Local accuracy measures for digital terrain models

Airborne laser scanning and image matching can today form the basis for the generation of digital terrain models (DTMs). In addition to the DTM, quality parameters are needed that describe the accuracy at a high level of detail, at best for every interpolated DTM point. Furthermore, other parameters are of interest, for example, the distance from each DTM point to the data point next to it. This paper presents a method to derive accuracy measures from the original data and the DTM itself. Its application is demonstrated with an example. The quality measures are suitable for informing users in detail about DTM quality and warning them of weakly determined areas.