Electronic visual prostheses, or "bionic eyes," are likely to provide some coarse visual sensations to blind patients who have these systems implanted. The quality of artificially induced vision is anticipated to be very poor initially. Research described explores image processing techniques that improve perception for users of visual prostheses. We describe visual perception experiments undertaken with 192 normally sighted viewers to simulate artificially induced vision expected from emerging electronic visual prosthesis designs. Several variations of region-of-interest (ROI) processing were applied to images that were presented to subjects as low-resolution 25×25 binary images. Several additional processing methods were compared to determine their suitability for use in automatically controlling a zoom-type function for visual prostheses. The experiments show that ROI processing improves scene understanding for low-quality images when used in a zoom application.