    <!--
                Copyright: Copyright 1998-2001 W3C (MIT, INRIA, Keio), All Rights Reserved.
    See http://www.w3.org/Consortium/Legal/.
    Author: Muriel Jourdan (Muriel.Jourdan@inrialpes.fr)
               Version: Apr. 3, 2000, v1
                Module: SMIL Timing & Sync Module
               Feature: begin attribute and Negative Delay
             File Name: Negative_Delay4.smil
      Media Components: 2 JPG
     Expected Behavior: image1 begin to be shown from t=3s to 8s.
                        image2 begin to be shown from t=0s to 4s.
    -->
    <smil xmlns="http://www.w3.org/2001/SMIL20/Language">
      <body>
        <par >
          <img id="image1" src="../images/smile.jpg"  dur="5s" begin="3s"/>
          <img id="image2" src="../images/frown.jpg"
               begin="image1.begin-6s" dur="7s"/>
        </par>
      </body>
    </smil>