Media Wonk

Murky Vistas - January 29, 2007

At the risk of losing cool points, I think Microsoft is getting a bit of a bum rap over some of the content-protection features baked into Vista, particularly the complaints about down-resolving high-def video when it’s sent over non-HDCP compliant connections.

Insofar as Vista will be used in the PC playback of HD DVDs and Blu-ray Discs, even Gates & Co. had little choice in the matter.

Down-resolution is a requirement of the Advanced Access Content System (AACS) license covering the encryption used for both high-def DVD formats. Under the implementation and robustness rules of the license, any playback system, whether hardware or software, must recognize and respond to a down-rez “flag” (officially the Image Constraint Token) if set by the content owners.

When the flag is up, the device must send full 1920x1080 video only over outputs protected by HDCP encryption (i.e. HDMI outputs). If the flagged video stream is being sent over analog connections (such as VGA port), the device is required to drop the resolution to 960x540 lines.

If the flag is not set, the device is free to send full HD over analog.

In order to support HD DVD and Blu-ray playback in Vista, Microsoft must be an AACS licensee, and must abide by its terms and restrictions.

The purpose of the Image Constraint flag is to address to so-called analog hole, by which unprotected analog content can be captured and re-encoded for distribution over the Internet. But forcing down-rezzing, the content owners lessen the chances that they are handing would-be pirates the best quality masters.

As a member of the eight-member consortium that came up with the scheme, Microsoft actually fought pretty hard to keep ICT out of the license. But the studios in the group (Warner and Disney) dug in their heels.

The real question is, what did Microsoft get for ultimately going along?

Although it opposed down-resolution, Microsoft’s top priority in the AACS negotiations was to secure so-called managed copy.

Under a managed-copy regime, consumers could rip their high-def discs to a hard drive, where it would be protected by an AACS-approved digital-rights management scheme, for streaming over a home network.

So keen was Redmond for the idea that it volunteered to maintain the backend servers needed to authenticate managed-copy transactions at its own cost.

Simultaneously, Microsoft was also pushing within the DVD Copy Control Association, which oversees the CSS encryption used to standard-def discs, to incorporate managed copy into the current format.

Although there was no explicit quid pro quo, it more or less worked out that Microsoft gave in on down-resolution and the studios agreed to managed-copy.

Having gotten what they wanted on down-resolution, however, the studios now seem in no particular hurry to complete negotiations over the details of managed copy.

High-def hardware and software makers today are operating under an “interim” license, which does not permit managed copy because the DRM and copying rules have yet to be agreed on.

Final details of a managed-copy scheme are supposed to be covered by a “final” license agreement. But the final license is now eight months overdue and still nowhere in sight.

On the standard-def side, meanwhile, the studios’ most-recent proposal for managed copy reprised a host of demands that the consumer electronics and IT companies involved in the discussions thought had already been considered and rejected.

And so the managed-copy negotiations drag on.

And Microsoft continues to take heat for holding up its end of the implied bargain.

Wonder how that’s going over in Redmond?

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