Comparison of the Resampling Methods for Gridded DEM Downscaling

Abstract

In this paper, a comparison and evaluation of three resamplingmethods for gridded DEM is implemented. The evaluation was based onthe results of bilinear resampling, bi-cubic and Kriging resamplingmethods for an experiment using both degraded and sampled datasets at 20m and 60 m spatial resolutions. The evaluation of the algorithms wasaccomplished comprehensively with visual and quantitative assessments.The visual assessment process was based on direct comparison of the sametopographic features in different downscaled images, scatterplots andprofiles. The quantitative assessment was based on the most commonlyused parameters for DEM accuracy assessment such as root mean squareerrors (RMSEs), linear regression parameters m and b, and correlationcoefficient R. Both visual and quantitative assessment revealed greateraccuracy of the Kriging over the other two conventional methods.