A three-layer quantum multi-image encryption scheme

In this paper, a new quantum representation for multiple images (QRMI) is presented, which can save more storage space than the existing representations. Moreover, to improve efficiency and security, a three-layer quantum multi-image encryption scheme is proposed based on QRMI. First, in the position-layer scrambling phase, the 3D non-equilateral Arnold transform is used to scramble the pixel position and sequence number of images, which is equivalent to achieving the 3D pixel position scrambling at one time. Then, in the bit-layer permutation phase, a bit-plane permutation operation is conducted to exchange the bit-plane order. Finally, in the pixel-layer diffusion phase, 3D hyper-chaotic Henon is used to generate three key sequences, and the bit-layer permutated image is XORed with the quantum key image originating from those key sequences to obtain the ciphertext image. The corresponding quantum realization circuits are given, and simulation results show that the proposed quantum multi-image encryption scheme is effective and secure.