title: Blur the background of the WPF container
body: <p>Ultimately, what I want to achieve is a replication to some extend, of an Aero glass functionality of a WPF content control.</p>
  
  <p>If I apply the <code>BlurEffect</code> to a <code>StackPanel</code> that contains a <code>TextBlock</code>, I will have the <code>TextBlock</code>'s text blurred.</p>
  
  <p>Consider an examples: </p>
  
  <p>No blur</p>
  
  <p><img src="https://i.stack.imgur.com/U4dNi.png" alt="no blur"></p>
  
  <p>and with <code>&lt;BlurEffect Radius="5" KernelType="Gaussian"/&gt;</code></p>
  
  <p><img src="https://i.stack.imgur.com/mOCCt.png" alt="with blur"></p>
  
  <p>But is there a WPF way to blur the background behind the panel, and not it's contents? </p>
  
  <p>The background of the <code>StackPanel</code> is a desktop, and the window that hosts it is set to <code>AllowTransparency="True"</code> to allow the custom-shaped look. </p>