== DEM scripts ==
This page details and explains the use of the DEM creation scripts:
   '''lidardem.sh'''[[BR]]
   '''asterdem.sh'''[[BR]]
   '''nextmapdem.sh'''[[BR]]
   '''lidar_aster_dem.sh'''
The scripts listed are written in bash.

These scripts are used to create a DEM from LiDAR and elevation model tiles. 
The scripts use grass GIS to read in the elevation tiles and perform patching and various other operations on the data to create a DEM.
GRASS is a GIS (Geograohic Information System) and details of it can be found at: http://grass.fbk.eu/. There is a detailed api and usage guide, it is available for free download at: http://grass.fbk.eu/download/index.php.

=== Creating a DEM from ASTER data using ''asterdem.sh'' script ===
ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) is a sensor on the Terra satellite, ASTER is partly being used to obtain elevation maps. The ASTER version 1 have an approximate resolution of 30 metres, version 2 however has an approximate resolution of 15 metres.
[[Image(http://arsf-dan.nerc.ac.uk/trac/attachment/wiki/Help/DEM_scripts/15_metre.jpg)]]