Hi,
I'm building a tvOS client that uses the native Apple player (AVPlayer/AVFoundation) rather than a bundled software decoder. On Apple TV that's the only path that gets you hardware decoding, Match Dynamic Range and Match Frame Rate — but it also means I'm bound by what AVFoundation accepts, and that's where I've run into a wall.
What I observe
My device profile advertises HLS transcoding with an MP4 container:
{
"Type": "Video",
"Protocol": "hls",
"Container": "mp4",