Image manipulation

I would like to find out how i would go about programatically finding the areas in the green boxes on something LIKE http://jabab.com/image.PNG The green boxes would not be there, and i would be blitting these areas after.

Is this an attempt to get past those image verification scripts to stop computers from signing up? :whoops:

Anyways.. There are many ways of OCR (optical text recognition), while none of them are gonna be easy.. Search this forum and google.