Question

正在处理一个应用程序并试图从提供的基色中找到颜色（互补，分裂 - 互补，类似，三元组，四元组，方形等...）。

我现在在做什么：

将RGB颜色转换为HSV
调整H值以获得360度轮周围的颜色（S和V值不变）
将HSV转换回RGB

以下是Triad的示例（hsv对象代表基色）：

colors.Add(new HSVData() { h = hsv.h + 120, s = hsv.s, v = hsv.v });
colors.Add(new HSVData() { h = hsv.h - 120, s = hsv.s, v = hsv.v });

对于Square：

colors.Add(new HSVData() { h = hsv.h + 90, s = hsv.s, v = hsv.v });
colors.Add(new HSVData() { h = hsv.h + 180, s = hsv.s, v = hsv.v });
colors.Add(new HSVData() { h = hsv.h + 270, s = hsv.s, v = hsv.v });

RGB到HSV：

public static HSVData RGBtoHSV(RGBResult RGB)
{
    double min;
    double max;
    double delta;

    double r = (double)RGB.r / 255;
    double g = (double)RGB.g / 255;
    double b = (double)RGB.b / 255;

    double h;
    double s;
    double v;

    min = Math.Min(Math.Min(r, g), b);
    max = Math.Max(Math.Max(r, g), b);
    v = max;
    delta = max - min;
    if (max == 0 || delta == 0)
    {
        s = 0;
        h = 0;
    }
    else
    {
        s = delta / max;
        if (r == max)
        {
            // Between Yellow and Magenta
            h = (g - b) / delta;
        }
        else if (g == max)
        {
            // Between Cyan and Yellow
            h = 2 + (b - r) / delta;
        }
        else
        {
            // Between Magenta and Cyan
            h = 4 + (r - g) / delta;
        } 
    }

    h *= 60;
    if (h < 0)
    {
        h += 360;
    }

    return new HSVData()
    {
        h = (int)(h / 360 * 255),
        s = (int)(s * 255),
        v = (int)(v * 255)
    };
}

HSV到RGB：

public static Color ConvertHsvToRgb(float h, float s, float v)
{
    byte MAX = 255;

    h = h / 360;
    if (s > 0)
    {
        if (h >= 1)
            h = 0;
        h = 6 * h;
        int hueFloor = (int)Math.Floor(h);
        byte a = (byte)Math.Round(MAX * v * (1.0 - s));
        byte b = (byte)Math.Round(MAX * v * (1.0 - (s * (h - hueFloor))));
        byte c = (byte)Math.Round(MAX * v * (1.0 - (s * (1.0 - (h - hueFloor)))));
        byte d = (byte)Math.Round(MAX * v);

        switch (hueFloor)
        {
            case 0: return Color.FromArgb(MAX, d, c, a);
            case 1: return Color.FromArgb(MAX, b, d, a);
            case 2: return Color.FromArgb(MAX, a, d, c);
            case 3: return Color.FromArgb(MAX, a, b, d);
            case 4: return Color.FromArgb(MAX, c, a, d);
            case 5: return Color.FromArgb(MAX, d, a, b);
            default: return Color.FromArgb(0, 0, 0, 0);
        }
    }
    else
    {
        byte d = (byte)(v * MAX);
        return Color.FromArgb(255, d, d, d);
    }
}

根据许多在线颜色工具，我得到的颜色是错误的！我应该使用HSV的HSL吗？我做错了什么？

http://colorschemedesigner.com/

http://www.colorsontheweb.com/colorwizard.asp

提前致谢！

Answer 1

您希望在ConvertHsvToRgb方法中获得哪些值？它看起来像是：

0 <= h <= 360
0 <= s <= 1.0
0 <= v <= 1.0

您没有显示如何调用此方法，但如果您没有在这些范围内传递值，则无法获得正确的转换。如果你计划减去色调，你可能想要包括一种将色调归一化为0到360的方法，就像在三重奏中一样。

我认为您的转换是正确的，除非您不应将h，s，v值转换为整数;将它们保持为双倍，在上面显示的范围内。

public static HSVData RGBtoHSV(Color RGB)
{
    double r = (double)RGB.R / 255;
    double g = (double)RGB.G / 255;
    double b = (double)RGB.B / 255;

    double h;
    double s;
    double v;

    double min = Math.Min(Math.Min(r, g), b);
    double max = Math.Max(Math.Max(r, g), b);
    v = max;
    double delta = max - min;
    if (max == 0 || delta == 0)
    {
        s = 0;
        h = 0;
    }
    else
    {
        s = delta / max;
        if (r == max)
        {
            // Between Yellow and Magenta
            h = (g - b) / delta;
        }
        else if (g == max)
        {
            // Between Cyan and Yellow
            h = 2 + (b - r) / delta;
        }
        else
        {
            // Between Magenta and Cyan
            h = 4 + (r - g) / delta;
        }

    }

    h *= 60;
    if (h < 0)
    {
        h += 360;
    }

    return new HSVData()
    {
        h = h,
        s = s,
        v = v
    };
}

现在您可以将这些h，s，v valuew直接传递给ConvertHsvToRgb方法。我已将参数更改为double，验证饱和度和值输入，并将色调标准化。

public static Color ConvertHsvToRgb(double h, double s, double v)
{
    Debug.Assert(0.0 <= s && s <= 1.0);
    Debug.Assert(0.0 <= v && v <= 1.0);

    // normalize the hue:
    while (h < 0)
        h += 360;
    while (h > 360)
        h -= 360;

    h = h / 360;

    byte MAX = 255;

    if (s > 0)
    {
        if (h >= 1)
            h = 0;
        h = 6 * h;
        int hueFloor = (int)Math.Floor(h);
        byte a = (byte)Math.Round(MAX * v * (1.0 - s));
        byte b = (byte)Math.Round(MAX * v * (1.0 - (s * (h - hueFloor))));
        byte c = (byte)Math.Round(MAX * v * (1.0 - (s * (1.0 - (h - hueFloor)))));
        byte d = (byte)Math.Round(MAX * v);

        switch (hueFloor)
        {
            case 0: return Color.FromArgb(MAX, d, c, a);
            case 1: return Color.FromArgb(MAX, b, d, a);
            case 2: return Color.FromArgb(MAX, a, d, c);
            case 3: return Color.FromArgb(MAX, a, b, d);
            case 4: return Color.FromArgb(MAX, c, a, d);
            case 5: return Color.FromArgb(MAX, d, a, b);
            default: return Color.FromArgb(0, 0, 0, 0);
        }
    }
    else
    {
        byte d = (byte)(v * MAX);
        return Color.FromArgb(255, d, d, d);
    }
}

根据我的测试，这两种方法现在可以为从RGB到HSV再返回的任何颜色进行“往返”转换。

对于“三重奏”，您正在调整原始颜色+/- 120度。因此，例如，如果您以红色作为基色开始，则+/- 120度颜色为绿色和蓝色。这些转化似乎可以正常运行：

HSVData hsv = HSVData.RGBtoHSV(Color.FromArgb(255, 0, 0));
HSVData hsv2 = new HSVData() { h = hsv.h + 120, s = hsv.s, v = hsv.v };
HSVData hsv3 = new HSVData() { h = hsv.h - 120 , s = hsv.s, v = hsv.v };

Color red = HSVData.ConvertHsvToRgb(hsv.h, hsv.s, hsv.v);
Color green = HSVData.ConvertHsvToRgb(hsv2.h, hsv2.s, hsv2.v);
Color blue = HSVData.ConvertHsvToRgb(hsv3.h, hsv3.s, hsv3.v);

HSVData hsv4 = HSVData.RGBtoHSV(Color.YellowGreen);
Color yellowGreen = HSVData.ConvertHsvToRgb(hsv4.h, hsv4.s, hsv4.v);

颜色和谐理论与算法，计算互补，三元组，四元组等

1 个答案: