Research On The Digital Watermarking Technique For 3D Polygonal Meshes And Its Application In Digital Museum

Digital watermarking technology provides a new solution in copyright protection and becomes a hot spot in the research field of information security. The bulk of the research on digital watermarks has focused on media such as image, video and text. In contrast, the problem of watermarking on 3D models has received less attention from researchers. The main research work in this paper can be organized as follows:1. This paper presents a robust watermarking algorithm for 3D meshes; the algorithm is based on topology of mesh models. Not only do the 3D mesh models have geometry information, but also the models have topology information. These property make the 3D models different from text, image and video files. We can embed the watermarking into 3D models making use of these properties.2. After analyzing the methods for spatial domain, we proposed a new watermarking algorithm that adds watermarking into a mesh. We get a basic mesh model taking advantage of the progressive mesh simplification algorithm at first. Then the watermarking can be embedded into this simplified model.3. In this paper, we proposed a 3D mesh watermarking algorithm based on spherical parameterization. Firstly, we transformed the 3D mesh into spherical signals using a spherical parameterization. Secondly, spherical harmonic transformation is used to this sphere. Finally, we embedded the watermarking into coefficients of the mesh.4. Using some criteria for 3D mesh watermarking, the robustness of three mesh watermarking algorithms is evaluated, and their range performance are also shown.5. According to the algorithms presented in this paper, we implemented a three-dimension watermarking system applicable to digital museum. This system achieved three mesh watermarking algorithms and got a balance among the quantity of information embedded, robustness and unconsciousness.