Need help with selfmade Hough Transform in formula node

Hello everyone,

I'm making my own Face Recognition system and I'm at the phase of making a Hough Transform of my captured CAM-image.

So if a pixel is not zero; I generate its sinusoidal with -90° to 90° and calculate the corresponding value with the general Hough formula. Then for the voting process I increase the value of every pixel by 1.

Now the output is just a bit darker but there is no transformation at all.

I think I interpreted the algorithm wrong or I missed a detail in my coding..

Thanks in advance