Fast color image encryption scheme based on 3D orthogonal Latin squares and matching matrix

To realize real-time image encryption, a fast color image encryption scheme by combining 3D orthogonal Latin squares (3D-OLSs) with matching matrix is proposed. The 3D-OLSs represent that each plane of two matrices must be Latin square and the corresponding planes of the two matrices must satisfy orthogonality. The matching matrix is to produce a matrix orthogonal with the 3D Latin square. In the permutation process, a new 3D permutation method with 3D-OLSs and matching matrix is devised. The proposed scheme could save encryption time to a certain degree, since the orthogonal Latin squares are defined over integers directly. In the diffusion process, to solve the diffuse problem between two planes in the 3D matrix, some matrices of the diffusion process are changed with three variables. Experimental results and security analyses show that the proposed color image encryption scheme has high security, fast speed and could resist various common attacks.