With fresh data showing that Hollywood’s crucial home entertainment market shrank yet again in 2010, six of Hollywood’s biggest studios are rolling out plans for boosting online sales of movies and TV shows.

The technology, called Ultraviolet, was unveiled this week at the Consumer Electronics Show in Las Vegas after four years of development. It will be launched in early summer and allow customers to download videos on multiple devices and share them with up to six family members or friends.

Backing the initiative are Warner Bros., Paramount Pictures, Sony Pictures, 20th Century Fox, Universal Pictures and Lionsgate. Walt Disney Studios is not part of the consortium because it is moving ahead with its own similar plan, called KeyChest.

Industry research has shown that the inability to play video downloaded from the Internet on more than one device and share it has hampered growth in digital distribution. Hollywood hopes that lifting those barriers will accelerate online sales of movies and TV shows, reduce piracy and allow the home entertainment market to grow again after five consecutive years of decline.

Indeed, the Ultraviolet announcement came just as new data released Thursday by industry trade organization Digital Entertainment Group showed that total revenue from DVD, high-definition Blu-ray discs, and digital sales and rentals of movies and television shows in the U.S. declined 3 percent to $18.8 billion in 2010.

While the numbers were down, they nonetheless marked an improvement over 2009, when home entertainment revenue fell 7.6 percent — the steepest decline in a decade.

— Los Angeles Times