如何在EmguCV中将Bgr像素转换为Hsv像素？

Question

I'd like to convert a Bgr value (one pixel) to an Hsv value. How can I do that (without writing the conversion code from scratch) in EmguCV?

Please note that I am not interested in converting whole image's color space but only one pixel, therefore CvInvoke.cvCvtColor() does not work for me.

Answer 1

Okay I already found a way using some help from .NET framework

given a Bgr pixel ;

1- Converting the color to System.Drawing.Color :

System.Drawing.Color intermediate = System.Drawing.Color.FromArgb((int)pixel.Red, (int)pixel.Green, (int)pixel.Blue);

2- Constructing Hsv from the intermediate.

Hsv hsvPixel = new Hsv(intermediate.GetHue(), intermediate.GetSaturation(), intermediate.GetBrightness());

Cheers.

Answer 2

If you want to do this within EmguCV just read the image into a Image the get the value of the pixel and stick it in a Hsv structure.

For example:

static void Main(string[] args)
{
    bool haveOpenCL = CvInvoke.HaveOpenCL;

    bool haveOpenClGpu = CvInvoke.HaveOpenCLCompatibleGpuDevice;

    CvInvoke.UseOpenCL = true;

    Emgu.CV.Image<Bgr, Byte> lenaBgr = new Image<Bgr, Byte>(@"D:\OpenCV\opencv-3.2.0\samples\data\Lena.jpg");

    CvInvoke.Imshow("Lena BSG", lenaBgr);

    Bgr color = lenaBgr[100, 100];

    Console.WriteLine("Bgr: {0}", color.ToString());

    Emgu.CV.Image<Hsv, Byte> lenaHsv = new Image<Hsv, Byte>(@"D:\OpenCV\opencv-3.2.0\samples\data\Lena.jpg");

    CvInvoke.Imshow("Lena HSV", lenaHsv);

    Hsv colorHsv = lenaHsv[100, 100];

    Console.WriteLine("HSV: {0}", colorHsv.ToString());

    CvInvoke.WaitKey(0);
}

}

The result: Bgr: [87,74,182] HSV: [176,151,182]

 Lena BGR                    Lena HSV