Enable Neural Frame Rate Upscaling in Unreal Engine
Introduction
Understand neural graphics and NFRU
Set up the development environment
Set up the Unreal project with NFRU enabled
Validate NFRU in Unreal Engine
Understand console variables for NFRU
Set up a debug view in Unreal Engine
Use RenderDoc for Arm GPUs with NFRU for debugging and analysis
Next Steps

  Log an issue

  Fork and edit

  Discuss on Discord

Understand where NFRU runs

NFRU does not run in the Unreal Editor viewport or Play In Editor (PIE). Test it in Standalone Game or a packaged Windows game. Select Standalone Game from the Editor’s Play menu to launch a separate game process.

Test in Standalone Game

  1. Open the project in Unreal Editor.
  2. Open the Play options menu and select Standalone Game.
  3. In the Standalone Game window, open the console and use the NFRU verification commands.

Test in a packaged Windows game

  1. In Edit > Project Settings > Packaging, select the Development build configuration so the game console is available.
  2. In the Editor toolbar, select Platforms > Windows > Package Project and choose an output directory. Wait for packaging to complete.
  3. Run the game executable from the packaged output directory, then open its console and use the NFRU verification commands.

Packaging builds the game and cooks its content for Windows. Use Standalone Game for quick checks. Use a packaged build to validate the output you’ll distribute.

Verify NFRU in Standalone Game or a packaged build

Open the console in the running game and enter:

    

        
        
r.NFRU.Enable 1
r.NFRU.ShowDebugView 1
stat FrameGen

r.NFRU.ShowDebugView 1 displays the NFRU intermediate-buffer grid. If the grid updates during gameplay, NFRU is generating frames. Use stat FrameGen to check frame generation and presentation pacing.

Image Alt Text:NFRU debug output displayed in a running Windows gameUse the debug view to verify NFRU in Standalone Game or a packaged build

Enter r.NFRU.ShowDebugView 0 when you want to disable the debug grid.

Know when to rebuild or package again

Standalone Game uses the current project. Relaunch it after changing settings or content. Package the game again after changing code, settings, shaders, or assets.

Troubleshooting

NFRU does not start

Select Standalone Game from the Editor’s Play menu or launch the packaged game executable. Selected Viewport and New Editor Window (PIE) do not run NFRU.

Also confirm that:

  • Arm Neural Graphics Plugin is enabled.
  • Vulkan is the project’s default RHI.
  • Vulkan Configurator is running with the Graph layer before the Tensor layer.
  • The active Vulkan implementation exposes VK_ARM_data_graph_optical_flow.

The game crashes after NFRU is enabled

A crash after enabling NFRU can indicate a missing or incorrectly ordered Vulkan emulation layer.

Image Alt Text:Crash dialog after enabling NFRUCheck the Vulkan emulation configuration if the NFRU build crashes

In Vulkan Configurator, check that the layer path points to the plugin’s Binaries\ThirdParty\VulkanMLEmulation\Win64 directory. Enable both layers, place Graph before Tensor, and restart the game.

You have now run NFRU in Standalone Game or a packaged Windows build and verified it with the debug view and frame-generation statistics. Next, use the project settings and console variables to tune NFRU.

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