Adding option to enable/disable person segmentation

Just tested this on my iPhone 6S, works great. A couple of suggestions, some of which you probably already have in mind:

the switch could default to disabled on devices that don't support segmentation;
relatedly, on incompatible devices the compatibility alert could be shown as soon as one tries to enable segmentation;
the state of the switch could be remembered across app launches (ditto for the autofocus and audio switches by the way);
if you're only displaying VR content, the foreground camera stream is useless, and overlaying it directly over the background camera stream introduces some artefacts (see image below). I found it better to only display the background stream in that case.

~In the future you may want to offer a richer set of options, e.g. display the real (unsegmented) video image + only the foreground VR camera stream overlaid on top, which I think could give an acceptable result if the user faces the camera…~ (edit: I just realized this last idea was what the background: hidden option did, sorry!)

fabio914 / RealityMixer