Automatic Identification and Detection of Altered Fingerprints

Fingerprint recognition is one of the most commonly used biometric technology. Among various modalities of biometrics, fingerprints are known to have the longest history of actual use in law enforcement applications with proven performances. The widespread deployment of Automated Fingerprint Identification Systems (AFIS) in law enforcement and border control applications has heightened the need for ensuring that these systems are not compromised. While several issues related to fingerprint system security have been investigated, including the use of fake fingerprints for masquerading identity, the problem of fingerprint alteration or obfuscation has received very little attention. Fingerprint obfuscation refers to the deliberate alteration of the fingerprint pattern by an individual for the purpose of masking his identity. Fingerprint alteration refers to the deliberate alteration of the fingerprint pattern by a person for masking his/her identity. This paper presents a new method for identifying and detecting altered fingerprints based on fingerprint orientation field reliability. The main contributions of this paper are: 1) compiling case studies of incidents where individuals were found to have altered their fingerprints, 2) analysis by investigating the impact of fingerprint alteration on the accuracy of a commercial fingerprint matcher, 3) classifying the alterations into three major categories and suggesting possible countermeasures, 4) developing a technique to automatically detect altered fingerprints based on analyzing orientation field. Experimental results show the feasibility of the proposed approach in detecting altered fingerprints and highlight the need to further pursue this problem.