Catch keyboard event OF not in front


I’ ve done a videoplayer which is already installed in a few exhibitions. it a simple videoplayer which can tiggered via udp / Tcp or serial signal.

Now i have implemented a keyboard input, they can define a key video pair and start with a keydown the video. OK, this work great on my test machines. but in the museum there a invisble process in front of the openframework app. I tried to use a tool like turbo top to fix the of app in front, but the app couldn’t catch the keydowns.

how can I catch keyboard events, if it is not in the foreground. any ideas.