Apple has filed a couple of patent applications with the USPTO; one would allow iPhone users to adjust different elements of a display using a single input. The application, entitled "User Interface Contrast Filter," reveals a technology that examines saturated pixels vs.non-saturated pixels. Since the non-saturated pixels are considered areas of the screen without active content, that area would show the most change...Source: http://www.phonearena.com/news/Apple-files-with-the-USPTO-for-two-new-patents_id46874
