I am looking for detailed docs of the results of these two functions and the differences between these two functions. Where can I find them?
are you aware of this site?
based on this, what trouble did you encounter finding the specific docs of those APIs?
I found this: OpenCV: Structural Analysis and Shape Descriptors and than Image moment - Wikipedia for HuMoments but nothing for Moments OpenCV: Structural Analysis and Shape Descriptors.
Edit: Just found: OpenCV: cv::Moments Class Reference.