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post #661 of 2079
4/2/08 at 11:51am
Quote:
Originally Posted by davehancock View Post

No, what I am saying is that SciFi sends a 45mbps signal.

And just where/how are they doing that?

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post #662 of 2079
4/2/08 at 11:52am
Quote:
Originally Posted by davehancock View Post

Yep, that's (more or less) what I'm talking about. Now that you mention 45mbps, I think that may be the right number.

No, what I am saying is that SciFi sends a 45mbps signal.

You're completely wrong. ABC, CBS, and CW send a ~45Mbit/s feed and NBC sends ~22Mbit/s. Cable channels are fed at ready-to-air bitrates ranging from the ~12 seen on UHD to the ~14 on HBO to the 17-18 seen on ESPN, HDNet, and HD Theatre. It's no coincidence that those final 3 are frequently cited as having the best PQ.
post #663 of 2079
4/2/08 at 11:59am
From a post by KenAF at DSLReports. It doesn't address the cablenets, but does outline the major broadcast nets.

Quote:
Verizon FiOS gets most of their locals via fiber feeds from the local affiliate; when a fiber feed is not available, they use OTA, as suggested above. Verizon does not have a direct fiber feed to ABC/CBS/FOX/NBC. The quality of the feed from your local affiliate is nothing like the quality delivered by ABC/CBS/FOX/NBC to the local affiliate.

Do not confuse the Mbps listed in the MPEG-2 header with the actual program bitrate. In many cases, that header set at the backhaul is never changed to reflect the bitrate used for satellite uplink (or 8VSB transmission).

(1) FOX takes its 1.0Gbps (uncompressed) 720p truck feed, compresses it down to 73Mbps or less for their operations center, and then uplinks it to satellite at 14.6Mbps for distribution to local affiliates.

FOX affiliates pass this feed through without any extra processing or compression using specialized equipment provided by FOX.

(2) CBS takes a 1.5Gbps (uncompressed) 1080i truck feed, compresses it down to 45Mbps for their operations center, and then uplinks it to satellite at 45Mbps for distribution to affiliates.

CBS affiliates process and re-compress this 45Mbps feed to 19.4Mbps or less. Some CBS affiliates have newer/better encoders than others.

(3) ABC takes a 1Gbps (uncompressed) 720p feed at the truck, compresses it down to 45Mbps for their operations center, and then uplinks it to satellite at 40Mbps for distribution to affiliates.

ABC affiliates process and re-compress this 40Mbps feed to 19.4Mbps or less. Some ABC affiliates have newer/better encoders than others.

(4) NBC takes a 1.5Gbps (uncompressed) 1080i feed at the truck, compresses it down to ~38Mbps for their operations center, which then recompresses and uplinks it to satellite at 24Mbps for distribution to affiliates.

NBC affiliates process and re-compress this 24Mbps feed to 19.4Mbps or less. Some NBC affiliates have newer/better encoders than others, and since NBC was the first network to launch with high-def, a number of affiliates are still using [outdated] early generation encoders.

The higher the quality of the source, the better the result with compression. Because NBC distributes its feeds at lower bitrates, more bandwidth is needed to produce a comparable picture to say, CBS. Unfortunately, they rarely get it and quality suffers as a result.

The source network feeds do not have any local commercials. They have a black screen or network logo where the local commercials would be. ABC, CBS, and NBC do not allow any providers to distribute the source feeds without local commercials; if they did, picture quality on each would insanely good.
post #664 of 2079
4/2/08 at 12:02pm
Quote:
Originally Posted by NetworkTV View Post

No, when it's broadcast, those repeat frames count as video information. Once it's sent out at 60fps, you get 60fps. Not only that, the networks aren't playing back film - they're playing back video tape at their broadcast frame rate. The original source material is irrelevent for this test.

It's completely relevant. Those frames may not be pure duplicates according to MPEG2 repeat flags, but 99% identical frames take very little bitrate to encode. With a good encoder employing duplicate detection, 24p content in 720p takes about 60% of the bitrate of 24p content in 1080i.
post #665 of 2079
4/2/08 at 12:02pm
Quote:
Originally Posted by coyoteaz View Post

You're completely wrong. ABC, CBS, and CW send a ~45Mbit/s feed and NBC sends ~22Mbit/s. Cable channels are fed at ready-to-air bitrates ranging from the ~12 seen on UHD to the ~14 on HBO to the 17-18 seen on ESPN, HDNet, and HD Theatre. It's no coincidence that those final 3 are frequently cited as having the best PQ.

I recall reading that about NBC/Uni cable channels, in fact IIRC, they pack even more signals than "normal" on a transponder which makes the great PQ on SciFi-HD from DirecTV even more amazing.
post #666 of 2079
4/2/08 at 12:09pm
Quote:
Originally Posted by keenan View Post

From a post by KenAF at DSLReports. It doesn't address the cablenets, but does outline the major broadcast nets.

The source network feeds do not have any local commercials. They have a black screen or network logo where the local commercials would be.


Not strictly true. ABC sends out PSAs during local break time. CBS and The CW do indeed do black. NBC probably does their animated logo thing (which they do for SD). Don't know what Fox does these days, though I suspect they are doing their logo as well. So, ABC is the only one that doesn't fit the mold
post #667 of 2079
4/2/08 at 12:32pm
Quote:
Originally Posted by bfdtv View Post

The Matrix shots were taken in VideoRedo because I am having an issue with 720p captures in MPC w/ Dscaler5. I've updated the Matrix post to reflect that.

Yea, dscaler has issues with 720p, although they look much better than videoredo besides the lines. You could try ffdshow or the internal MPC mpeg2 decoder.
post #668 of 2079
4/2/08 at 12:33pm
Quote:
Originally Posted by bfdtv View Post

....Based on your comments, I recorded several programs from HGTV. Last night, I briefly looked at Over Your Head: Artistic Bathroom.

The recordings from both providers were horrific during motion. Perhaps the FiOS feed was slightly less horrific on some motion, but most of the time, they looked equally bad to me. I can't speak to issues on other HGTV programs, but at least on this series, you cannot blame Comcast. It looks to be a production / source issue.

Ahhh, thanks for the perspective. That sure helps whole bunches. Perhaps I need to "relax" for a while, and redirect my focus onto HDTV HD itself. I think "horrific" sounds right in the same ballpark I've been seeing....

Thanks again, and for all of your efforts here!
post #669 of 2079
4/2/08 at 1:07pm
Quote:
Originally Posted by keenan View Post

I recall reading that about NBC/Uni cable channels, in fact IIRC, they pack even more signals than "normal" on a transponder which makes the great PQ on SciFi-HD from DirecTV even more amazing.

It is quite possible that D* gets the NBC/Universal stuff via direct fiber. Someone else that knows for sure will have to answer that question.

But, there is a NBC/Universal HD satellite transponder that has three streams on it, containing Brave East, USA Network East and Sci-Fi Channel East. Based on QPSK mux rates, the bitrate per stream would not be very good. But, in this case, 8PSK is being used. The total mux payload bitrate is approximately 62.2 Mbps. On average, each stream would be about 20 Mbps (after mux payload overhead and audio streams). Obviously, with a stat mux, what each video stream can get will depend on the needs of the other streams.

For best re-encoding of MPEG-2 to MPEG-2, the original MPEG-2 needs to have a bitrate that is two times higher than the new MPEG-2 bitrate. This means that the bitrate being used on the transponder is technically not good enough for re-encoding. They would have to use the highest FEC value (8/9) in order to get the highest mux bitrate of 73.7 Mbps. But that is tough to receive (just ask Fox what they had to go through). Even then, it would limit the number of video streams to two, in order to come close to the 2:1 re-encoding ratio.

I'd love to get what they are sending up on the bird, as it would definitely be a lot better than what cable is doing to the MPEG-2 quality, especially Comcast. But even that won't solve the screen clutter problem
post #670 of 2079
4/2/08 at 1:17pm
Quote:
Originally Posted by HIPAR View Post

I still contend you need to be a hypercritical enthusiast (as most here are) to get into a huff about the differences in those latest images. If you go back to those images posted at the beginning of the discussion, there is a 'clear' difference between the two services. Where did all those really ugly macroblocks go? Has Comcast managed to get things adjusted to work better?

--- CHAS

the nasty macroblocking has improved (to an extent). Dropped frames are still a big issue. I'd had to turn off some movies on USA because the random slow motion makes it quite annoying.
post #671 of 2079
4/2/08 at 1:17pm
Quote:
Originally Posted by coyoteaz View Post

With a good encoder employing duplicate detection, 24p content in 720p takes about 60% of the bitrate of 24p content in 1080i.

If 720p takes so few bits, then what could possibly be in ABC's 40 Mbps 720p feed?
post #672 of 2079
4/2/08 at 1:20pm
Quote:
Originally Posted by keenan View Post

I recall reading that about NBC/Uni cable channels, in fact IIRC, they pack even more signals than "normal" on a transponder...

The NBC/Universal SD mux containing Sci-Fi East/West is not packed tight. The mux transport is 40.61 Mbps and only contains four active video streams and a static NBCU card. For SD video, even if 4:2:2, the bitrate they are allocating is damn good.

Is there a specific NBCU cable channel that was referenced in what you were reading that was supposedly packed with lots of other channels?
post #673 of 2079
4/2/08 at 1:24pm
Quote:
Originally Posted by scowl View Post

If 720p takes so few bits, then what could possibly be in ABC's 40 Mbps 720p feed?

The 2:1 ratio needed for the best re-encoding to a lower bitrate.

NBC violates that "rule" with their network HD feed.
post #674 of 2079
4/2/08 at 2:04pm
Quote:
Originally Posted by mrvideo View Post

Not strictly true. ABC sends out PSAs during local break time. CBS and The CW do indeed do black. NBC probably does their animated logo thing (which they do for SD). Don't know what Fox does these days, though I suspect they are doing their logo as well. So, ABC is the only one that doesn't fit the mold

Sort of. ABC only sends out PSAs during certain breaks, namely during the morning programming and during the 10:45PM local cover break. The rest of the time, they vamp out the last national promo with a freeze, go to black, then send out color bars. You don't want to fail to roll your local break over those...
post #675 of 2079
4/2/08 at 2:25pm
From the Consumerist, maybe it should be filed under "Believe it or Not"


Comcast Spews BS When You Complain About HD Degradation

David wanted a straight answer from Comcast as to whether they were degrading his HD signal, but instead was fed a colossal trough of baloney. The executive customer service rep who replied to David's email said Comcast is using a "new system" for HD and while it "works well with clean 1080i signals, we're making some adjustments to improve how it handles other types of HD signals so we can bring you the best HD picture. We apologize this has not created the HD experience that we intended, but we will work towards getting it right. "Sure... check out this previous post, Comcast Degrades HD Quality To Make Room For More Channels, for the science and proof of how Comcast (and other cable operators) are degrading HD feeds to make more money.

Balance of article at:
http://consumerist.com/375341/comcas...hd-degradation
post #676 of 2079
4/2/08 at 2:27pm
Quote:
Originally Posted by mrvideo View Post

The NBC/Universal SD mux containing Sci-Fi East/West is not packed tight. The mux transport is 40.61 Mbps and only contains four active video streams and a static NBCU card. For SD video, even if 4:2:2, the bitrate they are allocating is damn good.

Is there a specific NBCU cable channel that was referenced in what you were reading that was supposedly packed with lots of other channels?

I don't recall, it's been a few years since it was discussed here and of course things may have changed.

It may have been SciFi-SD, USA-SD, MSNBC, Bravo and a few others all on one TP, as I say, I don't remember the details.

In anycase, SciFi-HD looks great on D*, been hoping to get SciFi-HD on my Comcast system to do a direct "eyeball" comparison, but, it's April 2008 in my city of 70K plus Comcast subs and we still only have a total of 11 HD channels.
post #677 of 2079
4/2/08 at 2:39pm
Quote:
Originally Posted by NetworkTV View Post

Sort of. ABC only sends out PSAs during certain breaks, namely during the morning programming and during the 10:45PM local cover break. The rest of the time, they vamp out the last national promo with a freeze, go to black, then send out color bars. You don't want to fail to roll your local break over those...

I've never seen color bars during ABC network primetime. All local breaks either had ABC network promos or PSAs (some network promos are allowed to be replaced by local material). Nor have I seen blacks that last longer than a few seconds. Never seen promo freezes either.

Our local affiliate dumps the promos after the end of the last program of the night. Since that little bit of black is so short, it can look awful when they dump net and go to news.
post #678 of 2079
4/2/08 at 3:30pm
Quote:
Originally Posted by DoubleDAZ View Post

I made my comment vague because I don't know if FIOS is requred to eventually serve every home like cable is.

According to my town administrator's office, they're not.

I've heard rumors that in some cases you can pay them (like a couple of thousand dollars) to hook you up, if they have decided not to offer you service.

Quote:
Originally Posted by DoubleDAZ View Post

I just wish the FCC (i.e., Martin) would admit that what he is doing is blatantly unfair to cable and is forcing cable to compete on a playing field that is not level.

I doubt Martin would ever do anything like that.

Quote:
Originally Posted by DoubleDAZ View Post

I also think cable expected DirecTV to have more capacity, but I think they missed the boat on how quickly cablenets would convert to HD broadcasts.

I think that no one expected DirecTV's advertising campaign to be as successful as it was.
post #679 of 2079
4/2/08 at 3:31pm
Quote:
Originally Posted by lobosrul View Post

Wow I didn't realize FIOS was putting out 3800Mbps streams (thats roughly what uncompressed 1080p60 is).

Nothing FiOS provides broadcasts at 1080p60.
post #680 of 2079
4/2/08 at 4:11pm
Quote:
Originally Posted by mrvideo View Post

I've never seen color bars during ABC network primetime. All local breaks either had ABC network promos or PSAs (some network promos are allowed to be replaced by local material). Nor have I seen blacks that last longer than a few seconds. Never seen promo freezes either.

Our local affiliate dumps the promos after the end of the last program of the night. Since that little bit of black is so short, it can look awful when they dump net and go to news.

They must have changed things at some point.

It used to be 10 seconds of freeze on the last promo before local avail with the promo music running ender it. Then you had about 10 seconds of black before their weird looking ABC New York color bars and tone popped up. If an operator fell asleep at the wheel, they sure woke up quick when that happened.
post #681 of 2079
4/2/08 at 4:11pm
Quote:
Originally Posted by PaulGo View Post

From the Consumerist, maybe it should be filed under "Believe it or Not"


Comcast Spews BS When You Complain About HD Degradation

David wanted a straight answer from Comcast as to whether they were degrading his HD signal, but instead was fed a colossal trough of baloney. The executive customer service rep who replied to David's email said Comcast is using a "new system" for HD and while it "works well with clean 1080i signals, we're making some adjustments to improve how it handles other types of HD signals so we can bring you the best HD picture. We apologize this has not created the HD experience that we intended, but we will work towards getting it right. "Sure... check out this previous post, Comcast Degrades HD Quality To Make Room For More Channels, for the science and proof of how Comcast (and other cable operators) are degrading HD feeds to make more money.

Balance of article at:
http://consumerist.com/375341/comcas...hd-degradation

http://www.dslreports.com/shownews/C...D-Signal-93233

Here is a Broadband Reports link that discusses the article.
Appears the secret is starting to get out.

Time to call Comcast and ask how and why they compress their HD
Let them know many channels are not as good as they were when you first got them.

Time to ask for a refund.
post #682 of 2079
4/2/08 at 4:14pm
Quote:
Originally Posted by bicker1 View Post

According to my town administrator's office, they're not.

I've heard rumors that in some cases you can pay them (like a couple of thousand dollars) to hook you up, if they have decided not to offer you service.

I doubt Martin would ever do anything like that.

I think that no one expected DirecTV's advertising campaign to be as successful as it was.

It's not their advertising campaign as much as their service. They were the anchor for a lot of the networks going to HD, and they were willing to pay the networks more for HD content, which cable has been reticent to do. Of course, by being the anchor, they got some nice pricing that I don't think cable can get, so not only do they get to launch the new HD nets, but they make it more expensive for cable to catch up.

This my friends is called initiative, and they bet the farm on being able to beat cable by delivering more HD and higher quality HD for less money than cable charges. For some reason that no one in the cable industry seems to be able to figure out, people seemed to respond well to this and are moving to DirecTV in droves. Funny how fickle people are.
post #683 of 2079
4/2/08 at 4:20pm
Cable actually tried to negotiate Sat channels to "delay" the move to HD.

DirecTV has it's customers in mind, promoted HD channel development, made plans for system expansion and have been very successful.

Cable decided to ignore the problem, then try to pay off the sat channels to NOT go HD and now has issues that they could've taken care of years ago. Both bandwidth AND HD channel wise.

If Verizon can run new fiber-lines from scratch cable could've done it as well. Cheaper, faster and with customers built-in. They dug the hole for themselves.
post #684 of 2079
4/2/08 at 4:35pm
Quote:
Originally Posted by dean-l View Post

Cable actually tried to negotiate Sat channels to "delay" the move to HD.

DirecTV has it's customers in mind, promoted HD channel development, made plans for system expansion and have been very successful.

Cable decided to ignore the problem, then try to pay off the sat channels to NOT go HD and now has issues that they could've taken care of years ago. Both bandwidth AND HD channel wise.

If Verizon can run new fiber-lines from scratch cable could've done it as well. Cheaper, faster and with customers built-in. They dug the hole for themselves.

Cable doesn't need to run fiber to solve this problem. Even if Cable did pull fiber to the home, it wouldn't help them one bit. In fact, VZ is using a very similar architecture to cable for video delivery. What VZ didn't do is burn a crapload of spectrum on carrying a lot of analog channels.

Comcast and others can easily solve this problem by moving 10-20 analog channels to digital, and giving boxes to everyone who complains. but they don't want to do that, because it might cause consumers to think about making a jump to DBS (if you are going to get boxes, then why not look at other options).

The approach they are taking now is yielding a steady bleed of subs to FIOS and DBS. If they moved the channels in one fell swoop, they'd lose a bunch of subs in one big chunk, but would likely halt the defections in the medium term with what they could do with the digital bandwidth. But that would hurt more on wall street, so it's not something they really want to do.
post #685 of 2079
4/2/08 at 4:57pm
Quote:
Originally Posted by MikeSM View Post

It's not their advertising campaign as much as their service.

We'll just have to agree to disagree about that. DirecTV's advertising campaign was one of the most effective I've seen in years. It totally changed the focus of attention of vast portions of the customer-base. Utterly remarkable.
post #686 of 2079
4/2/08 at 4:59pm
Quote:
Originally Posted by MikeSM View Post

but they don't want to do that, because it might cause consumers to think about making a jump to DBS

That, and the fact that, word is, right now there aren't digital boxes to be had, in many areas.
post #687 of 2079
4/2/08 at 5:16pm
Quote:
Originally Posted by bicker1 View Post

That, and the fact that, word is, right now there aren't digital boxes to be had, in many areas.

That I don't buy. It all depends on the price being paid.
post #688 of 2079
4/2/08 at 5:20pm
FYI the information in this thread is slowly starting to proliferate to the common person. A friend sent me the below link yesterday:

http://gizmodo.com/374193/comcast-co...hows-bandwidth

We need to keep spreading the word so they can fix this problem. I know they have the money to clean up this mess quickly if they REALLY need to.
post #689 of 2079
4/2/08 at 5:26pm
Quote:
Originally Posted by MikeSM View Post

That I don't buy. It all depends on the price being paid.

No way to know for sure unless Motorola is willing to say one way or another. If Motorola doesn't have any to sell, the price being paid won't matter a bit.
post #690 of 2079
4/2/08 at 5:59pm
More information about HGTV HD:

Well, I owe Comcast an apology -- the dreadful HGTV HD "no HD" is all HGTV's fault -- or, rather, that of its parent company, Scripps. Food Network HD is in the same boat. Check this out:

http://www.tvpredictions.com/2008/04...-patience.html

There's interesting information in the follow-up comments, so dig through those if you want to learn more.

Bottom line, Scripps synched up the HD channel schedules to the SD channel schedules, essentially doing away with the HD version of the channels. What utter absurdity!!

Good Lord, are ALL the people who have anything to do with putting television on the air absolute, complete, total MORONS?!?!??? I would say "a monkey could do the job better than these idiots," but that would be insulting to all of the monkeys on the planet. Sheesh!!

Ranting over, one thing I need to report is that I have NOT seen any "stretch-o-vision" with the HGTV HD shows, and I haven't noticed a change in the times -- it's more like Comcast is still showing the HD versions -- but at SD quality. I just don't even know what to say anymore.

Oh, wait, I think I did say it before -- heck, we might as well toss our fancy HDTV's out the window, and just watch YouTube. Sheesh, again.
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