Another possibility is to use the `kamp / krms' value in

  krms rms asig1

to skip some pitch. It is a raw way to measure the harmonicity
of the audio input in your csd. The time-window of `rms' is 1/kr,
~ 0.0003 with sr=44100 and ksmps=16. It is ~ 0.001 (= iupdte)
with ksmps=44.

tito