fmpeg -i inputfile.mp4 -vf "transpose=1" outputfile.mp4
0=90CounterCLockwise and Vertical Flip (default)
1=90Clockwise
2=90CounterClockwise
3=90Clockwise and Vertical Flip
旋轉180度可用 transpose=2,transpose=2
去掉metadata 中的rotate 屬性
-metadata:s:v:0 rotate=0