压缩技术在改善空间数据网络传输的研究

摘要

从当前WebGIS的应用系统结构出发，根据地图瓦片技术应用的特点，从数据压缩和网络传输技术两方面来考虑如何通过减少数据量来提高用户体验，其中前者主要通过剔除PNG文件冗余数据信息，经过无损压缩减少数据本身数据量。而后者则通过GZIP压缩技术，实现在矢量块数据传输之前，对数据先进行动态压缩，再通过网络传输到达目的端后自动解压缩的方法，从而有效减少了网络传输中的数据量，节省了数据传输时间。实验及应用表明，以上两种方法能实际应用中极较好地改善数据传输性能，提高用户体验。%According to the current application of WebGIS system structure and the characteristics of the map tile , this paper mainly considers how to improve the user experience by reducing the amount of data from two ways of the data compression and network transmission technology .The former mainly reduces the amount of data in the data itself by re-moving the PNG file redundancy data information .While the latter uses the GZIP compression techniques firstly to dy-namically compress the vector block data ,then to transmit these compressed data to the destination through the network , and finally automatically decompressed .This method can effectively reduce the amount of data in the network transmis-sion and save the transmission time .Experiments and applications show that the two methods can improve the data trans-mission performance and the user experience .