ffmpeg.sh

# webm - mp4
ffmpeg -hide_banner \
    -re -f lavfi -i "testsrc2=size=1280x720:rate=30,format=yuv420p" \
    -f lavfi -i "sine=frequency=220:beep_factor=4:duration=5" \
    -c:v libx264 -preset ultrafast -tune zerolatency -profile:v high \
    -b:v 1400k -bufsize 2800k -x264opts keyint=30:min-keyint=30:scenecut=-1 \
    -c:a aac -b:a 128k \
    -window_size 5  -extra_window_size 10 -remove_at_exit 1 -adaptation_sets "id=0,streams=v id=1,streams=a" \
    -fflags +genpts \
    -movflags isml+frag_keyframe output.mpd
    
# webm - vp9 
ffmpeg -hide_banner \
    -re -f lavfi -i "testsrc2=size=384x216:rate=30,format=yuv420p" \
    -f lavfi -i "sine=frequency=220:beep_factor=4:duration=5" \
    -map 0 -c:v libvpx-vp9 -deadline realtime \
    -minrate 400k -maxrate 400k -b:v 400k -keyint_min 30 -g 30 \
    -map 0 -c:v libvpx-vp9 -deadline realtime -s 254x144 \
    -minrate 400k -maxrate 400k -b:v 400k -keyint_min 30 -g 30 \
    -map 1 -c:a libvorbis -b:a 128k \
    -window_size 5  -extra_window_size 10 -remove_at_exit 1 -adaptation_sets "id=0,streams=0,1 id=1,streams=a" \
    -fflags +genpts \
    -movflags isml+frag_keyframe output.mpd