Open Collections

Abstract

Two shortcomings of systems developed to automatically extract the topographic features of terrain are that feature definitions are often based on a single attribute, such as Gaussian curvature or slope, and that interactive queries regarding the similarity of one region to another are rarely supported. We report on a prototype system for triangulated terrain models that attempts to address these two issues. It supports interactive classification of the terrain via a user-controlled classification system. Each classification category is defined in terms of ranges of five key terrain attributes: local relief, slope aspect, slope gradient, plan curvature and profile curvature. The system also supports queries of the type: "Which regions are topographically-similar to the selected region?" We use optimal-monomorphism in attributed graphs so that "topographically-similar" goes beyond simply matching terrain attributes to include the attributes and spatial relations of adjacent regions.