A NEW WEB-BASED GEO-INFORMATION SERVICE APPROACH WITH DIGITAL MEASURABLE IMAGE TOWARD DIRECT VIRTUAL REALITY

摘要

A new web-based geo-information service approach with digital measurable image (DMI) from direct dereference system is proposed to construct the geo information infrastructures for the web service on web 2.0 ear. Firstly, the requirements of geo-spatial information are described facing to the next generation of internet and Web 2.0. The geo information service technique architecture and its requirement is designed for the new web service mode which different to the traditional web GIS architecture. Ajax, SVG, GML and grid technique together with web service development is proposed to make the geo information visible, measurable and minable via internet. And the requirements of geo information data are summarized with the measurable geo-referenced images from land based mobile mapping system. A new concept of digital measurable images is proposed for the geo information service. Secondly, the related technique for data acquisition, organization and management for DMI is proposed. Land based mobile mapping system with over than 8 cameras and DGPS/IMU integrated sensors is designed to collect the DMI for the geo information service. Data collection procedure and related quality control methods are designed to obtain high quality DMI. A unique geo coding algorithm is proposed to handle huge volume DMI images via internet with a query response within 0.2 second. The unified database integrated DMI with existing 4D products (DEM/DOM/DLG/DRG) are described. Based on these techniques a new geo-spatial information service system-DMI based location based service is set up to improve the quality of geo information service. The geo information service with DMI can obtain a direct and fast visualization with the geo spatial data which is different to the traditional 3D model construction to realize visualization toward a direct virtual reality. Finally, the appliatability of DMI based geo-information service system is briefly discussed for business to business and business to customs service. A prototype is developed to verify the new approach on the web 2.0.