An image reconstruction method based on the double-random phase encoding system in the Fresnel domain

A method used to reconstruct the image from the frequency spectrum intensity of an encrypted image is proposed in this paper. The encrypted image is obtained by utilizing the double-random phase encoding technology in the Fresnel domain on a symmetrical original image. The frequency spectrum intensity of an encrypted image is received by a CCD, and transformed to a computer. With the help of an algorithm, involving autocorrelation and complex-convolution in the discrete Fresnel transform, a reconstructed image that is the same as the original image could be obtained. Numerical simulation shows that our method is only effective for a symmetrical original image. Discussion on the influence of the deviation of pixel value in the position of symmetry has also been provided in this paper.