A novel multimodal joint information encryption scheme based on multi-level confusion and hyperchaotic map

To achieve efficient and compatible encryption of color-gray multi-image and 3D models, an encryption scheme based on multilevel confusion and hyperchaotic map is proposed in this paper. First, the ISL-HMC hyperchaotic map is employed to generate pseudorandom sequences of the confusing scheme, and its rich dynamical behavior is demonstrated through phase diagrams under different parameters, Lyapunov exponents, and NIST results. Second, the images are subjected to data processing, where multiple color-gray multi-size images are merged into a single image and the 3D model is converted into a 2-dimensional matrix. Multi-level confusion is performed next and consists of three parts: pixel point confusion within a 66-pixel block, inter-block confusion of 33-pixel blocks, and confusion of all pixel points. Finally, bi-directional diffusion is performed, which effectively improves the unpredictability and attack resistance of encrypted data. The simulation results demonstrate that the proposed encryption scheme specifies excellent encryption performance and dependability, and is also able to maintain good decryption results. At the same time, the proposed scheme can flexibly handle different models of data, showing excellent compatibility and adaptability, and providing an innovative solution for the secure transmission of multimedia information.