Shift-tolerance property of fully phase encryption that uses a joint transform correlator

We technically investigate the robustness of an image encryption technique that uses a virtual phase image and a joint transform correlator (JTC) in the frequency domain. An encrypted image is obtained by the Fourier transform of the product of a virtual phase image, which camouflages the original image, and a random phase image. The resulting image is then decrypted by use of a decrypting key made from the proposed phase assignment rule in order to enhance the level of security. We demonstrate that the encrypted image generated by the proposed JTC-based decryption technique is robust to data loss and image shift.