Biometric System Laboratory

Fingerprint Classification

The identification of a person requires the comparison of his/her fingerprint with all the fingerprints in a database, which in large scale applications may be very large (several million fingerprints). A common strategy to reduce the number of comparisons during fingerprint retrieval and, consequently, to improve the response time of the identification process, is to divide the fingerprints into some predefined classes.
Fingerprint classification means assigning each fingerprint to a class in a consistent and reliable way, such that an unknown fingerprint to be searched, needs to be compared only with the subset of fingerprints in the database belonging to the same class. While fingerprint matching is usually performed according to fingerprint micro-features, such as ridge terminations and bifurcations (minutiae), fingerprint classification is usually based on macro-features, such as global ridge structure.
All the classification schemes currently used by police agencies are variants of the so-called Henry�s classification scheme. Five classes (Arch, Tented arch, Left loop, Right loop and Whorl) are commonly used by today�s fingerprint classification techniques. In reality, fingerprints are not uniformly distributed among these five classes: the proportions have been estimated as 3.7%, 2.9%, 33.8%, 31.7% and 27.9% for Arch, Tented arch, Left loop, Right loop and Whorl, respectively.

Bibliography

(Click here if you are interested in any of the publications below)

	D. Maltoni, D. Maio, A.K. Jain and J. Feng, Handbook of Fingerprint Recognition (Third Edition), Springer Nature, 2022.
	D. Maltoni, D. Maio, A.K. Jain and S. Prabhakar, Handbook of Fingerprint Recognition (Second Edition), Springer (London), 2009.
	R. Cappelli and D. Maio, "The State of the Art in Fingerprint Classification", in N. Ratha and R. Bolle, Automatic Fingerprint Recognition Systems, Springer, 2004. Abstract
	R. Cappelli and M. Ferrara, "A Fingerprint Retrieval System Based on Level-1 and Level-2 Features", Expert Systems With Applications, vol.39, no.12, pp.10465-10478, September 2012. Abstract
	R. Cappelli, "Fast and Accurate Fingerprint Indexing based on Ridge Orientation and Frequency", IEEE Transactions on Systems, Man and Cybernetics - Part B, vol.41, no.6, pp.1511-1521, December 2011. Abstract
	R. Cappelli, M. Ferrara and D. Maio, "Candidate List Reduction based on the Analysis of Fingerprint Indexing Scores", IEEE Transactions on Information Forensics and Security, vol.6, no.3, pp.1160-1164, September 2011. Abstract
	R. Cappelli, M. Ferrara and D. Maltoni, "Fingerprint Indexing based on Minutia Cylinder-Code", IEEE Transactions on Pattern Analysis Machine Intelligence, vol.33, no.5, pp.1051-1057, May 2011. Abstract
	R. Cappelli and D. Maltoni, "On the Spatial Distribution of Fingerprint Singularities", IEEE Transactions on Pattern Analysis Machine Intelligence, vol.31, no.4, pp.742-748, April 2009. Abstract
	A. Lumini and L. Nanni, "FuzzyBagging: a novel ensemble of classifiers", Pattern Recognition, vol.39, no.3, pp.488-490, March 2006. Abstract
	R. Cappelli, D. Maio and D. Maltoni, "A Multi-Classifier Approach to Fingerprint Classification", Pattern Analysis and Applications Special Issue on Fusion of Multiple Classifiers, vol.5, no.2, pp.136-144, May 2002. Abstract
	A. Lumini, D. Maio and D. Maltoni, "Inexact Graph Matching for Fingerprint Classification", Machine GRAPHICS & VISION Special Issue on Graph Trasformations in Pattern Generation and CAD, vol.8, no.2, pp.231-248, September 1999. Abstract
	R. Cappelli, A. Lumini, D. Maio and D. Maltoni, "Fingerprint Classification by Directional Image Partitioning", IEEE Transactions on Pattern Analysis Machine Intelligence, vol.21, no.5, pp.402-421, May 1999. Abstract
	A. Lumini, D. Maio and D. Maltoni, "Continuous vs Exclusive Classification for Fingerprint Retrieval", Pattern Recognition Letters, vol.18, no.10, pp.1027-1034, October 1997. Abstract
	R. Cappelli, D. Maio, D. Maltoni and L. Nanni, "A two-stage fingerprint classification system", in proceedings ACM SIGMM Multimedia Biometrics Methods and Applications Workshop (WBMA03), Berkley, pp.95-99, November 2003. Abstract
	R. Cappelli, D. Maio and D. Maltoni, "Indexing Fingerprint Databases for Efficient 1:N Matching", in proceedings Sixth International Conference on Control, Automation, Robotics and Vision (ICARCV2000), Singapore, December 2000. Invited Paper. Abstract
	R. Cappelli, D. Maio and D. Maltoni, "Combining Fingerprint Classifiers", in proceedings First International Workshop on Multiple Classifier Systems (MCS2000), Cagliari, pp.351-361, June 2000. Abstract
	R. Cappelli, D. Maio and D. Maltoni, "Fingerprint Classification based on Multi-space KL", in proceedings Workshop on Automatic Identification Advances Technologies (AutoID'99), Summit (NJ), pp.117-120, October 1999. Abstract
	D. Maio and D. Maltoni, "A Structural Approach to Fingerprint Classification", in proceedings 13th International Conference on Pattern Recognition (ICPR), Vienna, pp.578-585, August 1996. Abstract
	A. Lumini, D. Maio and D. Maltoni, "Strategie per il retrieval di impronte digitali", in proceedings Sistemi Evoluti per Basi di Dati (SEBD97), Verona (Italy), pp.47-66, June 1997. Abstract