# ffmpeg -i testfile.wav -c:a libopus -ar 48000 -ac 2 -f opus -map_metadata -1 -vn -y play.opus
# ffmpeg -i testfile.wav \
#    -ac 2 -ar 48000 \
#    -b:a 96k \
#    -f opus \
#    -y \
#    -vbr off \
#    -frame_duration 20 \
#    pipe:1 > output.opus

# Version used by the code sample i found
ffmpeg -i testfile.wav -hide_banner -loglevel quiet -f data -map 0:a -ar 48k -ac 2 -acodec libopus -b:a 128k pipe:1 > testfile.raw

opusinfo output.opus