Biometric recognition apparatus and biometric recognition method

A biometric recognition method comprising:

• generating, by a processor and from a plurality of first biometric images and a plurality of second biometric images, a plurality of pairs that are each a combination of a respective one of the first biometric images and a respective one of the second biometric images, the plurality of pairs including a genuine pair and an imposter pair;
• using, by the processor, a plurality of different temporary parameters to extract feature templates from the first biometric image and the second biometric image of each pair;
• calculating, by the processor, a similarity degree of the feature templates extracted from the first biometric image and the second biometric image of each pair;
• calculating, by the processor, a first score representing the similarity degree of the feature templates extracted from the first biometric image of the genuine pair;
• in response to the first score being greater than or equal to a predetermined value, replacing, by the processor, the genuine pair with a new genuine pair and recalculate the first score;
• calculating, by the processor, a second score representing the similarity degree of the feature templates extracted from the first biometric image and the second biometric image of the imposter pair;
• calculating, by the processor, a score separation degree on a temporary parameter basis based on the first score and the score second;
• and
• determining, by the processor, the temporary parameter based on a level of the score separation degree.

A computer readable non-transitory storage medium storing a program that is executable by a computer to cause the computer to perform:

• generating, from a plurality of first biometric images and a plurality of second biometric images, a plurality of pairs that are each a combination of a respective one of the first biometric images and a respective one of the second biometric images, the plurality of pairs including a genuine pair and an imposter pair;
• using a plurality of different temporary parameters to extract feature templates from the first biometric image and the second biometric image of each pair;
• calculating a similarity degree of the feature templates extracted from the first biometric image and the second biometric image of each pair;
• calculating a first score representing the similarity degree of the feature templates extracted from the first biometric image of the genuine pair;
• in response to the first score being greater than or equal to a predetermined value, replacing the genuine pair with a new genuine pair and recalculate the first score;
• calculating a second score representing the similarity degree of the feature templates extracted from the first biometric image and the second biometric image of the imposter pair;
• calculating a score separation degree on a temporary parameter basis based on the first score and the score second;
• and
• determining the temporary parameter based on a level of the score separation degree.