1. A system executed by a computer to determine a recognition target pattern present in a target image, the system comprising: a processing unit operatively coupled to memory; dictionary image data including a recognition target pattern, a plurality of feature points of the recognition target pattern including a size (Rm) and direction (θm) of a feature vector, and an offset (Ox, Oy) from coordinates at a center of an image to coordinates of a feature point; sizes (Rt) and directions (θt) of feature vectors for coordinates (Tx, Ty) of a plurality of feature points in the target image; the processing unit to calculate coordinates (Fx, Fy) of a virtual center point in the target image derived from Tx, Ty, Ox, Oy, Rm, Rt, θm, and θt; the processing unit to count additional virtual center points within a radius (r) of the coordinates (Fx, Fy) of the virtual center point; and data storage to store the coordinates (Fx, Fy) of the virtual center point and the number of counted virtual center points as candidates, wherein each feature point in the plurality of feature points in the target image is a matching feature point of at least one feature point in the target image and at least one feature point in the recognition target pattern.