A consortium of 55 entertainment and technology giants hoping to standardize digital formats for video playback said on Monday it will start beta testing in the fall as it added two more companies to its ranks and unveiled its brand name, Ultraviolet.

The Digital Entertainment Content Ecosystem (DECE) said LG Electronic and Marvell Technology Group Ltd joined the group aiming to standardize and streamline the digital supply chain by using cloud-based technology.

For instance a consumer with an Ultraviolet account can buy a copy of a film, store it in a digital locker and then view it in various ways from a cable company's video-on-demand service to a game console.

Driven largely by Hollywood seeking to offset a sharp decline in DVD sales, the DECE has recruited industry behemoths from technology firms Adobe Systems Inc and Cisco to cable giant Comcast, but has two big holdouts -- Walt Disney Co and Apple Inc.

Disney is developing a competing system called KeyChest, while Apple sells songs and videos in proprietary formats through its iTunes Store.

We have enough critical mass to launch, said Mitch Singer, president of the DECE and chief technology officer for Sony Pictures, noting the group is talking with more potential partners and chose the brand name Ultraviolet in part because it is a natural extension of Hollywood's Blu-ray high-definition format.

(Reporting by Susan Zeidler; Editing by Tim Dobbyn)

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