[postgis-users] Re: Re: when rasters in Postgis?

[Patrick]

"Gerry Creager" <gerry.creager at tamu.edu> wrote in message 
news:433AD301.9050908 at tamu.edu...
> Current trends in managing those data are to turn entire radar volume 
> scans into HDF or NetCDF files, compatible with JPEG2000.  This is going 
> to be problemmatical however: A radar scan isn't flat but curves above the 
> (apparent flat) surface of the earth in the area around the radar site, 
> resulting in increasing altitude as one gets farther from the radar.

Hi Gerry,

A similar issue arises in NASA's HDF-EOS files that store "swath" data. A 
swath is a number of consecutive passes of a pushbroom scanner on a 
satellite, resulting in an area that is not rectangular nor conformal nor 
anything else. It is essentially just an area along the orbit of the 
satellite projected on the earth's surface. But every scan has the same 
dimensions and the swath is just represented as a SDS (raster for you 
non-HDF folks). The logic of going from SDS/raster to swath is not embedded 
in the data, but you need to know it in order to use the data sensibly.

The same would apply to radar data. I doubt therefore if this would be a 
PostGIS issue, other than maybe implementing a mechanism to flag such 
conditions.

Cheers,
Patrick