为进一步优化三角网格模型拓扑编码压缩率,提出一种无损拓扑压缩算法.该算法首先将三角网格模型剖切成图,然后将剖切图表示成三角节点树,将剖切图中的三角带间拓扑结构内蕴在叶子节点、分支节点的邻接关系中,减少了模型压缩时需要编码存储的网格拓扑信息;最后使用顶点的几何信息和最小内角最大原则对三角带内拓扑结构预测,仅对预测错误的元素编码,进一步减少了需要编码存储的网格拓扑信息.与已有的压缩算法对三角网格的遍历编码方式相比,该算法不需要遍历三角网格编码存储,仅需要存储少量网格拓扑结构和预测信息.实验结果表明,该算法处理各类三角网格模型时压缩率有较大降低.
An efficient encoding algorithm for lossless compression of triangle mesh connectivity is presented to further optimize the compression ratio. The algorithm firstly cuts a given mesh into a cutaway graph, then uses a triangle nodes tree to present the graph, containing the triangle strips topology information on the graph in the adjacency relationships between the leaf nodes and the branch nodes, reducing the mesh topology information needed to be encoded. Finally, we use the minimum interior angle maximum principle to predict the internal topology of the triangle strips, only encoding the prediction error elements, thus further reducing the information needed to be encoded. Compared with the current compression algorithms, this algorithm does not traverse the triangular mesh, only encoding and storing a small amount of mesh topology information and prediction information. Experimental results show that the algorithm can greatly reduce the compression ratios and process various triangle meshes.