extracting semantic text features from, the media content and the URL, wherein {HEAD ~ the extracting the semantic text features} is determined according to {TAIL ~ a set} of extraction rules, wherein the set of extraction rules comprises at least one rule specifying surrounding text be within a threshold semantic distance from a piece of the media content 
is determined according to
extracting semantic text features from , the media content and the URL , wherein { HEAD ~ the extracting the semantic text features } is determined according to { TAIL ~ a set } of extraction rules , wherein the set of extraction rules comprises at least one rule specifying surrounding text be within a threshold semantic distance from a piece of the media content
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL 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 OTH OTH OTH OTH OTH OTH