Filter weave
  Weave input video fields into frames.
    Inputs:
       #0: default (video)
    Outputs:
       #0: default (video)
weave AVOptions:
  first_field       <int>        ..FV..... set first field (from 0 to 1) (default top)
     top             0            ..FV..... set top field first
     t               0            ..FV..... set top field first
     bottom          1            ..FV..... set bottom field first
     b               1            ..FV..... set bottom field first


