2017/2/27-You can just specify -r 30000/1001 to maintain the average rate (near-abouts). You don't specify which format you're outputting to, but for MP4, ...
2012/8/11-will by default always use a framerate of 30 for output regardless of the framerate of the source file. I know how to set a given framerate e.g. ...
2020/12/1-FFmpeg assigns a default framerate of 25 for inputs which don't have an inherent framerate. What the -r 15 does is drop frames to match the ...
But with this file ffmpeg guesses the wrong frame rate and i convert the file from 24fps to ~29.97fps which lead to stutter movie playback. Audio and Video ...