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post #1471 of 1497 Old 09-21-2016, 10:29 AM
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Originally Posted by Skytrooper View Post
Not long ago Comcast was slowing the Netflix speed til a agreement was reached. Now they are going to integrate.
Unless Comcast could explain to me how adding more "content" to what is already available isn't going to restrict the bandwidth that is currently allocated to their individual services, I think this might be a bad idea.

Enough is enough. Now if they were to do away with the "must carry" rule for Cable TV channels , I probably wouldn't mind them adding Netflix(which I have through my Tivo (along with Hulu,Amazon Video,Vudu & some others; I've been able to download some 1080p Movies from Amazon that were pretty nice. In the long run I'd just as soon get the Blu Ray of the movie as I prefer to view movies that I know will absolutely be 1080P without the probabilty of "proccessing artifacts")

I'm not sure how I feel about "Streaming". I know for certain I would not subject the music I listen to this ! (That why I use a Digital File Player, the content I play is already "In House";Well actually permanently on a drive unless I delete it)
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post #1472 of 1497 Old 09-21-2016, 06:01 PM - Thread Starter
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Adding Netflix internet content does not use any more bandwidth. It is the same as getting Netflix from a smart TV or any other internet device such as a Blu-ray player.
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post #1473 of 1497 Old 09-21-2016, 07:52 PM
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Originally Posted by jimv1983 View Post
I'm not sure what "stat mulitplex" means but I don't see how the problem could be resolved while I'm not home but always be an issue when I am home.
Go back and read the thread. Statistical multiplexing means that the bitrate is changing second to second, and the other channels that a given channel are being stat multiplex'ed against will thus affect the quality.

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I wonder if a device like this would make a difference for my issue. Apparently the DVDO EDGE is discontinued. Are there any similar units I could try?
You can probably find one somewhere. They clean up Comcast's mess a little bit, and certain types of content looks stunning.

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He,he.he, If you're talking about the Edge's "temperament" at times recognizing new inputs, that's exactly what happened yesterday when I was putting my Tivo back inline with the other two active inputs, (X1 & Oppo 95BDP), I'm running through it.
It occasionally will just go to sleep, or do really strange things that require a sleep/wake and HDMI re-lock cycle. It's usually pretty good though.
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post #1474 of 1497 Old 09-22-2016, 01:50 AM
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Originally Posted by jimv1983 View Post
I'm not sure what "stat mulitplex" means but I don't see how the problem could be resolved while I'm not home but always be an issue when I am home.
Think I mentioned statistical multiplexing earlier on.

Stat muxing is a system that improves picture quality in some situations when you have a finite bandwith.

If you had 16Mbs of bandwith and 2 channels to compress, you could encode them all using CBR (Constant Bitrate) at 8Mbs. Nice and simple. However at any given moment, one channel may be showing content that is really simple to compress and could deliver high quality results at 4Mbs, whilst another could be showing really demanding content that may be compromised by 8Mbs compression and be better encoded at a higher bitrate, such as 12Mbs. It would obviously be better to drop one channel to 4Mbs and increase the other to 12Mbs - but together they still only take 16Mbs. This happens on the fly, with both channels encoded VBR (Variable Bit Rate), with both channels' content analysed and a bitrate for each encoder decided dynamically on the fly.

If both channels are showing easy stuff - then they easily have great picture quality. If both channels have demanding stuff, then you hit a brick wall and quality suffers. Statmuxing two channels together is a very basic example, it is much more common to statmux 3+ channels, and in some cases you can also weight the bandwith each channel has as an average (so premium channels may be weighted to win more bitrate than less premium stuff in demanding situations where competition between channels in the mux for bitrate is high)

So one channel's content can impact another's if they are in the same stat mux. Similarly, if some channels are off-air for certain parts of the day, or show content which is trivial to compress (talking heads, relatively static graphics etc.) for some parts of the day but not others, then other channels may show a quality difference as a result. Chosing which channels to statmux together is a non-trivial exercise...
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post #1475 of 1497 Old 09-22-2016, 01:56 AM
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Originally Posted by newStevea View Post
I'm not sure how I feel about "Streaming". I know for certain I would not subject the music I listen to this ! (That why I use a Digital File Player, the content I play is already "In House";Well actually permanently on a drive unless I delete it)
Netflix streaming is pretty decent, certainly compared to the quality of some US cable and OTA I've seen. Sure you can see compression artefacts, but the non-real time encoding that Netflix use for their content is pretty optimised for the sources they use, and at the higher bitrates looks pretty good. It's not Blu-ray - but it's a lot better than some conventional TV I've seen in the US. (I saw a lot of heavily compressed, probably MPEG2, when I was there a few years ago.)

As for audio - Spotify Extreme streaming and download bitrate is around 320k, using Ogg Vorbis compression. This should deliver audio at a higher quality than an iTunes 256k AAC download, though if you rip from CDs and use lossless compression (Apple Lossless, FLAC, WAV etc.) then your local content will be at a higher quality. That said 320k Ogg is, for many, difficult to differentiate from a lossless source.
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post #1476 of 1497 Old 09-22-2016, 08:19 AM
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Originally Posted by BiggAW View Post
Go back and read the thread. Statistical multiplexing means that the bitrate is changing second to second, and the other channels that a given channel are being stat multiplex'ed against will thus affect the quality.



You can probably find one somewhere. They clean up Comcast's mess a little bit, and certain types of content looks stunning.





It occasionally will just go to sleep, or do really strange things that require a sleep/wake and HDMI re-lock cycle. It's usually pretty good though.
I'm not sure but I think the trick might be make sure the Edge is switched to another active & on input when you're adding a new input. It normally responds well to rebooting it , if it doesn't see things the first time around.





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Netflix streaming is pretty decent, certainly compared to the quality of some US cable and OTA I've seen. Sure you can see compression artefacts, but the non-real time encoding that Netflix use for their content is pretty optimised for the sources they use, and at the higher bitrates looks pretty good. It's not Blu-ray - but it's a lot better than some conventional TV I've seen in the US. (I saw a lot of heavily compressed, probably MPEG2, when I was there a few years ago.)

As for audio - Spotify Extreme streaming and download bitrate is around 320k, using Ogg Vorbis compression. This should deliver audio at a higher quality than an iTunes 256k AAC download, though if you rip from CDs and use lossless compression (Apple Lossless, FLAC, WAV etc.) then your local content will be at a higher quality. That said 320k Ogg is, for many, difficult to differentiate from a lossless source.
I wasn't being totally honest when I made my comment about how I feel about streaming . I think even at their best situation scenarios
what is possible using it is a bit mediocre compared to using other means of transmitting media.

For myself it's been awhile since I've really had any "conventional TV" viewing issues, I don't spend any time watching SD programming & I'm not experiencing many of the issues that many people seem to be having with whoever & however their Broadcasting content is being provided to them.

As for my first love ~Music~ I have a Music Library (That I've been accumulating over 30yrs or so) that has no shortage of high quality content. Most of this Library has been ripped (always to uncompressed WAV) to portable external hard drives. I mulled over trying "Tidal" , but my Auraliti PK100 Digital File Player lacks the capability to work as an Internet Music Server. I would only use a Computer to play music if I were to take the steps to convert it into a Dedicated Music PC. Without taking these steps a Computer is only Mediocre at playing back the marvelous music files it's able to process. An old saying comes to mind here "You can't make a silk purse out of a Sow's ear" .

The music that I play certainly benefits quite a bit more "attention to detail" than affording it a mediocre means of playback can provide. (I'm just glad none of my 2TB library drives were close enough to hear the words "320kbps" & "256k aac" etc.; Oh the Horror)
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post #1477 of 1497 Old 09-22-2016, 11:02 AM
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Originally Posted by BiggAW View Post
Go back and read the thread. Statistical multiplexing means that the bitrate is changing second to second, and the other channels that a given channel are being stat multiplex'ed against will thus affect the quality.



You can probably find one somewhere. They clean up Comcast's mess a little bit, and certain types of content looks stunning.



It occasionally will just go to sleep, or do really strange things that require a sleep/wake and HDMI re-lock cycle. It's usually pretty good though.
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Originally Posted by sneals2000 View Post
Think I mentioned statistical multiplexing earlier on.

Stat muxing is a system that improves picture quality in some situations when you have a finite bandwith.

If you had 16Mbs of bandwith and 2 channels to compress, you could encode them all using CBR (Constant Bitrate) at 8Mbs. Nice and simple. However at any given moment, one channel may be showing content that is really simple to compress and could deliver high quality results at 4Mbs, whilst another could be showing really demanding content that may be compromised by 8Mbs compression and be better encoded at a higher bitrate, such as 12Mbs. It would obviously be better to drop one channel to 4Mbs and increase the other to 12Mbs - but together they still only take 16Mbs. This happens on the fly, with both channels encoded VBR (Variable Bit Rate), with both channels' content analysed and a bitrate for each encoder decided dynamically on the fly.

If both channels are showing easy stuff - then they easily have great picture quality. If both channels have demanding stuff, then you hit a brick wall and quality suffers. Statmuxing two channels together is a very basic example, it is much more common to statmux 3+ channels, and in some cases you can also weight the bandwith each channel has as an average (so premium channels may be weighted to win more bitrate than less premium stuff in demanding situations where competition between channels in the mux for bitrate is high)

So one channel's content can impact another's if they are in the same stat mux. Similarly, if some channels are off-air for certain parts of the day, or show content which is trivial to compress (talking heads, relatively static graphics etc.) for some parts of the day but not others, then other channels may show a quality difference as a result. Chosing which channels to statmux together is a non-trivial exercise...
Ok. That explanation makes sense but it seems pretty clear that that isn't my issue. My picture is consistently bad. It seems unlikely that the "stat muxing" process would result in a good signal when I'm gone not watching TV(or when the DVR is recording) but good other times. Especially with the same show on the same channel viewed only minutes apart. I watch a show at home at it looks awful possibly because of low bandwidth. 5 minutes later the bandwidth for that same show on the same channel is higher. Then 5 minutes after leaving the pizza place the bandwidth for that same channel broadcasting the same show is now lowered again and then stays low anytime I'm watching or recording. I guess it's possible but I'd guess it's astronomically unlikely.
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post #1478 of 1497 Old 09-22-2016, 02:31 PM
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Originally Posted by sneals2000 View Post
Think I mentioned statistical multiplexing earlier on.

Stat muxing is a system that improves picture quality in some situations when you have a finite bandwith.

If you had 16Mbs of bandwith and 2 channels to compress, you could encode them all using CBR (Constant Bitrate) at 8Mbs. Nice and simple. However at any given moment, one channel may be showing content that is really simple to compress and could deliver high quality results at 4Mbs, whilst another could be showing really demanding content that may be compromised by 8Mbs compression and be better encoded at a higher bitrate, such as 12Mbs. It would obviously be better to drop one channel to 4Mbs and increase the other to 12Mbs - but together they still only take 16Mbs. This happens on the fly, with both channels encoded VBR (Variable Bit Rate), with both channels' content analysed and a bitrate for each encoder decided dynamically on the fly.

If both channels are showing easy stuff - then they easily have great picture quality. If both channels have demanding stuff, then you hit a brick wall and quality suffers. Statmuxing two channels together is a very basic example, it is much more common to statmux 3+ channels, and in some cases you can also weight the bandwith each channel has as an average (so premium channels may be weighted to win more bitrate than less premium stuff in demanding situations where competition between channels in the mux for bitrate is high)

So one channel's content can impact another's if they are in the same stat mux. Similarly, if some channels are off-air for certain parts of the day, or show content which is trivial to compress (talking heads, relatively static graphics etc.) for some parts of the day but not others, then other channels may show a quality difference as a result. Chosing which channels to statmux together is a non-trivial exercise...
Yup. That's a good explanation. I was way too tired to explain it again last night. In actual terms for MPEG-4 HD, U-Verse/Vantage compresses each channel on it's own (not sure if it's CBR or a VBR average target), and they need about 6mbps minimum for a mediocre quality picture. Comcast is stat multiplexing 8-10 channels per 38mbps QAM in MPEG-4, and getting similar results. Stat multiplexing really started to get big with MPEG-2 HD 3 per QAM, then we went to 4, now with MPEG-4, it's 8-10. DirecTV's TPs are also 38mbps, and they are running 6-7 MPEG-4 HDs per QAM, for about the same average bitrate as U-Verse/Vantage, and because of the advantage of stat multiplexing, their picture quality is excellent. I believe FiOS does 5 MPEG-4 HDs per QAM, but it's kind of irrelevant, as their MPEG-4 channels are channels almost no one actually watches, and they do some 3 per QAM stat multiplexes for MPEG-2.

For this discussion, what is being stat multiplexed at that point in time is very important. If xyz channel is being stat multiplexed against a news channel and a comedy channel, let's say, the quality of xyz channel is going to be a LOT better if the news channel has talking heads on, and the comedy channel has a stand-up comedian with a fixed camera angle than if the news channel has live video of violent protests and the comedy channel has some 1980's movies with a bunch of comedic action, as the latter scenarios are going to take a lot more bandwidth out of the mux than the former. It starts to get weird when MSNBC shows Olympics, for example, as MSNBC is otherwise presumed to have talking heads. It was a mess when they showed sailing, and who knows what it did to the other channels on the mux, as water is the hardest thing to compress, and Al Sharpton yelling at the camera with most of the screen covered in graphics is about the easiest.

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I'm not sure but I think the trick might be make sure the Edge is switched to another active & on input when you're adding a new input. It normally responds well to rebooting it , if it doesn't see things the first time around.
Yeah, I try to return it to my TiVo, which is always outputting a signal, and it seems to behave OK.

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I wasn't being totally honest when I made my comment about how I feel about streaming . I think even at their best situation scenarios
what is possible using it is a bit mediocre compared to using other means of transmitting media.
With offline encoding and buffering, Netflix is able to run at below cable bitrates with far higher quality. Vudu has some movies that are indiscernible from Blu-Ray, while others aren't encoded very well, at least that was my experience. Inconsistency. I'm picky about quality, but I find Netflix streaming and Spotify's 320kbps mode to both be excellent quality.

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Originally Posted by jimv1983 View Post
Ok. That explanation makes sense but it seems pretty clear that that isn't my issue. My picture is consistently bad. It seems unlikely that the "stat muxing" process would result in a good signal when I'm gone not watching TV(or when the DVR is recording) but good other times. Especially with the same show on the same channel viewed only minutes apart. I watch a show at home at it looks awful possibly because of low bandwidth. 5 minutes later the bandwidth for that same show on the same channel is higher. Then 5 minutes after leaving the pizza place the bandwidth for that same channel broadcasting the same show is now lowered again and then stays low anytime I'm watching or recording. I guess it's possible but I'd guess it's astronomically unlikely.
Not if it happens over and over again at different times of the day. If it was one time, it could be a stat multiplexing issue.
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post #1479 of 1497 Old 09-22-2016, 04:48 PM
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Not if it happens over and over again at different times of the day. If it was one time, it could be a stat multiplexing issue.
So you are saying that the stat multiplexing just happened make the picture quality better at exactly the time I was viewing from another TV and then went back to the usual in the 5 minutes I was driving?

I really wish I could capture exactly what I'm seeing but the camera on my phone just doesn't seem to pick it up very well.

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post #1480 of 1497 Old 09-22-2016, 06:48 PM - Thread Starter
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So you are saying that the stat multiplexing just happened make the picture quality better at exactly the time I was viewing from another TV and then went back to the usual in the 5 minutes I was driving?

I really wish I could capture exactly what I'm seeing but the camera on my phone just doesn't seem to pick it up very well.
I really doubt if you watched the same channels that you should notice any difference in picture quality. The multiplexing the Comcast uses has been refined and works quite well (a very high percentage of the time). I have not noticed any picture problems on my TVs including any degraded picture quality (I have eight TVs four are hooked up to X1 boxes and four are connected to HD DTAs). Does your area have cloud TV enabled? If so how does the picture look on your computer and better yet how does it look if you hooked your TV up to your computer? I know the picture comes from different sources (IP vs QAM) but if you get a clear picture from your computer on your TV you can show that to a Comcast Tech and let them figure it out. If they can't you can file a complaint with your local cable commission since Comcast is not provide they quality signal you are paying for.
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post #1481 of 1497 Old 09-23-2016, 01:44 AM
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Originally Posted by jimv1983 View Post
Ok. That explanation makes sense but it seems pretty clear that that isn't my issue. My picture is consistently bad. It seems unlikely that the "stat muxing" process would result in a good signal when I'm gone not watching TV(or when the DVR is recording) but good other times. Especially with the same show on the same channel viewed only minutes apart. I watch a show at home at it looks awful possibly because of low bandwidth.
If you are watching exactly the same feed in two different locations - then both channels will be identical in quality as they are encoded once by the same encoder and modulated once by the same modulator. If you are receiving the same feed as the other viewing location, you are getting exactly the same data. There won't be a bandwith issue because QAM cable doesn't work like that - you don't get lower quality in one area than another when receiving the same content encoded by the same encoder. (It's not like IP streaming where you can switch between various quality streams based on available bitrate/bandwith)

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5 minutes later the bandwidth for that same show on the same channel is higher. Then 5 minutes after leaving the pizza place the bandwidth for that same channel broadcasting the same show is now lowered again and then stays low anytime I'm watching or recording. I guess it's possible but I'd guess it's astronomically unlikely.
If consistently the picture quality is worse when viewing in your home location and your pizza place, and you are sure they are watching an identical feed, then you need to look at your display.

Have you disabled every single bit of digital processing (noise reduction, image enhancement, sharpness down to minimum, MotionFlow/Natural Motion switched off, contrast enhancement, black level enhancement etc. all inhibited). Whenever I buy a new display I spend 10s of minutes disabling all the digital processing that just makes pictures look like junk. Slowly I re-enable some features to see their effects - but if I'm honest, I usually keep all of them disabled on most displays.

The difference this can make to picture quality cannot be understated.
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post #1482 of 1497 Old 09-23-2016, 07:21 AM
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I'm a bit curious as to what the X1 is using to record with. For some reason it doesn't remind me of any drive I can recall in any DVR that I've ever used ?

I want to say that it doesn't appear to operate like it's using a "mechanical" drive. Is it using a SSD ?

Another thing I've noticed is that on previous Comcast set top boxes I've had I thought that watching an "On Demand" HD program was a step back from watching the same program if I'd recorded it with my Tivo. There was always some slight "mosquito noise"(& I do mean slight) in the "On Demand" viewing that reminded you that you weren't viewing the Broadcast regardless of how "close" it was to that ! I honestly wouldn't record as much as I did if "On Demand" was comparative in PQ !

Unless I happen to have a non standard X1 box , the X1 is leaps & bounds more technically capable than anything that I've used from Comcast before this ! If for some reason I forget to set a recording (& I can't believe I'm saying this), I'll watch it "On Demand" (without regretting the fact I'm watching "On Demand)!

I don't know,but I think that the Cisco tech that they're currently using has definitely "raised the bar" in what they're able to provide.

(& this is from someone that I'm "renting" the equipment I'm using from ???? ; Now if they could just reduce a bit of all the Consumer, or as I like to call them "Technophobes", friendly features they add to things I'd be happy,...shocked,but happy)
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post #1483 of 1497 Old 09-23-2016, 11:29 AM
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Originally Posted by PaulGo View Post
I really doubt if you watched the same channels that you should notice any difference in picture quality. The multiplexing the Comcast uses has been refined and works quite well (a very high percentage of the time). I have not noticed any picture problems on my TVs including any degraded picture quality (I have eight TVs four are hooked up to X1 boxes and four are connected to HD DTAs). Does your area have cloud TV enabled? If so how does the picture look on your computer and better yet how does it look if you hooked your TV up to your computer? I know the picture comes from different sources (IP vs QAM) but if you get a clear picture from your computer on your TV you can show that to a Comcast Tech and let them figure it out. If they can't you can file a complaint with your local cable commission since Comcast is not provide they quality signal you are paying for.
I assure you there is a difference. Yes, cloud TV is enabled in my area. The picture streaming to my computer is pretty good. Much better than what I'm getting from the box. The same is true when connecting my laptop to the TV. The streaming from the laptop to my TV is a little pixelated but pretty good overall. I have showed them and they still don't know what is going on. I've had 3 techs that have looked at it and agreed that they see the issue I'm am talking about.

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If you are watching exactly the same feed in two different locations - then both channels will be identical in quality as they are encoded once by the same encoder and modulated once by the same modulator. If you are receiving the same feed as the other viewing location, you are getting exactly the same data. There won't be a bandwith issue because QAM cable doesn't work like that - you don't get lower quality in one area than another when receiving the same content encoded by the same encoder. (It's not like IP streaming where you can switch between various quality streams based on available bitrate/bandwith)



If consistently the picture quality is worse when viewing in your home location and your pizza place, and you are sure they are watching an identical feed, then you need to look at your display.

Have you disabled every single bit of digital processing (noise reduction, image enhancement, sharpness down to minimum, MotionFlow/Natural Motion switched off, contrast enhancement, black level enhancement etc. all inhibited). Whenever I buy a new display I spend 10s of minutes disabling all the digital processing that just makes pictures look like junk. Slowly I re-enable some features to see their effects - but if I'm honest, I usually keep all of them disabled on most displays.

The difference this can make to picture quality cannot be understated.
Then despite getting the signal from the same head end as the pizza place the signal coming into my home isn't exactly the same as the signal coming into the pizza place. My thought that was there was some line issue either between the head and and the node or between the node and my home that isn't occurring on the lines going to the pizza place.

As I have said it is NOT the TV. Noise reduction and image enhancement features are all off. Sharpness isn't at the minimum but very low (like 10/100). I do have the motion feature on custom with low settings for DeBlur and DeJutter. Also, I have the same TV settings applied to ALL inputs with no issues on any of the other sources. Also, one of the Comcast techs brought a TV with them that they use for testing. I think it was 24" (my TV is 55"). That test TV has the EXACT same issue. The fact that the issue does't appear on other sources on my TV(using the same TV settings) and DOES appear from the X1 box on both my TV and another TV tells me that it ISN'T the TV. Also, as I have said in previous comments, the box has been replaced so it isn't that either. The drop to my house has also been replaced.

Different boxes
Different TVs
Different HDMI cables
Drop replaced
I even bypassed my internal home wiring.

Poor quality still exists.

Pizza place 2 miles away looks great.

I'm not a cable network engineer so I don't claim to know how everything works but by process of elimination and common sense it's pretty clear that the issue is up stream from my home. Something is happening between the last common source(I'm assuming that would be the head end about 20 miles from my house) for my home and the pizza place and my home.

My only guess is that something is happening on one of the red lines in my attachment. Some kind of interference, bad hardware, etc. I don't know but like I said by common sense and process of elimination I can't think of any other possibility.
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post #1484 of 1497 Old 09-23-2016, 11:43 AM
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...My only guess is that something is happening on one of the red lines in my attachment. Some kind of interference, bad hardware, etc. I don't know but like I said by common sense and process of elimination I can't think of any other possibility.
Perhaps the Pizza Parlor has the fault. Maybe the lighting, setting(s), TV model, or TV age at the Pizza Parlor is different from yours? Perhaps it looks better because the noise you complain of is masked by reduced sharpness or using an RGB connection instead of HDMI. As a contract CATV Sweep Tech I'd say your belief that you're getting a different signal is extremely unlikely IF all the conditions you present are true.

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post #1485 of 1497 Old 09-23-2016, 12:37 PM
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Have the "basic" questions been asked yet?

The first four items on the list below would be the top of my list of things to check, including hitting the "Info" on the TV remote while the TV is using the cable box as input since that will tell you useful information on what the cable box is sending to the TV. Also, since the cable box may be rescaling what it is receiving, double-checking that one is indeed tuned to a HD channel is important, such as "HD" in the program information for the program on that channel or if you have a printed channel line-up published by Comcast that that channel is listed as a HD channel. (Many HD channels have downscaled SD duplicates.)


These are "basic" questions, but, if overlooked, could explain reduced video quality.
  1. Are you tuning to an HD channel, or the SD downscale of that channel? (Most HD channels Comcast also sends as SD. For example, Channel 2 is our ABC affiliate, but on the cable box 2 is the SD downscale and 702 is the HD. Same with many cable networks, e.g., TCM here is 501 SD or 784 HD.)
  2. Are you using a HD-capable connection to the TV? (Generally the best is HDMI; sometimes component, with 3 video signals and 2 audio signals, work around a problem. Either composite (one video connection, two audio connection) or "coax" (typically using NTSC channel 3 or 4) will be SD.)
  3. Is the box configured to send a HD signal out through the connection method? Depending on the box and the TV, suggested choices include NATIVE, 1080p, 1080i, 720p. (Right now I have my cable box set to output 1080p.)
  4. Is there anything between the cable box and the TV that would either reduce the quality or interfere with the EDID information? Easiest test is to connect the cable box directly to the TV and then see what the TV reports for the signal it is being fed, typically by hitting the "Info" button on the TV remote.
  5. Is the firmware in the TV current? From time to time a TV manufacturer will update the software in the TV to fix problems, particularly with the HDCP handshake, and sometimes the factory-installed software is out-of-date. (My 50-in TV wanted to update its software the moment I connected it to the Internet.)
  6. Have you turned "overscan" off? Overscan is a slight zoom (2-5%), a vestige from the CRT days, but many TV manufacturers ship their TVs with this option set on. Not only does this lose a bit of the picture around the edges, but it also means no more 1:1 mapping of 1080p, which slightly reduces the sharpness of the picture.
  7. Have you configured the TV to neither "sharpen" nor "soften" the picture? Sometimes different inputs will have their own set of settings for sharpness and other controls, so one may have to do the adjustments with the Input set for the cable box. Sometimes adjusting a few parameters may improve the appearance, but it is best to start out with most, if not all, of the TV enhancements set to the least amount of tinkering as possible to the picture. Depending on the model, 0 does not necessarily mean no changing of the picture. (E.g., on one of my TVs a sharpness setting of 0 means soften the picture, i.e., I lose detail; but the factory reset sets the sharpness too high so people look like they are pasted onto a background.)

My very humble setup:
Spoiler!
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post #1486 of 1497 Old 09-23-2016, 01:19 PM
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Originally Posted by olyteddy View Post
Perhaps the Pizza Parlor has the fault. Maybe the lighting, setting(s), TV model, or TV age at the Pizza Parlor is different from yours? Perhaps it looks better because the noise you complain of is masked by reduced sharpness or using an RGB connection instead of HDMI. As a contract CATV Sweep Tech I'd say your belief that you're getting a different signal is extremely unlikely IF all the conditions you present are true.
Lighting? Really? You think lighting would be creating the issues I'm seeing? And there is no FAULT at the pizza place. The pizza place looks great. It's the picture at my home that looks like crap. Like I said my sharpness setting is very low (10/100) and I am using HDMI. I've mentioned that as well. It is not a BELIEF. It is a fact. Three Comcast techs have agreed with my findings. All three of them saw the same thing. Two different TVs at my home (mine and the TV the Comcast tech brought) both had the same issue so TV settings is not the issue. All three TVs at the pizza place look great.
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post #1487 of 1497 Old 09-23-2016, 02:27 PM
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So you are saying that the stat multiplexing just happened make the picture quality better at exactly the time I was viewing from another TV and then went back to the usual in the 5 minutes I was driving?

I really wish I could capture exactly what I'm seeing but the camera on my phone just doesn't seem to pick it up very well.
It could happen once, or at the same time every day, but not if it repeats at different times of the day.
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post #1488 of 1497 Old 09-23-2016, 04:23 PM
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It could happen once, or at the same time every day, but not if it repeats at different times of the day.
So let's say the picture quality improving was just a one time thing. Doesn't that seem odd to you that it would clear up just as I'm getting to another place to view and then going back to how it was just as I was going home? It seems like an unlikely coincidence to me. And I don't know if I mentioned it but ALL channels looked good at the pizza place while all channels at home look bad. Although, I did spend most of my time on FOX which seem to suffer the worst. Also, I'm very often home at the time of day where it was crystal clear at the pizza place so I don't think the time of day is the issue.
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post #1489 of 1497 Old 09-23-2016, 05:45 PM
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I'm saying the TVs at the Pizza Joint could be set up different than yours or they may be using component (analog) connection or a signal processing distribution system or they might just have better TVs than you do. That the 'problem' appears on your set and the CableCo's doesn't surprise me. The Cable Company probably uses Hi-Sense or Insignia or other bargain TVs. They buy lots of them and I have no doubt they also break a bunch of them, hence cheap to replace.

Unless you're wrong about the topology of your local Cable system there really is no way I can believe that you and the Pizza Place are getting different encodings of the same program. Different signal strengths and noise levels yes. But neither signal level nor noise level can affect a digital cable signal. Anyway go on believing they are cheating you of PQ. I'm out of this discussion.
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post #1490 of 1497 Old 09-23-2016, 10:14 PM
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Originally Posted by olyteddy View Post
I'm saying the TVs at the Pizza Joint could be set up different than yours or they may be using component (analog) connection or a signal processing distribution system or they might just have better TVs than you do. That the 'problem' appears on your set and the CableCo's doesn't surprise me. The Cable Company probably uses Hi-Sense or Insignia or other bargain TVs. They buy lots of them and I have no doubt they also break a bunch of them, hence cheap to replace.

Unless you're wrong about the topology of your local Cable system there really is no way I can believe that you and the Pizza Place are getting different encodings of the same program. Different signal strengths and noise levels yes. But neither signal level nor noise level can affect a digital cable signal. Anyway go on believing they are cheating you of PQ. I'm out of this discussion.
As I mentioned in a previous reply it is a pizza place that I worked at 5-6 years ago. I personally know the owner. He is pretty cheap. There is no way he would spend money on high end TVs. They are fairly cheap Samsung LCDs. Certainly not the $2,300 I spent on my LG OLED. And he sure as hell wouldn't spend money on a " or a "signal processing distribution system". Also, they are hooked up with HDMI. Yes, Comcast's test TV was some cheap brand but mine is not. The issue is the same on both TVs. Plus, any issue with the TV would show up on other sources. It's just the cable from the X1 box.

I never said Comcast is trying to cheat me out of good picture quality but there IS a problem.

I'm here because I'm looking for real possible answers to why my picture quality is so awful while other places in town look great. I wouldn't be here just wasting my time if it wasn't a real issue.

If all you're going to do is come up with stuff like "it's the lighting" then I don't want you as part of the discussion anyways.
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post #1491 of 1497 Old Yesterday, 03:58 AM
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As I mentioned in a previous reply it is a pizza place that I worked at 5-6 years ago. I personally know the owner. He is pretty cheap. There is no way he would spend money on high end TVs. They are fairly cheap Samsung LCDs. Certainly not the $2,300 I spent on my LG OLED. And he sure as hell wouldn't spend money on a " or a "signal processing distribution system"
Ah - I hadn't spotted you had an OLED.

Chances are you are just seeing how poor your cable feed is, and clearly seeing artefacts that a laggier, lower quality CCFL or LED backlit LCD will mask.

The downside of excellent quality OLED panels is you see just how bad some sources are...

I work in the broadcast production sphere. OLEDs are what we replaced CRT Grade 1 monitors with (for high end picture quality evaluation). There were very few LCDs that came close to Grade 1 quality for critical lighting, colour balance and grading work. Studio cameras have all switched from CRT B&W viewfinders (even for HD) to OLED 7" (and in some critical cases 11") viewfinders - LCD vfs were basically junk for decent studio and OB working.
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post #1492 of 1497 Old Today, 05:59 AM
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Originally Posted by jimv1983 View Post
So let's say the picture quality improving was just a one time thing. Doesn't that seem odd to you that it would clear up just as I'm getting to another place to view and then going back to how it was just as I was going home? It seems like an unlikely coincidence to me. And I don't know if I mentioned it but ALL channels looked good at the pizza place while all channels at home look bad. Although, I did spend most of my time on FOX which seem to suffer the worst. Also, I'm very often home at the time of day where it was crystal clear at the pizza place so I don't think the time of day is the issue.
So then stat multiplexing is probably not the issue. It has to be a box or TV issue then, since the MPEG-2 or MPEG-4 stream going into the two boxes is exactly the same.

Quote:
Originally Posted by jimv1983 View Post
As I mentioned in a previous reply it is a pizza place that I worked at 5-6 years ago. I personally know the owner. He is pretty cheap. There is no way he would spend money on high end TVs. They are fairly cheap Samsung LCDs. Certainly not the $2,300 I spent on my LG OLED. And he sure as hell wouldn't spend money on a " or a "signal processing distribution system". Also, they are hooked up with HDMI. Yes, Comcast's test TV was some cheap brand but mine is not. The issue is the same on both TVs. Plus, any issue with the TV would show up on other sources. It's just the cable from the X1 box.
There's your answer. A cheap TV isn't that good in the first place, so you won't see how crappy Comcast's signal is. Comcast looked bad on my 60" 1080p TV, now it looks horrendous on my 65" 2160p TV.

Quote:
I'm here because I'm looking for real possible answers to why my picture quality is so awful while other places in town look great. I wouldn't be here just wasting my time if it wasn't a real issue.
1. Buy a cheap, poor quality TV from Wal-Mart that won't show you had bad Comcast's feed looks.

2. Get DirecTV for your TV.
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post #1493 of 1497 Old Today, 11:07 AM
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Regarding the Comcast "switchover" on 9/27, what exactly is going to happen? I just received my new set-top box, but I'm not ready to install it because I have a bunch of stuff on my current DVR that I want to dump to VHS to keep it. I won't be able to do that before 9/27. Will I be losing all channels or just HD channels?
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post #1494 of 1497 Old Today, 04:14 PM
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Regarding the Comcast "switchover" on 9/27, what exactly is going to happen? I just received my new set-top box, but I'm not ready to install it because I have a bunch of stuff on my current DVR that I want to dump to VHS to keep it. I won't be able to do that before 9/27. Will I be losing all channels or just HD channels?
Only HD channels. Also, the switchover is done in small steps. Usually a dozen or so channels at a time. On an MPEG-2 only STB, an H.264 channel will still have audio, but a black screen.

Here in the Bay Area, it took Comcast forever to do the switch. I had my replacement STB in the closet for months and just hooked it up last week. You probably have plenty of time to get the content off your DVR.

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post #1495 of 1497 Old Today, 07:03 PM
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Regarding the Comcast "switchover" on 9/27, what exactly is going to happen?
If you are referring to the so-called "HD Enhanced", the cutover of HD channels from MPEG2 to MPEG4, what is likely to happen is that a bunch of HD channels will be cut over to MPEG4, and, if everything is on schedule, additional channels will be cut over in roughly a bunch roughly weekly, probably for a month or two if all goes smoothly.

None of the SD channels are affected; they will stay MPEG2.

None of the local HD broadcast channels are affected (at least that is what I read, and all the over-the-air channels that are available on my local cable are still MPEG2).

But as a channel gets cut over to MPEG4, only MPEG4-capable equipment will be able to display that channel. That means those of us with set top boxes of some kind from Comcast and our package includes non-local HD channels will have to exchange non-compatible boxes for compatible boxes. Those with non-Comcast equipment but using a CableCARD might or might not have to upgrade the equipment the CableCARD is plugged into (e.g., a TV with a CableCARD, or a TiVo).

I haven't noticed any reduction of picture quality for channels that have switched to MPEG4. (I got the HD DVR recent enough that it was MPEG4-capable.) However, I have noticed that recordings from the non-local HD channels take only a third of the disk space per hour than before (which is nice), and also the back-30-second button now more often gets stuck (though rewind seems to still work).

The local HD channels still take as much disk space per hour as they always did, consistent with the claim by Comcast that local HD broadcast channels aren't being changed to MPEG4, but rather left at MPEG2.

My very humble setup:
Spoiler!
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post #1496 of 1497 Old Today, 08:30 PM
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The conversion to H.264 has been pretty leisurely here. 11 channels on 8/4/16 and another 18 on 9/20/16. Still more to go.

Ron

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post #1497 of 1497 Old Today, 11:07 PM
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And even slower just north of where Ron is at. And they've been retaining their native resolution so far, only the early conversions(about a half dozen) were switched to 720 from 1080i.
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