Un lien qui explique simplement plein de choses concernant la gestion des pixels quant on est en mode console sous linux.
Par exemple, même si on installe pas X, on peut tout de même visualiser des images par l'intermédiaire de la commande fbi.


Le lien :
http://hacklab.cz/2012/04/22/usefulness-linux-framebuffer-virtual-console


Et tant qu'on y est un lien sur comment qu'on dump du random dans un device audio :
http://unix.stackexchange.com/questions/13732/generating-random-noise-for-fun-in-dev-snd


Et plus particulièrement le passage :

I think the reason this isn't working for you is because that interface has been deprecated. You normally can't write audio using /dev/dsp anymore, at least without being tricky. There is a program that will accomplish this for you on your system: padsp. This will map the /dev/audio or /dev/dsp file to the new Audio Server system. Fire up the terminal and get into root mode with sudo su. Then, I'm going to cat /dev/urandom and pipe the output into padsp and use the tee command to send the data to /dev/audio. You'll get a ton of garbage in your terminal, so you may want to redirect to /dev/null. Once you're in superuser, try this command: cat /dev/urandom | padsp tee /dev/audio > /dev/null You may even want to try with other devices, like your mouse: Use: /dev/psaux, for instance or the usb driver. You can even run your memory through it: /dev/mem1 Hope this clarifies why it wasn't working before. Personally, I found the mouse and memory to be way more interesting than playing random static!