Merge commit 'b8f3ab8e6a7ce3627764da53b809628c828d4047'

[ffmpeg] / doc / filters.texi

diff --git a/doc/filters.texi b/doc/filters.texi
index 6f584d80d613200a6c9f0412c62f14f07a6c5fcc..271fe108afece30c3d6e886e5d7cc22da79e5476 100644 (file)
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -833,49 +833,64 @@ not meant to be used directly.
 
 Adjust the input audio volume.
 
-The filter accepts exactly one parameter @var{vol}, which expresses
-how the audio volume will be increased or decreased.
+The filter accepts the following named parameters. If the key of the
+first options is omitted, the arguments are interpreted according to
+the following syntax:
+@example
+volume=@var{volume}:@var{precision}
+@end example
+
+@table @option
+
+@item volume
+Expresses how the audio volume will be increased or decreased.
 
 Output values are clipped to the maximum value.
 
-If @var{vol} is expressed as a decimal number, the output audio
-volume is given by the relation:
+The output audio volume is given by the relation:
 @example
-@var{output_volume} = @var{vol} * @var{input_volume}
+@var{output_volume} = @var{volume} * @var{input_volume}
 @end example
 
-If @var{vol} is expressed as a decimal number followed by the string
-"dB", the value represents the requested change in decibels of the
-input audio power, and the output audio volume is given by the
-relation:
-@example
-@var{output_volume} = 10^(@var{vol}/20) * @var{input_volume}
-@end example
+Default value for @var{volume} is 1.0.
 
-Otherwise @var{vol} is considered an expression and its evaluated
-value is used for computing the output audio volume according to the
-first relation.
+@item precision
+Set the mathematical precision.
 
-Default value for @var{vol} is 1.0.
+This determines which input sample formats will be allowed, which affects the
+precision of the volume scaling.
+
+@table @option
+@item fixed
+8-bit fixed-point; limits input sample format to U8, S16, and S32.
+@item float
+32-bit floating-point; limits input sample format to FLT. (default)
+@item double
+64-bit floating-point; limits input sample format to DBL.
+@end table
+@end table
 
 @subsection Examples
 
 @itemize
 @item
-Half the input audio volume:
+Halve the input audio volume:
 @example
-volume=0.5
+volume=volume=0.5
+volume=volume=1/2
+volume=volume=-6.0206dB
 @end example
 
-The above example is equivalent to:
+In all the above example the named key for @option{volume} can be
+omitted, for example like in:
 @example
-volume=1/2
+volume=0.5
 @end example
 
 @item
-Decrease input audio power by 12 decibels:
+Increase input audio power by 6 decibels using fixed-point precision:
 @example
-volume=-12dB
+volume=volume=6dB:precision=fixed
 @end example
 @end itemize
 
@@ -919,59 +934,6 @@ There are 6 samples at -4 dB, 62 at -5 dB, 286 at -6 dB, etc.
 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.
 
-@section volume_justin
-
-Adjust the input audio volume.
-
-The filter accepts the following named parameters:
-@table @option
-
-@item volume
-Expresses how the audio volume will be increased or decreased.
-
-Output values are clipped to the maximum value.
-
-The output audio volume is given by the relation:
-@example
-@var{output_volume} = @var{volume} * @var{input_volume}
-@end example
-
-Default value for @var{volume} is 1.0.
-
-@item precision
-Mathematical precision.
-
-This determines which input sample formats will be allowed, which affects the
-precision of the volume scaling.
-
-@table @option
-@item fixed
-8-bit fixed-point; limits input sample format to U8, S16, and S32.
-@item float
-32-bit floating-point; limits input sample format to FLT. (default)
-@item double
-64-bit floating-point; limits input sample format to DBL.
-@end table
-@end table
-
-@subsection Examples
-
-@itemize
-@item
-Halve the input audio volume:
-@example
-volume_justin=volume=0.5
-volume_justin=volume=1/2
-volume_justin=volume=-6.0206dB
-@end example
-
-@item
-Increase input audio power by 6 decibels using fixed-point precision:
-@example
-volume_justin=volume=6dB:precision=fixed
-@end example
-@end itemize
-
 @c man end AUDIO FILTERS
 
 @chapter Audio Sources
@@ -3670,7 +3632,10 @@ output frames. It does not change the input frame, but only sets the
 corresponding property, which affects how the frame is treated by
 following filters (e.g. @code{fieldorder} or @code{yadif}).
 
-It accepts a string parameter, which can assume the following values:
+This filter accepts a single option @option{mode}, which can be
+specified either by setting @code{mode=VALUE} either setting the
+value alone. Available values are:
+
 @table @samp
 @item auto
 Keep the same field property.