[postgis-users] SRTM data

[Brent Wood]

Bruce Bushby wrote:
> Hello
> 
> I'm hoping somebody on the list has some SRTM data experience and would
> be willing to share a few pointers?
> 
> I have downloaded various SRTM datasets (GTOPO30, SRTM30, SRTM1 and
> SRTM3). Is it possible to extract coordinate/height data and import into
> PostGIS? 
> 
> I've done a fair amount of research but I can't seem get my head around
> DEM, GeoTiff and Binary Rasta. Also, most of the searching suggests that
> the data can only be imported as a BLOB, in which case one doesn't need
> PostGIS. This further confuses me because Grass can import the data and
> generate Topo maps which are all about coordinates/Height.
> 
> Any tips and pointers much appreciated.

I've done this using GMT. There are a few ways to turn SRTM (or pretty much any
gridded or non-gridded) data into GMT compatible netCDF files, including GMT
commands, GDAL & GRASS. Once into this format, GMT can export the XYZ values or
generate line features (contours) which can be reformatted into PostGIS lines.

Right now this reformatting is not trivial, unless you are a reasonable
Perl/python/etc scripter :-), but I hope to have OGR support for reading &
writing GMT format data shortly, which will make this much easier.


Cheers,

  Brent Wood