Height data NDH Levanger 5pkt 2017

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（Elevation data）可对地形与地表进行精细化描述。该类数据可通过机载激光扫描生成点云，或经由航空影像匹配获取点云。 此类点云的密度（单位：点/平方米）因应用需求不同而存在差异。 基于此类点云，可生成地形（DTM，Digital Terrain Model）与地表（DOM，Digital Surface Model）的栅格格式高程模型。