Information processing apparatus, recording medium for recording biometric authentication program, and biometric authentication method

A non-transitory computer-readable recording medium for recording a biometric authentication program which causes a computer to execute a process, the process comprising:

• extracting a plurality of feature points from a biometric image of a living body that is to be authenticated;
• generating a plurality of first groups each including a certain number of feature points among the plurality of feature points;
• obtaining a first feature value of each of the plurality of first groups;
• comparing, for each of the plurality of first groups, the first feature value with a second feature value of each of a plurality of second groups each including the certain number of feature points included in enrolled biometric information and stored in the memory;
• extracting one or more second groups, which are similar to each of the plurality of first groups, from among the plurality of second groups;
• specifying, as a first combination, a combination of each of the plurality of first groups and the one or more second groups;
• obtaining a first degree of similarity between a first feature point included in a first group of the first combination and a second feature point included in the one or more second groups of the first combination in accordance with a number of the one or more second groups;
• authenticating the living body based on the first degree of similarity;
• specifying, as a second combination, a combination of another first group and another one or more second groups which are similar to each other and are different from the first combination;
• and
• obtaining a second degree of similarity between a first feature point included in the another first group of the second combination and a fourth feature point included in a fourth group of the second combination in accordance with a number of the another one or more second groups, and wherein, when the number of the one or more second groups is greater than the number of the another one or more second groups, the first degree of similarity is smaller than the second degree of similarity.

A biometric authentication method comprising:

• extracting a plurality of feature points from a biometric image of a living body that is to be authenticated;
• generating a plurality of first groups each including a certain number of feature points among the plurality of feature points;
• obtaining a first feature value of each of the plurality of first groups;
• comparing, for each of the plurality of first groups, the first feature value with a second feature value of each of a plurality of second groups each including the certain number of feature points included in enrolled biometric information and stored in the memory;
• extracting one or more second groups, which are similar to each of the plurality of first groups, from among the plurality of second groups;
• specifying, as a first combination, a combination of each of the plurality of first groups and the one or more second groups;
• obtaining a first degree of similarity between a first feature point included in a first group of the first combination and a second feature point included in the one or more second groups of the first combination in accordance with a number of the one or more second groups;
• authenticating the living body based on the first degree of similarity;
• specifying, as a second combination, a combination of another first group and another one or more second groups which are similar to each other and are different from the first combination;
• and
• obtaining a second degree of similarity between a first feature point included in the another first group of the second combination and a fourth feature point included in a fourth group of the second combination in accordance with a number of the another one or more second groups, and wherein, when the number of the one or more second groups is greater than the number of the another one or more second groups, the first degree of similarity is smaller than the second degree of similarity.