BIOMETRICS AUTHENTICATION DEVICE AND BIOMETRICS AUTHENTICATION METHOD

A biometrics authentication device is configured so as to include: a PLDI (Principal-Line Dependent Index) generating unit that extracts directional features that respectively correspond to directions different from each other from an image, and generates a PLDI (Principal-Line Dependent Index) indicating dependency of a principal line on the basis of the directional features; a PLDI (Principal-Line Dependent Index) matching processing unit that determines a second degree of similarity between the PLDI and a registered PLDI; and a determining unit that determines identity by using a first degree of similarity.