USGS SDTS DEM (*.ddf)
SDTS is a spatial data transfer standard for the dissemination of both vector and raster DEM data from the USGS.
The expected extension is *.DDF.
Compatibility:
- Cadcorp SIS Desktop
- Cadcorp SIS Desktop Express
- Cadcorp SIS ActiveX Modeller
- Cadcorp SIS ActiveX Manager
- Cadcorp SIS ActiveX Viewer
- Cadcorp GeognoSIS