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1080p: un po' di chiarezza (o forse no...)

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Digital-Forum Silver Master
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5 Aprile 2004
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C'è un po' di confusione sui formati HDTV? Pare di si. Soprattutto perché gli schermi attualmente in circolazione, pur se "HD Ready", non sono in grado di visualizzare segnali in 1080p. Significa che sono schermi "HD Lite"??
Gli amici di HDTVUK hanno posto il quesito a Toshiba, Sony e Philips.
Di seguito vi riporto domande e risposte, ovviamente in inglese...

Are 1366x768 pixel sets true HD?
Ian Rea - Toshiba UK Product Manager - Flat Panel TV
True HD is not the best terminology to use. There are 2 types of HD broadcasting, 720p and 1080i. So, yes a 1366 x 768 panel is capable of displaying 720p HD signal. A 1920 x 1080 panel on the other hand is naturally capable of displaying a "Full" 1080 HD signal being broadcast. I believe the best way to explain is the differences, is simply "HD ready", & "Full 1080 HD Ready" as there is no bigger HD signal than 1080 - hence the "Full" expression.
Danny Tack, Product Marketing & Strategy, Philips Flat TV
If they are HD ready, then yes they are true HD sets. Consumers in store are going to see a picture that is between three and four times sharper than their current set, so they will see high definition pictures. At Philips we do not believe that pixel count is the most important issue. Having enough picture processing power, and processing accuracy, is three times more important than just increasing the number of pixels. In fact, if the processing isn’t good enough, problems will be magnified by adding more pixels. In US, where HD is already more established, there has never been an issue in the trade and with consumers, that 768p panels would not be sufficient for HD sources.
Sony

Sony has a range of television sets in the UK market today with a resolution of 1366x768 (WXGA). Within the TV industry there is a common definition to describe a TV that can be called ‘HD Ready’. All Sony BRAVIA TV’s 26inch and above have HDMI, Component inputs and 768 lines and are therefore referred to as ‘HD Ready’.

How will 1366x768 pixel sets work with 1080p signals from Blu-ray etc?
Toshiba
If Blue-ray is actually capable of 1080p (as it all seems a myth at present!!), or even if a 1080i signal is being received by the 1366x768 panel, then in simple terms the "scalers" in the back of the set will down-convert the image to fit to the panel resolution of 768 lines. By using a very complex algorithm sequence the scaler will systematically crop the image to fit the lower resolution panel. In the same way that "down conversion" happens, up-conversion also occurs, so if a 1080 panel is receiving a 720p image, the signal will be "oversampled" to fit the big screen resolution has to occupy - again all completed by very complex algorithm sequences.
Philips
There are two versions of 1080P – 1080P/50 for which it’s unlikely that there will be any native content available in the foreseeable future and 1080P/24 which is likely to be adopted by the movie industry for Blu-ray. Blu-ray will upconvert 1080 50i to 50p resulting twice the pixel rate of today’s 1080 50i, in this case we recommend that viewers not use the upconverted 1080 50p but install the output mode on the Blu-ray to 1080 50i and leave the PQ processing (including upscaling to 1080 50p) to the Flat TV. 1080/24p carries the same pixel rate as a 1080 50i source, which automatically means that today’s hardware can handle it, but this format (film) will add judder.
Sony

On a Sony BRAVIA TV a technology known as ‘BRAVIA Engine’, contains a suite of imaging processing technologies that acts as a total digital processing studio carrying out multiple enhancements on every frame of signal in real time to deliver the appropriate picture to the LCD panel from a variety of sources including Blu-Ray.

Is there a real benefit to consumers for buying a 1920x1080 set?
Toshiba

Yes !! Our Toshiba 42 & 47WLT66 have an "Exact Scan" mode that allows a 1080 broadcasted signal to be processed by the panel in the original broadcasted format, ie, no scaling of the original image occurs and no loss or cropping of picture and no loss of picture quality. I am lead to believe that BskyB will broadcast most if not all Nature programmes and discovery channels in 1080.
Philips
If the processing is good enough, then more pixels will mean a sharper picture. It’s important to understand that all pictures are scaled (because in reality we need to cope with all kind of tolerances on signals and support overscan in the picture ) and if scaling is applied it will be to all of the picture. Currently 95% of signals that are input require scaling because of overscan, this includes 1080i inputs for 1080 sets. So again the key factor remains, how good is your processing?

Will Sky's HD pictures look better on a 1366x768 pixel set?
Toshiba
In relation to the above, there will be advantages and disadvantages. If you are a keen sports watcher then a 768 panel is going to be ideal, as again, we are lead to believe that BskyB will broadcast all sporting events in 720p, so this resolution ideally matches the screens 768 resolution. The lower broadcasting format will occur as it will help reduce the bluring that is sometimes seen in fast moving images. If you are a keen lover of David Attenbourogh and History programes, then 1080 would be more suitable as they will be broadcast in 1080, and referring to my explanations above, if you have a Toshiba 1080 tv, then there will be no loss of picture using the Exact scan mode. If you have a 768 panel, down conversion will occur by the scalers in the chassis of the tv.
Philips

Again, we’d have to refer you to the quality of the sets picture processing as being the key issue rather than the screen’s pixel count. But generally, Sky images shouldn’t be any better on a 1366 x 768 set.
Sony

When Sky transmits in HD there will be a mix of content in both 720p and 1080i*. All Sky HD pictures will look better on a 1366x768 TV compared to a standard TV resolution panel because of the greater detail given by the number of pixels. A further benefit is offered to consumers deciding to purchase a 1920x1080 TV due to the increased number of pixels, which will deliver a higher resolution given the appropriate content being delivered to the TV.

What are the key issues for improving the quality of HD TV sets?

Toshiba

I dont believe there are any key issues to improving the quality of HD sets. As I am hoping you will agree at our show last week, we were displaying various HD formats (both 720p & 1080i) via different formats, and they all looked fantastic. If we break it down a little, a 1366x768 panel has 1,049,088 pixels to display any image, while a full 1080 panel has 2,073,600 pixels, just shy of double the amount of pixels. The additional pixels equates to greater depth and clarity in the picture.
Philips

At Philips the majority of our work has been based on LCD technology. For us, given all things being equal, LCD will always be sharper, brighter and whiter than an equivalent plasma set. So we have been working on LCDs problem areas of motion blurring and black levels. Our major innovation in 2006 will be the Clear LCD feature which adopts a new lamp technology – HCFL - that allows both a dimmable and scanning backlight. We believe this technology finally addresses the problems of LCD and means that we can categorically state that LCD now offers the best picture quality. Our other area of development has been on processing quality. In our latest sets – with Pixel Plus 3HD - processing is entirely in the digital domain and without any downscaling of the input signal.
Sony

Sony’s aim is to create products that let the consumer enjoy creating, editing and viewing HD content to its full potential. Within Sony BRAVIA HD TV’s we are constantly bringing to market improvements in picture quality. Sony BRAVIA HD TV’s employ the latest 7th Generation LCD Panel production combined with Sony’s unique technologies gained from years of experience producing broadcast equipment including broadcast HD cameras. A technology known as ‘Live Colour Creation’ is a feature of Sony’s new V Series range of BRAVIA TV’s launching in May. ‘Live Colour Creation’ combines circuitry, backlight and a colour filter to create a picture, which is more realistic, and a natural fit to the human eye, the result is deeper greens and deeper reds. The consumer benefits from seeing 30% more colour with this ‘Live Colour Creation’ feature. Sony would also recommend that consumers invest in good quality cabling including using an HDMI cable for their primary HD source. Of course HD is only really brought to life with Digital Surround Sound as the ideal backdrop to the stunning picture quality that HD delivers.
 
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