YouTube has started rolling out 4K streaming to Apple TV 4K. However, not all users are seeing the 4K option just yet. HDR is not supported and there are limitations.
YouTube 4K on Apple TV 4K
When Apple released tvOS 14 a couple of weeks ago, support for YouTube 4K was missing. The new software laid the groundwork but YouTube had to flip the switch too on its server.
That is happening as we speak. Owners are starting to see the 4K option on Apple TV 4K boxes running tvOS 14.0, tvOS 14.0.1 or tvOS 14.2 beta. Multiple owners on reddit have provided evidence of YouTube 4K working.
However, not everyone is seeing the 4K option just yet, even with tvOS 14 and the latest version of the YouTube app. It appears to be a server-side update from YouTube that is rolling out gradually.
At this time, Apple TV 4K supports YouTube videos in 4K resolution at up to 30fps frame rates. Videos in 50fps or 60fps drop to 1440p resolution.
Another major limitation is that HDR (High Dynamic Range) is not supported at this time. It is not clear if it will be added later or if this is a limitation in Apple's decoding mechanism.
It has been confirmed that Apple TV 4K is using Google's VP9 video codec rather than the new AV1 codec that Apple, Google, Netflix, Microsoft and others have developed in partnership.
YouTube 4K is rolling out but perhaps we will have to wait for new hardware to enjoy the full experience. Apple is rumored to be working on an upgraded version of its Apple TV box that will arrive next year, according to Bloomberg.
- Source: tips, reddit (2)