Q&A: NAB Chief Engineer Lynn Claudy Talks HD
Lynn Claudy is NAB
senior vice president of science and technology, and has been directly involved in furthering HD and the DTV transition within American broadcasting for many years. He recently spoke with HD Notebook
:HD Notebook: As NAB’s top engineer and technical guru, how do you see the 2009 cutoff of analog services shaping up as NAB and other parties within the industry work to educate consumers in the next 16 months?Claudy:
There are certainly practical technical challenges at the station level, given that over 600 stations will be changing their operating DTV channel before the stroke of midnight on Feb. 17, 2009. And we’re hopeful that the FCC will accommodate those stations’ needs for flexibility—as the industry has requested in comments filed in the FCC’s Third Periodic Review on DTV. But the difficulties for stations to navigate the end of the DTV transition remain somewhat of an open issue, pending decisions from the FCC.
On the consumer education side, having the February 2009 date solidly in place has forced the industry to really focus on the issue of transitioning the general public to the all-digital broadcast era, and there is a large groundswell of effort getting underway on that front. Overall, we see this not only as a mandate to reach current over-the-air-only viewers and make sure they are not disenfranchised when analog broadcasts cease, but it’s an opportunity to tout the virtues and benefits of digital broadcast television generally, and actually grow the over-the-air DTV audience, with HDTV as the centerpiece.
Free over-the-air digital broadcasts that are at technical parity with cable, satellite and telco offerings are a compelling proposition to consumers, and even among pay subscribers, having an antenna connected to their wired sets is a value added benefit—after all, cable and satellite service go out from time to time, not all broadcast services are carried on cable or satellite, and the immediacy of access to broadcast digital television can make a big difference to consumers in times of crisis and emergencies. The bottom line is when all the dust settles after the transition date, the new digital broadcast service will be much better than the old analog broadcast service, and opportunities for new services and revenue will expand considerably. HD Notebook: Using the ‘wisdom of 20/20 hindsight,’ has your experience with the transition prompted any issues or factors (for better or for worse) that NAB had not foreseen?Claudy:
One of the important lessons we’ve learned is that it was critical to include all stakeholders in having a mandated role in the overall DTV transition, and not just assume that putting requirements on broadcasters alone would lead to a timely completion of the transition through marketplace forces.
Other than adopting the DTV standard itself in 1996, I think the most important decision made by the FCC to spur the transition was the mandate to eventually require the inclusion of DTV tuners in all television sets. Not only was that a seminally important decision in itself, but it signaled a general change in thinking from that point forward that recognized the DTV transition as an entire system in transition—including consumers—and not just a broadcast station transition.
Had we, meaning both industry and government, started out with more of a holistic-systems approach to the transition from the beginning, perhaps the path would have been a little smoother. The lesson for planning future services is to make sure all stakeholders are involved, and that business models are an integral part of the planning procedure as the technical process begins.HD Notebook: Do you see us living in a world of 720p, 1080p and 1080i for many years to come, or will other formats or technologies replace them relatively quickly? Also, in the short term, will 1080p be the preferred production and transmission format of choice by broadcasters?Claudy:
Production at the highest resolution feasible generally makes sense because it provides headroom for any desired downstream processing. Beyond that, video format choice will increasingly be more geared toward matching the intended end use. 1080p is a fine choice for very large screen viewing, assuming of course there is eventually an agreed-upon way to transmit it, which isn’t the case now except at film rates.
But at the portable-TV screen sizes, resolution differences between 1080 and 720 lines are of little consequence. And for the prospect of new services aimed at mobile DTV reception, with TV images on personal devices and cell phones, display resolution requirements are even lower. Eventually, choice of video formats becomes more about how to match bandwidth and data capacity to the array of services being provided, than it is about rigid dogma of Progressive versus Interlaced, or 1080 versus 720, or other numbers.