Filter astreamselect
  Select audio streams
    Inputs:
        dynamic (depending on the options)
    Outputs:
        dynamic (depending on the options)
astreamselect AVOptions:
  inputs            <int>        ..FVA... number of input streams (from 2 to INT_MAX) (default 2)
  map               <string>     ..FVA... input indexes to remap to outputs


