Abstract: An outer surface of an object 23 is irradiated with visible light from a light source 21, and the reflected light is acquired by a TV camera 24. A two-dimensional image with gradation is Fourier transformed by an image analyzer 20. The brightness and darkness of the image are bipolarized using an emphasis coefficient in a predetermined wavelength range in the process of Fourier transform. The bright regions and dark regions forming closed regions are calculated separately as regions representing gloss irregularity or printing unevenness, thereby outputting a statistical parameter of the areas as a measured result.