Multiple color information cryptosystem using Hessenberg-decomposition-modulated chaotic and face biometric phase encoding

Abstract

A novel, to the author’s knowledge, multiple color information cryptosystem based on Hessenberg decomposition (HD)-modulated chaotic and face biometric phase encoding is introduced. The face biometric phase mask (FPM) and chaotic phase mask (CPM) are modulated by HD to obtain an upper Hessenberg matrix, an upper triangular matrix, and two unitary matrices for the first time. Each original color image is decomposed into R, G, and B channels. Each channel is individually modulated by an upper triangular matrix and two unitary matrices. The upper Hessenberg matrix and modulated R, G, and B channels are inverse discrete wavelet transformed to produce a fused image. In the same way, fused images for multiple color images are generated and combined into a single complex image, which is bonded with a first chaotic face biometric phase mask (CFPM) and fractional Fourier transformed. The resultant image is amplitude- and phase-truncated to generate the first common decryption key and preliminary encrypted image. The encrypted image is bonded with a second CFPM and fractional Fourier transformed. The obtained image is amplitude- and phase-truncated to generate the second common decryption key and final encrypted image. The proposed method utilizes the fused image as a covered image to conceal the modulated R, G, and B channels of each original color image. Furthermore, six decryption keys (three matrix decryption keys, one individual decryption key, two common decryption keys), and six encryption keys (two CFPMs and four orders of fractional Fourier transform) provide resistance against various types of potential attacks. A hybrid optoelectronic system can be utilized to implement the proposed cryptosystem. Numerical simulation results validate the feasibility and efficiency of the proposed scheme.