(REUTERS) -- Comcast Corp. on Wednesday posted a better-than-expected rise in quarterly profit driven by strong video and Internet subscriber additions, though it was hindered by weak performances at its NBC Universal broadcast and movie units.

The leading U.S. cable TV provider added 336,000 Internet subscribers and lost just 17,000 video customers -- its best quarterly video numbers in five years.

Analysts at Collins Stewart had expected Comcast to add 242,000 Internet subscribers and lose as many as 140,000 basic TV subscribers.

Comcast added 146,000 phone customers, below Collins Stewart's forecast of 170,000 additions.

Comcast, which controls NBC Universal, said strong cash flow growth at its cable networks was offset by a poor performance at the NBC broadcast business and its Universal studio.

Cable networks, including USA, Bravo and E!, saw operating cash flow jump 16.2 percent to $930 million, but NBC cash flow turned negative at $52 million. Universal's operating cash flow nearly halved to $91 million. The theme park business posted flat operating cash flow performance at $191 million.

Fourth-quarter net income rose to $1.29 billion, or 47 cents a share from $1.02 billion, or 36 cents a share, a year before.

Analysts had on average forecast profit of 41 cents per share, according to a poll by Thomson Reuters I/B/E/S.

Revenue rose 3 percent to $15 billion.

Comcast raised its dividend by 44 percent to 65 cents a year and announced a new share buyback program of $6.5 billion, with a pledge to spend $3 billion in 2012.