3D point cloud encryption algorithm based on hybrid key and spatial maintenance

With the development of LiDAR technology, 3D point cloud data have a rich information-carrying capacity and environmental perception capabilities, have been widely applied in fields such as the Internet of Vehicles(IoV) and smart homes. However, the privacy and sensitive content contained within them faces significant security risks. To address these challenges, we propose a selective encryption scheme for 3D point cloud based on hybrid key with spatial maintenance. Firstly, a new SH-CCM map is introduced, which exhibits excellent sensitivity to initial conditions, randomness, and unpredictability. Secondly, a hybrid key generation scheme is designed, where the hybrid key is composed of an agreement session key and a user’s private key. Then, a spatial maintenance encryption method is designed using the proposed chaotic map to maintain the spatial stability of the selected regions during encryption, preventing data confusion and loss that could arise from overlap with adjacent point clouds in the encrypted domain. Finally, the security and robustness of this method are verified through simulation experiments and numerical analysis, demonstrating high encryption efficiency and effective resistance against known plaintext/chosen plaintext attacks, differential attacks, brute force attacks, and other statistical analysis attacks.