Advanced biometric system security: a novel hybrid approach integrating optical asymmetric PTFT and symmetric cipher techniques

The rapidly evolving field of biometric recognition and verification technologies has seen substantial progress recently. However, the storage of biometric data in cloud environments presents significant security challenges, including data theft and unauthorized modifications. Cancelable biometrics emerge as a strategic solution to these issues. This study examines the efficacy of diverse cancelable biometric methods, classified into transformation, encryption, and hybrid approaches. We introduce a novel cancelable biometric system that combines a hybrid optical asymmetric phase truncated Fourier transform (PTFT) with a symmetric cipher scheme, enhanced by a two-level block-based shuffling technique. This innovation improves security through a streamlined shuffling process that divides the PTFT output into four sections for shuffling and an exclusive OR operations with a unique key, enhancing security and computational efficiency. Our empirical evaluation on three distinct datasets (Faces, Iris, and Fingerprints) from FERET, UPOL and CASIA, and FVC2002 DB1 and DB2, respectively, demonstrates superior performance of our system compared to traditional PTFT-based systems. Notable performance metrics include an Area under the receiver operating characteristic curve of 0.9998. Significant improvements were also observed in false acceptance and false rejection ratios, along with more uniform histogram distributions, thereby enhancing randomness in the resultant deformed patterns. From a security standpoint, our system exhibits a high entropy of 7.95 and achieves near-optimal results in the number of pixels change rate and unified average changing intensity, with values of 98.9115 and 23.9755%, indicating robust resilience against potential differential attacks. The research findings, supported by detailed tables and graphical illustrations, underscore the additional security benefits offered by the two-level encryption mechanism.