1. A method of extracting facial features from an image containing a face, the method comprising: (a) filtering the image using a filter set for face recognition at each of predetermined locations in the image, the filtering including filtering one or more pairs of first values filtered at horizontally symmetrical locations from among the predetermined locations; (b) merging each pair of the first values filtered at the horizontally symmetrical locations from among the predetermined locations, wherein the horizontally symmetrical locations are horizontally symmetrical to each other with respect to a longitudinal axis disposed along a center of the face, into second values representing the each pair of the first values at the horizontally symmetrical locations; and (c) synthesizing third values filtered at locations, which are not horizontally symmetrical locations, from among the predetermined locations, with the second values, when the predetermined locations include locations other than the horizontally symmetrical locations.