private async Task StartVideoDeviceAsync()
{
try
{
if (mediaCapture == null || mediaCapture.CameraStreamState == CameraStreamState.Shutdown || mediaCapture.CameraStreamState == CameraStreamState.NotStreaming)
{
mediaCapture?.Dispose();
var selectedCamera = await CameraUtilities.FindBestCameraAsync(DeviceClass.VideoCapture);
if (selectedCamera == null)
{
await new MessageDialog("There are no cameras connected, please connect a camera and try again.").ShowAsync();
mediaCapture?.Dispose();
mediaCapture = null;
return;
}
mediaCapture = new MediaCapture();
// put reference in App so that it can be disposed if app is suspended
App.MediaCaptureManager = mediaCapture;
await mediaCapture.InitializeAsync(new MediaCaptureInitializationSettings { VideoDeviceId = selectedCamera.Id });
WebCamCaptureElement.Source = mediaCapture;
}
if (mediaCapture.CameraStreamState == CameraStreamState.NotStreaming)
{
// Frame lock timer logic credit: Rene Shulte, see https://github.com/sevans4067/WinMl-TinyYOLO/blob/master/TinyYOLO/MainPage.xaml.cs
if (frameProcessingTimer != null)
{
frameProcessingTimer.Cancel();
frameProcessingSemaphore.Release();
}
frameProcessingTimer = ThreadPoolTimer.CreatePeriodicTimer(ProcessCurrentVideoFrame, TimeSpan.FromMilliseconds(66)); // 1000 (ms) / 15 (fps) == 66 (ms)
videoProperties = mediaCapture.VideoDeviceController.GetMediaStreamProperties(MediaStreamType.VideoPreview) as VideoEncodingProperties;
await mediaCapture.StartPreviewAsync();
App.GlobalDisplayRequest.RequestActive();
WebCamCaptureElement.Visibility = Visibility.Visible;
}
}
catch (Exception ex)
{
await Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => StatusBlock.Text = $"StartVideoDeviceAsync Error: {ex.Message}");
}
}
private async Task InitializeVideoAsync()
{
ReloadVideoStreamButton.Visibility = Visibility.Collapsed;
ShowBusyIndicator("Initializing...");
try
{
currentState = RecordingState.NotInitialized;
PreviewMediaElement.Source = null;
ShowBusyIndicator("starting video device...");
mediaCapture = new MediaCapture();
// put reference in App so that it can be disposed if app is suspended
App.MediaCaptureManager = mediaCapture;
selectedCamera = await CameraUtilities.FindBestCameraAsync();
if (selectedCamera == null)
{
await new MessageDialog("There are no cameras connected, please connect a camera and try again.").ShowAsync();
await DisposeMediaCaptureAsync();
HideBusyIndicator();
return;
}
await mediaCapture.InitializeAsync(new MediaCaptureInitializationSettings { VideoDeviceId = selectedCamera.Id });
if (mediaCapture.MediaCaptureSettings.VideoDeviceId != "" && mediaCapture.MediaCaptureSettings.AudioDeviceId != "")
{
ShowBusyIndicator("camera initialized..");
mediaCapture.Failed += Failed;
}
else
{
ShowBusyIndicator("camera error!");
}
//------starting preview----------//
ShowBusyIndicator("starting preview...");
PreviewMediaElement.Source = mediaCapture;
await mediaCapture.StartPreviewAsync();
currentState = RecordingState.Previewing;
}
catch (UnauthorizedAccessException ex)
{
Debug.WriteLine($"InitializeVideo UnauthorizedAccessException\r\n {ex}");
ShowBusyIndicator("Unauthorized Access Error");
await new MessageDialog("-----Unauthorized Access Error!-----\r\n\n" +
"This can happen for a couple reasons:\r\n" +
"-You have disabled Camera access to the app\r\n" +
"-You have disabled Microphone access to the app\r\n\n" +
"To fix this, go to Settings > Privacy > Camera (or Microphone) and reenable it.").ShowAsync();
await DisposeMediaCaptureAsync();
}
catch (Exception ex)
{
ShowBusyIndicator("Initialize Video Error");
await new MessageDialog("InitializeVideoAsync() Exception\r\n\nError Message: " + ex.Message).ShowAsync();
currentState = RecordingState.NotInitialized;
PreviewMediaElement.Source = null;
}
finally
{
HideBusyIndicator();
}
}