I'm working my way through a paper on Super Resolution, and am having trouble figuring out how to evaluate this equation for the spatial gradient:
The summation limits, wx & wy, are the window size (lets assume wx=2;wy=2)
Ix & Iy are horizontal and vertical gradients of the image. I'm assuming these are actually indexed by (x,y) but don't know that for sure.
The calculation of G should result in a 6x6 matrix for the other equations listed in the paper to make sense.
How do I calculate G?