--http-mux mp4 --http-audio-codec libfdk_aac --http-audio-bitrate 128
Note the use here of the MP4 mux and AAC audio. “libfdk_aac” signals
-te use of Franhofer's `FDK-AAC <https://github.com/mstorsjo/fdk-aac>`_ encoder
+the use of Franhofer's `FDK-AAC <https://github.com/mstorsjo/fdk-aac>`_ encoder
from Android; it yields significantly better sound quality than e.g. FAAC,
and it is open source, but under a somewhat cumbersome license. For this
reason, most distributions do not compile FFmpeg with the FDK-AAC codec,