Extraction of Stream Channels in High-Resolution Digital Terrain Images Using Morphology

Our paper proposes an approach for the extraction of stream channels from airborne laser swath mapping (ALSM) data. Recent advances in technology have led to high-resolution topographic data acquisition by means of ALSM yielding digital elevation model (DEM) datasets with horizontal resolutions of lm and a vertical accuracy of 0.15 m. We apply morphological operations on an ALSM DEM to detect stream channels. The results are compared with an existing terrain analysis tool known as TauDEM. Tools like TauDEM use morphology over large-scale areas but they often fail in detecting stream networks over small-scale areas. The proposed method uses small-scale morphology to provide complementary results for streamline locations over a small catchment area.