Amazon and TiVo said they were launching a service to deliver films and television shows bought or rented online directly to television sets. The US companies are testing an "Amazon Unbox on TiVo" service that lets people select shows or movies at the online retailer's website and have them sent to TiVo subscribers.

The original Amazon Unbox video service, launched in September 2006, lets users download films or television shows to personal computers or mobile devices compatible with Windows Media software.

The new service directs Unbox downloads to TiVo digital recording boxes linked to televisions.

"By teaming up with TiVo, we are offering our customers another great way to watch their Unbox videos," said Amazon vice president Bill Carr.

Studios selling shows or films at Unbox include CBS, Paramount Pictures, Universal, Warner Brothers Entertainment and Lionsgate, according to Amazon.

Unbox on TiVo is being tested by a group of TiVo subscribers and will "be available soon," the companies said in a joint release.

"TiVo is taking the best way to watch TV and making it the best way to get popular movies and television shows from major Hollywood studios," said TiVo chief executive Tom Rogers.

"Now, TiVo subscribers can rent and purchase movies and TV shows and download them to their television set -- all without leaving their homes."

Founded in 1997, the digital television recording pioneer has had skyrocketing success with its set-top service which enables viewers to automatically record programming, skipping over commercial breaks.