1. An image processing device for producing a restored image from an input degraded image, the restored image having smaller blur than the degraded image, the device comprising: an initial image setting section that sets a provisional restored image; an image block selection section that selects a plurality of image block pairs from the degraded image and the provisional restored image, each of the image block pairs being formed by two image blocks at identical coordinates in the degraded image and the provisional restored image; a PSF estimation section that obtains a plurality of point spread functions respectively corresponding to the plurality of image block pairs; a PSF selection section that selects a candidate point spread function which defines blur of the degraded image from among the plurality of point spread functions obtained in PSF estimation section; and an image restoration section that produces a restored image from the degraded image using the candidate point spread function.