Change screen contrast and brightness

I am working on a input manager and I have been searching for how to manipulate the screen brightness and screen contrast through code. Is this possible? I mean I always have the screen resolution, quality, and fullscreen options working perfectly but I need help with brightness and contrast.

Typically those are something that can be set on the monitor and the video card and sometimes even in the video card per application or application content type (video, image, etc.). Unity provides no scripting interface for accessing these settings.

You could access them through a plugin or implement that kind of control through a full-screen image effect shader, both of which requiring Unity Pro.