Single-shot color image encryption based on mixed state diffractive imaging

We propose a method for color image encryption based on mixed state diffraction imaging. The three channels of the color image, R, G, B, are encrypted together into a single grayscale image by applying the classical optical double random phase mask encryption system, and mixed state decomposition algorithm is employed for the color image decryption, distinctively reducing the complexity of color image encryption with other methods which require to encrypt the color image into three separated channels. To the best of our knowledge, this is the first time that a color image is directly encrypted into a single grayscale encoded image. We have demonstrated the feasibility and high security of the proposed method with computer simulations.