Color Managed WPF Demonstration app based on the nuget library Mscms
Colors displayed by WPF applications are not color managed, this library fills the gap by integrating the WCS (Windows Color System) introduced by Windows Vista.
The first step for accurate colors is to calibrate the monitor with a calibration software (ex. DisplayCal) and device (manufacturer ex. Calibrite, Datacolor, etc..). A Color Profile for your monitor will be installed.
As an example the Color Profile may contains data to map the sRGB color (255,0,0) to the value RGB (240,0,0) if you monitor is able to display a RED that is more saturated than the RED defined by the sRGB standard.
After this step color-managed apps (ex. Photoshop) can use the installed Color Profile to display accurate colors.
What about other apps? They show partially corrected colors because only some corrections (ex. Gamma Curve 1D LUT) are loaded into the GPU and OS-independent.
Because WCS is integrated in the OS and supports advanced Color Profiles containing LUTs, Matrix, etc.. that other Color Engines (for ex. the one used by Gimp) are not able to fully process. LittleCMS is a common alternative for C/C++ softwares.
The whole app is not automatically color-managed because there is no usually need for this. Only images or specific parts need to be color-managed. To manage Colors and Images two extension methods are provided: ToManagedColor() and ToManagedImage().
Color managed = Color.FromRgb(248, 218, 69).ToManagedColor();
BitmapImage managedImage = new BitmapImage(..).ToManagedImage();
This is the simplest way to automatically translate colors with the Color Profile associated to the monitor hosting the app.
Additional classes are available to specify the Input/Output Profile, the Rendering Intent and additional options. This application contains an Advanced example to show these classes and how to update the Color Profile if the app is moved to another monitor.
If it's best not to touch your application code, an Attached Property is available for the Image control and the SolidColorBrush class. Can be used by simply adding the IsColorManaged property to your XAML.
<Image Mscms:WpfManagedColors.IsColorManaged="True" />
A FullHD image (1920x1080) color correction usually takes less than 0.1s
For high-performance scenario a commercial version of the Mscms.WPF library exists and offers a GPU-accelerated color management engine, making possible to color-manage the whole app with support for real-time animations, video playback, etc.. Please contact the author if interested.
To verify the real-world accuracy of the Mscms Color Management a Target Color was displayed and measured under different conditions.
| Monitor | Calibration Hardware | Calibration Software |
|---|---|---|
| LG 27UK650 | X-Rite ColorMunki Display | DisplayCal 3.8.9.3 |
The native RGB color space of the Monitor is wider than sRGB and color-unmanaged applications will display overly saturated colors. This can be a serious problem for applications that requires accurate colors for decision making such as medical software, quality control, imaging applications, product stores, etc..
Note: The above 2D diagram, calculated with the Perceptual Rendering Intent, can give only an idea of what colors the monitor is able to reproduce in the LAB color space that is 3D.
| sRGB | LAB D50 |
|---|---|
| 248 218 69 | 87.73 -0.36 72.62 |
| Monitor | App Colors | Measured sRGB | Measured LAB D50 | CIE00 | CMC 1:1 |
|---|---|---|---|---|---|
| Uncalibrated | Unmanaged | 245 224 6 | 88.82 -5.67 86.44 | 4.16 | 5.43 |
| Calibrated | Unmanaged | 247 218 35 | 87.60 -1.51 82.00 | 2.19 | 3.18 |
| Calibrated | Managed | 250 219 76 | 88.24 -0.02 70.52 | 0.63 | 0.80 |
An uncalibrated monitor is showing a color difference of 4.16 using the CIE2000 comparison method. The difference is easily spotted by untrained viewers.
By calibrating the monitor some corrections are loaded in the GPU the color accuracy improves to 2.19. The difference is still spottable.
The color-managed WPF app with the calibrated monitor is showing an unperceptible color difference of 0.63. Trained viewers are usually not able to discern any difference.
How the target color looks under different conditions
Note: To properly see the comparison, the image should be viewed on a calibrated sRGB monitor, in standard environment conditions and with a color-managed application. Some browsers (ex. Firefox) are not color-managing non-tagged images by default.
Results may differ depending on the Monitor, the Calibration and the displayed color, but the concept and order of magnitude remains valid.
By calibrating the monitor and using a color-managed app, the average CIE2000 color difference of tested colors is within 0.8
The Monitor is calibrated and the Color Profile is installed. In this example you can see that the Managed Yellow is slightly different to be more accurate on the used display. Colors are transformed from the Input Profile (sRGB) to the Output Profile (Monitor profile .icm)
The Monitor is not calibrated and the Color Profile fallback to sRGB. Colors are not changed because Input and Output profiles are the same.
The library is divided in two packages: Mscms.Core (.NET Standard 2.0) and Mscms.WPF (.NET 4.8 Framework) to support any modern .NET application.
WPF projects (including .NET 6+) should reference Mscms.WPF, while non-WPF projects (ASP.NET, UWP, MAUI, etc..) should reference the Mscms.Core library.
The library Mscms is not free to use for commercial projects. Please contact (info at majinsoft .com) to obtain a commercial license, support and additional features such as GPU acceleration.