A high-resolution DEM-based method for extracting canals

In this paper, we present a method for extracting area features of canals using high resolution Digital Elevation Model (DEM) based on geometry from analysis on section lines. The method includes four steps: (1) plotting section lines in four certain directions, (2) segment the section lines according to their tendency, (3) determine the candidate feature points according to the segments in step 3 on four different directions separately, and (4) extract final canal feature points using the combination of candidate feature points on four directions. This paper also applies this method to extracting canals in a floodplain in Dongting Lake Basin. Experiment results show that our method is appropriate for extraction of area features of manual canal systems in plain area. Besides, we analyze this method´s sensibility to DEM horizontal resolution by comparing the extraction results from three DEM data with different horizontal resolution.