Martin Spott writes:
> "Norman Vine" wrote:
> > The thing to remember is that PostGIS is just a normal PostGRES 
> > extension module so you still have the power of a general purpose 
> > relational DB to use.
> Correct, but the solution by referring from PostGIS shapes to BLOBs that
> contain the raster data is far not as smart as a 'native' storage
> method for geo-referenced raster data would be.
> I wonder (and I'l love to know because I assume there _is_ a strong
> reason) why the creators of the OpenGIS specs didn't cover raster data
> but only shapes (and their metadata) instead. That doesn't make sense
> to me because the need for a standard interface to raster data appears
> to be as urgent as the interface to vector data. Right ?
> If you'd agree to call PostGIS as sort of an implementation of
> "shapefile in a database", the analogue "geotiff in a database" would
> be nice, too. To other "spatially enabled" database servers cover
> raster data as well ?

This is a popular topic of discussion that is often answerd by 

(1)  BLOB storage is inherently different then Table Storage 

(2) Reprojection of Raster Data is usually *much* more expensive 
     then Vector data and isn't handled by any GIS enabled DB that 
     I am currently aware of.  

     ReProjection capability is a requirement, in fact sort of a definition of  
     the OpenGIS spec. 

For reprojection one can use gdalwarp but I reccomend using OSSIM
esp if one has access to a network or cluster or want an interactive tool
instead of 'batch' mode only. 

I hope to have a lot more to say about networked Raster enabled GIS 
DataBases in a few months :-)



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