3 ms·
You can already do this fairly easily; 1) Download the SRTM elevation datasource for the region you're interested: http://e4ftl01.cr.usgs.gov/SRTM/SRTMUS1.003
by danpat 12y ago
You can already do this fairly easily;
1) Download the SRTM elevation datasource for the region you're interested:
http://e4ftl01.cr.usgs.gov/SRTM/SRTMUS1.003/2000.02.11/ http://e4ftl01.cr.usgs.gov/SRTM/SRTMUS1.003/2000.02.11/
2) Load the .HGT files into PostGIS using raster2pgsql:
http://postgis.net/docs/using_raster_dataman.html#RT_Raster_Loader http://postgis.net/docs/using_raster_dataman.html#RT_Raster_...
3) Run your queries, relatively simple:
SELECT ST_Value(elevationraster, Point(51.123,-91.123)) FROM elevation_data;
- cullenking 12y agoSee my above comment for a library that requires no geospatial database, just DEM files in gridfloat format. By recording information about each gridfloat file (bounding box, cellsize in lat/lng) you can do some simple math and only one disk operation (in the optimal case) to get an elevation value. Even with my crappy code in the library I mentioned in the other comment, the service is very fast on even spinning disks.