A method to achieve color image encryption by using orthogonal compressive sensing and optical scanning holography

A method is proposed for color image encryption by using optical scanning holography together with orthogonal compressive sensing, which can provide distinct keys to different channels of color image, along with synchronous encryption. The theoretical demonstration of orthogonal compressive sensing is prioritized to be narrated, which can produce a preprocessed measurement array for the subsequent sampling. The orthogonal basis matrices may provide an additional key space to guarantee the security of this cryptosystem, and the uncertainty of key is used to make a further illustration. The simulations and discussions are also made on the cyphertext characteristics, the robustness of resisting occlusive attack and some other parameters.