Abstract
In this paper, we present an interpolating a ground surface method for a Digital Elevation Model (DEM) data based on the Heaviside B-Spline interpolation. To interpolate the DEM data, we modify a Heaviside function used for Heaviside B-Spline interpolation. By calculating the Heaviside function using the elevation value contained in the DEM data, it is possible to obtain the Spline function and an interpolating surface without explicitly giving boundary of sea water bodies, inner waters and void regions. Therefore, our proposed Heaviside function enables interpolating a ground surface including sea water bodies, inland waters or void regions in a DEM data by using a least square method. We show the interpolating results for several DEM data which include elevation discontinuous.
