解决WPF调用VLC播放RTSP视频流时修改AspectRatio宽高比无效的问题

WPF调用VLC的方法讲解的很多，可参考[RTSP]WPF用VLC显示RTSP视频。值得注意的是采用页面端创建VlcControl的方式，后端更改VlcVideoSourceProvider. MediaPlayer.Play的options时没有效果，如果设置VlcVideoSourceProvider.MediaPlayer.Video.AspectRatio改变宽高比也没有效果，不知道是不是更改方式有问题（成功解决的可以留言交流下）。所以就换一个加载思路：在页面端使用Image控件来展示，后端采用Image绑定VlcVideoSourceProvider.VideoSource的方式加载，只需要设置Image控件的Stretch="Fill"即可实现视频比例的缩放。

实现效果：

1、首先在工程目录下新建一个文件夹如libvlc里面放x64和x86的VLC相关插件

2、窗体

3、交互逻辑，开了4个线程去分别加载视频流，LogHelper类参考C#一个完整的Log4net使用实例

using System;
using System.IO;
using System.Reflection;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Data;
using VideoMonitoring.Utils;
using Vlc.DotNet.Wpf;

namespace VideoMonitoring
{
    /// 

    /// MainWindow.xaml 的交互逻辑
    /// 
    public partial class MainWindow : Window
    {
        private VlcVideoSourceProvider sourceProvider1;
        private VlcVideoSourceProvider sourceProvider2;
        private VlcVideoSourceProvider sourceProvider3;
        private VlcVideoSourceProvider sourceProvider4;
        private string RTSPPath = "rtsp://184.72.239.149/vod/mp4://BigBuckBunny_175k.mov";//视频地址

        public MainWindow()
        {
            InitializeComponent();
        }
        /// 

        /// 页面加载
        /// 
        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            //加载视频
            TaskFactory tf = new TaskFactory();
            Task taskTrack1 = tf.StartNew(() => LoadVideo1());
            Task taskTrack2 = tf.StartNew(() => LoadVideo2());
            Task taskTrack3 = tf.StartNew(() => LoadVideo3());
            Task taskTrack4 = tf.StartNew(() => LoadVideo4());
        }

        #region 视频加载
        private void LoadVideo1()
        {
            try
            {
                var currentAssembly = Assembly.GetEntryAssembly();
                var currentDirectory = new FileInfo(currentAssembly.Location).DirectoryName;
                var libDirectory = new DirectoryInfo(Path.Combine(currentDirectory, "libvlc", IntPtr.Size == 4 ? "x86" : "x64"));
                sourceProvider1 = new VlcVideoSourceProvider(this.Dispatcher);
                sourceProvider1.CreatePlayer(libDirectory);
                sourceProvider1.MediaPlayer.Play(new Uri(RTSPPath));//可替换为视频监控地址
                this.Video1.Dispatcher.Invoke(() => {
                    this.Video1.SetBinding(System.Windows.Controls.Image.SourceProperty,
                    new Binding(nameof(VlcVideoSourceProvider.VideoSource)) { Source = sourceProvider1 });
                });
            }
            catch (Exception ex)
            {
                LogHelper.log.Error(string.Format("加载视频1失败：{0}", ex));
            }
        }
        private void LoadVideo2()
        {
            try
            {
                var currentAssembly = Assembly.GetEntryAssembly();
                var currentDirectory = new FileInfo(currentAssembly.Location).DirectoryName;
                var libDirectory = new DirectoryInfo(Path.Combine(currentDirectory, "libvlc", IntPtr.Size == 4 ? "x86" : "x64"));
                sourceProvider2 = new VlcVideoSourceProvider(this.Dispatcher);
                sourceProvider2.CreatePlayer(libDirectory);
                sourceProvider2.MediaPlayer.Play(new Uri(RTSPPath));
                this.Video2.Dispatcher.Invoke(() => {
                    this.Video2.SetBinding(System.Windows.Controls.Image.SourceProperty,
                    new Binding(nameof(VlcVideoSourceProvider.VideoSource)) { Source = sourceProvider2 });
                });
            }
            catch (Exception ex)
            {
                LogHelper.log.Error(string.Format("加载视频2失败：{0}", ex));
            }
        }
        private void LoadVideo3()
        {
            try
            {
                var currentAssembly = Assembly.GetEntryAssembly();
                var currentDirectory = new FileInfo(currentAssembly.Location).DirectoryName;
                var libDirectory = new DirectoryInfo(Path.Combine(currentDirectory, "libvlc", IntPtr.Size == 4 ? "x86" : "x64"));
                sourceProvider3 = new VlcVideoSourceProvider(this.Dispatcher);
                sourceProvider3.CreatePlayer(libDirectory);
                sourceProvider3.MediaPlayer.Play(new Uri(RTSPPath));
                this.Video3.Dispatcher.Invoke(() => {
                    this.Video3.SetBinding(System.Windows.Controls.Image.SourceProperty,
                    new Binding(nameof(VlcVideoSourceProvider.VideoSource)) { Source = sourceProvider3 });
                });
            }
            catch (Exception ex)
            {
                LogHelper.log.Error(string.Format("加载视频3失败：{0}", ex));
            }
        }
        private void LoadVideo4()
        {
            try
            {
                var currentAssembly = Assembly.GetEntryAssembly();
                var currentDirectory = new FileInfo(currentAssembly.Location).DirectoryName;
                var libDirectory = new DirectoryInfo(Path.Combine(currentDirectory, "libvlc", IntPtr.Size == 4 ? "x86" : "x64"));
                sourceProvider4 = new VlcVideoSourceProvider(this.Dispatcher);
                sourceProvider4.CreatePlayer(libDirectory);
                sourceProvider4.MediaPlayer.Play(new Uri(RTSPPath));
                this.Video4.Dispatcher.Invoke(() => {
                    this.Video4.SetBinding(System.Windows.Controls.Image.SourceProperty,
                    new Binding(nameof(VlcVideoSourceProvider.VideoSource)) { Source = sourceProvider4 });
                });
            }
            catch (Exception ex)
            {
                LogHelper.log.Error(string.Format("加载视频4失败：{0}", ex));
            }
        }
        #endregion

        private void Window_Closed(object sender, EventArgs e)
        {
            if (sourceProvider1 != null)
            {
                sourceProvider1.Dispose();
            }
            if (sourceProvider2 != null)
            {
                sourceProvider2.Dispose();
            }
            if (sourceProvider3 != null)
            {
                sourceProvider3.Dispose();
            }
            if (sourceProvider4 != null)
            {
                sourceProvider4.Dispose();
            }
        }
    }
}