🚀 go-pugleaf

If all you want to do is rotate the image such that you get a straight-down
view of it, a simple geometric transformation with some kind of
bilinear interpolation will do what you want -- a little guesswork about
slant angles is all that's needed.  Try looking in an elementary image
processing book.  I don't know of any commercial software that'll
do this, but it's easily within the processing power of a Mac, if
you don't mind waiting a few tens of minutes per transformation.

Getting elevation data from a single image can also be done, given
a knowledge of lighting angle and surface reflectivity characteristics;
it's like doing image synthesis backwards, and the process is usually
called photoclinometry.  Such techniques have been used on data from
the Voyager mission since stereo pairs typically weren't available.

I'm a little bemused by peoples' reactions to this problem; it just isn't
as hard as y'all thought...

	Mike Caplinger, mike@bellcore.com