Generation and Validation of High‐Resolution DEMs from Worldview‐2 Stereo Data

Abstract

AbstractWorldView‐2 (WV‐2), whose panchromatic images have a 0·5 m ground sampling distance (GSD), was launched by DigitalGlobe in 2009. It is the first commercial satellite to offer 8‐band multispectral imagery with 1·8 m resolution. Due to the off‐nadir sensor rotation of WV‐2, it is feasible to obtain stereo coverage. Digital elevation models (DEMs) have been created with three WV‐2 stereopairs of northern Istanbul with different land types and one of these is comprehensively analysed in this study. A reference DEM, developed from large‐scale aerial photogrammetric mapping, together with a lidar DEM and an overlapping neighbouring WV‐2 DEM, are used for validation. The generated WV‐2 DEM reached, after filtering and in open areas, a standard deviation in height of approximately 1·0 GSD. A higher number of discrepancies larger than 4 m exist than would be expected from a normal distribution, influencing the standard deviation more than the normalised median absolute deviation (NMAD).