Linux Desktop Video Capture

ffmpeg can do this well. It can grab X11 input and create an MPEG at specific fps with the specific resolution:

ffmpeg -f x11grab -s 1280x1024  -r 25 -i :0.0 -sameq /tmp/out.mpg

Here: -s 1280×1024 is the resolution of the screen. Change it to the screen resolution you use.

-r 25 is the FPS rate.