Image Encryption Using Discrete Fractional Transforms

Digital images play an important role, both in daily life applications such as satellite television, magnetic resonance imaging, computer tomography as well as in the areas of engineering, research and technology. So, image security is an important part and issue in information exchange. In this paper, we present encryption of images using discrete fractional transform techniques, discrete fractional fourier transform (DFrFT), discrete fractional cosine transform (DFrCT). These techniques uses cascaded multi stages of discrete fractional fourier transforms with a random phase mask (RPM) at each stage. In decryption, at receiver all the keys and RPM should correctly known to user. Numerical simulations are presented for sensitivity of keys and their effect on mean square error (MSE).