By Michael Kahn

SAN FRANCISCO:- In the battle over next generation DVDs, pornography could prove to be the XXX factor that helps determine a winner.

Thirty years ago, VHS toppled Betamax in part because of the adult film industry, and now some see blue movies playing a key role again as backers of HD-DVD and Blu-ray maneuver to make their formats the standard.

The stakes are high. As prices of high-definition televisions and DVD players fall, backers of the rival -- and incompatible -- formats are looking to tap a home and rental DVD market approaching $25 billion.

Yet so far, neither next-generation format has been able to land a knock-out blow.

James McQuivey, a principal analyst at technology research firm Forrester, said in the VHS-versus-Betamax war, porn provided a significant boost for the winning format.

He also noted the adult entertainment industry has often paved the way with new uses of technology -- such as streaming video on the Internet -- and said porn could help tip the scales in the current DVD format battle.

"If the porn industry wanted to break the logjam of HD-DVD and Blu-ray, it could," McQuivey said. "If they said 'We are going to go with HD-DVD' you would see a few million homes immediately go out and buy HD-DVD players. They have that power."

It is a potential weapon that one side, at least, has ignored. Instead, Blu-ray backer Sony Corp. blocked manufacturers from producing porn DVDs in that format -- a move that some say has pushed adult film studios into the camp of HD-DVD camp led by Toshiba Corp.

Steven Hirsch, founder of Vivid Entertainment Group, said Walt Disney Co. also refuses to use DVD makers -- known as replicators -- that press porn titles.

This makes finding a Blu-ray replicator willing to alienate Sony and Disney almost impossible for porn studios because the format requires costly new equipment and there are only a handful of replicators able to make such DVDs.

That isn't a problem for HD-DVD because that technology is based on previous-generation standards, which makes it far simpler and cheaper for companies to hire replicators to press their DVDs.

Hirsch said that Vivid -- home to adult film stars such as Jenna Jameson, Tera Patrick and Briana Banks -- found a willing manufacturer to press "Debbie Does Dallas ... Again," which the company plans to issue in April.

But the cost and difficulty of doing so for the sequel to the 1978 adult film classic "Debbie Does Dallas" clouds whether more adult films in Blu-ray will follow, said Hirsch, who declined to provide details on who is pressing the movie.

"We have been able to find a replication facility to do our title but it wasn't easy and it has deterred us for the most part from releasing titles on Blu-ray," Hirsch said. "That can be potentially problematic for Blu-ray."

Studios like Vivid say they have been shooting films in high-definition for years to build up a library, but so far the number of titles is only a trickle as the industry weighs the advantages of each format.

HD-DVD machines are cheaper but Blu-ray has backing of a majority of the mainstream studios and an advantage in that the format is compatible with the PlayStation 3, the latest version of Sony's popular series of video game consoles.

The founder of adult studio Digital Playground -- whose films include "Island Fever 3" and "Pirates" -- believes Blu-ray backers are erring in not embracing porn as they fight over billions of dollars in royalties.

"The reason they should want to work with us is that they are in a war with HD-DVD and in a war you would want as many people in your corner," said Joone, the Digital Playground founder who goes by one name.

Joone said in an ideal world Digital Playground would offer films in both formats. Instead, he sees Sony and other Blu-ray backers pushing the adult entertainment industry toward HD-DVD, whose supporters he said have welcomed porn producers.

"In general we need to have one format because it cuts down the confusion in the marketplace for the consumer," Joone said. "HD-DVD has helped us tremendously to get titles out."