Security Augmented Symmetric Optical Image Cryptosystem Based on Hybrid Transform Employing Rear Mounted Technique Using Three Different Complex Masks

Abstract

This paper presents the utilization of the novel rear mounted triple phase masking procedure to increase the security of traditional double random phase encoding (DRPE) scheme with a variation of hybrid transform. Two chaotic random phase masks and a deterministic phase mask are used in the scheme to enhance its security as opposed to traditional DRPE which uses random phase masks. From the previous studies on cryptanalysis of DRPE, it is clear that the second lens used in it proves to be irrational which leads to cryptanalytic attacks on DRPE. The enhanced framework discards the invalidation of the second lens and therefore reinforces DRPE security. The hybrid transform is a combination of fractional Hartley transform and Gyrator transform that improves the quality of the cryptosystem. The carried out simulations exhibit the efficacy of the designed symmetric cryptosystem.KeywordsChaotic random phase maskDeterministic phase maskFractional Hartley transformGyrator transformRear mounted triple phase masking