10-Bit High Dynamic Range (HDR) 编辑

With 10-bit High Dynamic Range (HDR) virtual desktop sessions, you can use enhanced encoding and decoding capabilities to render high quality images and videos with an extended range of colors, and greater contrast and brightness. Additionally, you can customize the white luminance level, Extended Display Identification Data (EDID), and visual quality to improve the user experience.

System requirements

Endpoint:

• Citrix Workspace app for Windows 2209 or later
• NVIDIA GPUs with 10-bit HEVC decoding support on the endpoint
• 10-bit HDR supported monitors

Server:

• Windows single-session OS VDA 2209 or later
• NVIDIA GPUs with 10-bit HEVC 444 encoding support on the VDA

Required policies

Endpoint:

• Enable H.265 decoding for graphics

Server:

• Optimize for 3D Graphics workload
• Graphics Status Indicator (optional)

Server configurations

When you launch a Citrix session on a 10-bit HDR enabled endpoint monitor, the HDR session is enabled by default. In multi-monitor HDR sessions, all endpoint monitors must have 10-bit HDR enabled. HDR sessions are supported in both windowed and full-screen modes.

Reference White Level

This setting defines the white luminance level by nit value. It controls the relative HDR screen brightness within the session. The default value is 80 nits. Set the following registry key to define a different nit value:

• HKEY_LOCAL_MACHINE\SOFTWARE\Citrix\Graphics
• Type: REG_DWORD
• Name: RefWhiteLevel

To activate the setting, you must either resize your session, or disconnect and relaunch the session.

EDID Override

You can configure the VDA to use the endpoint monitor EDID for your HDR sessions. This allows you to take full advantage of the monitor’s display capabilities by matching the color gamut and luminance range. By default, HDR sessions assume an HDR1000 capable display. You can export endpoint monitor EDID using NVIDIA or other tools. Apply it to the VDA using the following registry key:

• HKEY_LOCAL_MACHINE\SOFTWARE\Citrix\Graphics
• Type: REG_BINARY
• Name: EDIDOverride

When you store the EDID into the registry, it must not have commas, spaces, or special characters. To activate the override EDID, sign out and launch a new session.

Visual Lossless Experience

Enable the following policies for a visually lossless experience:

• Allow Visual Lossless Compression
• Visual Quality: Always Lossless or Build to Lossless

After the policies are set, you can control the HDR session quality using the Graphics Status Indicator by using the Image Quality Slider, or by switching to pixel-perfect mode.

Other considerations

• On virtual GPUs, you can launch 10-bit HDR sessions on up to four monitors.
• The Citrix session reverts to 8-bit, non-HDR mode in the following instances:
  • If any endpoint monitors do not have 10-bit HDR enabled
  • Enabling screen sharing
  • Setting a virtual display layout on the VDA
  • Switching to pixel-perfect mode without setting the “Allow Visually Lossless Compression” policy