Elevation data Image Gjøvik region 2022 part 3

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。该类数据可通过机载激光扫描生成点云，或由航空影像匹配得到点云。此类点云的密度（单位：点/平方米）会因应用需求不同而存在差异。基于此类点云，可生成栅格格式的数字地形模型（DTM，Digital Terrain Model）与数字地表模型（DOM，Digital Surface Model）高程模型。