Technical note - Morphological operators to extract channel networks from digital elevation models

The automated extraction of drainage networks includes generation and proce ssing of digital elevation models (DEMs) obtained from the remotely sensed data having stereo viewing capability. The latter aspect generally aims to extract terrain features such as elevation contours and channel networks. I n this technical note, the application of morphological operators to extrac t channel networks from the digital elevation model is described. The metho dology is illustrated using a transcendentally generated DEM that bears the spatially distributed regions in grey levels, assumed as the regions of to pographic reliefs and the V-shaped crenulations in successive elevation con tours. The authors conclude that the adaptation of this approach to extract channel networks from DEM data is straightforward and is simple both algor ithmically and computationally.