Filter aphasemeter
  Convert input audio to phase meter video output.
    Inputs:
       #0: default (audio)
    Outputs:
        dynamic (depending on the options)
aphasemeter AVOptions:
  rate              <video_rate> ..FV...... set video rate (default "25")
  r                 <video_rate> ..FV...... set video rate (default "25")
  size              <image_size> ..FV...... set video size (default "800x400")
  s                 <image_size> ..FV...... set video size (default "800x400")
  rc                <int>        ..FV...... set red contrast (from 0 to 255) (default 2)
  gc                <int>        ..FV...... set green contrast (from 0 to 255) (default 7)
  bc                <int>        ..FV...... set blue contrast (from 0 to 255) (default 1)
  mpc               <string>     ..FV...... set median phase color (default "none")
  video             <boolean>    ..FV...... set video output (default true)
  phasing           <boolean>    ..FV...... set mono and out-of-phase detection output (default false)
  tolerance         <float>      ..FV...... set phase tolerance for mono detection (from 0 to 1) (default 0)
  t                 <float>      ..FV...... set phase tolerance for mono detection (from 0 to 1) (default 0)
  angle             <float>      ..FV...... set angle threshold for out-of-phase detection (from 90 to 180) (default 170)
  a                 <float>      ..FV...... set angle threshold for out-of-phase detection (from 90 to 180) (default 170)
  duration          <duration>   ..FV...... set minimum mono or out-of-phase duration in seconds (default 2)
  d                 <duration>   ..FV...... set minimum mono or out-of-phase duration in seconds (default 2)


