protected override async void OnNavigatedTo(NavigationEventArgs e)
{
DisplayInformation.AutoRotationPreferences = DisplayOrientations.Landscape;
//
// Doing all that video processing is too much for low-end phones like the Lumia 520
// Pick-and-choose which piece should run
//
VideoPreview.MediaFailed += VideoPreview_MediaFailed;
//var file = await StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appx:///Assets/video.cvmpilj.mjpg"));
//var stream = await file.OpenAsync(FileAccessMode.Read);
//var source = await HttpMjpegCaptureSource.CreateFromStreamAsync(stream, "myboundary");
var source = await HttpMjpegCaptureSource.CreateFromUriAsync("http://216.123.238.208/axis-cgi/mjpg/video.cgi?camera&resolution=640x480");
VideoPreview.SetMediaStreamSource(source.Source);
var settings = new MediaCaptureInitializationSettings
{
StreamingCaptureMode = StreamingCaptureMode.Video
};
await settings.SelectVideoDeviceAsync(VideoDeviceSelection.BackOrFirst);
_capture = new MediaCapture();
await _capture.InitializeAsync(settings);
var graphicsDevice = MediaGraphicsDevice.CreateFromMediaCapture(_capture);
var previewProps = (VideoEncodingProperties)_capture.VideoDeviceController.GetMediaStreamProperties(MediaStreamType.VideoPreview);
TextLog.Text += String.Format("Preview: {0} {1}x{2} {3}fps\n", previewProps.Subtype, previewProps.Width, previewProps.Height, previewProps.FrameRate.Numerator / (float)previewProps.FrameRate.Denominator);
TextLog.Text += "Creating MediaSamplePresenter from SurfaceImageSource\n";
var image = new SurfaceImageSource((int)previewProps.Width, (int)previewProps.Height);
ImagePreview.Source = image;
_imagePresenter = ImagePresenter.CreateFromSurfaceImageSource(image, graphicsDevice, (int)previewProps.Width, (int)previewProps.Height);
TextLog.Text += "Creating MediaSamplePresenter from SwapChainPanel\n";
_swapChainPresenter = ImagePresenter.CreateFromSwapChainPanel(
SwapChainPreview,
graphicsDevice,
(int)previewProps.Width,
(int)previewProps.Height
);
TextLog.Text += "Creating MediaReader\n";
_mediaReader = await MediaReader.CreateFromMediaCaptureAsync(_capture, AudioInitialization.Deselected, VideoInitialization.Bgra8);
TextLog.Text += "Starting video loop\n";
var ignore = Task.Run(() => VideoLoop());
}
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();
}
});
}