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View Full Version : Latest version FFmpeg encoding with x264 changed the fps


zys4416
12th December 2010, 04:42
I updated the FFmpeg to the latest version for linux yestaday and I found a problem

I encoded an mkv file with this script below:

ffmpeg -i input.mkv -an -vcodec libx264 -vpre slower -crf 18 output.mp4

Then I played the output.mp4, and the fps was changed to 24 (Source was 23.976)! Actually, the total number of frames also changed!

e.g:

source frames: 1000s x 23.976fps = 23976
output frames: 1000s x 24fps = 24000

But if I encode as an m2ts file, neither fps nor number of frames was changed (same as the source file).

If anyone could please identify the problem here, I would really appreciate it :)