Based on a difference image of three temporally consecutive frame images, a moving object region where a moving object is displayed and a background region are extracted from a central frame image. A processing of becoming a clear image such as contrast enhancement is performed on an image of the moving object region. On the other hand, a blurring processing such as an averaging processing is performed on an image of the background region. The image of the background region is blurred in this blurring processing so that the degree of blurring increases as the ratio of the moving object region in the frame image is high.