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Automatic biometric identification based on fingerprints is still one of the most reliable identification
methods in criminal and forensic applications. Fingerprint images are directionally oriented patterns formed
by ridges and valleys that can be captured from a finger with a multitude of sensors, particularly, capacitive,
optical, thermal sweeping and ultrasonic. Fingerprints are unique to each individual and have been widely used
for biometric identification. A critical step in fingerprint analysis without human intervention is to automatically
and reliably extract singular points from the input fingerprint images. The singular points - cores and deltas - are
the most important topological features of a fingerprint. The singular point area is defined as a region where the ridge
curvature is higher than normal and where the direction of the ridge changes rapidly. These singular points not only represent
the characteristics of local ridge patterns but also determine the topological structure (i.e., fingerprint type).
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