@var{FILTERGRAPH} ::= [sws_flags=@var{flags};] @var{FILTERCHAIN} [;@var{FILTERGRAPH}]
@end example
+@anchor{filtergraph escaping}
@section Notes on filtergraph escaping
Filtergraph description composition entails several levels of
Another feature of this filter is the logarithmic mode.
This setting switches from linear distances between bits to logarithmic ones.
The result is a much more "natural" sounding crusher which doesn't gate low
-signals for example. The human ear has a logarithmic perception, too
+signals for example. The human ear has a logarithmic perception,
so this kind of crushing is much more pleasant.
Logarithmic crushing is also able to get anti-aliased.
The transition time, in seconds, for volume renormalization when an input
stream ends. The default value is 2 seconds.
+@item weights
+Specify weight of each input audio stream as sequence.
+Each weight is separated by space. By default all inputs have same weight.
@end table
@section anequalizer
@table @option
@item length
Short window length in seconds, used for peak and trough RMS measurement.
-Default is @code{0.05} (50 milliseconds). Allowed range is @code{[0.1 - 10]}.
+Default is @code{0.05} (50 milliseconds). Allowed range is @code{[0.01 - 10]}.
@item metadata
If no mapping is present, the filter will implicitly map input channels to
output channels, preserving indices.
+@subsection Examples
+
+@itemize
+@item
For example, assuming a 5.1+downmix input MOV file,
@example
ffmpeg -i in.mov -filter 'channelmap=map=DL-FL|DR-FR' out.wav
will create an output WAV file tagged as stereo from the downmix channels of
the input.
+@item
To fix a 5.1 WAV improperly encoded in AAC's native channel order
@example
ffmpeg -i in.wav -filter 'channelmap=1|2|0|5|3|4:5.1' out.wav
@end example
+@end itemize
@section channelsplit
@table @option
@item channel_layout
The channel layout of the input stream. The default is "stereo".
+@item channels
+A channel layout describing the channels to be extracted as separate output streams
+or "all" to extract each input channel as a separate stream. The default is "all".
+
+Choosing channels not present in channel layout in the input will result in an error.
@end table
+@subsection Examples
+
+@itemize
+@item
For example, assuming a stereo input MP3 file,
@example
ffmpeg -i in.mp3 -filter_complex channelsplit out.mkv
will create an output Matroska file with two audio streams, one containing only
the left channel and the other the right channel.
+@item
Split a 5.1 WAV file into per-channel files:
@example
ffmpeg -i in.wav -filter_complex
side_right.wav
@end example
+@item
+Extract only LFE from a 5.1 WAV file:
+@example
+ffmpeg -i in.wav -filter_complex 'channelsplit=channel_layout=5.1:channels=LFE[LFE]'
+-map '[LFE]' lfe.wav
+@end example
+@end itemize
+
@section chorus
Add a chorus effect to the audio.
used to prevent clipping.
@end table
+@section drmeter
+Measure audio dynamic range.
+
+DR values of 14 and higher is found in very dynamic material. DR of 8 to 13
+is found in transition material. And anything less that 8 have very poor dynamics
+and is very compressed.
+
+The filter accepts the following options:
+
+@table @option
+@item length
+Set window length in seconds used to split audio into segments of equal length.
+Default is 3 seconds.
+@end table
+
@section dynaudnorm
Dynamic Audio Normalizer.
@end example
@item
-Apply bass vinyl plugin from Calf:
+Apply vinyl plugin from Calf:
@example
lv2=p=http\\\\://calf.sourceforge.net/plugins/Vinyl:c=drone=0.2|aging=0.5
@end example
@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.
+width. Default is 0.5.
@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.
+height. Default is 0.5.
@item k1
-Coefficient of the quadratic correction term. 0.5 means no correction.
+Coefficient of the quadratic correction term. This value has a range [-1,1]. 0 means
+no correction. Default is 0.
@item k2
-Coefficient of the double quadratic correction term. 0.5 means no correction.
+Coefficient of the double quadratic correction term. This value has a range [-1,1].
+0 means no correction. Default is 0.
@end table
The formula that generates the correction is:
ffmpeg -i in.avi -vf "vflip" out.avi
@end example
+@section vfrdet
+
+Detect variable frame rate video.
+
+This filter tries to detect if the input is variable or constant frame rate.
+
+At end it will output number of frames detected as having variable delta pts,
+and ones with constant delta pts.
+If there was frames with variable delta, than it will also show min and max delta
+encountered.
+
@anchor{vignette}
@section vignette
@item aflat
Similar as above, but shows difference between blue and red chroma.
+@item xflat
+Similar as above, but use different colors.
+
@item chroma
Displays only chroma.
@item green
Display green graticule showing legal broadcast ranges.
+
+@item orange
+Display orange graticule showing legal broadcast ranges.
@end table
@item opacity, o
@end itemize
+@subsection Commands
+
+This filter supports the following commands:
+@table @option
+@item next
+Close the current segment and step to the next one
+@end table
+
@section drawgraph, adrawgraph
Draw a graph using input video or audio metadata.
Set channel height, allowed range is [1, 900]. Default is 20.
@item f
-Set fade, allowed range is [0.001, 1]. Default is 0.95.
+Set fade, allowed range is [0, 1]. Default is 0.95.
@item c
Set volume color expression.
If set, displays volume values. Default is enabled.
@item o
-Set orientation, can be @code{horizontal} or @code{vertical},
-default is @code{horizontal}.
+Set orientation, can be horizontal: @code{h} or vertical: @code{v},
+default is @code{h}.
@item s
-Set step size, allowed range s [0, 5]. Default is 0, which means
+Set step size, allowed range is [0, 5]. Default is 0, which means
step is disabled.
+
+@item p
+Set background opacity, allowed range is [0, 1]. Default is 0.
+
+@item m
+Set metering mode, can be peak: @code{p} or rms: @code{r},
+default is @code{p}.
@end table
@section showwaves
@end table
Default is linear.
+
+@item draw
+Set the draw mode. This is mostly useful to set for high @var{n}.
+
+Available values are:
+@table @samp
+@item scale
+Scale pixel values for each drawn sample.
+
+@item full
+Draw every sample directly.
+@end table
+
+Default value is @code{scale}.
@end table
@subsection Examples
@code{zmq} and @code{azmq} work as a pass-through filters. @code{zmq}
must be inserted between two video filters, @code{azmq} between two
-audio filters.
+audio filters. Both are capable to send messages to any filter type.
To enable these filters you need to install the libzmq library and
headers and configure FFmpeg with @code{--enable-libzmq}.
The @code{zmq} and @code{azmq} filters work as a libzmq server, which
receives messages sent through a network interface defined by the
-@option{bind_address} option.
+@option{bind_address} (or the abbreviation "@option{b}") option.
+Default value of this option is @file{tcp://localhost:5555}. You may
+want to alter this value to your needs, but do not forget to escape any
+':' signs (see @ref{filtergraph escaping}).
The received message must be in the form:
@example
@end example
@var{TARGET} specifies the target of the command, usually the name of
-the filter class or a specific filter instance name.
+the filter class or a specific filter instance name. The default
+filter instance name uses the pattern @samp{Parsed_<filter_name>_<index>},
+but you can override this by using the @samp{filter_name@@id} syntax
+(see @ref{Filtergraph syntax}).
@var{COMMAND} specifies the name of the command for the target filter.
Look at @file{tools/zmqsend} for an example of a zmq client which can
be used to send commands processed by these filters.
-Consider the following filtergraph generated by @command{ffplay}
+Consider the following filtergraph generated by @command{ffplay}.
+In this example the last overlay filter has an instance name. All other
+filters will have default instance names.
+
@example
ffplay -dumpgraph 1 -f lavfi "
color=s=100x100:c=red [l];
color=s=100x100:c=blue [r];
nullsrc=s=200x100, zmq [bg];
-[bg][l] overlay [bg+l];
-[bg+l][r] overlay=x=100 "
+[bg][l] overlay [bg+l];
+[bg+l][r] overlay@@my=x=100 "
@end example
To change the color of the left side of the video, the following
echo Parsed_color_1 c pink | tools/zmqsend
@end example
+To change the position of the right side:
+@example
+echo overlay@@my x 150 | tools/zmqsend
+@end example
+
+
@c man end MULTIMEDIA FILTERS
@chapter Multimedia Sources
projects / ffmpeg / blobdiff