Make a Custom Boot Animation

If this is based on Android it will be REALLY easy to make a custom boot animation, only problem is I dunno what size the pictures need to be..... Is there any chance someone could upload the /system to media fire?
I'm planning on making '' a hand load a handgun, and then load a machine gun'' or the likes since its a gaming platform, and but I can't do anything until I know the size they must be.