private void TestType()
{
int hr;
TimelineMajorType t;
hr = m_pVideoGroupObj.GetTimelineType(out t);
DESError.ThrowExceptionForHR(hr);
Debug.Assert(t == TimelineMajorType.Group, "TimelineType");
hr = m_pVideoGroupObj.SetTimelineType(TimelineMajorType.Effect);
Debug.Assert(hr == E_INVALIDARG, "Not supported");
}