High-Capacity Reversible Data Hiding in Encrypted 3D Models Based on Secure Multiway Tree Traversal

3D mesh models, as a new form of digital media, are widely utilized in game development, engineering construction, and 3D printing. Recently, there are some reversible data hiding schemes for the encrypted 3D models have been proposed to protect cloud users' privacy. This paper proposes a secure multiway tree traversal based reversible data hiding scheme to further improve performances. First, the secure multiway tree traversal technique is used to traverse vertices and protect the traversal rule. Then, the child vertex is predicted by its parent vertex by MSB prediction and is further compressed by the Huffman coding technique. After model encrypting, some additional data can be embedded on the data hider side. The authorized receiver can extract the embedded data or recover the 3D model. Experimental results demonstrate that the proposed scheme significantly improves the embedding rate compared to state-of-the-art schemes.