Research Of Three-dimensional Modeling Technology And Its Application In Satellite Image System

With the rapid development of imaging technologies and Internet technology, in order tomeet the needs of ever-increasing applications in various industries, the three-dimensionalimaging technology get more and more attention. The three-dimensional scene built with thethree-dimensional imaging technology is not only realistic, but also facilitates the spatial analysis.The three-dimensional GIS technology and the integration technology of surveillance video andthree-dimensional map are not perfect.The three-dimensional spatial data model is not uniform.In this context, the thesis studies the three-dimensional imaging technology and buildsthree-dimensional satellite imaging system. The main contents are as follows:(1) The thesis analyzes the research status and existing problems of three-dimensional datamodeling technology, the three-dimensional GIS technology and the three-dimensional videosurveillance technology. Besides, it describes the significance of the contents.(2)The thesis studies the traditional SPIHT algorithm based on wavelet transform andanalyzes the strengths and weaknesses. This thesis presents an improved SPIHT algorithm: Lowfrequency sub-band and high frequency sub-band are coded with different threshold. Thecoefficients in high-frequency sub-band are encoded with a fixed value. As the experimentalresult shows,the image compressed with the improved algorithm not only has the compressionefficiency as well as the image compressed with the original SPIHT algorithm, but also hashigher quality.Because of the improved algorithm, the three-dimensional satellite imagingsystem accesses data quickly and display images clearly.(3) This thesis analyzes the algorithm of the computer describing three-dimensional model,texture mapping and existing three-dimensional modeling features in geographic informationsystems.This thesis establishes based3D model library. It provides a new method of creating3Dmodels: several simple based3D models are combined into a complex3D model by appropriatemodel matching algorithm. We can construct models with this new method conveniently. (4) The thesis builds3D satellite image database system. In order to build complexthree-dimensional model and calculate data, the thesis establishes the based3D model library,the texture image library, model rendering image library and a variety of data tables. The tablesare mainly used for recording model information, geographic information and user information.(5)This thesis studies the technology of processing map data with the tile technology、thespatial analysis technology and the technology of adding video surveillance data tothree-dimensional map. Considering the characteristics of the geographic information system,the thesis constructs a three-dimensional satellite imaging system with arcgis engine、. NETplatform、ArcObjects development kits.The system has several functions, such as pretreatmentthree-dimensional maps、hierarchical displaying3D map、building three-dimensional model inreal time、importing models to the map、browsing3D space、spatial analysis and playingsurveillance video in the3D map.Finally, we give a summary and propose directions for further work.