Feeds

Macrovision CDS-300 version 7 beta

A CD lock-in tech that only annoys P2P traders?

  • alert
  • submit to reddit

Remote control for virtualized desktops

Exclusive Macrovision describes version 7 of its CDS-300 copy protection system as a major step forward in keeping P2P users' hands off copyright content for which they don't have the distribution rights. Having seen a demo of the alpha release, which performed as advertised, we were nonetheless pleased when a copy of the latest beta version turned up in The Register's mailbag.

Since the alpha release, Macrovision has shifted the system's focus away from tinkering with the contents of the CD Audio session - a technique it calls 'passive protection' - and toward smarter use of multiple disc partitions, or 'session protection'.

That should help appease hi-fi purists concerned that the addition of deliberate errors into the audio datastream reduces the effective lifespan of the disc. CD playback requires a hefty level of error correction to yield the sound clarity for which the medium is famous. Adding noise to the audio content may fool ripping software but, say some observers, it also further taxes CD players' error correction systems, which may already be having to cope with scratches and grease on the disc's surface.

Beyond a certain point, the theory goes, the error correction mechanism will not be able to cope, so by adding errors to the datastream, Macrovision is reducing the amount of damage a disc can take before it becomes unplayable. We'd say disc buyers should take better care of their CDs, but Macrovision has nonetheless scaled this element of its copy protection scheme right back.

Indeed, we were able to duplicate the CD Audio part of the disc - the Red Book session - and there was none of the irritations such deliberate errors are supposed to induce in computer-made copies.

Session player

But back to session protection. Essentially, this is the old technique of hiding multiple disc sessions from systems for which those sessions are irrelevant. When CDs might once have incorporated data as a 'track 0', which would have shown up on a CD player but played as either white noise or silence depending on the sophistication of the hardware, multi-session mastering allows, say, the Mac OS partition to be hidden from Windows users and vice versa - and for both to be ignored by a CD player. Multiple sessions are now part of the CD spec, courtesy of the so-called Blue Book, which covers Enhanced CDs and was developed by Philips, Sony, Microsoft and Apple.

CDS 300 Version 7 UI

On the office Windows XP box, the CD Audio session is thus hidden from inspection - only the PC-compatible session appears in the My Computer folder. Holding down the Shift key prevents the session from auto-running, but double-clicking amounts to the same thing: Macrovision's own Flash-based applet is launched and instances Windows Media Player (WMP) for playback. Session protection ensures you can't access the CD Audio even if you do hold the Shift key down, at least not through Windows itself.

Exploring the disc session reveals the 192Kbps WMA files offered to PC users as an alternative to the Red Book tracks, along with the various DLLs and CD burning code - of which more later.

Top 5 reasons to deploy VMware with Tegile

Next page: Licensed to ill

More from The Register

next story
BIG FAT Lies: Porky Pies about obesity
What really shortens lives? Reading this sort of crap in the papers
Assange™ slumps back on Ecuador's sofa after detention appeal binned
Swedish court rules there's 'great risk' WikiLeaker will dodge prosecution
You think the CLOUD's insecure? It's BETTER than UK.GOV's DATA CENTRES
We don't even know where some of them ARE – Maude
NSA mass spying reform KILLED by US Senators
Democrats needed just TWO more votes to keep alive bill reining in some surveillance
prev story

Whitepapers

Why and how to choose the right cloud vendor
The benefits of cloud-based storage in your processes. Eliminate onsite, disk-based backup and archiving in favor of cloud-based data protection.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Go beyond APM with real-time IT operations analytics
How IT operations teams can harness the wealth of wire data already flowing through their environment for real-time operational intelligence.
How to determine if cloud backup is right for your servers
Two key factors, technical feasibility and TCO economics, that backup and IT operations managers should consider when assessing cloud backup.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?