The new Apple TV supports QMS VRR (Quick Media Switching, Variable Refresh Rate) so that when switching from one framerate to another (like 24 to 60Hz) there isn’t a screen blackout.
However, changing resolution or dynamic ranges, still result in blackouts. But why?
I’m thinking this is an HDMI limitation/issue, but why is this not a problem for iPhones or built in apps?
My initial thought is because with iPhone, Apple makes both the hardware and software, this the integration is better.
With Apple TV and a television, Apple can’t control how every brand/model of television will respond.
TVs cant instantly switch because of the syncing of audio and video, all video signals are heavily processed in all modern TVs, Audio is generally decoded. to Match this delay of recording vs processing TVs need a few ms to buffer process and sync. This will always be the case using HDMI as the standard offers no advance warning just a new data rate / resolution.