Abstract
In this paper we propose a watermarking based two-stage authentication framework to enhance biometric system security. The face feature of one individual is embedded into his/her fingerprint image as credibility token. During authentication, the watermark is first extracted to establish data authenticity. If legitimate, the face pattern can further serve as supplemental trait in biometric authentication progress. A wavelet quantization based watermarking method is proposed to robustly embed information in fingerprints while preserving their discriminating features. Meanwhile, a sparse representation based classifier is adopted to efficiently exploit the identity information within face watermarks. Experimental results which evaluate both watermarking and biometric authentication performance demonstrate the effectiveness of this work.