Image Encryption Based on Random Fractional Discrete Cosine and Sine Transforms

We first give a new fractionalization of discrete cosine and sine transforms of types I, IV, V and VIII. The fractional discrete cosine and sine transforms with four random parameters are defined, to which we refer as random fractional discrete cosine and sine transforms. A novel image encryption algorithm based on random fractional discrete cosine or sine transform and random phase encoding technique is then proposed. Numerical Simulation results are presented to verify its validity and efficiency.