Filter hilbert
  Generate a Hilbert transform FIR coefficients.
    Inputs:
        none (source filter)
    Outputs:
       #0: default (audio)
hilbert AVOptions:
  sample_rate       <int>        ..F.A...... set sample rate (from 1 to INT_MAX) (default 44100)
  r                 <int>        ..F.A...... set sample rate (from 1 to INT_MAX) (default 44100)
  taps              <int>        ..F.A...... set number of taps (from 11 to 65535) (default 22051)
  t                 <int>        ..F.A...... set number of taps (from 11 to 65535) (default 22051)
  nb_samples        <int>        ..F.A...... set the number of samples per requested frame (from 1 to INT_MAX) (default 1024)
  n                 <int>        ..F.A...... set the number of samples per requested frame (from 1 to INT_MAX) (default 1024)
  win_func          <int>        ..F.A...... set window function (from 0 to 19) (default blackman)
     rect            0            ..F.A...... Rectangular
     bartlett        4            ..F.A...... Bartlett
     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
  w                 <int>        ..F.A...... set window function (from 0 to 19) (default blackman)
     rect            0            ..F.A...... Rectangular
     bartlett        4            ..F.A...... Bartlett
     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


