自发地理信息兴趣点数据在线综合与多尺度可视化方法

A Real-time Generalization and Multi-scale Visualization Method for POI Data in Volunteered Geographic Information

移动及Web环境下,集成各种自发地理信息POI数据与地理框架背景数据的混搭式地图应用,越来越多地出现在主流地理信息平台及LBS服务中。由于缺乏适宜的在线多尺度可视化机制,这种POI数据表达上通常出现拥挤、压盖等冲突现象。针对该问题,本研究将传统的尺度变换方法与在线环境相结合,提出一种面向城市设施POI数据的多尺度可视化策略。即由服务器端通过预处理方式对POI数据进行多层次结构化组织;在此基础上,客户端依据显示比例尺导出对应层次的POI目标,并通过移位操作解决局部存在的符号表达冲突现象。试验表明,该方法符合数字化网络应用的在线实时需求,同时也能获得较高质量的多尺度表达效果。

With the development of mobile and Web technologies ,there has been an increasing number of map‐based mashups which display different kinds of POI data in volunteered geographic information .Due to the lack of suitable mechanisms for multi‐scale visualization ,the display of the POI data often results in the icon clustering problemwith icons touching and overlapping each other .This paper introduces a multi‐scale visualization method for urban facility POI data by combing the classic methods of generalization and on‐line environment .Firstly ,we organize the POI data into hierarchical structure by preprocessing in the server‐side ;the POI features then will be obtained based on the display scale in the client‐side and the displacement operation will be executed to resolve the local icon conflicts .Experiments show that this approach can not only achieve the requirements of real‐time online ,but also can get better multi‐scale representation of POI data .