Look at the sample pic at http://coolhaus.de/misc/how2blur.jpg

The leftmost square shows the source image, the middle square shows the result of blurring (which I don't like), the rightmost shows the result I'd like to achieve, but I don't know how to.

I want to blur the blue parts of the figure.

I arrived at the middle figure by marking the blue square (minus the inner white circle) and using the gaussian blur filter. This results in some color from outside the mark (in this case, white) to bleed into the blurred area.

That is not what I want. I want the blurring to occur only based on the marked area, like shown in the rightmost square.

Can this be done somehow (in CS2)?

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