Cutting up video using ffmpeg

Ffmpeg is extremely powerful tool for handing videos.

I just re-note Ben Wong's reply from AskUbuntu.

Summary: ffmpeg -i [input_file] -ss [start_seconds] -t [duration_seconds] [output_file]

Using ffmpeg to cut mp4 video without re-encoding:

ffmpeg -i source.mp4 -ss 00:00:10 -t 00:00:20 -c copy cut_video.mp4

Using ffmpeg to cut mp4 video with re-encoding:

ffmpeg -i source.mp4 -ss 00:00:10 -t 00:00:20 -async 1 -strict -2 cut_video.mp4