Embird has one in Studio + sfumato. www.embird.net/
Is that what you mean. don't think it does it automaticlally though you have to digitize it your self, I have it but not done a lot with it as yet.
I am sure there are other programas also...

Good luck, the Embird Sfumato program is the only one I know of, and I don't have the slightest idea how it works. Who is the aussie lady who is a digitizer (not you, Meganne, hee hee hee) who has a website & did a lot of photos for people here, for a rather reasonable price? Just can't for the life of me remember her name or screen name, but she does good work, maybe she'd know. Hugs, Marji