Optical Image Encryption Based on Chaotic Palmprint Phase Mask and Phase-Shifting Digital Holography

In our study, we introduce an innovative optical grayscale image encryption approach that leverages chaotic palmprint phase masks (CPPMs) in conjunction with a PSDH technique. Within this method we are putting forth, the chaotic palmprint phase masks are produced by the palmprint using chaotic method and the SHA. Throughout the procedure, that involves transforming the original grayscale image into three distinct noise-like holograms. This transformation is achieved by utilizing CPPMs positioned at various Fresnel diffraction distances and employing a PSDH technique. Throughout the decryption procedure, the original grayscale image can be reconstructed using the right secret keys, such as the right palmprint, chaos parameters, and Fresnel diffraction distances. Numerical experiments have demonstrated that the suggested encryption method exhibits strong sensitivity to secret keys and is capable of withstanding noise-based attacks.