Maarten, If you use GlobalMapper to export the elevation to GeoTIFF, make sure you select Elevation from the File Type list on the GeoTIFF Export Options, otherwise it exports it as a color-coded image. GDAL/Mapserver will then be able to read the 16-bit integer (or 32-bit float) data GlobalMapper exports.
If you don't want to use GlobalMapper and you have .hgt (likely SRTM data?), you can create an .hdr header file for each .hgt file so GDAL/Mapserver will load them, or you can wait for GDAL 1.5.0 to be released (it can read them without header files). Brent Fraser GeoAnalytic Inc. Calgary, Alberta ----- Original Message ----- From: "Maarten Hilgenga" <[EMAIL PROTECTED]> To: <MAPSERVER-USERS@LISTS.UMN.EDU> Sent: Monday, November 26, 2007 3:22 AM Subject: [UMN_MAPSERVER-USERS] getting elevation data from mapserver > Dear all, > > I'm trying to output elevation data in dem format as described in the > WCS server example. The elevation data is in dted format (hgt file). > Since gdalinfo doesn't recognize this file as useable, I've used > global mapper to convert it to geotiff. The geoTiff is 1201x1201 and > has three bands: > > Band 1 Block=1201x1 Type=Byte, ColorInterp=Red > Band 2 Block=1201x1 Type=Byte, ColorInterp=Green > Band 3 Block=1201x1 Type=Byte, ColorInterp=Blue > > The output from mapserver is 800 x 600 and has three bands as well, > > Band 1 Block=800x5 Type=Int16, ColorInterp=Gray > Band 2 Block=800x5 Type=Int16, ColorInterp=Undefined > Band 3 Block=800x5 Type=Int16, ColorInterp=Undefined > > When I load the resulting file as geotiff into global mapper, I get a > black image. The height of the whole map is at least 1000m. Does > anyone know how to display this elevation data? Could it be that the > elevation is first converted to 8 bit and then to 16? > > TIA, Maarten
