UWP媒体捕获不通过网络摄像头录制视频

Question

我想开发一个UWP应用程序，我需要通过网络摄像头录制视频。我在这里遵循微软教程，但问题是我一次又一次地跟随错误，并且记录不起作用。

错误

“这对象需要所请求的操作 可以进行之前被初始化。\ r \ n该对象需要之前 请求的操作可以被执行以进行初始化。”

这里是我的代码：

int counter = 1; 
       var myVideos = await Windows.Storage.StorageLibrary.GetLibraryAsync(Windows.Storage.KnownLibraryId.Videos); 
       StorageFile file = await myVideos.SaveFolder.CreateFileAsync("survillance "+DateTime.Now.ToString("dd-MM-yyyy")+"_"+counter+".wmv", CreationCollisionOption.GenerateUniqueName); 

       try 
       { 
        MediaEncodingProfile recordProfile = null; 
        recordProfile = MediaEncodingProfile.CreateWmv(VideoEncodingQuality.Auto); 

        _mediaRecording = await _mediaCapture.PrepareLowLagRecordToStorageFileAsync(recordProfile,file); 
        await _mediaRecording.StartAsync(); 


        status.Text = "Video recording in progress..."; 


       } 
       catch (Exception ex) 
       { 

        status.Text = "Failed to Capture..."; 
        var msg = new MessageDialog(ex.Message, "Capturing Error").ShowAsync(); 
       } 

请帮我找出这个问题。谢谢

Answer 1

你开始捕获之前忘了打电话MediaCapture.InitializeAsync()。

MediaEncodingProfile recordProfile = MediaEncodingProfile.CreateMp4(VideoEncodingQuality.Auto); 

_mediaCapture = new MediaCapture(); 
_mediaCapture.InitializeAsync(); 

_mediaRecording = await _mediaCapture.PrepareLowLagRecordToStorageFileAsync(recordProfile,file); 
await _mediaRecording.StartAsync();