Hollywood film studios have pledged support for one of the competing formats battling for primacy in the DVD market.
The group supporting the HD DVD optical disc format for high-definition video is vying with the rival Blu-ray Disc format .
But Paramount Pictures, Universal Pictures, Warner Brothers New Line Cinema and HBO have all said they will use HD-DVD.
The studios did not spell out the details of any releases and there was no mention of timing, with the exception of a pledge from Universal to have content available by Christmas 2005.
The support is a coup for the group because it is the first time that any Hollywood studio - with the exception of Sony Pictures, which is owned by Blu-ray Disc-backer Sony - have come down firmly on the side of one of the formats.
In October, Twentieth Century Fox 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 current 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, including Dell, Hewlett-Packard, Hitachi, LG Electronics, Matsushita (Panasonic), Mitsubishi, Philips, Pioneer, Samsung, Sharp, Sony, TDK, Thomson Multimedia, and Twentieth Century Fox.
Sony has also said that it plans to use Blu-ray Disc in the successor to its PlayStation 2 console.
At present the only hardware available is for the Blu-ray Disc format. Sony and Panasonic have released HDTV (high definition television) recorders in Japan, and Sharp will sell a similar product shortly, although these machines do not include support for the Blu-ray Disc movie format, which is still being standardised.
On the HD-DVD side, Toshiba, NEC and Sanyo are all on schedule to release hardware in 2005.
Toshiba plans to produce an HD-DVD player for about one third of the current $3,000 (£1,600) price of Blu-ray Disc hardware.
Optical-disc maker Memory-Tech has said it is ready to begin producing HD-DVDs. The company has demonstrated test production and currently has five production lines each capable of producing 700,000 discs per month. By the beginning of 2005 it plans to add a sixth line, said Shiroharu Kawasaki, president and chief executive of Memory-Tech.
Martyn Williams and Paul Kallender write for IDG News Service