🚀 go-pugleaf

One of my recent homework assignment is about geometrcal distortion
correction. We model the distortion using second order equations.
That is, the reverse address mapping is:

  u = a0 + a1 * x + a2 * y + a3 * x ^ 2 + a4 * x * y + a5 * y ^ 2;
  v = b0 + b1 * x + b2 * y + b3 * x ^ 2 + b4 * x * y + b5 * y ^ 2;

The idea is actually came from Pratt's "Digital Image Processing", 
page 430. A couple of points are picked and the unknowns a's and 
b's are solved by pseudo inversing the matrix.

However, the a's and b's I obtained are very sensitive to the way
that the reference points are picks. My result, of course, is unsat-
isfactory. I wonder if anybody out there has done similar operation
and could give me some hints or references.

Many thanks.


Patrick Law