Filter tlut2
  Compute and apply a lookup table from two successive frames.
    Inputs:
       #0: default (video)
    Outputs:
       #0: default (video)
tlut2 AVOptions:
  c0                <string>     ..FV.... set component #0 expression (default "x")
  c1                <string>     ..FV.... set component #1 expression (default "x")
  c2                <string>     ..FV.... set component #2 expression (default "x")
  c3                <string>     ..FV.... set component #3 expression (default "x")


