1. A visual prosthesis comprising: a video receiver for receiving a video image and converting said video image to a video signal; a video processing unit, coupled to said video receiver and processing said video signal; within a housing suitable to place external to a human body; a manually operable user interface on said housing, accepting user input and controlling said video processing unit and, thereby, electrode signal parameters; and a plurality of electrodes driven in accordance with said video signal and said electrode signal parameters, stimulating visual neurons to create a perception of said video image.