Research On 3D Model Data Protection Algorithm Based On Secret Sharing

The rapid development of computer and information technology has promoted the wide application of 3D models in various fields(including manufacturing,entertainment,and even military fields).Therefore,the data security and copyright protection of 3D models have also attracted more attention,In order to prevent illegal users from embezzling three-dimensional model data and illegal access to its content,.Based on the secret sharing and digital watermarking technology,this thesis deeply studies the data characteristics of the 3D model,and proposes a 3D model sharing algorithm based on secret sharing and an invisible 3D model blind watermarking algorithm,which realizes the security protection of 3D model data and copyright.The main work of this paper is as follows:First,a 3D model sharing algorithm based on feature point selection is proposed.The algorithm first selects a feature point from all the vertices of the original 3D model;then uses Shamir's threshold secret scheme to share each feature point as a sub feature point,and replaces the original feature point of the3 D model with the sub feature point to form a shared feature point Three-dimensional model;finally,the shared three-dimensional model is randomly assigned to each participant to save.Since the shared sub-feature points change the value of the original feature points,the structure of the generated shared 3D model is changed,and this change protects the security of the original 3D model data.During the reconstruction process,at least one participant is required to provide the shared 3D model held by them before the original 3D model can be restored without damage.The experimental results also further verify the feasibility and effectiveness of the proposed algorithm.This kind of sharing algorithm,on the one hand,helps prevent data leakage caused by over-concentration of ownership,and on the other hand,it can also ensure the security and integrity of the original 3D model.Second,a blind watermarking algorithm for invisible 3D models based on secret sharing is proposed.The algorithm first uses Shamir's threshold secret sharing scheme to share the copyrighted watermark image to generate a secret image.In the embedding process,the three-dimensional model is converted into a spherical coordinate representation,and by changing the distance from part of the vertices to the center of gravity of the model,less than the number of secret images are embedded in the model.The extraction process is the inverse process of the embedding process,but at least a secret image is required to completely restore the original watermark image.Experimental results show that the proposed blind watermarking algorithm can resist attacks such as noise,grid simplification and affine transformation,and has good robustness and transparency.