Intel Developer Working On Adding HDR Display Support To Wayland / Weston

While the Linux desktop's display stack has largely reached parity with Windows and macOS in recent years (most recently, the DRM core properties hitting Linux 5.0 around Adaptive-Sync / VRR), but one of the areas that has remained elusive has been for full HDR display support. We've seen NVIDIA working on nursing the X.Org-based display stack for HDR while now Intel appears to be working on the necessary Wayland changes.

Back in 2016 is when NVIDIA began looking at the Linux shortcomings for HDR display support and ended up proposing the DeepColor X11 extension (still yet to be merged) and other efforts for an HDR Linux desktop compared to traditional SDR content. Now with Intel's Icelake processors coming out later in the year with "Gen 11" graphics and their Xe discrete graphics potentially coming next year, HDR display support is now on the minds of their open-source driver developers.

Confirmed back at December's Intel Architecture Day is HDR display support for Gen11 (and Adaptive-Sync!) so it's not surprising to find Intel Open-Source Technology Center work on ensuring the Linux desktop will be able to jive with their upcoming hardware.

Shashank Sharma of Intel sent out an initial design proposal today for enabling High Dynamic Range support within Wayland and to get started with the Weston reference compositor. They have a "half-cooked" implementation so far and will begin posting their patches soon, but for now are looking for other Wayland/driver stakeholders to comment on their planned implementation for dealing with HDR video buffers and handling that through with their display hardware.

Wayland compositors will individually (or make use of shared code such as in WLROOTS or so) detect the presence of HDR support in connected displays, tone-map the frame-buffers for the display, handle potential cases like video sub-titles being SDR overlayed onto the HDR content, prepare any necessary color space conversions, pass the HDR information to the kernel, and related work. All the technical details for those interested in the topic can check out this mailing list post for the current Intel Wayland HDR plan that is now up for discussion.