set bitrate=3000k
set maxrate=3200k
set bufsize=6000k
set threads=4

ffmpeg -i "INPUT_FILENAME" -c:v libx264 -pass 1 -b:v %bitrate% -maxrate %maxrate% -bufsize %bufsize% -threads %threads% -g 250 -speed 4 -tile-columns 6 -frame-parallel 1 -auto-alt-ref 1 -lag-in-frames 25 -an -sn -f  mp4 -y NUL
ffmpeg -i "INPUT_FILENAME" -c:v libx264 -pass 2 -b:v %bitrate% -maxrate %maxrate% -bufsize %bufsize% -threads %threads% -g 250 -speed 1 -tile-columns 6 -frame-parallel 1 -auto-alt-ref 1 -lag-in-frames 25 -sn -an -f mp4 -y "OUTPUT_FILENAME.mp4"
pause