[GRASSLIST:1494] Re: Importing rasters without coordinate system

[Markus Neteler]

On Fri, Oct 10, 2003 at 03:43:41PM +0200, Kris Nackaerts wrote:
> Dear,
> 
> I'm new to GRASS and experimenting. I have a location specified and want 
> to import some rasterdata (aerial imagery) that is not referenced yet. I 
> have this data in A/I ASCII GRID format. When I try to import it, I 
> loose evrything, since it's ll corner coordinates as defined in the 
> header are outside the LOCATION - region. Do I specify a dummy location 
> and import all files here before registring the images, or is there a 
> more elegant solution?

The problem is that unreferenced data are imported with
negative coordinates by r.in.gdal. So try

#-e extends the default location:
r.in.gdal -e in=aaigrid out=yourrastermap

g.region -p rast=yourrastermap
d.mon x0
d.rast yourrastermap

Then you can use i.group, i.target, i.points, i.rectify or
i.ortho.photo to get a referenced/orthorectified aerial image.

Hope this helps,

 Markus