Double optical image encryption using discrete Chirikov standard map and chaos-based fractional random transform

In this paper, we design a novel discrete fractional random transform based on 2D chaotic logistic maps and two chaotic random masks resulting from Chirikov standard map. Then, a double optical image encryption scheme using discrete Chirikov standard map and chaos-based discrete fractional random transform is proposed. The discrete version of Chirikov standard map is employed to scramble the pixels of two images due to its property of area-preserving. Two scrambled images are regarded as the amplitude and phase of the synthesized input signal. Moreover, with the help of the chaos-based discrete fractional random transform and two chaotic random masks, double random phase encoding is utilized to complete encryption. Numerical simulations demonstrate the effectiveness and the security of the proposed scheme.

► A novel discrete fractional random transform based on 2D chaotic maps is proposed.
► The discrete version of Chirikov standard map is used to scramble images.
► Two random masks derive from Chirikov standard map.
► The proposed scheme integrates the advantages of both chaos and optics.