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