DETERMINATION OF TERRAIN MODELS IN WOODED AREAS WITH AIRBORNE LASER SCANNER DATA

Large-scale terrain measurement in wooded areas was an unsolved proble m up to now. Laser scanning solves this problem to a large extent. In this article, the-characteristics of laser scanning will be compared t o photogrammetry with reference to a big pilot project. Laser scanning supplies data with a skew distribution of errors because a portion of the supplied points is not on the terrain but on the treetops. Thus, the usual interpolation and filtering has to be adapted to this new da ta type. We will report on the implementation of this new method. The results are in accordance with the expectations. The geomorphologic qu ality of the contours, computed from a terrain model derived from lase r scanning, needs to be improved. Solutions are still to be found. (C) 1998 Elsevier Science B.V. All rights reserved.