Question about Olympics in HD on NBC

[Dbailey]

Shaun, can you give us any news on the HD on the winter olympics this year? I know in 2004, their were problems but i felt it was still pretty good. Just wondering what we can expect from NBC this time. thanks.

[NBC4ENG]

Here is what I know. There will be no time delays between analog coverage and digital coverage. Events will be real time. Same announcers and coverage on SD and HD. All indoor events including figure skating, speed skating, hockey will be full HD with 5.1 surround. Outdoor venues including ski jumping, snow boarding, etc. will be in 16 x 9 SD format converted to 1080i with 5.1 surround.

[NBC4ENG]

One more thing. Go to the NBC 2006 Olympics web site and the program guides are available with event times.

[O2C]

Any chance of shutting down the subchannel during the Olympics?

[NBC4ENG]

WxPlus stays. By the time of the Olympics, our new HD encoders will be in place. You should notice no artifacts in the HD service. If you would like to read about the new encoder technology and its capabilities go to the Harmonic Inc. web site. You will be looking for the MV 450.

[ASDFCommander]

NBC4ENG,

I was wondering if you could tell me a little more about the broadcast chain from NBC to the local stations and then to my TV, as I've always wondered but never had the chance to ask anyone who knew.

I've been enjoying the Olympics on WCMH-DT OTA, but during certain high-motion parts, the picture turns into macro block slurry. Is that just how it comes from the Satellite? If not, is there anything that can be done about it? Like maybe upping the bitrate some more and broadcasting at a more high-motion friendly format such as 720p? Or are you tied to whatever NBC gives you/dictates?

Thanks.

[jpdublin]

I've been enjoying the Olympics on WCMH-DT OTA, but during certain high-motion parts, the picture turns into macro block slurry.



I was wondering what type of television you have. I was watching some of the Olympics at a friends house and noticed on his LCD what you are describing. I have not noticed it on my DLP. That being said, I am not sure if it has something to do with quick motion on certain types of TV's or another issue.

[ASDFCommander]

I have a LCD-TV, but I've been capturing the Olympics on my computer for playback later and can see the blocking on both my computer monitor (CRT) and HDTV.

[Scott]

Weclome to the forum ASDFCommander! What are you using to capture the content, an HDTV capture card or an analog?

[Scott]

I have an LCD/RP, and I too notice some blocking during quick movement. Having said that, the blocking is on where near as bad as it used to be before the new encoder chain. At times, I'll flip to the NBC national HD feed to compare--and it is unwatchable compared to the new WCMH-DT OTA broadcast.

[Robbiee19]

I have a great picture so far. But I have a Samsung 61" DLP. NBC National HD feed on D* come's close, but not as good as the OTA. Watching the down hillers was great with no blocking during quick movement.

[ASDFCommander]

Weclome to the forum ASDFCommander! What are you using to capture the content, an HDTV capture card or an analog?

I capture the ATSC streams directly (w/o any recompression) with a HDTV tuner/capture card.

At times, I'll flip to the NBC national HD feed to compare--and it is unwatchable compared to the new WCMH-DT OTA broadcast.

Yeah, I've heard sat HD is only like 7-10Mb/s, at that bitrate I'd rather just watch SD.

[NBC4ENG]

To clarify some issues. The HD bitrate at WCMH can go as high as 18.2 MBits/sec. On the average, the actual bitrate I am seeing is 17.2 to 17.9 Mbits/sec. Statistical multiplexing is used to control the the digital stream. If the HD channel needs extra bandwidth, it will be taken from null packets that are available or WXPlus. This is an automatic function and is calculated by the multiplexer.

1080i is the format that NBC has adopted. ABC is the only network I know that uses 720p. The HD signal comes to us by satellite. You are viewing the NBC signal with the latest and greatest encoders and multiplexers that are available. The new equipment was installed especially for the Olympics. Final tweaking, at this facility, was still going on just hours before the start of the big show. The broadcast path here, is as transparent to the network as we can make it.

On the AVS Forum, an engineer who is at the venues has a blog about the way things are done. In addition an engineer from Dolby explains how the audio chain works. Interesting reading. He'll take technical questions from you.

[ASDFCommander]

Thanks, that was very informative.

[nakedeye]

fyi fox is also 720p, although many fox sport nets are 1080i

[zelig2]

I highly recommend checking out the weblog of the engineer over in Torino. Lots of great pictures and information.

http://hdolympics.blogspot.com/

[jdcbomb]

so far i've enjoyed the NBC coverage immensely.

however, i believe it was the 2nd night or 3rd night...i kept getting audio and video dropouts, even though i had nearly 100 percent signal strength...it occurred nearly every 2 seconds and became unwatchable.

also, is there any way to boost the audio of the torino feed...because the local commercials keep scaring the heck out of me whenever they come on during the olympic coverage...i'm actually surprised how SOFT the audio seems to be whenever the olympic events are on.

anyone else experience this?

[Robbiee19]

Yes I have the same problem too. I have to mute the audio when the commercials come.

[Philster]

Same Olympics audio and video problems here. I'm on TW cable.

[NBC4ENG]

If you'll read through the AVS Forum you'll find the same complaints about the audio level from all over the U.S. In a digital system, there are no knobs to tweak for audio. The HD stream is completely seperate from the upconconverted local stuff. It is sent to us in a digital stream and passed through without tampering too much with it. The Dolby encoders at our place take two digital audio streams, create the 5.1 and send it along.

In the analog world, we have active processing that can expand or compress the audio to maintain an some kind of an average. Digital has no processing equipment that can replicate the analog processing. I have looked for and haven't found anything yet. I am at the mercy of the program originator. This is controlled in New York before the final delivery. The engineers at the Olympics have made the call on the dynamics of the audio and think it is fine. Sorry for the discrepency in the levels. And no we can't pull the local levels down. They go through the same Dolby encoder as the HD stream.

[DublinDoodah]

Thanks for the explanation. I've often wondered why the audio levels aren't controlled any better. It's disappointing to learn that as we "improve" technology, we lose functionality. Seems like a serious oversight.

BTW: During the NASCAR race yesterday, the volume of the commercials seemed to be pretty consistent with the race volume ... except the WCMH news promos. They were MUCH louder.