Filter fade
  Fade in/out input video.
    slice threading supported
    Inputs:
       #0: default (video)
    Outputs:
       #0: default (video)
fade AVOptions:
  type              <int>        ..FV.... 'in' or 'out' for fade-in/fade-out (from 0 to 1) (default in)
  t                 <int>        ..FV.... 'in' or 'out' for fade-in/fade-out (from 0 to 1) (default in)
  start_frame       <int>        ..FV.... Number of the first frame to which to apply the effect. (from 0 to INT_MAX) (default 0)
  s                 <int>        ..FV.... Number of the first frame to which to apply the effect. (from 0 to INT_MAX) (default 0)
  nb_frames         <int>        ..FV.... Number of frames to which the effect should be applied. (from 0 to INT_MAX) (default 25)
  n                 <int>        ..FV.... Number of frames to which the effect should be applied. (from 0 to INT_MAX) (default 25)
  alpha             <boolean>    ..FV.... fade alpha if it is available on the input (default false)
  start_time        <duration>   ..FV.... Number of seconds of the beginning of the effect. (default 0)
  st                <duration>   ..FV.... Number of seconds of the beginning of the effect. (default 0)
  duration          <duration>   ..FV.... Duration of the effect in seconds. (default 0)
  d                 <duration>   ..FV.... Duration of the effect in seconds. (default 0)
  color             <color>      ..FV.... set color (default "black")
  c                 <color>      ..FV.... set color (default "black")


