1. An image processing method, for extracting edges from digital photographic images and for obtaining edge data that represents the states of the edges, comprising the steps of: determining reduction intensities according to the sizes of the digital photographic images, such that the reduction intensities are increased for digital photographic images of greater sizes; administering reduction processes on the digital photographic images, employing the determined reduction intensities, to obtain reduced images; and extracting the edges, from which the edge data is obtained, from the reduced images; analyzing the edge data in order to detect states of blur in the digital photographic images; and correcting the detected states of blur in the digital photographic images.