Color LUT Tweaks

Small Windows CLI for loading raw .lut gamma ramps and applying them when HDR or SDR is active. With this application, you can load separate .lut files everytime you switch to HDR or SDR mode.

Features

• Load .lut files for SDR and HDR;
• Automatically configure Windows color settings (Color Profiles, ACM, etc)

Roadmap

MVP

• Loading LUT files in SDR and HDR.
• Support for configuration presets.
• Preset for Xiaomi G Pro 27i.
• Automatic Windows configuration of ICC / ICM profiles and Auto Color Management.
• Automatic NVIDIA configuration of system color settings.
• Automatic monitor configuration using DDC/CI.
• Improve initial loading performance for faster auto start.

Future

• Automatic AMD configuration of system color settings.
• Automatic Intel Graphics configuration of system color settings.
• Create graphical user interface.
• Improve command line interface.
• MacOS support.
• Linux support.

Installing

Download the latest release, or download the source code of this project and build it using cargo:

cargo build --release

This will build the project in target/release, where it's ready to be executed. Important files:

• luts/: optional pre-built LUTs folder; it's recommended to copy this folder to the same folder as the executable if you decide to move the executable somewhere else.
• configs/: pre-built configurations files (shown in "Presets" menu);
• profiles/: bundled ICC/ICM color profiles;
• color-lut-tweaks.exe: the main executable;

Running

After having your project build and configuration in place, run the executable. It will start running in the background and will appear in the system tray.

color-lut-tweaks.exe

Configuration

The configuration file is a JSON array of LUTs to load.

The following example shows a configuration that loads the identity LUT when you are in SDR (i.e. no color correction) and a custom LUT when you are in HDR:

[
  {
    "device": [0, "XMI27B2", "Mi Monitor"],
    "mode": ["sdr"],
    "lut": "identity"
  },
  {
    "device": 0,
    "mode": "hdr",
    "lut": "./path-to-my-lut.lut",
    "adjust": {
      "contrast": 1.00,
      "brightness": 0.0,
      "gamma": 1.0,
      "gain": [1.0, 1.0, 1.0],
      "offset": [0.0, 0.0, 0.0]
    },
    "windows": {
      "autoColorManagement": false,
      "sdrColorProfile": null,
      "hdrColorProfile": "Xiaomi G Pro 27i HDR DisplayCal.icm"
    }
  }
]

device can be a single number/string or an array interpreted as "any of". Numbers match the active device index. Strings first try the monitor hardware id, such as XMI27B2, then the readable monitor name, such as Mi Monitor.

mode can be "hdr", "sdr", or an array interpreted as "any of".

Windows profile values can be omitted to do nothing, set to null to clear the current-user association for that display mode, or set to an .icm/.icc path. Bare profile names are loaded from the bundled profiles/ folder.

Xiaomi G Pro 27i Users

This project also includes a default Xiaomi G Pro 27i HDR EOTF curve correction (because this is what motivated me to create this tool) and Native to sRGB lut. You can use it by simply starting the application and selecting the desired preset. If the monitor device id is not 0, click on the "Edit" button and manually edit the device number.

Check the Xiaomi G Pro 27i Guide docs for more details.

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Contributing

Requirements

Required tools for development:

• cargo: Required to build and run the project in development mode.
• prek: Used for development quality checks.

Development Commands

Useful commands for development:

• cargo build: Build the project.
• cargo run: Run the project in system tray mode.
• cargo run -- <args>: Run the project in CLI mode.
• prek run --all-files: Run code quality checks.

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Resources

LUT Format

LUT stands for "Look Up Table", and in this context it refers to a set of gamma ramps that can be applied to a color space.

.lut files are expected to be raw Windows gamma ramps:

WORD ramp[3][256]

That means:

• 1536 bytes total
• 3 channels: red, green, blue
• 256 u16 entries per channel
• little-endian encoding

3D LUT files .cube are also supported, but they are converted to .lut files on the fly. So, if you have a 3D LUT file that is complex, the result might be a bit different from the original.