Abstract
Biometric template disclosure starts gaining an important concern in deploying practical biometric authentication systems, where an assailant compromises the database for illegitimate access. To protect biometric templates from disclosure attacks, biometric authentication systems should meet these four requirements: security, diversity, revocability, and performance. Different methods have been suggested in the literature such as feature transformation techniques and biometric cryptosystems. However, no single method could satisfy the four requirements, giving rise to the deployment of hybrid mechanisms. In this context, the current paper proposes a hybrid system for multimodal biometric template protection to provide robustness against template database attacks. Herein, a secure sketch method is first applied to secure the fingerprint modality. Subsequently, a Dual-Tree Complex Wavelet Transform Discrete Cosine Transform (DTCWT-DCT) based watermarking is employed to entrench the fingerprint sketch into the face image. However, a 3D chaotic-map-based encryption method is employed to protect the watermarked facial image in order to offer an added security level. The experimentation performed using the ORL face database and three Fingerprint Verification Competition (FVC) fingerprint databases showed the approach's efficiency in withstanding standard digital image watermarking attacks, brute force attacks, and information leakage. Moreover, the results revealed that the approach achieves high performance, and satisfies diversity and revocability requirements.