A ground filtering algorithm for airborne LiDAR in consideration of terrain break lines

It's difficult to preserve terrain features, such as escarpments, terraces or terrain break lines, in filtering LiDAR data in mountain areas. According to the characteristics of LiDAR data in mountain areas, three important aspects of TIN filtering algorithm are improved: I more seed ground points are selected using a random strategy; II a new ground criteria called predicated terrain angle is proposed for preserving terrain break lines; III attaching a priority to each point and adjusting it during filtering, then points with higher priorities will be judged earlier. At last, some experiments on LiDAR data in mountain areas are made to verify the validity of the proposed method. Results show that the proposed method is very effective and useful for preserving terrain features and for improving the quality of filtering. ©, 2015, Wuhan University. All right reserved.