    <!--
                Copyright: Copyright 1998-2001 W3C (MIT, INRIA, Keio), All Rights Reserved.
    See http://www.w3.org/Consortium/Legal/.
    Author: Warner ten Kate (warner.ten.kate@philips.com), modified by Erik Hodge, RealNetworks
               Version: Mar 26, 2001, v2
                Module: SMIL Structure Module
               Feature: profiling: systemRequired on <smil> element
             File Name: Basic_systemRequired.smil
      Media Components: 3 JPG
     Expected Behavior: If the BrushMedia module is supported, show sequence of colored boxes (using <brush>)
                        If BrushMedia module is not supported, do not show the document.
    -->
    <smil xmlns="http://www.w3.org/2001/SMIL20/Language"
          xmlns:HostLanguage="http://www.w3.org/2001/SMIL20/HostLanguage"
          xmlns:BrushMedia="http://www.w3.org/2001/SMIL20/BrushMedia"
          systemRequired="HostLanguage+BrushMedia" >
       <head>
          <layout>
             <region id="colorbox" top="0px" left="0px" height="240px" width="320px" />
          </layout>
       </head>
       <body>
          <switch>
             <seq systemRequired="BrushMedia">
                <brush dur="5s" color="#0000FF" region="colorbox"/>
                <brush dur="5s" color="#00FF00" region="colorbox"/>
                <brush dur="5s" color="#FF0000" region="colorbox"/>
             </seq>
             <seq>
                <img dur="5s" src="../images/frown.jpg"  region="colorbox"/>
                <img dur="5s" src="../images/smile.jpg" region="colorbox"/>
             </seq>
          </switch>
       </body>
    </smil>