// Cross Correlation Coefficient

Number CrossCorrelation(Image ImgA, Image ImgB)
{
Number Numerator, Denominator
Numerator=sum((ImgA-mean(ImgA))*(ImgB-mean(ImgB)))
Denominator=sqrt(sum((ImgA-Mean(ImgA))**2)*sum((ImgB-mean(ImgB)) **2))
return Numerator/Denominator
}