Embodiments receive multimedia data, detect {HEAD ~ portions} having {TAIL ~ specified features}, and output a corresponding subset of the multimedia data 
having
Embodiments receive multimedia data , detect { HEAD ~ portions } having { TAIL ~ specified features } , and output a corresponding subset of the multimedia data
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH