private async Task InitiateCameraCaptureObject(Panel deviceLocation)
{
try
{
if (_bInitializingCamera || _cameraCapture != null) return;
_bInitializingCamera = true;
await InitCaptureSettings(deviceLocation);
_cameraCapture = new MediaCapture();
await _cameraCapture.InitializeAsync(_captureInitSettings);
//Enable QR Detector
if (_qrDetectionModeEnabled)
{
var formats = _cameraCapture.VideoDeviceController.GetAvailableMediaStreamProperties(MediaStreamType.Photo);
var format = (VideoEncodingProperties)formats.OrderBy((item) =>
{
var props = (VideoEncodingProperties)item;
return Math.Abs(props.Height - ActualWidth) + Math.Abs(props.Width - ActualHeight);
}).First();
await _cameraCapture.VideoDeviceController.SetMediaStreamPropertiesAsync(MediaStreamType.Photo, format);
var definition = new LumiaAnalyzerDefinition(ColorMode.Yuv420Sp, format.Width >= format.Height ? format.Width : format.Height, AnalyzeImage);
await _cameraCapture.AddEffectAsync(MediaStreamType.VideoPreview, definition.ActivatableClassId, definition.Properties);
_barcodeReader = _barcodeReader ?? new BarcodeReader
{
Options = new DecodingOptions
{
PossibleFormats = new[] { BarcodeFormat.QR_CODE, BarcodeFormat.CODE_128 },
TryHarder = true
}
};
}
PhotoPreview.Source = _cameraCapture;
await _cameraCapture.StartPreviewAsync();
_cameraCapture.Failed += CameraCaptureOnFailed;
_scannerAutoFocus = await ScannerAutoFocus.StartAsync(_cameraCapture.VideoDeviceController.FocusControl);
_cameraCapture.SetPreviewRotation(VideoRotation.Clockwise90Degrees);
}
catch (Exception ex)
{
WindowsPhoneUtils.Log(ex.Message);
}
_bInitializingCamera = false;
}
private async Task DisposeCaptureAsync()
{
_cameraCapture.Failed -= CameraCaptureOnFailed;
await _cameraCapture.ClearEffectsAsync(MediaStreamType.VideoPreview);
PhotoPreview.Source = null;
_barcodeReader = null;
if (_scannerAutoFocus != null)
{
_scannerAutoFocus.Dispose();
_scannerAutoFocus = null;
}
MediaCapture capture;
lock (this)
{
capture = _cameraCapture;
_cameraCapture = null;
}
if (capture != null)
{
capture.Failed -= CameraCaptureOnFailed;
capture.Dispose();
}
}
public static async Task<ScannerAutoFocus> StartAsync(FocusControl control)
{
var autoFocus = new ScannerAutoFocus(control);
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(); });
}
return autoFocus;
}
