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

[Carl Eugen Hoyos]

Am Mi., 8. Jan. 2020 um 21:32 Uhr schrieb Green Koopa <greenkoopa at gmail.com>:
>
> 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.

It should work if you extract the video first:
$ ffmpeg -i in.mp4 -c copy -f rawvideo out
$ ffmpeg -r 60 -i out -c copy out.mp4
(You may need an mkv file as additional intermediate)

I don't understand why you are also trying to copy audio,
this will most likely not work...

Carl Eugen