CCOEFF_Denominator by C#

[xtdang93]

First of all I want to say thank you for this meaningful project.
I am rewriting it in c#.
But I am stuck at "CCOEFF_Denominator" function because I don't understand its meaning.
Can you convert it to c# for me?
Thanks a lot.

P/s: I change the method of MatchTemplate to CCoeffNormed. it works without CCOEFF_Denominator function