Skip to main content
The Virtual Display Driver provides advanced color management through configurable color spaces, gamma correction, and precise chromaticity coordinates.

​
Color Space Configuration

Configure color space settings in the hdr_advanced section: 
<hdr_advanced>
  <color_space>
    <enabled>true</enabled>
    <gamma_correction>2.4</gamma_correction>
    <primary_color_space>Rec.2020</primary_color_space>
    <enable_matrix_transform>true</enable_matrix_transform>
  </color_space>
</hdr_advanced>
​
enabled
boolean
default:"false"
Enable advanced color space processing. When disabled, driver uses default sRGB.
​
gamma_correction
double
default:"2.4"
Gamma curve exponent. Common values:
  • 2.2 - sRGB standard gamma
  • 2.4 - Rec.2020/HDR gamma
  • 2.6 - DCI-P3 cinema gamma
​
primary_color_space
enum
default:"sRGB"
Primary color space selection:
  • sRGB - Standard RGB (most compatible)
  • Rec.709 - HD video standard (identical to sRGB)
  • Rec.2020 - UHD/HDR wide gamut
  • DCI-P3 - Digital cinema wide gamut
  • Adobe_RGB - Photography wide gamut
​
enable_matrix_transform
boolean
default:"false"
Enable 3×4 color space transformation matrix for advanced color conversion.

​
Supported Color Spaces

​
sRGB (Standard RGB)

<color_space>
  <enabled>true</enabled>
  <gamma_correction>2.2</gamma_correction>
  <primary_color_space>sRGB</primary_color_space>
</color_space>
Characteristics:
  • Gamma: 2.2
  • White point: D65 (0.3127, 0.3290)
  • Most widely supported
  • Best compatibility

​
Rec.2020 (UHD/HDR)

<color_space>
  <enabled>true</enabled>
  <gamma_correction>2.4</gamma_correction>
  <primary_color_space>Rec.2020</primary_color_space>
  <enable_matrix_transform>true</enable_matrix_transform>
</color_space>
Characteristics:
  • Gamma: 2.4 (PQ or HLG for HDR)
  • Widest color gamut
  • Required for HDR10
  • Requires 10-bit color depth

​
DCI-P3 (Digital Cinema)

<color_space>
  <enabled>true</enabled>
  <gamma_correction>2.6</gamma_correction>
  <primary_color_space>DCI-P3</primary_color_space>
  <enable_matrix_transform>true</enable_matrix_transform>
</color_space>
Characteristics:
  • Gamma: 2.6
  • Wide gamut (between sRGB and Rec.2020)
  • Common for content creation
  • Requires 10-bit color depth

​
Color Primaries

Define precise chromaticity coordinates for custom color spaces: 
<hdr_advanced>
  <color_primaries>
    <enabled>true</enabled>
    <red_x>0.708</red_x>
    <red_y>0.292</red_y>
    <green_x>0.170</green_x>
    <green_y>0.797</green_y>
    <blue_x>0.131</blue_x>
    <blue_y>0.046</blue_y>
    <white_x>0.3127</white_x>
    <white_y>0.3290</white_y>
  </color_primaries>
</hdr_advanced>

​
Standard Primaries

sRGB/Rec.709: 
<red_x>0.640</red_x>   <red_y>0.330</red_y>
<green_x>0.300</green_x> <green_y>0.600</green_y>
<blue_x>0.150</blue_x>  <blue_y>0.060</blue_y>
<white_x>0.3127</white_x> <white_y>0.3290</white_y>  <!-- D65 -->
Rec.2020: 
<red_x>0.708</red_x>   <red_y>0.292</red_y>
<green_x>0.170</green_x> <green_y>0.797</green_y>
<blue_x>0.131</blue_x>  <blue_y>0.046</blue_y>
<white_x>0.3127</white_x> <white_y>0.3290</white_y>  <!-- D65 -->
DCI-P3: 
<red_x>0.680</red_x>   <red_y>0.320</red_y>
<green_x>0.265</green_x> <green_y>0.690</green_y>
<blue_x>0.150</blue_x>  <blue_y>0.060</blue_y>
<white_x>0.3127</white_x> <white_y>0.3290</white_y>  <!-- D65 -->
Color primaries are converted to SMPTE ST.2086 format (0-50000 range) for HDR metadata. See Driver.cpp:851-857 for conversion logic.

​
Gamma Correction

Gamma correction controls the brightness curve of the display:

​
Standard Gamma Values

GammaUse CaseDescription
2.2sRGBStandard computer displays
2.4Rec.2020HDR/UHD content
2.6DCI-P3Digital cinema
1.0LinearNo correction (raw data)

​
Custom Gamma Configuration

<color_space>
  <enabled>true</enabled>
  <gamma_correction>2.35</gamma_correction>  <!-- Custom value -->
  <primary_color_space>sRGB</primary_color_space>
</color_space>

​
Color Space Transformation Matrix

When enable_matrix_transform is enabled, the driver generates a 3×4 color space transformation matrix: 
// Matrix structure (Driver.cpp:681-684)
struct VddColorMatrix {
    FLOAT matrix[3][4];  // 3x4 transformation matrix
    bool isValid;
};

​
Matrix Generation

The driver automatically generates conversion matrices (Driver.cpp:700-759): sRGB to sRGB (identity with gamma): 
[γ/2.2,  0,      0,      0]
[0,      γ/2.2,  0,      0]
[0,      0,      γ/2.2,  0]
DCI-P3 to sRGB: 
[1.2249*(γ/2.4), -0.2247,         0,               0]
[-0.0420,         1.0419*(γ/2.4), 0,               0]
[-0.0196,        -0.0786,         1.0982*(γ/2.4),  0]
Rec.2020 to sRGB: 
[1.7347*(γ/2.4), -0.7347,         0,               0]
[-0.1316,         1.1316*(γ/2.4), 0,               0]
[-0.0241,        -0.1289,         1.1530*(γ/2.4),  0]
Matrix transforms require significant GPU processing. Only enable for wide gamut color spaces (DCI-P3, Rec.2020) when necessary.

​
Automatic Bit Depth Selection

The driver can automatically select bit depth based on color space: 
<color_advanced>
  <bit_depth_management>
    <auto_select_from_color_space>true</auto_select_from_color_space>
  </bit_depth_management>
</color_advanced>
Automatic selection logic (Driver.cpp:798-823):
  • Rec.2020 → 10-bit
  • DCI-P3 → 10-bit
  • Adobe_RGB → 10-bit
  • sRGB/Rec.709 → 8-bit

​
Configuration Examples

​
HDR10 Wide Gamut Setup

<hdr_advanced>
  <color_space>
    <enabled>true</enabled>
    <gamma_correction>2.4</gamma_correction>
    <primary_color_space>Rec.2020</primary_color_space>
    <enable_matrix_transform>true</enable_matrix_transform>
  </color_space>
  
  <color_primaries>
    <enabled>true</enabled>
    <red_x>0.708</red_x>
    <red_y>0.292</red_y>
    <green_x>0.170</green_x>
    <green_y>0.797</green_y>
    <blue_x>0.131</blue_x>
    <blue_y>0.046</blue_y>
    <white_x>0.3127</white_x>
    <white_y>0.3290</white_y>
  </color_primaries>
</hdr_advanced>

<color_advanced>
  <bit_depth_management>
    <auto_select_from_color_space>true</auto_select_from_color_space>
  </bit_depth_management>
</color_advanced>

​
Professional sRGB Setup

<hdr_advanced>
  <color_space>
    <enabled>true</enabled>
    <gamma_correction>2.2</gamma_correction>
    <primary_color_space>sRGB</primary_color_space>
    <enable_matrix_transform>false</enable_matrix_transform>
  </color_space>
  
  <color_primaries>
    <enabled>true</enabled>
    <red_x>0.640</red_x>
    <red_y>0.330</red_y>
    <green_x>0.300</green_x>
    <green_y>0.600</green_y>
    <blue_x>0.150</blue_x>
    <blue_y>0.060</blue_y>
    <white_x>0.3127</white_x>
    <white_y>0.3290</white_y>
  </color_primaries>
</hdr_advanced>

​
Cinema DCI-P3 Setup

<hdr_advanced>
  <color_space>
    <enabled>true</enabled>
    <gamma_correction>2.6</gamma_correction>
    <primary_color_space>DCI-P3</primary_color_space>
    <enable_matrix_transform>true</enable_matrix_transform>
  </color_space>
  
  <color_primaries>
    <enabled>true</enabled>
    <red_x>0.680</red_x>
    <red_y>0.320</red_y>
    <green_x>0.265</green_x>
    <green_y>0.690</green_y>
    <blue_x>0.150</blue_x>
    <blue_y>0.060</blue_y>
    <white_x>0.3127</white_x>
    <white_y>0.3290</white_y>
  </color_primaries>
</hdr_advanced>

<color_advanced>
  <bit_depth_management>
    <force_bit_depth>10</force_bit_depth>
  </bit_depth_management>
</color_advanced>

​
EDID Integration

Color profiles can be automatically loaded from EDID files: 
<edid_integration>
  <enabled>true</enabled>
  <auto_configure_from_edid>true</auto_configure_from_edid>
</edid_integration>
The driver extracts from monitor_profile.xml:
  • Color primaries (chromaticity coordinates)
  • Gamma value
  • Primary color space name
  • White point
See Custom EDID for details.

​
SDR White Level

Configure SDR white level for HDR displays: 
<color_advanced>
  <color_format_extended>
    <sdr_white_level>80.0</sdr_white_level>
  </color_format_extended>
</color_advanced>
Standard values:
  • 80 nits - Standard SDR on HDR displays
  • 100 nits - Brighter SDR content
  • 120 nits - Maximum recommended
SDR white level is used when displaying SDR content on HDR-capable displays to maintain consistent brightness.

​
Verification

Enable logging to verify color configuration: 
<logging>
  <logging>true</logging>
  <debuglogging>true</debuglogging>
</logging>
Log output shows: 
[INFO] Generated Gamma Ramp from EDID profile:
  Gamma: 2.4 (from 2.400)
  Color Space: Rec.2020
  Matrix Transform: Enabled
  3x4 Matrix:
    [1.73, -0.73, 0.00, 0.00]
    [-0.13, 1.13, 0.00, 0.00]
    [-0.02, -0.13, 1.15, 0.00]

​
Windows Requirements

Advanced color management requires:
  • Windows 10 version 1803 or later for wide gamut support
  • IddCx 1.4 or later for matrix transforms
  • Compatible GPU with color space conversion support

Build docs developers (and LLMs) love

Get started for freeTalk to us