UWP媒體捕獲不通過網絡攝像頭錄製視頻

Question

我想開發一個UWP應用程序，我需要通過網絡攝像頭錄製視頻。我在這裏遵循微軟教程，但問題是我一次又一次地跟隨錯誤，並且記錄不起作用。

錯誤

「這對象需要所請求的操作 可以進行之前被初始化。\ r \ n該對象需要之前 請求的操作可以被執行以進行初始化。」

這裏是我的代碼：

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(); 
       } 

請幫我找出這個問題。謝謝

Answer 1

你開始捕獲之前忘了打電話MediaCapture.InitializeAsync()。

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

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

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