Research On Digital Watermarking Algorithm Based On 3D Point Cloud Model

The rapid development of three-dimensional media digitization makes the three-dimensional point cloud model play an irreplaceable role.However,digital media such as 3D point cloud model is easier to copy,and its copyright protection and authority authentication issues are increasingly prominent.At present,digital watermarking technology is widely and effectively applied to solve such problems.In this paper,the digital watermarking technology of three-dimensional point cloud model is studied and discussed.The results obtained are as follows:A watermarking algorithm for 3D point cloud model based on vertex curvature is proposed.The algorithm selects the vertices with larger root mean square curvature of the model as the candidate vertices for watermark embedding,because such vertices are usually located at the deeper position of the model,which can provide good concealment for the watermark information.At the same time,the non-candidate vertices are used to establish invariant space to enhance the robustness of the algorithm.In the process of watermarking embedding,watermarking is embedded by changing the radial distance of candidate vertices in different global rings.The number of embedded watermarks in each global ring is determined by the number of candidate vertices scattered into the global ring.The process of watermarking extraction does not need the original model.It is a blind watermarking extraction scheme.The ex perimental results show that the proposed algorithm is robust to the geometric attack of the model under the premise of ensuring the invisibility of the watermark.A watermarking algorithm for 3D point cloud model based on feature vertex localization is proposed.The algorithm uses the normal relationship between the model vertex and its 1-ring domain vertex to select feature vertices.The number of feature vertices is determined by the watermark capacity.In the process of watermarking embedding,according to the longitude of the model,the point cloud model is divided into several longitude regions.The watermarking information is embedded by modifying the azimuth angle of the feature vertices within a certain longitude range,while the azimuth angle of the non-feature vertices remain unchanged.The two strategies of region embedding and redundant embedding watermarks make the algorithm achieve a good balance between watermark invisibility and robustness.Watermarking extraction is a blind watermarking extraction scheme.The experimental results show that the algorithm resists rotation and simplifies geometric attacks with strong robustness in the case of good watermark invisibility.