Xaml for full screen camera view

CameraView.xaml

<Grid x:Name="LayoutRoot" VerticalAlignment="Stretch">
   <Canvas x:Name="viewfinderCanvas">
      <Canvas.Background>
         <VideoBrush x:Name="viewfinderBrush">
            <VideoBrush.RelativeTransform>
               <CompositeTransform x:Name="previewTransform" CenterX=".5" CenterY=".5" />
            </VideoBrush.RelativeTransform>
         </VideoBrush>
      </Canvas.Background>
   </Canvas>
</Grid>