Research On Data Model Of3D Video GIS

VideoGIS is an extension of conventional MultimediaGIS that is making the retrievaland interaction come true between each other through integration of video images andgeographical location data, which is applied in traffic management, video surveillance and otherfields. Most of the current videoGIS systems combine video and2DGIS in the applications.Withthe improvement of people’s cognitive levels around the world and the progress of IT technology,social demand is also more than content to see the world from the sky, also not content to just usesimple abstract symbols to understand the world, which inspires popular expression increased.Thus, that these new positioning media (such as the geographic video, panoramic photos andmeasurable image) and multimedia geographic hypermedia (such as integrated Web, GIS, andgeography of video) can provide new multimedia geographic expression. However, at the sametime, video GIS will lead users to the confused situation, making it difficult to have acomprehensive understanding of the world around us.3DGIS guides users make more objective,authentic description of the real world, making themselves have the feeling of being personally onthe scene. However, it also faces many challenges and problems,such as large amount of data anddifficulty in modeling. Combined with the advantages and disadvantages of them, in this paper, itwill integrate geographic video to three dimensional space, design geographical video3D datamodel, research the retrieval methods, and finally realize the video GIS prototype system underthe three dimensional space.On the basis of in reviewing of the research progress of review video GIS and3D GIS and in summary of the integration of the two mixed methods, this paper achieves athree-dimensional video GIS solution:(1) It defines geographical video object and semanticdescription,designs stereo video data model and data retrieval method,and mplements thegeographical video data organization in three-dimensional space;(2) Based on the design of datamodel, are analyzed in detail based on the spatial location and the significance of the datainformation retrieval method, and retrieve the expression in the SQL language;(3) Taking HenanUniversity for example, it develops the three-dimensional video GIS prototype system, based onOpenSceneGraph and OpenCV, it has built the3D VideoGIS,which we has accomplished thefunctions of the geography video play and spatial retrieval, we can validate the design data modeland data retrieval method in our study.The design and Realization of3D video GIS shows that:(1)the data model adopted inthe study satisfies the expression of the geospatial information, which provides a more practicalsolution for the interaction between the video images and unit of geographical spatial object at thesame time.(2)Three dimensional space established by using OpenSceneGraph3D softwaredevelopment kit satisfies the possibility of a lateral view of the world. The addition of video datamakes the system more close to the demand.(3) the implementation of this system provides asolution to the application of video GIS to highway, urban management, tourism management andriver regulation and other fields.This paper includes six chapters: the first chapter Introduction discusses the researchbackground, research contents, research significance and the research target about the3D videoGIS system, etc. The second chapter is the literature summary which reviews Expression ofgeography, video GIS and the research progress of3D GIS system, and summarizes the solutions to the video GIS. Chapter three is data model design, where it analyzes the basic theory of videoGIS,3D GIS and related technologies, and relates3D video data model that will be adopted infuture work. The fourth chapter for geographic video3d databases and its retrieval, using SQLlanguage defines the different methods of data retrieval.The fifth chapter introduces thedevelopment of video GIS system, makes a detailed description of the main module realizationprocess, and verifies the feasibility of the system. The sixth chapter is about summary andoutlook,where it summarizes the research results of this study, relates the innovations andshortcomings of the study, and gives a look into the future perspective.