[FFmpeg-user] Sharing an audio encode among two outputs

[PSPunch]

Hi,

I have the following working command.

It takes a set of video/audio as input and outputs the transcoded result  
in two formats. Among the two, only the video resolution&datarate  
differ. Audio format&rate is the same.

All is working fine. However, it seems there is redundancy in the audio  
encoder doing the same job for both outputs.

Is there a way to brush this up, do the audio encode just once?
A solution in a single process would be ideal. As CPU load is low  
anyway, I would prefer to keep this in a single instance if piping is  
the only solution.


ffmpeg \
  -fifo_size 1500000 \
   -i udp://127.0.0.1:1234 \
    -filter_complex "[0:v]yadif=0:-1:0,split=2[out1][out2]" \
    -map "[out1]" -map 0:a \
     -vsync passthrough \
     -vcodec h264_nvenc -b:v 2M \
     -acodec aac -b:a 64k \
     -f flv rtmp://192.168.1.63/live/hd \
    -map "[out2]" -map 0:a \
     -vsync passthrough \
     -s 720x576 \
     -vcodec libx264 -crf 30 \
     -acodec aac -b:a 64k \
     -f flv rtmp://192.168.1.63/live/sd


Thank you.
-- 
David Shimamoto