Since 1998, COWI India has used special programs for generation of digital elevation models. Through photogrammetric data capture, we create a dataset, which describes the terrain by representative points and lines in three dimensions.

Various application possibilities

The datasets can be used for performing analyses for the telecom industry, conducting landscape analyses, planning and projecting, for making 3D visualization of urban and rural areas as well as calculating noise and assessing visibility.

Use of digital elevation models

Digital elevation models are typically produced as an important basis for design and construction of infrastructure such as roads and railways. Use of the photogrammetric method also overcomes problems of accessibility otherwise posed by difficult terrain.

In connection with excavations, open-cut mining and preparation of waste disposal sites, repeated measurement of digital elevation models can document alteration of the terrain and changes in volumes can be calculated.

From a digital elevation model, a number of digital and graphic products can be derived, such as:

• Interpolation of height at any terrain point. 
• Plots of contours with user-specified contour intervals. 
• Generation of longitudinal and cross section profiles. 
• Plots of isometric and perspective images. 
• Volume calculations, including computation of cut and fill.

Furthermore, a digital elevation model can be included as a part of a GIS/LIS and can thus be applied by many users.