一种保留特征的网格简化和压缩递进传输方法

Feature-Preserved Progressive Texture-Mesh in Digital Museum

针对数字博物馆中三维藏品网络传输及传输过程中藏品特征保留的需要,提出了一种保留拓扑及纹理特征的网格简化方法,在三角形折叠简化算法的基础之上,通过引入边界三角形和色异三角形等概念,对误差矩阵的计算和误差控制方法进行了改进,保留了原始模型的几何边界和纹理属性等特征信息;并结合递进网格和压缩编码,构造了基于八叉树编码的递进网格文件,从而实现了基于网络的三维模型递进传输系统.

In practice, feature information such as colors, textures, surface normals, etc. is necessary to represent 3D models besides geometry and topology information of triangle meshes. However, with the rapid improvement of 3D capture equipments, the accuracy of 3D models increases and results in the large volume of 3D data. Most traditional methods could not deal with the feature of mesh models such as boundary edges and textures during simplification. So, in order to decrease the data volume of 3D textured models in digital museum and retain significant feature synchronously, a new algorithm of texture-mesh based on triangle collapse is presented. By the concept of geometry and texture boundary, the original meshes are divided to boundary, corner, interior or colory triangles according to different boundary conditions. In this way, the quadric and error criterion is improved, and constraint strategies are adopted to preserve the feature of geometry boundaries and texture attributes during the simplification process. In addition, a method combining octree-based compression with progressive meshes is given to provide a continuous multi-resolution representation of 3D models. The proposed method is successfully applied to progressive transmission and presentation system of 3D models over the Internet.