Whenever i watch moving sport especially football I experience much poorer pictu
What you are seeing is one of the two problems that are well know about the "MPEG-2" system that is used to encode digital TV.
Because of the way the system works, horizontal movement across a crowd requires a disproportionate large amount of data to encode.
Because the bandwidth on Freeview is so limited, and as most broadcasters have decided to have more channels rather than better quality pictures, on most channels the bandwidth is so limited that the effect you see, a blurry mass of blocks is visible.
The sceptical will say that this is simply an excuse to sell you HDTV equipment and channel packages.
The other problem you will see is when strobe effects are used - this will often look like very large black and white boxes.
If these effects trouble you, do not go out and buy yourself a massive TV as they will be simply much clearer to you.
10:53 PM
Hi,the definition of ghosting is a secondary image attached to the video which can be from indifferent
reception on analogue,mismatch of input circuitery,noise, too many units in line,poor cable where the
signal gets reflected back and forth in the cable.On analogue,there were cases in London where the
ghosting wasn't fixed ,this was called multipath.
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nicholas's: mapN's Freeview map terrainN's terrain plot wavesN's frequency data N's Freeview Detailed Coverage
11:04 PM
As stated in my articles,mpeg 2 does suffer from stuttering or jerking effects particulary on fast motion
where there is insufficent bit rate to carry the video information but domestic equipment also has deliberate
noise added as per my previous articles and i have explained why.
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nicholas's: mapN's Freeview map terrainN's terrain plot wavesN's frequency data N's Freeview Detailed Coverage
11:25 AM
Over the past week or so, we have experienced an annoying problem with all of the HD freeview channels on our newly installed BT Youview box. Our signal strength and quality are very high (and solid) ;- 92% and 100%, respectively. However - very randomly - both of these measures drop instantly to zero, for a split second, then as quickly, go back to the high settings. This causes pixilation and/or freezing for any of the five HD channels we are watching. There is no consistency, it can happen three times in twenty seconds or not happen for ages. I can see from your information pages, that all HD channels are fed from the same MUX. I have also been told by BT that the problem is due to poor aerial reception, but we are struggling to accept this as we have no other issues with HD reception in the house. This problem has suddenly disappeared - today - for some reason. Any clues, advice or guidance please? Any help will be greatly appreciated.
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1:00 PM
Alan Burnham: Please provide a full postcode so we can see which transmitter you're using and where you are in relation to it. However some general advice based on your post is that you probably have too much signal which is overloading the tuner in your Youview box. This can be reduced by fitting an attenuator (see link below) which connects to the incoming aerial cable and reduces the level of signal being received. It may be worth getting 3dB, 6dB and 9dB attenuators which can be connected together if required to reduce the signal further if one on its own isn't enough.
6dB Coax Plug Inline ATTENUATOR: Amazon.co.uk: Electronics
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6:31 PM
Hi,everyone has refused to believe this, THIS IS DELIBERATE NOISE added by the manufactures of the freeview product to encourage you to buy the HD version,more money for them,its called expander noise,and is also found in sd cameras,if you observe the pictures on certain programmes,it is nothing to do with mpeg 2 encoding,if you don't believe me,switch yr box to the radio section and see how clean the picture.Really the manufactures should be proscuted for this but pigs will fly.The noise can be modified to suit the purpose and on digital programmes,its arranged to show blocking.Look at the picture when it freezes,it is different,if you dont want to believe me ,fair enough.......................On football,there is a lot of movement so it looks like a ghost image is there.Remember VHS,the outlines are spikey,same thing,done for copyright reasons.
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6:33 PM
I have told you the truth of the matter,if you can't accept it,TOO bad.
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nicholas: You blathered on about this eight months ago - and still nobody has a clue what your on about now.
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11:01 PM
Sorry mike ,i'm answering a question,but it isn't too difficult to understand this is deliberate noise added to the video output,if you're an english speaker you will know what the word ADDED means,sorry,its the only way i can explain,so no offence meant to anybody.
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10:36 AM
Nicholas:
I strongly suspect that what you are commenting about is a result of low bit rate transmissions, used by the broadcasters to cram more channels into the available space on the multiplexes. No TV manufacturer has the desire to make their product worse than others so they would not go to the expense of building in a system to do as you suggest - even if it were possible to differentiate between the content of different programmes. I compared the Freeview and Freesat transmissions for the recent Monaco Formula 1 race, containing loads of fast movement and transistions and on Freeview there was noticable jerkiness on fast pans but much less so on Freesat - I had two TV sets side by side which I don't usually have. That indicates that the Freeview transmission is more prone to a jumpy appearance during rapid panning, an artifact that was absent with analogue transmissions.
If your VHS recordeder did as you suggest, it was faulty. I worked on a range of VHS recorders since 1978 for a major TV rental company, so have a good understanding of how they worked and what went wrong.
I'm not sure what question you were trying to answer but I can't see any relating to what your saying.
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MikeP: Exactly!
Artifacts are just one of those things you get with a digital display - the more you pay and the more data you have, the less you get (see a cheap TV and an expensive TV next to each other and the difference in processing will become very clear). But even if you go to a multiplex cinema and look very closely at their 4K projection you will get a little bit of motion blur.
There is no 'deliberate noise' - no manufacturer in their right mind would do that, considering how much money they spend trying to get the noise out of the system and getting you to pay for it. Seriously, this is tin foil hat territory.
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