@item
Show text for 1 second every 3 seconds:
@example
-drawtext="fontfile=FreeSerif.ttf:fontcolor=white:x=100:y=x/dar:draw=lt(mod(t\\,3)\\,1):text='blink'"
+drawtext="fontfile=FreeSerif.ttf:fontcolor=white:x=100:y=x/dar:draw=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'
+drawtext='fontfile=Linux Libertine O-40\:style=Semibold:text=FFmpeg'
@end example
@end itemize
@item fps
Desired output framerate.
+@item round
+Rounding method. The default is @code{near}.
+
@end table
@section framestep
# add a transparent color layer on top of the main video,
# WxH specifies the size of the main input to the overlay filter
-color=red@.3:WxH [over]; [in][over] overlay [out]
+color=red@@.3:WxH [over]; [in][over] overlay [out]
# play an original video and a filtered version (here with the deshake filter)
# side by side
filter may be changed by later filters in the filterchain, e.g. if
another "setsar" or a "setdar" filter is applied.
-The @code{setdar} and @code{setsar} filters accept a parameter string
-which represents the wanted aspect ratio. The parameter can
-be a floating point number string, an expression, 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. If the parameter is not
-specified, it is assumed the value "0:1".
+The @code{setdar} and @code{setsar} filters accept a string in the
+form @var{num}:@var{den} expressing an aspect ratio, or the following
+named options, expressed as a sequence of @var{key}=@var{value} pairs,
+separated by ":".
+
+@table @option
+@item max
+Set the maximum integer value to use for expressing numerator and
+denominator when reducing the expressed aspect ratio to a rational.
+Default value is @code{100}.
+
+@item r, ratio:
+Set the aspect ratio used by the filter.
+
+The parameter can be a floating point number string, an expression, 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. If
+the parameter is not specified, it is assumed the value "0".
+In case the form "@var{num}:@var{den}" the @code{:} character should
+be escaped.
+@end table
+
+If the keys are omitted in the named options list, the specifed values
+are assumed to be @var{ratio} and @var{max} in that order.
For example to change the display aspect ratio to 16:9, specify:
@example
-setdar=16:9
+setdar='16:9'
@end example
The example above is equivalent to:
To change the sample aspect ratio to 10:11, specify:
@example
-setsar=10:11
+setsar='10:11'
+@end example
+
+To set a display aspect ratio of 16:9, and specify a maximum integer value of
+1000 in the aspect ratio reduction, use the command:
+@example
+setdar=ratio='16:9':max=1000
@end example
@section setfield