From grass-lists-owner@max.cecer.army.mil Tue May 11 21:48:22 1993
Date: Tue, 11 May 1993 19:23:20 -0700
From: alicia@deepthought.ucdavis.edu (Alicia Palacios)
Sender: lists-owner@max.cecer.army.mil
Reply-To: grassu-list@max.cecer.army.mil
To: info-grass-user@ux1.cso.uiuc.edu
Subject: georeferencing
Content-Length: 439I have a raster file and a vector file from a scanner, they are in
x,y coordinates.What is the way to import this files in grass in a mapset
already georeferenced to UTM?
It is possible to georeference to utm coordinates inside of grass,
or it is necessary to import the files with the correct coordinates?
Also, is it possible to import a dxf raster or it should be a vector?
Thanks for your help.
Alicia.
alicia@deepthought.ucdavis.edu
To bring a scanned raster or vetor file into GRASS to georeference it, you
should create a X-Y GRASS LOCATION first, then load your ungeoreferenced
data into this LOCATION. After this new LOCATION is created, use i.target to
link this ungeoreferenced LOCATION to an existing georeferenced LOCATION (UTM,
etc.), followed by i.points to interactively select ground control points on
the scree and build transformation matrix. The last step is to use i.rectify
actually georeferencing the scanned image (raster file).
Wang Song
wang@cast.uark.edu