void barcodeReader_SampleDecoded(VideoBarcodeReader sender, SampleDecodedEventArgs e)
{
var ignore = Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () =>
{
if (e.Text == null)
{
BarcodeOutline.Points.Clear();
TextLog.Text = "No barcode";
}
else
{
TextLog.Text = e.Text;
BarcodeOutline.Points.Clear();
foreach (var point in e.Points)
{
BarcodeOutline.Points.Add(new Point(point.X * BarcodeOutline.Width, point.Y * BarcodeOutline.Height));
}
}
});
}
private async Task InitializeCaptureAsync()
{
var settings = new MediaCaptureInitializationSettings
{
StreamingCaptureMode = StreamingCaptureMode.Video
};
await settings.SelectVideoDeviceAsync(VideoDeviceSelection.BackOrFirst);
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 SwapChainPanel 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
};
var reader = await MediaReader.CreateFromMediaCaptureAsync(capture, AudioInitialization.Deselected, VideoInitialization.Bgra8);
var presenter = ImagePresenter.CreateFromSwapChainPanel(Preview, reader.GraphicsDevice, (int)format.Width, (int)format.Height);
m_capture = capture;
// Run preview/detection out of UI thread
var ignore = Task.Run(async() =>
{
using (var barcodeReader = new VideoBarcodeReader())
{
barcodeReader.SampleDecoded += barcodeReader_SampleDecoded;
while (true)
{
Logger.Events.VideoStream_ReadStart();
using (var result = await reader.VideoStream.ReadAsync())
{
Logger.Events.VideoStream_ReadStop();
if (result.Error)
{
break;
}
var sample = (MediaSample2D)result.Sample;
if (sample == null)
{
continue;
}
presenter.Present(sample);
barcodeReader.QueueSample(sample);
result.DetachSample(); // Sample ownership transferred to barcodeReader
}
}
barcodeReader.SampleDecoded -= barcodeReader_SampleDecoded;
reader.Dispose();
presenter.Dispose();
}
});
}
