摘要

The majority of encryption schemes based on double random phase encoding usually encrypt one or more plaintext images into a complex-valued ciphertext, which may cause inconvenience of the management, storage and transmission of the encrypted information. This paper aims to develop a real-valued image cryptosystem based on chaotic map and mixture amplitude-phase retrieval in gyrator domain. It can realize encryption for double grayscale images. Firstly, the double plaintext images are perturbed by chaotic maps and then combined into a single-channel architecture through complex representation. Subsequently, an iterative amplitude and phase retrieval process is performed in gyrator domain to determine the real-valued ciphertext and double phase masks. Experimental results have demonstrated the feasibility and security of the proposed scheme. Moreover, the proposed encryption scheme shows better robustness against Gaussian noise and data loss attacks compared with one random phase modulation based scheme.