US Patent 6972771 Image display device, image display method, and image display program

A technique is provided for improving visual recognition of letters, graphics, etc., in a portion of a displayed image that has been enlarged. An image display system includes an image display component for displaying on a screen an image based on image data, a region indicator component for permitting a region to be enlarged from the image to be selected and identified, a data modification component for modifying the portion of the image data corresponding to an enlarged display region so that the selected image is enlarged and displayed within the enlarged display region on the screen, and a brightness adjusting component for adjusting values instructing brightness of the corresponding image data part such that a contrast of the image within the enlarged display is higher than a contrast of the original image within the enlarged display region.