ffmpeg -i 2022.02.10.mp4 -r 25 ./frames_%04d.png
ffmpeg -f image2 -r 25 -i frames_%04d.png -c:v libx264 -pix_fmt yuv420p out2.mp4
ffmpeg -i test.mp4 -vcodec libx264 -x264opts "bframes=0" -strict -2 test-out.mp4
去掉无效视频帧