To provide an image display device enabling a user to easily confirm a focusing or the like in case of a photographing even by using a conventional small-sized liquid-crystal monitor.

A brightness signal is extracted from a video signal for a subject image obtained by an image sensing system, and the variation of the amplitude of the extracted brightness signal is operated arithmetically and or logically. A contour signal is extracted from the extracted brightness signal, and the amplitude of the extracted contour signal is operated arithmetically and or logically. The ratio of the variation of the brightness signal to the amplitude of the contour signal is operated arithmetically and or logically, and the contour signal is changed into any color in response to the result of the arithmetic and logic operation. The color-changed contour signal and the brightness signal are added, and the video signal adding the color-changed contour signal is displayed.