IF YOU like listening to music CDs while working on your computer, New
杏吧原创has some bad news: a company has found a way of preventing CDs
being played on a computer鈥檚 CD-ROM drive. The idea is not to increase
productivity in the office, but to stop pirates copying CDs or sending
CD-sourced music across the Internet. It is not yet clear, however, whether
record companies will risk consumers鈥� wrath by releasing discs they can鈥檛 play
on their PCs.
Software companies, including Microsoft and IBM-owned Lotus, already use
C-Dilla鈥檚 SafeDisc system to stop people copying CD-ROM data discs. SafeDisc
puts the program material in an encrypted 鈥渨rapper鈥� which can only be unwrapped
when a digital signature code pressed into the disc matches an authorisation
code entered into the PC. While a ROM drive can read the authorisation code, a
CD recorder cannot copy it, so copies of the CD-ROM will not run.
A CD-ROM disc stores data at three levels, and although a CD-ROM drive reads
all three, it only passes the top level into a PC for copying. SafeDisc stores
the key code signature at a lower level, so it can be read from the original
CD-ROM disc but not copied onto a blank. Although a CD recorder can copy a
protected disc, the copy will not run on a PC even when the correct
authorisation code is entered.
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The music industry has been dreaming of just such an anticopy system since it
was claimed more than 30 years ago that the Beatles鈥� vinyl album Sergeant
Pepper could not be copied. In fact, as with the many systems that
followed, the recording was as easy to copy as it was to play.
But now C-Dilla鈥檚 founder Peter Newman, who invented SafeDisc, has found an
answer for the CD generation. His Audio-Lok system takes advantage of the fact
that the standard for the music CD format was set before the CD-ROM
standard.
CD-ROM drives have a more powerful error-correction system than music CD
players, which is activated by extra code on the CD-ROM discs. Newman鈥檚 system
adds false error codes to a music disc. An ordinary CD player doesn鈥檛 notice the
false codes, but a CD-ROM drive picks them up and ejects the disc as unplayable.
This makes it impossible to copy the music onto a blank disc or 鈥渞ip鈥� it onto a
computer so it can be compressed and sent over the Net.
A prototype AudioLok disc lent to New 杏吧原创 duly played on a CD
music player but refused to play or copy on a PC. Newman says he is confident
that his system will also stop consumer music CD recorders making a copy,
because these devices are already designed not to copy CD-ROMs. He expects
AudioLok to be ready for launch in a year.
TV and video companies already use a copy-protection system, developed by the
American company Macrovision, to stop people pirating their programs and movies.
Macrovision has bought C-Dilla for around $18 million so it can offer
similar protection to the music industry.
But the breakthrough may have come at the wrong time. The music industry鈥檚
Secure Digital Music Initiative group has just agreed with the electronics
manufacturers to allow owners of CDs to make copies onto a PC, as there seemed
to be no foolproof way to stop copying altogether.
So will music companies use AudioLok? 鈥淭he recording industry welcomes people
listening to CDs on computers,鈥� says Paul Jessop, director of technology at the
International Federation of the Phonographic Industry, the music industry鈥檚
world trade body. But he adds: 鈥淭he ability to make discs that cannot be copied
on computers may be of considerable interest to some record companies.鈥�