1. A fingerprint information processing apparatus comprising: first detection means for detecting from a fingerprint image first feature points which are either ridge bifurcations or ridge endings of a fingerprint; second detection means for detecting a center point which is a center of a registered image; determination means for determining distances between the center point and each of the plurality of first feature points; sorting means for sorting the first feature points in order of the distance determined by the determination means; first generation means for generating a plurality of triangles, each triangle connecting three points selected from the plurality of first feature points, wherein in each triangle, the three points include a first point which is selected from the sorted first feature points sorted by the sorting means, in order of increasing distance from the center point, and a second point which is closest to the first point in the triangle, and a third point which is second closest to the first point in the triangle; first calculation means for calculating an area and a length of each side of the triangle generated by the first generation means; and storage means for storing the area and the length of each side of the triangle calculated by the first calculation means.