Apple TV 4K to gain automatic frame rate & dynamic range switching with tvOS 11.2

31 Oct 2017 | Rasmus Larsen |

Apple’s upcoming tvOS 11.2 software includes support for “automatic mode switching to native frame rate and dynamic range” on Apple TV 4K. But it is not yet true adaptive frame rate switching.

An important step

One of our main criticisms of Apple TV 4K in our review was how it handled SDR/HDR content. We also discussed how it handles frame rates and the issues relating to the implementation.

Apple will start to address these concerns with the upcoming release of tvOS 11.2. The software includes automatic mode switching for both frame rate and dynamic range (SDR/HDR).

- “Starting with tvOS 11.2, Apple TV 4K can automatically switch video display modes to match the native frame rate and dynamic range of video content,” the company said.

The update furthermore restores the Unwatched category for home sharing.

Not yet adaptive frame rate

Apple recommends that app developers ”switch modes only as often as necessary” as it causes many TVs to temporarily black out or flicker. That is why mode switching for both video rate and dynamic range are deactivated by default in tvOS 11.2. The settings can be activated separately on the ‘Video and Audio’ menu as depicted in the pictures above. Apple also discourages developers from using mode switching for short video clips due to these concerns.

Does your tvOS app play video? Learn about the new mode switching options in tvOS 11.2 using AVDisplayManager: https://t.co/P1vzpBeSIV
— Josh Tidsbury (@joshtidsbury) October 30, 2017

True adaptive frame rate is not yet possible with HDMI but Apple may be laying the groundwork with AVDisplayManager and the A10X chip.

The upcoming HDMI 2.1 standard will support adaptive frame rate to ensure that the transmitting device and receiving device always stay in perfect sync in real time. However, it is not yet clear if it can be utilized to bring true adaptive frame rate to media devices like Apple TV 4K. The HDMI organization calls it “Game mode VRR” and has positioned it as a feature for game consoles.

Apple has yet to release tvOS 11.1 that is still in testing. The company did not announce a release date but expect it to take several weeks before tvOS 11.2 is released.

tvOS 11.2 beta features:

tvOS 11.2 includes new features, bug fixes, and security improvements in the OS and SDK, including:
- Automatic mode switching to native frame rate and dynamic range of video content with Apple TV 4K
- Support for switching Apple TV 4K display output to SDR for apps that are GPU-bound when running in HDR
- Restoring Unwatched category in Home Sharing for Movies, TV Shows, and Home Videos