Say no more to big video files stored on disk only for few seconds of content.

You can also make short clips for sharing on YT/Vimeo etc.

Just install ffmpeg on Ubuntu/Debian

sudo apt-get install ffmpeg

then set start and end of a clip

ffmpeg -i longvideo.avi -vcodec copy -acodec copy -ss 00:34:00 -t 00:40:00 shortvideo.avi

Voilà!

It’s not transcoded so it’s fast and new file have original quality.

Source http://askubuntu.com/a/56044/453981