An image processing system that can reduce the amount of operations for compression processing includes a characteristic region detecting section that detects a characteristic region from an image and a compressing section that compresses the image by compressing each prescribed partial region. The compressing section compresses an image of a partial region included in a characteristic region by using pixel values of pixels, the number of which is larger than the number of pixels used for compressing an image of a partial region included in a region other than the characteristic region.