A Lot of Prayer and a Little Luck

TV Technology-Europe Editor Mark Hallinger caught up with Dave Mazza, Senior Vice President of Engineering for NBC Olympics a few hours before closing ceremonies.

TV TECHNOLOGY: What was your biggest concern going in?

(click thumbnail)Dave Mazza, Senior Vice President of Engineering for NBC OlympicsMAZZA: I think the impact of doing this much HD on this grand a scale with this many people and this much equipment all spread around the city and the countryside. We were all lacking HD experience... a lot of people have it back in the states on individual shows, but my whole group didn't have as much HD experience as I would have liked just because we hadn't done an Olympics yet, fully in HD. We did two Games prior to this in HD but that was really just minimal coverage. So to do the level of production that we do, which is very high, to do that and not set people back a number of steps was probably our biggest worry.

We also had the worry that some of the HD equipment wouldn't play well together, and as it turned out, that is what plagued us mostly. I think SD and especially serial digital over the years had gotten so easy... we were an early adopter of embedded audio and once you figured that out it made it even easier to move a signal around and not have to be fighting with levels and phase and missing channels and legs and such.

Because SD had gotten so easy our timelines and all of our set-up time and manpower schedules were all built around that, and over the three or so Games that we had done serial digital we had shortened and shortened and optimized the timelines further and further... not fully realizing when we went to do the HD how much we had shortened them. When all of a sudden it isn't plug-and-play and the stuff didn't turn on as easily as SD, there was far more head scratching and troubleshooting of technical interoperability issues.

TV TECHNOLOGY:And the aspect ratio issues you had feared?

MAZZA: Going in I had thought we were going to spend a lot of time chasing our tail on aspect ratio issues, but we spent almost none. The multiformat dub area was a rats nest of aspect ratios and the guys there would lament that it would take 30 to 40 minutes to set up a dub due to the complexity. But aspect ratio became second nature, you had to pay attention to it but it was not hard.

TV TECHNOLOGY:Any other picture hits?

MAZZA: We were pleasantly surprised with the compression artifacts caused by the converters. We certainly had macroblocking and pixelization, but it was not as bad as it was in Athens. We had tried hard to do what we could, but the ATSC compression and the 50 Hz to 60 Hz converter were unchangeable really, even in the past year and a half we couldn't change either of those variables. So we did what we could with the equipment around them and I was pleased it looked as good as it did.

I was quite pleased with the SD upconversion, the 16:9 anamorphic upconversion looked better than I thought it was going to look. You actually could fool some people within the plant on whether it was an SD or an HD venue... on a smaller monitor. When you got to the big 50- or 60-inch monitors, especially on the wide shots where you would normally see a lot of detail, you could see the difference.

TV TECHNOLOGY: There were some problems with surround audio, which could not be heard in Torino or Athens, but only at the stations or the home receiver.

MAZZA: It turned out to be the fact that with the distribution encoders and decoders within the network, the different pairs of audio channels cannot be guaranteed to be time-aligned. When you put similar audio across different pairs of channels, as we were trying for the first time, the similar audio then causes a flanging effect.

TV TECHNOLOGY:Overall, what pleases you the most?

MAZZA: On the technical side I think the viewing experience was way over 100 percent compared to the SD experience. If you were an HD viewer at home sitting there watching the Games in HD night in and night out, I would hope you were very pleased with the fact that most of the venues were in HD, and the ones that weren't were at least in the right aspect ratio. All of the NBC-generated elements were HD. I would hope that the HD viewers--maybe you can't call them early adopters anymore--were pleased with that.

TV TECHNOLOGY:Did you look on the Web much for comments from back home?

MAZZA: I looked a lot the first week... the roughest week. When I saw the Web guys starting to complain about the NBC bug, and then 'how could NBC let the ski jumpers wear those uniforms where the colors didn't look good in HD...' I thought OK, if they're accusing us of picking the wardrobes for the athletes, well... and when I saw them down to complaining about the position of the bug or the way the bug looked, I thought 'if this is what we're down to I'm happy... the picture's good.'

TV TECHNOLOGY:On the subject of balancing concerns for the SD audience while encouraging the next step, HDTV, what do you think broadcasters can learn from this?

MAZZA: Anybody in this plant, who's been walking around looking at the HD images on these big 50-inch screens is going to say 'I gotta have one.' They occasionally see it at Circuit City or wherever at home, of questionable quality with TV sets adjusted to the max contrast and looking bad, but here they saw it for real.

For our limited little group of audience members right here, all 2,850 of us, I think everybody wants an HD set now. I think that's a telling thing. Granted, we all work in the industry, but in some cases those who don't are even more awed by the picture than we are because we are used to looking at the good images. When the public truly sees what it looks like, and the prices continue to fall, I think you will find people will adopt fairly quickly.

The other thing I would say is about archives in general, because we have a lot of archive material. We made a decision a while back that there was no reason to convert it all to HD in the case that you might use it. Just do it on the fly... we did it on the fly and the Sony tape machines worked perfectly well... the upconverters in the tape machines looked great and we did this outside of the Avids as well, because the Avids take time to transcode on an upconvert or a downconvert. Even an Avid that was finishing a piece in SD for someone, like with our edit-at-home project, in some cases we found it was easier to record out to HD, and then play the tape with the SD output of the VTR.

If I was converting a smaller or mid-sized TV station, I think when I made the switch, other than taking a few baby steps to test and make sure you know what you're getting into, I would consider the wholesale changeover. Not to say you won't continue to play your SD archives in SD, but shoot your live shots in 16:9 SD and upconvert them when they land at the plant. The 16:9 SD stuff that had stayed digital and never went to composite, it looked really good.

So whether it's your studios or your remotes, pick which one goes first, if you do the studios first, and your remotes or ENG liveshots are SD, do them 16:9 and up-rez them. It's not hard. The frame syncs and the processing packs that we used from Miranda have every one of those settings--you can up-, down- or crossconvert or change the aspect ratio. Normalize it when it gets to the plant, and try to keep the plant consistent, except in the dub rack.

TV TECHNOLOGY:What about HD transmission issues and encoding?

MAZZA: Tandberg was huge for us this time. I think we had over 250 Tandberg units, encoders and decoders, on both ends. We did some pretty slick things with them. From Daily Medals we moved four 16:9 anamorphic cameras at about 40 Mbps, on a single VANDA.

From the skating practice rink, the images when Michelle Kwan fell in practice, that was shot by our three HD cameras at the practice rink, which went through three Tandbergs that got muxed onto a single 155 Mbps OC-3 circuit on an RF link with a double hop into the figure skating compound. One year ago, most people were saying moving HD on RF was too difficult. But we had three cameras moving on that OC-3 link. It was bounced off a dish up on the mountain above the city and bounced back down into the figure skating compound.

TV TECHNOLOGY: IP in general was used in a few applications, comms, and some video and machine control. How'd it work and what are the benefits?

MAZZA: It's a brave new world of IP and it scares the pants off most broadcasters. We moved most of our comms circuits, and 2/3 of our phones over to IP. We had a lot of other computer data going, some video was going over IP, camera control, router control... all sorts of things.

It's a unifying concept--once you get it to an IP-based thing you plug it into a router and if you're nice to the IT guy it comes out on the other end. It was great. It's just a bit scary for a broadcaster who was not brought up as an IT-based person. To everybody's credit here our IT guys--and our broadcast-saavy guys--worked hard to meld the two philosophies. It's everything from the philosophy of cabling to power redundancy to equipment redundancy and diversity. There are a lot of things as more broadcast stuff migrates to IP- and IT-based workflows that the two different groups of experts have to get together on.

We've made great strides, but for example, one night the comms to hockey was garbled, packets were being dropped on the E1 circuit, a 2 Mbps circuit to hockey. We looked around and one of the graphics guys was transferring a 250 MB file to hockey. The QOS in the router was supposed to be set so that the comms circuits got the highest priority. But something was not working right and the graphics transfer was stepping on the comms. Who would have thought that a graphics transfer was now interrelated to a comms problem?

TV TECHNOLOGY:In terms of difficulty, how did these Games rate compared to others?

MAZZA: I had hoped coming out of Athens that that effort would have been our hardest Games. Not that I don't like a good challenge, I do or I wouldn't be doing this. Athens was really hard, but we knew all of the technology and techniques that we were using there, even though we pioneered a lot of new little production techniques. The hard thing in Athens was keeping that many shows on the air at the same time.

Torino was harder. We weren't doing that many shows at the same time, but with the conversion to HD there were so many issues that were happening in the transmission chains and the signal chains that were mysterious. Instead of simply the hard work it took in Athens, Torino involved a lot of prayer and a little luck because there are issues that no one understood, until this day.

Mark Hallinger