When giving presentations using a computer that’s not your own, trying to show video clips can end badly. It’s much safer to use animated GIFs instead. Luckily it’s easy to convert videos to animated GIF on the command line using mplayer:
mplayer movie.avi -vo gif89a:output=movie.gif -vf scale=600:337 -ss 4
This command converts “movie.avi” to “movie.gif”, rescales the output to 600:337 and starts at second 4 of the video – skipping the beginning.