Fast Normalized Cross-Correlation

Hi. All,

I'm working on Image processing and using Fast Normalized Cross-
Correlatino method to compare the template image with the Sample
image. Fot the theory I use, I need to undestand two terms.
1) Weighted sum and 2) Rectangulare basis function.

How should I apply this two the template image ? If anyone knows,
reply asap.

Thanks & Regards,
Chauhan P.D