Design and implementation of WebGIS-based digital Yang Zhou information system

In this paper, a B/S structured WebGIS-based information system of Yang Zhou city is designed and developed by integrating various data sources including aerial photos, video clips, digital pictures etc. Special focus is cast on hierarchical data structure, image pyramid, image compression and online dissemination technology in order to efficiently process and distribute the over all 700M high resolution aerial photos of the city area. The system can automatically display the exact area with the most appropriate resolution as a response to the user´s operation at browser end. Also the integrated raster-and-vector Web publishing technology is utilized thus to simultaneously display necessary map legends and text notes at the according location on the aerial photo cover. The experimental results show that the system can satisfyingly meet the need of real-time map display and smooth roam of large data volume with the most proper resolution under present computer hardware configuration, network bandwidth and transfer speed thus to set a good example of WebGIS-based mass data online service