An image display device is provided with an image input unit configured to receive an image; an image quality setting unit configured to apply a plurality of image quality settings different from one another to the image received by the image input unit for obtaining a plurality of images whose image quality is different; an image composition unit configured to generate a composite image including the plural images whose image quality is different obtained in the image quality setting unit arranged as a plurality of image quality comparison images; and an image display unit configured to display the composite image generated in the image composition unit thereon.