[CentOS] question on 'VGA in" card

Hi All,

Is there a solution under linux that can accept
video in from another source and show it
but also be able to turn that source off (in an automated way)
and show the normal linux console.
Then (in an automated way) switch back and show the
external source again.

So I want to normally be showing an external VGA input,
then based on some event switch the monitor output to
the normal linux console, then based on another event
switch back to the external VGA signal again.

Thanks,

Jerry