Filter mestimate
  Generate motion vectors.
    Inputs:
       #0: default (video)
    Outputs:
       #0: default (video)
mestimate AVOptions:
  method            <int>        ..FV..... motion estimation method (from 1 to 9) (default esa)
     esa             1            ..FV..... exhaustive search
     tss             2            ..FV..... three step search
     tdls            3            ..FV..... two dimensional logarithmic search
     ntss            4            ..FV..... new three step search
     fss             5            ..FV..... four step search
     ds              6            ..FV..... diamond search
     hexbs           7            ..FV..... hexagon-based search
     epzs            8            ..FV..... enhanced predictive zonal search
     umh             9            ..FV..... uneven multi-hexagon search
  mb_size           <int>        ..FV..... macroblock size (from 8 to INT_MAX) (default 16)
  search_param      <int>        ..FV..... search parameter (from 4 to INT_MAX) (default 7)


