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Analysis of out-of-focus blur influence on fingerprint liveness detection system

Fingerprint identification system is widely used in various areas. However, a fake fingerprint made from a mold can cheat the identification systems easily. It reduces the reliability of the identification system. Recently, fingerprint liveness detection methods are proposed to filter fake fingerprints before the verification process. Although some liveness detection methods have satisfying performance, to best our knowledge, there is no investigation on the fingerprint images with out-of-focus blur which is a common scenario, especially for the touchless sensors. In this paper, we simulate out-of-focus blur on the fingerprint images and study their influence on the performance of state-of-art liveness detection methods. The resultindicates that the accuracy on classifying the fake fingerprint images with out-of-focus blur drops significantly, which may lead to secure problems.