HDR Calibration Sample

This HDR Calibration Sample project shows how an HDR calibration menu with Neutral Tonemapping can be implemented.

Requirement:

• Unity 2022.3.13f1 or above
• Universal Render Pipeline (URP) or High Definition Render Pipeline (HDRP)

Getting the project

1. Clone this repository OR click here to download project zip
2. Open project with Unity Editor (please use the version listed in the above Requirement section)

How to use

1. Open “HDRCalibrationSample” scene
2. Hit play
3. Control - you can either use mouse or keyboard or game controller to interact with the UI

Function	Mouse / Touch	Keyboard	Game Controller
Menu Item Select	Click on-screen buttons	Arrow keys	D-Pad Up/Down
Confirm	Click on-screen buttons	Enter	South Button
Back	Click on-screen buttons	Esc / Backspace	East Button
Show/Hide UI	Click on-screen buttons	Tab	North Button
Display Info	Click on-screen buttons	Shift	West Button
Switch Sample Images	Click on-screen buttons Swipe left/right	PageUp / PageDown	Left/Right Trigger Left/Right Shoulder

Default Tonemapping values

• If HDR is available on the current display, the default values will be using the HDROutputSettings API paperWhiteNits, minToneMapLuminance and maxToneMapLuminance values.
• If HDR is not available or the HDROutputSettings API couldn’t detect the luminance values, the default will be a set of hard-coded values.

Sample images

The HDR Calibration Sample comes with a few .EXR images captured from the HDRP template project. The images showcase some outdoor (bright) and indoor (dark) environments. When you are implementing your own calibration scenes, you should use the brightest and darkest environments in your project.
These images are useful for users to adjust the brightness values to make the bright part not overexposed, dark part not completely invisible, and the UI is still clear to read.

Display info

The popup prints the important information using the HDROutputSettings API.
Note that the luminance values might change according to screen brightness, and is only effective on player start (i.e. if you change screen brightness while player is running, you will have to restart the player to refresh the value).
For more information about HDROutputSettings API, visit documentation.

Error popup

If GameView or player is not running in HDR, the popup will appear and indicate possible reasons of why HDR is not available.

Fullscreen min/max calibration

The full-screen calibration allows users to calibrate the tonemapping values with max/min brightness. It has 3 pages:

1. The background has maximum brightness. The Unity logo brightness value determines the tonemapping max nits.
2. The background is completely dark (0 brightness). The Unity logo brightness value determines the tonemapping min nits.
3. Half of the background is in max brightness and half in 0 brightness. This page allows users to adjust a suitable paper white value for shader value 1 elements like UI. This is expected that while adjusting the brightness on this page, both the background and logo / UI brightness will be affected.

Camera stacking

The “HDRCalibrationSample" also showcases the setup for camera stacking. In order for HDR rendering to work, all cameras need to be in the same color space. Therefore, make sure Tonemapping is only applied on the last camera on the camera stack.

In the “HDRCalibrationSample scene, there is:

• Main Camera
  • It is rendering 3D objects and only taking Volume_MainCamera for Post-processing which is on layer “Default”.
  • On the VolumeProfile_MainCamera, you can apply any post-processing effects besides Tonemapping.
• UI Camera
  • It is rendering UI Canvas on UI layer, only takes Volume_Tonemapping for Post-processing, which is on layer “Tonemapping”.
  • On the VolumeProfile_Tonemapping, Tonemapping must be only applied here as this VolumeProfile is being used on the last camera of the camera stack. You can apply further post-processing effects as well.

SpectrumTestScene

Open the “SpectrumTestScene” scene and this scene is useful for testing the colors on the display.