i.rectify2

Malcolm Williamson malcolm at cast.uark.edu
Wed Jan 5 15:44:26 EST 1994


(older stuff deleted)
> 
> Your supposition is right on the mark. i.rectify2 only applies a best
> fit second order polynomial transformation to the source image,
> whereas the ll to lcc transformation, over the area of interest, is
> most likely much more complex.  The problem can be solved using
> your PROJ routines to calculate the exact tranformation details
> for each pixel in the source image. In practice, one should define an
> image in the target coordinate system and calculate the inverse
> transformation to ll to find pixel values. A lot of calculations,
> but what are computers for.
> 
> Bob Courtney
> Atlantic Geoscience Centre
> 

I just found an old posting from the list that should apply to this:

-----Included Message-------

Yes I have a program called r.proj which will work like v.proj, however,
I donot have a clean man page for it. Further, it needs mapgen properly
installed (v.proj also requires mapgen). Once you ran the r.proj, I have
another program called r.neigh a modified version of r.neighbor which fills
any holes that was not filled while running r.proj either using mode or average
method depeneding on the type of layer. This version of r.neigh modifies only
those cells that are null data or no data.

I will put both the programs in anonymous ftp site
brcsun1.tamu.edu
under pub/outgoing/srin
called r.proj.tar and r.neigh.tar

Any comments to improve them are welcome and can be directed to srin at iiml.tamu.e
du

Thanks.

Srinivasan
srin at iiml.tamu.edu

------End Included Message------


By the way, I just tried the ftp site and was not granted guest privileges.
Guess you'll need to contact Srinivasan.

-- 
Malcolm D. Williamson - Research Assistant       E-mail: malcolm at cast.uark.edu
Center for Advanced Spatial Technologies      Telephone: (501) 575-6159
Ozark Rm. 12                                        Fax: (501) 575-3846 
University of Arkansas              
Fayetteville, AR 72701



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