OpenCvSharp で色領域抽出 (めっちゃ C ライク)

ColorExtraction_c.cs

using OpenCvSharp;
using System;

namespace OpenCvSharpSample
{

    class Program
    {
        static void Main(string[] args)
        {
            // ファイル読み込み
            var srcImage = new IplImage("lena.jpg");

            var dstImage = new IplImage(srcImage.Size,srcImage.Depth,srcImage.NChannels);

            // 肌色領域を抽出
            ColorExtraction(srcImage,dstImage, ColorConversion.BgrToHsv, 0, 10, 80, 255, 0, 255);

            Cv.ShowImage("SrcMat", srcImage);
            Cv.ShowImage("SkinColor", dstImage);
            Cv.WaitKey(0);
        }

        public static void ColorExtraction(IplImage srcImage, IplImage dstImage, ColorConversion code,
        int ch1Lower, int ch1Upper,
        int ch2Lower, int ch2Upper,
        int ch3Lower, int ch3Upper)
        {

            if (srcImage == null)
                throw new ArgumentNullException("srcImage");
            else if (dstImage == null)
                throw new ArgumentNullException("dstImage");


            IplImage colorImage;
            IplImage ch1Image, ch2Image, ch3Image;
            IplImage maskImage;

            int i, k;
            int[] lower = new int[3];
            int[] upper = new int[3];
            int[] val = new int[3];

            CvMat lut;

            colorImage = Cv.CreateImage(Cv.GetSize(srcImage), srcImage.Depth, srcImage.NChannels);
            Cv.CvtColor(srcImage, colorImage, code);

            lut = Cv.CreateMat(256, 1, MatrixType.U8C3);

            lower[0] = ch1Lower;
            lower[1] = ch2Lower;
            lower[2] = ch3Lower;

            upper[0] = ch1Upper;
            upper[1] = ch2Upper;
            upper[2] = ch3Upper;

            for (i = 0; i < 256; i++)
            {
                for (k = 0; k < 3; k++)
                {
                    if (lower[k] <= upper[k])
                    {
                        if ((lower[k] <= i) && (i <= upper[k]))
                        {
                            val[k] = 255;
                        }
                        else
                        {
                            val[k] = 0;
                        }
                    }
                    else
                    {
                        if ((i <= upper[k]) || (lower[k] <= i))
                        {
                            val[k] = 255;
                        }
                        else
                        {
                            val[k] = 0;
                        }
                    }
                }
                Cv.Set1D(lut, i, new CvScalar(val[0], val[1], val[2]));
            }

            Cv.LUT(colorImage, colorImage, lut);
            Cv.ReleaseMat(lut);

            ch1Image = Cv.CreateImage(Cv.GetSize(colorImage), colorImage.Depth, 1);
            ch2Image = Cv.CreateImage(Cv.GetSize(colorImage), colorImage.Depth, 1);
            ch3Image = Cv.CreateImage(Cv.GetSize(colorImage), colorImage.Depth, 1);

            Cv.Split(colorImage, ch1Image, ch2Image, ch3Image, null);

            maskImage = Cv.CreateImage(Cv.GetSize(colorImage), colorImage.Depth, 1);
            Cv.And(ch1Image, ch2Image, maskImage);
            Cv.And(maskImage, ch3Image, maskImage);

            Cv.Zero(dstImage);
            Cv.Copy(srcImage, dstImage, maskImage);

            Cv.ReleaseImage(colorImage);
            Cv.ReleaseImage(ch1Image);
            Cv.ReleaseImage(ch2Image);
            Cv.ReleaseImage(ch3Image);
            Cv.ReleaseImage(maskImage);
        }
    }
}