1080P高清
http://movietrailers.apple.com/movies/sony/baghead/baghead_h1080p.mov
720P高清
http://movietrailers.apple.com/movies/sony/baghead/baghead_h720p.mov
480P高清
http://movietrailers.apple.com/movies/sony/baghead/baghead_h480p.mov
高清晰版
http://movietrailers.apple.com/movies/sony/baghead/baghead_h640w.mov