| 摘要 |
PROBLEM TO BE SOLVED: To automatically extract the location and direction of the first joint line contained in a fingerprint image to be collated and to enable the stable positioning to improve the precision of a fingerprint collation by providing each specified vertical area separation part, a projection calculation part, a valley candidate calculation part and a valley information integration part. SOLUTION: A vertical area separation part 11 divides an input image into plural small areas (zones) by the straight line group parallel to a Y direction. A projection calculation part 12 performs the density projection processing in an X direction in each zone and determines a projection histogram. A valley candidate calculation part 13 determines the minimum point called as a valley from the obtained projection histogram. A valley degree of conviction calculation part 14 calculates the degree of conviction for each valley in each zone. A zone degree of conviction calculation part 15 calculates the degree of conviction for each zone. A valley information integration part 16 inputs the location of the valley obtained from the valley candidate calculation parts 13 in plural zones, the valley degree of conviction obtained from the valley degree of conviction calculation part 14 and the zone degree of conviction obtained from the zone degree of conviction calculation part 15 and determines the joint line location of the fingerprint image and the degree of conviction. |
