avfilter/smartblur: Added alpha layer support

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

1 files changed, 19 insertions, 1 deletions

diff --git a/doc/filters.texi b/doc/filters.texi
index 8230661261..f5bf475d13 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -22653,9 +22653,27 @@ whether a pixel should be blurred or not. The option value must be an
 integer in the range [-30,30]. A value of 0 will filter all the image,
 a value included in [0,30] will filter flat areas and a value included
 in [-30,0] will filter edges. Default value is @option{luma_threshold}.
+
+@item alpha_radius, ar
+Set the alpha radius. The option value must be a float number in
+the range [0.1,5.0] that specifies the variance of the gaussian filter
+used to blur the image (slower if larger). Default value is @option{luma_radius}.
+
+@item alpha_strength, as
+Set the alpha strength. The option value must be a float number
+in the range [-1.0,1.0] that configures the blurring. A value included
+in [0.0,1.0] will blur the image whereas a value included in
+[-1.0,0.0] will sharpen the image. Default value is @option{luma_strength}.
+
+@item alpha_threshold, at
+Set the alpha threshold used as a coefficient to determine
+whether a pixel should be blurred or not. The option value must be an
+integer in the range [-30,30]. A value of 0 will filter all the image,
+a value included in [0,30] will filter flat areas and a value included
+in [-30,0] will filter edges. Default value is @option{luma_threshold}.
 @end table
 
-If a chroma option is not explicitly set, the corresponding luma value
+If a chroma or alpha option is not explicitly set, the corresponding luma value
 is set.
 
 @section sobel