解决UWP前台摄像头显示问题左右翻转问题的一个解决办法

摄像头得到的图像是左右相反的，为了得到和照镜子一样的体验，使用Xaml的3DProjection功能额将显示元素180度旋转即可，这是解决前台摄像头显示问题左右翻转问题的一个解决办法

       <MediaPlayerElement Grid.Column="0" Name="UIMediaPlayerElement" Stretch="Uniform" AreTransportControlsEnabled="False" Canvas.ZIndex="-1" MaxWidth="720" MaxHeight="720" RenderTransformOrigin="0.5,0.5">

           <MediaPlayerElement.Projection>

               <PlaneProjection RotationX="180" />

           </MediaPlayerElement.Projection>

           <MediaPlayerElement.RenderTransform>

               <TransformGroup>

                   <ScaleTransform ScaleX="-1" ScaleY="-1" />

                   <SkewTransform />

                   <RotateTransform />

                   <TranslateTransform />

               </TransformGroup>

           </MediaPlayerElement.RenderTransform>

       </MediaPlayerElement>