Height data Porsgrunn 2008

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). 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).高程数据可精细化表征地形与地表特征。该数据通过机载激光扫描（airborne laser scanning）或航空影像（aerial images）匹配生成点云（point clouds）；针对不同应用需求，点云密度（单位：点/平方米）存在差异。基于此类点云，可生成格网格式的数字地形模型（DTM, Digital Terrain Model）与数字地表模型（DOM, Digital Surface Model）。 高程数据可精细化表征地形与地表特征。该数据通过机载激光扫描（airborne laser scanning）或航空影像（aerial images）匹配生成点云（point clouds）。 针对不同应用需求，点云密度（单位：点/平方米）存在差异。 基于此类点云，可生成格网格式的数字地形模型（DTM, Digital Terrain Model）与数字地表模型（DOM, Digital Surface Model）。