Colour image encryption scheme based on the real-valued discrete Gabor transform

Abstract

A new colour image encryption scheme that combines real-valued discrete Gabor transform (RDGT), 3D chaotic system with bit scrambling is proposed. First, the plaintext image is performed by the real-valued discrete Gabor transform. Subsequently, the transformed image undergoes Arnold transform to disorder bit values, and the coefficients of Arnold transform are selected from the chaotic sequence. Finally, the processed image matrix is XORed and scrambled with the 3D chaotic sequence after cyclic shift operation. The proposed algorithm possesses a large key space, and the keys are related to the plaintext image. Since the correlation of the ciphertext image is significantly smaller than that of the original image, the performance of the proposed algorithm is acceptable. Simulation results and performance analyses illustrate that the proposed colour image encryption scheme is feasible and secure.