[Gimp-user] Applying large blur only to selection

[Leonard Evens]

I want to blur the sky so that only pixels in the selection are used in
computing the new values.  Also, I need to use a large blur radius.
I've done this in the past by starting off with a small blur raidus and
progressively reducing the selection, increasing the (gaussian) blur
radius as I did so.  What is the simplest way to do  this?   If I just
apply a gaussin blur with a large radius  to my selection is uses values
outside the selection in calculationg the new values near the boundary
of the selection.
-- 
Leonard Evens <len at math.northwestern.edu>
Mathematics Department, Northwestern University