3D invertible image encryption scheme based on chaotic map

In order to ensure the security of digital image effectively, an image encryption scheme based on chaotic map is proposed. The original image is depicted by a 3D matrix in this paper. First, the 3D matrix is mapped to a 2D bit matrix by using scan-transformation. Then the 2D matrix is stretched to an array, and the array is mapped back to 3D matrix according to fold algorithm proposed in this paper, thus the pixels in the original image are permuted as randomly as possible. Afterward, Lorenz equation is used to generate chaotic sequence, which is used to substitute the elements in the 3D matrix. The designed security key is related with plain image for the sake of enhancing its resistance to known-plaintext attack. Simulation results show that the image encryption scheme has good performance of resisting statistical, and it also has big key space, and it is very sensitive to security key.