A method of decoding, composing and rendering a scene. First information is obtained, the first information including a part of a MPEG-4 BIFS scene description stream and at least one coded MPEG-4 media stream. The first information is decoded by invoking a BIFS scene decoder and one or more specific media decoders that are required by the scene. Second information is obtained, the second information including a second part of a BIFS scene description stream that contains a reference to an external application. The second information is decoded by invoking the BIFS scene decoder and an external application decoder. An integrated scene is composed, the integrated scene including one or more decoded MPEG-4 media objects and one or more external application objects specified in the decoded scene descriptions streams. The composed integrated scene is rendered on a display.