Template Match Demo

출처: https://github.com/shimat/opencvsharp/issues/182

 
using static System.Console;
using OpenCvSharp;
using OpenCvSharp.Util;
static void RunTemplateMatch(string reference, string template)
{
    using (Mat refMat = new Mat(reference))
    using (Mat tplMat = new Mat(template))
    using (Mat res = new Mat(refMat.Rows - tplMat.Rows + 1, refMat.Cols - tplMat.Cols + 1, MatType.CV_32FC1))
    {
        //Convert input images to gray
        Mat gref = refMat.CvtColor(ColorConversionCodes.BGR2GRAY);
        Mat gtpl = tplMat.CvtColor(ColorConversionCodes.BGR2GRAY);

        Cv2.MatchTemplate(gref, gtpl, res, TemplateMatchModes.CCoeffNormed);
        Cv2.Threshold(res, res, 0.8, 1.0, ThresholdTypes.Tozero);

        while (true)
        {
            double minval, maxval, threshold = 0.8;
            Point minloc, maxloc;
            Cv2.MinMaxLoc(res, out minval, out maxval, out minloc, out maxloc);

            if (maxval >= threshold)
            {
                //Setup the rectangle to draw
                Rect r = new Rect(new Point(maxloc.X, maxloc.Y), new Size(tplMat.Width, tplMat.Height));
                WriteLine($"MinVal={minval.ToString()} MaxVal={maxval.ToString()} MinLoc={minloc.ToString()} MaxLoc={maxloc.ToString()} Rect={r.ToString()}");

                //Draw a rectangle of the matching area
                Cv2.Rectangle(refMat, r, Scalar.LimeGreen, 2);

                //Fill in the res Mat so you don't find the same area again in the MinMaxLoc
                Rect outRect;
                Cv2.FloodFill(res, maxloc, new Scalar(0), out outRect, new Scalar(0.1), new Scalar(1.0));
            }
            else
                break;
        }

        Cv2.ImShow("Matches", refMat);
        Cv2.WaitKey();
    }
}