Cable Industry Struggles With Set-Top DVI Links


It's a new little plug in the back of the digital set-top box, and Hollywood is hoping it will thwart video pirates in TV's new all-digital environment.

But the Digital Visual Interface inputs that cable set-top makers are adding to their high-definition products in the coming months also add some longstanding consumer concerns.

In particular, some industry observers fear that DVI's "view-only" content protection could allow the big film and television studios to put a headlock on digital content and stifle consumers' home-recording rights.

As more digital-cable subscribers purchase high-end, high-definition digital TVs, the need for an all-digital connector has become more apparent.

Up until now, consumers have been required to use analog inputs to hook their cable boxes up to these pricey digital sets. But doing so causes some loss in digital picture quality, and doesn't provide any content protection.

Thus, consumer-electronics manufactures have begun to incorporate two new digital-connection options: Digital Visual Interface and the Institute of Electrical and Electronics Engineers' IEEE-1394 data-transport bus, also known as FireWire.

It's uncompressed

A product of the personal computer industry, DVI relays uncompressed display signals between the cable box and TV set, providing what many consider the superior video quality of the two standards.

While the massive storage size of uncompressed video is likely enough to prevent most consumers from capturing it for hard-disk storage, DVI's high-bandwidth digital copy protection (HDCP) protocol locks the content into display-only format, so it can't be recorded on a separate device.

Producers can configure their digital content for DVI-only output, so if the devices don't support the DVI HDCP, it will not be displayed.

For its part, FireWire has become a popular way to shuttle compressed video data between multiple home devices, ranging from digital camcorders to video recorders, PCs and printers.

It also has copy-protection features, courtesy of the "5C" digital-transmission content protection (DTCP) scheme, but DTCP can be configured to allow for a single digital copy.

Monopoly feared

While DVI is now more prevalent on digital TVs than FireWire, there are those who worry that too much DVI might be a bad thing.

That's why the Consumer Electronics Association supports incorporating display-only DVI, but also doesn't want the connector to gain a DTV monopoly.

"Our position is that it is a marketplace-driven decision," said CEA vice president of technology policy Michael Petricone. "From a policy standpoint, our chief concern is ensuring that no matter which interface is used,

Hollywood continues to respect consumers' normal and customary home-recording rights."

There have been whispers that the Hollywood studios would not release their properties until all televisions come equipped with only a DVI digital input, Petricone noted.

"That is something that troubles us," he said. "We would have no problem if pay-per-view movies were non-recordable. But we would have a problem if the content companies sought to prevent consumers from recording, say, free over-the-air broadcast recording."

The Motion Picture Association of America has no such plan, according to executive vice president and Washington general counsel Fritz Attaway.

"We have been accused of trying to create a situation where our content will only go through a DVI interface, which will prevent anything but display, and that is simply not true," Attaway said. "We recognize that DVI is an effective content-protection tool in certain instances, and we support it. But we also support 5C, and we have an interest in permitting copying."

In fact, some film studios' distribution plans count on the ability to record video, particularly those tied to pay-TV outlets such as AOL Time Warner Inc.'s Home Box Office and Viacom Inc. unit Showtime Networks Inc.

"It is a very important part of their marketing," Attaway said. "So we have got to enable HBO to allow their customers to do this. So we support DTCP, because it allows copy-once."

Possible potpourri

Like the CEA, the MPAA advocates using DVI and FireWire as a sort of tag-team digital connection.

For instance, in a cable household DVI could link the TV set and a primary digital set-top box. Programs can still be recorded on a digital box equipped with a hard drive, but if a show is encoded only for DVI output, then it may only be displayed on a DVI-enabled screen.

The FireWire output, meanwhile, could be used to ship video that can be copied from the box to other devices.

"The bottom line is that we don't see one perfect technology that will be used in every situation to protect content," Attaway said. "There are going to be a number of different technologies that will be used in different types of situations to provide content that consumers want to purchase. It all boils down to doing what the consumer wants."

But for the CEA, the policy regarding how these digital connections are used in future TV sets and set-top boxes is still unclear.

"There need to be clear agreements with Hollywood, that Americans' noncommercial home-recording rights are respected and protected," Petricone said. "Our focus is not so much on the technology. It's on how that technology is used."