Industry tries to control digital copying

Industry giants IBM, Intel, Matsushita and Toshiba are working together to make the digital copying of audio and video on your PC all but impossible.

The so-called 4C Group is proposing changes to the standard for hard disks which would allow copy protection to be incorporated into PCs, set-top boxes, digital VCRs and personal stereos which would effectively prevent the digital copying of audio and video.

The proposed new system, called Content Protection for Recordable Media (CPRM), provides a way of encrypting content so that it can be decrypted only by a compliant playback device. The scheme is also aimed at controlling the limited copying of the emerging high-quality pre-recorded audio DVDs, which offer either two channels of extremely high fidelity sound (24-bit sampling at 192KHz, compared with the existing CD standard of 16 bits at 44.1KHz) or six channels of audio still at a higher quality than CDs.

The owner of a DVD-audio disc will be able to make copies only by using a DVD recorder incorporating CPRM. Under the proposal, all disks will incorporate a unique serial number which is part of the security key used to encrypt the content. If an attempt to make a further copy is made, the serial number of the second disk will be different, and the song won't play.

Leading disk drive maker Western Digital is taking a neutral position. "The proposal of this standard is in the early stages," says a spokeswoman. "Our official position is that we are continually evaluating technologies such as those represented by 4C and while we respect the need for content providers to protect their copyrights we will consider such technologies only if our customers demand it."