Secure Color Image Encryption using OpticalTransformations

Abstract

This study presents a novel approach for encoding and decoding colour imagesby combining the Arnold Transform, Discrete Wavelet Transform (DWT),Singular Value Decomposition (SVD), and the fast walk Hadamard transform(FWHT) process. The encoding process involves using clusters of Arnold keysand wavelets, along with singular values of wavelet subbands. The specific calculationsof all wavelet subbands determine the number of Arnold keys and theparameters of the fast wavelet Hadamard transform. To evaluate the effectivenessand robustness of the proposed technique, the average squared deviationand the ratio of the peak signal power to the power of the noise are used. Theresults show that energy is conserved when employing fast Walsh Hadamardtransforms, and the encrypted image can be compressed effectively. Thus, thismethod offers a secure and efficient approach for transmitting colour imagesover both secure and unreliable communication channels.