I am really impressed by the new set of image processing operations in Mathematica 9. I am, however, having trouble defining my own operations, and one of the things I do very frequently in another system, is neighborhood operations. I would like to do these things in Mathematica,and would like so help:
How do I define a function that takes an Image, and performs operations, say, on a 3x3 nbdh for all pixels. I would like to use the functional programming paradigm. Filter is one such operation. I would love to see how Mathematica does it internally, but I am not able to find it.