Digital Elevation Models as a foundation...

 

Probably one the most important part in the photogrammetric process is the creation of a Digital Terrain Model which is highly dependent on various factors that many people underestimate. A Digital Elevation Model is a generic term associated with a raster of elevation values.

 

 A DEM can be edited to generate a Digital Terrain Model (representation of a bare-earth model that contains elevations of natural terrain features where vegetation, buildings and other non-ground objects have been digitally removed) as opposed to a Digital Surface Model (which contains elevations of natural terrain in addition to top of buildings, trees and any other objects).

 

We automatically generate digital terrain models interpolated from extremely dense 3D point clouds which are extracted from the imagery. Best accuracy is achieved by applying advanced algorithms for image matching and data filtering. The capture of break lines where appropriate is essential to obtain a perfect fit of a DTM with the real-world.