--- /dev/null
- For QSV, this option corresponds to the valus of MFX_IMPL_* . Allowed values
+\input texinfo @c -*- texinfo -*-
+@documentencoding UTF-8
+
+@settitle ffmpeg Documentation
+@titlepage
+@center @titlefont{ffmpeg Documentation}
+@end titlepage
+
+@top
+
+@contents
+
+@chapter Synopsis
+
+ffmpeg [@var{global_options}] @{[@var{input_file_options}] -i @file{input_file}@} ... @{[@var{output_file_options}] @file{output_file}@} ...
+
+@chapter Description
+@c man begin DESCRIPTION
+
+@command{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.
+
+@command{ffmpeg} reads from an arbitrary number of input "files" (which can be regular
+files, pipes, network streams, grabbing devices, etc.), specified by the
+@code{-i} option, and writes to an arbitrary number of output "files", which are
+specified by a plain output filename. Anything found on the command line which
+cannot be interpreted as an option is considered to be an output filename.
+
+Each input or output file 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 @code{-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 @code{0}, the second is @code{1}, etc. Similarly, streams
+within a file are referred to by their indices. E.g. @code{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.
+
+@itemize
+@item
+To set the video bitrate of the output file to 64 kbit/s:
+@example
+ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi
+@end example
+
+@item
+To force the frame rate of the output file to 24 fps:
+@example
+ffmpeg -i input.avi -r 24 output.avi
+@end example
+
+@item
+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:
+@example
+ffmpeg -r 1 -i input.m2v -r 24 output.avi
+@end example
+@end itemize
+
+The format option may be needed for raw input files.
+
+@c man end DESCRIPTION
+
+@chapter Detailed description
+@c man begin DETAILED DESCRIPTION
+
+The transcoding process in @command{ffmpeg} for each output can be described by
+the following diagram:
+
+@verbatim
+ _______ ______________
+| | | |
+| input | demuxer | encoded data | decoder
+| file | ---------> | packets | -----+
+|_______| |______________| |
+ v
+ _________
+ | |
+ | decoded |
+ | frames |
+ |_________|
+ ________ ______________ |
+| | | | |
+| output | <-------- | encoded data | <----+
+| file | muxer | packets | encoder
+|________| |______________|
+
+
+@end verbatim
+
+@command{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, @command{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.
+
+@section Filtering
+Before encoding, @command{ffmpeg} can process raw audio and video frames using
+filters from the libavfilter library. Several chained filters form a filter
+graph. @command{ffmpeg} distinguishes between two types of filtergraphs:
+simple and complex.
+
+@subsection 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:
+
+@verbatim
+ _________ ______________
+| | | |
+| decoded | | encoded data |
+| frames |\ _ | packets |
+|_________| \ /||______________|
+ \ __________ /
+ simple _\|| | / encoder
+ filtergraph | filtered |/
+ | frames |
+ |__________|
+
+@end verbatim
+
+Simple filtergraphs are configured with the per-stream @option{-filter} option
+(with @option{-vf} and @option{-af} aliases for video and audio respectively).
+A simple filtergraph for video can look for example like this:
+
+@verbatim
+ _______ _____________ _______ ________
+| | | | | | | |
+| input | ---> | deinterlace | ---> | scale | ---> | output |
+|_______| |_____________| |_______| |________|
+
+@end verbatim
+
+Note that some filters change frame properties but not frame contents. E.g. the
+@code{fps} filter in the example above changes number of frames, but does not
+touch the frame contents. Another example is the @code{setpts} filter, which
+only sets timestamps and otherwise passes the frames unchanged.
+
+@subsection 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:
+
+@verbatim
+ _________
+| |
+| input 0 |\ __________
+|_________| \ | |
+ \ _________ /| output 0 |
+ \ | | / |__________|
+ _________ \| complex | /
+| | | |/
+| input 1 |---->| filter |\
+|_________| | | \ __________
+ /| graph | \ | |
+ / | | \| output 1 |
+ _________ / |_________| |__________|
+| | /
+| input 2 |/
+|_________|
+
+@end verbatim
+
+Complex filtergraphs are configured with the @option{-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 @option{-lavfi} option is equivalent to @option{-filter_complex}.
+
+A trivial example of a complex filtergraph is the @code{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 @code{amix} filter.
+
+@section Stream copy
+Stream copy is a mode selected by supplying the @code{copy} parameter to the
+@option{-codec} option. It makes @command{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:
+
+@verbatim
+ _______ ______________ ________
+| | | | | |
+| input | demuxer | encoded data | muxer | output |
+| file | ---------> | packets | -------> | file |
+|_______| |______________| |________|
+
+@end verbatim
+
+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.
+
+@c man end DETAILED DESCRIPTION
+
+@chapter Stream selection
+@c man begin STREAM SELECTION
+
+By default, @command{ffmpeg} includes only one stream of each type (video, audio, subtitle)
+present in the input files and adds them to each output file. It picks the
+"best" of each based upon the following criteria: for video, it is the stream
+with the highest resolution, for audio, it is the stream with the most channels, for
+subtitles, it is the first subtitle stream. In the case where several streams of
+the same type rate equally, the stream with the lowest index is chosen.
+
+You can disable some of those defaults by using the @code{-vn/-an/-sn} options. For
+full manual control, use the @code{-map} option, which disables the defaults just
+described.
+
+@c man end STREAM SELECTION
+
+@chapter Options
+@c man begin OPTIONS
+
+@include fftools-common-opts.texi
+
+@section Main options
+
+@table @option
+
+@item -f @var{fmt} (@emph{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.
+
+@item -i @var{filename} (@emph{input})
+input file name
+
+@item -y (@emph{global})
+Overwrite output files without asking.
+
+@item -n (@emph{global})
+Do not overwrite output files, and exit immediately if a specified
+output file already exists.
+
+@item -stream_loop @var{number} (@emph{input})
+Set number of times input stream shall be looped. Loop 0 means no loop,
+loop -1 means infinite loop.
+
+@item -c[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
+@itemx -codec[:@var{stream_specifier}] @var{codec} (@emph{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. @var{codec} is the name of a
+decoder/encoder or a special value @code{copy} (output only) to indicate that
+the stream is not to be re-encoded.
+
+For example
+@example
+ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT
+@end example
+encodes all video streams with libx264 and copies all audio streams.
+
+For each stream, the last matching @code{c} option is applied, so
+@example
+ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT
+@end example
+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.
+
+@item -t @var{duration} (@emph{input/output})
+When used as an input option (before @code{-i}), limit the @var{duration} of
+data read from the input file.
+
+When used as an output option (before an output filename), stop writing the
+output after its duration reaches @var{duration}.
+
+@var{duration} must be a time duration specification,
+see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
+
+-to and -t are mutually exclusive and -t has priority.
+
+@item -to @var{position} (@emph{output})
+Stop writing the output at @var{position}.
+@var{position} must be a time duration specification,
+see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
+
+-to and -t are mutually exclusive and -t has priority.
+
+@item -fs @var{limit_size} (@emph{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.
+
+@item -ss @var{position} (@emph{input/output})
+When used as an input option (before @code{-i}), seeks in this input file to
+@var{position}. Note that in most formats it is not possible to seek exactly,
+so @command{ffmpeg} will seek to the closest seek point before @var{position}.
+When transcoding and @option{-accurate_seek} is enabled (the default), this
+extra segment between the seek point and @var{position} will be decoded and
+discarded. When doing stream copy or when @option{-noaccurate_seek} is used, it
+will be preserved.
+
+When used as an output option (before an output filename), decodes but discards
+input until the timestamps reach @var{position}.
+
+@var{position} must be a time duration specification,
+see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
+
+@item -sseof @var{position} (@emph{input/output})
+
+Like the @code{-ss} option but relative to the "end of file". That is negative
+values are earlier in the file, 0 is at EOF.
+
+@item -itsoffset @var{offset} (@emph{input})
+Set the input time offset.
+
+@var{offset} must be a time duration specification,
+see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
+
+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 @var{offset}.
+
+@item -timestamp @var{date} (@emph{output})
+Set the recording timestamp in the container.
+
+@var{date} must be a date specification,
+see @ref{date syntax,,the Date section in the ffmpeg-utils(1) manual,ffmpeg-utils}.
+
+@item -metadata[:metadata_specifier] @var{key}=@var{value} (@emph{output,per-metadata})
+Set a metadata key/value pair.
+
+An optional @var{metadata_specifier} may be given to set metadata
+on streams, chapters or programs. See @code{-map_metadata}
+documentation for details.
+
+This option overrides metadata set with @code{-map_metadata}. It is
+also possible to delete metadata by using an empty value.
+
+For example, for setting the title in the output file:
+@example
+ffmpeg -i in.avi -metadata title="my title" out.flv
+@end example
+
+To set the language of the first audio stream:
+@example
+ffmpeg -i INPUT -metadata:s:a:0 language=eng OUTPUT
+@end example
+
+@item -program [title=@var{title}:][program_num=@var{program_num}:]st=@var{stream}[:st=@var{stream}...] (@emph{output})
+
+Creates a program with the specified @var{title}, @var{program_num} and adds the specified
+@var{stream}(s) to it.
+
+@item -target @var{type} (@emph{output})
+Specify target file type (@code{vcd}, @code{svcd}, @code{dvd}, @code{dv},
+@code{dv50}). @var{type} may be prefixed with @code{pal-}, @code{ntsc-} or
+@code{film-} to use the corresponding standard. All the format options
+(bitrate, codecs, buffer sizes) are then set automatically. You can just type:
+
+@example
+ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
+@end example
+
+Nevertheless you can specify additional options as long as you know
+they do not conflict with the standard, as in:
+
+@example
+ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
+@end example
+
+@item -dframes @var{number} (@emph{output})
+Set the number of data frames to output. This is an alias for @code{-frames:d}.
+
+@item -frames[:@var{stream_specifier}] @var{framecount} (@emph{output,per-stream})
+Stop writing to the stream after @var{framecount} frames.
+
+@item -q[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
+@itemx -qscale[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
+Use fixed quality scale (VBR). The meaning of @var{q}/@var{qscale} is
+codec-dependent.
+If @var{qscale} is used without a @var{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.
+
+@anchor{filter_option}
+@item -filter[:@var{stream_specifier}] @var{filtergraph} (@emph{output,per-stream})
+Create the filtergraph specified by @var{filtergraph} and use it to
+filter the stream.
+
+@var{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 @code{in}, and the output to the label @code{out}. See
+the ffmpeg-filters manual for more information about the filtergraph
+syntax.
+
+See the @ref{filter_complex_option,,-filter_complex option} if you
+want to create filtergraphs with multiple inputs and/or outputs.
+
+@item -filter_script[:@var{stream_specifier}] @var{filename} (@emph{output,per-stream})
+This option is similar to @option{-filter}, the only difference is that its
+argument is the name of the file from which a filtergraph description is to be
+read.
+
+@item -pre[:@var{stream_specifier}] @var{preset_name} (@emph{output,per-stream})
+Specify the preset for matching stream(s).
+
+@item -stats (@emph{global})
+Print encoding progress/statistics. It is on by default, to explicitly
+disable it you need to specify @code{-nostats}.
+
+@item -progress @var{url} (@emph{global})
+Send program-friendly progress information to @var{url}.
+
+Progress information is written approximately every second and at the end of
+the encoding process. It is made of "@var{key}=@var{value}" lines. @var{key}
+consists of only alphanumeric characters. The last key of a sequence of
+progress information is always "progress".
+
+@item -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
+@code{-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 @code{ffmpeg ... < /dev/null} but it requires a
+shell.
+
+@item -debug_ts (@emph{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 @code{-fdebug ts}.
+
+@item -attach @var{filename} (@emph{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 @code{-map} or automatic mappings).
+
+Note that for Matroska you also have to set the mimetype metadata tag:
+@example
+ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv
+@end example
+(assuming that the attachment stream will be third in the output file).
+
+@item -dump_attachment[:@var{stream_specifier}] @var{filename} (@emph{input,per-stream})
+Extract the matching attachment stream into a file named @var{filename}. If
+@var{filename} is empty, then the value of the @code{filename} metadata tag
+will be used.
+
+E.g. to extract the first attachment to a file named 'out.ttf':
+@example
+ffmpeg -dump_attachment:t:0 out.ttf -i INPUT
+@end example
+To extract all attachments to files determined by the @code{filename} tag:
+@example
+ffmpeg -dump_attachment:t "" -i INPUT
+@end example
+
+Technical note -- attachments are implemented as codec extradata, so this
+option can actually be used to extract extradata from any stream, not just
+attachments.
+
+@item -noautorotate
+Disable automatically rotating video based on file metadata.
+
+@end table
+
+@section Video Options
+
+@table @option
+@item -vframes @var{number} (@emph{output})
+Set the number of video frames to output. This is an alias for @code{-frames:v}.
+@item -r[:@var{stream_specifier}] @var{fps} (@emph{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 @var{fps}.
+This is not the same as the @option{-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 @option{-framerate} instead of the input option @option{-r}.
+
+As an output option, duplicate or drop input frames to achieve constant output
+frame rate @var{fps}.
+
+@item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream})
+Set frame size.
+
+As an input option, this is a shortcut for the @option{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 @code{scale} video filter to the
+@emph{end} of the corresponding filtergraph. Please use the @code{scale} filter
+directly to insert it at the beginning or some other place.
+
+The format is @samp{wxh} (default - same as source).
+
+@item -aspect[:@var{stream_specifier}] @var{aspect} (@emph{output,per-stream})
+Set the video display aspect ratio specified by @var{aspect}.
+
+@var{aspect} can be a floating point number string, or a string of the
+form @var{num}:@var{den}, where @var{num} and @var{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 @option{-vcodec copy}, it will affect the aspect ratio
+stored at container level, but not the aspect ratio stored in encoded
+frames, if it exists.
+
+@item -vn (@emph{output})
+Disable video recording.
+
+@item -vcodec @var{codec} (@emph{output})
+Set the video codec. This is an alias for @code{-codec:v}.
+
+@item -pass[:@var{stream_specifier}] @var{n} (@emph{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:
+@example
+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
+@end example
+
+@item -passlogfile[:@var{stream_specifier}] @var{prefix} (@emph{output,per-stream})
+Set two-pass log file name prefix to @var{prefix}, the default file name
+prefix is ``ffmpeg2pass''. The complete file name will be
+@file{PREFIX-N.log}, where N is a number specific to the output
+stream
+
+@item -vf @var{filtergraph} (@emph{output})
+Create the filtergraph specified by @var{filtergraph} and use it to
+filter the stream.
+
+This is an alias for @code{-filter:v}, see the @ref{filter_option,,-filter option}.
+@end table
+
+@section Advanced Video options
+
+@table @option
+@item -pix_fmt[:@var{stream_specifier}] @var{format} (@emph{input/output,per-stream})
+Set pixel format. Use @code{-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 @var{pix_fmt} is prefixed by a @code{+}, ffmpeg will exit with an error
+if the requested pixel format can not be selected, and automatic conversions
+inside filtergraphs are disabled.
+If @var{pix_fmt} is a single @code{+}, ffmpeg selects the same pixel format
+as the input (or graph output) and automatic conversions are disabled.
+
+@item -sws_flags @var{flags} (@emph{input/output})
+Set SwScaler flags.
+@item -vdt @var{n}
+Discard threshold.
+
+@item -rc_override[:@var{stream_specifier}] @var{override} (@emph{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.
+
+@item -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 with
+@option{-deinterlace}, but deinterlacing introduces losses.
+@item -psnr
+Calculate PSNR of compressed frames.
+@item -vstats
+Dump video coding statistics to @file{vstats_HHMMSS.log}.
+@item -vstats_file @var{file}
+Dump video coding statistics to @var{file}.
+@item -top[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
+top=1/bottom=0/auto=-1 field first
+@item -dc @var{precision}
+Intra_dc_precision.
+@item -vtag @var{fourcc/tag} (@emph{output})
+Force video tag/fourcc. This is an alias for @code{-tag:v}.
+@item -qphist (@emph{global})
+Show QP histogram
+@item -vbsf @var{bitstream_filter}
+Deprecated see -bsf
+
+@item -force_key_frames[:@var{stream_specifier}] @var{time}[,@var{time}...] (@emph{output,per-stream})
+@item -force_key_frames[:@var{stream_specifier}] expr:@var{expr} (@emph{output,per-stream})
+Force key frames at the specified timestamps, more precisely at the first
+frames after each specified time.
+
+If the argument is prefixed with @code{expr:}, the string @var{expr}
+is interpreted like an expression and is evaluated for each frame. A
+key frame is forced in case the evaluation is non-zero.
+
+If one of the times is "@code{chapters}[@var{delta}]", it is expanded into
+the time of the beginning of all chapters in the file, shifted by
+@var{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:
+@example
+-force_key_frames 0:05:00,chapters-0.1
+@end example
+
+The expression in @var{expr} can contain the following constants:
+@table @option
+@item n
+the number of current processed frame, starting from 0
+@item n_forced
+the number of forced frames
+@item prev_forced_n
+the number of the previous forced frame, it is @code{NAN} when no
+keyframe was forced yet
+@item prev_forced_t
+the time of the previous forced frame, it is @code{NAN} when no
+keyframe was forced yet
+@item t
+the time of the current processed frame
+@end table
+
+For example to force a key frame every 5 seconds, you can specify:
+@example
+-force_key_frames expr:gte(t,n_forced*5)
+@end example
+
+To force a key frame 5 seconds after the time of the last forced one,
+starting from second 13:
+@example
+-force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5))
+@end example
+
+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.
+
+@item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream})
+When doing stream copy, copy also non-key frames found at the
+beginning.
+
+@item -hwaccel[:@var{stream_specifier}] @var{hwaccel} (@emph{input,per-stream})
+Use hardware acceleration to decode the matching stream(s). The allowed values
+of @var{hwaccel} are:
+@table @option
+@item none
+Do not use any hardware acceleration (the default).
+
+@item auto
+Automatically select the hardware acceleration method.
+
+@item vda
+Use Apple VDA hardware acceleration.
+
+@item vdpau
+Use VDPAU (Video Decode and Presentation API for Unix) hardware acceleration.
+
+@item dxva2
+Use DXVA2 (DirectX Video Acceleration) hardware acceleration.
+
+@item 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.
+@end table
+
+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, @command{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.
+
+@item -hwaccel_device[:@var{stream_specifier}] @var{hwaccel_device} (@emph{input,per-stream})
+Select a device to use for hardware acceleration.
+
+This option only makes sense when the @option{-hwaccel} option is also
+specified. Its exact meaning depends on the specific hardware acceleration
+method chosen.
+
+@table @option
+@item vdpau
+For VDPAU, this option specifies the X11 display/screen to use. If this option
+is not specified, the value of the @var{DISPLAY} environment variable is used
+
+@item dxva2
+For DXVA2, this option should contain the number of the display adapter to use.
+If this option is not specified, the default adapter is used.
+
+@item qsv
++For QSV, this option corresponds to the values of MFX_IMPL_* . Allowed values
+are:
+@table @option
+@item auto
+@item sw
+@item hw
+@item auto_any
+@item hw_any
+@item hw2
+@item hw3
+@item hw4
+@end table
+@end table
+
+@item -hwaccels
+List all hardware acceleration methods supported in this build of ffmpeg.
+
+@end table
+
+@section Audio Options
+
+@table @option
+@item -aframes @var{number} (@emph{output})
+Set the number of audio frames to output. This is an alias for @code{-frames:a}.
+@item -ar[:@var{stream_specifier}] @var{freq} (@emph{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.
+@item -aq @var{q} (@emph{output})
+Set the audio quality (codec-specific, VBR). This is an alias for -q:a.
+@item -ac[:@var{stream_specifier}] @var{channels} (@emph{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.
+@item -an (@emph{output})
+Disable audio recording.
+@item -acodec @var{codec} (@emph{input/output})
+Set the audio codec. This is an alias for @code{-codec:a}.
+@item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream})
+Set the audio sample format. Use @code{-sample_fmts} to get a list
+of supported sample formats.
+
+@item -af @var{filtergraph} (@emph{output})
+Create the filtergraph specified by @var{filtergraph} and use it to
+filter the stream.
+
+This is an alias for @code{-filter:a}, see the @ref{filter_option,,-filter option}.
+@end table
+
+@section Advanced Audio options
+
+@table @option
+@item -atag @var{fourcc/tag} (@emph{output})
+Force audio tag/fourcc. This is an alias for @code{-tag:a}.
+@item -absf @var{bitstream_filter}
+Deprecated, see -bsf
+@item -guess_layout_max @var{channels} (@emph{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 @command{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.
+@end table
+
+@section Subtitle options
+
+@table @option
+@item -scodec @var{codec} (@emph{input/output})
+Set the subtitle codec. This is an alias for @code{-codec:s}.
+@item -sn (@emph{output})
+Disable subtitle recording.
+@item -sbsf @var{bitstream_filter}
+Deprecated, see -bsf
+@end table
+
+@section Advanced Subtitle options
+
+@table @option
+
+@item -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.
+
+@item -canvas_size @var{size}
+Set the size of the canvas used to render subtitles.
+
+@end table
+
+@section Advanced options
+
+@table @option
+@item -map [-]@var{input_file_id}[:@var{stream_specifier}][,@var{sync_file_id}[:@var{stream_specifier}]] | @var{[linklabel]} (@emph{output})
+
+Designate one or more input streams as a source for the output file. Each input
+stream is identified by the input file index @var{input_file_id} and
+the input stream index @var{input_stream_id} within the input
+file. Both indices start at 0. If specified,
+@var{sync_file_id}:@var{stream_specifier} sets which input stream
+is used as a presentation sync reference.
+
+The first @code{-map} option on the command line specifies the
+source for output stream 0, the second @code{-map} option specifies
+the source for output stream 1, etc.
+
+A @code{-} character before the stream identifier creates a "negative" mapping.
+It disables matching streams from already created mappings.
+
+An alternative @var{[linklabel]} form will map outputs from complex filter
+graphs (see the @option{-filter_complex} option) to the output file.
+@var{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
+@example
+ffmpeg -i INPUT -map 0 output
+@end example
+
+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
+@code{-map} to select which streams to place in an output file. For
+example:
+@example
+ffmpeg -i INPUT -map 0:1 out.wav
+@end example
+will map the input stream in @file{INPUT} identified by "0:1" to
+the (single) output stream in @file{out.wav}.
+
+For example, to select the stream with index 2 from input file
+@file{a.mov} (specified by the identifier "0:2"), and stream with
+index 6 from input @file{b.mov} (specified by the identifier "1:6"),
+and copy them to the output file @file{out.mov}:
+@example
+ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
+@end example
+
+To select all video and the third audio stream from an input file:
+@example
+ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT
+@end example
+
+To map all the streams except the second audio, use negative mappings
+@example
+ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT
+@end example
+
+To pick the English audio stream:
+@example
+ffmpeg -i INPUT -map 0:m:language:eng OUTPUT
+@end example
+
+Note that using this option disables the default mappings for this output file.
+
+@item -ignore_unknown
+Ignore input streams with unknown type instead of failing if copying
+such streams is attempted.
+
+@item -copy_unknown
+Allow input streams with unknown type to be copied instead of failing if copying
+such streams is attempted.
+
+@item -map_channel [@var{input_file_id}.@var{stream_specifier}.@var{channel_id}|-1][:@var{output_file_id}.@var{stream_specifier}]
+Map an audio channel from a given input to an output. If
+@var{output_file_id}.@var{stream_specifier} is not set, the audio channel will
+be mapped on all the audio streams.
+
+Using "-1" instead of
+@var{input_file_id}.@var{stream_specifier}.@var{channel_id} will map a muted
+channel.
+
+For example, assuming @var{INPUT} is a stereo audio file, you can switch the
+two audio channels with the following command:
+@example
+ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT
+@end example
+
+If you want to mute the first channel and keep the second:
+@example
+ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT
+@end example
+
+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 @var{INPUT} audio stream (file 0, stream 0)
+to the respective @var{OUTPUT_CH0} and @var{OUTPUT_CH1} outputs:
+@example
+ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1
+@end example
+
+The following example splits the channels of a stereo input into two separate
+streams, which are put into the same output file:
+@example
+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
+@end example
+
+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 @emph{amerge}
+filter. For example, if you need to merge a media (here @file{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:
+@example
+ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv
+@end example
+
+@item -map_metadata[:@var{metadata_spec_out}] @var{infile}[:@var{metadata_spec_in}] (@emph{output,per-metadata})
+Set metadata information of the next output file from @var{infile}. Note that
+those are file indices (zero-based), not filenames.
+Optional @var{metadata_spec_in/out} parameters specify, which metadata to copy.
+A metadata specifier can have the following forms:
+@table @option
+@item @var{g}
+global metadata, i.e. metadata that applies to the whole file
+
+@item @var{s}[:@var{stream_spec}]
+per-stream metadata. @var{stream_spec} is a stream specifier as described
+in the @ref{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.
+
+@item @var{c}:@var{chapter_index}
+per-chapter metadata. @var{chapter_index} is the zero-based chapter index.
+
+@item @var{p}:@var{program_index}
+per-program metadata. @var{program_index} is the zero-based program index.
+@end table
+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:
+@example
+ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3
+@end example
+
+To do the reverse, i.e. copy global metadata to all audio streams:
+@example
+ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv
+@end example
+Note that simple @code{0} would work as well in this example, since global
+metadata is assumed by default.
+
+@item -map_chapters @var{input_file_index} (@emph{output})
+Copy chapters from input file with index @var{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.
+
+@item -benchmark (@emph{global})
+Show benchmarking information at the end of an encode.
+Shows CPU time used and maximum memory consumption.
+Maximum memory consumption is not supported on all systems,
+it will usually display as 0 if not supported.
+@item -benchmark_all (@emph{global})
+Show benchmarking information during the encode.
+Shows CPU time used in various steps (audio/video encode/decode).
+@item -timelimit @var{duration} (@emph{global})
+Exit after ffmpeg has been running for @var{duration} seconds.
+@item -dump (@emph{global})
+Dump each input packet to stderr.
+@item -hex (@emph{global})
+When dumping packets, also dump the payload.
+@item -re (@emph{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 @command{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).
+@item -loop_input
+Loop over the input stream. Currently it works only for image
+streams. This option is used for automatic FFserver testing.
+This option is deprecated, use -loop 1.
+@item -loop_output @var{number_of_times}
+Repeatedly loop output for formats that support looping such as animated GIF
+(0 will loop the output infinitely).
+This option is deprecated, use -loop.
+@item -vsync @var{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.
+
+@table @option
+@item 0, passthrough
+Each frame is passed with its timestamp from the demuxer to the muxer.
+@item 1, cfr
+Frames will be duplicated and dropped to achieve exactly the requested
+constant frame rate.
+@item 2, vfr
+Frames are passed through with their timestamp or dropped so as to
+prevent 2 frames from having the same timestamp.
+@item drop
+As passthrough but destroys all timestamps, making the muxer generate
+fresh timestamps based on frame-rate.
+@item -1, auto
+Chooses between 1 and 2 depending on muxer capabilities. This is the
+default method.
+@end table
+
+Note that the timestamps may be further modified by the muxer, after this.
+For example, in the case that the format option @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.
+
+@item -frame_drop_threshold @var{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.
+
+@item -async @var{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 @option{avoid_negative_ts}
+is enabled.
+
+This option has been deprecated. Use the @code{aresample} audio filter instead.
+
+@item -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 @option{vsync} option or on specific muxer
+processing (e.g. in case the format option @option{avoid_negative_ts}
+is enabled) the output timestamps may mismatch with the input
+timestamps even when this option is selected.
+
+@item -start_at_zero
+When used with @option{copyts}, shift input timestamps so they start at zero.
+
+This means that using e.g. @code{-ss 50} will make output timestamps start at
+50 seconds, regardless of what timestamp the input file started at.
+
+@item -copytb @var{mode}
+Specify how to set the encoder timebase when stream copying. @var{mode} is an
+integer numeric value, and can assume one of the following values:
+
+@table @option
+@item 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.
+
+@item 0
+Use the decoder timebase.
+
+The time base is copied to the output encoder from the corresponding input
+decoder.
+
+@item -1
+Try to make the choice automatically, in order to generate a sane output.
+@end table
+
+Default value is -1.
+
+@item -shortest (@emph{output})
+Finish encoding when the shortest input stream ends.
+@item -dts_delta_threshold
+Timestamp discontinuity delta threshold.
+@item -muxdelay @var{seconds} (@emph{input})
+Set the maximum demux-decode delay.
+@item -muxpreload @var{seconds} (@emph{input})
+Set the initial demux-decode delay.
+@item -streamid @var{output-stream-index}:@var{new-value} (@emph{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:
+@example
+ffmpeg -i infile -streamid 0:33 -streamid 1:36 out.ts
+@end example
+
+@item -bsf[:@var{stream_specifier}] @var{bitstream_filters} (@emph{output,per-stream})
+Set bitstream filters for matching streams. @var{bitstream_filters} is
+a comma-separated list of bitstream filters. Use the @code{-bsfs} option
+to get the list of bitstream filters.
+@example
+ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264
+@end example
+@example
+ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt
+@end example
+
+@item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{input/output,per-stream})
+Force a tag/fourcc for matching streams.
+
+@item -timecode @var{hh}:@var{mm}:@var{ss}SEP@var{ff}
+Specify Timecode for writing. @var{SEP} is ':' for non drop timecode and ';'
+(or '.') for drop.
+@example
+ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg
+@end example
+
+@anchor{filter_complex_option}
+@item -filter_complex @var{filtergraph} (@emph{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 @option{-filter} options. @var{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
+@code{[file_index:stream_specifier]} syntax (i.e. the same as @option{-map}
+uses). If @var{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 @option{-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
+@example
+ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
+'[out]' out.mkv
+@end example
+Here @code{[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
+@example
+ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map
+'[out]' out.mkv
+@end example
+
+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
+@example
+ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv
+@end example
+
+To generate 5 seconds of pure red video using lavfi @code{color} source:
+@example
+ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv
+@end example
+
+@item -lavfi @var{filtergraph} (@emph{global})
+Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
+outputs. Equivalent to @option{-filter_complex}.
+
+@item -filter_complex_script @var{filename} (@emph{global})
+This option is similar to @option{-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.
+
+@item -accurate_seek (@emph{input})
+This option enables or disables accurate seeking in input files with the
+@option{-ss} option. It is enabled by default, so seeking is accurate when
+transcoding. Use @option{-noaccurate_seek} to disable it, which may be useful
+e.g. when copying some streams and transcoding the others.
+
+@item -seek_timestamp (@emph{input})
+This option enables or disables seeking by timestamp in input files with the
+@option{-ss} option. It is disabled by default. If enabled, the argument
+to the @option{-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.
+
+@item -thread_queue_size @var{size} (@emph{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; raising this value can
+avoid it.
+
+@item -override_ffserver (@emph{global})
+Overrides the input specifications from @command{ffserver}. Using this
+option you can map any input stream to @command{ffserver} and control
+many aspects of the encoding from @command{ffmpeg}. Without this
+option @command{ffmpeg} will transmit to @command{ffserver} what is
+requested by @command{ffserver}.
+
+The option is intended for cases where features are needed that cannot be
+specified to @command{ffserver} but can be to @command{ffmpeg}.
+
+@item -sdp_file @var{file} (@emph{global})
+Print sdp information for an output stream to @var{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).
+
+@item -discard (@emph{input})
+Allows discarding specific streams or frames of streams at the demuxer.
+Not all demuxers support this.
+
+@table @option
+@item none
+Discard no frame.
+
+@item default
+Default, which discards no frames.
+
+@item noref
+Discard all non-reference frames.
+
+@item bidir
+Discard all bidirectional frames.
+
+@item nokey
+Discard all frames excepts keyframes.
+
+@item all
+Discard all frames.
+@end table
+
+@item -abort_on @var{flags} (@emph{global})
+Stop and abort on various conditions. The following flags are available:
+
+@table @option
+@item empty_output
+No packets were passed to the muxer, the output is empty.
+@end table
+
+@item -xerror (@emph{global})
+Stop and exit on error
+
+@end table
+
+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:
+@example
+ffmpeg -i input.ts -filter_complex \
+ '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
+ -sn -map '#0x2dc' output.mkv
+@end example
+(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)
+
+@section Preset files
+A preset file contains a sequence of @var{option}=@var{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 @file{presets} directory in the FFmpeg source tree for examples.
+
+There are two types of preset files: ffpreset and avpreset files.
+
+@subsection ffpreset files
+ffpreset files are specified with the @code{vpre}, @code{apre},
+@code{spre}, and @code{fpre} options. The @code{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 @code{vpre}, @code{apre}, and
+@code{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 @code{vpre}, @code{apre}, and @code{spre}
+preset options identifies the preset file to use according to the
+following rules:
+
+First ffmpeg searches for a file named @var{arg}.ffpreset in the
+directories @file{$FFMPEG_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
+the datadir defined at configuration time (usually @file{PREFIX/share/ffmpeg})
+or in a @file{ffpresets} folder along the executable on win32,
+in that order. For example, if the argument is @code{libvpx-1080p}, it will
+search for the file @file{libvpx-1080p.ffpreset}.
+
+If no such file is found, then ffmpeg will search for a file named
+@var{codec_name}-@var{arg}.ffpreset in the above-mentioned
+directories, where @var{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 @code{-vcodec libvpx} and use @code{-vpre 1080p},
+then it will search for the file @file{libvpx-1080p.ffpreset}.
+
+@subsection avpreset files
+avpreset files are specified with the @code{pre} option. They work similar to
+ffpreset files, but they only allow encoder- specific options. Therefore, an
+@var{option}=@var{value} pair specifying an encoder cannot be used.
+
+When the @code{pre} option is specified, ffmpeg will look for files with the
+suffix .avpreset in the directories @file{$AVCONV_DATADIR} (if set), and
+@file{$HOME/.avconv}, and in the datadir defined at configuration time (usually
+@file{PREFIX/share/ffmpeg}), in that order.
+
+First ffmpeg searches for a file named @var{codec_name}-@var{arg}.avpreset in
+the above-mentioned directories, where @var{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 @code{-vcodec libvpx} and use @code{-pre 1080p}, then it will
+search for the file @file{libvpx-1080p.avpreset}.
+
+If no such file is found, then ffmpeg will search for a file named
+@var{arg}.avpreset in the same directories.
+
+@c man end OPTIONS
+
+@chapter Examples
+@c man begin EXAMPLES
+
+@section Video and Audio grabbing
+
+If you specify the input format and device then ffmpeg can grab video
+and audio directly.
+
+@example
+ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
+@end example
+
+Or with an ALSA audio source (mono input, card id 1) instead of OSS:
+@example
+ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg
+@end example
+
+Note that you must activate the right video source and channel before
+launching ffmpeg with any TV viewer such as
+@uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also
+have to set the audio recording levels correctly with a
+standard mixer.
+
+@section X11 grabbing
+
+Grab the X11 display with ffmpeg via
+
+@example
+ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0 /tmp/out.mpg
+@end example
+
+0.0 is display.screen number of your X11 server, same as
+the DISPLAY environment variable.
+
+@example
+ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0+10,20 /tmp/out.mpg
+@end example
+
+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.
+
+@section Video and Audio file format conversion
+
+Any supported file format and protocol can serve as input to ffmpeg:
+
+Examples:
+@itemize
+@item
+You can use YUV files as input:
+
+@example
+ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
+@end example
+
+It will use the files:
+@example
+/tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
+/tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
+@end example
+
+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 @option{-s} option
+if ffmpeg cannot guess it.
+
+@item
+You can input from a raw YUV420P file:
+
+@example
+ffmpeg -i /tmp/test.yuv /tmp/out.avi
+@end example
+
+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.
+
+@item
+You can output to a raw YUV420P file:
+
+@example
+ffmpeg -i mydivx.avi hugefile.yuv
+@end example
+
+@item
+You can set several input files and output files:
+
+@example
+ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
+@end example
+
+Converts the audio file a.wav and the raw YUV video file a.yuv
+to MPEG file a.mpg.
+
+@item
+You can also do audio and video conversions at the same time:
+
+@example
+ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
+@end example
+
+Converts a.wav to MPEG audio at 22050 Hz sample rate.
+
+@item
+You can encode to several formats at the same time and define a
+mapping from input stream to output streams:
+
+@example
+ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2
+@end example
+
+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.
+
+@item
+You can transcode decrypted VOBs:
+
+@example
+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
+@end example
+
+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 @code{--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 @code{ffmpeg -formats}.
+
+@item
+You can extract images from a video, or create a video from many images:
+
+For extracting images from a video:
+@example
+ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
+@end example
+
+This will extract one video frame per second from the video and will
+output them in files named @file{foo-001.jpeg}, @file{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 -vframes or -t option, or in
+combination with -ss to start extracting from a certain point in time.
+
+For creating a video from many images:
+@example
+ffmpeg -f image2 -framerate 12 -i foo-%03d.jpeg -s WxH foo.avi
+@end example
+
+The syntax @code{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 @code{-pattern_type glob} option.
+
+For example, for creating a video from filenames matching the glob pattern
+@code{foo-*.jpeg}:
+@example
+ffmpeg -f image2 -pattern_type glob -framerate 12 -i 'foo-*.jpeg' -s WxH foo.avi
+@end example
+
+@item
+You can put many streams of the same type in the output:
+
+@example
+ffmpeg -i test1.avi -i test2.avi -map 1:1 -map 1:0 -map 0:1 -map 0:0 -c copy -y test12.nut
+@end example
+
+The resulting output file @file{test12.nut} will contain the first four streams
+from the input files in reverse order.
+
+@item
+To force CBR video output:
+@example
+ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
+@end example
+
+@item
+The four options lmin, lmax, mblmin and mblmax use 'lambda' units,
+but you may use the QP2LAMBDA constant to easily convert from 'q' units:
+@example
+ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
+@end example
+
+@end itemize
+@c man end EXAMPLES
+
+@include config.texi
+@ifset config-all
+@ifset config-avutil
+@include utils.texi
+@end ifset
+@ifset config-avcodec
+@include codecs.texi
+@include bitstream_filters.texi
+@end ifset
+@ifset config-avformat
+@include formats.texi
+@include protocols.texi
+@end ifset
+@ifset config-avdevice
+@include devices.texi
+@end ifset
+@ifset config-swresample
+@include resampler.texi
+@end ifset
+@ifset config-swscale
+@include scaler.texi
+@end ifset
+@ifset config-avfilter
+@include filters.texi
+@end ifset
+@end ifset
+
+@chapter See Also
+
+@ifhtml
+@ifset config-all
+@url{ffmpeg.html,ffmpeg}
+@end ifset
+@ifset config-not-all
+@url{ffmpeg-all.html,ffmpeg-all},
+@end ifset
+@url{ffplay.html,ffplay}, @url{ffprobe.html,ffprobe}, @url{ffserver.html,ffserver},
+@url{ffmpeg-utils.html,ffmpeg-utils},
+@url{ffmpeg-scaler.html,ffmpeg-scaler},
+@url{ffmpeg-resampler.html,ffmpeg-resampler},
+@url{ffmpeg-codecs.html,ffmpeg-codecs},
+@url{ffmpeg-bitstream-filters.html,ffmpeg-bitstream-filters},
+@url{ffmpeg-formats.html,ffmpeg-formats},
+@url{ffmpeg-devices.html,ffmpeg-devices},
+@url{ffmpeg-protocols.html,ffmpeg-protocols},
+@url{ffmpeg-filters.html,ffmpeg-filters}
+@end ifhtml
+
+@ifnothtml
+@ifset config-all
+ffmpeg(1),
+@end ifset
+@ifset config-not-all
+ffmpeg-all(1),
+@end ifset
+ffplay(1), ffprobe(1), ffserver(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)
+@end ifnothtml
+
+@include authors.texi
+
+@ignore
+
+@setfilename ffmpeg
+@settitle ffmpeg video converter
+
+@end ignore
+
+@bye
@end table
-The default value of the select expression is "1".
+@subsection Examples
-Some examples:
+@itemize
+@item
+Halve the input audio volume:
+@example
+volume=volume=0.5
+volume=volume=1/2
+volume=volume=-6.0206dB
+@end example
+In all the above example the named key for @option{volume} can be
+omitted, for example like in:
@example
-# Select all the frames in input
-select
+volume=0.5
+@end example
-# The above is the same as
-select=expr=1
+@item
+Increase input audio power by 6 decibels using fixed-point precision:
+@example
+volume=volume=6dB:precision=fixed
+@end example
-# Skip all frames
-select=expr=0
+@item
+Fade volume after time 10 with an annihilation period of 5 seconds:
+@example
+volume='if(lt(t,10),1,max(1-(t-10)/5,0))':eval=frame
+@end example
+@end itemize
-# Select only I-frames
-select='expr=eq(pict_type\,I)'
+@section volumedetect
-# Select one frame per 100
-select='not(mod(n\,100))'
+Detect the volume of the input video.
-# Select only frames contained in the 10-20 time interval
-select='gte(t\,10)*lte(t\,20)'
+The filter has no parameters. The input is not modified. Statistics about
+the volume will be printed in the log when the input stream end is reached.
-# Select only I-frames contained in the 10-20 time interval
-select='gte(t\,10)*lte(t\,20)*eq(pict_type\,I)'
+In particular it will show the mean volume (root mean square), maximum
+volume (on a per-sample basis), and the beginning of a histogram of the
+registered volume values (from the maximum value to a cumulated 1/1000 of
+the samples).
-# Select frames with a minimum distance of 10 seconds
-select='isnan(prev_selected_t)+gte(t-prev_selected_t\,10)'
-@end example
+All volumes are in decibels relative to the maximum PCM value.
-@anchor{setdar}
-@section setdar
+@subsection Examples
-Set the Display Aspect Ratio for the filter output video.
+Here is an excerpt of the output:
+@example
+[Parsed_volumedetect_0 @ 0xa23120] mean_volume: -27 dB
+[Parsed_volumedetect_0 @ 0xa23120] max_volume: -4 dB
+[Parsed_volumedetect_0 @ 0xa23120] histogram_4db: 6
+[Parsed_volumedetect_0 @ 0xa23120] histogram_5db: 62
+[Parsed_volumedetect_0 @ 0xa23120] histogram_6db: 286
+[Parsed_volumedetect_0 @ 0xa23120] histogram_7db: 1042
+[Parsed_volumedetect_0 @ 0xa23120] histogram_8db: 2551
+[Parsed_volumedetect_0 @ 0xa23120] histogram_9db: 4609
+[Parsed_volumedetect_0 @ 0xa23120] histogram_10db: 8409
+@end example
-This is done by changing the specified Sample (aka Pixel) Aspect
-Ratio, according to the following equation:
-@math{DAR = HORIZONTAL_RESOLUTION / VERTICAL_RESOLUTION * SAR}
+It means that:
+@itemize
+@item
+The mean square energy is approximately -27 dB, or 10^-2.7.
+@item
+The largest sample is at -4 dB, or more precisely between -4 dB and -5 dB.
+@item
+There are 6 samples at -4 dB, 62 at -5 dB, 286 at -6 dB, etc.
+@end itemize
-Keep in mind that this filter does not modify the pixel dimensions of
-the video frame. Also, the display aspect ratio set by this filter may
-be changed by later filters in the filterchain, e.g. in case of
-scaling or if another "setdar" or a "setsar" filter is applied.
+In other words, raising the volume by +4 dB does not cause any clipping,
+raising it by +5 dB causes clipping for 6 samples, etc.
-It accepts the following parameters:
+@c man end AUDIO FILTERS
-@table @option
+@chapter Audio Sources
+@c man begin AUDIO SOURCES
-@item dar
-The output display aspect ratio.
+Below is a description of the currently available audio sources.
-@end table
+@section abuffer
-The parameter @var{dar} is an expression containing
-the following constants:
+Buffer audio frames, and make them available to the filter chain.
+
+This source is mainly intended for a programmatic use, in particular
+through the interface defined in @file{libavfilter/asrc_abuffer.h}.
+It accepts the following parameters:
@table @option
-@item E, PI, PHI
-These are approximated values for the mathematical constants e
-(Euler's number), pi (Greek pi), and phi (the golden ratio).
-@item w, h
-The input width and height.
+@item time_base
+The timebase which will be used for timestamps of submitted frames. It must be
+either a floating-point number or in @var{numerator}/@var{denominator} form.
-@item a
-This is the same as @var{w} / @var{h}.
+@item sample_rate
+The sample rate of the incoming audio buffers.
-@item sar
-The input sample aspect ratio.
+@item sample_fmt
+The sample format of the incoming audio buffers.
+Either a sample format name or its corresponding integer representation from
+the enum AVSampleFormat in @file{libavutil/samplefmt.h}
-@item dar
-The input display aspect ratio. It is the same as
-(@var{w} / @var{h}) * @var{sar}.
+@item channel_layout
+The channel layout of the incoming audio buffers.
+Either a channel layout name from channel_layout_map in
+@file{libavutil/channel_layout.c} or its corresponding integer representation
+from the AV_CH_LAYOUT_* macros in @file{libavutil/channel_layout.h}
+
+@item channels
+The number of channels of the incoming audio buffers.
+If both @var{channels} and @var{channel_layout} are specified, then they
+must be consistent.
-@item hsub, vsub
-The horizontal and vertical chroma subsample values. For example, for the
-pixel format "yuv422p" @var{hsub} is 2 and @var{vsub} is 1.
@end table
-To change the display aspect ratio to 16:9, specify:
+@subsection Examples
+
@example
-setdar=dar=16/9
-# The above is equivalent to
-setdar=dar=1.77777
+abuffer=sample_rate=44100:sample_fmt=s16p:channel_layout=stereo
+@end example
+
+will instruct the source to accept planar 16bit signed stereo at 44100Hz.
+Since the sample format with name "s16p" corresponds to the number
+6 and the "stereo" channel layout corresponds to the value 0x3, this is
+equivalent to:
+@example
+abuffer=sample_rate=44100:sample_fmt=6:channel_layout=0x3
@end example
-Also see the the @ref{setsar} filter documentation.
+@section aevalsrc
+
+Generate an audio signal specified by an expression.
+
+This source accepts in input one or more expressions (one for each
+channel), which are evaluated and used to generate a corresponding
+audio signal.
+
+This source accepts the following options:
+
+@table @option
+@item exprs
+Set the '|'-separated expressions list for each separate channel. In case the
+@option{channel_layout} option is not specified, the selected channel layout
+depends on the number of provided expressions. Otherwise the last
+specified expression is applied to the remaining output channels.
+
+@item channel_layout, c
+Set the channel layout. The number of channels in the specified layout
+must be equal to the number of specified expressions.
+
+@item duration, d
+Set the minimum duration of the sourced audio. See
+@ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) manual,ffmpeg-utils}
+for the accepted syntax.
+Note that the resulting duration may be greater than the specified
+duration, as the generated audio is always cut at the end of a
+complete frame.
+
+If not specified, or the expressed duration is negative, the audio is
+supposed to be generated forever.
+
+@item nb_samples, n
+Set the number of samples per channel per each output frame,
+default to 1024.
+
+@item sample_rate, s
+Specify the sample rate, default to 44100.
+@end table
+
+Each expression in @var{exprs} can contain the following constants:
+
+@table @option
+@item n
+number of the evaluated sample, starting from 0
+
+@item t
+time of the evaluated sample expressed in seconds, starting from 0
+
+@item s
+sample rate
+
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Generate silence:
+@example
+aevalsrc=0
+@end example
+
+@item
+Generate a sin signal with frequency of 440 Hz, set sample rate to
+8000 Hz:
+@example
+aevalsrc="sin(440*2*PI*t):s=8000"
+@end example
+
+@item
+Generate a two channels signal, specify the channel layout (Front
+Center + Back Center) explicitly:
+@example
+aevalsrc="sin(420*2*PI*t)|cos(430*2*PI*t):c=FC|BC"
+@end example
+
+@item
+Generate white noise:
+@example
+aevalsrc="-2+random(0)"
+@end example
+
+@item
+Generate an amplitude modulated signal:
+@example
+aevalsrc="sin(10*2*PI*t)*sin(880*2*PI*t)"
+@end example
+
+@item
+Generate 2.5 Hz binaural beats on a 360 Hz carrier:
+@example
+aevalsrc="0.1*sin(2*PI*(360-2.5/2)*t) | 0.1*sin(2*PI*(360+2.5/2)*t)"
+@end example
+
+@end itemize
+
+@section anullsrc
+
+The null audio source, return unprocessed audio frames. It is mainly useful
+as a template and to be employed in analysis / debugging tools, or as
+the source for filters which ignore the input data (for example the sox
+synth filter).
+
+This source accepts the following options:
+
+@table @option
+
+@item channel_layout, cl
+
+Specifies the channel layout, and can be either an integer or a string
+representing a channel layout. The default value of @var{channel_layout}
+is "stereo".
+
+Check the channel_layout_map definition in
+@file{libavutil/channel_layout.c} for the mapping between strings and
+channel layout values.
+
+@item sample_rate, r
+Specifies the sample rate, and defaults to 44100.
+
+@item nb_samples, n
+Set the number of samples per requested frames.
+
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Set the sample rate to 48000 Hz and the channel layout to AV_CH_LAYOUT_MONO.
+@example
+anullsrc=r=48000:cl=4
+@end example
+
+@item
+Do the same operation with a more obvious syntax:
+@example
+anullsrc=r=48000:cl=mono
+@end example
+@end itemize
+
+All the parameters need to be explicitly defined.
+
+@section flite
+
+Synthesize a voice utterance using the libflite library.
+
+To enable compilation of this filter you need to configure FFmpeg with
+@code{--enable-libflite}.
+
+Note that the flite library is not thread-safe.
+
+The filter accepts the following options:
+
+@table @option
+
+@item list_voices
+If set to 1, list the names of the available voices and exit
+immediately. Default value is 0.
+
+@item nb_samples, n
+Set the maximum number of samples per frame. Default value is 512.
+
+@item textfile
+Set the filename containing the text to speak.
+
+@item text
+Set the text to speak.
+
+@item voice, v
+Set the voice to use for the speech synthesis. Default value is
+@code{kal}. See also the @var{list_voices} option.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Read from file @file{speech.txt}, and synthesize the text using the
+standard flite voice:
+@example
+flite=textfile=speech.txt
+@end example
+
+@item
+Read the specified text selecting the @code{slt} voice:
+@example
+flite=text='So fare thee well, poor devil of a Sub-Sub, whose commentator I am':voice=slt
+@end example
+
+@item
+Input text to ffmpeg:
+@example
+ffmpeg -f lavfi -i flite=text='So fare thee well, poor devil of a Sub-Sub, whose commentator I am':voice=slt
+@end example
+
+@item
+Make @file{ffplay} speak the specified text, using @code{flite} and
+the @code{lavfi} device:
+@example
+ffplay -f lavfi flite=text='No more be grieved for which that thou hast done.'
+@end example
+@end itemize
+
+For more information about libflite, check:
+@url{http://www.speech.cs.cmu.edu/flite/}
+
+@section anoisesrc
+
+Generate a noise audio signal.
+
+The filter accepts the following options:
+
+@table @option
+@item sample_rate, r
+Specify the sample rate. Default value is 48000 Hz.
+
+@item amplitude, a
+Specify the amplitude (0.0 - 1.0) of the generated audio stream. Default value
+is 1.0.
+
+@item duration, d
+Specify the duration of the generated audio stream. Not specifying this option
+results in noise with an infinite length.
+
+@item color, colour, c
+Specify the color of noise. Available noise colors are white, pink, and brown.
+Default color is white.
+
+@item seed, s
+Specify a value used to seed the PRNG.
+
+@item nb_samples, n
+Set the number of samples per each output frame, default is 1024.
+@end table
+
+@subsection Examples
+
+@itemize
+
+@item
+Generate 60 seconds of pink noise, with a 44.1 kHz sampling rate and an amplitude of 0.5:
+@example
+anoisesrc=d=60:c=pink:r=44100:a=0.5
+@end example
+@end itemize
+
+@section sine
+
+Generate an audio signal made of a sine wave with amplitude 1/8.
+
+The audio signal is bit-exact.
+
+The filter accepts the following options:
+
+@table @option
+
+@item frequency, f
+Set the carrier frequency. Default is 440 Hz.
+
+@item beep_factor, b
+Enable a periodic beep every second with frequency @var{beep_factor} times
+the carrier frequency. Default is 0, meaning the beep is disabled.
+
+@item sample_rate, r
+Specify the sample rate, default is 44100.
+
+@item duration, d
+Specify the duration of the generated audio stream.
+
+@item samples_per_frame
+Set the number of samples per output frame.
+
+The expression can contain the following constants:
+
+@table @option
+@item n
+The (sequential) number of the output audio frame, starting from 0.
+
+@item pts
+The PTS (Presentation TimeStamp) of the output audio frame,
+expressed in @var{TB} units.
+
+@item t
+The PTS of the output audio frame, expressed in seconds.
+
+@item TB
+The timebase of the output audio frames.
+@end table
+
+Default is @code{1024}.
+@end table
+
+@subsection Examples
+
+@itemize
+
+@item
+Generate a simple 440 Hz sine wave:
+@example
+sine
+@end example
+
+@item
+Generate a 220 Hz sine wave with a 880 Hz beep each second, for 5 seconds:
+@example
+sine=220:4:d=5
+sine=f=220:b=4:d=5
+sine=frequency=220:beep_factor=4:duration=5
+@end example
+
+@item
+Generate a 1 kHz sine wave following @code{1602,1601,1602,1601,1602} NTSC
+pattern:
+@example
+sine=1000:samples_per_frame='st(0,mod(n,5)); 1602-not(not(eq(ld(0),1)+eq(ld(0),3)))'
+@end example
+@end itemize
+
+@c man end AUDIO SOURCES
+
+@chapter Audio Sinks
+@c man begin AUDIO SINKS
+
+Below is a description of the currently available audio sinks.
+
+@section abuffersink
+
+Buffer audio frames, and make them available to the end of filter chain.
+
+This sink is mainly intended for programmatic use, in particular
+through the interface defined in @file{libavfilter/buffersink.h}
+or the options system.
+
+It accepts a pointer to an AVABufferSinkContext structure, which
+defines the incoming buffers' formats, to be passed as the opaque
+parameter to @code{avfilter_init_filter} for initialization.
+@section anullsink
+
+Null audio sink; do absolutely nothing with the input audio. It is
+mainly useful as a template and for use in analysis / debugging
+tools.
+
+@c man end AUDIO SINKS
+
+@chapter Video Filters
+@c man begin VIDEO FILTERS
+
+When you configure your FFmpeg build, you can disable any of the
+existing filters using @code{--disable-filters}.
+The configure output will show the video filters included in your
+build.
+
+Below is a description of the currently available video filters.
+
+@section alphaextract
+
+Extract the alpha component from the input as a grayscale video. This
+is especially useful with the @var{alphamerge} filter.
+
+@section alphamerge
+
+Add or replace the alpha component of the primary input with the
+grayscale value of a second input. This is intended for use with
+@var{alphaextract} to allow the transmission or storage of frame
+sequences that have alpha in a format that doesn't support an alpha
+channel.
+
+For example, to reconstruct full frames from a normal YUV-encoded video
+and a separate video created with @var{alphaextract}, you might use:
+@example
+movie=in_alpha.mkv [alpha]; [in][alpha] alphamerge [out]
+@end example
+
+Since this filter is designed for reconstruction, it operates on frame
+sequences without considering timestamps, and terminates when either
+input reaches end of stream. This will cause problems if your encoding
+pipeline drops frames. If you're trying to apply an image as an
+overlay to a video stream, consider the @var{overlay} filter instead.
+
+@section ass
+
+Same as the @ref{subtitles} filter, except that it doesn't require libavcodec
+and libavformat to work. On the other hand, it is limited to ASS (Advanced
+Substation Alpha) subtitles files.
+
+This filter accepts the following option in addition to the common options from
+the @ref{subtitles} filter:
+
+@table @option
+@item shaping
+Set the shaping engine
+
+Available values are:
+@table @samp
+@item auto
+The default libass shaping engine, which is the best available.
+@item simple
+Fast, font-agnostic shaper that can do only substitutions
+@item complex
+Slower shaper using OpenType for substitutions and positioning
+@end table
+
+The default is @code{auto}.
+@end table
+
+@section atadenoise
+Apply an Adaptive Temporal Averaging Denoiser to the video input.
+
+The filter accepts the following options:
+
+@table @option
+@item 0a
+Set threshold A for 1st plane. Default is 0.02.
+Valid range is 0 to 0.3.
+
+@item 0b
+Set threshold B for 1st plane. Default is 0.04.
+Valid range is 0 to 5.
+
+@item 1a
+Set threshold A for 2nd plane. Default is 0.02.
+Valid range is 0 to 0.3.
+
+@item 1b
+Set threshold B for 2nd plane. Default is 0.04.
+Valid range is 0 to 5.
+
+@item 2a
+Set threshold A for 3rd plane. Default is 0.02.
+Valid range is 0 to 0.3.
+
+@item 2b
+Set threshold B for 3rd plane. Default is 0.04.
+Valid range is 0 to 5.
+
+Threshold A is designed to react on abrupt changes in the input signal and
+threshold B is designed to react on continuous changes in the input signal.
+
+@item s
+Set number of frames filter will use for averaging. Default is 33. Must be odd
+number in range [5, 129].
+@end table
+
+@section bbox
+
+Compute the bounding box for the non-black pixels in the input frame
+luminance plane.
+
+This filter computes the bounding box containing all the pixels with a
+luminance value greater than the minimum allowed value.
+The parameters describing the bounding box are printed on the filter
+log.
+
+The filter accepts the following option:
+
+@table @option
+@item min_val
+Set the minimal luminance value. Default is @code{16}.
+@end table
+
+@section blackdetect
+
+Detect video intervals that are (almost) completely black. Can be
+useful to detect chapter transitions, commercials, or invalid
+recordings. Output lines contains the time for the start, end and
+duration of the detected black interval expressed in seconds.
+
+In order to display the output lines, you need to set the loglevel at
+least to the AV_LOG_INFO value.
+
+The filter accepts the following options:
+
+@table @option
+@item black_min_duration, d
+Set the minimum detected black duration expressed in seconds. It must
+be a non-negative floating point number.
+
+Default value is 2.0.
+
+@item picture_black_ratio_th, pic_th
+Set the threshold for considering a picture "black".
+Express the minimum value for the ratio:
+@example
+@var{nb_black_pixels} / @var{nb_pixels}
+@end example
+
+for which a picture is considered black.
+Default value is 0.98.
+
+@item pixel_black_th, pix_th
+Set the threshold for considering a pixel "black".
+
+The threshold expresses the maximum pixel luminance value for which a
+pixel is considered "black". The provided value is scaled according to
+the following equation:
+@example
+@var{absolute_threshold} = @var{luminance_minimum_value} + @var{pixel_black_th} * @var{luminance_range_size}
+@end example
+
+@var{luminance_range_size} and @var{luminance_minimum_value} depend on
+the input video format, the range is [0-255] for YUV full-range
+formats and [16-235] for YUV non full-range formats.
+
+Default value is 0.10.
+@end table
+
+The following example sets the maximum pixel threshold to the minimum
+value, and detects only black intervals of 2 or more seconds:
+@example
+blackdetect=d=2:pix_th=0.00
+@end example
+
+@section blackframe
+
+Detect frames that are (almost) completely black. Can be useful to
+detect chapter transitions or commercials. Output lines consist of
+the frame number of the detected frame, the percentage of blackness,
+the position in the file if known or -1 and the timestamp in seconds.
+
+In order to display the output lines, you need to set the loglevel at
+least to the AV_LOG_INFO value.
+
+It accepts the following parameters:
+
+@table @option
+
+@item amount
+The percentage of the pixels that have to be below the threshold; it defaults to
+@code{98}.
+
+@item threshold, thresh
+The threshold below which a pixel value is considered black; it defaults to
+@code{32}.
+
+@end table
+
+@section blend, tblend
+
+Blend two video frames into each other.
+
+The @code{blend} filter takes two input streams and outputs one
+stream, the first input is the "top" layer and second input is
+"bottom" layer. Output terminates when shortest input terminates.
+
+The @code{tblend} (time blend) filter takes two consecutive frames
+from one single stream, and outputs the result obtained by blending
+the new frame on top of the old frame.
+
+A description of the accepted options follows.
+
+@table @option
+@item c0_mode
+@item c1_mode
+@item c2_mode
+@item c3_mode
+@item all_mode
+Set blend mode for specific pixel component or all pixel components in case
+of @var{all_mode}. Default value is @code{normal}.
+
+Available values for component modes are:
+@table @samp
+@item addition
+@item addition128
+@item and
+@item average
+@item burn
+@item darken
+@item difference
+@item difference128
+@item divide
+@item dodge
+@item freeze
+@item exclusion
+@item glow
+@item hardlight
+@item hardmix
+@item heat
+@item lighten
+@item linearlight
+@item multiply
+@item multiply128
+@item negation
+@item normal
+@item or
+@item overlay
+@item phoenix
+@item pinlight
+@item reflect
+@item screen
+@item softlight
+@item subtract
+@item vividlight
+@item xor
+@end table
+
+@item c0_opacity
+@item c1_opacity
+@item c2_opacity
+@item c3_opacity
+@item all_opacity
+Set blend opacity for specific pixel component or all pixel components in case
+of @var{all_opacity}. Only used in combination with pixel component blend modes.
+
+@item c0_expr
+@item c1_expr
+@item c2_expr
+@item c3_expr
+@item all_expr
+Set blend expression for specific pixel component or all pixel components in case
+of @var{all_expr}. Note that related mode options will be ignored if those are set.
+
+The expressions can use the following variables:
+
+@table @option
+@item N
+The sequential number of the filtered frame, starting from @code{0}.
+
+@item X
+@item Y
+the coordinates of the current sample
+
+@item W
+@item H
+the width and height of currently filtered plane
+
+@item SW
+@item SH
+Width and height scale depending on the currently filtered plane. It is the
+ratio between the corresponding luma plane number of pixels and the current
+plane ones. E.g. for YUV4:2:0 the values are @code{1,1} for the luma plane, and
+@code{0.5,0.5} for chroma planes.
+
+@item T
+Time of the current frame, expressed in seconds.
+
+@item TOP, A
+Value of pixel component at current location for first video frame (top layer).
+
+@item BOTTOM, B
+Value of pixel component at current location for second video frame (bottom layer).
+@end table
+
+@item shortest
+Force termination when the shortest input terminates. Default is
+@code{0}. This option is only defined for the @code{blend} filter.
+
+@item repeatlast
+Continue applying the last bottom frame after the end of the stream. A value of
+@code{0} disable the filter after the last frame of the bottom layer is reached.
+Default is @code{1}. This option is only defined for the @code{blend} filter.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Apply transition from bottom layer to top layer in first 10 seconds:
+@example
+blend=all_expr='A*(if(gte(T,10),1,T/10))+B*(1-(if(gte(T,10),1,T/10)))'
+@end example
+
+@item
+Apply 1x1 checkerboard effect:
+@example
+blend=all_expr='if(eq(mod(X,2),mod(Y,2)),A,B)'
+@end example
+
+@item
+Apply uncover left effect:
+@example
+blend=all_expr='if(gte(N*SW+X,W),A,B)'
+@end example
+
+@item
+Apply uncover down effect:
+@example
+blend=all_expr='if(gte(Y-N*SH,0),A,B)'
+@end example
+
+@item
+Apply uncover up-left effect:
+@example
+blend=all_expr='if(gte(T*SH*40+Y,H)*gte((T*40*SW+X)*W/H,W),A,B)'
+@end example
+
+@item
+Split diagonally video and shows top and bottom layer on each side:
+@example
+blend=all_expr=if(gt(X,Y*(W/H)),A,B)
+@end example
+
+@item
+Display differences between the current and the previous frame:
+@example
+tblend=all_mode=difference128
+@end example
+@end itemize
+
+@section boxblur
+
+Apply a boxblur algorithm to the input video.
+
+It accepts the following parameters:
+
+@table @option
+
+@item luma_radius, lr
+@item luma_power, lp
+@item chroma_radius, cr
+@item chroma_power, cp
+@item alpha_radius, ar
+@item alpha_power, ap
+
+@end table
+
+A description of the accepted options follows.
+
+@table @option
+@item luma_radius, lr
+@item chroma_radius, cr
+@item alpha_radius, ar
+Set an expression for the box radius in pixels used for blurring the
+corresponding input plane.
+
+The radius value must be a non-negative number, and must not be
+greater than the value of the expression @code{min(w,h)/2} for the
+luma and alpha planes, and of @code{min(cw,ch)/2} for the chroma
+planes.
+
+Default value for @option{luma_radius} is "2". If not specified,
+@option{chroma_radius} and @option{alpha_radius} default to the
+corresponding value set for @option{luma_radius}.
+
+The expressions can contain the following constants:
+@table @option
+@item w
+@item h
+The input width and height in pixels.
+
+@item cw
+@item ch
+The input chroma image width and height in pixels.
+
+@item hsub
+@item vsub
+The horizontal and vertical chroma subsample values. For example, for the
+pixel format "yuv422p", @var{hsub} is 2 and @var{vsub} is 1.
+@end table
+
+@item luma_power, lp
+@item chroma_power, cp
+@item alpha_power, ap
+Specify how many times the boxblur filter is applied to the
+corresponding plane.
+
+Default value for @option{luma_power} is 2. If not specified,
+@option{chroma_power} and @option{alpha_power} default to the
+corresponding value set for @option{luma_power}.
+
+A value of 0 will disable the effect.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Apply a boxblur filter with the luma, chroma, and alpha radii
+set to 2:
+@example
+boxblur=luma_radius=2:luma_power=1
+boxblur=2:1
+@end example
+
+@item
+Set the luma radius to 2, and alpha and chroma radius to 0:
+@example
+boxblur=2:1:cr=0:ar=0
+@end example
+
+@item
+Set the luma and chroma radii to a fraction of the video dimension:
+@example
+boxblur=luma_radius=min(h\,w)/10:luma_power=1:chroma_radius=min(cw\,ch)/10:chroma_power=1
+@end example
+@end itemize
+
+@section bwdif
+
+Deinterlace the input video ("bwdif" stands for "Bob Weaver
+Deinterlacing Filter").
+
+Motion adaptive deinterlacing based on yadif with the use of w3fdif and cubic
+interpolation algorithms.
+It accepts the following parameters:
+
+@table @option
+@item mode
+The interlacing mode to adopt. It accepts one of the following values:
+
+@table @option
+@item 0, send_frame
+Output one frame for each frame.
+@item 1, send_field
+Output one frame for each field.
+@end table
+
+The default value is @code{send_field}.
+
+@item parity
+The picture field parity assumed for the input interlaced video. It accepts one
+of the following values:
+
+@table @option
+@item 0, tff
+Assume the top field is first.
+@item 1, bff
+Assume the bottom field is first.
+@item -1, auto
+Enable automatic detection of field parity.
+@end table
+
+The default value is @code{auto}.
+If the interlacing is unknown or the decoder does not export this information,
+top field first will be assumed.
+
+@item deint
+Specify which frames to deinterlace. Accept one of the following
+values:
+
+@table @option
+@item 0, all
+Deinterlace all frames.
+@item 1, interlaced
+Only deinterlace frames marked as interlaced.
+@end table
+
+The default value is @code{all}.
+@end table
+
+@section chromakey
+YUV colorspace color/chroma keying.
+
+The filter accepts the following options:
+
+@table @option
+@item color
+The color which will be replaced with transparency.
+
+@item similarity
+Similarity percentage with the key color.
+
+0.01 matches only the exact key color, while 1.0 matches everything.
+
+@item blend
+Blend percentage.
+
+0.0 makes pixels either fully transparent, or not transparent at all.
+
+Higher values result in semi-transparent pixels, with a higher transparency
+the more similar the pixels color is to the key color.
+
+@item yuv
+Signals that the color passed is already in YUV instead of RGB.
+
+Litteral colors like "green" or "red" don't make sense with this enabled anymore.
+This can be used to pass exact YUV values as hexadecimal numbers.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Make every green pixel in the input image transparent:
+@example
+ffmpeg -i input.png -vf chromakey=green out.png
+@end example
+
+@item
+Overlay a greenscreen-video on top of a static black background.
+@example
+ffmpeg -f lavfi -i color=c=black:s=1280x720 -i video.mp4 -shortest -filter_complex "[1:v]chromakey=0x70de77:0.1:0.2[ckout];[0:v][ckout]overlay[out]" -map "[out]" output.mkv
+@end example
+@end itemize
+
+@section ciescope
+
+Display CIE color diagram with pixels overlaid onto it.
+
+The filter acccepts the following options:
+
+@table @option
+@item system
+Set color system.
+
+@table @samp
+@item ntsc, 470m
+@item ebu, 470bg
+@item smpte
+@item 240m
+@item apple
+@item widergb
+@item cie1931
+@item rec709, hdtv
+@item uhdtv, rec2020
+@end table
+
+@item cie
+Set CIE system.
+
+@table @samp
+@item xyy
+@item ucs
+@item luv
+@end table
+
+@item gamuts
+Set what gamuts to draw.
+
+See @code{system} option for avaiable values.
+
+@item size, s
+Set ciescope size, by default set to 512.
+
+@item intensity, i
+Set intensity used to map input pixel values to CIE diagram.
+
+@item contrast
+Set contrast used to draw tongue colors that are out of active color system gamut.
+
+@item corrgamma
+Correct gamma displayed on scope, by default enabled.
+
+@item showwhite
+Show white point on CIE diagram, by default disabled.
+
+@item gamma
+Set input gamma. Used only with XYZ input color space.
+@end table
+
+@section codecview
+
+Visualize information exported by some codecs.
+
+Some codecs can export information through frames using side-data or other
+means. For example, some MPEG based codecs export motion vectors through the
+@var{export_mvs} flag in the codec @option{flags2} option.
+
+The filter accepts the following option:
+
+@table @option
+@item mv
+Set motion vectors to visualize.
+
+Available flags for @var{mv} are:
+
+@table @samp
+@item pf
+forward predicted MVs of P-frames
+@item bf
+forward predicted MVs of B-frames
+@item bb
+backward predicted MVs of B-frames
+@end table
+
+@item qp
+Display quantization parameters using the chroma planes.
+
+@item mv_type, mvt
+Set motion vectors type to visualize. Includes MVs from all frames unless specified by @var{frame_type} option.
+
+Available flags for @var{mv_type} are:
+
+@table @samp
+@item fp
+forward predicted MVs
+@item bp
+backward predicted MVs
+@end table
+
+@item frame_type, ft
+Set frame type to visualize motion vectors of.
+
+Available flags for @var{frame_type} are:
+
+@table @samp
+@item if
+intra-coded frames (I-frames)
+@item pf
+predicted frames (P-frames)
+@item bf
+bi-directionally predicted frames (B-frames)
+@end table
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Visualize forward predicted MVs of all frames using @command{ffplay}:
+@example
+ffplay -flags2 +export_mvs input.mp4 -vf codecview=mv_type=fp
+@end example
+
+@item
+Visualize multi-directionals MVs of P and B-Frames using @command{ffplay}:
+@example
+ffplay -flags2 +export_mvs input.mp4 -vf codecview=mv=pf+bf+bb
+@end example
+@end itemize
+
+@section colorbalance
+Modify intensity of primary colors (red, green and blue) of input frames.
+
+The filter allows an input frame to be adjusted in the shadows, midtones or highlights
+regions for the red-cyan, green-magenta or blue-yellow balance.
+
+A positive adjustment value shifts the balance towards the primary color, a negative
+value towards the complementary color.
+
+The filter accepts the following options:
+
+@table @option
+@item rs
+@item gs
+@item bs
+Adjust red, green and blue shadows (darkest pixels).
+
+@item rm
+@item gm
+@item bm
+Adjust red, green and blue midtones (medium pixels).
+
+@item rh
+@item gh
+@item bh
+Adjust red, green and blue highlights (brightest pixels).
+
+Allowed ranges for options are @code{[-1.0, 1.0]}. Defaults are @code{0}.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Add red color cast to shadows:
+@example
+colorbalance=rs=.3
+@end example
+@end itemize
+
+@section colorkey
+RGB colorspace color keying.
+
+The filter accepts the following options:
+
+@table @option
+@item color
+The color which will be replaced with transparency.
+
+@item similarity
+Similarity percentage with the key color.
+
+0.01 matches only the exact key color, while 1.0 matches everything.
+
+@item blend
+Blend percentage.
+
+0.0 makes pixels either fully transparent, or not transparent at all.
+
+Higher values result in semi-transparent pixels, with a higher transparency
+the more similar the pixels color is to the key color.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Make every green pixel in the input image transparent:
+@example
+ffmpeg -i input.png -vf colorkey=green out.png
+@end example
+
+@item
+Overlay a greenscreen-video on top of a static background image.
+@example
+ffmpeg -i background.png -i video.mp4 -filter_complex "[1:v]colorkey=0x3BBD1E:0.3:0.2[ckout];[0:v][ckout]overlay[out]" -map "[out]" output.flv
+@end example
+@end itemize
+
+@section colorlevels
+
+Adjust video input frames using levels.
+
+The filter accepts the following options:
+
+@table @option
+@item rimin
+@item gimin
+@item bimin
+@item aimin
+Adjust red, green, blue and alpha input black point.
+Allowed ranges for options are @code{[-1.0, 1.0]}. Defaults are @code{0}.
+
+@item rimax
+@item gimax
+@item bimax
+@item aimax
+Adjust red, green, blue and alpha input white point.
+Allowed ranges for options are @code{[-1.0, 1.0]}. Defaults are @code{1}.
+
+Input levels are used to lighten highlights (bright tones), darken shadows
+(dark tones), change the balance of bright and dark tones.
+
+@item romin
+@item gomin
+@item bomin
+@item aomin
+Adjust red, green, blue and alpha output black point.
+Allowed ranges for options are @code{[0, 1.0]}. Defaults are @code{0}.
+
+@item romax
+@item gomax
+@item bomax
+@item aomax
+Adjust red, green, blue and alpha output white point.
+Allowed ranges for options are @code{[0, 1.0]}. Defaults are @code{1}.
+
+Output levels allows manual selection of a constrained output level range.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Make video output darker:
+@example
+colorlevels=rimin=0.058:gimin=0.058:bimin=0.058
+@end example
+
+@item
+Increase contrast:
+@example
+colorlevels=rimin=0.039:gimin=0.039:bimin=0.039:rimax=0.96:gimax=0.96:bimax=0.96
+@end example
+
+@item
+Make video output lighter:
+@example
+colorlevels=rimax=0.902:gimax=0.902:bimax=0.902
+@end example
+
+@item
+Increase brightness:
+@example
+colorlevels=romin=0.5:gomin=0.5:bomin=0.5
+@end example
+@end itemize
+
+@section colorchannelmixer
+
+Adjust video input frames by re-mixing color channels.
+
+This filter modifies a color channel by adding the values associated to
+the other channels of the same pixels. For example if the value to
+modify is red, the output value will be:
+@example
+@var{red}=@var{red}*@var{rr} + @var{blue}*@var{rb} + @var{green}*@var{rg} + @var{alpha}*@var{ra}
+@end example
+
+The filter accepts the following options:
+
+@table @option
+@item rr
+@item rg
+@item rb
+@item ra
+Adjust contribution of input red, green, blue and alpha channels for output red channel.
+Default is @code{1} for @var{rr}, and @code{0} for @var{rg}, @var{rb} and @var{ra}.
+
+@item gr
+@item gg
+@item gb
+@item ga
+Adjust contribution of input red, green, blue and alpha channels for output green channel.
+Default is @code{1} for @var{gg}, and @code{0} for @var{gr}, @var{gb} and @var{ga}.
+
+@item br
+@item bg
+@item bb
+@item ba
+Adjust contribution of input red, green, blue and alpha channels for output blue channel.
+Default is @code{1} for @var{bb}, and @code{0} for @var{br}, @var{bg} and @var{ba}.
+
+@item ar
+@item ag
+@item ab
+@item aa
+Adjust contribution of input red, green, blue and alpha channels for output alpha channel.
+Default is @code{1} for @var{aa}, and @code{0} for @var{ar}, @var{ag} and @var{ab}.
+
+Allowed ranges for options are @code{[-2.0, 2.0]}.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Convert source to grayscale:
+@example
+colorchannelmixer=.3:.4:.3:0:.3:.4:.3:0:.3:.4:.3
+@end example
+@item
+Simulate sepia tones:
+@example
+colorchannelmixer=.393:.769:.189:0:.349:.686:.168:0:.272:.534:.131
+@end example
+@end itemize
+
+@section colormatrix
+
+Convert color matrix.
+
+The filter accepts the following options:
+
+@table @option
+@item src
+@item dst
+Specify the source and destination color matrix. Both values must be
+specified.
+
+The accepted values are:
+@table @samp
+@item bt709
+BT.709
+
+@item bt601
+BT.601
+
+@item smpte240m
+SMPTE-240M
+
+@item fcc
+FCC
+
+@item bt2020
+BT.2020
+@end table
+@end table
+
+For example to convert from BT.601 to SMPTE-240M, use the command:
+@example
+colormatrix=bt601:smpte240m
+@end example
+
+@section colorspace
+
+Convert colorspace, transfer characteristics or color primaries.
+
+The filter accepts the following options:
+
+@table @option
+@item all
+Specify all color properties at once.
+
+The accepted values are:
+@table @samp
+@item bt470m
+BT.470M
+
+@item bt470bg
+BT.470BG
+
+@item bt601-6-525
+BT.601-6 525
+
+@item bt601-6-625
+BT.601-6 625
+
+@item bt709
+BT.709
+
+@item smpte170m
+SMPTE-170M
+
+@item smpte240m
+SMPTE-240M
+
+@item bt2020
+BT.2020
+
+@end table
+
+@item space
+Specify output colorspace.
+
+The accepted values are:
+@table @samp
+@item bt709
+BT.709
+
+@item fcc
+FCC
+
+@item bt470bg
+BT.470BG or BT.601-6 625
+
+@item smpte170m
+SMPTE-170M or BT.601-6 525
+
+@item smpte240m
+SMPTE-240M
+
+@item bt2020ncl
+BT.2020 with non-constant luminance
+
+@end table
+
+@item trc
+Specify output transfer characteristics.
+
+The accepted values are:
+@table @samp
+@item bt709
+BT.709
+
+@item gamma22
+Constant gamma of 2.2
+
+@item gamma28
+Constant gamma of 2.8
+
+@item smpte170m
+SMPTE-170M, BT.601-6 625 or BT.601-6 525
+
+@item smpte240m
+SMPTE-240M
+
+@item bt2020-10
+BT.2020 for 10-bits content
+
+@item bt2020-12
+BT.2020 for 12-bits content
+
+@end table
+
+@item prm
+Specify output color primaries.
+
+The accepted values are:
+@table @samp
+@item bt709
+BT.709
+
+@item bt470m
+BT.470M
+
+@item bt470bg
+BT.470BG or BT.601-6 625
+
+@item smpte170m
+SMPTE-170M or BT.601-6 525
+
+@item smpte240m
+SMPTE-240M
+
+@item bt2020
+BT.2020
+
+@end table
+
+@item rng
+Specify output color range.
+
+The accepted values are:
+@table @samp
+@item mpeg
+MPEG (restricted) range
+
+@item jpeg
+JPEG (full) range
+
+@end table
+
+@item format
+Specify output color format.
+
+The accepted values are:
+@table @samp
+@item yuv420p
+YUV 4:2:0 planar 8-bits
+
+@item yuv420p10
+YUV 4:2:0 planar 10-bits
+
+@item yuv420p12
+YUV 4:2:0 planar 12-bits
+
+@item yuv422p
+YUV 4:2:2 planar 8-bits
+
+@item yuv422p10
+YUV 4:2:2 planar 10-bits
+
+@item yuv422p12
+YUV 4:2:2 planar 12-bits
+
+@item yuv444p
+YUV 4:4:4 planar 8-bits
+
+@item yuv444p10
+YUV 4:4:4 planar 10-bits
+
+@item yuv444p12
+YUV 4:4:4 planar 12-bits
+
+@end table
+
+@item fast
+Do a fast conversion, which skips gamma/primary correction. This will take
+significantly less CPU, but will be mathematically incorrect. To get output
+compatible with that produced by the colormatrix filter, use fast=1.
+
+@item dither
+Specify dithering mode.
+
+The accepted values are:
+@table @samp
+@item none
+No dithering
+
+@item fsb
+Floyd-Steinberg dithering
+@end table
+
+@item wpadapt
+Whitepoint adaptation mode.
+
+The accepted values are:
+@table @samp
+@item bradford
+Bradford whitepoint adaptation
+
+@item vonkries
+von Kries whitepoint adaptation
+
+@item identity
+identity whitepoint adaptation (i.e. no whitepoint adaptation)
+@end table
+
+@end table
+
+The filter converts the transfer characteristics, color space and color
+primaries to the specified user values. The output value, if not specified,
+is set to a default value based on the "all" property. If that property is
+also not specified, the filter will log an error. The output color range and
+format default to the same value as the input color range and format. The
+input transfer characteristics, color space, color primaries and color range
+should be set on the input data. If any of these are missing, the filter will
+log an error and no conversion will take place.
+
+For example to convert the input to SMPTE-240M, use the command:
+@example
+colorspace=smpte240m
+@end example
+
+@section convolution
+
+Apply convolution 3x3 or 5x5 filter.
+
+The filter accepts the following options:
+
+@table @option
+@item 0m
+@item 1m
+@item 2m
+@item 3m
+Set matrix for each plane.
+Matrix is sequence of 9 or 25 signed integers.
+
+@item 0rdiv
+@item 1rdiv
+@item 2rdiv
+@item 3rdiv
+Set multiplier for calculated value for each plane.
+
+@item 0bias
+@item 1bias
+@item 2bias
+@item 3bias
+Set bias for each plane. This value is added to the result of the multiplication.
+Useful for making the overall image brighter or darker. Default is 0.0.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Apply sharpen:
+@example
+convolution="0 -1 0 -1 5 -1 0 -1 0:0 -1 0 -1 5 -1 0 -1 0:0 -1 0 -1 5 -1 0 -1 0:0 -1 0 -1 5 -1 0 -1 0"
+@end example
+
+@item
+Apply blur:
+@example
+convolution="1 1 1 1 1 1 1 1 1:1 1 1 1 1 1 1 1 1:1 1 1 1 1 1 1 1 1:1 1 1 1 1 1 1 1 1:1/9:1/9:1/9:1/9"
+@end example
+
+@item
+Apply edge enhance:
+@example
+convolution="0 0 0 -1 1 0 0 0 0:0 0 0 -1 1 0 0 0 0:0 0 0 -1 1 0 0 0 0:0 0 0 -1 1 0 0 0 0:5:1:1:1:0:128:128:128"
+@end example
+
+@item
+Apply edge detect:
+@example
+convolution="0 1 0 1 -4 1 0 1 0:0 1 0 1 -4 1 0 1 0:0 1 0 1 -4 1 0 1 0:0 1 0 1 -4 1 0 1 0:5:5:5:1:0:128:128:128"
+@end example
+
+@item
+Apply emboss:
+@example
+convolution="-2 -1 0 -1 1 1 0 1 2:-2 -1 0 -1 1 1 0 1 2:-2 -1 0 -1 1 1 0 1 2:-2 -1 0 -1 1 1 0 1 2"
+@end example
+@end itemize
+
+@section copy
+
+Copy the input source unchanged to the output. This is mainly useful for
+testing purposes.
+
+@anchor{coreimage}
+@section coreimage
+Video filtering on GPU using Apple's CoreImage API on OSX.
+
+Hardware acceleration is based on an OpenGL context. Usually, this means it is
+processed by video hardware. However, software-based OpenGL implementations
+exist which means there is no guarantee for hardware processing. It depends on
+the respective OSX.
+
+There are many filters and image generators provided by Apple that come with a
+large variety of options. The filter has to be referenced by its name along
+with its options.
+
+The coreimage filter accepts the following options:
+@table @option
+@item list_filters
+List all available filters and generators along with all their respective
+options as well as possible minimum and maximum values along with the default
+values.
+@example
+list_filters=true
+@end example
+
+@item filter
+Specify all filters by their respective name and options.
+Use @var{list_filters} to determine all valid filter names and options.
+Numerical options are specified by a float value and are automatically clamped
+to their respective value range. Vector and color options have to be specified
+by a list of space separated float values. Character escaping has to be done.
+A special option name @code{default} is available to use default options for a
+filter.
+
+It is required to specify either @code{default} or at least one of the filter options.
+All omitted options are used with their default values.
+The syntax of the filter string is as follows:
+@example
+filter=<NAME>@@<OPTION>=<VALUE>[@@<OPTION>=<VALUE>][@@...][#<NAME>@@<OPTION>=<VALUE>[@@<OPTION>=<VALUE>][@@...]][#...]
+@end example
+
+@item output_rect
+Specify a rectangle where the output of the filter chain is copied into the
+input image. It is given by a list of space separated float values:
+@example
+output_rect=x\ y\ width\ height
+@end example
+If not given, the output rectangle equals the dimensions of the input image.
+The output rectangle is automatically cropped at the borders of the input
+image. Negative values are valid for each component.
+@example
+output_rect=25\ 25\ 100\ 100
+@end example
+@end table
+
+Several filters can be chained for successive processing without GPU-HOST
+transfers allowing for fast processing of complex filter chains.
+Currently, only filters with zero (generators) or exactly one (filters) input
+image and one output image are supported. Also, transition filters are not yet
+usable as intended.
+
+Some filters generate output images with additional padding depending on the
+respective filter kernel. The padding is automatically removed to ensure the
+filter output has the same size as the input image.
+
+For image generators, the size of the output image is determined by the
+previous output image of the filter chain or the input image of the whole
+filterchain, respectively. The generators do not use the pixel information of
+this image to generate their output. However, the generated output is
+blended onto this image, resulting in partial or complete coverage of the
+output image.
+
+The @ref{coreimagesrc} video source can be used for generating input images
+which are directly fed into the filter chain. By using it, providing input
+images by another video source or an input video is not required.
+
+@subsection Examples
+
+@itemize
+
+@item
+List all filters available:
+@example
+coreimage=list_filters=true
+@end example
+
+@item
+Use the CIBoxBlur filter with default options to blur an image:
+@example
+coreimage=filter=CIBoxBlur@@default
+@end example
+
+@item
+Use a filter chain with CISepiaTone at default values and CIVignetteEffect with
+its center at 100x100 and a radius of 50 pixels:
+@example
+coreimage=filter=CIBoxBlur@@default#CIVignetteEffect@@inputCenter=100\ 100@@inputRadius=50
+@end example
+
+@item
+Use nullsrc and CIQRCodeGenerator to create a QR code for the FFmpeg homepage,
+given as complete and escaped command-line for Apple's standard bash shell:
+@example
+ffmpeg -f lavfi -i nullsrc=s=100x100,coreimage=filter=CIQRCodeGenerator@@inputMessage=https\\\\\://FFmpeg.org/@@inputCorrectionLevel=H -frames:v 1 QRCode.png
+@end example
+@end itemize
+
+@section crop
+
+Crop the input video to given dimensions.
+
+It accepts the following parameters:
+
+@table @option
+@item w, out_w
+The width of the output video. It defaults to @code{iw}.
+This expression is evaluated only once during the filter
+configuration, or when the @samp{w} or @samp{out_w} command is sent.
+
+@item h, out_h
+The height of the output video. It defaults to @code{ih}.
+This expression is evaluated only once during the filter
+configuration, or when the @samp{h} or @samp{out_h} command is sent.
+
+@item x
+The horizontal position, in the input video, of the left edge of the output
+video. It defaults to @code{(in_w-out_w)/2}.
+This expression is evaluated per-frame.
+
+@item y
+The vertical position, in the input video, of the top edge of the output video.
+It defaults to @code{(in_h-out_h)/2}.
+This expression is evaluated per-frame.
+
+@item keep_aspect
+If set to 1 will force the output display aspect ratio
+to be the same of the input, by changing the output sample aspect
+ratio. It defaults to 0.
+@end table
+
+The @var{out_w}, @var{out_h}, @var{x}, @var{y} parameters are
+expressions containing the following constants:
+
+@table @option
+@item x
+@item y
+The computed values for @var{x} and @var{y}. They are evaluated for
+each new frame.
+
+@item in_w
+@item in_h
+The input width and height.
+
+@item iw
+@item ih
+These are the same as @var{in_w} and @var{in_h}.
+
+@item out_w
+@item out_h
+The output (cropped) width and height.
+
+@item ow
+@item oh
+These are the same as @var{out_w} and @var{out_h}.
+
+@item a
+same as @var{iw} / @var{ih}
+
+@item sar
+input sample aspect ratio
+
+@item dar
+input display aspect ratio, it is the same as (@var{iw} / @var{ih}) * @var{sar}
+
+@item hsub
+@item vsub
+horizontal and vertical chroma subsample values. For example for the
+pixel format "yuv422p" @var{hsub} is 2 and @var{vsub} is 1.
+
+@item n
+The number of the input frame, starting from 0.
+
+@item pos
+the position in the file of the input frame, NAN if unknown
+
+@item t
+The timestamp expressed in seconds. It's NAN if the input timestamp is unknown.
+
+@end table
+
+The expression for @var{out_w} may depend on the value of @var{out_h},
+and the expression for @var{out_h} may depend on @var{out_w}, but they
+cannot depend on @var{x} and @var{y}, as @var{x} and @var{y} are
+evaluated after @var{out_w} and @var{out_h}.
+
+The @var{x} and @var{y} parameters specify the expressions for the
+position of the top-left corner of the output (non-cropped) area. They
+are evaluated for each frame. If the evaluated value is not valid, it
+is approximated to the nearest valid value.
+
+The expression for @var{x} may depend on @var{y}, and the expression
+for @var{y} may depend on @var{x}.
+
+@subsection Examples
+
+@itemize
+@item
+Crop area with size 100x100 at position (12,34).
+@example
+crop=100:100:12:34
+@end example
+
+Using named options, the example above becomes:
+@example
+crop=w=100:h=100:x=12:y=34
+@end example
+
+@item
+Crop the central input area with size 100x100:
+@example
+crop=100:100
+@end example
+
+@item
+Crop the central input area with size 2/3 of the input video:
+@example
+crop=2/3*in_w:2/3*in_h
+@end example
+
+@item
+Crop the input video central square:
+@example
+crop=out_w=in_h
+crop=in_h
+@end example
+
+@item
+Delimit the rectangle with the top-left corner placed at position
+100:100 and the right-bottom corner corresponding to the right-bottom
+corner of the input image.
+@example
+crop=in_w-100:in_h-100:100:100
+@end example
+
+@item
+Crop 10 pixels from the left and right borders, and 20 pixels from
+the top and bottom borders
+@example
+crop=in_w-2*10:in_h-2*20
+@end example
+
+@item
+Keep only the bottom right quarter of the input image:
+@example
+crop=in_w/2:in_h/2:in_w/2:in_h/2
+@end example
+
+@item
+Crop height for getting Greek harmony:
+@example
+crop=in_w:1/PHI*in_w
+@end example
+
+@item
+Apply trembling effect:
+@example
+crop=in_w/2:in_h/2:(in_w-out_w)/2+((in_w-out_w)/2)*sin(n/10):(in_h-out_h)/2 +((in_h-out_h)/2)*sin(n/7)
+@end example
+
+@item
+Apply erratic camera effect depending on timestamp:
+@example
+crop=in_w/2:in_h/2:(in_w-out_w)/2+((in_w-out_w)/2)*sin(t*10):(in_h-out_h)/2 +((in_h-out_h)/2)*sin(t*13)"
+@end example
+
+@item
+Set x depending on the value of y:
+@example
+crop=in_w/2:in_h/2:y:10+10*sin(n/10)
+@end example
+@end itemize
+
+@subsection Commands
+
+This filter supports the following commands:
+@table @option
+@item w, out_w
+@item h, out_h
+@item x
+@item y
+Set width/height of the output video and the horizontal/vertical position
+in the input video.
+The command accepts the same syntax of the corresponding option.
+
+If the specified expression is not valid, it is kept at its current
+value.
+@end table
+
+@section cropdetect
+
+Auto-detect the crop size.
+
+It calculates the necessary cropping parameters and prints the
+recommended parameters via the logging system. The detected dimensions
+correspond to the non-black area of the input video.
+
+It accepts the following parameters:
+
+@table @option
+
+@item limit
+Set higher black value threshold, which can be optionally specified
- from nothing (0) to everything (255 for 8bit based formats). An intensity
++from nothing (0) to everything (255 for 8-bit based formats). An intensity
+value greater to the set value is considered non-black. It defaults to 24.
+You can also specify a value between 0.0 and 1.0 which will be scaled depending
+on the bitdepth of the pixel format.
+
+@item round
+The value which the width/height should be divisible by. It defaults to
+16. The offset is automatically adjusted to center the video. Use 2 to
+get only even dimensions (needed for 4:2:2 video). 16 is best when
+encoding to most video codecs.
+
+@item reset_count, reset
+Set the counter that determines after how many frames cropdetect will
+reset the previously detected largest video area and start over to
+detect the current optimal crop area. Default value is 0.
+
+This can be useful when channel logos distort the video area. 0
+indicates 'never reset', and returns the largest area encountered during
+playback.
+@end table
+
+@anchor{curves}
+@section curves
+
+Apply color adjustments using curves.
+
+This filter is similar to the Adobe Photoshop and GIMP curves tools. Each
+component (red, green and blue) has its values defined by @var{N} key points
+tied from each other using a smooth curve. The x-axis represents the pixel
+values from the input frame, and the y-axis the new pixel values to be set for
+the output frame.
+
+By default, a component curve is defined by the two points @var{(0;0)} and
+@var{(1;1)}. This creates a straight line where each original pixel value is
+"adjusted" to its own value, which means no change to the image.
+
+The filter allows you to redefine these two points and add some more. A new
+curve (using a natural cubic spline interpolation) will be define to pass
+smoothly through all these new coordinates. The new defined points needs to be
+strictly increasing over the x-axis, and their @var{x} and @var{y} values must
+be in the @var{[0;1]} interval. If the computed curves happened to go outside
+the vector spaces, the values will be clipped accordingly.
+
+If there is no key point defined in @code{x=0}, the filter will automatically
+insert a @var{(0;0)} point. In the same way, if there is no key point defined
+in @code{x=1}, the filter will automatically insert a @var{(1;1)} point.
+
+The filter accepts the following options:
+
+@table @option
+@item preset
+Select one of the available color presets. This option can be used in addition
+to the @option{r}, @option{g}, @option{b} parameters; in this case, the later
+options takes priority on the preset values.
+Available presets are:
+@table @samp
+@item none
+@item color_negative
+@item cross_process
+@item darker
+@item increase_contrast
+@item lighter
+@item linear_contrast
+@item medium_contrast
+@item negative
+@item strong_contrast
+@item vintage
+@end table
+Default is @code{none}.
+@item master, m
+Set the master key points. These points will define a second pass mapping. It
+is sometimes called a "luminance" or "value" mapping. It can be used with
+@option{r}, @option{g}, @option{b} or @option{all} since it acts like a
+post-processing LUT.
+@item red, r
+Set the key points for the red component.
+@item green, g
+Set the key points for the green component.
+@item blue, b
+Set the key points for the blue component.
+@item all
+Set the key points for all components (not including master).
+Can be used in addition to the other key points component
+options. In this case, the unset component(s) will fallback on this
+@option{all} setting.
+@item psfile
+Specify a Photoshop curves file (@code{.acv}) to import the settings from.
+@end table
+
+To avoid some filtergraph syntax conflicts, each key points list need to be
+defined using the following syntax: @code{x0/y0 x1/y1 x2/y2 ...}.
+
+@subsection Examples
+
+@itemize
+@item
+Increase slightly the middle level of blue:
+@example
+curves=blue='0.5/0.58'
+@end example
+
+@item
+Vintage effect:
+@example
+curves=r='0/0.11 .42/.51 1/0.95':g='0.50/0.48':b='0/0.22 .49/.44 1/0.8'
+@end example
+Here we obtain the following coordinates for each components:
+@table @var
+@item red
+@code{(0;0.11) (0.42;0.51) (1;0.95)}
+@item green
+@code{(0;0) (0.50;0.48) (1;1)}
+@item blue
+@code{(0;0.22) (0.49;0.44) (1;0.80)}
+@end table
+
+@item
+The previous example can also be achieved with the associated built-in preset:
+@example
+curves=preset=vintage
+@end example
+
+@item
+Or simply:
+@example
+curves=vintage
+@end example
+
+@item
+Use a Photoshop preset and redefine the points of the green component:
+@example
+curves=psfile='MyCurvesPresets/purple.acv':green='0.45/0.53'
+@end example
+@end itemize
+
+@section datascope
+
+Video data analysis filter.
+
+This filter shows hexadecimal pixel values of part of video.
+
+The filter accepts the following options:
+
+@table @option
+@item size, s
+Set output video size.
+
+@item x
+Set x offset from where to pick pixels.
+
+@item y
+Set y offset from where to pick pixels.
+
+@item mode
+Set scope mode, can be one of the following:
+@table @samp
+@item mono
+Draw hexadecimal pixel values with white color on black background.
+
+@item color
+Draw hexadecimal pixel values with input video pixel color on black
+background.
+
+@item color2
+Draw hexadecimal pixel values on color background picked from input video,
+the text color is picked in such way so its always visible.
+@end table
+
+@item axis
+Draw rows and columns numbers on left and top of video.
+@end table
+
+@section dctdnoiz
+
+Denoise frames using 2D DCT (frequency domain filtering).
+
+This filter is not designed for real time.
+
+The filter accepts the following options:
+
+@table @option
+@item sigma, s
+Set the noise sigma constant.
+
+This @var{sigma} defines a hard threshold of @code{3 * sigma}; every DCT
+coefficient (absolute value) below this threshold with be dropped.
+
+If you need a more advanced filtering, see @option{expr}.
+
+Default is @code{0}.
+
+@item overlap
+Set number overlapping pixels for each block. Since the filter can be slow, you
+may want to reduce this value, at the cost of a less effective filter and the
+risk of various artefacts.
+
+If the overlapping value doesn't permit processing the whole input width or
+height, a warning will be displayed and according borders won't be denoised.
+
+Default value is @var{blocksize}-1, which is the best possible setting.
+
+@item expr, e
+Set the coefficient factor expression.
+
+For each coefficient of a DCT block, this expression will be evaluated as a
+multiplier value for the coefficient.
+
+If this is option is set, the @option{sigma} option will be ignored.
+
+The absolute value of the coefficient can be accessed through the @var{c}
+variable.
+
+@item n
+Set the @var{blocksize} using the number of bits. @code{1<<@var{n}} defines the
+@var{blocksize}, which is the width and height of the processed blocks.
+
+The default value is @var{3} (8x8) and can be raised to @var{4} for a
+@var{blocksize} of 16x16. Note that changing this setting has huge consequences
+on the speed processing. Also, a larger block size does not necessarily means a
+better de-noising.
+@end table
+
+@subsection Examples
+
+Apply a denoise with a @option{sigma} of @code{4.5}:
+@example
+dctdnoiz=4.5
+@end example
+
+The same operation can be achieved using the expression system:
+@example
+dctdnoiz=e='gte(c, 4.5*3)'
+@end example
+
+Violent denoise using a block size of @code{16x16}:
+@example
+dctdnoiz=15:n=4
+@end example
+
+@section deband
+
+Remove banding artifacts from input video.
+It works by replacing banded pixels with average value of referenced pixels.
+
+The filter accepts the following options:
+
+@table @option
+@item 1thr
+@item 2thr
+@item 3thr
+@item 4thr
+Set banding detection threshold for each plane. Default is 0.02.
+Valid range is 0.00003 to 0.5.
+If difference between current pixel and reference pixel is less than threshold,
+it will be considered as banded.
+
+@item range, r
+Banding detection range in pixels. Default is 16. If positive, random number
+in range 0 to set value will be used. If negative, exact absolute value
+will be used.
+The range defines square of four pixels around current pixel.
+
+@item direction, d
+Set direction in radians from which four pixel will be compared. If positive,
+random direction from 0 to set direction will be picked. If negative, exact of
+absolute value will be picked. For example direction 0, -PI or -2*PI radians
+will pick only pixels on same row and -PI/2 will pick only pixels on same
+column.
+
+@item blur
+If enabled, current pixel is compared with average value of all four
+surrounding pixels. The default is enabled. If disabled current pixel is
+compared with all four surrounding pixels. The pixel is considered banded
+if only all four differences with surrounding pixels are less than threshold.
+@end table
+
+@anchor{decimate}
+@section decimate
+
+Drop duplicated frames at regular intervals.
+
+The filter accepts the following options:
+
+@table @option
+@item cycle
+Set the number of frames from which one will be dropped. Setting this to
+@var{N} means one frame in every batch of @var{N} frames will be dropped.
+Default is @code{5}.
+
+@item dupthresh
+Set the threshold for duplicate detection. If the difference metric for a frame
+is less than or equal to this value, then it is declared as duplicate. Default
+is @code{1.1}
+
+@item scthresh
+Set scene change threshold. Default is @code{15}.
+
+@item blockx
+@item blocky
+Set the size of the x and y-axis blocks used during metric calculations.
+Larger blocks give better noise suppression, but also give worse detection of
+small movements. Must be a power of two. Default is @code{32}.
+
+@item ppsrc
+Mark main input as a pre-processed input and activate clean source input
+stream. This allows the input to be pre-processed with various filters to help
+the metrics calculation while keeping the frame selection lossless. When set to
+@code{1}, the first stream is for the pre-processed input, and the second
+stream is the clean source from where the kept frames are chosen. Default is
+@code{0}.
+
+@item chroma
+Set whether or not chroma is considered in the metric calculations. Default is
+@code{1}.
+@end table
+
+@section deflate
+
+Apply deflate effect to the video.
+
+This filter replaces the pixel by the local(3x3) average by taking into account
+only values lower than the pixel.
+
+It accepts the following options:
+
+@table @option
+@item threshold0
+@item threshold1
+@item threshold2
+@item threshold3
+Limit the maximum change for each plane, default is 65535.
+If 0, plane will remain unchanged.
+@end table
+
+@section dejudder
+
+Remove judder produced by partially interlaced telecined content.
+
+Judder can be introduced, for instance, by @ref{pullup} filter. If the original
+source was partially telecined content then the output of @code{pullup,dejudder}
+will have a variable frame rate. May change the recorded frame rate of the
+container. Aside from that change, this filter will not affect constant frame
+rate video.
+
+The option available in this filter is:
+@table @option
+
+@item cycle
+Specify the length of the window over which the judder repeats.
+
+Accepts any integer greater than 1. Useful values are:
+@table @samp
+
+@item 4
+If the original was telecined from 24 to 30 fps (Film to NTSC).
+
+@item 5
+If the original was telecined from 25 to 30 fps (PAL to NTSC).
+
+@item 20
+If a mixture of the two.
+@end table
+
+The default is @samp{4}.
+@end table
+
+@section delogo
+
+Suppress a TV station logo by a simple interpolation of the surrounding
+pixels. Just set a rectangle covering the logo and watch it disappear
+(and sometimes something even uglier appear - your mileage may vary).
+
+It accepts the following parameters:
+@table @option
+
+@item x
+@item y
+Specify the top left corner coordinates of the logo. They must be
+specified.
+
+@item w
+@item h
+Specify the width and height of the logo to clear. They must be
+specified.
+
+@item band, t
+Specify the thickness of the fuzzy edge of the rectangle (added to
+@var{w} and @var{h}). The default value is 1. This option is
+deprecated, setting higher values should no longer be necessary and
+is not recommended.
+
+@item show
+When set to 1, a green rectangle is drawn on the screen to simplify
+finding the right @var{x}, @var{y}, @var{w}, and @var{h} parameters.
+The default value is 0.
+
+The rectangle is drawn on the outermost pixels which will be (partly)
+replaced with interpolated values. The values of the next pixels
+immediately outside this rectangle in each direction will be used to
+compute the interpolated pixel values inside the rectangle.
+
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Set a rectangle covering the area with top left corner coordinates 0,0
+and size 100x77, and a band of size 10:
+@example
+delogo=x=0:y=0:w=100:h=77:band=10
+@end example
+
+@end itemize
+
+@section deshake
+
+Attempt to fix small changes in horizontal and/or vertical shift. This
+filter helps remove camera shake from hand-holding a camera, bumping a
+tripod, moving on a vehicle, etc.
+
+The filter accepts the following options:
+
+@table @option
+
+@item x
+@item y
+@item w
+@item h
+Specify a rectangular area where to limit the search for motion
+vectors.
+If desired the search for motion vectors can be limited to a
+rectangular area of the frame defined by its top left corner, width
+and height. These parameters have the same meaning as the drawbox
+filter which can be used to visualise the position of the bounding
+box.
+
+This is useful when simultaneous movement of subjects within the frame
+might be confused for camera motion by the motion vector search.
+
+If any or all of @var{x}, @var{y}, @var{w} and @var{h} are set to -1
+then the full frame is used. This allows later options to be set
+without specifying the bounding box for the motion vector search.
+
+Default - search the whole frame.
+
+@item rx
+@item ry
+Specify the maximum extent of movement in x and y directions in the
+range 0-64 pixels. Default 16.
+
+@item edge
+Specify how to generate pixels to fill blanks at the edge of the
+frame. Available values are:
+@table @samp
+@item blank, 0
+Fill zeroes at blank locations
+@item original, 1
+Original image at blank locations
+@item clamp, 2
+Extruded edge value at blank locations
+@item mirror, 3
+Mirrored edge at blank locations
+@end table
+Default value is @samp{mirror}.
+
+@item blocksize
+Specify the blocksize to use for motion search. Range 4-128 pixels,
+default 8.
+
+@item contrast
+Specify the contrast threshold for blocks. Only blocks with more than
+the specified contrast (difference between darkest and lightest
+pixels) will be considered. Range 1-255, default 125.
+
+@item search
+Specify the search strategy. Available values are:
+@table @samp
+@item exhaustive, 0
+Set exhaustive search
+@item less, 1
+Set less exhaustive search.
+@end table
+Default value is @samp{exhaustive}.
+
+@item filename
+If set then a detailed log of the motion search is written to the
+specified file.
+
+@item opencl
+If set to 1, specify using OpenCL capabilities, only available if
+FFmpeg was configured with @code{--enable-opencl}. Default value is 0.
+
+@end table
+
+@section detelecine
+
+Apply an exact inverse of the telecine operation. It requires a predefined
+pattern specified using the pattern option which must be the same as that passed
+to the telecine filter.
+
+This filter accepts the following options:
+
+@table @option
+@item first_field
+@table @samp
+@item top, t
+top field first
+@item bottom, b
+bottom field first
+The default value is @code{top}.
+@end table
+
+@item pattern
+A string of numbers representing the pulldown pattern you wish to apply.
+The default value is @code{23}.
+
+@item start_frame
+A number representing position of the first frame with respect to the telecine
+pattern. This is to be used if the stream is cut. The default value is @code{0}.
+@end table
+
+@section dilation
+
+Apply dilation effect to the video.
+
+This filter replaces the pixel by the local(3x3) maximum.
+
+It accepts the following options:
+
+@table @option
+@item threshold0
+@item threshold1
+@item threshold2
+@item threshold3
+Limit the maximum change for each plane, default is 65535.
+If 0, plane will remain unchanged.
+
+@item coordinates
+Flag which specifies the pixel to refer to. Default is 255 i.e. all eight
+pixels are used.
+
+Flags to local 3x3 coordinates maps like this:
+
+ 1 2 3
+ 4 5
+ 6 7 8
+@end table
+
+@section displace
+
+Displace pixels as indicated by second and third input stream.
+
+It takes three input streams and outputs one stream, the first input is the
+source, and second and third input are displacement maps.
+
+The second input specifies how much to displace pixels along the
+x-axis, while the third input specifies how much to displace pixels
+along the y-axis.
+If one of displacement map streams terminates, last frame from that
+displacement map will be used.
+
+Note that once generated, displacements maps can be reused over and over again.
+
+A description of the accepted options follows.
+
+@table @option
+@item edge
+Set displace behavior for pixels that are out of range.
+
+Available values are:
+@table @samp
+@item blank
+Missing pixels are replaced by black pixels.
+
+@item smear
+Adjacent pixels will spread out to replace missing pixels.
+
+@item wrap
+Out of range pixels are wrapped so they point to pixels of other side.
+@end table
+Default is @samp{smear}.
+
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Add ripple effect to rgb input of video size hd720:
+@example
+ffmpeg -i INPUT -f lavfi -i nullsrc=s=hd720,lutrgb=128:128:128 -f lavfi -i nullsrc=s=hd720,geq='r=128+30*sin(2*PI*X/400+T):g=128+30*sin(2*PI*X/400+T):b=128+30*sin(2*PI*X/400+T)' -lavfi '[0][1][2]displace' OUTPUT
+@end example
+
+@item
+Add wave effect to rgb input of video size hd720:
+@example
+ffmpeg -i INPUT -f lavfi -i nullsrc=hd720,geq='r=128+80*(sin(sqrt((X-W/2)*(X-W/2)+(Y-H/2)*(Y-H/2))/220*2*PI+T)):g=128+80*(sin(sqrt((X-W/2)*(X-W/2)+(Y-H/2)*(Y-H/2))/220*2*PI+T)):b=128+80*(sin(sqrt((X-W/2)*(X-W/2)+(Y-H/2)*(Y-H/2))/220*2*PI+T))' -lavfi '[1]split[x][y],[0][x][y]displace' OUTPUT
+@end example
+@end itemize
+
+@section drawbox
+
+Draw a colored box on the input image.
+
+It accepts the following parameters:
+
+@table @option
+@item x
+@item y
+The expressions which specify the top left corner coordinates of the box. It defaults to 0.
+
+@item width, w
+@item height, h
+The expressions which specify the width and height of the box; if 0 they are interpreted as
+the input width and height. It defaults to 0.
+
+@item color, c
+Specify the color of the box to write. For the general syntax of this option,
+check the "Color" section in the ffmpeg-utils manual. If the special
+value @code{invert} is used, the box edge color is the same as the
+video with inverted luma.
+
+@item thickness, t
+The expression which sets the thickness of the box edge. Default value is @code{3}.
+
+See below for the list of accepted constants.
+@end table
+
+The parameters for @var{x}, @var{y}, @var{w} and @var{h} and @var{t} are expressions containing the
+following constants:
+
+@table @option
+@item dar
+The input display aspect ratio, it is the same as (@var{w} / @var{h}) * @var{sar}.
+
+@item hsub
+@item vsub
+horizontal and vertical chroma subsample values. For example for the
+pixel format "yuv422p" @var{hsub} is 2 and @var{vsub} is 1.
+
+@item in_h, ih
+@item in_w, iw
+The input width and height.
+
+@item sar
+The input sample aspect ratio.
+
+@item x
+@item y
+The x and y offset coordinates where the box is drawn.
+
+@item w
+@item h
+The width and height of the drawn box.
+
+@item t
+The thickness of the drawn box.
+
+These constants allow the @var{x}, @var{y}, @var{w}, @var{h} and @var{t} expressions to refer to
+each other, so you may for example specify @code{y=x/dar} or @code{h=w/dar}.
+
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Draw a black box around the edge of the input image:
+@example
+drawbox
+@end example
+
+@item
+Draw a box with color red and an opacity of 50%:
+@example
+drawbox=10:20:200:60:red@@0.5
+@end example
+
+The previous example can be specified as:
+@example
+drawbox=x=10:y=20:w=200:h=60:color=red@@0.5
+@end example
+
+@item
+Fill the box with pink color:
+@example
+drawbox=x=10:y=10:w=100:h=100:color=pink@@0.5:t=max
+@end example
+
+@item
+Draw a 2-pixel red 2.40:1 mask:
+@example
+drawbox=x=-t:y=0.5*(ih-iw/2.4)-t:w=iw+t*2:h=iw/2.4+t*2:t=2:c=red
+@end example
+@end itemize
+
+@section drawgraph, adrawgraph
+
+Draw a graph using input video or audio metadata.
+
+It accepts the following parameters:
+
+@table @option
+@item m1
+Set 1st frame metadata key from which metadata values will be used to draw a graph.
+
+@item fg1
+Set 1st foreground color expression.
+
+@item m2
+Set 2nd frame metadata key from which metadata values will be used to draw a graph.
+
+@item fg2
+Set 2nd foreground color expression.
+
+@item m3
+Set 3rd frame metadata key from which metadata values will be used to draw a graph.
+
+@item fg3
+Set 3rd foreground color expression.
+
+@item m4
+Set 4th frame metadata key from which metadata values will be used to draw a graph.
+
+@item fg4
+Set 4th foreground color expression.
+
+@item min
+Set minimal value of metadata value.
+
+@item max
+Set maximal value of metadata value.
+
+@item bg
+Set graph background color. Default is white.
+
+@item mode
+Set graph mode.
+
+Available values for mode is:
+@table @samp
+@item bar
+@item dot
+@item line
+@end table
+
+Default is @code{line}.
+
+@item slide
+Set slide mode.
+
+Available values for slide is:
+@table @samp
+@item frame
+Draw new frame when right border is reached.
+
+@item replace
+Replace old columns with new ones.
+
+@item scroll
+Scroll from right to left.
+
+@item rscroll
+Scroll from left to right.
+@end table
+
+Default is @code{frame}.
+
+@item size
+Set size of graph video. For the syntax of this option, check the
+@ref{video size syntax,,"Video size" section in the ffmpeg-utils manual,ffmpeg-utils}.
+The default value is @code{900x256}.
+
+The foreground color expressions can use the following variables:
+@table @option
+@item MIN
+Minimal value of metadata value.
+
+@item MAX
+Maximal value of metadata value.
+
+@item VAL
+Current metadata key value.
+@end table
+
+The color is defined as 0xAABBGGRR.
+@end table
+
+Example using metadata from @ref{signalstats} filter:
+@example
+signalstats,drawgraph=lavfi.signalstats.YAVG:min=0:max=255
+@end example
+
+Example using metadata from @ref{ebur128} filter:
+@example
+ebur128=metadata=1,adrawgraph=lavfi.r128.M:min=-120:max=5
+@end example
+
+@section drawgrid
+
+Draw a grid on the input image.
+
+It accepts the following parameters:
+
+@table @option
+@item x
+@item y
+The expressions which specify the coordinates of some point of grid intersection (meant to configure offset). Both default to 0.
+
+@item width, w
+@item height, h
+The expressions which specify the width and height of the grid cell, if 0 they are interpreted as the
+input width and height, respectively, minus @code{thickness}, so image gets
+framed. Default to 0.
+
+@item color, c
+Specify the color of the grid. For the general syntax of this option,
+check the "Color" section in the ffmpeg-utils manual. If the special
+value @code{invert} is used, the grid color is the same as the
+video with inverted luma.
+
+@item thickness, t
+The expression which sets the thickness of the grid line. Default value is @code{1}.
+
+See below for the list of accepted constants.
+@end table
+
+The parameters for @var{x}, @var{y}, @var{w} and @var{h} and @var{t} are expressions containing the
+following constants:
+
+@table @option
+@item dar
+The input display aspect ratio, it is the same as (@var{w} / @var{h}) * @var{sar}.
+
+@item hsub
+@item vsub
+horizontal and vertical chroma subsample values. For example for the
+pixel format "yuv422p" @var{hsub} is 2 and @var{vsub} is 1.
+
+@item in_h, ih
+@item in_w, iw
+The input grid cell width and height.
+
+@item sar
+The input sample aspect ratio.
+
+@item x
+@item y
+The x and y coordinates of some point of grid intersection (meant to configure offset).
+
+@item w
+@item h
+The width and height of the drawn cell.
+
+@item t
+The thickness of the drawn cell.
+
+These constants allow the @var{x}, @var{y}, @var{w}, @var{h} and @var{t} expressions to refer to
+each other, so you may for example specify @code{y=x/dar} or @code{h=w/dar}.
+
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Draw a grid with cell 100x100 pixels, thickness 2 pixels, with color red and an opacity of 50%:
+@example
+drawgrid=width=100:height=100:thickness=2:color=red@@0.5
+@end example
+
+@item
+Draw a white 3x3 grid with an opacity of 50%:
+@example
+drawgrid=w=iw/3:h=ih/3:t=2:c=white@@0.5
+@end example
+@end itemize
+
+@anchor{drawtext}
+@section drawtext
+
+Draw a text string or text from a specified file on top of a video, using the
+libfreetype library.
+
+To enable compilation of this filter, you need to configure FFmpeg with
+@code{--enable-libfreetype}.
+To enable default font fallback and the @var{font} option you need to
+configure FFmpeg with @code{--enable-libfontconfig}.
+To enable the @var{text_shaping} option, you need to configure FFmpeg with
+@code{--enable-libfribidi}.
+
+@subsection Syntax
+
+It accepts the following parameters:
+
+@table @option
+
+@item box
+Used to draw a box around text using the background color.
+The value must be either 1 (enable) or 0 (disable).
+The default value of @var{box} is 0.
+
+@item boxborderw
+Set the width of the border to be drawn around the box using @var{boxcolor}.
+The default value of @var{boxborderw} is 0.
+
+@item boxcolor
+The color to be used for drawing box around text. For the syntax of this
+option, check the "Color" section in the ffmpeg-utils manual.
+
+The default value of @var{boxcolor} is "white".
+
+@item borderw
+Set the width of the border to be drawn around the text using @var{bordercolor}.
+The default value of @var{borderw} is 0.
+
+@item bordercolor
+Set the color to be used for drawing border around text. For the syntax of this
+option, check the "Color" section in the ffmpeg-utils manual.
+
+The default value of @var{bordercolor} is "black".
+
+@item expansion
+Select how the @var{text} is expanded. Can be either @code{none},
+@code{strftime} (deprecated) or
+@code{normal} (default). See the @ref{drawtext_expansion, Text expansion} section
+below for details.
+
+@item fix_bounds
+If true, check and fix text coords to avoid clipping.
+
+@item fontcolor
+The color to be used for drawing fonts. For the syntax of this option, check
+the "Color" section in the ffmpeg-utils manual.
+
+The default value of @var{fontcolor} is "black".
+
+@item fontcolor_expr
+String which is expanded the same way as @var{text} to obtain dynamic
+@var{fontcolor} value. By default this option has empty value and is not
+processed. When this option is set, it overrides @var{fontcolor} option.
+
+@item font
+The font family to be used for drawing text. By default Sans.
+
+@item fontfile
+The font file to be used for drawing text. The path must be included.
+This parameter is mandatory if the fontconfig support is disabled.
+
+@item draw
+This option does not exist, please see the timeline system
+
+@item alpha
+Draw the text applying alpha blending. The value can
+be either a number between 0.0 and 1.0
+The expression accepts the same variables @var{x, y} do.
+The default value is 1.
+Please see fontcolor_expr
+
+@item fontsize
+The font size to be used for drawing text.
+The default value of @var{fontsize} is 16.
+
+@item text_shaping
+If set to 1, attempt to shape the text (for example, reverse the order of
+right-to-left text and join Arabic characters) before drawing it.
+Otherwise, just draw the text exactly as given.
+By default 1 (if supported).
+
+@item ft_load_flags
+The flags to be used for loading the fonts.
+
+The flags map the corresponding flags supported by libfreetype, and are
+a combination of the following values:
+@table @var
+@item default
+@item no_scale
+@item no_hinting
+@item render
+@item no_bitmap
+@item vertical_layout
+@item force_autohint
+@item crop_bitmap
+@item pedantic
+@item ignore_global_advance_width
+@item no_recurse
+@item ignore_transform
+@item monochrome
+@item linear_design
+@item no_autohint
+@end table
+
+Default value is "default".
+
+For more information consult the documentation for the FT_LOAD_*
+libfreetype flags.
+
+@item shadowcolor
+The color to be used for drawing a shadow behind the drawn text. For the
+syntax of this option, check the "Color" section in the ffmpeg-utils manual.
+
+The default value of @var{shadowcolor} is "black".
+
+@item shadowx
+@item shadowy
+The x and y offsets for the text shadow position with respect to the
+position of the text. They can be either positive or negative
+values. The default value for both is "0".
+
+@item start_number
+The starting frame number for the n/frame_num variable. The default value
+is "0".
+
+@item tabsize
+The size in number of spaces to use for rendering the tab.
+Default value is 4.
+
+@item timecode
+Set the initial timecode representation in "hh:mm:ss[:;.]ff"
+format. It can be used with or without text parameter. @var{timecode_rate}
+option must be specified.
+
+@item timecode_rate, rate, r
+Set the timecode frame rate (timecode only).
+
+@item text
+The text string to be drawn. The text must be a sequence of UTF-8
+encoded characters.
+This parameter is mandatory if no file is specified with the parameter
+@var{textfile}.
+
+@item textfile
+A text file containing text to be drawn. The text must be a sequence
+of UTF-8 encoded characters.
+
+This parameter is mandatory if no text string is specified with the
+parameter @var{text}.
+
+If both @var{text} and @var{textfile} are specified, an error is thrown.
+
+@item reload
+If set to 1, the @var{textfile} will be reloaded before each frame.
+Be sure to update it atomically, or it may be read partially, or even fail.
+
+@item x
+@item y
+The expressions which specify the offsets where text will be drawn
+within the video frame. They are relative to the top/left border of the
+output image.
+
+The default value of @var{x} and @var{y} is "0".
+
+See below for the list of accepted constants and functions.
+@end table
+
+The parameters for @var{x} and @var{y} are expressions containing the
+following constants and functions:
+
+@table @option
+@item dar
+input display aspect ratio, it is the same as (@var{w} / @var{h}) * @var{sar}
+
+@item hsub
+@item vsub
+horizontal and vertical chroma subsample values. For example for the
+pixel format "yuv422p" @var{hsub} is 2 and @var{vsub} is 1.
+
+@item line_h, lh
+the height of each text line
+
+@item main_h, h, H
+the input height
+
+@item main_w, w, W
+the input width
+
+@item max_glyph_a, ascent
+the maximum distance from the baseline to the highest/upper grid
+coordinate used to place a glyph outline point, for all the rendered
+glyphs.
+It is a positive value, due to the grid's orientation with the Y axis
+upwards.
+
+@item max_glyph_d, descent
+the maximum distance from the baseline to the lowest grid coordinate
+used to place a glyph outline point, for all the rendered glyphs.
+This is a negative value, due to the grid's orientation, with the Y axis
+upwards.
+
+@item max_glyph_h
+maximum glyph height, that is the maximum height for all the glyphs
+contained in the rendered text, it is equivalent to @var{ascent} -
+@var{descent}.
+
+@item max_glyph_w
+maximum glyph width, that is the maximum width for all the glyphs
+contained in the rendered text
+
+@item n
+the number of input frame, starting from 0
+
+@item rand(min, max)
+return a random number included between @var{min} and @var{max}
+
+@item sar
+The input sample aspect ratio.
+
+@item t
+timestamp expressed in seconds, NAN if the input timestamp is unknown
+
+@item text_h, th
+the height of the rendered text
+
+@item text_w, tw
+the width of the rendered text
+
+@item x
+@item y
+the x and y offset coordinates where the text is drawn.
+
+These parameters allow the @var{x} and @var{y} expressions to refer
+each other, so you can for example specify @code{y=x/dar}.
+@end table
+
+@anchor{drawtext_expansion}
+@subsection Text expansion
+
+If @option{expansion} is set to @code{strftime},
+the filter recognizes strftime() sequences in the provided text and
+expands them accordingly. Check the documentation of strftime(). This
+feature is deprecated.
+
+If @option{expansion} is set to @code{none}, the text is printed verbatim.
+
+If @option{expansion} is set to @code{normal} (which is the default),
+the following expansion mechanism is used.
+
+The backslash character @samp{\}, followed by any character, always expands to
+the second character.
+
+Sequence of the form @code{%@{...@}} are expanded. The text between the
+braces is a function name, possibly followed by arguments separated by ':'.
+If the arguments contain special characters or delimiters (':' or '@}'),
+they should be escaped.
+
+Note that they probably must also be escaped as the value for the
+@option{text} option in the filter argument string and as the filter
+argument in the filtergraph description, and possibly also for the shell,
+that makes up to four levels of escaping; using a text file avoids these
+problems.
+
+The following functions are available:
+
+@table @command
+
+@item expr, e
+The expression evaluation result.
+
+It must take one argument specifying the expression to be evaluated,
+which accepts the same constants and functions as the @var{x} and
+@var{y} values. Note that not all constants should be used, for
+example the text size is not known when evaluating the expression, so
+the constants @var{text_w} and @var{text_h} will have an undefined
+value.
+
+@item expr_int_format, eif
+Evaluate the expression's value and output as formatted integer.
+
+The first argument is the expression to be evaluated, just as for the @var{expr} function.
+The second argument specifies the output format. Allowed values are @samp{x},
+@samp{X}, @samp{d} and @samp{u}. They are treated exactly as in the
+@code{printf} function.
+The third parameter is optional and sets the number of positions taken by the output.
+It can be used to add padding with zeros from the left.
+
+@item gmtime
+The time at which the filter is running, expressed in UTC.
+It can accept an argument: a strftime() format string.
+
+@item localtime
+The time at which the filter is running, expressed in the local time zone.
+It can accept an argument: a strftime() format string.
+
+@item metadata
+Frame metadata. Takes one or two arguments.
+
+The first argument is mandatory and specifies the metadata key.
+
+The second argument is optional and specifies a default value, used when the
+metadata key is not found or empty.
+
+@item n, frame_num
+The frame number, starting from 0.
+
+@item pict_type
+A 1 character description of the current picture type.
+
+@item pts
+The timestamp of the current frame.
+It can take up to three arguments.
+
+The first argument is the format of the timestamp; it defaults to @code{flt}
+for seconds as a decimal number with microsecond accuracy; @code{hms} stands
+for a formatted @var{[-]HH:MM:SS.mmm} timestamp with millisecond accuracy.
+@code{gmtime} stands for the timestamp of the frame formatted as UTC time;
+@code{localtime} stands for the timestamp of the frame formatted as
+local time zone time.
+
+The second argument is an offset added to the timestamp.
+
+If the format is set to @code{localtime} or @code{gmtime},
+a third argument may be supplied: a strftime() format string.
+By default, @var{YYYY-MM-DD HH:MM:SS} format will be used.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Draw "Test Text" with font FreeSerif, using the default values for the
+optional parameters.
+
+@example
+drawtext="fontfile=/usr/share/fonts/truetype/freefont/FreeSerif.ttf: text='Test Text'"
+@end example
+
+@item
+Draw 'Test Text' with font FreeSerif of size 24 at position x=100
+and y=50 (counting from the top-left corner of the screen), text is
+yellow with a red box around it. Both the text and the box have an
+opacity of 20%.
+
+@example
+drawtext="fontfile=/usr/share/fonts/truetype/freefont/FreeSerif.ttf: text='Test Text':\
+ x=100: y=50: fontsize=24: fontcolor=yellow@@0.2: box=1: boxcolor=red@@0.2"
+@end example
+
+Note that the double quotes are not necessary if spaces are not used
+within the parameter list.
+
+@item
+Show the text at the center of the video frame:
+@example
+drawtext="fontsize=30:fontfile=FreeSerif.ttf:text='hello world':x=(w-text_w)/2:y=(h-text_h)/2"
+@end example
+
+@item
+Show the text at a random position, switching to a new position every 30 seconds:
+@example
+drawtext="fontsize=30:fontfile=FreeSerif.ttf:text='hello world':x=if(eq(mod(t\,30)\,0)\,rand(0\,(w-text_w))\,x):y=if(eq(mod(t\,30)\,0)\,rand(0\,(h-text_h))\,y)"
+@end example
+
+@item
+Show a text line sliding from right to left in the last row of the video
+frame. The file @file{LONG_LINE} is assumed to contain a single line
+with no newlines.
+@example
+drawtext="fontsize=15:fontfile=FreeSerif.ttf:text=LONG_LINE:y=h-line_h:x=-50*t"
+@end example
+
+@item
+Show the content of file @file{CREDITS} off the bottom of the frame and scroll up.
+@example
+drawtext="fontsize=20:fontfile=FreeSerif.ttf:textfile=CREDITS:y=h-20*t"
+@end example
+
+@item
+Draw a single green letter "g", at the center of the input video.
+The glyph baseline is placed at half screen height.
+@example
+drawtext="fontsize=60:fontfile=FreeSerif.ttf:fontcolor=green:text=g:x=(w-max_glyph_w)/2:y=h/2-ascent"
+@end example
+
+@item
+Show text for 1 second every 3 seconds:
+@example
+drawtext="fontfile=FreeSerif.ttf:fontcolor=white:x=100:y=x/dar:enable=lt(mod(t\,3)\,1):text='blink'"
+@end example
+
+@item
+Use fontconfig to set the font. Note that the colons need to be escaped.
+@example
+drawtext='fontfile=Linux Libertine O-40\:style=Semibold:text=FFmpeg'
+@end example
+
+@item
+Print the date of a real-time encoding (see strftime(3)):
+@example
+drawtext='fontfile=FreeSans.ttf:text=%@{localtime\:%a %b %d %Y@}'
+@end example
+
+@item
+Show text fading in and out (appearing/disappearing):
+@example
+#!/bin/sh
+DS=1.0 # display start
+DE=10.0 # display end
+FID=1.5 # fade in duration
+FOD=5 # fade out duration
+ffplay -f lavfi "color,drawtext=text=TEST:fontsize=50:fontfile=FreeSerif.ttf:fontcolor_expr=ff0000%@{eif\\\\: clip(255*(1*between(t\\, $DS + $FID\\, $DE - $FOD) + ((t - $DS)/$FID)*between(t\\, $DS\\, $DS + $FID) + (-(t - $DE)/$FOD)*between(t\\, $DE - $FOD\\, $DE) )\\, 0\\, 255) \\\\: x\\\\: 2 @}"
+@end example
+
+@end itemize
+
+For more information about libfreetype, check:
+@url{http://www.freetype.org/}.
+
+For more information about fontconfig, check:
+@url{http://freedesktop.org/software/fontconfig/fontconfig-user.html}.
+
+For more information about libfribidi, check:
+@url{http://fribidi.org/}.
+
+@section edgedetect
+
+Detect and draw edges. The filter uses the Canny Edge Detection algorithm.
+
+The filter accepts the following options:
+
+@table @option
+@item low
+@item high
+Set low and high threshold values used by the Canny thresholding
+algorithm.
+
+The high threshold selects the "strong" edge pixels, which are then
+connected through 8-connectivity with the "weak" edge pixels selected
+by the low threshold.
+
+@var{low} and @var{high} threshold values must be chosen in the range
+[0,1], and @var{low} should be lesser or equal to @var{high}.
+
+Default value for @var{low} is @code{20/255}, and default value for @var{high}
+is @code{50/255}.
+
+@item mode
+Define the drawing mode.
+
+@table @samp
+@item wires
+Draw white/gray wires on black background.
+
+@item colormix
+Mix the colors to create a paint/cartoon effect.
+@end table
+
+Default value is @var{wires}.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Standard edge detection with custom values for the hysteresis thresholding:
+@example
+edgedetect=low=0.1:high=0.4
+@end example
+
+@item
+Painting effect without thresholding:
+@example
+edgedetect=mode=colormix:high=0
+@end example
+@end itemize
+
+@section eq
+Set brightness, contrast, saturation and approximate gamma adjustment.
+
+The filter accepts the following options:
+
+@table @option
+@item contrast
+Set the contrast expression. The value must be a float value in range
+@code{-2.0} to @code{2.0}. The default value is "1".
+
+@item brightness
+Set the brightness expression. The value must be a float value in
+range @code{-1.0} to @code{1.0}. The default value is "0".
+
+@item saturation
+Set the saturation expression. The value must be a float in
+range @code{0.0} to @code{3.0}. The default value is "1".
+
+@item gamma
+Set the gamma expression. The value must be a float in range
+@code{0.1} to @code{10.0}. The default value is "1".
+
+@item gamma_r
+Set the gamma expression for red. The value must be a float in
+range @code{0.1} to @code{10.0}. The default value is "1".
+
+@item gamma_g
+Set the gamma expression for green. The value must be a float in range
+@code{0.1} to @code{10.0}. The default value is "1".
+
+@item gamma_b
+Set the gamma expression for blue. The value must be a float in range
+@code{0.1} to @code{10.0}. The default value is "1".
+
+@item gamma_weight
+Set the gamma weight expression. It can be used to reduce the effect
+of a high gamma value on bright image areas, e.g. keep them from
+getting overamplified and just plain white. The value must be a float
+in range @code{0.0} to @code{1.0}. A value of @code{0.0} turns the
+gamma correction all the way down while @code{1.0} leaves it at its
+full strength. Default is "1".
+
+@item eval
+Set when the expressions for brightness, contrast, saturation and
+gamma expressions are evaluated.
+
+It accepts the following values:
+@table @samp
+@item init
+only evaluate expressions once during the filter initialization or
+when a command is processed
+
+@item frame
+evaluate expressions for each incoming frame
+@end table
+
+Default value is @samp{init}.
+@end table
+
+The expressions accept the following parameters:
+@table @option
+@item n
+frame count of the input frame starting from 0
+
+@item pos
+byte position of the corresponding packet in the input file, NAN if
+unspecified
+
+@item r
+frame rate of the input video, NAN if the input frame rate is unknown
+
+@item t
+timestamp expressed in seconds, NAN if the input timestamp is unknown
+@end table
+
+@subsection Commands
+The filter supports the following commands:
+
+@table @option
+@item contrast
+Set the contrast expression.
+
+@item brightness
+Set the brightness expression.
+
+@item saturation
+Set the saturation expression.
+
+@item gamma
+Set the gamma expression.
+
+@item gamma_r
+Set the gamma_r expression.
+
+@item gamma_g
+Set gamma_g expression.
+
+@item gamma_b
+Set gamma_b expression.
+
+@item gamma_weight
+Set gamma_weight expression.
+
+The command accepts the same syntax of the corresponding option.
+
+If the specified expression is not valid, it is kept at its current
+value.
+
+@end table
+
+@section erosion
+
+Apply erosion effect to the video.
+
+This filter replaces the pixel by the local(3x3) minimum.
+
+It accepts the following options:
+
+@table @option
+@item threshold0
+@item threshold1
+@item threshold2
+@item threshold3
+Limit the maximum change for each plane, default is 65535.
+If 0, plane will remain unchanged.
+
+@item coordinates
+Flag which specifies the pixel to refer to. Default is 255 i.e. all eight
+pixels are used.
+
+Flags to local 3x3 coordinates maps like this:
+
+ 1 2 3
+ 4 5
+ 6 7 8
+@end table
+
+@section extractplanes
+
+Extract color channel components from input video stream into
+separate grayscale video streams.
+
+The filter accepts the following option:
+
+@table @option
+@item planes
+Set plane(s) to extract.
+
+Available values for planes are:
+@table @samp
+@item y
+@item u
+@item v
+@item a
+@item r
+@item g
+@item b
+@end table
+
+Choosing planes not available in the input will result in an error.
+That means you cannot select @code{r}, @code{g}, @code{b} planes
+with @code{y}, @code{u}, @code{v} planes at same time.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Extract luma, u and v color channel component from input video frame
+into 3 grayscale outputs:
+@example
+ffmpeg -i video.avi -filter_complex 'extractplanes=y+u+v[y][u][v]' -map '[y]' y.avi -map '[u]' u.avi -map '[v]' v.avi
+@end example
+@end itemize
+
+@section elbg
+
+Apply a posterize effect using the ELBG (Enhanced LBG) algorithm.
+
+For each input image, the filter will compute the optimal mapping from
+the input to the output given the codebook length, that is the number
+of distinct output colors.
+
+This filter accepts the following options.
+
+@table @option
+@item codebook_length, l
+Set codebook length. The value must be a positive integer, and
+represents the number of distinct output colors. Default value is 256.
+
+@item nb_steps, n
+Set the maximum number of iterations to apply for computing the optimal
+mapping. The higher the value the better the result and the higher the
+computation time. Default value is 1.
+
+@item seed, s
+Set a random seed, must be an integer included between 0 and
+UINT32_MAX. If not specified, or if explicitly set to -1, the filter
+will try to use a good random seed on a best effort basis.
+
+@item pal8
+Set pal8 output pixel format. This option does not work with codebook
+length greater than 256.
+@end table
+
+@section fade
+
+Apply a fade-in/out effect to the input video.
+
+It accepts the following parameters:
+
+@table @option
+@item type, t
+The effect type can be either "in" for a fade-in, or "out" for a fade-out
+effect.
+Default is @code{in}.
+
+@item start_frame, s
+Specify the number of the frame to start applying the fade
+effect at. Default is 0.
+
+@item nb_frames, n
+The number of frames that the fade effect lasts. At the end of the
+fade-in effect, the output video will have the same intensity as the input video.
+At the end of the fade-out transition, the output video will be filled with the
+selected @option{color}.
+Default is 25.
+
+@item alpha
+If set to 1, fade only alpha channel, if one exists on the input.
+Default value is 0.
+
+@item start_time, st
+Specify the timestamp (in seconds) of the frame to start to apply the fade
+effect. If both start_frame and start_time are specified, the fade will start at
+whichever comes last. Default is 0.
+
+@item duration, d
+The number of seconds for which the fade effect has to last. At the end of the
+fade-in effect the output video will have the same intensity as the input video,
+at the end of the fade-out transition the output video will be filled with the
+selected @option{color}.
+If both duration and nb_frames are specified, duration is used. Default is 0
+(nb_frames is used by default).
+
+@item color, c
+Specify the color of the fade. Default is "black".
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Fade in the first 30 frames of video:
+@example
+fade=in:0:30
+@end example
+
+The command above is equivalent to:
+@example
+fade=t=in:s=0:n=30
+@end example
+
+@item
+Fade out the last 45 frames of a 200-frame video:
+@example
+fade=out:155:45
+fade=type=out:start_frame=155:nb_frames=45
+@end example
+
+@item
+Fade in the first 25 frames and fade out the last 25 frames of a 1000-frame video:
+@example
+fade=in:0:25, fade=out:975:25
+@end example
+
+@item
+Make the first 5 frames yellow, then fade in from frame 5-24:
+@example
+fade=in:5:20:color=yellow
+@end example
+
+@item
+Fade in alpha over first 25 frames of video:
+@example
+fade=in:0:25:alpha=1
+@end example
+
+@item
+Make the first 5.5 seconds black, then fade in for 0.5 seconds:
+@example
+fade=t=in:st=5.5:d=0.5
+@end example
+
+@end itemize
+
+@section fftfilt
+Apply arbitrary expressions to samples in frequency domain
+
+@table @option
+@item dc_Y
+Adjust the dc value (gain) of the luma plane of the image. The filter
+accepts an integer value in range @code{0} to @code{1000}. The default
+value is set to @code{0}.
+
+@item dc_U
+Adjust the dc value (gain) of the 1st chroma plane of the image. The
+filter accepts an integer value in range @code{0} to @code{1000}. The
+default value is set to @code{0}.
+
+@item dc_V
+Adjust the dc value (gain) of the 2nd chroma plane of the image. The
+filter accepts an integer value in range @code{0} to @code{1000}. The
+default value is set to @code{0}.
+
+@item weight_Y
+Set the frequency domain weight expression for the luma plane.
+
+@item weight_U
+Set the frequency domain weight expression for the 1st chroma plane.
+
+@item weight_V
+Set the frequency domain weight expression for the 2nd chroma plane.
+
+The filter accepts the following variables:
+@item X
+@item Y
+The coordinates of the current sample.
+
+@item W
+@item H
+The width and height of the image.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+High-pass:
+@example
+fftfilt=dc_Y=128:weight_Y='squish(1-(Y+X)/100)'
+@end example
+
+@item
+Low-pass:
+@example
+fftfilt=dc_Y=0:weight_Y='squish((Y+X)/100-1)'
+@end example
+
+@item
+Sharpen:
+@example
+fftfilt=dc_Y=0:weight_Y='1+squish(1-(Y+X)/100)'
+@end example
+
+@item
+Blur:
+@example
+fftfilt=dc_Y=0:weight_Y='exp(-4 * ((Y+X)/(W+H)))'
+@end example
+
+@end itemize
+
+@section field
+
+Extract a single field from an interlaced image using stride
+arithmetic to avoid wasting CPU time. The output frames are marked as
+non-interlaced.
+
+The filter accepts the following options:
+
+@table @option
+@item type
+Specify whether to extract the top (if the value is @code{0} or
+@code{top}) or the bottom field (if the value is @code{1} or
+@code{bottom}).
+@end table
+
+@section fieldhint
+
+Create new frames by copying the top and bottom fields from surrounding frames
+supplied as numbers by the hint file.
+
+@table @option
+@item hint
+Set file containing hints: absolute/relative frame numbers.
+
+There must be one line for each frame in a clip. Each line must contain two
+numbers separated by the comma, optionally followed by @code{-} or @code{+}.
+Numbers supplied on each line of file can not be out of [N-1,N+1] where N
+is current frame number for @code{absolute} mode or out of [-1, 1] range
+for @code{relative} mode. First number tells from which frame to pick up top
+field and second number tells from which frame to pick up bottom field.
+
+If optionally followed by @code{+} output frame will be marked as interlaced,
+else if followed by @code{-} output frame will be marked as progressive, else
+it will be marked same as input frame.
+If line starts with @code{#} or @code{;} that line is skipped.
+
+@item mode
+Can be item @code{absolute} or @code{relative}. Default is @code{absolute}.
+@end table
+
+Example of first several lines of @code{hint} file for @code{relative} mode:
+@example
+0,0 - # first frame
+1,0 - # second frame, use third's frame top field and second's frame bottom field
+1,0 - # third frame, use fourth's frame top field and third's frame bottom field
+1,0 -
+0,0 -
+0,0 -
+1,0 -
+1,0 -
+1,0 -
+0,0 -
+0,0 -
+1,0 -
+1,0 -
+1,0 -
+0,0 -
+@end example
+
+@section fieldmatch
+
+Field matching filter for inverse telecine. It is meant to reconstruct the
+progressive frames from a telecined stream. The filter does not drop duplicated
+frames, so to achieve a complete inverse telecine @code{fieldmatch} needs to be
+followed by a decimation filter such as @ref{decimate} in the filtergraph.
+
+The separation of the field matching and the decimation is notably motivated by
+the possibility of inserting a de-interlacing filter fallback between the two.
+If the source has mixed telecined and real interlaced content,
+@code{fieldmatch} will not be able to match fields for the interlaced parts.
+But these remaining combed frames will be marked as interlaced, and thus can be
+de-interlaced by a later filter such as @ref{yadif} before decimation.
+
+In addition to the various configuration options, @code{fieldmatch} can take an
+optional second stream, activated through the @option{ppsrc} option. If
+enabled, the frames reconstruction will be based on the fields and frames from
+this second stream. This allows the first input to be pre-processed in order to
+help the various algorithms of the filter, while keeping the output lossless
+(assuming the fields are matched properly). Typically, a field-aware denoiser,
+or brightness/contrast adjustments can help.
+
+Note that this filter uses the same algorithms as TIVTC/TFM (AviSynth project)
+and VIVTC/VFM (VapourSynth project). The later is a light clone of TFM from
+which @code{fieldmatch} is based on. While the semantic and usage are very
+close, some behaviour and options names can differ.
+
+The @ref{decimate} filter currently only works for constant frame rate input.
+If your input has mixed telecined (30fps) and progressive content with a lower
+framerate like 24fps use the following filterchain to produce the necessary cfr
+stream: @code{dejudder,fps=30000/1001,fieldmatch,decimate}.
+
+The filter accepts the following options:
+
+@table @option
+@item order
+Specify the assumed field order of the input stream. Available values are:
+
+@table @samp
+@item auto
+Auto detect parity (use FFmpeg's internal parity value).
+@item bff
+Assume bottom field first.
+@item tff
+Assume top field first.
+@end table
+
+Note that it is sometimes recommended not to trust the parity announced by the
+stream.
+
+Default value is @var{auto}.
+
+@item mode
+Set the matching mode or strategy to use. @option{pc} mode is the safest in the
+sense that it won't risk creating jerkiness due to duplicate frames when
+possible, but if there are bad edits or blended fields it will end up
+outputting combed frames when a good match might actually exist. On the other
+hand, @option{pcn_ub} mode is the most risky in terms of creating jerkiness,
+but will almost always find a good frame if there is one. The other values are
+all somewhere in between @option{pc} and @option{pcn_ub} in terms of risking
+jerkiness and creating duplicate frames versus finding good matches in sections
+with bad edits, orphaned fields, blended fields, etc.
+
+More details about p/c/n/u/b are available in @ref{p/c/n/u/b meaning} section.
+
+Available values are:
+
+@table @samp
+@item pc
+2-way matching (p/c)
+@item pc_n
+2-way matching, and trying 3rd match if still combed (p/c + n)
+@item pc_u
+2-way matching, and trying 3rd match (same order) if still combed (p/c + u)
+@item pc_n_ub
+2-way matching, trying 3rd match if still combed, and trying 4th/5th matches if
+still combed (p/c + n + u/b)
+@item pcn
+3-way matching (p/c/n)
+@item pcn_ub
+3-way matching, and trying 4th/5th matches if all 3 of the original matches are
+detected as combed (p/c/n + u/b)
+@end table
+
+The parenthesis at the end indicate the matches that would be used for that
+mode assuming @option{order}=@var{tff} (and @option{field} on @var{auto} or
+@var{top}).
+
+In terms of speed @option{pc} mode is by far the fastest and @option{pcn_ub} is
+the slowest.
+
+Default value is @var{pc_n}.
+
+@item ppsrc
+Mark the main input stream as a pre-processed input, and enable the secondary
+input stream as the clean source to pick the fields from. See the filter
+introduction for more details. It is similar to the @option{clip2} feature from
+VFM/TFM.
+
+Default value is @code{0} (disabled).
+
+@item field
+Set the field to match from. It is recommended to set this to the same value as
+@option{order} unless you experience matching failures with that setting. In
+certain circumstances changing the field that is used to match from can have a
+large impact on matching performance. Available values are:
+
+@table @samp
+@item auto
+Automatic (same value as @option{order}).
+@item bottom
+Match from the bottom field.
+@item top
+Match from the top field.
+@end table
+
+Default value is @var{auto}.
+
+@item mchroma
+Set whether or not chroma is included during the match comparisons. In most
+cases it is recommended to leave this enabled. You should set this to @code{0}
+only if your clip has bad chroma problems such as heavy rainbowing or other
+artifacts. Setting this to @code{0} could also be used to speed things up at
+the cost of some accuracy.
+
+Default value is @code{1}.
+
+@item y0
+@item y1
+These define an exclusion band which excludes the lines between @option{y0} and
+@option{y1} from being included in the field matching decision. An exclusion
+band can be used to ignore subtitles, a logo, or other things that may
+interfere with the matching. @option{y0} sets the starting scan line and
+@option{y1} sets the ending line; all lines in between @option{y0} and
+@option{y1} (including @option{y0} and @option{y1}) will be ignored. Setting
+@option{y0} and @option{y1} to the same value will disable the feature.
+@option{y0} and @option{y1} defaults to @code{0}.
+
+@item scthresh
+Set the scene change detection threshold as a percentage of maximum change on
+the luma plane. Good values are in the @code{[8.0, 14.0]} range. Scene change
+detection is only relevant in case @option{combmatch}=@var{sc}. The range for
+@option{scthresh} is @code{[0.0, 100.0]}.
+
+Default value is @code{12.0}.
+
+@item combmatch
+When @option{combatch} is not @var{none}, @code{fieldmatch} will take into
+account the combed scores of matches when deciding what match to use as the
+final match. Available values are:
+
+@table @samp
+@item none
+No final matching based on combed scores.
+@item sc
+Combed scores are only used when a scene change is detected.
+@item full
+Use combed scores all the time.
+@end table
+
+Default is @var{sc}.
+
+@item combdbg
+Force @code{fieldmatch} to calculate the combed metrics for certain matches and
+print them. This setting is known as @option{micout} in TFM/VFM vocabulary.
+Available values are:
+
+@table @samp
+@item none
+No forced calculation.
+@item pcn
+Force p/c/n calculations.
+@item pcnub
+Force p/c/n/u/b calculations.
+@end table
+
+Default value is @var{none}.
+
+@item cthresh
+This is the area combing threshold used for combed frame detection. This
+essentially controls how "strong" or "visible" combing must be to be detected.
+Larger values mean combing must be more visible and smaller values mean combing
+can be less visible or strong and still be detected. Valid settings are from
+@code{-1} (every pixel will be detected as combed) to @code{255} (no pixel will
+be detected as combed). This is basically a pixel difference value. A good
+range is @code{[8, 12]}.
+
+Default value is @code{9}.
+
+@item chroma
+Sets whether or not chroma is considered in the combed frame decision. Only
+disable this if your source has chroma problems (rainbowing, etc.) that are
+causing problems for the combed frame detection with chroma enabled. Actually,
+using @option{chroma}=@var{0} is usually more reliable, except for the case
+where there is chroma only combing in the source.
+
+Default value is @code{0}.
+
+@item blockx
+@item blocky
+Respectively set the x-axis and y-axis size of the window used during combed
+frame detection. This has to do with the size of the area in which
+@option{combpel} pixels are required to be detected as combed for a frame to be
+declared combed. See the @option{combpel} parameter description for more info.
+Possible values are any number that is a power of 2 starting at 4 and going up
+to 512.
+
+Default value is @code{16}.
+
+@item combpel
+The number of combed pixels inside any of the @option{blocky} by
+@option{blockx} size blocks on the frame for the frame to be detected as
+combed. While @option{cthresh} controls how "visible" the combing must be, this
+setting controls "how much" combing there must be in any localized area (a
+window defined by the @option{blockx} and @option{blocky} settings) on the
+frame. Minimum value is @code{0} and maximum is @code{blocky x blockx} (at
+which point no frames will ever be detected as combed). This setting is known
+as @option{MI} in TFM/VFM vocabulary.
+
+Default value is @code{80}.
+@end table
+
+@anchor{p/c/n/u/b meaning}
+@subsection p/c/n/u/b meaning
+
+@subsubsection p/c/n
+
+We assume the following telecined stream:
+
+@example
+Top fields: 1 2 2 3 4
+Bottom fields: 1 2 3 4 4
+@end example
+
+The numbers correspond to the progressive frame the fields relate to. Here, the
+first two frames are progressive, the 3rd and 4th are combed, and so on.
+
+When @code{fieldmatch} is configured to run a matching from bottom
+(@option{field}=@var{bottom}) this is how this input stream get transformed:
+
+@example
+Input stream:
+ T 1 2 2 3 4
+ B 1 2 3 4 4 <-- matching reference
+
+Matches: c c n n c
+
+Output stream:
+ T 1 2 3 4 4
+ B 1 2 3 4 4
+@end example
+
+As a result of the field matching, we can see that some frames get duplicated.
+To perform a complete inverse telecine, you need to rely on a decimation filter
+after this operation. See for instance the @ref{decimate} filter.
+
+The same operation now matching from top fields (@option{field}=@var{top})
+looks like this:
+
+@example
+Input stream:
+ T 1 2 2 3 4 <-- matching reference
+ B 1 2 3 4 4
+
+Matches: c c p p c
+
+Output stream:
+ T 1 2 2 3 4
+ B 1 2 2 3 4
+@end example
+
+In these examples, we can see what @var{p}, @var{c} and @var{n} mean;
+basically, they refer to the frame and field of the opposite parity:
+
+@itemize
+@item @var{p} matches the field of the opposite parity in the previous frame
+@item @var{c} matches the field of the opposite parity in the current frame
+@item @var{n} matches the field of the opposite parity in the next frame
+@end itemize
+
+@subsubsection u/b
+
+The @var{u} and @var{b} matching are a bit special in the sense that they match
+from the opposite parity flag. In the following examples, we assume that we are
+currently matching the 2nd frame (Top:2, bottom:2). According to the match, a
+'x' is placed above and below each matched fields.
+
+With bottom matching (@option{field}=@var{bottom}):
+@example
+Match: c p n b u
+
+ x x x x x
+ Top 1 2 2 1 2 2 1 2 2 1 2 2 1 2 2
+ Bottom 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3
+ x x x x x
+
+Output frames:
+ 2 1 2 2 2
+ 2 2 2 1 3
+@end example
+
+With top matching (@option{field}=@var{top}):
+@example
+Match: c p n b u
+
+ x x x x x
+ Top 1 2 2 1 2 2 1 2 2 1 2 2 1 2 2
+ Bottom 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3
+ x x x x x
+
+Output frames:
+ 2 2 2 1 2
+ 2 1 3 2 2
+@end example
+
+@subsection Examples
+
+Simple IVTC of a top field first telecined stream:
+@example
+fieldmatch=order=tff:combmatch=none, decimate
+@end example
+
+Advanced IVTC, with fallback on @ref{yadif} for still combed frames:
+@example
+fieldmatch=order=tff:combmatch=full, yadif=deint=interlaced, decimate
+@end example
+
+@section fieldorder
+
+Transform the field order of the input video.
+
+It accepts the following parameters:
+
+@table @option
+
+@item order
+The output field order. Valid values are @var{tff} for top field first or @var{bff}
+for bottom field first.
+@end table
+
+The default value is @samp{tff}.
+
+The transformation is done by shifting the picture content up or down
+by one line, and filling the remaining line with appropriate picture content.
+This method is consistent with most broadcast field order converters.
+
+If the input video is not flagged as being interlaced, or it is already
+flagged as being of the required output field order, then this filter does
+not alter the incoming video.
+
+It is very useful when converting to or from PAL DV material,
+which is bottom field first.
+
+For example:
+@example
+ffmpeg -i in.vob -vf "fieldorder=bff" out.dv
+@end example
+
+@section fifo, afifo
+
+Buffer input images and send them when they are requested.
+
+It is mainly useful when auto-inserted by the libavfilter
+framework.
+
+It does not take parameters.
+
+@section find_rect
+
+Find a rectangular object
+
+It accepts the following options:
+
+@table @option
+@item object
+Filepath of the object image, needs to be in gray8.
+
+@item threshold
+Detection threshold, default is 0.5.
+
+@item mipmaps
+Number of mipmaps, default is 3.
+
+@item xmin, ymin, xmax, ymax
+Specifies the rectangle in which to search.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Generate a representative palette of a given video using @command{ffmpeg}:
+@example
+ffmpeg -i file.ts -vf find_rect=newref.pgm,cover_rect=cover.jpg:mode=cover new.mkv
+@end example
+@end itemize
+
+@section cover_rect
+
+Cover a rectangular object
+
+It accepts the following options:
+
+@table @option
+@item cover
+Filepath of the optional cover image, needs to be in yuv420.
+
+@item mode
+Set covering mode.
+
+It accepts the following values:
+@table @samp
+@item cover
+cover it by the supplied image
+@item blur
+cover it by interpolating the surrounding pixels
+@end table
+
+Default value is @var{blur}.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Generate a representative palette of a given video using @command{ffmpeg}:
+@example
+ffmpeg -i file.ts -vf find_rect=newref.pgm,cover_rect=cover.jpg:mode=cover new.mkv
+@end example
+@end itemize
+
+@anchor{format}
+@section format
+
+Convert the input video to one of the specified pixel formats.
+Libavfilter will try to pick one that is suitable as input to
+the next filter.
+
+It accepts the following parameters:
+@table @option
+
+@item pix_fmts
+A '|'-separated list of pixel format names, such as
+"pix_fmts=yuv420p|monow|rgb24".
+
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Convert the input video to the @var{yuv420p} format
+@example
+format=pix_fmts=yuv420p
+@end example
+
+Convert the input video to any of the formats in the list
+@example
+format=pix_fmts=yuv420p|yuv444p|yuv410p
+@end example
+@end itemize
+
+@anchor{fps}
+@section fps
+
+Convert the video to specified constant frame rate by duplicating or dropping
+frames as necessary.
+
+It accepts the following parameters:
+@table @option
+
+@item fps
+The desired output frame rate. The default is @code{25}.
+
+@item round
+Rounding method.
+
+Possible values are:
+@table @option
+@item zero
+zero round towards 0
+@item inf
+round away from 0
+@item down
+round towards -infinity
+@item up
+round towards +infinity
+@item near
+round to nearest
+@end table
+The default is @code{near}.
+
+@item start_time
+Assume the first PTS should be the given value, in seconds. This allows for
+padding/trimming at the start of stream. By default, no assumption is made
+about the first frame's expected PTS, so no padding or trimming is done.
+For example, this could be set to 0 to pad the beginning with duplicates of
+the first frame if a video stream starts after the audio stream or to trim any
+frames with a negative PTS.
+
+@end table
+
+Alternatively, the options can be specified as a flat string:
+@var{fps}[:@var{round}].
+
+See also the @ref{setpts} filter.
+
+@subsection Examples
+
+@itemize
+@item
+A typical usage in order to set the fps to 25:
+@example
+fps=fps=25
+@end example
+
+@item
+Sets the fps to 24, using abbreviation and rounding method to round to nearest:
+@example
+fps=fps=film:round=near
+@end example
+@end itemize
+
+@section framepack
+
+Pack two different video streams into a stereoscopic video, setting proper
+metadata on supported codecs. The two views should have the same size and
+framerate and processing will stop when the shorter video ends. Please note
+that you may conveniently adjust view properties with the @ref{scale} and
+@ref{fps} filters.
+
+It accepts the following parameters:
+@table @option
+
+@item format
+The desired packing format. Supported values are:
+
+@table @option
+
+@item sbs
+The views are next to each other (default).
+
+@item tab
+The views are on top of each other.
+
+@item lines
+The views are packed by line.
+
+@item columns
+The views are packed by column.
+
+@item frameseq
+The views are temporally interleaved.
+
+@end table
+
+@end table
+
+Some examples:
+
+@example
+# Convert left and right views into a frame-sequential video
+ffmpeg -i LEFT -i RIGHT -filter_complex framepack=frameseq OUTPUT
+
+# Convert views into a side-by-side video with the same output resolution as the input
+ffmpeg -i LEFT -i RIGHT -filter_complex [0:v]scale=w=iw/2[left],[1:v]scale=w=iw/2[right],[left][right]framepack=sbs OUTPUT
+@end example
+
+@section framerate
+
+Change the frame rate by interpolating new video output frames from the source
+frames.
+
+This filter is not designed to function correctly with interlaced media. If
+you wish to change the frame rate of interlaced media then you are required
+to deinterlace before this filter and re-interlace after this filter.
+
+A description of the accepted options follows.
+
+@table @option
+@item fps
+Specify the output frames per second. This option can also be specified
+as a value alone. The default is @code{50}.
+
+@item interp_start
+Specify the start of a range where the output frame will be created as a
+linear interpolation of two frames. The range is [@code{0}-@code{255}],
+the default is @code{15}.
+
+@item interp_end
+Specify the end of a range where the output frame will be created as a
+linear interpolation of two frames. The range is [@code{0}-@code{255}],
+the default is @code{240}.
+
+@item scene
+Specify the level at which a scene change is detected as a value between
+0 and 100 to indicate a new scene; a low value reflects a low
+probability for the current frame to introduce a new scene, while a higher
+value means the current frame is more likely to be one.
+The default is @code{7}.
+
+@item flags
+Specify flags influencing the filter process.
+
+Available value for @var{flags} is:
+
+@table @option
+@item scene_change_detect, scd
+Enable scene change detection using the value of the option @var{scene}.
+This flag is enabled by default.
+@end table
+@end table
+
+@section framestep
+
+Select one frame every N-th frame.
+
+This filter accepts the following option:
+@table @option
+@item step
+Select frame after every @code{step} frames.
+Allowed values are positive integers higher than 0. Default value is @code{1}.
+@end table
+
+@anchor{frei0r}
+@section frei0r
+
+Apply a frei0r effect to the input video.
+
+To enable the compilation of this filter, you need to install the frei0r
+header and configure FFmpeg with @code{--enable-frei0r}.
+
+It accepts the following parameters:
+
+@table @option
+
+@item filter_name
+The name of the frei0r effect to load. If the environment variable
+@env{FREI0R_PATH} is defined, the frei0r effect is searched for in each of the
+directories specified by the colon-separated list in @env{FREIOR_PATH}.
+Otherwise, the standard frei0r paths are searched, in this order:
+@file{HOME/.frei0r-1/lib/}, @file{/usr/local/lib/frei0r-1/},
+@file{/usr/lib/frei0r-1/}.
+
+@item filter_params
+A '|'-separated list of parameters to pass to the frei0r effect.
+
+@end table
+
+A frei0r effect parameter can be a boolean (its value is either
+"y" or "n"), a double, a color (specified as
+@var{R}/@var{G}/@var{B}, where @var{R}, @var{G}, and @var{B} are floating point
+numbers between 0.0 and 1.0, inclusive) or by a color description specified in the "Color"
+section in the ffmpeg-utils manual), a position (specified as @var{X}/@var{Y}, where
+@var{X} and @var{Y} are floating point numbers) and/or a string.
+
+The number and types of parameters depend on the loaded effect. If an
+effect parameter is not specified, the default value is set.
+
+@subsection Examples
+
+@itemize
+@item
+Apply the distort0r effect, setting the first two double parameters:
+@example
+frei0r=filter_name=distort0r:filter_params=0.5|0.01
+@end example
+
+@item
+Apply the colordistance effect, taking a color as the first parameter:
+@example
+frei0r=colordistance:0.2/0.3/0.4
+frei0r=colordistance:violet
+frei0r=colordistance:0x112233
+@end example
+
+@item
+Apply the perspective effect, specifying the top left and top right image
+positions:
+@example
+frei0r=perspective:0.2/0.2|0.8/0.2
+@end example
+@end itemize
+
+For more information, see
+@url{http://frei0r.dyne.org}
+
+@section fspp
+
+Apply fast and simple postprocessing. It is a faster version of @ref{spp}.
+
+It splits (I)DCT into horizontal/vertical passes. Unlike the simple post-
+processing filter, one of them is performed once per block, not per pixel.
+This allows for much higher speed.
+
+The filter accepts the following options:
+
+@table @option
+@item quality
+Set quality. This option defines the number of levels for averaging. It accepts
+an integer in the range 4-5. Default value is @code{4}.
+
+@item qp
+Force a constant quantization parameter. It accepts an integer in range 0-63.
+If not set, the filter will use the QP from the video stream (if available).
+
+@item strength
+Set filter strength. It accepts an integer in range -15 to 32. Lower values mean
+more details but also more artifacts, while higher values make the image smoother
+but also blurrier. Default value is @code{0} − PSNR optimal.
+
+@item use_bframe_qp
+Enable the use of the QP from the B-Frames if set to @code{1}. Using this
+option may cause flicker since the B-Frames have often larger QP. Default is
+@code{0} (not enabled).
+
+@end table
+
+@section geq
+
+The filter accepts the following options:
+
+@table @option
+@item lum_expr, lum
+Set the luminance expression.
+@item cb_expr, cb
+Set the chrominance blue expression.
+@item cr_expr, cr
+Set the chrominance red expression.
+@item alpha_expr, a
+Set the alpha expression.
+@item red_expr, r
+Set the red expression.
+@item green_expr, g
+Set the green expression.
+@item blue_expr, b
+Set the blue expression.
+@end table
+
+The colorspace is selected according to the specified options. If one
+of the @option{lum_expr}, @option{cb_expr}, or @option{cr_expr}
+options is specified, the filter will automatically select a YCbCr
+colorspace. If one of the @option{red_expr}, @option{green_expr}, or
+@option{blue_expr} options is specified, it will select an RGB
+colorspace.
+
+If one of the chrominance expression is not defined, it falls back on the other
+one. If no alpha expression is specified it will evaluate to opaque value.
+If none of chrominance expressions are specified, they will evaluate
+to the luminance expression.
+
+The expressions can use the following variables and functions:
+
+@table @option
+@item N
+The sequential number of the filtered frame, starting from @code{0}.
+
+@item X
+@item Y
+The coordinates of the current sample.
+
+@item W
+@item H
+The width and height of the image.
+
+@item SW
+@item SH
+Width and height scale depending on the currently filtered plane. It is the
+ratio between the corresponding luma plane number of pixels and the current
+plane ones. E.g. for YUV4:2:0 the values are @code{1,1} for the luma plane, and
+@code{0.5,0.5} for chroma planes.
+
+@item T
+Time of the current frame, expressed in seconds.
+
+@item p(x, y)
+Return the value of the pixel at location (@var{x},@var{y}) of the current
+plane.
+
+@item lum(x, y)
+Return the value of the pixel at location (@var{x},@var{y}) of the luminance
+plane.
+
+@item cb(x, y)
+Return the value of the pixel at location (@var{x},@var{y}) of the
+blue-difference chroma plane. Return 0 if there is no such plane.
+
+@item cr(x, y)
+Return the value of the pixel at location (@var{x},@var{y}) of the
+red-difference chroma plane. Return 0 if there is no such plane.
+
+@item r(x, y)
+@item g(x, y)
+@item b(x, y)
+Return the value of the pixel at location (@var{x},@var{y}) of the
+red/green/blue component. Return 0 if there is no such component.
+
+@item alpha(x, y)
+Return the value of the pixel at location (@var{x},@var{y}) of the alpha
+plane. Return 0 if there is no such plane.
+@end table
+
+For functions, if @var{x} and @var{y} are outside the area, the value will be
+automatically clipped to the closer edge.
+
+@subsection Examples
+
+@itemize
+@item
+Flip the image horizontally:
+@example
+geq=p(W-X\,Y)
+@end example
+
+@item
+Generate a bidimensional sine wave, with angle @code{PI/3} and a
+wavelength of 100 pixels:
+@example
+geq=128 + 100*sin(2*(PI/100)*(cos(PI/3)*(X-50*T) + sin(PI/3)*Y)):128:128
+@end example
+
+@item
+Generate a fancy enigmatic moving light:
+@example
+nullsrc=s=256x256,geq=random(1)/hypot(X-cos(N*0.07)*W/2-W/2\,Y-sin(N*0.09)*H/2-H/2)^2*1000000*sin(N*0.02):128:128
+@end example
+
+@item
+Generate a quick emboss effect:
+@example
+format=gray,geq=lum_expr='(p(X,Y)+(256-p(X-4,Y-4)))/2'
+@end example
+
+@item
+Modify RGB components depending on pixel position:
+@example
+geq=r='X/W*r(X,Y)':g='(1-X/W)*g(X,Y)':b='(H-Y)/H*b(X,Y)'
+@end example
+
+@item
+Create a radial gradient that is the same size as the input (also see
+the @ref{vignette} filter):
+@example
+geq=lum=255*gauss((X/W-0.5)*3)*gauss((Y/H-0.5)*3)/gauss(0)/gauss(0),format=gray
+@end example
+@end itemize
+
+@section gradfun
+
+Fix the banding artifacts that are sometimes introduced into nearly flat
- regions by truncation to 8bit color depth.
++regions by truncation to 8-bit color depth.
+Interpolate the gradients that should go where the bands are, and
+dither them.
+
+It is designed for playback only. Do not use it prior to
+lossy compression, because compression tends to lose the dither and
+bring back the bands.
+
+It accepts the following parameters:
+
+@table @option
+
+@item strength
+The maximum amount by which the filter will change any one pixel. This is also
+the threshold for detecting nearly flat regions. Acceptable values range from
+.51 to 64; the default value is 1.2. Out-of-range values will be clipped to the
+valid range.
+
+@item radius
+The neighborhood to fit the gradient to. A larger radius makes for smoother
+gradients, but also prevents the filter from modifying the pixels near detailed
+regions. Acceptable values are 8-32; the default value is 16. Out-of-range
+values will be clipped to the valid range.
+
+@end table
+
+Alternatively, the options can be specified as a flat string:
+@var{strength}[:@var{radius}]
+
+@subsection Examples
+
+@itemize
+@item
+Apply the filter with a @code{3.5} strength and radius of @code{8}:
+@example
+gradfun=3.5:8
+@end example
+
+@item
+Specify radius, omitting the strength (which will fall-back to the default
+value):
+@example
+gradfun=radius=8
+@end example
+
+@end itemize
+
+@anchor{haldclut}
+@section haldclut
+
+Apply a Hald CLUT to a video stream.
+
+First input is the video stream to process, and second one is the Hald CLUT.
+The Hald CLUT input can be a simple picture or a complete video stream.
+
+The filter accepts the following options:
+
+@table @option
+@item shortest
+Force termination when the shortest input terminates. Default is @code{0}.
+@item repeatlast
+Continue applying the last CLUT after the end of the stream. A value of
+@code{0} disable the filter after the last frame of the CLUT is reached.
+Default is @code{1}.
+@end table
+
+@code{haldclut} also has the same interpolation options as @ref{lut3d} (both
+filters share the same internals).
+
+More information about the Hald CLUT can be found on Eskil Steenberg's website
+(Hald CLUT author) at @url{http://www.quelsolaar.com/technology/clut.html}.
+
+@subsection Workflow examples
+
+@subsubsection Hald CLUT video stream
+
+Generate an identity Hald CLUT stream altered with various effects:
+@example
+ffmpeg -f lavfi -i @ref{haldclutsrc}=8 -vf "hue=H=2*PI*t:s=sin(2*PI*t)+1, curves=cross_process" -t 10 -c:v ffv1 clut.nut
+@end example
+
+Note: make sure you use a lossless codec.
+
+Then use it with @code{haldclut} to apply it on some random stream:
+@example
+ffmpeg -f lavfi -i mandelbrot -i clut.nut -filter_complex '[0][1] haldclut' -t 20 mandelclut.mkv
+@end example
+
+The Hald CLUT will be applied to the 10 first seconds (duration of
+@file{clut.nut}), then the latest picture of that CLUT stream will be applied
+to the remaining frames of the @code{mandelbrot} stream.
+
+@subsubsection Hald CLUT with preview
+
+A Hald CLUT is supposed to be a squared image of @code{Level*Level*Level} by
+@code{Level*Level*Level} pixels. For a given Hald CLUT, FFmpeg will select the
+biggest possible square starting at the top left of the picture. The remaining
+padding pixels (bottom or right) will be ignored. This area can be used to add
+a preview of the Hald CLUT.
+
+Typically, the following generated Hald CLUT will be supported by the
+@code{haldclut} filter:
+
+@example
+ffmpeg -f lavfi -i @ref{haldclutsrc}=8 -vf "
+ pad=iw+320 [padded_clut];
+ smptebars=s=320x256, split [a][b];
+ [padded_clut][a] overlay=W-320:h, curves=color_negative [main];
+ [main][b] overlay=W-320" -frames:v 1 clut.png
+@end example
+
+It contains the original and a preview of the effect of the CLUT: SMPTE color
+bars are displayed on the right-top, and below the same color bars processed by
+the color changes.
+
+Then, the effect of this Hald CLUT can be visualized with:
+@example
+ffplay input.mkv -vf "movie=clut.png, [in] haldclut"
+@end example
+
+@section hdcd
+
+Decodes high definition audio cd data. 16-Bit PCM stream containing hdcd flags
+is converted to 20-bit PCM stream.
+
+@section hflip
+
+Flip the input video horizontally.
+
+For example, to horizontally flip the input video with @command{ffmpeg}:
+@example
+ffmpeg -i in.avi -vf "hflip" out.avi
+@end example
+
+@section histeq
+This filter applies a global color histogram equalization on a
+per-frame basis.
+
+It can be used to correct video that has a compressed range of pixel
+intensities. The filter redistributes the pixel intensities to
+equalize their distribution across the intensity range. It may be
+viewed as an "automatically adjusting contrast filter". This filter is
+useful only for correcting degraded or poorly captured source
+video.
+
+The filter accepts the following options:
+
+@table @option
+@item strength
+Determine the amount of equalization to be applied. As the strength
+is reduced, the distribution of pixel intensities more-and-more
+approaches that of the input frame. The value must be a float number
+in the range [0,1] and defaults to 0.200.
+
+@item intensity
+Set the maximum intensity that can generated and scale the output
+values appropriately. The strength should be set as desired and then
+the intensity can be limited if needed to avoid washing-out. The value
+must be a float number in the range [0,1] and defaults to 0.210.
+
+@item antibanding
+Set the antibanding level. If enabled the filter will randomly vary
+the luminance of output pixels by a small amount to avoid banding of
+the histogram. Possible values are @code{none}, @code{weak} or
+@code{strong}. It defaults to @code{none}.
+@end table
+
+@section histogram
+
+Compute and draw a color distribution histogram for the input video.
+
+The computed histogram is a representation of the color component
+distribution in an image.
+
+Standard histogram displays the color components distribution in an image.
+Displays color graph for each color component. Shows distribution of
+the Y, U, V, A or R, G, B components, depending on input format, in the
+current frame. Below each graph a color component scale meter is shown.
+
+The filter accepts the following options:
+
+@table @option
+@item level_height
+Set height of level. Default value is @code{200}.
+Allowed range is [50, 2048].
+
+@item scale_height
+Set height of color scale. Default value is @code{12}.
+Allowed range is [0, 40].
+
+@item display_mode
+Set display mode.
+It accepts the following values:
+@table @samp
+@item parade
+Per color component graphs are placed below each other.
+
+@item overlay
+Presents information identical to that in the @code{parade}, except
+that the graphs representing color components are superimposed directly
+over one another.
+@end table
+Default is @code{parade}.
+
+@item levels_mode
+Set mode. Can be either @code{linear}, or @code{logarithmic}.
+Default is @code{linear}.
+
+@item components
+Set what color components to display.
+Default is @code{7}.
+@end table
+
+@subsection Examples
+
+@itemize
+
+@item
+Calculate and draw histogram:
+@example
+ffplay -i input -vf histogram
+@end example
+
+@end itemize
+
+@anchor{hqdn3d}
+@section hqdn3d
+
+This is a high precision/quality 3d denoise filter. It aims to reduce
+image noise, producing smooth images and making still images really
+still. It should enhance compressibility.
+
+It accepts the following optional parameters:
+
+@table @option
+@item luma_spatial
+A non-negative floating point number which specifies spatial luma strength.
+It defaults to 4.0.
+
+@item chroma_spatial
+A non-negative floating point number which specifies spatial chroma strength.
+It defaults to 3.0*@var{luma_spatial}/4.0.
+
+@item luma_tmp
+A floating point number which specifies luma temporal strength. It defaults to
+6.0*@var{luma_spatial}/4.0.
+
+@item chroma_tmp
+A floating point number which specifies chroma temporal strength. It defaults to
+@var{luma_tmp}*@var{chroma_spatial}/@var{luma_spatial}.
+@end table
+
+@anchor{hwupload_cuda}
+@section hwupload_cuda
+
+Upload system memory frames to a CUDA device.
+
+It accepts the following optional parameters:
+
+@table @option
+@item device
+The number of the CUDA device to use
+@end table
+
+@section hqx
+
+Apply a high-quality magnification filter designed for pixel art. This filter
+was originally created by Maxim Stepin.
+
+It accepts the following option:
+
+@table @option
+@item n
+Set the scaling dimension: @code{2} for @code{hq2x}, @code{3} for
+@code{hq3x} and @code{4} for @code{hq4x}.
+Default is @code{3}.
+@end table
+
+@section hstack
+Stack input videos horizontally.
+
+All streams must be of same pixel format and of same height.
+
+Note that this filter is faster than using @ref{overlay} and @ref{pad} filter
+to create same output.
+
+The filter accept the following option:
+
+@table @option
+@item inputs
+Set number of input streams. Default is 2.
+
+@item shortest
+If set to 1, force the output to terminate when the shortest input
+terminates. Default value is 0.
+@end table
+
+@section hue
+
+Modify the hue and/or the saturation of the input.
+
+It accepts the following parameters:
+
+@table @option
+@item h
+Specify the hue angle as a number of degrees. It accepts an expression,
+and defaults to "0".
+
+@item s
+Specify the saturation in the [-10,10] range. It accepts an expression and
+defaults to "1".
+
+@item H
+Specify the hue angle as a number of radians. It accepts an
+expression, and defaults to "0".
+
+@item b
+Specify the brightness in the [-10,10] range. It accepts an expression and
+defaults to "0".
+@end table
+
+@option{h} and @option{H} are mutually exclusive, and can't be
+specified at the same time.
+
+The @option{b}, @option{h}, @option{H} and @option{s} option values are
+expressions containing the following constants:
+
+@table @option
+@item n
+frame count of the input frame starting from 0
+
+@item pts
+presentation timestamp of the input frame expressed in time base units
+
+@item r
+frame rate of the input video, NAN if the input frame rate is unknown
+
+@item t
+timestamp expressed in seconds, NAN if the input timestamp is unknown
+
+@item tb
+time base of the input video
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Set the hue to 90 degrees and the saturation to 1.0:
+@example
+hue=h=90:s=1
+@end example
+
+@item
+Same command but expressing the hue in radians:
+@example
+hue=H=PI/2:s=1
+@end example
+
+@item
+Rotate hue and make the saturation swing between 0
+and 2 over a period of 1 second:
+@example
+hue="H=2*PI*t: s=sin(2*PI*t)+1"
+@end example
+
+@item
+Apply a 3 seconds saturation fade-in effect starting at 0:
+@example
+hue="s=min(t/3\,1)"
+@end example
+
+The general fade-in expression can be written as:
+@example
+hue="s=min(0\, max((t-START)/DURATION\, 1))"
+@end example
+
+@item
+Apply a 3 seconds saturation fade-out effect starting at 5 seconds:
+@example
+hue="s=max(0\, min(1\, (8-t)/3))"
+@end example
+
+The general fade-out expression can be written as:
+@example
+hue="s=max(0\, min(1\, (START+DURATION-t)/DURATION))"
+@end example
+
+@end itemize
+
+@subsection Commands
+
+This filter supports the following commands:
+@table @option
+@item b
+@item s
+@item h
+@item H
+Modify the hue and/or the saturation and/or brightness of the input video.
+The command accepts the same syntax of the corresponding option.
+
+If the specified expression is not valid, it is kept at its current
+value.
+@end table
+
+@section idet
+
+Detect video interlacing type.
+
+This filter tries to detect if the input frames as interlaced, progressive,
+top or bottom field first. It will also try and detect fields that are
+repeated between adjacent frames (a sign of telecine).
+
+Single frame detection considers only immediately adjacent frames when classifying each frame.
+Multiple frame detection incorporates the classification history of previous frames.
+
+The filter will log these metadata values:
+
+@table @option
+@item single.current_frame
+Detected type of current frame using single-frame detection. One of:
+``tff'' (top field first), ``bff'' (bottom field first),
+``progressive'', or ``undetermined''
+
+@item single.tff
+Cumulative number of frames detected as top field first using single-frame detection.
+
+@item multiple.tff
+Cumulative number of frames detected as top field first using multiple-frame detection.
+
+@item single.bff
+Cumulative number of frames detected as bottom field first using single-frame detection.
+
+@item multiple.current_frame
+Detected type of current frame using multiple-frame detection. One of:
+``tff'' (top field first), ``bff'' (bottom field first),
+``progressive'', or ``undetermined''
+
+@item multiple.bff
+Cumulative number of frames detected as bottom field first using multiple-frame detection.
+
+@item single.progressive
+Cumulative number of frames detected as progressive using single-frame detection.
+
+@item multiple.progressive
+Cumulative number of frames detected as progressive using multiple-frame detection.
+
+@item single.undetermined
+Cumulative number of frames that could not be classified using single-frame detection.
+
+@item multiple.undetermined
+Cumulative number of frames that could not be classified using multiple-frame detection.
+
+@item repeated.current_frame
+Which field in the current frame is repeated from the last. One of ``neither'', ``top'', or ``bottom''.
+
+@item repeated.neither
+Cumulative number of frames with no repeated field.
+
+@item repeated.top
+Cumulative number of frames with the top field repeated from the previous frame's top field.
+
+@item repeated.bottom
+Cumulative number of frames with the bottom field repeated from the previous frame's bottom field.
+@end table
+
+The filter accepts the following options:
+
+@table @option
+@item intl_thres
+Set interlacing threshold.
+@item prog_thres
+Set progressive threshold.
+@item rep_thres
+Threshold for repeated field detection.
+@item half_life
+Number of frames after which a given frame's contribution to the
+statistics is halved (i.e., it contributes only 0.5 to it's
+classification). The default of 0 means that all frames seen are given
+full weight of 1.0 forever.
+@item analyze_interlaced_flag
+When this is not 0 then idet will use the specified number of frames to determine
+if the interlaced flag is accurate, it will not count undetermined frames.
+If the flag is found to be accurate it will be used without any further
+computations, if it is found to be inaccurate it will be cleared without any
+further computations. This allows inserting the idet filter as a low computational
+method to clean up the interlaced flag
+@end table
+
+@section il
+
+Deinterleave or interleave fields.
+
+This filter allows one to process interlaced images fields without
+deinterlacing them. Deinterleaving splits the input frame into 2
+fields (so called half pictures). Odd lines are moved to the top
+half of the output image, even lines to the bottom half.
+You can process (filter) them independently and then re-interleave them.
+
+The filter accepts the following options:
+
+@table @option
+@item luma_mode, l
+@item chroma_mode, c
+@item alpha_mode, a
+Available values for @var{luma_mode}, @var{chroma_mode} and
+@var{alpha_mode} are:
+
+@table @samp
+@item none
+Do nothing.
+
+@item deinterleave, d
+Deinterleave fields, placing one above the other.
+
+@item interleave, i
+Interleave fields. Reverse the effect of deinterleaving.
+@end table
+Default value is @code{none}.
+
+@item luma_swap, ls
+@item chroma_swap, cs
+@item alpha_swap, as
+Swap luma/chroma/alpha fields. Exchange even & odd lines. Default value is @code{0}.
+@end table
+
+@section inflate
+
+Apply inflate effect to the video.
+
+This filter replaces the pixel by the local(3x3) average by taking into account
+only values higher than the pixel.
+
+It accepts the following options:
+
+@table @option
+@item threshold0
+@item threshold1
+@item threshold2
+@item threshold3
+Limit the maximum change for each plane, default is 65535.
+If 0, plane will remain unchanged.
+@end table
+
+@section interlace
+
+Simple interlacing filter from progressive contents. This interleaves upper (or
+lower) lines from odd frames with lower (or upper) lines from even frames,
+halving the frame rate and preserving image height.
+
+@example
+ Original Original New Frame
+ Frame 'j' Frame 'j+1' (tff)
+ ========== =========== ==================
+ Line 0 --------------------> Frame 'j' Line 0
+ Line 1 Line 1 ----> Frame 'j+1' Line 1
+ Line 2 ---------------------> Frame 'j' Line 2
+ Line 3 Line 3 ----> Frame 'j+1' Line 3
+ ... ... ...
+New Frame + 1 will be generated by Frame 'j+2' and Frame 'j+3' and so on
+@end example
+
+It accepts the following optional parameters:
+
+@table @option
+@item scan
+This determines whether the interlaced frame is taken from the even
+(tff - default) or odd (bff) lines of the progressive frame.
+
+@item lowpass
+Enable (default) or disable the vertical lowpass filter to avoid twitter
+interlacing and reduce moire patterns.
+@end table
+
+@section kerndeint
+
+Deinterlace input video by applying Donald Graft's adaptive kernel
+deinterling. Work on interlaced parts of a video to produce
+progressive frames.
+
+The description of the accepted parameters follows.
+
+@table @option
+@item thresh
+Set the threshold which affects the filter's tolerance when
+determining if a pixel line must be processed. It must be an integer
+in the range [0,255] and defaults to 10. A value of 0 will result in
+applying the process on every pixels.
+
+@item map
+Paint pixels exceeding the threshold value to white if set to 1.
+Default is 0.
+
+@item order
+Set the fields order. Swap fields if set to 1, leave fields alone if
+0. Default is 0.
+
+@item sharp
+Enable additional sharpening if set to 1. Default is 0.
+
+@item twoway
+Enable twoway sharpening if set to 1. Default is 0.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Apply default values:
+@example
+kerndeint=thresh=10:map=0:order=0:sharp=0:twoway=0
+@end example
+
+@item
+Enable additional sharpening:
+@example
+kerndeint=sharp=1
+@end example
+
+@item
+Paint processed pixels in white:
+@example
+kerndeint=map=1
+@end example
+@end itemize
+
+@section lenscorrection
+
+Correct radial lens distortion
+
+This filter can be used to correct for radial distortion as can result from the use
+of wide angle lenses, and thereby re-rectify the image. To find the right parameters
+one can use tools available for example as part of opencv or simply trial-and-error.
+To use opencv use the calibration sample (under samples/cpp) from the opencv sources
+and extract the k1 and k2 coefficients from the resulting matrix.
+
+Note that effectively the same filter is available in the open-source tools Krita and
+Digikam from the KDE project.
+
+In contrast to the @ref{vignette} filter, which can also be used to compensate lens errors,
+this filter corrects the distortion of the image, whereas @ref{vignette} corrects the
+brightness distribution, so you may want to use both filters together in certain
+cases, though you will have to take care of ordering, i.e. whether vignetting should
+be applied before or after lens correction.
+
+@subsection Options
+
+The filter accepts the following options:
+
+@table @option
+@item cx
+Relative x-coordinate of the focal point of the image, and thereby the center of the
+distortion. This value has a range [0,1] and is expressed as fractions of the image
+width.
+@item cy
+Relative y-coordinate of the focal point of the image, and thereby the center of the
+distortion. This value has a range [0,1] and is expressed as fractions of the image
+height.
+@item k1
+Coefficient of the quadratic correction term. 0.5 means no correction.
+@item k2
+Coefficient of the double quadratic correction term. 0.5 means no correction.
+@end table
+
+The formula that generates the correction is:
+
+@var{r_src} = @var{r_tgt} * (1 + @var{k1} * (@var{r_tgt} / @var{r_0})^2 + @var{k2} * (@var{r_tgt} / @var{r_0})^4)
+
+where @var{r_0} is halve of the image diagonal and @var{r_src} and @var{r_tgt} are the
+distances from the focal point in the source and target images, respectively.
+
+@section loop, aloop
+
+Loop video frames or audio samples.
+
+Those filters accepts the following options:
+
+@table @option
+@item loop
+Set the number of loops.
+
+@item size
+Set maximal size in number of frames for @code{loop} filter or maximal number
+of samples in case of @code{aloop} filter.
+
+@item start
+Set first frame of loop for @code{loop} filter or first sample of loop in case
+of @code{aloop} filter.
+@end table
+
+@anchor{lut3d}
+@section lut3d
+
+Apply a 3D LUT to an input video.
+
+The filter accepts the following options:
+
+@table @option
+@item file
+Set the 3D LUT file name.
+
+Currently supported formats:
+@table @samp
+@item 3dl
+AfterEffects
+@item cube
+Iridas
+@item dat
+DaVinci
+@item m3d
+Pandora
+@end table
+@item interp
+Select interpolation mode.
+
+Available values are:
+
+@table @samp
+@item nearest
+Use values from the nearest defined point.
+@item trilinear
+Interpolate values using the 8 points defining a cube.
+@item tetrahedral
+Interpolate values using a tetrahedron.
+@end table
+@end table
+
+@section lut, lutrgb, lutyuv
+
+Compute a look-up table for binding each pixel component input value
+to an output value, and apply it to the input video.
+
+@var{lutyuv} applies a lookup table to a YUV input video, @var{lutrgb}
+to an RGB input video.
+
+These filters accept the following parameters:
+@table @option
+@item c0
+set first pixel component expression
+@item c1
+set second pixel component expression
+@item c2
+set third pixel component expression
+@item c3
+set fourth pixel component expression, corresponds to the alpha component
+
+@item r
+set red component expression
+@item g
+set green component expression
+@item b
+set blue component expression
+@item a
+alpha component expression
+
+@item y
+set Y/luminance component expression
+@item u
+set U/Cb component expression
+@item v
+set V/Cr component expression
+@end table
+
+Each of them specifies the expression to use for computing the lookup table for
+the corresponding pixel component values.
+
+The exact component associated to each of the @var{c*} options depends on the
+format in input.
+
+The @var{lut} filter requires either YUV or RGB pixel formats in input,
+@var{lutrgb} requires RGB pixel formats in input, and @var{lutyuv} requires YUV.
+
+The expressions can contain the following constants and functions:
+
+@table @option
+@item w
+@item h
+The input width and height.
+
+@item val
+The input value for the pixel component.
+
+@item clipval
+The input value, clipped to the @var{minval}-@var{maxval} range.
+
+@item maxval
+The maximum value for the pixel component.
+
+@item minval
+The minimum value for the&n