Filter decimate
  Decimate frames (post field matching filter).
    Inputs:
        dynamic (depending on the options)
    Outputs:
       #0: default (video)
decimate AVOptions:
  cycle             <int>        ..FV..... set the number of frame from which one will be dropped (from 2 to 25) (default 5)
  dupthresh         <double>     ..FV..... set duplicate threshold (from 0 to 100) (default 1.1)
  scthresh          <double>     ..FV..... set scene change threshold (from 0 to 100) (default 15)
  blockx            <int>        ..FV..... set the size of the x-axis blocks used during metric calculations (from 4 to 512) (default 32)
  blocky            <int>        ..FV..... set the size of the y-axis blocks used during metric calculations (from 4 to 512) (default 32)
  ppsrc             <boolean>    ..FV..... mark main input as a pre-processed input and activate clean source input stream (default false)
  chroma            <boolean>    ..FV..... set whether or not chroma is considered in the metric calculations (default true)


