Guoqiang Li, Bian Yang, Christoph Busch Norwegian Biometrics Laboratory, Gjøvik University College, Norway Norwegian Biometrics Laboratory A Score‐level Fusion Fingerprint Indexing Approach based on Minutiae Vicinity and Minutia Cylinder‐Code 1 • Fingerprint indexing • State of art on feature extraction • Proposed Score‐level fusion approach • Experimental Results • Conclusion Norwegian Biometrics Laboratory Outline 2 Fingerprint indexing Enrolment Feature extraction Index table Database The basic structure of Fingerprint indexing A list of comparison scores sorted by descending order A short list of candidates Norwegian Biometrics Laboratory ¾ Fingerprint indexing is a technique to reduce the number of candidate identities to be considered by the verification algorithm. Feature extraction Retrieval 3 ¾ Global features: [Liu et al. 2012] fingerprint image Orientation field [Jiang et al. 2006] ¾ Local features: ¾ Other features: Norwegian Biometrics Laboratory State of the art on feature extraction [Li et al. 2006] 4 Delaunay triangulation Three features are based on the geometry of the triangle; Six features are extracted from the ridges associated with three minutiae. Norwegian Biometrics Laboratory State of the art on feature extraction [Ross and Mukherjee. 2007] 5 State of the art on feature extraction 3D local structure Computing a numerical value for each cube. Norwegian Biometrics Laboratory Minutia Cylinder‐Code (MCC) 2D local structure [Cappelli et al. 2011] 6 Proposed feature extraction Each triangle is represented by a 9‐D feature vector: ¾ 4 geometric features: Norwegian Biometrics Laboratory Delaunay triangulation 7 Proposed feature extraction ¾ ¾ 3 features based on the minutia direction info.; Norwegian Biometrics Laboratory ¾ 1 feature is the average value of ridge curvatures from three minutiae; 1 feature is based on the ridge density around the location of the minutia neighbors; [Tomasz and Wieclaw, 2011] 8 ¾ Design a new indexing method using this feature vector; ¾ A score-level fusion approach by by combing the Minutiae Vicinity (MV) indexing method with the minutiae cylinder-code (MCC) indexing method; Norwegian Biometrics Laboratory Proposed a score‐level fusion method Structure of proposed approach 9 Training set 9‐D feature vector from trianing set K‐means algorithm 0 0 1 0 1 . . . A set of feature vectors . . . Feature extraction 1 . . . Each feature vector 0 0 0 Norwegian Biometrics Laboratory Minutiae Vicinity based indexing method 10 Proposed a score‐level fusion method Reference samples Each subject will be represented by a K-dimension binary string. Norwegian Biometrics Laboratory MV-Index space will be represented by a matrix M whose size is R * K, where R is the number of subjects enrolled in the database, K is the number of clusters. A example of MV-Index space 11 Proposed a score‐level fusion method Feature extraction 3 56 . . . A set of feature vectors Each feature vector . . . 0 2 . . . 0 1 0 . . . Norwegian Biometrics Laboratory Retrieval in minutiae vicinity (MV) based index Space 1 12 Performance measures Pre‐selection error : error that occurs when the corresponding enrolment template is not in the preselected subset of candidates when a sample from the same biometric characteristic on the same user is given; Penetration rate : measure of the average number of pre‐selected templates as a fraction of the total number of templates; The number of candidates: 10 Enrolled 1,000 subjects Database Penetration rate: 10/1,000 =1% If 10 probes are outside of the candidates list, pre‐selection error: 10/100 = 10%; If 5 probes are outside of the candidates list, pre‐selection error: 5/100 = 5%; The number of candidates: 50 Norwegian Biometrics Laboratory From ISO/IEC 19795‐1 Penetration rate: 50/1,000 =5% 100 probe samples Each probe sample Low peneration rate, and low pre‐selection error 13 20 15 10 5 [Ross et al. 2007] 40.04 43.03 45.97 48.75 MV‐Index 12 17.38 26 48.5 MCC‐Index <1 2.94 7 16.5 MV‐MCC fusion <1 <1 1.19 8.9 Pre‐selection Error Rate(%) Penetration Rate(%) Performance evaluation of MV-MCC fusion, MCC-index, MV-Index and [Ross et al. 2007] on database FVC_2004_DB1. 20 15 10 5 [Ross et al. 2007] 40.79 43.61 46.45 49.34 MV‐Index 10 18.25 32.33 45.75 MCC‐Index 1.8 4.93 15 29.5 MV‐MCC fusion <1 <1 2.4 9.75 Pre‐selection Error Rate(%) Database preparation Penetration Rate(%) Norwegian Biometrics Laboratory Experimental results Performance evaluation of MV-MCC fusion, MCC-index, MV-Index and [Ross et al. 2007] on database FVC_2004_DB2. 14 Database preparation Performance evaluation of MV-MCC fusion, MCC-index, MV-Index on database FVC_2004_DB1_a. Norwegian Biometrics Laboratory Experimental results 15 Performance evaluation of MV-MCC fusion, MCC-index, MV-Index on database FVC_2004_DB2_a. Norwegian Biometrics Laboratory Experimental results 16 • Extracted a feature vector including 9 components based on the minutiae vicinity; • Developed a new indexing method using this feature vector; • Proposed a scole‐level fusion approach by combing this new method with minutia cylinder‐code (MCC) indexing method; • Future works: • • Improve the performance of indexing method based on the minutiae vicinity; Consider to set‐up the fusion on feature level; Norwegian Biometrics Laboratory Conclusion 17 • [VeriFinger] “Verifinger,” http://www.neurotechnology.com/verifinger.html, Accessed: 2013‐10‐30. • [Quinn and Grother. 2012 ] George W Quinn and Patrick Grother, “The one‐tomany multi‐modal fusion challenge,” in Biometrics (ICB), 2012 5th IAPR International Conference on. • [A reviewer. 2006 ] A Review of the FBI’s Handling of the Brandon Mayfield Case. http://www.justice.gov/oig/special/s0601/exec.pdf. • [Liu et al. 2012] Reference: Manhua Liu, Pew‐Thian Yap: Invariant representation of orientation fields for fingerprint indexing. Pattern Recognition 45(7): 2532‐2542 (2012). • [Li et al. 2006] Jun Li, Wei‐Yun Yau, and Han Wang, “Fingerprint indexing based on symmetrical measurement,” in Pattern Recognition, 2006. ICPR 2006. 18th International Conference on. IEEE, 2006, vol. 1, pp. 1038–1041. • [Ross and Mukherjee. 2007] Arun Ross and Rajiv Mukherjee, “Augmenting ridge curves with minutiae triplets for fingerprint indexing,” in Proceedings of SPIE Conference on Biometric Technology for Human Identification IV, 2007, vol. 6539, p. 65390C. • [Cappelli et al. 2011] Raffaele Cappelli, Matteo Ferrara, and Davide Maltoni, “Fingerprint indexing based on minutia cylinder‐code,” Pattern Analysis and Machine Intelligence, IEEE Transactionson, vol. 33, no. 5, pp. 1051–1057, 2011. • [Tomasz and Wieclaw, 2011] Orczyk, Tomasz, and Lukasz Wieclaw. "Fingerprint ridges frequency." Nature and Biologically Inspired Computing (NaBIC), 2011 Third World Congress on. IEEE, 2011. • [Jiang 2006] Jiang, Xudong, Manhua Liu, and Alex C. Kot. "Fingerprint retrieval for identification." Information Forensics and Security, IEEE Transactions on 1.4 (2006): 532‐ 542. Norwegian Biometrics Laboratory References 18 THANKS • The Norwegian Information Security Laboratory Norwegian Biometrics Laboratory • FIDELITY Project; 19