Some of my thoughts on Digital Television
January 16, 2012
FIRST: People are always asking me,
"Dick, which High Definition format is better, 1080p, 1080i, 720p, 480p?"
Yikes.
Well, I hate to do this to ya, but it kinda depends ... really! Oh, stop whining! Here's why.
- There are actually as many as 19 different HDTV/EDTV "standards". 19 different standards? Doesn't sound very standard to me. Fortunately for us, only a few are in actual use (at this time).
- Most commonly used? 1080i and 720p, which require about the same bandwidth when showing live action. A 1080i image has roughly twice as many pixels, while 720p shows twice as many frames per second.
- While showing films at 24 frames per second, 720p requires about half the bandwidth as 1080i. Do YOU really care about that? You probably shouldn't - read on.
- A common statement is that 720p is better for sporting events, while 1080i looks better for documentaries, dramas, and most things that come 24 frames per second. No comment.
Stop worrying about it - you have no control over it, anyway. The networks have each picked one format and they stick with it for all their shows. ABC, ESPN, and FOX have chosen 720p. Other major networks are using 1080i. For the most part, local network affiliates (your local TV stations) have chosen to use the same format internally as their respective network providers. We can only hope that someday they will all choose the format according to the content rather than according to whim. Your receiver can handle it, and so can most (if not all) of the equipment currently in use by broadcasters.
It has been stated that one format or another is actually superior. The folks who favor 720p are pretty vocal. However, they appear to ignore the fact that still images will look better in 1080i. They talk about flicker, interlace, etc. But most people will never notice these things unless something has been introduced into the path that exaggerates these factors (they are not always errors).
OK, let's talk about bandwidth. (Bandwidth refers to the amount of "room" the TV signal takes up within a given channel.) Although none of the cable, DSS, FiOS, or other non-broadcast providers will talk about it in their promotional material, they ALL use some form of compression (aka bandwidth reduction) during the transmission of television signals over their equipment. The reason they use compression is that, without it, you (the consumer) would never get those hundreds of TV channels to select from (everyone wants their MTV). Each channel takes up space (bandwidth) and unless you compress (or "Bit-Rate Reduce") the TV signals, you won't get very many of them on your cable or DSS system.
So, what's wrong with that? More channels is good, right? Well, the problem is that every bit you throw away is a bit you'll never see again! Sometimes, depending on the content you are viewing, it won't matter - other times it will. But they'll never tell you (or anyone else) how MUCH compression they are using (how many bits did they actually throw away?) So, you really don't have any qualitative way to tell who's delivery system provides the best picture quality to your TV set - its purely subjective - and you are left to decide for yourself. I'd like to help but they won't tell me either. It really is a closely-guarded secret.
Anyway, the very best way to view HDTV is by using your own TV antenna (but that's not practical for everyone). That way, you will get every bit (pun intended) of quality the broadcaster puts into his local product (this doesn't mean that some of what you see wasn't already compressed before it got into the local guy's facility - he can't do anything about that). However, you will forego access to "non-broadcast" content such as HBO, Discovery, and "Local Access". But if they are doing any local origination such as news, documentaries, etc. you will see it as it was intended, and it will be beautiful.
A few HD Definitions. 1080i and 720p are BOTH High Definition television (HDTV) formats and usually MOST people (that means you & I) can't see the difference. 480p is known as Enhanced Definition TV (EDTV) - it is NOT High Definition! 480i is Standard Definition TV (NTSC/SDTV). Although you will see it mentioned, NO "over-the-air" 1080p broadcasting exists at this time.
(OLD) NEWS FLASH - Congress Delays Analog Shutoff
After initially rejecting moves to delay the DTV transition date until June, the House voted today to do just that. This afternoon, the House took up the DTV delay bill passed by the Senate last week and gave its approval - with 264 members voting in favor and 158 opposing; 10 members of Congress did not vote on the bill.
As soon as President Obama signs the bill (a foregone conclusion since his administration requested the delay), consumers will have an additional 116 days to get their digital television house in order. The new last day for full power analog broadcasting is June 12, 2009.
As expected, the vote was largely on party lines, with only 23 Republicans voting in favor of the bill and 10 Democrats opposing it. Backers of the delay claimed six million over the air households risked being unready on Feb. 17 and also cited a bankrupt NTIA converter box coupon program as reasons for adding three months to the transition. The program ran out of funds in December and is building a 3 million-plus waiting list for the vouchers.
Opponents argued that extending the date was unnecessary and would only confuse citizens further.
For broadcasters, it will be a case of deciding what's more important: risk losing potential audience and alienating those that aren't ready by pulling the plug early and saving money; or holding fast to the June 12 deadline with aging analog transmitters.
Nothing in the bill will prevent stations from making the transition early, so long as they follow the current procedures for early shut-off of analog broadcasting. However, much will need to be done - and quickly - to update PSAs and marketing campaigns to alert consumers to the new deadline.
OK, so what's the bottom line?
If you use an antenna exclusively to receive your television programming, since June 12, 2009 the only way you have been able to receive and view over-the-air television with an older analog TV is if you have purchased a Digital-to-Analog Set-top Converter Box. Between January 1, 2008, and March 31, 2009, all U.S. households were able to request up to two coupons, worth $40 each, to be used toward the future purchase of eligible digital-to-analog converter boxes. Eligible converter boxes are for the conversion of over-the-air digital television signals, and therefore are not intended for, and will not work on, analog TVs connected to a paid provider such as a cable or satellite TV service.
PLEASE NOTE: When you are shopping for that converter box, make sure it will work with YOUR TV SET! We came across a converter box that would only display its internal menu system on its component or HDMI outputs. That means, if your TV has ONLY an antenna or antenna and analog (NTSC/composite) video inputs, you would not be able to see the converter box's setup menus. Why did they do that?
Confused yet? You're not alone. The bottom line was, you or your TV provider (cable, DSS, FiOS, etc.) MUST HAVE DONE SOMETHING by June 12, 2009. If not, you wouldn't be able to watch television (don't worry - they've already done it). For non-broadcast providers this was a very expensive undertaking - it is likely that some corners were cut. And, the over-the-air broadcasters have already spent a boat-load of money on this, and are budgeted to spend even more!
But we're the winners - we get better pictures, and they will keep on getting better for the foreseeable future. Why? Does anyone remember the grainy B&W TV pictures we watched in the 50's & 60's? Color TV became wide-spread in the 70's, & 80's but the complexity of color meant the pix weren't much better, but at least (some) cable systems were able to deliver TV with less noise and interference. Until digital TV came along, we were still using the exact same system (known in the U.S. as "NTSC") but over time, dramatic improvements were made in the quality of that delivery system. Expect the same of HDTV. For example, bandwidth reduction techniques have already gotten a lot better, and are improving on nearly a daily basis.
Dick
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A footnote on HD-DVD vs. Blu-ray DVD
Warner Bros. Entertainment, which had released movies on both HD-DVD and Blu-ray format discs, said on 1/4/2008 it would drop its support for HD-DVD titles in May.
In announcing its decision, the company said "consumer confusion and indifference toward HD-DVD" has kept the technology from reaching mass adoption and becoming the important revenue stream that it can be for the industry. Kevin Tsujihara, president of the Warner Bros. Home Entertainment Group, said "Consumers have clearly chosen Blu-ray".
A consumer survey released in December, 2007 from The Diffusion Group revealed, however, that among those interested in buying a high-def DVD player, 43 percent expressed a preference for HD-DVD compared to 27 percent who chose Blu-ray. 30 percent were undecided.
The HD-DVD Promotional Group issued a statement late Friday calling the decision a setback for HD-DVD. But Michael Greeson, president and principal analyst for The Diffusion Group, forecasts that the move will have a more dire impact. With Warner going Blu-ray only, Paramount and Dreamworks will likely follow suit, leaving Universal as the only major studio supporting HD-DVD. HD-DVD's lifetime as an HD movie format is now numbered in days, weeks at the most, he said.
Greeson added that the timing of the Warner Bros. announcement is unfortunate for consumers. "It's disappointing that Warner chose to wait until after the Christmas shopping season to make the announcement. They should have declared their allegiance before shoppers spent money on HD-DVD players and discs. That wasn't going to happen, of course, because they wanted to clear their inventory of HD-DVD titles."
References
Federal Communications Commission On June 12, 2009, federal law requires that all full-power television broadcast stations stop broadcasting in analog format and broadcast only in digital format. Here's what these requirements will mean for you and your television viewing.
Advanced Television Systems Committee The Advanced Television Systems Committee, Inc., is an international, non-profit organization developing voluntary standards for digital television. ATSC Digital TV Standards include digital high definition television (HDTV), standard definition television (SDTV), data broadcasting, multichannel surround-sound audio, and interactive television.
Public Broadcasting Service (PBS). PBS and its member stations are very excited about the transition to digital television, which will allow them to bring viewers even more outstanding programming, as well as offer better sound and picture quality.
WGBH Educational Foundation One year from now, the biggest change in broadcasting transmission since the 1953 advent of color TV will take place. And most Americans say they have no idea why, or how it will affect their ability to watch television.
Editor's note: Dick is a (recently) retired professional broadcast engineer with more than 45 years of experience, who has held a First Class (now General Class) Radiotelephone Operator's License (aka GROL) since 1965. One of his primary job functions was design, installation, and maintenance of digital and HD systems and infrastructures. He remains involved in broadcasting on a consulting basis.