title: Blurred Decoration Image in Flutter
body: <p>I have the background of my app set like so:</p>
  
  <pre><code>class MyApp extends StatelessWidget {
    @override
    Widget build(BuildContext context) {
      return new MaterialApp(
        home: new Container(
          decoration: new BoxDecoration(
            image: new DecorationImage(
              image: new ExactAssetImage('assets/lol/aatrox.jpg'),
              fit: BoxFit.cover,
            ),
          ),
          child: new BackdropFilter(filter: new ImageFilter.blur(sigmaX: 600.0, sigmaY: 1000.0)),
          width: 400.0,
        ),
      );
    }
  }
  </code></pre>
  
  <p>I'm wanting to blur the <code>DecorationImage</code>, so I added a <code>BackdropFilter</code> to the Container, but I don't see any change. What am I doing wrong?</p>