A Digital Elevation Model (DEM) is a 3D computer graphics representation of a terrain's surface – commonly of a planet (e.g. Earth), moon, or asteroid – created from a terrain's elevation data. A DEM can be represented as a raster (a grid of squares, also known as a heightmap when representing elevation) or as a vector-based triangular irregular network (TIN). The TIN DEM dataset is also referred to as a primary (measured) DEM, whereas the Raster DEM is referred to as a secondary (computed) DEM. The DEM could be acquired through techniques such as photogrammetry, lidar, IfSAR, land surveying, etc.


                                                                                                                                                                                Example of the topographic data from the Shuttle Radar Topography Mission (SRTM).

Created by Tuan Le on 2019/05/21 13:10