private static void Solve(float x1, float x2, float x3, ColorRGB rgb1, ColorRGB rgb2, ColorRGB rgb3, out float m1, out float m2, out float m3)
{
// Cramer's rule
ColorTransformMatrix A = new ColorTransformMatrix
(
rgb1.R, rgb1.G, rgb1.B,
rgb2.R, rgb2.G, rgb2.B,
rgb3.R, rgb3.G, rgb3.B
);
ColorTransformMatrix A1 = new ColorTransformMatrix
(
x1, rgb1.G, rgb1.B,
x2, rgb2.G, rgb2.B,
x3, rgb3.G, rgb3.B
);
ColorTransformMatrix A2 = new ColorTransformMatrix
(
rgb1.R, x1, rgb1.B,
rgb2.R, x2, rgb2.B,
rgb3.R, x3, rgb3.B
);
ColorTransformMatrix A3 = new ColorTransformMatrix
(
rgb1.R, rgb1.G, x1,
rgb2.R, rgb2.G, x2,
rgb3.R, rgb3.G, x3
);
float det = A.Determinant;
m1 = A1.Determinant / det;
m2 = A2.Determinant / det;
m3 = A3.Determinant / det;
}
public static Color1931XYZ ToXYZ(this ColorHSV HSV, ColorTransformMatrix RGBtoXYZ)
{
ColorRGB RGB = ToRGB(HSV);
return(ToXYZ(HSV, RGBtoXYZ));
}
public static Chromaticity1976uv Touv(this ColorRGB RGB, ColorTransformMatrix RGBtoXYZ)
{
Color1931XYZ XYZ = ToXYZ(RGB, RGBtoXYZ);
return(Touv(XYZ));
}
public static Chromaticity1931xy Toxy(this ColorHSV HSV, ColorTransformMatrix RGBtoXYZ)
{
ColorRGB RGB = ToRGB(HSV);
return(Toxy(RGB, RGBtoXYZ));
}
public static Color1976Lab ToLab(this ColorRGB RGB, ColorTransformMatrix RGBtoXYZ, Color1931XYZ whiteLab)
{
Color1931XYZ XYZ = ToXYZ(RGB, RGBtoXYZ);
return(ToLab(XYZ, whiteLab));
}
public static Color1931xyY ToxyY(this ColorRGB RGB, ColorTransformMatrix RGBtoXYZ)
{
Color1931XYZ XYZ = ToXYZ(RGB, RGBtoXYZ);
return(ToxyY(XYZ));
}
public static ColorTransformMatrix GetXYZtoRGB(Color1931XYZ xyz1, Color1931XYZ xyz2, Color1931XYZ xyz3, ColorRGB rgb1, ColorRGB rgb2, ColorRGB rgb3)
{
return(GetRGBtoXYZ(xyz1, xyz2, xyz3, rgb1, rgb2, rgb3).Invert());
}
public static ColorTransformMatrix GetRGBtoXYZ(Color1931XYZ xyz1, Color1931XYZ xyz2, Color1931XYZ xyz3, ColorRGB rgb1, ColorRGB rgb2, ColorRGB rgb3)
{
float a, b, c;
float d, e, f;
float g, h, i;
Solve(xyz1.X, xyz2.X, xyz3.X, rgb1, rgb2, rgb3, out a, out b, out c);
Solve(xyz1.Y, xyz2.Y, xyz3.Y, rgb1, rgb2, rgb3, out d, out e, out f);
Solve(xyz1.Z, xyz2.Z, xyz3.Z, rgb1, rgb2, rgb3, out g, out h, out i);
return(new ColorTransformMatrix(a, b, c, d, e, f, g, h, i));
}