[FFmpeg-user] frame rate change w/o changing frames

[Wayne Poll]

>I have a video from a GoPro Hero8. It was recorded at 29.97 fps. I would like to speed up this video. I figure it would be nice to simply increase the frame rate to 60 fps, so a x2.002 speed-up.
>
>Can this be done without re-encoding the video? I tried:
>ffmpeg -r 60 -i in.mp4 -c:v copy -c:a copy out.mp4 This gave me output that was slightly (1MB, 0.1%) smaller, but the same length in time.

You need to include a filter, like this: - 

-r 60 -vf "setpts=(1/2)*PTS"

Full command would be like this: -

ffmpeg -i in.mp4 -c:v copy -c:a copy -r 60 -vf "setpts=(1/2)*PTS" out.mp4

(I haven't tested this exact CL but I use this type of fame rate change a lot...).

WRP