AudioGraphSpectral Windowed FFT tap: spectral_flatness / peak_ratio / peak_freq / hum_energy (the tone / static-noise / mains-hum substrate). window_ms becomes the FFT size at the stream’s rate. Field Type Repeated Description input uint32 window_ms double Member of Message Description AudioGraphNode One node in the graph. (Extended one op at a time.) AudioGraphSilenceDetect AudioGraphSpectrum