RGB to CIE color conversion [duplicate]

Question

As I said before (RGB to Philips Hue (HSB)) I'm still not giving up my hopes for converting a simple RGB value to a value Philips Hue will accept.

The official App for iPhone and Android allows you to select a color from a random photo and the Hue will adjust itself accordingly. So there must be some sort of formula.

This time however I think I have just found this very formula in this interesting article online:

https://github.com/PhilipsHue/PhilipsHueSDK-iOS-OSX/blob/master/ApplicationDesignNotes/RGB%20to%20xy%20Color%20conversion.md

I have been trying to convert his explanation to Java language, but I'm not getting the desired results. Anybody knows what goes wrong?

For the record I'm using the Philips Hue Light Bulbs.

public static List<Double> getRGBtoXY(Color c) {
        // For the hue bulb the corners of the triangle are:
        // -Red: 0.675, 0.322
        // -Green: 0.4091, 0.518
        // -Blue: 0.167, 0.04
        double[] normalizedToOne = new double[3];
        float cred, cgreen, cblue;
        cred = c.getRed();
        cgreen = c.getGreen();
        cblue = c.getBlue();
        normalizedToOne[0] = (cred / 255);
        normalizedToOne[1] = (cgreen / 255);
        normalizedToOne[2] = (cblue / 255);
        float red, green, blue;

        // Make red more vivid
        if (normalizedToOne[0] > 0.04045) {
            red = (float) Math.pow(
                    (normalizedToOne[0] + 0.055) / (1.0 + 0.055), 2.4);
        } else {
            red = (float) (normalizedToOne[0] / 12.92);
        }

        // Make green more vivid
        if (normalizedToOne[1] > 0.04045) {
            green = (float) Math.pow((normalizedToOne[1] + 0.055)
                    / (1.0 + 0.055), 2.4);
        } else {
            green = (float) (normalizedToOne[1] / 12.92);
        }

        // Make blue more vivid
        if (normalizedToOne[2] > 0.04045) {
            blue = (float) Math.pow((normalizedToOne[2] + 0.055)
                    / (1.0 + 0.055), 2.4);
        } else {
            blue = (float) (normalizedToOne[2] / 12.92);
        }

        float X = (float) (red * 0.649926 + green * 0.103455 + blue * 0.197109);
        float Y = (float) (red * 0.234327 + green * 0.743075 + blue + 0.022598);
        float Z = (float) (red * 0.0000000 + green * 0.053077 + blue * 1.035763);

        float x = X / (X + Y + Z);
        float y = Y / (X + Y + Z);

        double[] xy = new double[2];
        xy[0] = x;
        xy[1] = y;
        List<Double> xyAsList = Doubles.asList(xy);
        return xyAsList;
    }

This is not a duplicate? Please read the referenced question to fully understand. This is a question to convert to XY. The referenced question is about converting RGB to HSB. How can this be the same?!?!

As

bmargulies, Wyzard, Robby Pond, Kevin Panko, msandiford How is this a duplicate please let me hear your explanation? – As

Did correcting the typo fix things? If so, then this question should still be closed as "too localized"---meaning that no one else is likely to have the same typo as you and thus no one else will benefit from the answer. But if not, this question should be re-opened, because xy conversion is not the same as HSB conversion. – Colossus

Answer 1

Found one little mistake:

float Y = (float) (red * 0.234327 + green * 0.743075 + blue + 0.022598);

should be

float Y = (float) (red * 0.234327 + green * 0.743075 + blue * 0.022598);

Intwine