Fingerprint alignment using special ridges

Fingerprint is one of the biometrics used to identify a person. Alignment is an important step in fingerprint recognition, affecting greatly the speed and accuracy of matching. Eight types of Special ridges are introduced to align two fingerprints. The ridge with maximum of sampled curvature is used as reference ridges for initial alignment. And corresponding special ridges paired by topology get aligned by their features. The alignment parameters of translation and rotation finally come from all aligned special ridge pairs. Experiments show that alignment using special ridges is fast and robust.