What algorithm is used for AudioLocalMeasurements: FundamentalFrequency?

I want to determine the “pitch”-tracks for a number of monophonic audio files. Does anyone know what algorithm is used for

AudioLocalMeasurements[a, "FundamentalFrequency"]

?

Hi. I asked the developers in charge of this. I’m not personally familiar with this, but it’s apparently a variation on the YIN algorithm:

Thanks, is there more information about the tuning parameters?