[GRASS-windows] Georectify problems

[Moritz Lennert]

On 26/11/08 16:47, Ken Mycock wrote:
> I'm new to GRASS and am slowly learning my way around.  I've been trying 
> to georectify a raster scan of a historic map to add to a mapset based 
> on modern Ordnance Survey data to compare the topology over the 
> intervening 200 years.  However, whichever way I try I end up with 
> errors and no rectified output.
> 
> Using the georectify tool, I have established seven GCPs and have 
> verified that they are in a POINTS file.  However, whenever I click on 
> either the RMS icon or the rectify icon it throws an error window 
> "WARNING: bad format in control point file for group [Orig_Inc in 
> PERMANENT]  ERROR: Not Enough Points -- 3 are required" (I'm trying 
> first order to begin with).
> 
> Then I tried using i.rectify from the command line in the output window, 
> via Run (GUI), hoping it would use the POINTS file already created.  I 
> successfully completed all the fields in the dialogue, including using 
> the browse function to select the Group, but when I click Run it throws 
> an error in the Output window: "Group Orig_Inc at PERMANENT does not exist."

There was a bug in the group handling which failed on composite names 
(i.e. containing @mapset). Try erasing the @PERMANENT.

Also be aware that i.rectify needs to be run from the source location, 
i.e. the one where your non-georeferenced image lies. This is different 
from the gui georeferencing tool which works from the target location.

You might also have to run i.target in the source location before 
running i.rectify.

This said, if you don't get it to work in the GUI, could you please also 
file a bug report at http://trac.osgeo.org/grass/, so that we are 
reminded to take care of it ?

Thank you,

Moritz