1，首先要安装OpenCvSharp,使用cv2的函数获取设备，并将图像转换到Bitmap

  using OpenCvSharp;
  using OpenCvSharp.Extensions;    
 
 
 
     void run_cap()
        {
            Mat src = new Mat();
            FrameSource frame = Cv2.CreateFrameSource_Camera(0);
            while (f1)
            {
 
                frame.NextFrame(src);
                
                Bitmap bitmap = BitmapConverter.ToBitmap(src);
                
 
                Invalidate();
                pictureBox1.Invalidate();
 
 
                imgshow = bitmap;
                
            }
 
        }

2,在调用时开启线程，可以在主函数内调用，也可在按钮内调用

      private void button1_Click(object sender, EventArgs e)
        {
 
           // Image imgshow0 = Image.FromFile("src.jpg");
          //  pictureBox1.Image = imgshow0;
            Thread threadA = new Thread(run_cap);
            threadA.Start();
 
        }

3，在form框架调用重绘函数将每一帧重绘到pictureBox1

this.pictureBox1.Paint += PictureBox1_Paint;

4，函数如下：

       private void PictureBox1_Paint(object sender, PaintEventArgs e)
        {
           if (f)
            {
 
                           
                Invalidate();pictureBox1.Invalidate();    
                e.Graphics.DrawImage(imgshow,0,0);
 
            }
 
        }

5，运行如下：