The latest version of Android TV – version 7.0 – has system level support for all three major HDR formats; Dolby Vision, HDR10, and HLG (Hybrid Log-Gamma). This could help bring HDR to more video apps and TVs.
Better HDR support in Android
Something struck us the other day. There are no Android TVs with Dolby Vision support and the first Android TV that was supposed to come with Dolby Vision, TCL’s X1 model, was strangely launched at IFA without even a word about Dolby’s HDR format (it was one of the highlights for TCL X1 at CES).
So we contacted TCL and asked them to clarify. They did not really clarify at this point but we received a quite curious answer that may suggest that Dolby Vision is not yet ruled out. To be clear; to support Dolby Vision a TV needs a dedicated hardware chip. No chip, no support. However, some manufacturers - such as Loewe - have launched TVs without Dolby Vision enabled at launch. The chip is already built in and a later firmware update will enable it.
Our point is that to support Dolby Vision on a system level any Android TV would have to run Android version 7.0. None of them do at the moment. In fact, only very few of them even run Android 6.0 today, about one year after release. We do not mean to suggest that for example Sony Z9D will get updated to support Dolby Vision (we do not think it will), which was rumored before launch, but TCL’s X1 might. Or not. For what it is worth, TCL is still listed as a partner on the official Dolby Vision webpage with an active link pointing to the TCL X1.
How Google will support HDR
In Google’s Android TV 7.0 documentation the section on how to implement HDR reads:
- “In Android 7.0, initial HDR support has been added, which includes the creation of proper constants for the discovery and setup of HDR video pipelines. That means defining codec types and display modes and specifying how HDR data must be passed to MediaCodec and supplied to HDR decoders. HDR is only supported in tunneled video playback mode.”
We take the last sentence to mean that HDR is only supported for video in Android at the moment. Google is laying the foundation. HDR support will probably be added to apps in general and games later on.
Anyways, it is great to see Google support all three major HDR formats. It will help turn Android TV into the universal TV platform that Google imagined. And by supporting several different formats on a system level, Google can offer TV manufacturers some degrees of freedom even though they all get offered the same flavor of the Android TV operating system.
The table above outlines how Google will support HDR in Android 7.0. As you can see, Dolby Vision and HDR10 will use the ST.2084 – or PQ – transfer function and HEVC compression. For the HLG (Hybrid Log-Gamma) HDR format, Google hopes to utilize its in-house VP9 compression format. HDR video in HLG can also be compressed using HEVC.
Now we just need TV manufacturers to adopt Android TV 7.0. Maybe next year.