[FFmpeg-user] Changing frame rate while not preserving time.

[Vincent Tschanz]

Question about changing framerate without re-encoding (while changing the
duration too).  In theory this is a very simple operation, the frame rate
is just an indication for the player. In practice it's no so simple to do
without re-encoding.

Is there a simpler solution than this two steps command :
'ffmpeg -i 30fps.mp4 -c copy -f h264 30fps.h264'
then
'ffmpeg -r 120 -i 30fps.h264 -c copy 120fps.mp4' ?

Why -r as an input option only works for raw streams?

Thanks