When you plucked on a string, the string is vibrate and except the fundamental frequency, there are an integer multiple of the fundamental frequency, which are the harmonics.
I know that the HPS algorithm is a tool to find the fundamental frequency, but I don't understand the downsample part. How can I know how many times I need to downsample the signal?
I read somewhere that the fundamental frequency can be given by measuring the harmonic frequencies and their GCD (greatest common division)
another source says that there's a need to use the Hanning method. can someone please explain this algorithm?