Decoder aac [AAC (Advanced Audio Coding)]:
    Supported sample formats: fltp
    Supported channel layouts: mono stereo 3.0 4.0 5.0 5.1 7.1(wide)
AAC decoder AVOptions:
  -dual_mono_mode    <int>        .D..A. Select the channel to decode for dual mono (from -1 to 2)
     auto                         .D..A. autoselection
     main                         .D..A. Select Main/Left channel
     sub                          .D..A. Select Sub/Right channel
     both                         .D..A. Select both channels

