Filter aemphasis
  Audio emphasis.
    Inputs:
       #0: default (audio)
    Outputs:
       #0: default (audio)
aemphasis AVOptions:
  level_in          <double>     ..F.A.... set input gain (from 0 to 64) (default 1)
  level_out         <double>     ..F.A.... set output gain (from 0 to 64) (default 1)
  mode              <int>        ..F.A.... set filter mode (from 0 to 1) (default reproduction)
     reproduction    0            ..F.A....
     production      1            ..F.A....
  type              <int>        ..F.A.... set filter type (from 0 to 8) (default cd)
     col             0            ..F.A.... Columbia
     emi             1            ..F.A.... EMI
     bsi             2            ..F.A.... BSI (78RPM)
     riaa            3            ..F.A.... RIAA
     cd              4            ..F.A.... Compact Disc (CD)
     50fm            5            ..F.A.... 50µs (FM)
     75fm            6            ..F.A.... 75µs (FM)
     50kf            7            ..F.A.... 50µs (FM-KF)
     75kf            8            ..F.A.... 75µs (FM-KF)


