec options are applied by ffmpeg after the stream
       selection process and thus do not influence the latter. If no "-codec"
       option is specified for a stream type, ffmpeg will select the default
       encoder registered by the output file muxer.

       An exception exists for subtitles. If a subtitle encoder is specified
       for an output file, the first subtitle stream found of any type, text
       or image, will be included. ffmpeg does not validate if the specified
       encoder can convert the selected stream or if the converted stream is
       acceptable within 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.

   Examples
       The following examples illustrate the behavior, quirks and limitations
       of ffmpeg's stream selection 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 out3.mov

       There are three output files specified, and for the first two, no
       "-map" options are 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 highest
       resolution among all the input video streams.For audio, it will select
       "stream 3" from B.mp4, since it has the greatest number of channels.For
       subtitles, it will select "stream 2" from B.mp4, which is the first
       subtitle stream from among A.avi and B.mp4.

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

       For out3.mov, since a "-map" option is set, no automatic stream
       selection will occur. The "-map 1:a" option will select all audio
       streams from the second input B.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 will be the default ones registered by each output
       format, which may not match the codec of the selected input streams.

       For the third output, codec option for audio streams has been set to
       "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 output file.

       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 a video and audio stream shall be selected. The subtitle
       stream of C.mkv is image-based and the default subtitle encoder of the
       Matroska muxer is text-based, so a transcode operation for the
       subtitles is expected to fail and hence the stream isn't selected.
       However, in out2.mkv, a subtitle encoder is specified in the command
       and so, the subtitle stream is selected, in addition to the video
       stream. The presence of "-an" disables audio stream selection for
       out2.mkv.

       Example: unlabeled filtergraph outputs

               ffmpeg -i A.avi -i C.mkv -i B.mp4 -filter_complex "overlay" out1.mp4 out2.srt

       A filtergraph is setup here using the "-filter_complex" option and
       consists of a single video filter. The "overlay" filter requires
       exactly two video inputs, but none are specified, so the first two
       available video streams are used, those of A.avi and C.mkv. The output
       pad of the filter has no label and so is sent to the first output file
       out1.mp4. Due to this, automatic selection of the video stream is
       skipped, which would have 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 MP4
       format has no default subtitle encoder registered, and the user hasn't
       specified a subtitle encoder.

       The 2nd output file, out2.srt, only accepts text-based subtitle
       streams. So, even though the 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 using the split filter, and both outputs labelled. Then a
       copy each is mapped to the first and third output files.

       The overlay filter, requiring two video inputs, uses the first two
       unused video streams. Those are the streams from A.avi and C.mkv. The
       overlay output isn't labelled, so it is sent 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 filter output 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 from
       filtergraphs. 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 by automatic stream selection.

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


OPTIONS

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

       If 'i' is appended to the SI unit prefix, the complete prefix will be
       interpreted as a unit prefix for binary multiples, which are based on
       powers of 1024 instead of powers of 1000. Appending 'B' to the SI unit
       prefix 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 the
       corresponding value to true. They can be set to false by prefixing the
       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
       specifiers are used to precisely specify which stream(s) a given option
       belongs to.

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

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

       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:

       stream_index
           Matches the stream with this index. E.g. "-threads:1 4" would set
           the thread count for the second stream to 4. If stream_index is
           used as an additional stream specifier (see below), then it selects
           stream number stream_index from the matching streams. Stream
           numbering is based on the order of the streams as detected by
           libavformat except when a program ID is also specified. In this
           case it is based on the ordering of the streams in the program.

       stream_type[:additional_stream_specifier]
           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 video streams, 'V' only matches video streams which are
           not attached pictures, video thumbnails or cover arts. If
           additional_stream_specifier is used, then it matches streams which
           both have this type and match the additional_stream_specifier.
           Otherwise, it matches all streams of the specified type.

       p:program_id[:additional_stream_specifier]
           Matches streams which are in the program with the id program_id. If
           additional_stream_specifier is used, then it matches streams which
           both are part of the program and match the
           additional_stream_specifier.

       #stream_id or i:stream_id
           Match the stream by stream id (e.g. PID in MPEG-TS container).

       m:key[:value]
           Matches streams with the metadata tag key having the specified
           value. If value is not given, matches streams that contain the
           given tag with any value.

       u   Matches streams with usable configuration, the codec must be
           defined and the essential information such as video dimension or
           audio sample rate must be present.

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

   Generic options
       These options are shared amongst the ff* tools.

       -L  Show license.

       -h, -?, -help, --help [arg]
           Show help. An optional parameter may be specified to print help
           about a specific item. If no argument is specified, only basic (non
           advanced) tool options are shown.

           Possible values of arg are:

           long
               Print advanced tool options in addition to the basic tool
               options.

           full
               Print complete list of options, including shared and private
               options for encoders, decoders, demuxers, muxers, filters, etc.

           decoder=decoder_name
               Print detailed information about the decoder named
               decoder_name. Use the -decoders option to get a list of all
               decoders.

           encoder=encoder_name
               Print detailed information about the encoder named
               encoder_name. Use the -encoders option to get a list of all
               encoders.

           demuxer=demuxer_name
               Print detailed information about the demuxer named
               demuxer_name. Use the -formats option to get a list of all
               demuxers and muxers.

           muxer=muxer_name
               Print detailed information about the muxer named muxer_name.
               Use the -formats option to get a list of all muxers and
               demuxers.

           filter=filter_name
               Print detailed information about the filter named filter_name.
               Use the -filters option to get a list of all filters.

           bsf=bitstream_filter_name
               Print detailed information about the bitstream filter named
               bitstream_filter_name.  Use the -bsfs option to get a list of
               all bitstream filters.

           protocol=protocol_name
               Print detailed information about the protocol named
               protocol_name.  Use the -protocols option to get a list of all
               protocols.

       -version
           Show version.

       -buildconf
           Show the build configuration, one option per line.

       -formats
           Show available formats (including devices).

       -demuxers
           Show available demuxers.

       -muxers
           Show available muxers.

       -devices
           Show available devices.

       -codecs
           Show all codecs known to libavcodec.

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

       -decoders
           Show available decoders.

       -encoders
           Show all available encoders.

       -bsfs
           Show available bitstream filters.

       -protocols
           Show available protocols.

       -filters
           Show available libavfilter filters.

       -pix_fmts
           Show available pixel formats.

       -sample_fmts
           Show available sample formats.

       -layouts
           Show channel names and standard channel layouts.

       -colors
           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=192.168.0.4

       -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=192.168.0.4

       -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:

           repeat
               Indicates that repeated log output should not be compressed to
               the first line and the "Last message repeated n times" line
               will be omitted.

           level
               Indicates that log output should add a "[level]" prefix to each
               message line. This can be used as an alternative to log
               coloring, e.g. when dumping the log to file.

           Flags can also be used alone by adding a '+'/'-' prefix to
           set/reset a single flag without affecting other flags or changing
           loglevel. When setting both flags and loglevel, a '+' separator is
           expected between 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 as an assertion failure. This is not currently used for
               anything.

           fatal, 8
               Only show fatal errors. These are errors after which the
               process absolutely cannot continue.

           error, 16
               Show all errors, including ones which can be recovered from.

           warning, 24
               Show all warnings and errors. Any message related to possibly
               incorrect or unexpected events will be shown.

           info, 32
               Show informative messages during processing. This is in
               addition to warnings 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 set loglevel to "verbose":

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

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

                   ffmpeg [...] -loglevel +repeat

           By default the program logs to stderr. If coloring is supported by
           the terminal, colors are used to mark errors and warnings. Log
           coloring can be disabled setting the environment variable
           AV_LOG_FORCE_NOCOLOR, or can be forced setting the environment
           variable AV_LOG_FORCE_COLOR.

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

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

           The following options are recognized:

           file
               set the file name to use for the report; %p is expanded to the
               name of the program, %t is expanded to a timestamp, "%%" is
               expanded to a plain "%"

           level
               set the log verbosity level using a numerical value (see
               "-loglevel").

           For example, to output a report to a file named ffreport.log using
           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
           not appear in the report.

       -hide_banner
           Suppress printing banner.

           All FFmpeg tools will normally show a copyright notice, build
           options and library versions. This option can be used to suppress
           printing this information.

       -cpuflags flags (global)
           Allows setting and clearing cpu flags. This option is intended for
           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:

           x86
               mmx
               mmxext
               sse
               sse2
               sse2slow
               sse3
               sse3slow
               ssse3
               atom
               sse4.1
               sse4.2
               avx
               avx2
               xop
               fma3
               fma4
               3dnow
               3dnowext
               bmi1
               bmi2
               cmov
           ARM
               armv5te
               armv6
               armv6t2
               vfp
               vfpv3
               neon
               setend
           AArch64
               armv8
               vfp
               neon
           PowerPC
               altivec
           Specific Processors
               pentium2
               pentium3
               pentium4
               k6
               k62
               athlon
               athlonxp
               k8
       -max_alloc bytes
           Set the maximum size limit for allocating a block on the heap by
           ffmpeg's family of malloc functions. Exercise extreme caution when
           using this option. Don't use if you do not understand the full
           consequence of doing so.  Default is INT_MAX.

   AVOptions
       These options are provided directly by the libavformat, libavdevice and
       libavcodec libraries. To see the list of available AVOptions, use the
       -help option. They are separated into two categories:

       generic
           These options can be set for any container, codec or device.
           Generic options are listed under AVFormatContext options for
           containers/devices and under AVCodecContext options for codecs.

       private
           These options are specific to the given container, device or codec.
           Private options are listed under their corresponding
           containers/devices/codecs.

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

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

       All codec AVOptions are per-stream, and thus a stream specifier should
       be attached to them:

               ffmpeg -i multichannel.mxf -map 0:v:0 -map 0:a:0 -map 0:a:0 -c:a:0 ac3 -b:a:0 640k -ac:a:1 2 -c:a:1 aac -b:2 128k out.mp4

       In the above example, a multichannel audio stream is mapped twice for
       output.  The first instance is encoded with codec ac3 and bitrate 640k.
       The second instance is downmixed to 2 channels and encoded with codec
       aac. A bitrate of 128k is specified for it using absolute index of the
       output stream.

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

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

   Main options
       -f fmt (input/output)
           Force input or output file format. The format is normally auto
           detected for input files and guessed from the file extension for
           output files, so this option is not needed 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 specified
           output 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 used before an input file) for one or more streams. codec is
           the name of a decoder/encoder or a special value "copy" (output
           only) to indicate that the 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 with libx264, 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 of
           data read from the input file.

           When used as an output option (before an output url), stop writing
           the output 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 written after the limit is exceeded. The size of the
           output file is slightly more than the requested file size.

       -ss position (input/output)
           When used as an input option (before "-i"), seeks in this input
           file to position. 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), this extra segment between the seek point and position
           will be decoded and discarded. When doing stream copy or when
           -noaccurate_seek is used, it will be preserved.

           When used as an output option (before an output url), decodes but
           discards input 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
           negative values 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.
           Specifying a positive offset means that the corresponding streams
           are delayed by the time duration specified in offset.

       -itsscale scale (input,per-stream)
           Rescale input timestamps. scale should be a floating point number.

       -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 metadata on
           streams, chapters or programs. See "-map_metadata" documentation
           for details.

           This option overrides metadata set with "-map_metadata". It is also
           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 also possible to delete the disposition by setting it to 0.

           The following dispositions are recognized:

           default
           dub
           original
           comment
           lyrics
           karaoke
           forced
           hearing_impaired
           visual_impaired
           clean_effects
           attached_pic
           captions
           descriptions
           dependent
           metadata

           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 default disposition 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 specified stream(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 know
           they do not conflict with the standard, as in:

                   ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg

           The parameters set for each target are as follows.

           VCD

                   <pal>:
                   -f vcd -muxrate 1411200 -muxpreload 0.44 -packetsize 2324
                   -s 352x288 -r 25
                   -codec:v mpeg1video -g 15 -b:v 1150k -maxrate:v 1150v -minrate:v 1150k -bufsize:v 327680
                   -ar 44100 -ac 2
                   -codec:a mp2 -b:a 224k

                   <ntsc>:
                   -f vcd -muxrate 1411200 -muxpreload 0.44 -packetsize 2324
                   -s 352x240 -r 30000/1001
                   -codec:v mpeg1video -g 18 -b:v 1150k -maxrate:v 1150v -minrate:v 1150k -bufsize:v 327680
                   -ar 44100 -ac 2
                   -codec:a mp2 -b:a 224k

                   <film>:
                   -f vcd -muxrate 1411200 -muxpreload 0.44 -packetsize 2324
                   -s 352x240 -r 24000/1001
                   -codec:v mpeg1video -g 18 -b:v 1150k -maxrate:v 1150v -minrate:v 1150k -bufsize:v 327680
                   -ar 44100 -ac 2
                   -codec:a mp2 -b:a 224k

           SVCD

                   <pal>:
                   -f svcd -packetsize 2324
                   -s 480x576 -pix_fmt yuv420p -r 25
                   -codec:v mpeg2video -g 15 -b:v 2040k -maxrate:v 2516k -minrate:v 0 -bufsize:v 1835008 -scan_offset 1
                   -ar 44100
                   -codec:a mp2 -b:a 224k

                   <ntsc>:
                   -f svcd -packetsize 2324
                   -s 480x480 -pix_fmt yuv420p -r 30000/1001
                   -codec:v mpeg2video -g 18 -b:v 2040k -maxrate:v 2516k -minrate:v 0 -bufsize:v 1835008 -scan_offset 1
                   -ar 44100
                   -codec:a mp2 -b:a 224k

                   <film>:
                   -f svcd -packetsize 2324
                   -s 480x480 -pix_fmt yuv420p -r 24000/1001
                   -codec:v mpeg2video -g 18 -b:v 2040k -maxrate:v 2516k -minrate:v 0 -bufsize:v 1835008 -scan_offset 1
                   -ar 44100
                   -codec:a mp2 -b:a 224k

           DVD

                   <pal>:
                   -f dvd -muxrate 10080k -packetsize 2048
                   -s 720x576 -pix_fmt yuv420p -r 25
                   -codec:v mpeg2video -g 15 -b:v 6000k -maxrate:v 9000k -minrate:v 0 -bufsize:v 1835008
                   -ar 48000
                   -codec:a ac3 -b:a 448k

                   <ntsc>:
                   -f dvd -muxrate 10080k -packetsize 2048
                   -s 720x480 -pix_fmt yuv420p -r 30000/1001
                   -codec:v mpeg2video -g 18 -b:v 6000k -maxrate:v 9000k -minrate:v 0 -bufsize:v 1835008
                   -ar 48000
                   -codec:a ac3 -b:a 448k

                   <film>:
                   -f dvd -muxrate 10080k -packetsize 2048
                   -s 720x480 -pix_fmt yuv420p -r 24000/1001
                   -codec:v mpeg2video -g 18 -b:v 6000k -maxrate:v 9000k -minrate:v 0 -bufsize:v 1835008
                   -ar 48000
                   -codec:a ac3 -b:a 448k

           DV

                   <pal>:
                   -f dv
                   -s 720x576 -pix_fmt yuv420p -r 25
                   -ar 48000 -ac 2

                   <ntsc>:
                   -f dv
                   -s 720x480 -pix_fmt yuv411p -r 30000/1001
                   -ar 48000 -ac 2

                   <film>:
                   -f dv
                   -s 720x480 -pix_fmt yuv411p -r 24000/1001
                   -ar 48000 -ac 2

           The "dv50" target is identical to the "dv" target except that the
           pixel format set is "yuv422p" for all three standards.

           Any user-set value for a parameter above will override the target
           preset value. In that case, the output may not comply with the
           target standard.

       -dn (input/output)
           As an input option, blocks all data streams of a file from being
           filtered or being automatically selected or mapped for any output.
           See "-discard" option to disable streams individually.

           As an output option, disables data recording i.e. automatic
           selection or mapping of any data stream. 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 is codec-
           dependent.  If qscale is used without a stream_specifier then it
           applies only to the video stream, this is to maintain compatibility
           with previous behavior and as specifying the same codec specific
           value to 2 different codecs that is audio and video generally is
           not what is intended when no stream_specifier is used.

       -filter[:stream_specifier] filtergraph (output,per-stream)
           Create the filtergraph specified by filtergraph and use it to
           filter the stream.

           filtergraph is a description of the filtergraph to apply to the
           stream, and must have a single input and a single output of the
           same type of the stream. In the filtergraph, the input is
           associated to the label "in", and the output to the label "out".
           See the ffmpeg-filters manual for more information about the
           filtergraph syntax.

           See the -filter_complex option if you want 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 its
           argument is the name of the file from which a filtergraph
           description is to be read.

       -filter_threads nb_threads (global)
           Defines how many threads are used to process a filter pipeline.
           Each pipeline will 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
           explicitly disable it you need to specify "-nostats".

       -stats_period time (global)
           Set period at which encoding progress/statistics are updated.
           Default is 0.5 seconds.

       -progress url (global)
           Send program-friendly progress information to url.

           Progress information is written periodically and at the end of the
           encoding process. It is made of "key=value" lines. key consists of
           only alphanumeric characters. The last key of a sequence of
           progress information is always "progress".

           The update period is set using "-stats_period".

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

           Disabling interaction on standard input is useful, for example, if
           ffmpeg is in the background process group. Roughly the same result
           can be achieved with "ffmpeg ... < /dev/null" but it requires a
           shell.

       -debug_ts (global)
           Print timestamp information. It is off by default. This option is
           mostly useful for testing and debugging purposes, and the output
           format may change from one version to another, so it should not be
           employed 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
           formats like Matroska for e.g. fonts used in rendering subtitles.
           Attachments are implemented as a specific type of stream, so this
           option will add a new stream to the file. It is then possible to
           use per-stream options on this stream in the usual way. Attachment
           streams created with this option will be created after all the
           other streams (i.e. those created with "-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.
           If filename is empty, then the value of the "filename" metadata tag
           will 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 this option can actually be used to extract extradata from any
           stream, not just attachments.

   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
           instead generate timestamps assuming constant frame rate fps.  This
           is not the same as the -framerate option used for some input
           formats like 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 output frame rate fps.

       -fpsmax[:stream_specifier] fps (output,per-stream)
           Set maximum frame rate (Hz value, fraction or abbreviation).

           Clamps output frame rate when output framerate is auto-set and is
           higher than this value.  Useful in batch processing or when input
           framerate is wrongly detected as very high.  It cannot be set
           together with "-r". It is ignored during streamcopy.

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

           As an input option, this is a shortcut for the video_size private
           option, recognized by some demuxers for which the frame size is
           either not stored in the file or is configurable -- e.g. raw video
           or video grabbers.

           As an output option, this inserts the "scale" video filter to the
           end of the corresponding filtergraph. Please use the "scale" filter
           directly 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 the
           form num:den, where num and den are the numerator 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 ratio
           stored at container level, but not the aspect ratio stored in
           encoded frames, if it exists.

       -vn (input/output)
           As an input option, blocks all video streams of a file from being
           filtered or being automatically selected or mapped for any output.
           See "-discard" option to disable streams individually.

           As an output option, disables video recording i.e. automatic
           selection or mapping of any video stream. 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-pass video
           encoding. The statistics of the video are recorded in the first
           pass into a log file (see also the option -passlogfile), and in the
           second pass that log file is used to generate the video at the
           exact requested bitrate.  On pass 1, you may just deactivate audio
           and set output to null, examples for Windows and Unix:

                   ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
                   ffmpeg -i foo.mov -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 name
           prefix is ``ffmpeg2pass''. The complete file name will be
           PREFIX-N.log, where N is a number specific to the output stream

       -vf filtergraph (output)
           Create the filtergraph specified by filtergraph and use it to
           filter the stream.

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

       -autorotate
           Automatically rotate the video according to file metadata. Enabled
           by default, use -noautorotate to disable it.

       -autoscale
           Automatically scale the video according to the resolution of first
           frame.  Enabled by default, use -noautoscale to disable it. When
           autoscale is disabled, all output frames of filter graph might not
           be in the same resolution and may be inadequate for some
           encoder/muxer. Therefore, it is not recommended to disable it
           unless you really know what you are doing.  Disable autoscale at
           your own risk.

   Advanced Video options
       -pix_fmt[:stream_specifier] format (input/output,per-stream)
           Set pixel format. Use "-pix_fmts" to show all the supported pixel
           formats.  If the selected pixel format can not be selected, ffmpeg
           will print a warning and select the best pixel format supported by
           the encoder.  If pix_fmt is prefixed by a "+", ffmpeg will exit
           with an error if the requested pixel format can not be selected,
           and automatic conversions inside filtergraphs are disabled.  If
           pix_fmt is a single "+", ffmpeg selects the same pixel format as
           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 and end frame numbers, last one is quantizer to use if
           positive, or quality factor if negative.

       -ilme
           Force interlacing support in encoder (MPEG-2 and MPEG-4 only).  Use
           this option if your input file is interlaced and you want to keep
           the interlaced format for minimum losses.  The alternative is to
           deinterlace the input stream by use of a filter such as "yadif" or
           "bwdif", but deinterlacing introduces losses.

       -psnr
           Calculate PSNR of compressed frames.

       -vstats
           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
           Intra_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[:stream_specifier] source (output,per-stream)
           force_key_frames can take arguments of the following form:

           time[,time...]
               If the argument consists of timestamps, ffmpeg will round the
               specified times to the nearest output timestamp as per the
               encoder time base and force a keyframe at the first frame
               having timestamp equal or greater than the computed timestamp.
               Note that if the encoder time base is too coarse, then the
               keyframes may be forced on frames with timestamps lower than
               the specified time.  The default encoder time base is the
               inverse of the output framerate but may be set otherwise via
               "-enc_time_base".

               If one of the times is ""chapters"[delta]", it is expanded into
               the time of the beginning of all chapters in the file, shifted
               by delta, expressed as a time in seconds.  This option can be
               useful to ensure that a seek point is present at a chapter 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 second before the beginning of every chapter:

                       -force_key_frames 0:05:00,chapters-0.1

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

               The expression in expr can contain the following constants:

               n   the number of current processed frame, starting from 0

               n_forced
                   the number of forced frames

               prev_forced_n
                   the number of the previous forced frame, it is "NAN" when
                   no keyframe was forced yet

               prev_forced_t
                   the time of the previous forced frame, it is "NAN" when no
                   keyframe was forced yet

               t   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))

           source
               If the argument is "source", ffmpeg will force a key frame if
               the current frame being encoded is marked as a key frame in its
               source.

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

       -copyinkf[:stream_specifier] (output,per-stream)
           When doing stream copy, copy also non-key frames found at the
           beginning.

       -init_hw_device type[=name][:device[,key=value...]]
           Initialise a new hardware device of type type called name, using
           the given 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 the
           device type:

           cuda
               device is the number of the CUDA device.

           dxva2
               device is the number of the Direct3D 9 display adapter.

           vaapi
               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).

           vdpau
               device is an X11 display name.  If not specified, it will
               attempt to open the default X11 display ($DISPLAY).

           qsv device selects a value in MFX_IMPL_*. Allowed values are:

               auto
               sw
               hw
               auto_any
               hw_any
               hw2
               hw3
               hw4

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

           opencl
               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 only devices matching particular platform or
               device strings.

               The strings usable as filters are:

               platform_profile
               platform_version
               platform_name
               platform_vendor
               platform_extensions
               device_name
               device_vendor
               driver_version
               device_version
               device_profile
               device_extensions
               device_type

               The indices and filters must together uniquely select a device.

               Examples:

               -init_hw_device opencl:0.1
                   Choose the second device on the first platform.

               -init_hw_device opencl:,device_name=Foo9000
                   Choose the device with a name containing the string
                   Foo9000.

               -init_hw_device
               opencl:1,device_type=gpu,device_extensions=cl_khr_fp16
                   Choose the GPU device on the second platform supporting the
                   cl_khr_fp16 extension.

           vulkan
               If device is an integer, it selects the device by its index in
               a system-dependent list of devices.  If device is any other
               string, it selects the first device with a name containing that
               string as a substring.

               The following options are recognized:

               debug
                   If set to 1, enables the validation layer, if installed.

               linear_images
                   If set to 1, images allocated by the hwcontext will be
                   linear and locally mappable.

               instance_extensions
                   A plus separated list of additional instance extensions to
                   enable.

               device_extensions
                   A plus separated list of additional device extensions to
                   enable.

               Examples:

               -init_hw_device vulkan:1
                   Choose the second device on the system.

               -init_hw_device vulkan:RADV
                   Choose the first device with a name containing the string
                   RADV.

               -init_hw_device
               vulkan:0,instance_extensions=VK_KHR_wayland_surface+VK_KHR_xcb_surface
                   Choose the first device and enable the Wayland and XCB
                   instance extensions.

       -init_hw_device type[=name]@source
           Initialise a new hardware device of type type called name, deriving
           it from the existing device with the name source.

       -init_hw_device list
           List all hardware device types supported in this build of ffmpeg.

       -filter_hw_device name
           Pass the hardware device called name to all filters in any filter
           graph.  This can be used to set the device to upload to with the
           "hwupload" filter, or the device to map to with the "hwmap" filter.
           Other filters may also make use of this parameter when they require
           a hardware device.  Note that this is typically only required when
           the input is not already in hardware frames - when it is, filters
           will derive the device they require from the context of the frames
           they receive as input.

           This is a global setting, so all filters will receive the same
           device.

       -hwaccel[:stream_specifier] hwaccel (input,per-stream)
           Use hardware acceleration to decode the matching stream(s). The
           allowed values of hwaccel are:

           none
               Do not use any hardware acceleration (the default).

           auto
               Automatically select the hardware acceleration method.

           vdpau
               Use VDPAU (Video Decode and Presentation API for Unix) hardware
               acceleration.

           dxva2
               Use DXVA2 (DirectX Video Acceleration) hardware acceleration.

           vaapi
               Use VAAPI (Video Acceleration API) hardware acceleration.

           qsv Use the Intel QuickSync Video acceleration for video
               transcoding.

               Unlike most other values, this option does not enable
               accelerated decoding (that is used automatically whenever a qsv
               decoder is selected), but accelerated transcoding, without
               copying the frames into the system memory.

               For it to work, both the decoder and the encoder must support
               QSV acceleration and no filters must be used.

           This option has no effect if the selected hwaccel is not available
           or not supported by the chosen decoder.

           Note that most acceleration methods are intended for playback and
           will not be faster than software decoding on modern CPUs.
           Additionally, ffmpeg will usually need to copy the decoded frames
           from the GPU memory into the system memory, resulting in further
           performance loss. This option is thus mainly useful for testing.

       -hwaccel_device[:stream_specifier] hwaccel_device (input,per-stream)
           Select a device to use for hardware acceleration.

           This option only makes sense when the -hwaccel option is also
           specified.  It can either refer to an existing device created with
           -init_hw_device by name, or it can create a new device as if
           -init_hw_device type:hwaccel_device were called immediately before.

       -hwaccels
           List all hardware acceleration methods supported in this build of
           ffmpeg.

   Audio Options
       -aframes number (output)
           Set the number of audio frames to output. This is an obsolete alias
           for "-frames:a", which you should use instead.

       -ar[:stream_specifier] freq (input/output,per-stream)
           Set the audio sampling frequency. For output streams it is set by
           default to the frequency of the corresponding input stream. For
           input streams this option only makes sense for audio grabbing
           devices and raw demuxers and is mapped to the corresponding demuxer
           options.

       -aq q (output)
           Set the audio quality (codec-specific, VBR). This is an alias for
           -q:a.

       -ac[:stream_specifier] channels (input/output,per-stream)
           Set the number of audio channels. For output streams it is set by
           default to the number of input audio channels. For input streams
           this option only makes sense for audio grabbing devices and raw
           demuxers and is mapped to the corresponding demuxer options.

       -an (input/output)
           As an input option, blocks all audio streams of a file from being
           filtered or being automatically selected or mapped for any output.
           See "-discard" option to disable streams individually.

           As an output option, disables audio recording i.e. automatic
           selection or mapping of any audio stream. For full manual control
           see the "-map" option.

       -acodec codec (input/output)
           Set the audio codec. This is an alias for "-codec:a".

       -sample_fmt[:stream_specifier] sample_fmt (output,per-stream)
           Set the audio sample format. Use "-sample_fmts" to get a list of
           supported sample formats.

       -af filtergraph (output)
           Create the filtergraph specified by filtergraph and use it to
           filter the stream.

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

   Advanced Audio options
       -atag fourcc/tag (output)
           Force audio tag/fourcc. This is an alias for "-tag:a".

       -absf bitstream_filter
           Deprecated, see -bsf

       -guess_layout_max channels (input,per-stream)
           If some input channel layout is not known, try to guess only if it
           corresponds to at most the specified number of channels. For
           example, 2 tells to ffmpeg to recognize 1 channel as mono and 2
           channels as stereo but not 6 channels as 5.1. The default is to
           always try to guess. Use 0 to disable all guessing.

   Subtitle options
       -scodec codec (input/output)
           Set the subtitle codec. This is an alias for "-codec:s".

       -sn (input/output)
           As an input option, blocks all subtitle streams of a file from
           being filtered or being automatically selected or mapped for any
           output. See "-discard" option to disable streams individually.

           As an output option, disables subtitle recording i.e. automatic
           selection or mapping of any subtitle stream. For full manual
           control see the "-map" option.

       -sbsf bitstream_filter
           Deprecated, see -bsf

   Advanced Subtitle options
       -fix_sub_duration
           Fix subtitles durations. For each subtitle, wait for the next
           packet in the same stream and adjust the duration of the first to
           avoid overlap. This is necessary with some subtitles codecs,
           especially DVB subtitles, because the duration in the original
           packet is only a rough estimate and the end is actually marked by
           an empty subtitle frame. Failing to use this option when necessary
           can result in exaggerated durations or muxing failures due to non-
           monotonic timestamps.

           Note that this option will delay the output of all data until the
           next subtitle packet is decoded: it may increase memory consumption
           and latency a lot.

       -canvas_size size
           Set the size of the canvas used to render subtitles.

   Advanced options
       -map
       [-]input_file_id[:stream_specifier][?][,sync_file_id[:stream_specifier]]
       | [linklabel] (output)
           Designate one or more input streams as a source for the output
           file. Each input stream is identified by the input file index
           input_file_id and the input stream index input_stream_id within the
           input file. Both indices start at 0. If specified,
           sync_file_id:stream_specifier sets which input stream is used as a
           presentation sync reference.

           The first "-map" option on the command line specifies the source
           for output stream 0, the second "-map" option specifies the source
           for output stream 1, etc.

           A "-" character before the stream identifier creates a "negative"
           mapping.  It disables matching streams from already created
           mappings.

           A trailing "?" after the stream index will allow the map to be
           optional: if the map matches no streams the map will be ignored
           instead of failing. Note the map will still fail if an invalid
           input file index is used; such as if the map refers to a non-
           existent input.

           An alternative [linklabel] form will map outputs from complex
           filter graphs (see the -filter_complex option) to the output file.
           linklabel must correspond to a defined output link label in the
           graph.

           For example, to map ALL streams from the first input file to output

                   ffmpeg -i INPUT -map 0 output

           For example, if you have two audio streams in the first input file,
           these streams are identified by "0:0" and "0:1". You can use "-map"
           to select which streams to place in an output file. For example:

                   ffmpeg -i INPUT -map 0:1 out.wav

           will map the input stream in INPUT identified by "0:1" to the
           (single) output stream in out.wav.

           For example, to select the stream with index 2 from input file
           a.mov (specified by the identifier "0:2"), and stream with index 6
           from input b.mov (specified by the identifier "1:6"), and copy them
           to the output file out.mov:

                   ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov

           To select all video and the third audio stream from an input file:

                   ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT

           To map all the streams except the second audio, use negative
           mappings

                   ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT

           To map the video and audio streams from the first input, and using
           the trailing "?", ignore the audio mapping if no audio streams
           exist in the first input:

                   ffmpeg -i INPUT -map 0:v -map 0:a? OUTPUT

           To pick the English audio stream:

                   ffmpeg -i INPUT -map 0:m:language:eng OUTPUT

           Note that using this option disables the default mappings for this
           output file.

       -ignore_unknown
           Ignore input streams with unknown type instead of failing if
           copying such streams is attempted.

       -copy_unknown
           Allow input streams with unknown type to be copied instead of
           failing if copying such streams is attempted.

       -map_channel
       [input_file_id.stream_specifier.channel_id|-1][?][:output_file_id.stream_specifier]
           Map an audio channel from a given input to an output. If
           output_file_id.stream_specifier is not set, the audio channel will
           be mapped on all the audio streams.

           Using "-1" instead of input_file_id.stream_specifier.channel_id
           will map a muted channel.

           A trailing "?" will allow the map_channel to be optional: if the
           map_channel matches no channel the map_channel will be ignored
           instead of failing.

           For example, assuming INPUT is a stereo audio file, you can switch
           the two audio channels with the following command:

                   ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT

           If you want to mute the first channel and keep the second:

                   ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT

           The order of the "-map_channel" option specifies the order of the
           channels in the output stream. The output channel layout is guessed
           from the number of channels mapped (mono if one "-map_channel",
           stereo if two, etc.). Using "-ac" in combination of "-map_channel"
           makes the channel gain levels to be updated if input and output
           channel layouts don't match (for instance two "-map_channel"
           options and "-ac 6").

           You can also extract each channel of an input to specific outputs;
           the following command extracts two channels of the INPUT audio
           stream (file 0, stream 0) to the respective OUTPUT_CH0 and
           OUTPUT_CH1 outputs:

                   ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1

           The following example splits the channels of a stereo input into
           two separate streams, which are put into the same output file:

                   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

           Note that currently each output stream can only contain channels
           from a single input stream; you can't for example use
           "-map_channel" to pick multiple input audio channels contained in
           different streams (from the same or different files) and merge them
           into a single output stream. It is therefore not currently
           possible, for example, to turn two separate mono streams into a
           single stereo stream. However splitting a stereo stream into two
           single channel mono streams is possible.

           If you need this feature, a possible workaround is to use the
           amerge filter. For example, if you need to merge a media (here
           input.mkv) with 2 mono audio streams into one single stereo channel
           audio stream (and keep the video stream), you can use the following
           command:

                   ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv

           To map the first two audio channels from the first input, and using
           the trailing "?", ignore the audio channel mapping if the first
           input is mono instead of stereo:

                   ffmpeg -i INPUT -map_channel 0.0.0 -map_channel 0.0.1? OUTPUT

       -map_metadata[:metadata_spec_out] infile[:metadata_spec_in]
       (output,per-metadata)
           Set metadata information of the next output file from infile. Note
           that those are file indices (zero-based), not filenames.  Optional
           metadata_spec_in/out parameters specify, which metadata to copy.  A
           metadata specifier can have the following forms:

           g   global metadata, i.e. metadata that applies to the whole file

           s[:stream_spec]
               per-stream metadata. stream_spec is a stream specifier as
               described in the Stream specifiers chapter. In an input
               metadata specifier, the first matching stream is copied from.
               In an output metadata specifier, all matching streams are
               copied to.

           c:chapter_index
               per-chapter metadata. chapter_index is the zero-based chapter
               index.

           p:program_index
               per-program metadata. program_index is the zero-based program
               index.

           If metadata specifier is omitted, it defaults to global.

           By default, global metadata is copied from the first input file,
           per-stream and per-chapter metadata is copied along with
           streams/chapters. These default mappings are disabled by creating
           any mapping of the relevant type. A negative file index can be used
           to create a dummy mapping that just disables automatic copying.

           For example to copy metadata from the first stream of the input
           file to global metadata of the output file:

                   ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3

           To do the reverse, i.e. copy global metadata to all audio streams:

                   ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv

           Note that simple 0 would work as well in this example, since global
           metadata is assumed by default.

       -map_chapters input_file_index (output)
           Copy chapters from input file with index input_file_index to the
           next output file. If no chapter mapping is specified, then chapters
           are copied from the first input file with at least one chapter. Use
           a negative file index to disable any chapter copying.

       -benchmark (global)
           Show benchmarking information at the end of an encode.  Shows real,
           system and user time used and maximum memory consumption.  Maximum
           memory consumption is not supported on all systems, it will usually
           display as 0 if not supported.

       -benchmark_all (global)
           Show benchmarking information during the encode.  Shows real,
           system and user time used in various steps (audio/video
           encode/decode).

       -timelimit duration (global)
           Exit after ffmpeg has been running for duration seconds in CPU user
           time.

       -dump (global)
           Dump each input packet to stderr.

       -hex (global)
           When dumping packets, also dump the payload.

       -re (input)
           Read input at native frame rate. Mainly used to simulate a grab
           device, or live input stream (e.g. when reading from a file).
           Should not be used with actual grab devices or live input streams
           (where it can cause packet loss).  By default ffmpeg attempts to
           read the input(s) as fast as possible.  This option will slow down
           the reading of the input(s) to the native frame rate of the
           input(s). It is useful for real-time output (e.g. live streaming).

       -vsync parameter
           Video sync method.  For compatibility reasons old values can be
           specified as numbers.  Newly added values will have to be specified
           as strings always.

           0, passthrough
               Each frame is passed with its timestamp from the demuxer to the
               muxer.

           1, cfr
               Frames will be duplicated and dropped to achieve exactly the
               requested constant frame rate.

           2, vfr
               Frames are passed through with their timestamp or dropped so as
               to prevent 2 frames from having the same timestamp.

           drop
               As passthrough but destroys all timestamps, making the muxer
               generate fresh timestamps based on frame-rate.

           -1, auto
               Chooses between 1 and 2 depending on muxer capabilities. This
               is the default method.

           Note that the timestamps may be further modified by the muxer,
           after this.  For example, in the case that the format option
           avoid_negative_ts is enabled.

           With -map you can select from which stream the timestamps should be
           taken. You can leave either video or audio unchanged and sync the
           remaining stream(s) to the unchanged one.

       -frame_drop_threshold parameter
           Frame drop threshold, which specifies how much behind video frames
           can be before they are dropped. In frame rate units, so 1.0 is one
           frame.  The default is -1.1. One possible usecase is to avoid
           framedrops in case of noisy timestamps or to increase frame drop
           precision in case of exact timestamps.

       -async samples_per_second
           Audio sync method. "Stretches/squeezes" the audio stream to match
           the timestamps, the parameter is the maximum samples per second by
           which the audio is changed.  -async 1 is a special case where only
           the start of the audio stream is corrected without any later
           correction.

           Note that the timestamps may be further modified by the muxer,
           after this.  For example, in the case that the format option
           avoid_negative_ts is enabled.

           This option has been deprecated. Use the "aresample" audio filter
           instead.

       -adrift_threshold time
           Set the minimum difference between timestamps and audio data (in
           seconds) to trigger adding/dropping samples to make it match the
           timestamps. This option effectively is a threshold to select
           between hard (add/drop) and soft (squeeze/stretch) compensation.
           "-async" must be set to a positive value.

       -apad parameters (output,per-stream)
           Pad the output audio stream(s). This is the same as applying "-af
           apad".  Argument is a string of filter parameters composed the same
           as with the "apad" filter.  "-shortest" must be set for this output
           for the option to take effect.

       -copyts
           Do not process input timestamps, but keep their values without
           trying to sanitize them. In particular, do not remove the initial
           start time offset value.

           Note that, depending on the vsync option or on specific muxer
           processing (e.g. in case the format option avoid_negative_ts is
           enabled) the output timestamps may mismatch with the input
           timestamps even when this option is selected.

       -start_at_zero
           When used with copyts, shift input timestamps so they start at
           zero.

           This means that using e.g. "-ss 50" will make output timestamps
           start at 50 seconds, regardless of what timestamp the input file
           started at.

       -copytb mode
           Specify how to set the encoder timebase when stream copying.  mode
           is an integer numeric value, and can assume one of the following
           values:

           1   Use the demuxer timebase.

               The time base is copied to the output encoder from the
               corresponding input demuxer. This is sometimes required to
               avoid non monotonically increasing timestamps when copying
               video streams with variable frame rate.

           0   Use the decoder timebase.

               The time base is copied to the output encoder from the
               corresponding input decoder.

           -1  Try to make the choice automatically, in order to generate a
               sane output.

           Default value is -1.

       -enc_time_base[:stream_specifier] timebase (output,per-stream)
           Set the encoder timebase. timebase is a floating point number, and
           can assume one of the following values:

           0   Assign a default value according to the media type.

               For video - use 1/framerate, for audio - use 1/samplerate.

           -1  Use the input stream timebase when possible.

               If an input stream is not available, the default timebase will
               be used.

           >0  Use the provided number as the timebase.

               This field can be provided as a ratio of two integers (e.g.
               1:24, 1:48000) or as a floating point number (e.g. 0.04166,
               2.0833e-5)

           Default value is 0.

       -bitexact (input/output)
           Enable bitexact mode for (de)muxer and (de/en)coder

       -shortest (output)
           Finish encoding when the shortest input stream ends.

       -dts_delta_threshold
           Timestamp discontinuity delta threshold.

       -dts_error_threshold seconds
           Timestamp error delta threshold. This threshold use to discard
           crazy/damaged timestamps and the default is 30 hours which is
           arbitrarily picked and quite conservative.

       -muxdelay seconds (output)
           Set the maximum demux-decode delay.

       -muxpreload seconds (output)
           Set the initial demux-decode delay.

       -streamid output-stream-index:new-value (output)
           Assign a new stream-id value to an output stream. This option
           should be specified prior to the output filename to which it
           applies.  For the situation where multiple output files exist, a
           streamid may be reassigned to a different value.

           For example, to set the stream 0 PID to 33 and the stream 1 PID to
           36 for an output mpegts file:

                   ffmpeg -i inurl -streamid 0:33 -streamid 1:36 out.ts

       -bsf[:stream_specifier] bitstream_filters (output,per-stream)
           Set bitstream filters for matching streams. bitstream_filters is a
           comma-separated list of bitstream filters. Use the "-bsfs" option
           to get the list of bitstream filters.

                   ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264


                   ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt

       -tag[:stream_specifier] codec_tag (input/output,per-stream)
           Force a tag/fourcc for matching streams.

       -timecode hh:mm:ssSEPff
           Specify Timecode for writing. SEP is ':' for non drop timecode and
           ';' (or '.') for drop.

                   ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg

       -filter_complex filtergraph (global)
           Define a complex filtergraph, i.e. one with arbitrary number of
           inputs and/or outputs. For simple graphs -- those with one input
           and one output of the same type -- see the -filter options.
           filtergraph is a description of the filtergraph, as described in
           the ``Filtergraph syntax'' section of the ffmpeg-filters manual.

           Input link labels must refer to input streams using the
           "[file_index:stream_specifier]" syntax (i.e. the same as -map
           uses). If stream_specifier matches multiple streams, the first one
           will be used. An unlabeled input will be connected to the first
           unused input stream of the matching type.

           Output link labels are referred to with -map. Unlabeled outputs are
           added to the first output file.

           Note that with this option it is possible to use only lavfi sources
           without normal input files.

           For example, to overlay an image over video

                   ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
                   '[out]' out.mkv

           Here "[0:v]" refers to the first video stream in the first input
           file, which is linked to the first (main) input of the overlay
           filter. Similarly the first video stream in the second input is
           linked to the second (overlay) input of overlay.

           Assuming there is only one video stream in each input file, we can
           omit input labels, so the above is equivalent to

                   ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map
                   '[out]' out.mkv

           Furthermore we can omit the output label and the single output from
           the filter graph will be added to the output file automatically, so
           we can simply write

                   ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv

           As a special exception, you can use a bitmap subtitle stream as
           input: it will be converted into a video with the same size as the
           largest video in the file, or 720x576 if no video is present. Note
           that this is an experimental and temporary solution. It will be
           removed once libavfilter has proper support for subtitles.

           For example, to hardcode subtitles on top of a DVB-T recording
           stored in MPEG-TS format, delaying the subtitles by 1 second:

                   ffmpeg -i input.ts -filter_complex \
                     '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
                     -sn -map '#0x2dc' output.mkv

           (0x2d0, 0x2dc and 0x2ef are the MPEG-TS PIDs of respectively the
           video, audio and subtitles streams; 0:0, 0:3 and 0:7 would have
           worked too)

           To generate 5 seconds of pure red video using lavfi "color" source:

                   ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv

       -filter_complex_threads nb_threads (global)
           Defines how many threads are used to process a filter_complex
           graph.  Similar to filter_threads but used for "-filter_complex"
           graphs only.  The default is the number of available CPUs.

       -lavfi filtergraph (global)
           Define a complex filtergraph, i.e. one with arbitrary number of
           inputs and/or outputs. Equivalent to -filter_complex.

       -filter_complex_script filename (global)
           This option is similar to -filter_complex, the only difference is
           that its argument is the name of the file from which a complex
           filtergraph description is to be read.

       -accurate_seek (input)
           This option enables or disables accurate seeking in input files
           with the -ss option. It is enabled by default, so seeking is
           accurate when transcoding. Use -noaccurate_seek to disable it,
           which may be useful e.g. when copying some streams and transcoding
           the others.

       -seek_timestamp (input)
           This option enables or disables seeking by timestamp in input files
           with the -ss option. It is disabled by default. If enabled, the
           argument to the -ss option is considered an actual timestamp, and
           is not offset by the start time of the file. This matters only for
           files which do not start from timestamp 0, such as transport
           streams.

       -thread_queue_size size (input)
           This option sets the maximum number of queued packets when reading
           from the file or device. With low latency / high rate live streams,
           packets may be discarded if they are not read in a timely manner;
           setting this value can force ffmpeg to use a separate input thread
           and read packets as soon as they arrive. By default ffmpeg only do
           this if multiple inputs are specified.

       -sdp_file file (global)
           Print sdp information for an output stream to file.  This allows
           dumping sdp information when at least one output isn't an rtp
           stream. (Requires at least one of the output formats to be rtp).

       -discard (input)
           Allows discarding specific streams or frames from streams.  Any
           input stream can be fully discarded, using value "all" whereas
           selective discarding of frames from a stream occurs at the demuxer
           and is not supported by all demuxers.

           none
               Discard no frame.

           default
               Default, which discards no frames.

           noref
               Discard all non-reference frames.

           bidir
               Discard all bidirectional frames.

           nokey
               Discard all frames excepts keyframes.

           all Discard all frames.

       -abort_on flags (global)
           Stop and abort on various conditions. The following flags are
           available:

           empty_output
               No packets were passed to the muxer, the output is empty.

           empty_output_stream
               No packets were passed to the muxer in some of the output
               streams.

       -max_error_rate (global)
           Set fraction of decoding frame failures across all inputs which
           when crossed ffmpeg will return exit code 69. Crossing this
           threshold does not terminate processing. Range is a floating-point
           number between 0 to 1. Default is 2/3.

       -xerror (global)
           Stop and exit on error

       -max_muxing_queue_size packets (output,per-stream)
           When transcoding audio and/or video streams, ffmpeg will not begin
           writing into the output until it has one packet for each such
           stream. While waiting for that to happen, packets for other streams
           are buffered. This option sets the size of this buffer, in packets,
           for the matching output stream.

           The default value of this option should be high enough for most
           uses, so only touch this option if you are sure that you need it.

       -muxing_queue_data_threshold bytes (output,per-stream)
           This is a minimum threshold until which the muxing queue size is
           not taken into account. Defaults to 50 megabytes per stream, and is
           based on the overall size of packets passed to the muxer.

       -auto_conversion_filters (global)
           Enable automatically inserting format conversion filters in all
           filter graphs, including those defined by -vf, -af, -filter_complex
           and -lavfi. If filter format negotiation requires a conversion, the
           initialization of the filters will fail.  Conversions can still be
           performed by inserting the relevant conversion filter (scale,
           aresample) in the graph.  On by default, to explicitly disable it
           you need to specify "-noauto_conversion_filters".

   Preset files
       A preset file contains a sequence of option=value pairs, one for each
       line, specifying a sequence of options which would be awkward to
       specify on the command line. Lines starting with the hash ('#')
       character are ignored and are used to provide comments. Check the
       presets directory in the FFmpeg source tree for examples.

       There are two types of preset files: ffpreset and avpreset files.

       ffpreset files

       ffpreset files are specified with the "vpre", "apre", "spre", and
       "fpre" options. The "fpre" option takes the filename of the preset
       instead of a preset name as input and can be used for any kind of
       codec. For the "vpre", "apre", and "spre" options, the options
       specified in a preset file are applied to the currently selected codec
       of the same type as the preset option.

       The argument passed to the "vpre", "apre", and "spre" preset options
       identifies the preset file to use according to the following rules:

       First ffmpeg searches for a file named arg.ffpreset in the directories
       $FFMPEG_DATADIR (if set), and $HOME/.ffmpeg, and in the datadir defined
       at configuration time (usually PREFIX/share/ffmpeg) or in a ffpresets
       folder along the executable on win32, in that order. For example, if
       the argument is "libvpx-1080p", it will search for the file
       libvpx-1080p.ffpreset.

       If no such file is found, then ffmpeg will search for a file named
       codec_name-arg.ffpreset in the above-mentioned directories, where
       codec_name is the name of the codec to which the preset file options
       will be applied. For example, if you select the video codec with
       "-vcodec libvpx" and use "-vpre 1080p", then it will search for the
       file libvpx-1080p.ffpreset.

       avpreset files

       avpreset files are specified with the "pre" option. They work similar
       to ffpreset files, but they only allow encoder- specific options.
       Therefore, an option=value pair specifying an encoder cannot be used.

       When the "pre" option is specified, ffmpeg will look for files with the
       suffix .avpreset in the directories $AVCONV_DATADIR (if set), and
       $HOME/.avconv, and in the datadir defined at configuration time
       (usually PREFIX/share/ffmpeg), in that order.

       First ffmpeg searches for a file named codec_name-arg.avpreset in the
       above-mentioned directories, where codec_name is the name of the codec
       to which the preset file options will be applied. For example, if you
       select the video codec with "-vcodec libvpx" and use "-pre 1080p", then
       it will search for the file libvpx-1080p.avpreset.

       If no such file is found, then ffmpeg will search for a file named
       arg.avpreset in the same directories.


EXAMPLES

   Video and Audio grabbing
       If you specify the input format and device then ffmpeg can grab video
       and audio directly.

               ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg

       Or with an ALSA audio source (mono input, card id 1) instead of OSS:

               ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg

       Note that you must activate the right video source and channel before
       launching ffmpeg with any TV viewer such as
       <http://linux.bytesex.org/xawtv/> by Gerd Knorr. You also have to set
       the audio recording levels correctly with a standard mixer.

   X11 grabbing
       Grab the X11 display with ffmpeg via

               ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0 /tmp/out.mpg

       0.0 is display.screen number of your X11 server, same as the DISPLAY
       environment variable.

               ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0+10,20 /tmp/out.mpg

       0.0 is display.screen number of your X11 server, same as the DISPLAY
       environment variable. 10 is the x-offset and 20 the y-offset for the
       grabbing.

   Video and Audio file format conversion
       Any supported file format and protocol can serve as input to ffmpeg:

       Examples:

       o   You can use YUV files as input:

                   ffmpeg -i /tmp/test%d.Y /tmp/out.mpg

           It will use the files:

                   /tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
                   /tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...

           The Y files use twice the resolution of the U and V files. They are
           raw files, without header. They can be generated by all decent
           video decoders. You must specify the size of the image with the -s
           option if ffmpeg cannot guess it.

       o   You can input from a raw YUV420P file:

                   ffmpeg -i /tmp/test.yuv /tmp/out.avi

           test.yuv is a file containing raw YUV planar data. Each frame is
           composed of the Y plane followed by the U and V planes at half
           vertical and horizontal resolution.

       o   You can output to a raw YUV420P file:

                   ffmpeg -i mydivx.avi hugefile.yuv

       o   You can set several input files and output files:

                   ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg

           Converts the audio file a.wav and the raw YUV video file a.yuv to
           MPEG file a.mpg.

       o   You can also do audio and video conversions at the same time:

                   ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2

           Converts a.wav to MPEG audio at 22050 Hz sample rate.

       o   You can encode to several formats at the same time and define a
           mapping from input stream to output streams:

                   ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2

           Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits.
           '-map file:index' specifies which input stream is used for each
           output stream, in the order of the definition of output streams.

       o   You can transcode decrypted VOBs:

                   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

           This is a typical DVD ripping example; the input is a VOB file, the
           output an AVI file with MPEG-4 video and MP3 audio. Note that in
           this command we use B-frames so the MPEG-4 stream is DivX5
           compatible, and GOP size is 300 which means one intra frame every
           10 seconds for 29.97fps input video. Furthermore, the audio stream
           is MP3-encoded so you need to enable LAME support by passing
           "--enable-libmp3lame" to configure.  The mapping is particularly
           useful for DVD transcoding to get the desired audio language.

           NOTE: To see the supported input formats, use "ffmpeg -demuxers".

       o   You can extract images from a video, or create a video from many
           images:

           For extracting images from a video:

                   ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg

           This will extract one video frame per second from the video and
           will output them in files named foo-001.jpeg, foo-002.jpeg, etc.
           Images will be rescaled to fit the new WxH values.

           If you want to extract just a limited number of frames, you can use
           the above command in combination with the "-frames:v" or "-t"
           option, or in combination with -ss to start extracting from a
           certain point in time.

           For creating a video from many images:

                   ffmpeg -f image2 -framerate 12 -i foo-%03d.jpeg -s WxH foo.avi

           The syntax "foo-%03d.jpeg" specifies to use a decimal number
           composed of three digits padded with zeroes to express the sequence
           number. It is the same syntax supported by the C printf function,
           but only formats accepting a normal integer are suitable.

           When importing an image sequence, -i also supports expanding shell-
           like wildcard patterns (globbing) internally, by selecting the
           image2-specific "-pattern_type glob" option.

           For example, for creating a video from filenames matching the glob
           pattern "foo-*.jpeg":

                   ffmpeg -f image2 -pattern_type glob -framerate 12 -i 'foo-*.jpeg' -s WxH foo.avi

       o   You can put many streams of the same type in the output:

                   ffmpeg -i test1.avi -i test2.avi -map 1:1 -map 1:0 -map 0:1 -map 0:0 -c copy -y test12.nut

           The resulting output file test12.nut will contain the first four
           streams from the input files in reverse order.

       o   To force CBR video output:

                   ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v

       o   The four options lmin, lmax, mblmin and mblmax use 'lambda' units,
           but you may use the QP2LAMBDA constant to easily convert from 'q'
           units:

                   ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext


SEE ALSO

       ffmpeg-all(1), ffplay(1), ffprobe(1), ffmpeg-utils(1),
       ffmpeg-scaler(1), ffmpeg-resampler(1), ffmpeg-codecs(1),
       ffmpeg-bitstream-filters(1), ffmpeg-formats(1), ffmpeg-devices(1),
       ffmpeg-protocols(1), ffmpeg-filters(1)


AUTHORS

       The FFmpeg developers.

       For details about the authorship, see the Git history of the project
       (git://source.ffmpeg.org/ffmpeg), e.g. by typing the command git log in
       the FFmpeg source directory, or browsing the online repository at
       <http://source.ffmpeg.org>.

       Maintainers for the specific components are listed in the file
       MAINTAINERS in the source code tree.



                                                                     ffmpeg(1)

ffmpeg 4.4 - Generated Fri Apr 23 14:54:00 CDT 2021
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