Automatic thresholding for shadow removing based on NGATE DSM

Tree cover is one of the important forest parameters in SWISS National Forest Inventory (NFI). Therefore, automatic tree cover detection is of practical interest. However, it difficult to remover shadow areas because of some effects related to ADS40 data processing of Digital Surface Model (DSM) by NGATE. This paper proposes an automatic and flexible threshold selection algorithm for shadow removing based on the mean-shift segmentation results. Experimental results show that the shadows can be successfully removed by the proposed algorithm.