基于二叉树的矢量线状要素多分辨率表达与传输  

Representation and network transmission of vector linear feature with multi-resolutions based on binary tree structure

作　　者：蔡志明[1,2] 陈崇成[1] 周旭光[1] 

机构地区：[1]福州大学福建省空间信息工程研究中心/空间数据挖掘与信息共享教育部重点实验室,福州350002 [2]福建工程学院信息科学与工程学院,福州350108

出　　处：《测绘科学》2014年第10期7-12,共6页Science of Surveying and Mapping

基　　金：国家科技支撑计划项目(2013BAZ04329);福建省科技计划项目(2010I0008;2010HZ0004-1);欧盟第七框架国际合作项目(FP7-2009-People-IRSES;247608)

摘　　要：针对目前空间数据网络传输存在用户等待时间长的问题,文章提出了一种改进的道格拉斯-普克(D-P)算法来进行线状要素的化简方法。为了支持数据的快速导出,使用二叉树存储D-P算法的中间结果,并对二叉树进行线性化,以保证空间数据在服务器端得到有效的多分辨率组织;在此结构的基础上,设计并实现了矢量数据多分辨率渐进传输模型和策略;最后通过真实的线状道路数据,分别开展了PC客户端和移动客户端与数据服务器之间的渐进式传输实验,并引进信息熵度量开展了网络数据传输过程中地图信息量的保持分析。试验结果表明该方法能有效地改善用户的体验效果和传输效率。Aiming at the problem of long-time download and the poor experience effect existed in the current network transmission of spatial data,an improved Douglas-Peucker algorithm was proposed for simplification of the linear features.The middle of details of D-Palgorithm was stored in the binary tree in order to support fast data export,the linearization of binary tree was carried out then,so the server could effectively organize the massive spatial data in multi-resolution way.On the basis of this structure,it designed and implemented a progressive transmission model and strategy of multi-resolution for vector data.Finally,the progressive transmission experiments between the PC/mobile client and the data server with real linear path data were given,in addition the information entropy measure was introduced to analyze the map information maintained in the network data transmission process.The results indicated that the method would effectively improve the user＇s experience effect and transmission efficiency.

关 键 词：线状要素 二叉树 道格拉斯-普克算法 多分辨率 渐进式传输 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]