Patent ID: 7190401

Claim:
An image processing apparatus comprising: a signal generator for generating an image signal of a luminance reference image that provides a standard for determining a luminance; a mixer that uses an input image signal and the image signal of the luminance reference image to generate an image signal for displaying a combination of a display image based on the input image signal and the luminance reference image; a discriminator for carrying out signal discrimination of the input image signal having means for determining an aspect ratio of the input image signal, and means for detecting whether a region with no image occurs on a display screen based on the determined aspect ratio; wherein the signal generator produces the image signal of the luminance reference image based on a discrimination result supplied by the discriminator, and wherein if the discriminator detects that a region with no image occurs on the display screen, the signal generator produces the image signal of the luminance reference image so that the luminance reference image is displayed in the region with no image.