DIGITAL ELEVATION MODEL DATA-ANALYSIS USING THE CONTACT SURFACE-AREA

We present an approach for analyzing digital elevation model (DEM) dat a using the concept contact surface area and mathematical morphology, DEMs are digital representations of the Earth's surface. Generally spe aking a DEM is generated as a uniform rectangular grid organized in pr ofiles. In order to analyze DEM data by means of binary morphology, th e models are represented as binary solids composed of regular polyhedr ons (voxels). In the content of this work, we use morphological operat ors to erode DEMs, simplify binary solid data, preserve essential shap e characteristics, understand shape in terms of a decomposition, and i dentify object features. This is shown by means of some simple example s. We define the contact surface area for DEMs composed of voxels. The contact surface area corresponds to the sum of the contact surface ar eas of the neighboring voxels of DEMs. A relation between the area of the surface enclosing the volume and the contact surface area is prese nted. The definition of contact surface area permits us to obtain a fa st and efficient method for plotting models composed of a large number of voxels. (C) 1998 Academic Press.