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Old 08-06-2007, 09:59 PM   #61
bkdtv
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Repost...

Do you all see the pixelization when you rewind / instant replay?

As I noted in another post, I see random pixelization on both live and recorded content from Verizon FiOS...but if I rewind / instant replay, I don't see it again. The problem isn't with the recordings since the pixelization never shows up in the same spot twice.

In contrast, for many SA CableCard users, the pixelization issue appears to remains even with instant replay / rewind. So it looks like there are two different issues here -- 1) random pixelization unrelated to source signal, and 2) pixelization related to the signal or decryption of the signal, typically when using Scientific Atlanta CableCards. I bet some users -- especially those with SA CableCards -- are experiencing both issues.

1) Do you use Scientific Atlanta or Motorola CableCards?
2) Do you see the pixelization in the same place when doing instant replay / rewind on live and recorded programming? Always / sometimes?
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Old 08-06-2007, 11:19 PM   #62
TokyoShoe
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Quote:
Originally Posted by bkdtv
Repost...

Do you all see the pixelization when you rewind / instant replay?

As I noted in another post, I see random pixelization on both live and recorded content from Verizon FiOS...but if I rewind / instant replay, I don't see it again. The problem isn't with the recordings since the pixelization never shows up in the same spot twice.

In contrast, for many SA CableCard users, the pixelization issue appears to remains even with instant replay / rewind. So it looks like there are two different issues here -- 1) random pixelization unrelated to source signal, and 2) pixelization related to the signal or decryption of the signal, typically when using Scientific Atlanta CableCards. I bet some users -- especially those with SA CableCards -- are experiencing both issues.

1) Do you use Scientific Atlanta or Motorola CableCards?
2) Do you see the pixelization in the same place when doing instant replay / rewind on live and recorded programming? Always / sometimes?
Well I got struck by it for the first time today. My Tivo recorded "Escape From New York" in HD off some channel in the 400's. Playback results in constant shots of pixelation at a regular interval of every 5 seconds. It also actually disrupts the audio too.

This is the first and so far only recording I've got this on, and it's aweful. Made the recording unwatchable. I do actually see the pixellation during rewind as well.
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Old 08-06-2007, 11:35 PM   #63
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I had my cablecards (scientific atlanta) installed today on my Tivo HD (latest software) and ran some tests tonight.

First, with regards to the cablecard install, things went pretty well. One of the first two cards didn't take, so he popped a third one in and that one worked fine. It didn't take very long to get it all up and running. Unfortunately, there was a lot of pixelation. The signal strength was at 68 or so, with a SNR of 30. He had a truck come out and boost the signal across the street at the box that feeds myself and 7 other houses in the neighborhood, and that boosted the signal strength up to 90, with a SNR of 35. Unfortunately, there's still noticeable pixelation.

So, tonight I decided to test out both OTA HD and Cox Cable HD signals. I put one tuner on Cox 705 (CBS HD), and the other on Antenna Ch 5.1 (OTA CBS HD), and set both to record. There was significant pixelation on both, with a little more on the cable. For OTA, I had varying numbers of pixelation "incidents", typically somewhere between 3 and 7 per minute. This was with a signal strength of between 97 and 100 in the diagnostic screen. On Cable, it was usually more like 6-8 incidents per minute.

I was doing this between 7:30 and 7:45pm. At 7:45pm, I unplugged the Antenna from the Tivo HD and plugged it directly into my TV, being careful not to move the antenna at all in the process. I watched the next 15 minutes of the OTA CBS HD straight off the TV, and didn't see a single issue. Meanwhile, the Cable HD continued to record on the Tivo, and the recording was still filled with pixelation.

I have noticed that I get occasional pixelation during Live TV that isn't there if I go back and re-watch it, but most of the incidents occur both live and in repeat. I also see occasional pixelation in the Tivo menus.

It seems like the OTA pixelation got worse once the cablecards were installed. I've been watching it with just OTA signals for a week and a half now, and would see some pixelation, but not nearly as much as I do now.

Overall, I'm extremely disappointed right now. My wife was fine with DirecTV. We have an old DVR with Tivo on it in the family room. We have an R15 in the bedroom, which she really dislikes compared to the Tivo. I thought this was my opportunity to move up to HD and still keep the Tivo interface that we both love. I was going to get another Tivo HD for our bedroom.

I'm kicking myself a bit now for jumping on this so quickly, as even if I return the Tivo, I'll still be out a bunch of time, and some money to the cable company. I'll contact Tivo tech support, and hang loose for a little while longer (within my 30 day limit), but so far, things aren't looking good.

I'm not trying to dump on the Tivo HD...I want to love it...just sharing my experience so far.

Thanks,
Jeff

Last edited by jhershauer : 08-07-2007 at 01:12 AM.
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Old 08-06-2007, 11:43 PM   #64
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What kind of cablecards are you using? Also is 90 signal strength really the best you can get on any channel? I have a rat's nest of splitters and I'm still getting a minimum of 93 and some channels at 100.
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Old 08-06-2007, 11:52 PM   #65
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Quote:
Originally Posted by jazmaan
What kind of cablecards are you using? Also is 90 signal strength really the best you can get on any channel? I have a rat's nest of splitters and I'm still getting a minimum of 93 and some channels at 100.
I updated my post. They're Scientific Atlanta cards, and yes, 90 is the best I can get...but it's a heck of a lot better than the 68 I was getting before they came out and boosted things outside. I originally stated that it started out at 50, but that was when I had a splitter between my cable modem and the Tivo HD. I moved the modem to another outlet, and that increased the signal to 68...then 90 after they came out.

I might still have some hope that having them come out and boost the signal more would help, but my OTA test kind of put a damper on that.

Thanks,
Jeff
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Old 08-07-2007, 12:51 AM   #66
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I tried recording a few programs tonight, both digital OTA. The first was 'The Singing Bee', which was unwatchable due to constant pixelation issues. Immediately following it (on a different OTA station) I recorded Hell's Kitchen, with almost zero pixelation.

I didn't do a signal strength check as the Tivo was recording at the time, but on previous checks I've usually received signal strength in the 90-100 range for each of these stations. Therefore, I don't know if it was a signal reception issue, broadcast issue, or Tivo issue.

I have no cablecards.

A few times I have noted Tivo menu pixelation incidents. I have 10ft of HDMI cable between Tivo and TV.

I wish recorded programs would log minimum, maximum, and average signal strength -- it would make diagnosis of these problems much easier.
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Old 08-07-2007, 09:03 AM   #67
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Quote:
Originally Posted by jhershauer
He had a truck come out and boost the signal across the street at the box that feeds myself and 7 other houses in the neighborhood, and that boosted the signal strength up to 90, with a SNR of 35. Unfortunately, there's still noticeable pixelation.
Jeff
What's considered good SNR? Average SNR?
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Old 08-07-2007, 09:20 AM   #68
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Further trials;

I tried a Philips Amplifier, which stated it worked for digital cable. No joy, actually made the situation worse. No matter how I had the gain adjusted the signal on my Tivo for a channel that had a signal strength of 88 prior to adding the amplifier, was no higher than 62.

I might give the Motorola Signal Booster, as many people have had good success according to the CirtuiCity site for issues relatedto signal strength.
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Old 08-07-2007, 04:38 PM   #69
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This comment I posted on the other Pixelation Thread

Pixelation has been reported on the TiVo menu system and I did see it once on the TiVo menu system, for such a short time if this thread did not exist i would not have reported it but the TiVo Menu takes the pixelation problem out the tuner system, cable system and CC, the issue must be in the output electronics/control. Does the output setting make any difference as I do not see this pixelation as much as other are and I am using 1080i fixed and HDMI.
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Old 08-07-2007, 05:12 PM   #70
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I have some pixelation with simultaneous audio dropouts on random channels and also the menu. I would tend to assume it's somewhere in the Tivo hardware since it appears on the menu screen and I don't get pixelation with any other hardware (DVD player, game consoles, old Tivo2 plus cable box, etc.)

It's not bad nor is it frequent, but it is there.
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Old 08-07-2007, 05:43 PM   #71
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Quote:
Originally Posted by Chimpware
Just wanted to start a thread with various troubleshooting measures that have been tested;

3. Cooled system down from 48 C to 43 C using external fan - No Difference.
Is 48C considered hot for either the HD or S3?
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Old 08-07-2007, 06:32 PM   #72
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Is 48C considered hot for either the HD or S3?
No, just wanted to see if this was a factor.
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Old 08-08-2007, 12:04 AM   #73
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Is anybody getting this pixelation problem when not using CC ? I have set up two of these 652 TiVos (for friends) and checked the free HD channels and have observed no problems of pixelation or anything else. We are on Comcast Hartford CT.
Yes. I have no cable cards and it's not even connected to cable. I've seen the little glitch on OTA recordings (SD and HD), Tivo Casts, and Unbox videos.

It is not a damaged data stream. MPEG errors are predictable and persist to the next I-frame. The glitch in the Tivo HD occur randomly and last for a few frames -- in my case, 1 or 2 -- and are almost unnoticable. (1/30th of a second isn't much time.)

Is it annoying? Not really. I've seen far worse. Is it a reason to take it back? NO. Tivo, Inc. will eventually figure out what's screwed up and fix it. Even if it's a hardware issue, They. Will. Fix. It.
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Old 08-08-2007, 01:04 PM   #74
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Anyway, in addition to the channel pixellation, I see periodic menu pixelation, which is very new. I'm on component on my TivoHD, and HDMI on my S3. I'll probably switch to HDMI on the TivoHD to see if it makes any difference.
Yep -- I've seen the menu pixelization a bunch of times too. I in-place swapped my Motorola HD DVR for the Tivo HD and it has all the problems. Pixelization on CC channels. Random audio dropouts (which aren't recorded on the drive) and the menu thing also.

The old Motorols HD DVR sucked badly but it never had these problems. I'm using the identical cables even. (1080i component, TOSlink, etc.)

What a pain.
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Old 08-08-2007, 01:09 PM   #75
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Originally Posted by bkdtv
Repost...
Do you all see the pixelization when you rewind / instant replay?
I have seen this problem. Instant replay and it plays fine. I've also seen a few times when the pixelization was recorded -- but my signal strength is only 68. (One feed split four ways.)

I'm using Time Warner with motorola cable cards.

Also, my audio drop outs are never recorded. Sometimes my stereo has a hard time locking onto the signal when it drops and I loose a few seconds of audio. Much more annoying than the pixelization problems.
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Old 08-08-2007, 02:12 PM   #76
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Well just had the Tech at my house for another 2 hours checking the signal to ensure it was not a cable issue. Only potential problem was a spike intermitently in the signal ingress which we could not trace. He changed every connection on the house, and oustide and we even ran a dry line from teh drop at the street into my house to the Tivo and still intermitent pixelation. He is excalating the issue to Cablevision engineering, but I am not hopeful.
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Old 08-08-2007, 02:26 PM   #77
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Originally Posted by cramer
Is it annoying? Not really. I've seen far worse. Is it a reason to take it back? NO. Tivo, Inc. will eventually figure out what's screwed up and fix it. Even if it's a hardware issue, They. Will. Fix. It.
I totally agree with you on this. I have also seen far worse. The interruptions occur too infrequently for it to be a show stopper. It's minorly annoying, but that's as critical as I see it. Not worth returning the box over, and I do have faith that TiVo can come up with a software tweak to remedy the situation. I believe they've worked out most, if not all, similar issues that appeared with the S3 boxes (I have a S3 and it doesn't have the issue). If it's a hardware issue, it can probably be remedied with a software fix. Minor annoyance and I've love an answer, but I won't lose sleep over it.

I think some people may be returning their boxes prematurely, but that's their choice - guess everyone has to make a decision they are comfortable with.
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Old 08-08-2007, 02:34 PM   #78
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Just an update on my performance of this situation:

I am now consistently getting pixelization on anything HD. It's usually just a little shot of it once during the recording.. but I have now had 2 HD movies recorded that were completely unwatchable due to this issue. Never seems to happen in SD recordings.
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Old 08-08-2007, 03:47 PM   #79
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just got cards put in slots 1 & 2. I do see some pixellating when using the 2nd tuner, not just HD channels. It's not consistent, and sometimes a channel does it, then it clears up, then it may show up on another, anywhere in the lineup

FIOS in AA cty MD, Motorola cards, Tivo is using 8.1.7b, all signal strengths 97-100%, SNR 35-39dB. On the pixellating channels, SNR fluctuates ~2dB over a time period of several seconds.

For my case I subjectively put it as no worse than watching OTA on a weaker station when there's a lot of multipath.

Last edited by bhaas : 08-08-2007 at 03:53 PM.
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Old 08-08-2007, 05:33 PM   #80
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Almost definitive proof the pixelation problem lies within my Tivo. I sat down after a half day with the cable tech again to check out what was on Tivo and I saw a program listed in the main guide listing called Try Swivel Search Now, so I decided to check it out. While watching the Go on A TV Treadure Hunt selection I got the exact same pixelation I have been having on broadcast programs and when I rewound, it was repeatable, same pixelation in the same spot. so then I tried the same video on my other Tivo and it pixelated also, but in different spots, so it is not an issue with the source video.

Anyone want to chime in and explain how this could be caused by the cable signal or cable cards? Thought not.

Come on Tivo, its time to clearly admit the issue, not vaguely allude that some people are having a problem, and give us an ETA for the fix!
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Old 08-08-2007, 05:44 PM   #81
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Quote:
Originally Posted by Chimpware
Come on Tivo, its time to clearly admit the issue, not vaguely allude that some people are having a problem,
When have they denied its their issue. I don't think Pony could be any clearer
Quote:
and give us an ETA for the fix!
What sort of world do you live in where you get ETAs for fixes they don't even seem to know the cause of. That really would be something to complain about if they did that.
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Old 08-08-2007, 05:51 PM   #82
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Quote:
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Come on Tivo, its time to clearly admit the issue, not vaguely allude that some people are having a problem, and give us an ETA for the fix!
I thought TiVo Pony already admitted the issue. See the following thread. I didn't read it as vague, just seemed like they need more info.

http://www.tivocommunity.com/tivo-vb...d.php?t=361495
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Old 08-08-2007, 06:47 PM   #83
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I don't post much here. But I figured I would add my experience with this issue as well.

Picked up the TivoHD a couple of days ago. While waiting for the cable company (Insight) to come install my cable cards I had it connected and updated with the latest software. During this time I messed around with it using the lower end analog channels. No problems to speak of during that time.

Today the tech came out and installed two Motorola cableCards. Install went fine and everything seems to be working. That is with the exception of the pixelation problem that appeared within the first 5 minutes. I have tried a few random things mentioned around the forums here, but nothing seems to fix it.

Like everyone else, I love my Tivo but this is to much money to get a worse experience then I got with my box from the cable company. I will hold out for a couple of weeks. But if things are not fixed by then end of my 30 days I will return it and cancel both my Tivos.

Fingers crossed but not all that hopeful. Take care~
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Old 08-09-2007, 01:06 AM   #84
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My report:

TiVO HD
1 Motorola M Card - Comcast Chicago
100 Signal Strength (go me!)
Monster Clean Power Stage 3 power conditioner / backup
Component Video 1080i

Occassional pixalization (~7-10m) issues on all channels and menus, but less then I saw with the Motorola Comcast HD DVR. Minor annoyance, easily outweighed by the bevy of features and functionality that TiVo offers.

My guess is it is a glitch in the video card output processing, and that makes me hopeful for a software patch. I saw a similar issue with my Radeon 9600xt video card on video a while back and it was fixed with a driver update. If it's a hardware issue that gets resolved in a version update that doesn't effect my machine, TiVo will get hell from me, and I *will* get my unit replaced.

Which means dealing with the idiots at Comcast for swaping cable cards, so I'm keeping my fingers crossed that it will be software fixed.
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Old 08-09-2007, 09:04 AM   #85
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Originally Posted by btwyx
When have they denied its their issue. I don't think Pony could be any clearerWhat sort of world do you live in where you get ETAs for fixes they don't even seem to know the cause of. That really would be something to complain about if they did that.
Never said they denied the issue. The problem is that they have never clearly taken ownership of the issue. When I have spoken to Level 2 Tech. at Tivo they still were recommending I get the cable company to check the line, which I did yesterday. They at no time told me to not spend time troublshooting the issue, nor that they have identified the problem. I even responded to Tivo Pony's post asking whether I should put off further troubleshooting efforts on my side or not, to which I got no response.

My concern is exactly what you are pointing out. If they do not know the source of the issue, then it still could be many factors and hopes of a fix are just that. If they have identified the issue, then communicate that and give us hope that it can be remedied. In addition if the source of the issue has been identified then an ETA for the solution is possible.

As part of my current position I have responsibility for global development so issues with product introductions are not foreign to me. I have found the best solution with respect to these issues is to communicate with customers as often as possible with updates on progress toward the solution. So far all we have gotten is vague statements that they are aware of the issue and are working on it. They has been nothing further really.
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Old 08-09-2007, 07:36 PM   #86
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I just got my cable cards installed today, two Motorola Single-Stream cards on Comcast in the Denver suburbs.

My Tivo HD is connected to my Sony SXRD TV over an HDMI link. I have optical audio output from the Tivo to a Denon receiver.

I have noticed some weird macroblocking issues on a few channels, but nothing especially obnoxious (the slow menus and slower channel changes are far more irritating at this point) it ercertainly doesn't seem to happen with any set frequency. I have not had the opportunity to see if anything weird is going on with recorded shows.

I have noticed a weird pixel smearing along the bottom 1/5 of the screen when jumping into the "Now Playing" screen or other menu screens. It looks like some kind of video artifact of the screen changing. Certainly nothing that gets me particularly concerned.

I do hope that they fix the problem in the near future as, who knows, the probs might get worse for me in the next 30 days after my return/cancellation windows expire.

My Comcast tech will be coming back out in a week or two to put an M-card in the system to avoid extra charges for the 2nd cable card. Will be interesting to see if that causes any new problems. Fortunately he has put Cable Cards in lots of Tivos so he pretty much knows what he is doing.
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Old 08-09-2007, 10:16 PM   #87
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Sigh.

Quote:
Originally Posted by jazmaan
What kind of cablecards are you using? Also is 90 signal strength really the best you can get on any channel? I have a rat's nest of splitters and I'm still getting a minimum of 93 and some channels at 100.
Signal strength (also called carrier level) is only one - usually fairly irrelevant - measure of signal quality, and may not strongly affect S/N. A carrier level which is too low for a receiver (i.e. below the receiver's specification for sensitivity) will cause reception quality issues. On an analog TV receiver, this will be perceived primarily as "snow". The lower the carrier level, the snowier the picture. It may also occasionally cause other artifacts not directly related to the signal level to be more noticeable. In a transmission system, to first order the noise level is fixed by the system topology (number of amplifiers in cascade, ambient temperature of the plant, noise figure of the amplifiers, etc.). In addition to the noise produced by the transmission system, every modulated signal source has some non-infinite C/N ratio. The total C/N of the signal itself is equal to the signal level divided by the sum of the transport noise and the source noise. In most cases, however, the source noise is far lower than the transport system noise, so the overall C/N is just the signal level divided by the transport noise level. The third component to S/N is the noise figure of the receiver itself. Indeed, fundamentally it is this value which determines the receiver sensitivity. A low S/N ratio in an analog signal will result in graininess, color artifacts, or "black snow" in the displayed picture if the input signal level to the receiver is well above its maximum sensitivity.

So why not just increase the signal levels? Well, first of all, too high a signal will cause problems with the signal just as signals which are too low. What's more, increasing the signal levels in the plant may not have a very large effect on the S/N, which is the real measure of signal quality. Increasing the gain of an amplifier at the end of the cascade (behind the house) by 8 or 10 dB may not increase the S/N by more than 1 dB, or even less. On the other hand, 2nd order distortion increases by 2dB for every 1dB increase in signal levels, and 3rd order distortion increases by 3dB for every 1dB increase in signal levels. Second and especially 3rd order distortion will really do a number on signal quality. 'And that is for an analog AM signal, where there is a direct relationship between carrier/noise and signal/noise.

OK, that's for analog signals. What about digital signals? Well, there we're really out of the relatively simple S/N world and into the world of distortion and ingress much more than of S/N. A "perfect" analog video signal is anything above 65dB S/N. That is to say, double blind studies have determined that no human subject can tell the difference between a video signal with a 65dB S/N and one with an 80dB S/N. The average consumer cannot tell the difference between a 60dB S/N and a 65dB S/N in pictures displayed side by side. Most consumers can tell a slight difference between a 50dB and 55dB S/N displayed sequentially (not side by side). The analog signal degrades rather gracefully, however, with the picture being poor but still identifiable even with a 15dB S/N. Digital signals do not degrade gracefully. The lowest possible recoverable digital S/N is 6dB, but most systems - especially tuneable broadband systems - require much higher S/N that that to be able to recover a signal. Nonetheless, no matter what the maximum sensitivity, the recovered data will be essentially "perfect" (usually specified as either better than 1 billion or 1 trillion bits per error depending on the system) down to a certain S/N level, at which point decreasing the S/N by even 1dB will produce significant errors. The difference between an essentially perfect data recovery and a complete loss of all data may be as little as 3dB. For signals well in the optimum range of signal levels and S/N, a change of 2 or 3 dB won't make a difference to a digital receiver, but a change of 2 or 3 dB in distortion can make a huge difference.

The bottom line is this: Once a digital signal is "good", increasing the signal level does nothing whatsoever (except allow the system a little headroom to degrade over time without impacting reception). An analog signal which suffers an error only loses the information on the screen for the duration of the error, which may be exceedingly - perhaps imperceptibly - brief. Without forward error correction (which increases bandwidth significantly for the same amount of information transferred), the loss of a single bit, which may be a mere .01 microseconds in extent in a CATV broadcast video stream, will cause an entre packet of information to be lost. Depending on the encoding and whether it is an I-frame or a B-frame, this single lost bit may produce a very noticeable glitch in the picture. Once the signal level is above the maximum receiver sensitivity and the S/N is above the digital recovery threshold, increasing the signal level only increases the likelihood of lost packets due to distortion or common mode rejection issues due to receiver overload.

Last edited by lrhorer : 08-09-2007 at 11:24 PM.
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Old 08-09-2007, 11:16 PM   #88
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Don't muddy the issue

Quote:
Originally Posted by Chimpware
Almost definitive proof the pixelation problem lies within my Tivo. I sat down after a half day with the cable tech again to check out what was on Tivo and I saw a program listed in the main guide listing called Try Swivel Search Now, so I decided to check it out. While watching the Go on A TV Treadure Hunt selection I got the exact same pixelation I have been having on broadcast programs and when I rewound, it was repeatable, same pixelation in the same spot. so then I tried the same video on my other Tivo and it pixelated also, but in different spots, so it is not an issue with the source video.

Anyone want to chime in and explain how this could be caused by the cable signal or cable cards? Thought not.
This is clearly not likely to be an issue with the CATV company or the Cable Cards, but it is also extremely unlikely to be related to the 2nd slot issue, isn't it? What's more, it gives us a better handle on what is happening, or at least one of the things that may be happening. Note the tone of your posts strongly suggest you think there is a single problem. I seriously doubt this to be the case, but one never knows. To wit, the CATV plant / HD receiver / CableCard system is not by any means guaranteed to deliver an informationally identical data stream to the hard drive system as that sent from the CATV headend. The extra TiVo content, however, comes over the internet via TCP, and it DOES guarantee delivery of every packet intact to the I/O subsystem.

On the other hand, if the pixelization is identical in every spot every time you run the video, then either the data somehow got corrupted between the TCP stack and the hard drive write head, or else there is a systemic error in getting the data off the drive and into the video section of the TiVo.

Another poster, however, is saying he is seeing variability in the errors from a single program, meaning in his case the data must be good on the drive and there is some intermittent problem between the hard drive and the video output system.

These three scenarios as related are almost certainly mutually excluded from having a single cause. Now either the reports from the people who are experiencing these problems are inaccurate and misleading, or there are at least three different problems running around here. The reports and quantitative analysis of the actual symptoms need to be firmly resolved and communicated or else no one will very likely be able to fix any of them, regardless of whose equipment is at fault.

This is not aimed at just you. Everyone who is experiencing an issue needs to be far more detailed and exacting in reporting it, or it possibly may never be resolved in a reasonable time. Be explicit, succinct, thorough, and clear. Report the serial number of the box, frequency of the problem's occurrence, duration of the events, and an estimate of how much of the screen area is involved. Is the interval highly regular, somewhat regular, or highly random? Is the audio impacted always, sometimes, or never? Are both analog and digital audio affected? Turn on Closed Captioning. Is it impacted? How? Will rewinding the video and replaying it clear the error? Does rewinding affect the error at all (audio, video, or Closed Captioning)? If you have the ability to try both component and HDMI connections, does it make a difference? Closely examine a single section of video again and again under different conditions to make the determination. Try a downloaded Amazon Unbox video. Does the problem with downloaded video look and feel identical to videos recorded from cable? Does the issue seem to coincide with highly active video (like smoke or swaying fields of grain)? Does the issue happen when specific colors are present (especially large amounts of red)? Is it worse on bright pictures or dark ones? Are pictures either with lots of edges (like a field of flowers or a crowd of people) or with smooth backgrounds (like a tabletop or a blank wall) affected more?

Carefully observing the issue and answering these questions and similar questions could get at the heart of the issues - or at least define them - very quickly, rather than dragging on with vague post after vague post and eratic calls to TiVo support.

(BTW, on my Series III I have never had a single pixelization on downloaded content.)
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Old 08-09-2007, 11:17 PM   #89
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Well, I've been seeing more pixelation tonight on several channels. Interestingly (or not) we watched the first half of a movie on the Tivo HD and finished watching it in another room on the Motorola HD Tuner box (non DVR).

Bottom line is there was no artifacting in this movie on the Motorola box but there was noticeable (distracting) artifacting when watching the movie on the Tivo.

There are a few basic things that any digital tuner should do, producing a picture without noticeable artifacts (macroblocks, etc) is one of them. While I realize that there will be some encoding macroblocking due to the compression that the digital cable system uses, this appears to be something else entirely. Also, as others have noted, it is happening in the Tivo menus.

Hopefully there is a fix for this and a few other things (I had a lockup this evening just browsing channels) very soon as I have 30 days from today to cancel my Tivo subscription.
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Old 08-09-2007, 11:25 PM   #90
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One interesting thing I've noticed about this problem is that it always affects only the lower portion of the screen. I've never seen it happen on the upper portion of the screen.

Definitely seems to be some kind of buffering/video output sort of problem to me. Maybe the drivers for the new video chipset aren't as solid as they ought to be.
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