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