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D* Verified MPEG4 720p Image Breakup

post #1 of 114
11/28/08 at 2:45am
Thread Starter 
I have been noticing that once every 30 minutes or so you get what looks like a brief (1 frame) glitch in the picture as you see something happening - though not exactly sure what it was.

Over the past several days I began to realize I was only seeing it only on 720p only channels - none of the 1080i channels.

So I began looking at ABC/FOX East/West on different DVRs (HR20-100 and HR20-700), different TVs and different locations to and it clearly is happening on both. When it happened, I stopped the DVR and stepped frame by frame to see exactly what was happening - and it seems the top part of the frame is correct, but the bottom part of the frame shifts slightly.

I have changed the output of the various DVRs to 1080i and 480i/p only as well to see if it is something in the DVRs (Again, different models - different firmware). All output resolutions show the same issue.

I then went to ESPN-HD MPEG4 feed on 206 to see if the same thing happened there, while also monitoring the MPEG2 feed on Channel 72 on a different DVR.

After 50 minutes of monitoring, yes, ESPN-HD MPEG4 /206 did have the shift. The MPEG2 channel DID NOT have the shift, thus it clearly is an issue in D*s MPEG4 encoders - not their receiving equipment at D's uplink site.

I have searched this and the other site - dbstalk.com - for anything relating to 720p and image shift or breakup etc. I find many reports of breakups on ESPN etc, but usually they are dismissed with many saying "no problem here - reboot your receiver" and no one has yet to connect the dots.

Is this covered anywhere that I am not looking?

And has anyone else taken steps to narrow down this issue making D* aware of the issue?

MPEG4 - Channel 206


MPEG2 - Channel 72



Again, let me stress you will NOT see this with the naked eye - only a quick flash in the picture 1 frame out of 60 in a second - almost like what one would see with a power surge or power spike.

Also, the top to bottom percentage is not ALWAYS the same. Usually its closer to 50/50 than what I am showing above.
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post #2 of 114
11/28/08 at 4:28am
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24 Redemption - MPEG4 Channel 398 FoxHD East



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post #3 of 114
11/28/08 at 8:33am
I noticed this last week watching Fox football (720p) via D* on my HR20-700. I was going to post something about it but was unsure how to describe it without visual evidence/screen caps. You've nailed it exactly. Thanks.
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post #4 of 114
11/28/08 at 9:58am
I haven't seen it yet myself and I can usually spot stuff like this on the fly since I pretty much have to in my line of work. I've spotted similar things in game feeds and other broadcast material at work. However, the only 720p stations I watch on D* are my local Fox and ABC. I don't watch ESPN.

I have HR21, which seems to be the biggest difference for me. I wonder if this limited to the HR20 series or if I just need to watch more TV...
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post #5 of 114
11/28/08 at 10:42am
Quote:
Originally Posted by NetworkTV View Post

I have HR21, which seems to be the biggest difference for me. I wonder if this limited to the HR20 series or if I just need to watch more TV...

I've seen it on my HR20, HR21, and H21. It's not the equipment on our end, it's DirecTV. I've never posted about it because it's not really THAT big of a deal to me, but it's definitely there.
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post #6 of 114
11/28/08 at 11:44am
Well, I hope they correct it because that's not right. Good job BeachComber.
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post #7 of 114
11/28/08 at 11:57am
Quote:
Originally Posted by Jeremy W View Post

I've seen it on my HR20, HR21, and H21. It's not the equipment on our end, it's DirecTV. I've never posted about it because it's not really THAT big of a deal to me, but it's definitely there.

Like I said, the only 720p stations I watch are Fox and ABC. Even then, it's only like 2 shows on each network. I'm probably just not watching at the right moments.
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post #8 of 114
11/28/08 at 2:14pm
It looks like the luminance shifts horizontally but the color stays centered. In the top image image the shift was to the left while the one on the bottom was shifted to the right. I tried re-sizing the images to 720p and then shifting the bottom part of the image luminance only. While there is some ghosting remaining due to Y/C crosstalk of the capture process, it gets back much closer to normal:



Both took about 70 pixels of shift. As the images look to be somewhat zoomed from optical capture, I would guess the actual shift is around 64 pixels, or around 4 macroblocks.
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post #9 of 114
11/28/08 at 4:13pm
Looks like you've nailed it. Do you have a DBSTalk account, to post this in the DirecTV Programming forum over there?
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post #10 of 114
11/28/08 at 5:59pm
Quote:
Originally Posted by Jeremy W View Post

I've seen it on my HR20, HR21, and H21. It's not the equipment on our end, it's DirecTV. I've never posted about it because it's not really THAT big of a deal to me, but it's definitely there.

Ive seen it, it happens occasionally
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post #11 of 114
11/28/08 at 7:11pm
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KABC - West Coast ABC HD MPEG4

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post #12 of 114
11/28/08 at 7:47pm
I have been seeing this issue on both ESPN's for a long time now, ever since it was launched in MPEG-4. I see it alot more than every 30 minutes though, more like once every couple minutes. Tonight Im seeing it on the Lakers Dallas game at least once a minute actually.

I never really recognized it as a frame shift as stated by the OP until it was pointed out though. Before tonight I just saw it as a hiccup/glitch in the video. Tonight I can clearly see the frame shift just as pictured in the stills by the OP.

I have been thoroughly annoyed by this issue for a good 6 months now, and I am amazed by the lack of any discussion regarding these issues. Dont understand how people cant see it. Ive never looked at any D* HD setup without seeing it since the ESPN's went MPEG-4. This would include my setup and at least 5 other setups off the top of my head.
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post #13 of 114
11/28/08 at 7:58pm
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WYNW - Fox East HD MPEG4 Channel 398 DTV Special

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post #14 of 114
11/28/08 at 8:04pm
Thread Starter 
Quote:
Originally Posted by guffy1 View Post

I have been seeing this issue on both ESPN's for a long time now, ever since it was launched in MPEG-4. I see it alot more than every 30 minutes though, more like once every couple minutes. Tonight Im seeing it on the Lakers Dallas game at least once a minute actually.

I never really recognized it as a frame shift as stated by the OP until it was pointed out though. Before tonight I just saw it as a hiccup/glitch in the video. Tonight I can clearly see the frame shift just as pictured in the stills by the OP.

I have been thoroughly annoyed by this issue for a good 6 months now, and I am amazed by the lack of any discussion regarding these issues. Dont understand how people cant see it. Ive never looked at any D* HD setup without seeing it since the ESPN's went MPEG-4. This would include my setup and at least 5 other setups off the top of my head.


Thats why I searched several sites trying to find any reference to it before I started a thread - and was somewhat amazed that there was not a thread - only scattered references in different threads to hickups.

Quite frankly, I don't know how long this has gone on - I would often see a flash shifting....and never knew what it was - until I decided to get to the bottom of it this week.

I was able to document it on different receivers and sets - even at different output resolutions - which is all things I wanted to look at prior to posting.

What I was really curious is how widespread is this on the LIL HD ABC/FOX in the 100 or so markets.

Also, I watched KABC-DT 6pm News and World News Tonight for an hour and never saw it once - but as can be seen, it was clear earlier in the today as witnessed by the evidence.

Thus you are correct - you can go for an hour and see nothing - and then see it several times in a half hour. No Rhyme or Reason.

On average I see it 1 and at most 2 times per hour - and I agree with Jeremy that it wasn't something that piqued my interest so much as to punch the TV screen as it is only 1 frame out of 60 in a second - but it clearly is noticable.
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post #15 of 114
11/28/08 at 8:56pm
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WABC-DT News - MPEG4 Channel 396 ABCHD East


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post #16 of 114
11/28/08 at 8:58pm
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Quote:
Originally Posted by TVOD View Post

It looks like the luminance shifts horizontally but the color stays centered. In the top image image the shift was to the left while the one on the bottom was shifted to the right. I tried re-sizing the images to 720p and then shifting the bottom part of the image luminance only. While there is some ghosting remaining due to Y/C crosstalk of the capture process, it gets back much closer to normal:

Both took about 70 pixels of shift. As the images look to be somewhat zoomed from optical capture, I would guess the actual shift is around 64 pixels, or around 4 macroblocks.

Notice the ESPN shift is to the left where all others are to the right.....
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post #17 of 114
11/29/08 at 5:06am
It is interesting to that this is being seen on the national channels and I have seen it on the national channels with my own setup. Locally, I haven't seen it on LIL channels (don't watch that much ABC, but I may start to see if I am seeing there yet), but I have been watching for it on my station.

A thought does come to mind that if the vintage of the MPEG4 encoder has anything to do with it. In my own stations case, we went live back in late 2006. The stations listed now, particularly the 390 stations, are all recent additions with later equipment.

i am not saying you wont see it on LIL channels, but on MY station, LIL, I am not seeing it, yet (and I hope not to). So I don't know if this has to do with a software upgrade, equipment vintage or what but it looks to me, this is an issue D* is going to have to get a handle on and soon and I will keep watching on my station to see if it starts to show up.
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post #18 of 114
11/29/08 at 9:00am
Quote:
Originally Posted by BeachComber View Post

Notice the ESPN shift is to the left where all others are to the right.....

ESPN is the only one that isn't sourced from a broadcaster in these examples. Are there other cable/sat only 720P channels with this issue?

D* appears to be using Tandberg MPEG4 encoders. This article says:

"US network ABC says it will, from this coming Monday, shift its HDTV distribution signals from MPEG2 to MPEG4, using compression and transmission kit from Tandberg Television. DirecTV has also committed to Tandberg kit for its HD expansion...

DirecTV has also selected Tandberg’s latest MPEG4-AVC HD encoders for its local-into-local high-def expansion. DirecTV has chosen Tandberg’s newly released EN8095 encoders, part of the EN8090 MPEG-4 AVC SD/HD encoding family."

We don't know if the encoders are the source of the problem, but if they are I wonder if ABC will be affected? I think they are still using the MPEG2 distribution.
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post #19 of 114
11/29/08 at 9:22am
I havent seen this issue on my LIL out of Green Bay at all. There are other issues with my LIL, but not the frame shift issue.

What I see on my LIL alot is the Brrrrriipp problem that has been discussed over at DBSTalk.

Also, just to back the OP regarding the frame shift, I do not see these issues on 1080i channels at all. It does seem to be 720p specific.

Also I would just like to say that I have made numerous calls to Directv about these issues, and Ive had 2 service calls regarding these problems as well. They have replaced all my cabling and my multiswitch and my LNB's, all to no avail.
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post #20 of 114
11/29/08 at 9:29am
Quote:
Originally Posted by TVOD View Post

ESPN is the only one that isn't sourced from a broadcaster in these examples. Are there other cable/sat only 720P channels with this issue?



What other channels would fall into this category? I believe NatGeo and the 720p RSN's would be the only other channels arent they?
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post #21 of 114
11/29/08 at 11:46am
Wouldn't ABC Family, Disney, Toon Disney and Fox News fall under this?
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post #22 of 114
11/29/08 at 11:53am
Call me naive, but I'm surprised that HD in a general sense still exhibits such hiccups as those discussed in this thread, lip synch, etc.--whether a D* issue or HD tech in general.

At what point does HD have to exist long enough that these things are very rare if not non-existent?
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post #23 of 114
11/29/08 at 12:04pm
Quote:
Originally Posted by MikeKlim View Post

Call me naive, but I'm surprised that HD in a general sense still exhibits such hiccups as those discussed in this thread, lip synch, etc.--whether a D* issue or HD tech in general.

At what point does HD have to exist long enough that these things are very rare if not non-existent?

These problems were all non existent when I had E* and Charter HD. Were it not for my 2 year commitment I would go back to the pathetic Charter HD lineup in a heartbeat. I would much rather be lacking in quantity than quality.
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post #24 of 114
11/29/08 at 12:11pm
Quote:
Originally Posted by NetworkTV View Post

Wouldn't ABC Family, Disney, Toon Disney and Fox News fall under this?

Yep, all 720p channels. I dont have any of these channels in my favs, so I wasnt aware they were all 720p.

Ill try watching some of these channels today and see if I see the issues...
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post #25 of 114
11/29/08 at 12:21pm
Quote:
Originally Posted by MikeKlim View Post

Call me naive, but I'm surprised that HD in a general sense still exhibits such hiccups as those discussed in this thread, lip synch, etc.--whether a D* issue or HD tech in general.

At what point does HD have to exist long enough that these things are very rare if not non-existent?

The problem is, the technology keeps being changed just a little bit just about every month as things get more efficient, cheaper or more complicated. Adding a new video codec to the mix makes it worse. There are so many systems in the chain now (including encryption), it's a wonder anything works at all.

Even worse, a lot of stuff is software based instead of solid state hardware. That introduces the potential for a single line of bad code to really screw things up with a lot of potential for the cause to be hidden.

Don't forget, it was years before they got black and white TV working with any sort of reliability or standard of quality.
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post #26 of 114
11/29/08 at 12:24pm
Quote:
Originally Posted by NetworkTV View Post

Wouldn't ABC Family, Disney, Toon Disney and Fox News fall under this?

I have seen it on FNC. I can't remember if I have seen in on FBN or not.
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post #27 of 114
11/29/08 at 1:10pm
I had noticed this on both DVR's HR-20 and HR-21. Had not narrowed it down to only 720p sources. Thought I was seeing things, as it had kind of a "Fight Club" look to it, where only one or two frames were off.
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post #28 of 114
11/29/08 at 1:41pm
I've seen it on Fox Sports Detroit.
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post #29 of 114
11/29/08 at 3:53pm
Thread Starter 
Quote:
Originally Posted by guffy1 View Post

These problems were all non existent when I had E* and Charter HD. Were it not for my 2 year commitment I would go back to the pathetic Charter HD lineup in a heartbeat. I would much rather be lacking in quantity than quality.

You were lucky - Atlanta LIL is a lip sync, frame dropping mess via E*.
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post #30 of 114
11/29/08 at 4:29pm
There was a mention about ABC and MPEG4 delivery to the Affiliates. This has not happened but will next Feb or whenever they get all the affiliates Sat Receivers changed out. It is all Tandberg. Today the HD is still on the same RX with QPSK as has been the case for years. Today the SD is back on QPSK with 3 channels per transponder.

Lets keep our fingers crossed and hope the next generation of ABC MPEG4 delivery to the affiliates will be smooth.
JStigler
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