The group supporting the HD-DVD optical disc format for high-definition video has received a boost in its battle against the rival Blu-ray Disc format with pledges of support from a number of Hollywood studios.

The format will be used by Paramount Pictures, Universal Pictures, Warner Bros. Pictures and New Line Cinema, the HD-DVD group said on Monday. It will also be used by HBO, Warner Bros. announced the same day.

The support is a coup for the group because it is the first time that any Hollywood studios – with the exception of Sony Pictures, which is owned by Blu-ray Disc-backer Sony – have come down firmly on the side of one or other of the formats. In October, Twentieth Century Fox Film joined the Blu-ray Disc Association, but stopped short of committing to release any content in that format.

HD-DVD and Blu-ray Disc use blue lasers in their optical systems. The discs are the same size as CD or DVD discs but offer data storage capacities several times greater than that of DVD. The extra capacity provides enough room to hold high-definition versions of movies and other content.

HD-DVD is backed by Toshiba and NEC and is being developed under the umbrella of the DVD Forum, the group that developed the DVD format. Blu-ray Disc has more major backers: Dell, Hewlett-Packard, Hitachi, LG Electronics, Matsushita Electric Industrial (Panasonic), Mitsubishi Electric, Philips Electronics, Pioneer Electronics, Samsung Electronics, Sharp, Sony, TDK, Thomson Multimedia and Twentieth Century Fox.

To date, Sony Pictures is the only movie studio to announce plans to release content on the Blu-ray Disc format. Sony Computer Entertainment has also said that it plans to use Blu-ray Disc in the successor to its PlayStation 2 console.