The Study of 3D Digital Watermarking Algorithm Which is Based on a Set of Complete System of Legendre Orthogonal Function

As for the Encryption protection of 3D digital model, 3D digital watermark technology is inevitably the preferred plan. However, due to the curved surface property and three-dimension property in 3D model itself, there are no better plans that can effectively defend all kinds of watermark attacks among the numerous 3D digital watermark algorithms so far. Thus in this paper a modified algorithm will be proposed, which uses a set of complete system of Legendre orthogonal function to conduct the transformative processing to the geometry information of the digital model and embed the watermark into it. The system is a normal complete orthogonal function constituted by Legendre polynomial of times which not only shares the same property with the smooth orthogonal function system but also has the same property of discontinuous orthogonal function system. Therefore, from the result of the test we can see that the algorithm has strong invisibility, stability and robustness, which greatly enhances the security and the reducibility of 3D encrypted mode.