Pixelation

[trublue]

Soon after getting Virgin media installed in late December I wrote a few lines in this forum comparing virgin with sky and saying how pleased I was with everything.But I'm started to wonder whether I was looking at the picture quality through rose tinted glasses,because I have been having problems with pixelation ever since I wrote those Lines.They may have been there from the install date but I never noticed a thing until a week or so later.I put up with it for a couple of months and then rang CS.They checked to see if anything was wrong there and then and she said everything looks fine,but I'll send an engineer out to check your box.He duly came,he didn't bother looking at the snippets of TV I saved for him to look at to prove my point.All he said was that the SA box was fine,but I'll swap it for a Samsung if you want.So he changed it over,but the pixelation is still prevalent.It's not a massive amount,but it just pops up when there is dark area on the screen,fast moving scenes,fire,or water motion(as in Perfect Storm).The HD channels are better but just now and then a get a little bit of pixelation.Am I being too critical?Does anyone else put up with this problem or is your picture perfect?If they can't found a problem,how can they fix it?Will they keep on swapping boxes until the problem disappears.Can someone please offer any advice.To cap it all, I have had the email to order Tivo,but I can't warrant the cash outlay when the pixelation will probably be evident in Tivo.

[spiderplant]

I think you are seeing the limitations of MPEG encoding. There's always a limit to the picture complexity that can be encoded, and things with lots of random movement like explosions and moving water show it the most. It's unusual to see it on HD, but it can still happen.

All I can suggest is to try adjusting your TV settings, and maybe sit a bit further from the screen.

[alexcopeland]

I have found that mid to low end LCD HDTV's display just as you describe. Higher contrast ratios and better processors in mid to high end HDTV's will produce better picture quality. What HDTV do you have?

[trublue]

Thanks gents.Spiderplant,I take it that Sky doesn't use Mpeg encoding,because I had no pixelation with them?But I will try your suggestion and have a look at the TV settings.

alexcopeland,I have a Sony Bravia KDL 32S55,(only720p)which was alright when viewing with sky as stated above.If it is caused by low end TV's it must be wide spread problem surely?

Do you think people just put up with it?

[Lew]

It sometimes helps to go into the picture settings on your TV and turn off all picture processing as that tends to accentuate any flaws with broadcast TV.

[OLDGOLD]

Originally Posted by trublue

Soon after getting Virgin media installed in late December I wrote a few lines in this forum comparing virgin with sky and saying how pleased I was with everything.But I'm started to wonder whether I was looking at the picture quality through rose tinted glasses,because I have been having problems with pixelation ever since I wrote those Lines.They may have been there from the install date but I never noticed a thing until a week or so later.I put up with it for a couple of months and then rang CS.They checked to see if anything was wrong there and then and she said everything looks fine,but I'll send an engineer out to check your box.He duly came,he didn't bother looking at the snippets of TV I saved for him to look at to prove my point.All he said was that the SA box was fine,but I'll swap it for a Samsung if you want.So he changed it over,but the pixelation is still prevalent.It's not a massive amount,but it just pops up when there is dark area on the screen,fast moving scenes,fire,or water motion(as in Perfect Storm).The HD channels are better but just now and then a get a little bit of pixelation.Am I being too critical?Does anyone else put up with this problem or is your picture perfect?If they can't found a problem,how can they fix it?Will they keep on swapping boxes until the problem disappears.Can someone please offer any advice.To cap it all, I have had the email to order Tivo,but I can't warrant the cash outlay when the pixelation will probably be evident in Tivo.

I joined VM a couple of months ago and I noticed exactly the same things that you have. Oddly though, for me things were worse to start with and have improved over the last few weeks, but there are still some channels that seem worse than others. ITV3, ESPN America, BBC2 seem the worst culprits, but I can't say I have watched every channel.

Of the HD channels, BBC One HD is the one that I have the most problems with, but do get the odd glitch every now and then on most of them (which is something I never experienced with Sky HD). But BBC One HD aside, the glitches are very few and far between on HD.

I find some of the On Demand stuff poor quality too, but then some of it is really good. It seems a bit of a mixed bag, to be honest.

I can't see it being down to the TV as the picture through Sky was quite a bit better and that was connected to the same TV.

[Lew]

Originally Posted by OLDGOLD

I joined VM a couple of months ago and I noticed exactly the same things that you have. Oddly though, for me things were worse to start with and have improved over the last few weeks, but there are still some channels that seem worse than others. ITV3, ESPN America, BBC2 seem the worst culprits, but I can't say I have watched every channel.

The picture on ESPN America seemed to get noticeably worse when they launched their HD channel. I assume it's to get people to pester their TV providers to carry the HD version.

[OLDGOLD]

Originally Posted by Lew

The picture on ESPN America seemed to get noticeably worse when they launched their HD channel. I assume it's to get people to pester their TV providers to carry the HD version.

Yeah, you're probably right. But it's a bit tough on the people whose TV providers don't seem willing to carry it.

[spiderplant]

Originally Posted by trublue

Thanks gents.Spiderplant,I take it that Sky doesn't use Mpeg encoding,because I had no pixelation with them?But I will try your suggestion and have a look at the TV settings.

Sky do use MPEG. In fact for many SD channels, VM take the encoded stream off satellite and send it down the cable, so it's exactly the same data. I can only think you either used a different connection to the TV, or the Sky box was blurring the video so the blocks weren't as obvious.

OLDGOLD: I suspect you may have a signal problem. Could be worth giving VM a call.

[alexcopeland]

I've had a look at the spec of your HDTV and would suggest turning off the Digital NR feature and see if this helps improve the picture quality. I would also recommend you spend some time adjusting the picture settings namely the contrast and sharpness options as this might be revealing poorer picture quality. Is recommend you have you set top box set to 1080i.

[trublue]

spiderplant said

Sky do use MPEG. In fact for many SD channels, VM take the encoded stream off satellite and send it down the cable, so it's exactly the same data. I can only think you either used a different connection to the TV, or the Sky box was blurring the video so the blocks weren't as obvious.

The only difference in connection terms is the HDMI lead.Thanks anyway for your reply.
alexcopeland
The set box was set at 1080i but I changed it to 720i when I noticed the pixelation problem.I'll change it back and look at the TV settings.
Thanks for the help everyone.

[OLDGOLD]

Originally Posted by alexcopeland

I've had a look at the spec of your HDTV and would suggest turning off the Digital NR feature and see if this helps improve the picture quality. I would also recommend you spend some time adjusting the picture settings namely the contrast and sharpness options as this might be revealing poorer picture quality. Is recommend you have you set top box set to 1080i.

Are the issues likely to be caused by contrast and sharpness settings being too high or too low?