A command that creates a Spectrogram object from the selected Sound and Pitch objects by band filtering in the frequency domain with a bank of filters whose bandwidths depend on the local pitch.
The filter functions used are:
|H(f, F0) = 1 / (((fc2 - f2) /f·B(F0)))2 + 1),|
where fc is the central (resonance) frequency of the filter. B(F0) is the bandwidth in Hz and determined as
|B(F0) = relativeBandwidth·F0,|
where F0 is the fundamental frequency as determined from the Pitch object. Whenever the value of F0 is undefined, a value of 100 Hz is taken.
© djmw, October 24, 2014