PVR_STREAM_EXTHDR_TYPE_MASK
#define PVR_STREAM_EXTHDR_DATA_MASK ~(PVR_STREAM_EXTHDR_TYPE_MASK | PVR_STREAM_EXTHDR_CONTINUATION)
type = (ext_header & PVR_STREAM_EXTHDR_TYPE_MASK) >> PVR_STREAM_EXTHDR_TYPE_SHIFT;