# why does my vip 622 pixelate?



## ragman757 (Apr 2, 2007)

i cant expalin what i mean but like compresion pixelation is what it looks to me.i have a 622 on a olevia 437 lcd tv via hdmi. i notice it mostly on hd chanels


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## ragman757 (Apr 2, 2007)

ps i notice it more on fast motion


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## Mr.72 (Feb 2, 2007)

welcome to HDTV

aka "high definition except fast motion"


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## ragman757 (Apr 2, 2007)

that sucks will it ever be for fast action to im a football fan guess it will suck this year


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## rice0209 (Oct 11, 2005)

Pixelation and fast action HD are not synonymous. There are many variables that go into it, but i have watched many, many HD programs that are fast action and do not have issues.

Some of those variables are the quality of feed. In my area, Kansas City, Fox has an excellent quality signal where as CBS had a horrible feed all tournament. 

Discovery HD is by far the best in terms of quality. I rarely see pixelation of any kind, unless weather related and it is by far the cleanest and clearest HD feed I have seen on Dish. 

My local NBC channels do not seem to have the correct equipment for broadcasting or rebroadcasting their High def signal as I constantly get pixelation and terrible SD/HD changeovers during commercial breaks. My sister, who also lives in KC has the exact same problems with her 622.


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## rice0209 (Oct 11, 2005)

Ragman,

What mode do you have your television set to? 480P, 720P, 1080i?


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## Mr.72 (Feb 2, 2007)

I have yet to see a HD program that does not do this with fast action. You pretty much notice it only on sports. I think maybe the live broadcast nature of the sports programs makes it tough (has to be encoded on the fly).

What on Discovery HD would have fast action, like a basketball game would?


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## ragman757 (Apr 2, 2007)

i have a tv its native resoltion is 768 p. so i set the vip 622 to 720 p .but i think i tryied 1080i to. also i never got that software update to 401 but i assume i wont get it then


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## whatchel1 (Jan 11, 2006)

rice0209 said:


> Pixelation and fast action HD are not synonymous. There are many variables that go into it, but i have watched many, many HD programs that are fast action and do not have issues.
> 
> Some of those variables are the quality of feed. In my area, Kansas City, Fox has an excellent quality signal where as CBS had a horrible feed all tournament.
> 
> ...


I get the same problem w/ the KC NBC that you do. I have emailed the news dept of the station. Reason for email to news dept is that the is no email address for both the engineering dept or the GM of the station. So I'm damn near going to spam them until the news dept tells the engs about my emails. I getting really tired of the pixelation for several minutes at a time. BTW my system is 1080i w/ a Panny 32" HD CRT. The setting of the monitor 720 or 1080 has nothing to do w/ the problem here. I have seen the problem with a talking head on the nightly news.


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## Mr.72 (Feb 2, 2007)

the setting of the monitor does not affect the broadcast stream. If it's pixelated, it's likely that way in the source material (that is, the data stream before it gets into your antenna) and not caused by your receiver or TV.

I think the reason it's such a problem with sports is that they have to encode it live, on the fly. While with a movie or another program, it may be encoded to MPEG-2 with a slower, less lossy procedure that cannot be done in real time.


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## johnsbin (Nov 14, 2002)

Digital displays are susceptible to motion blur. The more expensive digital displays are able to make some compensation for this problem but the low cost panels will display this problem the most. 

Then if you add signal compression on top of this and you are bound to see some digital artifacts in your picture, to include pixelation and motion blur.


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## rice0209 (Oct 11, 2005)

Discovery HD runs all sorts of programming with fast action. I have watched all sorts of auto racing documentaries as well as other types of programs. The blue Angels documentary also comes to mind. 

I also have watched baseball on my local fox channel and not noticed any pixelation of the image. To me, this has more to do with which channel is doing the broadcast and processing of the signal.

My question relating to his display was whether he was in 1080i or 720p. Some people commonly associate pixelation with the ghosting or blurring of images created by using an interlaced signal. As Johnsbin said, more expensive TV's have beeter processing of the signal and can overcome this, but more inexpensive units have difficulties translating the image correctly into the digital panel.

I run the 622 with HDMI to my 720P Hitachi projector which is a 3 LCD unit. I occasionally get pixelation, but it happens on fast or slow action shows. I think the general statement of "welcome to HDTV aka "high definition except fast motion" is completely false and you were misleading Ragman to believe that he will never get a good quality picture from his new hd set. 

Besides, many have had problems with pixelation on the 622. Pixelation can occur from a loss of data in the satellite transmission or pre and post processing in the studios, production semis, or even in the 622 or your monitor. There is a lot of processing going on and any one of these steps could be the culprit.


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## Mr.72 (Feb 2, 2007)

alright nevermind. if you have pixelation, you must have junk equipment, you're watching the wrong channel, it's in your head.

I'm sure I must be imagining things that every single HD basketball game I have ever seen that is not on ESPN is heavily pixelated on fast motion. Since that's like 95% of what I watch in HD, it's not really surprising that this is where I see it most. Maybe I need a Monster cable somewhere to fix it.


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## johnsbin (Nov 14, 2002)

Pixelation and motion blur are not in your head (technically since eyesight is rendered by the brain, it IS in your head) they are real digital display artifacts and they occur for several reasons to include the signal, the signal provider, the signal reception equipment, and the display equipment. We all experience these artifacts but if you are experiencing a lot of it, there are several problems you have to eliminate.

Cheap equipment does frequently contribute to degraded signal quality, but buying Monster brand overpriced products is not the only solution!


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## johnsbin (Nov 14, 2002)

To add an additional note here:

One source of pixelation is when a display must scale an HD signal to its native resolution. Scaling from 1080i to 720p will introduce pixelation to HD content, especially fast moving content. This is why ESPN captures and broadcasts in 720p, since the vast majority of HD displays were 720p devices. 1080i/p devices have started to make a dent in that but ESPN still runs at 720p. 

This signal is encoded in mpeg2 or mpeg4, which can also introduce digital artifacts like pixelation. mpeg4 is better about that than mpeg2.

So, if you are receiving 720p mpeg4 and you run it natively to a 720p device, you stand a good chance of having a great picture! The only problem you now face is the refresh rate of your display device. Cheaper LCDs might not have a fast refresh rate and could exhibit some motion blur, otherwise known as video delay.

This explains why Mr.72 has a great picture with ESPN, not so much elsewhere running 1080i.


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## rustamust (Feb 22, 2006)

I watched the entire final BB game last night on CBS OTA and did not have any pixilation on my Mits. 55" and its over 5 years old. 622 is one month new.


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## Mr.72 (Feb 2, 2007)

Which TVs are "native" 720p?

I don't know of one. LCD & Plasma are generally 1366x768 progressive and require scaling no matter what the source. Some newer ones are 1920x1080 progressive and don't require any scaling of 1080i. CRTs do not really have a native resolution like this.


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## ragman757 (Apr 2, 2007)

i find my diplay is not the probelm im not sure but id say no since hell i watched moviesd on old lcd monitors that had like a 32 ns refreashrate and never noticed it.id say its content


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## johnsbin (Nov 14, 2002)

Stretching to 1366 X 768 is not the same as scaling from 1080i. 

Rustamust: What res output is your 622 set for? Is your Mits CRT RPTV? CRTs are a completely different animal.


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## Mr.72 (Feb 2, 2007)

scaling down is easy. There's nothing to make up to fill in the gaps. Scaling up is what's much more difficult.

But anyway .... motion blur is not the same thing as pixelating. The pixelating is very clear and also very clearly not the display when you can pause the recording and play it frame by frame and clearly see the macro block construction. It's obviously present in the data stream that has been recorded in the 622 whether it is from OTA or from sat input. Doesn't really matter. But this definitely rules out the display as any part of the problem.

I think most LCDs are sub-16ms response time these days (who can be sure, there are like 200 brands). That's fast enough to handle 720p60 without any artifact and over 2x the rate needed for 1080i.

I guess you are not open to consider the idea that the source encoding can be 100% of the cause of pixelation?

Anyway, to the original poster, IN MY OPINION and IN MY EXPERIENCE pixelation is a common issue that occurs in nearly every HD program with fast motion, particularly sports that are encoded on the fly in 1080i.


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## johnsbin (Nov 14, 2002)

All 720p devices have to scale UP 1080i content. That's right - UP. That's because 1080i is not 1080, its 540x2. So you have several steps involved such as scaling up to 1080p then back down to 720p and do all this on the fly immediately. Your scaler is the source of your pixelation, on top of any artifact presented by the source.

I'm very open to source capture and encoding causing pixelation and other digital artifacts. You can plainly see it when the broadcaster cranks up the compression when the field goes to wide view versus when there is a closeup on a player or especially the commentators and they want to present the best picture possible.

But I'm not going to subscribe to "it has to be the source since I can't see how it could be any of my stuff" philosophy. Sounds too much like its always someone else's fault.

You said yourself ESPNs 720p looks better than someone else's 1080i on your equipment. 

It will be nice when all points in the process are improved. We win!


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## rustamust (Feb 22, 2006)

johnsbin said:


> Stretching to 1366 X 768 is not the same as scaling from 1080i.
> 
> Rustamust: What res output is your 622 set for? Is your Mits CRT RPTV? CRTs are a completely different animal.


622 is set for 1080i and its a CRT RPTV. I love it and the 622 together.


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## podder320 (Mar 4, 2007)

I think this thread has a lot of different answers because the original poster wasn't clear in what he meant by "pixellation." That word can describe a large family of image quality problems. Without more information, everybody projects his own meaning onto it.

Here's an example from the recent NCAA tournament on CBS: when I watched games on KPIX-San Francisco from the Dish, there were often bad macroblocks across about 25% of the frame shortly after the arena's photo strobes went off. (Whole-image brightness changes require lots of bits in MPEG.) When I switched to my OTA antenna to watch the same game on the same channel (still through the 622), this never happened. Conclusion: it was introduced in the MPEG stream during the recompression / bit budgeting that was happening in Denver. I wrote to [email protected] about it and got a form letter in reply about trading off MPEG quality vs. "increased customer choice and value" (that is, more channels).

Ragman, can you be that specific about what you're seeing, so we have some hope of offering an explanation?

For example: "I can record and play back the effect I'm seeing and it appears even on freeze-frames." That would eliminate motion artifacts in your display.

"I see large colored blocks that stay behind when things on the screen move. They clean themselves up after a second or two." That would suggest signal dropouts or transient errors in the data stream. It could be a problem in your rooftop dish or the cables running to your 622.

"There is a halo of bright dots around small, high-contrast objects." That's an MPEG compression artifact based on the bit budget that E* assigns to the channel you're watching. Not a defect per se, but if you turn down your TV's brightness and sharpness settings it might be less noticeable.

...any of those sound familiar? Or something else? Can we buy a vowel?


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