Emgu 学习(3) 绘图，使用鼠标绘图，使用trackbar

绘图

    class Program
    {
        static void Main(String[] args)
        {
            Mat img = new Mat(, , DepthType.Cv8U, );
            img.SetTo(new Bgr(, , ).MCvScalar);
            //绘制一条黄色，线宽为4 的反锯齿线段
            CvInvoke.Line(img, new Point(, ), new Point(, ), new MCvScalar(, , ),,LineType.AntiAlias);
            //绘制圆心为200,100，半径为50，线宽为15的红色空心圆
            CvInvoke.Circle(img, new Point(, ), , new MCvScalar(, , ), , LineType.AntiAlias);
            //绘制左上角200,300宽高为150,100的绿色矩形框
            CvInvoke.Rectangle(img, new Rectangle(, , , ), new MCvScalar(, , ), );
            //绘制中心为200,200，大小为150,120，旋转40度，颜色为cyan的椭圆
            CvInvoke.Ellipse(img, new RotatedRect(new Point(, ), new Size(, ), ), new MCvScalar(, , ), );
            //绘制文字
            CvInvoke.PutText(img, "CTC", new Point(, ), FontFace.HersheyComplex, , new MCvScalar(, , ), );

            CvInvoke.Imshow("draw", img);
            CvInvoke.WaitKey();

        }
    }

效果

使用鼠标绘制矩形

效果如下，使用鼠标中键拖拉矩形框。

中间黑色的控件是ImageBox，没有缩放

        Point pt = new Point();
        Mat frame = null;
        public Form1()
        {
            InitializeComponent();
            frame=new Mat(imageBox1.Height,imageBox1.Width, DepthType.Cv8U, );
            frame.SetTo(new Bgr(, , ).MCvScalar);
            CvInvoke.Line(frame, new Point(, ), new Point(, ), new MCvScalar(, , ), , LineType.AntiAlias);
            Application.Idle += Run;
        }

        private void Run(object sender,EventArgs e)
        {
            imageBox1.Image = frame;
        }

        private void imageBox1_MouseDown(object sender, MouseEventArgs e)
        {
            pt.X = e.X;
            pt.Y = e.Y;
        }

        private void imageBox1_MouseUp(object sender, MouseEventArgs e)
        {
            CvInvoke.Rectangle(frame, new Rectangle(pt.X, pt.Y, e.X-pt.X, e.Y-pt.Y), new MCvScalar(, , ), );
        }
    }

使用Trackbar调整数值threshold处理

    public partial class Form1 : Form
    {

        Mat src = null;
        Mat dst = new Mat();
        string path=@"C:\Users\dell\Pictures\mach.jpg";
        public Form1()
        {
            InitializeComponent();
            src = CvInvoke.Imread(path);
            imageBox1.Image = src;

        }

        private void trackBar1_ValueChanged(object sender, EventArgs e)
        {
            int value = trackBar1.Value;
            CvInvoke.Threshold(src, dst, value, , ThresholdType.Binary);
            imageBox1.Image = dst;
        }

    }