// Must be called on the UI thread
private async Task DisposeCaptureAsync()
{
Preview.Source = null;
if (m_autoFocus != null)
{
m_autoFocus.Dispose();
m_autoFocus = null;
}
MediaCapture capture;
lock (this)
{
capture = m_capture;
m_capture = null;
}
if (capture != null)
{
capture.Failed -= capture_Failed;
await capture.StopPreviewAsync();
capture.Dispose();
}
}
// Must be called on the UI thread
private async Task InitializeCaptureAsync()
{
if (m_initializing || (m_capture != null))
{
return;
}
m_initializing = true;
try
{
var settings = new MediaCaptureInitializationSettings
{
VideoDeviceId = await GetBackOrDefaulCameraIdAsync(),
StreamingCaptureMode = StreamingCaptureMode.Video
};
var capture = new MediaCapture();
await capture.InitializeAsync(settings);
// Select the capture resolution closest to screen resolution
var formats = capture.VideoDeviceController.GetAvailableMediaStreamProperties(MediaStreamType.VideoPreview);
var format = (VideoEncodingProperties)formats.OrderBy((item) =>
{
var props = (VideoEncodingProperties)item;
return(Math.Abs(props.Width - this.ActualWidth) + Math.Abs(props.Height - this.ActualHeight));
}).First();
await capture.VideoDeviceController.SetMediaStreamPropertiesAsync(MediaStreamType.VideoPreview, format);
// Make the preview full screen
var scale = Math.Min(this.ActualWidth / format.Width, this.ActualHeight / format.Height);
Preview.Width = format.Width;
Preview.Height = format.Height;
Preview.RenderTransformOrigin = new Point(.5, .5);
Preview.RenderTransform = new ScaleTransform {
ScaleX = scale, ScaleY = scale
};
//BarcodeOutline.Width = format.Width;
//BarcodeOutline.Height = format.Height;
//BarcodeOutline.RenderTransformOrigin = new Point(.5, .5);
//BarcodeOutline.RenderTransform = new ScaleTransform { ScaleX = scale, ScaleY = scale };
// Enable QR code detection
var definition = new LumiaAnalyzerDefinition(ColorMode.Yuv420Sp, 640, AnalyzeBitmap);
await capture.AddEffectAsync(MediaStreamType.VideoPreview, definition.ActivatableClassId, definition.Properties);
// Start preview
//m_time.Restart();
Preview.Source = capture;
await capture.StartPreviewAsync();
capture.Failed += capture_Failed;
m_autoFocus = await ContinuousAutoFocus.StartAsync(capture.VideoDeviceController.FocusControl);
m_capture = capture;
}
catch (Exception e)
{
MessageDialog dialog = new MessageDialog(string.Format("Failed to start the camera: {0}", e.Message));
await dialog.ShowAsync();
}
m_initializing = false;
}
public static async Task <ContinuousAutoFocus> StartAsync(FocusControl control)
{
var autoFocus = new ContinuousAutoFocus(control);
#if WINDOWS_PHONE_APP
AutoFocusRange range;
if (control.SupportedFocusRanges.Contains(AutoFocusRange.FullRange))
{
range = AutoFocusRange.FullRange;
}
else if (control.SupportedFocusRanges.Contains(AutoFocusRange.Normal))
{
range = AutoFocusRange.Normal;
}
else
{
// Auto-focus disabled
return(autoFocus);
}
FocusMode mode;
if (control.SupportedFocusModes.Contains(FocusMode.Continuous))
{
mode = FocusMode.Continuous;
}
else if (control.SupportedFocusModes.Contains(FocusMode.Single))
{
mode = FocusMode.Single;
}
else
{
// Auto-focus disabled
return(autoFocus);
}
if (mode == FocusMode.Continuous)
{
// True continuous auto-focus
var settings = new FocusSettings()
{
AutoFocusRange = range,
Mode = mode,
WaitForFocus = false,
DisableDriverFallback = false
};
control.Configure(settings);
await control.FocusAsync();
}
else
{
// Simulated continuous auto-focus
var settings = new FocusSettings()
{
AutoFocusRange = range,
Mode = mode,
WaitForFocus = true,
DisableDriverFallback = false
};
control.Configure(settings);
var ignore = Task.Run(async() => { await autoFocus.DriveAutoFocusAsync(); });
}
#else
if (control.SupportedPresets.Contains(FocusPreset.Auto))
{
await control.SetPresetAsync(FocusPreset.Auto, /*completeBeforeFocus*/ true);
}
#endif
return(autoFocus);
}
