Check out Best Buy or Circuit City or Fry’s – whatever floats your boat – and you’ll see HDTV rocks. Lower prices and more things to watch are driving consumers to shell out beaucoup bucks for new advanced viewing devices.
So far, the big three – cable, satellite and video’s baby toe, IPTV – are selling HD based on how many channels they can offer. As more overpaid professional installers wire HD sets into home entertainment centers, though, the number of channels coming through to those sets won’t be enough; the quality of those channels will decide whether those high-end subs are happy with the service they’re getting or take their big bucks to the other guy.
This is a scenario that should send shivers through some overly compressive providers, said Per Lindgren, vice president of business development for Net Insight, a company aimed at improving network QoS and enhancing the end viewing experience.
Poor signal quality shows up in several annoying ways on HD sets. The most irksome is pixelization where the picture breaks into a thousand puzzle pieces then reassembles itself right before the angry viewer’s eyes. An offshoot is audio dropout or distortion, more apparent with high-end sets connected to entertainment systems, and the least apparent for now is the one that will become a deciding factor in choosing cable over satellite or IPTV over cable: the robustness of the picture. Finding the source While the picture could start to degrade the minute it leaves the broadcast source, problems more likely begin somewhere between the headend and the end user, said Lindgren. Most times they happen because the service provider – and haven’t we all heard this tune sung before? – is over-compressing the content.
Lindgren believes that HD will be transmitted via IP although it won’t necessarily arrive at the end user’s HDTV in that format. While appropriate for data, voice and SD video transport, HD can be a problem because "when you start to do networking with a lot of video in it (and HD is nothing if not bandwidth consumptive), it starts to get harder, and current networks are not really suitable for it," Lindgren said.
The first solution – the proper use of that term as an answer to a problem – is to prioritize traffic. But which traffic?
"If you use prioritization, everything is going to have high priority – or at least a majority of the traffic," said Lindgren. "This is really an issue when you start scaling up the IPTV and the cable TV networks."
So far pure IPTV – the stuff that AT&T is delivering – is so new with so few subscribers that it’s getting a free pass in the quality war. That won’t continue, Lindgren predicted, because IPTV subscriber numbers will ramp up about the same time that TV goes from SD to HD. At that point, service providers can pretty much scrap copper or DSL and go straight fiber-to-the-home, he said.
Net Insight’s goal – and its moneymaking reason to exist – is to help all manner of carriers deliver good quality HDTV at least out to the nodes or DSLAMs. From there, if a carrier uses some form of switched video to deliver streams to consumers, there shouldn’t be a problem, he said. Quality goes in before … "We’re trying to promote a solution (that will be showcased at next month’s NAB) that is more QoS-enabled" by separating the HD video from the rest of the content running across the IP link, Lindgren said.
"You can do it on a wavelength basis, but it tends to get very expensive, and you need to build a very powerful network," he said. Net Insight has sub lambdas, "which set up a dedicated path to separate the different services on different sub lambda channels. From an IP perspective, it’s really point-to-point from the content all the way out to the DSLAM or cable hub."
From there, it’s just a matter of keeping the signal clean to the end user, generally by using some form of switched digital transport, he said.
"The last mile is more deterministic," he said. "It depends on where the operators are in their buildout and what last mile technology they have chosen in combination with what type of network they are using behind that." Nobody’s leading There are, right now, no clear quality leaders, said Lindgren, refusing to select cable, satellite or IPTV as providing the ultimate HD viewing experience.
"Satellite has the advantage that they can already do it today and have a big distribution set, but of course they are limited in spectrum, and they sometimes take a chance to do more compression, and that impacts the quality of service," he said. "You have IPTV over DSL, you have IPTV over fiber-to-the-home, so it depends on the network and their last mile, so you can’t just say, ‘If it’s IPTV, it’s going to be better than cable.’ Cable is also coming out with a next generation DOCSIS 3.0, and a lot of MSOs are looking at providing HD over the IP over DOCSIS, and that will help them provide more channels and more HD content."
Then there’s MPEG-4 which "will help" because it lets providers do more channels of HD by raising compression rates available from MPEG-2.
The thing is, consumers are going to the stores in record numbers to buy the HDTV experience, and if Comcast or Cox doesn’t deliver the best quality and Verizon or AT&T does, those viewers will pixelate and reappear on someone else’s subscriber list.
"Right now, everybody is proud to offer HD. For the end user, if you do get pixelization or bad audio, you’re going to ask your neighbors if they have the same problem. At that point, very quickly it will turn into selling arguments for the operators that can actually provide quality of service," he concluded. – Jim Barthold