Minutia features generation apparatus, system, minutia features generation method, and program

A minutia features generation method, comprising:

• inputting an image formed as a curved stripe pattern by a ridge line(s);
• generating a skeleton image formed by extracting a skeleton(s) from the image;
• generating a ridge line direction data including information related to a ridge line direction at each point of the ridge line(s) making up the image;
• extracting a plurality of minutiae from the skeleton image;
• and
• calculating a relation minutia feature(s) representing relationship between a first minutia and a second minutia among the plurality of minutiae, wherein
• the calculating is performed by:
• calculating a minutia direction that features a direction of the first minutia;
• identifying a first nearest neighbor point candidate by performing a ridge line direction tracing in a first trace direction which is the same direction as the minutia direction using the ridge line direction data;
• identifying a second nearest neighbor point candidate by performing a ridge line direction tracing in a direction directed to a second trace direction which is an opposite direction of the minutia direction;
• and
• identifying a nearest neighbor point, which is closer one to the second minutia than another one among the first or second nearest neighbor point candidates;
• and
• calculating a trace direction relating to the nearest neighbor point as one of the relation minutia features.

A computer readable non-transient recording medium storing a program causing a computer to perform processing of:

• inputting an image formed as a curved stripe pattern by a ridge line(s);
• generating a skeleton image formed by extracting a skeleton(s) from the image;
• generating a ridge line direction data including information related to a ridge line direction at each point of the ridge line(s) making up the image;
• extracting a plurality of minutiae from the skeleton image;
• and
• calculating a relation minutia feature(s) representing relationship between a first minutia and a second minutia among the plurality of minutiae, wherein,
• the calculating is performed by:
• calculating a minutia direction that features a direction of the first minutia;
• identifying a first nearest neighbor point candidate by performing a ridge line direction tracing in a first trace direction which is the same direction as the minutia direction using the ridge line direction data;
• identifying a second nearest neighbor point candidate by performing a ridge line direction tracing in a direction directed to a second trace direction which is an opposite direction of the minutia direction;
• and
• identifying a nearest neighbor point, which is closer one to the second minutia than another one among the first or second nearest neighbor point candidates;
• and
• calculating a trace direction relating to the nearest neighbor point as one of the relation minutia features.