In {HEAD ~ another embodiment}, {TAIL ~ the reference picture} is a clean reference picture in a HITS stream 
In { HEAD ~ another embodiment } , { TAIL ~ the reference picture } is a clean reference picture in a HITS stream
OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH