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As several points for an image are needed (to get a mean and variance of the detected object), the calculation may become expensive. A projective mapping algorithm is used in hopes of reducing the time needed to get the desired amount of coordinates in an image:
Consider 4 different A vectors
If 3 of them or more are collinear in their plane, grab another set of 4 different A vectors. Repeat until there are no 3 collinear vectors in the set of 4.
Map them down and get their (X,Y) coordinates
Calculate for i, j, and k
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5. Calculate for q, r, s
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6. We calculate the matrix C. This maps any A coordinate to an (X, Y) one.
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With C, any coordinates given from the image can then be transformed into geographic coordinates.