prefilter: make numSamples configurable
prefilter: make numSamples configurable

e.g. for offline, realtime, lo-spec/hi-spec etc.

zenmumbler/libzm,zenmumbler/stardazed-tx,stardazed/stardazed,stardazed/stardazed-tx,stardazed/stardazed-tx,zenmumbler/libzm,zenmumbler/libzm,stardazed/stardazed-tx,zenmumbler/libzm,stardazed/stardazed,zenmumbler/stardazed-tx,zenmumbler/stardazed-tx,zenmumbler/stardazed-tx