An Effective Error Resilient Packetization Scheme for Progressive Mesh Transmission over Unreliable Networks

作     者：杨柏林 Frederick W. B. Li 潘志庚 王勋 

作者机构：College of Computer Science and Information EngineeringZhejiang Gongshang University State Key Laboratory of CAD & CGZhejiang University Department of Computer ScienceUniversity of DurhamU.K. 

出 版 物：《Journal of Computer Science & Technology》 (计算机科学技术学报（英文版）)

年 卷 期：2008年第23卷第6期

页      面：1015-1025页

核心收录：

学科分类：08[工学] 080203[工学-机械设计及理论] 0802[工学-机械工程] 

基　　金：Supported by the National Natural Science Foundation of China under Grant No. 60533080 the National Research Foundation for Doctoral Program of Higher Education of China Under Grant No. 20060335111 

主　　题：computer graphics packetization graph partition progressive transmission unreliable network 

摘      要：When a 3D model is transmitted over a lossy network, some model information may inevitably be missing. Under such situation, one may not be able to visualize the receiving model unless the lost model information has been retransmitted. Progressive model transmission offers an alternative to avoid the ＂all or nothing situation＂ by allowing a model to be visualized with a degraded quality when only part of the model data has been received. Unfortunately, in case some model refinement information is missing, one may still need to wait for such information to be retransmitted before the model can be rendered with a desired visual quality. To address this problem, we have developed a novel error resilient packetization scheme. We first construct a Non-Redundant Directed Acyclic Graph to encode the dependencies among the vertex splits of a progressive mesh. A special Global Graph Equipartition Packing Algorithm is then applied to partitioning this graph into several equal size sub-graphs, which is packed as packets. The packing algorithm comprises two main phases： initial partition phase and global refinement phase. Experimental results demonstrate that the proposed scheme can minimize the dependencies between packets. Hence, it reduces the delay in rendering 3D models with proper quality at the clients.