1. In a computing environment, an image display system for permitting a portion of an image to be enlarged, said system comprising: image display means for displaying on a screen an image based on image data; region indicator means for identifying a region of the image to be enlarged; brightness adjusting means for adjusting brightness values of a portion of the image which corresponds to the region to be enlarged such that a contrast of the identified region when displayed within an enlarged display area on the screen is higher than a contrast of an original image within the enlarged display region; and data modification means for modifying a portion of the image data which corresponds to the enlarged display area within the image data so that the identified region of the image, after enlargement within the enlarged display region is enlarged and displayed in the enlarged display region on the screen.