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我们设法使用 UWP 创建了一个可用的 Miracast 接收器，我们希望在 .NET Core 应用程序中使用此功能。因此，我们按照本指南在 .NET Core 项目中使用 UWP api：

将 UWP api 与 WPF 和 .NET Core 结合使用

项目运行，我们获得了从智能手机到应用程序的连接，但是我们没有收到来自 MediaPlayer 对象的任何视频帧（与正常工作的原始 UWP 项目不同）

我们观察到在 MediaSource 对象中我们获得了一个 mcrecv url (Example -> mcrecv://192.168.137.247:7236/h-0000000c/192.168.137.1)

但随后使用它的 MediaPlayer 不会触发任何 VideoFrameAvailable 事件。

我们如何解决这个问题？以下是我们使用的基本实现：

using System;
using System.Diagnostics;
using System.Windows;
using Windows.Graphics.Imaging;
using Windows.Media.Miracast;
using Windows.Media.Playback;

namespace Miracast_GUI
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MiracastReceiver receiver;
        public MiracastReceiverSession session;
        public MediaPlayer mp;
        public SoftwareBitmap frameServerDest;
        public MiracastReceiverConnection connection;

        public MainWindow()
        {
            InitializeComponent();
            // Starts service
            StartMiracastService();
        }

        public void StartMiracastService()
        {
            receiver = new MiracastReceiver();
            receiver.StatusChanged += Receiver_StatusChanged;
            MiracastReceiverSettings settings = receiver.GetDefaultSettings();

            settings.FriendlyName = "Miracast-Service-Test";
            settings.AuthorizationMethod = MiracastReceiverAuthorizationMethod.None;
            settings.ModelName = receiver.GetDefaultSettings().ModelName;
            settings.ModelNumber = receiver.GetDefaultSettings().ModelNumber;
            settings.RequireAuthorizationFromKnownTransmitters = receiver.GetDefaultSettings().RequireAuthorizationFromKnownTransmitters;

            receiver.DisconnectAllAndApplySettings(settings);

            session = receiver.CreateSession(/*CoreApplication.MainView*/ null);
            session.AllowConnectionTakeover = true;

            session.ConnectionCreated += Session_ConnectionCreated;
            session.MediaSourceCreated += Session_MediaSourceCreated;
            session.Disconnected += Session_Disconnected;

            MiracastReceiverSessionStartResult result = session.Start();
            Debug.WriteLine("Status: " + result.Status);
        }

        private void Session_Disconnected(MiracastReceiverSession sender, MiracastReceiverDisconnectedEventArgs args)
        {
            session.Dispose();
        }

        private void Receiver_StatusChanged(MiracastReceiver sender, object args)
        {
            Debug.WriteLine(receiver.GetStatus().ListeningStatus);
        }

        private void Session_ConnectionCreated(MiracastReceiverSession sender, MiracastReceiverConnectionCreatedEventArgs args)
        {
            connection = args.Connection;
            connection.InputDevices.Keyboard.TransmitInput = true;
            connection.InputDevices.GameController.Mode =
                MiracastReceiverGameControllerDeviceUsageMode.AsMouseAndKeyboard;

            Debug.WriteLine("CONNECTION CREATED");
        }

        private void Session_MediaSourceCreated(MiracastReceiverSession sender, MiracastReceiverMediaSourceCreatedEventArgs args)
        {
            mp = new MediaPlayer
            {
                IsVideoFrameServerEnabled = true,
                AutoPlay = true,
                Source = args.MediaSource,
                RealTimePlayback = true
            };

            mp.VideoFrameAvailable += Mp_VideoFrameAvailable;
            Debug.WriteLine(mp.PlaybackSession.PlaybackState);
            mp.Play();

            Debug.WriteLine("MEDIA SOURCE CREATED");
        }

        private void Mp_VideoFrameAvailable(MediaPlayer sender, object args)
        {
            Console.WriteLine("Received frame...");
        }
    }
}
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1 回答 1

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如果未使用“Internet（客户端和服务器）”功能，UWP 应用的 MediaPlayer 不会触发 VideoFrameAvailable 事件。也许 WPF 项目没有任何能力？因此，wpf 应用程序无法使用其他需要此功能的服务。我不知道如何在 wpf 中使用 uwp 功能。

于 2020-09-02T12:58:33.230 回答