The pvsifd opcode takes an input a-rate signal and performs an Instantaneous Frequency, magnitude and phase analysis, using the STFT and pvsifd (Instantaneous Frequency Distribution), as described in Lazzarini et al, "Time-stretching using the Instantaneous Frequency Distribution and Partial Tracking", Proc.of ICMC05, Barcelona. It generates two PV streaming signals, one containing the amplitudes and frequencies (a similar output to pvsanal) and another containing amplitudes and unwrapped phases.
ffr -- output pv stream in AMP_FREQ format
fphs -- output pv stream in AMP_PHASE format
ifftsize -- FFT analysis size, must be power-of-two and integer multiple of the hopsize.
ihopsize -- hopsize in samples
iwintype -- window type (O: Hamming, 1: Hanning)
iscal -- amplitude scaling (defaults to 1).
Example 293. Example
ain inch 1 ; input signal fs1,fsi2 pvsifd ain,2048,512,1 ; pvsifd analysis fst partials fs1,fsi2,.003,1,3,500 ; partial tracking aout resyn fst, 1, 1.5, 500, 1 ; resynthesis (up a 5th) out aout
The example above shows the pvsifd analysis feeding into partial tracking and cubic-phase additive resynthesis with pitch shifting.