During a rewind operation, {HEAD ~ a reference picture} for {TAIL ~ a group} of pictures is decoded and stored into a reference frame buffer 
for
During a rewind operation , { HEAD ~ a reference picture } for { TAIL ~ a group } of pictures is decoded and stored into a reference frame buffer
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH