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QGIS: loading elevation layers. Franck Theeten, Royal Museum for central Africa Cabin training 2013. Data format. Elevation data are usually raster data available in 2 formats GRID GeoTIFF ( TIff images file associated to a metadata file giving the position of the image) .
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QGIS: loadingelevationlayers Franck Theeten, Royal Museum for central Africa Cabin training 2013
Data format • Elevation data are usually raster data available in 2 formats • GRID • GeoTIFF (TIff images file associated to a metadata file giving the position of the image)
Accessing files • Free elevation data are availablefrom the STRM (Shuttle Radar Topography Mission) project of the American USGS • 90M data GeoTIFFcanbedownloaded on the website of CGIAR : • http://www.cgiar-csi.org/data/srtm-90m-digital-elevation-database-v4-1
Importing the DEM • Import the (unzipped) DEM GeoTIFF as raster layer (select the tif file):
Importing the DEM • You shouldsee a grey zone thatstillrequires the application fo a colorscheme
Colorscheme • Right click the properties of the layer
ColorScheme • Create 20 Classification zones and click classify:
Colorscheme • Bu double-clicking on the threecolumns, change the value, color and label to the following values (for the exercise)
Colorscheme • Resulting image:
Get information • To get the information about a specific point, select the active layer in the left menu and click on the button • (alsowork for shapefile)
Get information Altitude value in meters