Section 14.280 of the Manual list the elements of an online video citation:
If you are citing a video clip that existed in another form before it was digitized and put online, see the following note. If you are citing a video clip that was formally published before it was digitized and put online, see this note.
“IBM's Watson Wins Person of the Year at the 15th Annual Webby Awards,” YouTube video, 2:47, posted by "TheWebbyAwards," June 13,
Video, with a principle subject, from an online source other than YouTube:
John Harwood, “The Pros and Cons of Biden,” New York Times video, 2:00, August 23, 2008, http://video.on.nytimes.com/