rgb2xyz: RGB to CIE XYZ Color Space Conversion

Device-Independent Color Transformation

The rgb2xyz function converts RGB color values to the CIE XYZ color space, which serves as an intermediate step for color space transformations. XYZ space provides a device-independent representation based on human vision standardization.

Mathematical Foundation

The transformation uses the sRGB to CIE XYZ D65 standard matrix:

$$\begin{pmatrix} X \\ Y \\ Z \end{pmatrix} = \begin{pmatrix} 0.4125 & 0.3576 & 0.1804 \\ 0.2127 & 0.7152 & 0.0722 \\ 0.0193 & 0.1192 & 0.9503 \end{pmatrix} \begin{pmatrix} R \\ G \\ B \end{pmatrix}$$

This matrix assumes linear RGB values. The Y component represents luminance, while X and Z define chromaticity coordinates.

XYZ Chromaticity Decomposition

ライブエディター

const fragment = () => {
      const rgbColor = vec3(uv.x, uv.y, 0.5)
      const xyzColor = rgb2xyz(rgbColor)
      return vec4(xyzColor, 1)
}