[GRASSLIST:3239] Digitizing point data from raster image
ihatejunkyabastards at yahoo.com
Tue Feb 26 23:47:13 EST 2002
I've just done some digitizing of spot heights off of a raster map, and
was wondering if there was a better way to go about this..
After r.in.tiff, i.group, i.target, i.point, and i.rectify to get my
scanned-in map registered correctly, I tried using v.digit with 'Backdrop
CELL Map' turned on.
It worked, but the process of digitizing a couple of points, quiting to
the label menu, entering a new category and unique attribute label, then
selecting the relevant point on the map, then zoom to a new section, and
repeat, is tremendously inefficient when you are trying to put in several
Being able to click on a point, then be prompted for a label, <enter>
repeat, with category numbers auto-incrementing in the background would be
Which led me to do it the way I did it:
Use i.points to select positions, enter the spot height and a zero when
prompted for an easting and northing, and repeat. After that's all done,
save the resulting table to a file, edit the file to remove the uneeded
columns and header, and s.in.ascii the results.
Worked quite well, but it seems a tad bit round-about.
Did I miss the 'correct' way of doing this ?
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