US Patent 7454134 Image signal processing unit and digital camera

An image signal processing unit which processes image signals corresponding to an image divided into a plurality of image-areas is provided. The image signal processing unit comprises a first detector, a second detector, and a blurring processor. The first detector detects a sharpness. The sharpness corresponds to how much of the image-area is in focus based on the image signals. The second detector detects an out-of-focus area from the image-areas when the sharpness of an out-of-focus area is out of a predetermined permissible range. The blurring processor carries out a blurring process for the out-of-focus area signal corresponding to the out-of-focus area.