External display HDMI margins

A well-known issue for developers setting a custom UIWindow and its rootViewController on external display with iDevices lightning / HDMI adapter, is that the TV-displayed view doesn't take the whole space when it could.

I know there are some workarounds :

• use an Apple TV : no, for our use the latency makes it irrelevant
• use a VGA cable : no, 1024x768 isn't enough

But there is also a specific case with video players : iOS makes them automatically fitting the full space.

Here is my question : is it feasible to create a video stream capturing my former rootViewController (putting it elsewhere far from the device's screen in the view hierarchy) then reading this stream with the native AV package to achieve my full-screen goal ?

BTW, if you just know another high resolution (1080p) and low latency workaround, that would do it too.

Just setting the external display's UIScreen overscanCompensation to .scale works so there's really no need for any complicated streaming process.