[WPF] WPF Webcam & Video player with OpenCVSharp4

MainWindow.xaml

<Window x:Class="WebcamCaptureApp.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WebcamCaptureApp"
        mc:Ignorable="d"
        Title="MainWindow" Height="900" Width="1600">
    <Grid>
        <StackPanel Orientation="Vertical">
            <Image Name="imgViewport" Width="1280" Height="720"/>
            <StackPanel Orientation="Horizontal" HorizontalAlignment="Center">
                <Button Name="btPlay" Click="btPlay_Click" Content="Play" Width="100" Height="50" Margin="16"/>
                <Button Name="btStop" Click="btStop_Click" Content="Stop" Width="100" Height="50" Margin="16"/>
            </StackPanel>
        </StackPanel>
    </Grid>
</Window>

MainWindow.xaml.cs

using System;
using System.Drawing;
using System.IO;
using System.Threading;
using System.Windows;
using System.Windows.Media.Imaging;
using System.Windows.Threading;

using OpenCvSharp;
using OpenCvSharp.Extensions;

namespace WebcamCaptureApp
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : System.Windows.Window
    {
        private VideoCapture capVideo;
        private VideoCapture capCamera;
        //private const int cameraWidth = 1920;
        //private const int cameraHeight = 1080;
        int sleepTime;
        //private Bitmap wb = new Bitmap(videoWidth, videoHeight);
        Mat matImage = new Mat();

        public MainWindow()
        {
            InitializeComponent();
            InitializeVideo();
            InitializeCamera();
        }

        private void InitializeCamera()
        {
            capCamera = new VideoCapture(0);
        }

        private void InitializeVideo()
        {
            string filePath = @"D:\temp\200323.mp4";
            capVideo = new VideoCapture(filePath);
            sleepTime = (int)Math.Round(1000 / capVideo.Fps);
        }

        private void btPlay_Click(object sender, RoutedEventArgs e)
        {
            btPlay.IsEnabled = false;

            //BackgroundWorker bw = new BackgroundWorker();
            //bw.DoWork += (object sender, DoWorkEventArgs e) =>
            //{
            //    PlayVideo();
            //};
            //bw.RunWorkerAsync();

            //new Thread(PlayVideo).Start();
            new Thread(PlayCamera).Start();
        }

        private void PlayCamera()
        {
            while (!capCamera.IsDisposed)
            {
                capCamera.Read(matImage); // same as cvQueryFrame
                if (matImage.Empty()) break;
                //Thread.Sleep(sleepTime);
                Dispatcher.BeginInvoke(DispatcherPriority.Normal, new Action(() =>
                {
                    var converted = Convert(BitmapConverter.ToBitmap(matImage));
                    imgViewport.Source = converted;
                }));
            }
        }

        private void PlayVideo()
        {
            while (!capVideo.IsDisposed)
            {
                capVideo.Read(matImage); // same as cvQueryFrame
                if (matImage.Empty())
                    break;
                //BitmapConverter.ToBitmap(frame, wb);
                Thread.Sleep(sleepTime);

                Dispatcher.BeginInvoke(DispatcherPriority.Normal, new Action(() =>
                {
                    var converted = Convert(BitmapConverter.ToBitmap(matImage));
                    imgViewport.Source = converted;
                }));
            }
        }

        private void btStop_Click(object sender, RoutedEventArgs e)
        {
            if (capVideo.IsOpened())
            {
                capVideo.Dispose();
            }
            if (capCamera.IsOpened())
            {
                capCamera.Dispose();
            }
            btStop.IsEnabled = false;
        }

        public BitmapImage Convert(Bitmap src)
        {
            MemoryStream ms = new MemoryStream();
            ((System.Drawing.Bitmap)src).Save(ms, System.Drawing.Imaging.ImageFormat.Bmp);
            BitmapImage image = new BitmapImage();
            image.BeginInit();
            ms.Seek(0, SeekOrigin.Begin);
            image.StreamSource = ms;
            image.EndInit();
            return image;
        }
    }
}