C# OpenCV学习笔记五之图像轮廓

原始图

轮廓图

相关代码如下

            Image imageSource = new Image((Bitmap)loadPictureBox.Image);
            Image imageGrayscale = imageSource.Convert();
            Image dest = new Image(imageGrayscale.Width, imageGrayscale.Height);

            CvInvoke.cvThreshold(imageGrayscale, dest, 30, 255, Emgu.CV.CvEnum.THRESH.CV_THRESH_BINARY);

            loadPictureBox.Image = dest.ToBitmap();

            IntPtr Dyncontour = new IntPtr();
            IntPtr Dynstorage = CvInvoke.cvCreateMemStorage(0);
            MCvContour con = new MCvContour();

            int n = CvInvoke.cvFindContours(dest, Dynstorage, ref Dyncontour, Marshal.SizeOf(con), Emgu.CV.CvEnum.RETR_TYPE.CV_RETR_TREE, Emgu.CV.CvEnum.CHAIN_APPROX_METHOD.CV_LINK_RUNS, new Point(0, 0));
            Seq DyncontourTemp = new Seq(Dyncontour, null);

            IntPtr dst = CvInvoke.cvCreateImage(CvInvoke.cvGetSize(dest), Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U, 3);
            CvInvoke.cvZero(dst);

            int areaTotal = 0;//求轮廓面积
            double max = 0;//求轮廓最大矩阵对角线
            for (; DyncontourTemp != null && DyncontourTemp.Ptr.ToInt32() != 0; DyncontourTemp = DyncontourTemp.HNext)
            {
                Rectangle r = DyncontourTemp.BoundingRectangle;
                double tmp = Math.Sqrt(r.Height * r.Height + r.Width * r.Width);
                if (tmp > max)
                {
                    max = tmp;
                }
                
                areaTotal += r.Width * r.Height;

                //画出轮廓
                CvInvoke.cvRectangle(dst, new Point(r.X, r.Y), new Point(r.X + r.Width, r.Y + r.Height), new MCvScalar(255, 0, 0), 1, Emgu.CV.CvEnum.LINE_TYPE.EIGHT_CONNECTED, 0);
            }
            MessageBox.Show("Area Total :" + areaTotal.ToString());
            MessageBox.Show("Max Dist : " + max.ToString());

            CvInvoke.cvNamedWindow("dst");
            CvInvoke.cvShowImage("dst", dst);

            IntPtr2Image(dst).Save("001-1.jpg");//保存轮廓图形