Live camera feed particular color change iOS app

I would like to get a camera live feed functionality done. The task is to open an iOS camera view and in the live view itself it should have capability of converting all the red colors coming in live camera feed into blue color. It should not change the other colors coming in the camera view. Once it has converted all the red parts into blue, it should have a button which can again convert those blue colors into red color. All this should happen in live real time feed of camera. It should work on all the iPhone devices.