Optics and Lasers in Engineering | 2021
Security analysis on optical image hiding with silhouette removal based on the interference
Abstract
Abstract In this paper, the security of the cryptosystem with three phase-only masks (POMs) based on the interference has been evaluated. The security strength of the classical interference-based cryptosystem with two POMs has been enhanced by employing a random phase distribution to generate three POMs. This random phase distribution is utilized not only to replace the partial part of two POMs which could be used to retrieve information of the plaintexts directly, but also to modulate and generate an additional POMs; thus, the silhouette problem could be eradicated and key space would be enlarged. It is shown that the security strength of the interference-based cryptosystem has been improved; however, the random phase distribution is irrelative to the plaintexts and two POMs are dependent. Based on this finding, hybrid attacks including a known-plaintext attack (KPA) and phase-retrieval technique-based processes with different constraints have been proposed to crack the interference-based cryptosystem with three POMs and to release its silhouette problem. Numerical simulations have been carried out to validate the feasibility and effectiveness of the proposed attacks.