Hollywood has locked horns with the technology industry over who will control digital entertainment and how it is watched.

好莱坞已经与技术行业制定数字娱乐控制权与观看方法。

The movie studios have described RealDVD as "StealDVD"

The six big film studios say a program called RealDVD violates copyright.

This week a San Francisco court could decide if DVD users can make personal backups the way people do with audio.

"The consumer should have the same fair use rights to copy DVDs just as they have for the last decade with music," said Bill Hankes of RealDVD.

RealDVD, which is made by RealNetworks, allows DVD owners to make digital copies of their discs onto a computer or laptop hard drive for their own personal use without having to pay extra.

Downloadable versions of many movies are available online, and some studios let users make a digital copy of a movie onto a computer by paying more for an "expanded edition" of a DVD.

Many believe this means the consumer is being made to pay twice.

Kevin Hunt who writes the Electronic Jungle column for the Baltimore Sun said: "For 11 years, since the Digital Millennium¹ Copyright Act (DMCA) made it illegal to bypass（绕开，忽视） any digital rights management protection system, the movie and music industries have fought a war ostensibly（表面上，外表上） against piracy².

"In reality, it has been a war against the consumer, designed to make people pay more than once for the same song or album or movie."

Figures show the DVD market in the US was worth almost $22bn in 2008

'Steal DVD'

At the heart of the case the movie studios, represented by the Motion Picture Association of America (MPAA), claim that RealDVD is illegal under the DMCA.

The Association said the software bypasses the copy protection built into DVDs meaning that users could copy a DVD and share it around. The studios have described the product as "Steal DVD."

The real fear being expressed is that the technology would enable people to "rent, rip, and return" DVDs.

These are the terms used to describe someone who rents a DVD, copies the content onto a hard drive and returns the movie without ever paying for the unauthorised copy.

"Our objective is to get the illegal choices out of the marketplace and instead focus constructively³ with the technology community on bringing in more innovative⁴（革新的，创新的） and flexible legal options for consumers to enjoy movies," Greg Goeckner, executive vice⁵ president and general counsel, MPAA told the BBC in an e-mail statement.

RealNetworks, which makes RealDVD, claimed that in actual fact the company has enhanced the security of the product.

"We have added an extra layer of security encryption（加密术）, the same the government uses, to ensure piracy is not a possibility," said RealDVD spokesman Mr Hankes.

A digital version made using RealDVD can only be played on the computer that made the copy.

The DVD Copy Control Association, which is primarily responsible for the copy protection of DVDs and also suing RealNetworks, told the BBC it would not comment until the case is resolved.