- The Washington Times - Tuesday, April 22, 2008

MINNEAPOLIS (AP) - In Brent Swanson’s basement home theater, there should be nothing drab about “Battlestar Galactica.” He has a high-end projector that beams the picture onto a wall painted like a silver screen, and speakers loom in the corners, flanking two big subwoofers.

Yet when he tuned in Sci Fi HD for a recent episode filmed in high definition, the image was soft, and the darkest parts broke up into large blocks with no definition. Explosions, he says, were just dull.

“It kind of looked like they took the standard definition and just blew it up,” says Mr. Swanson, 33, a graphic designer and videographer who subscribes to Comcast Corp.’s TV service. “I couldn’t really tell if what I was seeing was really better than what I saw on regular television.”

As cable TV companies pack ever more HD channels into limited bandwidth, some owners of pricey plasma, projector and LCD TVs are complaining that they’re not getting the high-def quality they paid for. They blame the increased signal compression being used to squeeze three digital HD signals into the bandwidth of one analog station.

The problem is that viewers want more HD channels but many cable and satellite providers are at the limits of their capacity, says Jim Willcox, a technology editor for Consumer Reports magazine.

“They have to figure out a way to deliver more HD content through their distribution networks,” he says.

Compressing the signal is cheaper than undertaking costly infrastructure upgrades to increase capacity.

Satellite TV providers, including DirecTV Group Inc. and Dish Network Corp., also have the option of launching satellites to boost the number of HD channels on their systems.

Though information is nearly always lost when signals are compressed and then uncompressed, the process theoretically can be made unnoticeable to eyes and ears — and Comcast says it should be.

However, some viewers say they can see it. Mr. Willcox says complaints about compression have been showing up on Web forums, including the AV Science Forum, a site for serious audiovisual enthusiasts.

“It’s not exclusively Comcast, although Comcast, being the largest cable provider, is probably the largest target,” he says.

Derek Harrar, a Comcast senior vice president in charge of video, says the company recently began using new technology on some channels to compress three HD channels into the bandwidth of one analog station. Other channels continue to get the previous 2-to-1 compression.

In a posting on the AV Science Forum, Ken Fowler of Arlington compared Comcast signals with those on Verizon Communications Inc.’s all-fiber-optic network, which doesn’t have the same capacity limitations. Mr. Fowler found the higher-compressed HD stations, including Sci Fi, Animal Planet, the Discovery Channel, the Food Network and A&E;, fared particularly poorly.

He analyzed the signals by recording them on a digital recorder, then transferring them to a personal computer for analysis. He found much less data, measured in bit rates, was flowing to some channels than to others.

Mr. Fowler found the signals from the major networks and ESPN weren’t getting the increased compression.

He says he reran his analysis about two weeks ago and found “basically the same thing.”

Philadelphia-based Comcast wouldn’t identify specific signals that are 3-to-1 compressed, and a Sci Fi channel spokeswoman referred questions back to Comcast.

Mr. Harrar says the company works to make sure any new compression technology is invisible to consumers, but Comcast is “constantly monitoring our network and making adjustments” for best picture quality. The company has been rolling out the new compression technology at different times around the country.

In fact, postings on the AV Science Forum from early April suggest the Comcast network has improved in some places.

There are other reasons a high-definition picture can appear subpar: The source image might not have been recorded in HD, or the television’s settings, the viewing angle and even the ambient lighting in the room could be the cause.

New York-based Time Warner Cable Inc. has avoided many of the criticisms aimed at Comcast, although the companies are technologically similar and face the same capacity limits.

Time Warner spokesman Alex Dudley attributes that to his company’s testing procedures. He says that before Time Warner rolls out new technology that may affect image quality, it sets up two identical televisions in a lab, one with the old signal and one with the new. Technicians make adjustments until the pictures can’t be told apart.

“The testers are our engineers who we call ‘golden eyes,’ who have a proven track record of picking up subtle differences in picture quality,” he says.

Verizon’s FiOS doesn’t compress the signal once it receives it, and Mr. Willcox says it’s considered the picture quality “benchmark.” Verizon says the system is growing but is available only in parts of 17 states and has slightly more than 1 million subscribers — compared with more than 24 million for Comcast.

He says two possible solutions are on the horizon, an improved version of compression, called MPEG-4, and something called “switched digital video.”

Comcast and Time Warner Cable have introduced switched video on a trial basis across their networks. In concept, it’s like on-demand videos. The company sends only the channels the viewer is watching instead of all the channels at once.

However, switched video has its own issues, including possible slower channel-switching times and compatibility problems with digital video recorders.

Mr. Willcox says cable providers can’t afford to ignore quality complaints. Many customers already are picky about quality after paying $800 to $3,500 for an average-size HD-ready LCD television.

Mr. Swanson, the “Battlestar Galactica” fan, is sticking with Comcast for now.

“It hasn’t gotten bad enough for me to consider changing,” he says.

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