iamf_ambisonic_1 124 B

1234
  1. [0:a]channelmap=0:mono[MONO0];
  2. [0:a]channelmap=1:mono[MONO1];
  3. [0:a]channelmap=2:mono[MONO2];
  4. [0:a]channelmap=3:mono[MONO3];