ffmpeg.exe -i input -sn -c:v libvpx-vp9 -y -b:v 0 -qmin 10 -qmax 42 -crf 24 -threads 4 -frame-parallel 0 tile-columns 2 -strict -2 -rc_lookahead 25 -lag-in-frames 16 -g 480 -sc_threshold 40 -auto-alt-ref 1 -arnr_strength 3 -arnr_max_frames 8 -arnr-type centered -c:a libopus -b:a 64K -vf scale=-1:720 -pix_fmt yuv420p  -speed 4 -pass 1 -ss 00 -to 99 -f webm NUL

ffmpeg.exe -i input -sn -c:v libvpx-vp9 -y -b:v 0 -qmin 10 -qmax 42 -crf 24 -threads 4 -frame-parallel 0 tile-columns 2 -strict -2 -rc_lookahead 25 -lag-in-frames 16 -g 480 -sc_threshold 40 -auto-alt-ref 1 -arnr_strength 3 -arnr_max_frames 8 -arnr-type centered -c:a libopus -b:a 64K -vf scale=-1:720 -pix_fmt yuv420p  -speed 1 -pass 2 -ss 00 -to 99 -f webm output.webm