simultaneous stream on std with audio being transcoded into a file

[pavan_savoy]

I've been able to transcode audio into a wav from the mp3 while playing a mp4 file, However the video stream doesn't get played on the UI and gets lost.
vlc -vvv video1.mp4 --sout "#transcode{acodec=mp3}:std{access=file,mux=wav,dst=o.wav}"
what command line options do I give to simultaneous play the video on the UI, but keep transcoding the audio from mp3 into a wav file?

[Jean-Baptiste Kempf]

duplicate{dst=display,dst=std... }