[postgis-users] indexing images stored in PostGres

[Bruce Rindahl]

Paul wrote
>- So you can do raster analysis in the database? I can see the validity 
>in this, for the same reason doing vector analysis in the database is 
>powerful. The database serves as an integration point between vector, 
>raster, and attribute processing functionality.

I think even this is marginal.  To efficiently do raster analysis the image
file (or database) structure must be of fixed length.  This is the ESRI grid
format.  That way you can directly calculate the values adjacent to the cell
of interest(add or subtract exactly the length of one row from your file
pointer to get the cell above or below).  You cannot do this with a typical
compressed image format.

Bruce