The Compressing Models And Methods For Map Vector Data By Wavelet Theory

It is very imPortant to conrpress vector maP data on geograPhy environmentsdriulahon, maP database. GIS. This thesis stUdies the comPression of vector mapdata by watelet theoryBased on the properties of vector maP data, the thesis proposed the.comPression models and methods for vector map data by different wavelet basessuch as orthogonal wavelet, B spline wavelet, multi-band wavelet. The boundaryprocessing of wavelet transform and the track of feature points were st'Udied.By the proposed methods of pro-processing data boundary the positions ofthe bountw of data can be maintained very well after the data have beencomPressed.Though the track of the featUre pointS and interpolaton processing, theremove of featUre pointS can be solved.By the different wavelet bases, the comPressed multi-level vector map datacan be obtained, and the data can be used to enlarge and reduce electrica1 maP,building InaP Mase and so on.