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

WorldView‐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 ( DEM s) 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 ) .