Filter aloop
  Loop audio samples.
    Inputs:
       #0: default (audio)
    Outputs:
       #0: default (audio)
aloop AVOptions:
  loop              <int>        ..F.A.... number of loops (from -1 to INT_MAX) (default 0)
  size              <int64>      ..F.A.... max number of samples to loop (from 0 to INT_MAX) (default 0)
  start             <int64>      ..F.A.... set the loop start sample (from 0 to I64_MAX) (default 0)


