a first frame buffer for storing {TAIL ~ a reference picture}, wherein {HEAD ~ the reference picture} comprises a mid point picture in an EP to EP stream during one time period, and a clean reference picture during another time period 
a first frame buffer for storing { TAIL ~ a reference picture } , wherein { HEAD ~ the reference picture } comprises a mid point picture in an EP to EP stream during one time period , and a clean reference picture during another time period
OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH