Novice: Contours from GIF

James Cameron cameron at
Thu Sep 18 04:06:28 EDT 1997


I've scanned most carefully a portion of a topographic map, ensuring
that each pixel matches my resolution of five metres.  So my GIF file is
600 x 800 pixels, 3km by 4km.

I've been able to import it using and then adjust it's location
using  Displaying it actually worked too, with d.rast.


1)  how do I make the display show only one portion of the area and
magnify it to show the original level of detail? Or better?

2)  how do I now digitise the GIF to produce a vector map of the
contours?  And a site map of some of the features?

James Cameron                                    (cameron at
Digital Equipment Corporation (Australia) Pty. Ltd. A.C.N. 000 446 800

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