gistfile1.txt

trap "echo q > ctr0; echo q > ctr1; sleep 1; killall -INT ffplay; killall -INT ffmpeg" EXIT
mkfifo prv0 prv1
mkfifo ctr0 ctr1
n0=recordings/$(date +"%m%d%y+%H%M")_r0.mp4
n1=recordings/$(date +"%m%d%y+%H%M")_r1.mp4
n2=recordings/$(date +"%m%d%y+%H%M")_a0.mp4
 
ffplay -i - < prv0 &
 
cat ctr0 | ffmpeg -y -i /dev/video0 -thread_queue_size 512 -i /dev/video1 \
       -filter_complex "[0]split[s0][s1]" \
       -map "[s0]" -f mp4 -vcodec libx264 -preset superfast $n0 \
       -map "1" -f mp4 -vcodec libx264 -preset superfast $n1 \
       -map "[s1]" -pix_fmt yuv422p -f yuv4mpegpipe pipe:3 3>prv0 &
 
cat ctr1 | ffmpeg -y -f alsa -i hw:0 \
          -f alsa -i hw:1 -f alsa -i hw:2 \
          -map 0 -map 1 -map 2 $n2 &
 
wait