OOF2: The Manual
OOF.Image.Modify.ReduceNoise — Reduce noise while preserving edges.
Smooth the contours of an image while still preserving edge
information. The algorithm works by replacing each pixel with its
neighbor closest in value. The neighbors of a pixel are defined
as those pixels within the given
specified in units of the pixel size. A suitable radius will be
chosen automatically if
radius is zero.
This routine comes from the ImageMagick library.