Image recognition followed by a timed response

[Gertjan Roelandt]

Hello, i'm new to this board.

I was wondering if it is at all possible to write a script, that can recognize a certain image (not a a font or specified file) that shows up on your screen randomly.
Then once it recognized that image it should forward a simple command (like "pg_up" or "pg_down") if the image is in certain position (xy coordinates) on your screen.

I know things like these are possible in windows using scripting within macro building programs that support image recognition, but i dont know how to start making this in an OS X environment.

All help is welcome