Height data Froland 2012

Elevation data provides a detailed description of terrain and surface. The data are established as point clouds from airborne laser scanning or matching from aerial images. The point clouds have varying density (point/m²) for different purposes. From the point clouds, elevation models are generated on grid format of terrain (DTM) and surface (DOM).高程数据可对地形与地表进行精细化描述。此类数据通过机载激光扫描或航空影像匹配技术生成点云（Point Cloud）数据。不同应用场景下，点云的密度（单位：点/平方米）存在差异。基于上述点云，可生成针对地形与地表的格网格式高程模型，即数字地形模型（DTM, Digital Terrain Model）与数字地表模型（DOM, Digital Surface Model）。