已经用BH1745读出了RGB值怎么转换为光波长

Question

已经用BH1745读出了RGB值 ， 怎么将其转换为光波长？恳请各位大伽赐教。 谢谢

Answer 1

我已经找到解决算法， 谢谢大家。

double BH1745NUC::rgb_to_wavelength(int R, int G, int B) 
{
    double gamma = 0.8;
    double R_linear = pow((R + 0.055) / 1.055, gamma);
    double G_linear = pow((G + 0.055) / 1.055, gamma);
    double B_linear = pow((B + 0.055) / 1.055, gamma);

    double X = 0.4124564 * R_linear + 0.3575761 * G_linear + 0.1804375 * B_linear;
    double Y = 0.2126729 * R_linear + 0.7151522 * G_linear + 0.0721750 * B_linear;
    double Z = 0.0193339 * R_linear + 0.1191920 * G_linear + 0.9503041 * B_linear;

    // CIE XYZ to CIE xyY conversion
    double x = X / (X + Y + Z);
    double y = Y / (X + Y + Z);

    // xyY to wavelength (in nanometers) conversion
    double wavelength = -1;

    if (x >= 0.185 && x <= 0.452 && y >= 0.188 && y <= 0.538) {
        wavelength = 449 + (x - 0.185) / (0.452 - 0.185) * (621 - 449);
    } else if (x >= 0.317 && x <= 0.478 && y >= 0.337 && y <= 0.607) {
        wavelength = 495 + (x - 0.317) / (0.478 - 0.317) * (570 - 495);
    } else if (x >= 0.239 && x <= 0.513 && y >= 0.155 && y <= 0.418) {
        wavelength = 569 + (x - 0.239) / (0.513 - 0.239) * (513 - 569);
    }

    return wavelength;
}