[GRASSLIST:2306] Re: Question about import of non georeferenced
Eric G. Miller
egm2 at jps.net
Tue Aug 7 21:45:13 EDT 2001
On Tue, Aug 07, 2001 at 10:41:19AM -0700, Rich Shepard wrote:
> On Tue, 7 Aug 2001, Moritz Lennert wrote:
> > You cannot change a region once you defined it. If you want to reproject
> > data into a different projection you will have to create a new location
> > with the desired projection and project from your old location to your new
> > location (r.proj).
> Perhaps I'm particularly dense this morning, but isn't the problem more
> fundamental than this? A scanned image has no region, does it? It's just a
> bunch of bits until it is -- somehow -- georeferenced.
It's "region" (or cellhd) has resolution 1x1 and something like:
north = <cols>
west = 0
south = 0
east = <rows>
Now, say you know what the X-Y resolution should be, and what the
north/south/east/west values should be (but you didn't have a TIFF World
file) -- you can hack the cellhd file directly.
But, if you only know that info in relation to another data set -- check
out i.rectify and related...
Eric G. Miller <egm2 at jps.net>
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