ffmpeg  -i in.mp4 -c:v libx265 -b:v 450k \
-x265-params keyint=1:ref=1:no-open-gop=1:weightp=0:weightb=0:cutree=0:rc-lookahead=0:bframes=0:scenecut=0:b-adapt=0:repeat-headers=1 out.mp4