Filter entropy
  Measure video frames entropy.
    Inputs:
       #0: default (video)
    Outputs:
       #0: default (video)
entropy AVOptions:
  mode              <int>        ..FV...... set kind of histogram entropy measurement (from 0 to 1) (default normal)
     normal          0            ..FV......
     diff            1            ..FV......

This filter has support for timeline through the 'enable' option.

