An image encryption scheme based on rotation matrix bit-level permutation and block diffusion

• Rotation matrix bit-level permutation and block diffusion are used to encrypt image.
• Confusion operation relies on plaintext against known/chosen-plaintext attacks.
• The scheme is robust against noise and applies to communication on noisy channels.
• The proposed scheme is suitable for running in a parallel computing environment.

This paper proposes a novel image encryption scheme based on rotation matrix bit-level permutation and block diffusion. Firstly, divide plain image into non-overlapping 8 × 8 pixels blocks with a random matrix, then transform each block into an 8 × 8 × 8 three-dimensional (3-D) binary matrix, which has six directions just as a cube. Permutation is performed by multiplying the 3-D matrix by the rotation matrix that relies on plain image according to different direction. Secondly, use block diffusion to further change the statistical characteristics of the image after confusion. Experiment results and analysis show that the scheme can not only achieve a satisfactory security performance, but also have the suitability for a parallel mode and the robustness against noise in communication system.