<Canvas x:Name="imageCanvas" Visibility="Collapsed" ><Path x:Name="nonselectRegion" Fill="#88FFFFFF"  ><Path.Data><GeometryGroup><RectangleGeometry Rect="{Binding OuterRect}"></RectangleGeometry><RectangleGeometry Rect="{Binding SelectedRect}"></RectangleGeometry></GeometryGroup></Path.Data></Path><Path x:Name="selectRegion" Fill="Transparent" Stroke="{ThemeResource ApplicationForegroundThemeBrush}" StrokeThickness="1"><Path.Data><RectangleGeometry Rect="{Binding SelectedRect}"/></Path.Data></Path><Rectangle x:Name="horizontalLine" Canvas.Left="{Binding SelectedRect.Left}" Canvas.Top="{Binding HorizontalLineCanvasTop}" Height="1" Width="{Binding SelectedRect.Width}" Fill="{ThemeResource ApplicationForegroundThemeBrush}"/><Rectangle x:Name="verticalLine" Canvas.Left="{Binding VerticalLineCanvasLeft}" Canvas.Top="{Binding SelectedRect.Top}" Width="1" Height="{Binding SelectedRect.Height}" Fill="{ThemeResource ApplicationForegroundThemeBrush}"/><Rectangle x:Name="horizontalLine1" Canvas.Left="{Binding SelectedRect.Left}" Canvas.Top="{Binding HorizontalLine1CanvasTop}" Height="1" Width="{Binding SelectedRect.Width}" Fill="{ThemeResource ApplicationForegroundThemeBrush}"/><Rectangle x:Name="verticalLine1" Canvas.Left="{Binding VerticalLine1CanvasLeft}" Canvas.Top="{Binding SelectedRect.Top}" Width="1" Height="{Binding SelectedRect.Height}" Fill="{ThemeResource ApplicationForegroundThemeBrush}"/><Ellipse x:Name="topLeftThumb"  Canvas.Left="{Binding SelectedRect.Left}" Canvas.Top="{Binding SelectedRect.Top}"/><Ellipse x:Name="topRightThumb"  Canvas.Left="{Binding SelectedRect.Right}" Canvas.Top="{Binding SelectedRect.Top}"/><Ellipse x:Name="bottomLeftThumb"  Canvas.Left="{Binding SelectedRect.Left}" Canvas.Top="{Binding SelectedRect.Bottom}"/><Ellipse x:Name="bottomRightThumb"  Canvas.Left="{Binding SelectedRect.Right}" Canvas.Top="{Binding SelectedRect.Bottom}"/></Canvas>

 async static private Task<byte[]> GetPixelData(BitmapDecoder decoder, uint startPointX, uint startPointY,uint width, uint height, uint scaledWidth, uint scaledHeight){BitmapTransform transform = new BitmapTransform();BitmapBounds bounds = new BitmapBounds();bounds.X = startPointX;bounds.Y = startPointY;bounds.Height = height;bounds.Width = width;transform.Bounds = bounds;transform.ScaledWidth = scaledWidth;transform.ScaledHeight = scaledHeight;// Get the cropped pixels within the bounds of transform.PixelDataProvider pix = await decoder.GetPixelDataAsync(BitmapPixelFormat.Bgra8,BitmapAlphaMode.Straight,transform,ExifOrientationMode.IgnoreExifOrientation,ColorManagementMode.ColorManageToSRgb);byte[] pixels = pix.DetachPixelData();return pixels;}