An Approach to Reduce Boundary Distortion in Compressing Grid Dem with Wavelet Transform
نویسندگان
چکیده
Digital Elevation Model (DEM) is the core data for three-dimensional visualization and geographical spatial analysis. With the implementation of Digital Earth, the amount of various DEM data is rapidly expanding. In order to compress DEM data, researchers ever put forward two kinds of DEM compression methods: Generic entropy encoding compression; Converting grid DEM to TIN DEM [1][2]. In recent years, a great progress has been obtained in the investigation of compressing DEM data with wavelet transform [3]. However, there is still a sticky problem in wavelet transform, i.e. the boundary distortion, needed to be solved. 2. BOUNDARY DISTORTION IN WAVELET TRANSFORM
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