OTHER TECH

Speaking in Codec So, are these broadcasters trying to cheat us? Even though HDTV has been around for a while now, program providers are still on a learning curve. Putman thinks they don't realize that reduced bit rates compromise picture quality because everything looks fine in their control rooms. But the gear in a lot of control rooms is hardly state of the art. At a recent HDTV conference, Putman asked attendees what type of TVs they used to monitor images, and several said they had only 30-inch standard-def sets.

The critics think they see some relief on the horizon, however. Several claim that HD channels compressed with MPEG-4 - the advanced video codec DirecTV is using for new HD channels - look better than ones encoded with the older MPEG-2 standard. (MPEG-4 is designed to be more efficient than MPEG-2, needing only half the bit rate to deliver the same picture quality.)

But if some are seeing better pictures with MPEG-4, John Turner thinks it's just another example of the collective unconscious at work. "Unless you can quantify things, it's difficult to say 'my picture sucks'," he says. "Digital TV is very complex, and many things can account for a bad viewing experience."

Turner believes that the broadcast networks and big pay-TV channels such as HBO have agreements that force program providers to send signals of the same quality as the ones they receive from the programs' creators. "If cable or satellite fooled around with this, they'd be cutting their throats," he says.