1. An image display device comprising: a processing device that controls: displaying a still image or a moving image; capturing an image in a direction in which the still image or the moving image is displayed; and carrying out face detection processing, in which a face of a user which is included in the image captured is detected, at given intervals, and in which the face detection processing is carried out on a variable region of the image captured, wherein the face detection processing is performed (i) at a first frequency and on a first region of the image captured, when the face of the user is not detected in the image captured, and (ii) at a second frequency and on a second region of the image captured, when the face of the user is detected in the image captured, and wherein when the detected face undergoes no change in position in whole or in part for a given time in the course of the face detection processing, the processing device does not detect the face as the face of the user.