       |    |    |    |    |    |sgpd|    |    | Sample Group Description Box |
            +----+----+----+----+----+----+----+----+------------------------------+
            |    |    |    |    |    |sbgp|    |    | Sample to Group Box          |
            +----+----+----+----+----+----+----+----+------------------------------+
            |    |mvex|*   |    |    |    |    |    | Movie Extends Box            |
            +----+----+----+----+----+----+----+----+------------------------------+
       