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Discussion Starter · #1 ·
I just watched the NFL pre-game show on NBC. I have used OTA before to get HD, and today is the first time I'm using cable. I'm using a Series 3 with SA CableCARDs.

The show looked AWFUL. Seriously, it seemed like it was some sort of higher-res version of a youtube video. EVERY transition, smoke, flashing light etc during the show was pixelated. Just simple panning over the cheerleaders made the glitter on them pixelated. It looked horrible.

It could just be that this was very motion intense, which it was... but still, I have a hard time believing I would have not seen something like this before on OTA.

So I looked at the file size. It's 2.82GB, for 30 minutes of video. What bitrate does that equal? It seems REALLY small to get 1920*1080 (since it's NBC) at 5.64GB/hour. The only conclusion I can draw is that TWC is compressing the signal so much that it comes out like crap. Or is there another reason?

This was so freaking awful I am inclined to drop HD altogether. I prefer the unpixelated less detailed analog images!

This is the first thing I've watched in HD so far after getting the CCs... maybe I should hold my horses, I guess it could have been a fluke. I'll see if the game itself, or other shows look better...
 

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Discussion Starter · #3 ·
I have no OTA available anymore unfortunately.

12.8 seems like it falls way short of the theoretical capacity? Isn't it 19.x something MBps?

I haven't watched any live sports on NBC except golf before, which is way less motion intensive... that looked fine OTA, as did Heroes, The Office and My Name Is Earl. I guess I'll have to record those and see how they look on cable next week or whenever they start.

"Grey's Anatomy" on ABC looks good right now on cable. Maybe it is just the NBC broadcast...
 

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Discussion Starter · #5 ·
The game itself looks like poor too, IMO. Faces during motion-intensive closeup have lots of pixelation, as does the field and the mesh-parts of the shirts.

If this was my first exposure to HD, I'd be one of those who just didn't see the big deal.
 

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Discussion Starter · #6 ·
I just looked at the Grey's Anatomy recording, it is 2.34GB over 26 minutes. So that would be about the same bitrate, but resolution on that one is 1280*720. Maybe that explains why it looks better?
 

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Discussion Starter · #9 ·
bkdtv, thanks for your input.

I just checked 4 OTA recordings of "The Tonight Show" from the NBC affiliate in Tucson, AZ. They range in size from 7.90 to 7.94 GB. That would give a bitrate of roughly 17.44 Mbps (they are 62 minutes long).

I will record "The Tonight Show" tonight off of TWC here in San Antonio. Even though they are from different broadcast markets, I assume that the OTA/cable comparison should still be valid?
 

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Discussion Starter · #11 ·
bkdtv, thanks again for your information.

I recorded The Tonight Show off of TWC cable in San Antonio, and the size was 5.89GB. So the bitrate on cable here is 12.97 Mbps, compared to the 17.44 Mbps I had OTA in Tucson.

I checked one scene in the opening credits, where the camera quickly pans across a TV. It is a noticeable difference between the OTA recording and the cable recording there - the OTA recording displays no artifacts, but the cable recording does.

I think it's pretty safe to say that my cable company is compressing the signal too much and that it is what is causing this lousy PQ (probably in combination with other factors when it came to the NFL game). I can't imagine that 12.97 Mbps will be enough to even show artifact-free regular programming in 1920*1080?

Does anyone think that it's worth trying to talk to anyone at TWC regarding this? I mean, obviously they know what they are doing, I guess they just figure most people don't have less compressed OTA to compare to, and will accept this crap.
 

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Discussion Starter · #13 ·
bkdtv said:
I don't suppose Verizon FiOS is available in your area? They don't touch the OTA signal (i.e. identical to off-air bitrate).

If you are able to receive channels OTA, I would set your season passes to use those channels instead.
Nope, no FiOS - only TWC.

I am watching golf right now on NBC. It looks as awful as the football did, and it never looked this bad OTA in Tucson. Steve Stricker's red shirt is all pixelated when he's walking down the course. This is bad.

I think I'm just going to buy a DB4 antenna and mount on the wall behind the TV and hope that'll do it (can't receive OTA with my old antenna here, that's why I decided to try cable). Will save me a few bucks per month too. I'm going to write an email to TWC now too.

I understand people who just don't see the big deal about HDTV, if this is what they're used to. :) I didn't understand it until I had OTA at my house - up until then I had only seen poorly calibrated TV displays in the stores.
 

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Discussion Starter · #14 ·
I keep bringing this up... :)

I recorded 1 NFL game on Fox today, 1 on NBC, and the PGA tournament on NBC.

Bitrate at NBC was just under 13 Mbps for both broadcasts, and on Fox it was just over 13 Mbps.

The NBC broadcasts both looked pretty crappy. LOTS of artifacts again, and generally unpleasant to look at as soon as there was motion.

The NFL game on Fox looked very good - few if any motion artifacts of the kind I saw on NBCs broadcasts. They broadcast in720p. Does the fact that they broadcast in 720p vs 1080i on NBC create less artifacts at around the same bitrate? I'm starting to doubt that the lower bitrate is the only thing that's wrong with the NBC broadcasts...
 

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Discussion Starter · #22 ·
I just sent an email to NBC Sports complaining about this, as it seems more and more like an issue on their end rather than only with the bitrate. Unfortunately, the email was bumped back saying it couldn't be delivered. No idea why, but I'll try again.
 

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Discussion Starter · #25 ·
I just watched "The Office" on cable... my God, it looked horrible. I have watched it OTA before and never had any issues with the quality. This was a disaster. EVERY quick zoom or pan with the camera led to horrible artifacts. It looked like mosaic in some cases. 12.7 Mbps bitrate.

I will call TWC tomorrow and complain... not that it will help much. I emailed them before but didn't hear anything, I emailed NBC too but my email was returned.

Didn't end up ordering the antenna because of the convenience of cable... but "Heroes" will look like crap here too, and I really would like that to be in good quality.
 

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Discussion Starter · #26 ·
I was corresponding with the local NBC affiliate, and asked about this. Here's the reply:
We broadcast the HD signal straight out the receiver from NBC. Our encoder for the Mpeg stream is set for about 12 Mbps. We also have 4.2 and room for 4.3 in our stream hence the setting for about 12. Time Warner gets our signal over the air and I don't know what they do to it after that. They may compress it even more I'm not sure. I'll try to find out more. I watch us over the air at my house and I don't notice artifacts on a plazma screen with true HD programming. I do see artifacts on non-HD material.
12 MBps seems really low for OTA, even if they do have one subchannel in use. I can't argue with him yet though, as I haven't seen the OTA broadcast here...
Would TWC be doing something else with the signal that could cause the problems? Maybe something like constant bitrate versus variable bit rate (not sure if that is relevant here)?
 

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Discussion Starter · #28 ·
He told you that their station encoder is set to 12Mbps. That is barely adequate for series programming, and completely inadequate for 1080i video like sports.

As I noted in my previous post, the NBC network feed sent to every affiliate is about 24Mbps. At least 16Mbps is needed to produce an acceptable picture on most NBC sports broadcasts, and 17+Mbps is preferred. At 12Mbps, 1080i sports will look like garbage.
Do you think there's any "higher up" I could contact here? Does NBC have some guidelines for their stations? I find it odd that the Tucson, AZ station had a ~17Mps bitrate and the San Antonio, TX station has such a low bitrate. Looks like I can't blame this on the cable company after all.
 

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Discussion Starter · #31 ·
Thanks for that information.

I guess I will respond and ask why they have the encoder set to such a low bitrate (although I can guess the answer). I wonder if the guy is not watching at the right distance. I view at just over the SMPTE recommended distance for HD (about 6 feet for my 42" screen) to take advantage of the full resolution, which is closer than most people. Obviously, these defects are a lot easier to spot then, but on most material this issue is nonexistent.
 

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Discussion Starter · #33 ·
Unfortunately, most broadcast stations still use small screens (typically under 20") to monitor their signals.

If you are able to talk to the engineer on the phone, you might invite him (and the station manager) to visit your house to see the quality of their high-definition sports broadcast on a larger screen.
He says in the email that he watches it at his house on a "plazma" (sic) screen, so I assume he's got the right size. I also assume that he sits too far away to notice this at the level that I do. If I sit 15 feet away, this is much less noticeable (of course). I wonder if taking a snippet of it and showing him (I have it on the PC in uncompressed form) would do any good.

OT: I honestly don't understand why some people even have HD, they sit so far away from their screens that the improvement in resolution is almost negligible.
 

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Discussion Starter · #37 ·
I hate to say this, but I've noticed the same thing since getting my S3.

I was using an SA 8300HD prior to the S3. While I hated the SA box's interface, my recollection is that the picture quality is somewhat better with HD programming, ESPECIALLY at times of rapid motion.

On the other hand, my S2 replaces a ReplayTV 5504. The S2's image quality at "high" or "best" settings is slightly better than that of the ReplayTV at it's "high" setting.

Does anyone here have a similar experience in comparing a cable company DVR to the S3?
At my previous house I had a different cable provider, but I noticed no difference when going from the SA 8300HD to the Series 3. I also have no other issues with motion other than on my local NBC affiliate (HDNet Movies for example, which I believe is also 1080i, looks great).
 

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Discussion Starter · #42 ·
Just to give an idea what it looks like at my end... here are two screenshots from tonight's "My name is Earl" (click to see higher resolution).

The one that looks like crap is while the camera pans up. Notice that even the channel bug gets pixelated!

The one that looks fine is when the camera stopped panning. This is how it is for virtually every shot that pans, especially if it's lot's of color for some reason - NFL games look like crap.

I think I might send these screenshots in my e-mail to the guy at the local NBC affiliate...



 
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