Filter afftfilt
  Apply arbitrary expressions to samples in frequency domain.
    Inputs:
       #0: default (audio)
    Outputs:
       #0: default (audio)
afftfilt AVOptions:
  real              <string>     ..F.A.... set channels real expressions (default "re")
  imag              <string>     ..F.A.... set channels imaginary expressions (default "im")
  win_size          <int>        ..F.A.... set window size (from 16 to 131072) (default 4096)
  win_func          <int>        ..F.A.... set window function (from 0 to 19) (default hann)
     rect            0            ..F.A.... Rectangular
     bartlett        4            ..F.A.... Bartlett
     hann            1            ..F.A.... Hann
     hanning         1            ..F.A.... Hanning
     hamming         2            ..F.A.... Hamming
     blackman        3            ..F.A.... Blackman
     welch           5            ..F.A.... Welch
     flattop         6            ..F.A.... Flat-top
     bharris         7            ..F.A.... Blackman-Harris
     bnuttall        8            ..F.A.... Blackman-Nuttall
     bhann           11           ..F.A.... Bartlett-Hann
     sine            9            ..F.A.... Sine
     nuttall         10           ..F.A.... Nuttall
     lanczos         12           ..F.A.... Lanczos
     gauss           13           ..F.A.... Gauss
     tukey           14           ..F.A.... Tukey
     dolph           15           ..F.A.... Dolph-Chebyshev
     cauchy          16           ..F.A.... Cauchy
     parzen          17           ..F.A.... Parzen
     poisson         18           ..F.A.... Poisson
     bohman          19           ..F.A.... Bohman
  overlap           <float>      ..F.A.... set window overlap (from 0 to 1) (default 0.75)


