emgu 4.1.1.3497 capture video by a webcam.

ref: https://github.com/emgucv/emgucv/tree/master/Emgu.CV.Example/CameraCapture

Visual Studio 2017 @ Windows 10 x64 @ ASUS  x450J

1. Form Application
1-1. New project by Form Template.
1-2. nuget Add emgu 4.1.1.3497
1-3. Toolbox add Emgu.CV ImageBox (imageBox1)
1-4. Form1.cs
add System.ServiceModel 4.0
namespace wk12webcam
{
    // nuget add emgu.cv
    // ref add System.ServiceModel 4.0
    using Emgu.CV;
    using Emgu.CV.CvEnum;
    using Emgu.CV.Structure;
    using Emgu.Util;

    public partial class Form1 : Form
    {
        private VideoCapture _capture = null;
        private Mat _frame;
        public Form1()
        {
            InitializeComponent();
            this.FormClosing += Form1_FormClosing;
            _capture = new VideoCapture();
            _capture.ImageGrabbed += _capture_ImageGrabbed;
            _frame = new Mat();
            _capture.Start();
        }

        private void Form1_FormClosing(object sender, FormClosingEventArgs e)
        {
            _capture.Dispose();
        }

        private void _capture_ImageGrabbed(object sender, EventArgs e)
        {
            if (_capture != null && _capture.Ptr != IntPtr.Zero)
            {
                _capture.Retrieve(_frame, 0);
                imageBox1.Image = _frame;
            }
        }
    }
}

1-5. Results:

2. WPF

2-1. New project by WPF Template.
2-2. nuget Add emgu 4.1.1.3497
2-3. MainWindow.xaml
 <Grid>
        <Image Name="imageBox1"/>
 </Grid>
2-4. MainWindow.xaml.ccs
Similar procedure causes error as follows

ref: http://csjoublog.blogspot.com/2018/12/emgu-webcam-capture-wpf.html
namespace wk12WPFWebcam
{
    // Add System.ServiceModel 4.0
    using Emgu.CV;
    using Emgu.CV.CvEnum;
    using Emgu.CV.Structure;
    using Emgu.Util;
    using System.Drawing;
    using System.IO;
    using System.Threading;
    using System.Runtime.InteropServices;
    using System.Windows.Interop;

    /// <summary>
    /// MainWindow.xaml 的互動邏輯
    /// </summary>
    public partial class MainWindow : Window
    {
        private VideoCapture _capture = null;
        private Mat _frame;
        public MainWindow()
        {
            InitializeComponent();
            this.Closing += MainWindow_Closing;
            _capture = new VideoCapture();
            //_capture.ImageGrabbed += _capture_ImageGrabbed;
            _frame = new Mat();
            //_capture.Start();
            ComponentDispatcher.ThreadIdle += ComponentDispatcher_ThreadIdle;
        }

        private void ComponentDispatcher_ThreadIdle(object sender, EventArgs e)
        {
            using (var imageFrame = _capture.QueryFrame().ToImage<Bgr, Byte>())
            {
                if (imageFrame != null)
                {
                    imageBox1.Source = ConvertBitmapToImageSource(imageFrame.Bitmap);
                }
            }
        }
        private void MainWindow_Closing(object sender, System.ComponentModel.CancelEventArgs e)
        {
            _capture.Dispose();
        }
        private ImageSource ConvertBitmapToImageSource(Bitmap imToConvert)
        {
            Bitmap bmp = new Bitmap(imToConvert);
            MemoryStream ms = new MemoryStream();
            bmp.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp);
            BitmapImage image = new BitmapImage();
            image.BeginInit();
            ms.Seek(0, SeekOrigin.Begin);
            image.StreamSource = ms;
            image.EndInit();
            ImageSource sc = (ImageSource)image;
            return sc;
        }
    }
}