Encoder ac3_fixed [ATSC A/52A (AC-3)]:
    Supported sample formats: s16p
    Supported channel layouts: mono stereo 3.0(back) 3.0 quad(side) quad 4.0 5.0(side) 5.0 2 channels (FC+LFE) 2.1 4 channels (FL+FR+LFE+BC) 3.1 5 channels (FL+FR+LFE+SL+SR) 5 channels (FL+FR+LFE+BL+BR) 4.1 5.1(side) 5.1
Fixed-Point AC-3 Encoder AVOptions:
-per_frame_metadata <int>        E...A. Allow Changing Metadata Per-Frame (from 0 to 1)
-center_mixlev     <float>      E...A. Center Mix Level (from 0 to 1)
-surround_mixlev   <float>      E...A. Surround Mix Level (from 0 to 1)
-mixing_level      <int>        E...A. Mixing Level (from -1 to 111)
-room_type         <int>        E...A. Room Type (from -1 to 2)
   notindicated                 E...A. Not Indicated (default)
   large                        E...A. Large Room
   small                        E...A. Small Room
-copyright         <int>        E...A. Copyright Bit (from -1 to 1)
-dialnorm          <int>        E...A. Dialogue Level (dB) (from -31 to -1)
-dsur_mode         <int>        E...A. Dolby Surround Mode (from -1 to 2)
   notindicated                 E...A. Not Indicated (default)
   on                           E...A. Dolby Surround Encoded
   off                          E...A. Not Dolby Surround Encoded
-original          <int>        E...A. Original Bit Stream (from -1 to 1)
-dmix_mode         <int>        E...A. Preferred Stereo Downmix Mode (from -1 to 2)
   notindicated                 E...A. Not Indicated (default)
   ltrt                         E...A. Lt/Rt Downmix Preferred
   loro                         E...A. Lo/Ro Downmix Preferred
-ltrt_cmixlev      <float>      E...A. Lt/Rt Center Mix Level (from -1 to 2)
-ltrt_surmixlev    <float>      E...A. Lt/Rt Surround Mix Level (from -1 to 2)
-loro_cmixlev      <float>      E...A. Lo/Ro Center Mix Level (from -1 to 2)
-loro_surmixlev    <float>      E...A. Lo/Ro Surround Mix Level (from -1 to 2)
-dsurex_mode       <int>        E...A. Dolby Surround EX Mode (from -1 to 2)
   notindicated                 E...A. Not Indicated (default)
   on                           E...A. Dolby Surround EX Encoded
   off                          E...A. Not Dolby Surround EX Encoded
-dheadphone_mode   <int>        E...A. Dolby Headphone Mode (from -1 to 2)
   notindicated                 E...A. Not Indicated (default)
   on                           E...A. Dolby Headphone Encoded
   off                          E...A. Not Dolby Headphone Encoded
-ad_conv_type      <int>        E...A. A/D Converter Type (from -1 to 1)
   standard                     E...A. Standard (default)
   hdcd                         E...A. HDCD
-stereo_rematrixing <int>        E...A. Stereo Rematrixing (from 0 to 1)
-channel_coupling  <int>        E...A. Channel Coupling (from -1 to 1)
   auto                         E...A. Selected by the Encoder
-cpl_start_band    <int>        E...A. Coupling Start Band (from -1 to 15)
   auto                         E...A. Selected by the Encoder

