java - RGB 转飞利浦 Hue (HSB)

Question

我正在为一项学校作业在 Processing 中制作音乐播放器。飞利浦Hue灯会做出一些相应的视觉效果。我想让每首歌的视觉效果都独一无二。因此，我获取了播放轨道的封面艺术(使用 LastFM API)以获得最常见的颜色，并将其用作创建其他颜色的基础。飞利浦 Hue 有一种不同的显示颜色的方式，即 (HSB)。所以我通过

转换了它

Color.RGBtoHSB();

例如。它为我提供了 R= 127、G=190、B=208 的值 H= 0.5370371、S=0.38942307、B=0.8156863。现在我猜它们是基于 1 计算的，所以我将亮度和饱和度乘以 255。色相乘以 65535。(如 http://developers.meethue.com/1_lightsapi.html 中所见)

在 Philips Hue 中设置这些计算值时，无论播放什么歌曲，颜色始终偏红或偏白。

RGB 到 HSB 的转换有问题吗？

应大众要求我的代码:

作为测试:

Color c = Colorconverter.getMostCommonColour("urltoimage");
float[] f = Colorconverter.getRGBtoHSB(c);
ArrayList<Lamp> myLamps = PhilipsHue.getInstance().getMyLamps();
State state = new State();
state.setBri((int) Math.ceil(f[2]*255));
state.setSat((int) Math.ceil(f[1]*255));
state.setHue((int) Math.ceil(f[0]*65535));
state.setOn(true);
PhilipsHue.setState(myLamps.get(1), state);

上面的函数

    public static Color getMostCommonColour(String coverArtURL) {
            Color coulourHex = null;
            try {
                BufferedImage image = ImageIO.read(new URL(coverArtURL));
                int height = image.getHeight();
                int width = image.getWidth();

                Map m = new HashMap();
                for (int i = 0; i < width; i++) {
                    for (int j = 0; j < height; j++) {
                        int rgb = image.getRGB(i, j);
                        int[] rgbArr = getRGBArr(rgb);
                        // No grays ...
                        if (!isGray(rgbArr)) {
                            Integer counter = (Integer) m.get(rgb);
                            if (counter == null) {
                                counter = 0;
                            }
                            counter++;
                            m.put(rgb, counter);
                        }
                    }
                }

                coulourHex = getMostCommonColour(m);
                System.out.println(coulourHex);
            } catch (IOException e) {
                e.printStackTrace();
            }
            return coulourHex;
        }

    private static Color getMostCommonColour(Map map) {
            List list = new LinkedList(map.entrySet());
            Collections.sort(list, new Comparator() {
                public int compare(Object o1, Object o2) {
                    return ((Comparable) ((Map.Entry) (o1)).getValue())
                            .compareTo(((Map.Entry) (o2)).getValue());
                }
            });
            Map.Entry me = (Map.Entry) list.get(list.size() - 1);
            int[] rgb = getRGBArr((Integer) me.getKey());
            String r = Integer.toHexString(rgb[0]);
            String g = Integer.toHexString(rgb[1]);
            String b = Integer.toHexString(rgb[2]);
            Color c = new Color(rgb[0], rgb[1], rgb[2]);
            return c;
        }
private static int[] getRGBArr(int pixel) {
        int alpha = (pixel >> 24) & 0xff;
        int red = (pixel >> 16) & 0xff;
        int green = (pixel >> 8) & 0xff;
        int blue = (pixel) & 0xff;
        return new int[] { red, green, blue };

    }

    private static boolean isGray(int[] rgbArr) {
        int rgDiff = rgbArr[0] - rgbArr[1];
        int rbDiff = rgbArr[0] - rgbArr[2];
        // Filter out black, white and grays...... (tolerance within 10 pixels)
        int tolerance = 10;
        if (rgDiff > tolerance || rgDiff < -tolerance)
            if (rbDiff > tolerance || rbDiff < -tolerance) {
                return false;
            }
        return true;
    }

    public static float[] getRGBtoHSB(Color c) {
        float[] hsv = new float[3];
        return Color.RGBtoHSB(c.getRed(), c.getGreen(), c.getBlue(), hsv);
    }

设置状态只是对飞利浦灯泡进行了简单的设置。当我检查受影响的灯泡上的 JSON 时

{
    "state": {
        "on": true,
        "bri": 81,
        "hue": 34277,
        "sat": 18,
        "xy": [
            0.298,
            0.2471
        ],
        "ct": 153,
        "alert": "none",
        "effect": "none",
        "colormode": "hs",
        "reachable": true
    },
    "type": "Extended color light",
    "name": "Hue Spot 1",
    "modelid": "LCT003",
    "swversion": "66010732",
    "pointsymbol": {
        "1": "none",
        "2": "none",
        "3": "none",
        "4": "none",
        "5": "none",
        "6": "none",
        "7": "none",
        "8": "none"
    }
}

Answer 1

特别感谢 StackOverflow 用户 Gee858eeG 注意到我的打字错误，并感谢 Erickson 提供的重要提示和链接。

这是一个可以将任何 RGB 颜色转换为 Philips Hue XY 值的工作函数。返回的列表只包含两个元素 0 是 X，1 是 Y。代码基于这个精彩的注释:https://github.com/PhilipsHue/PhilipsHueSDK-iOS-OSX/commit/f41091cf671e13fe8c32fcced12604cd31cceaf3

尽管这不会返回 HSB 值，但 XY 值可以用作在 Hue 上更改颜色的替代品。希望它能对其他人有所帮助，因为 Philips 的 API 没有提及任何公式。

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;
}