Originally Posted by audioNeil
I realize I'm resurecting an argument over a week old, but as a person who actually gets paid to write scaling algorithms, I can give some information.
A scale-up algorithm using at least a 4x4 Kernel can give scaling that loses at most 3% of its contrast at maximum resolution. My experience is that such algorithms are exceedingly sharp at the slightly lower spacial frequencies, and can act like a slight sharpening filter, which you may or may not want. The tuning of the algorithm to provide the highest contrast at full resolution, without adding noticeable sharpening artifacts is the goal. There is no obvious stairstepping artifacts, or moire.
A simple 2x2 bilinear scaling kernel loses about 14% of the its contrast at maximum resolution. It also adds stairstepping artifacts on angled edges. However, it doesn't have any sharpening effects. If anything it has a slight softening effect. It can add slight moire, but only in extremely rare situations (high frequency test patterns).
The quality of scale-up from 720p to 1080p depends on the design of the filter. I remember seeing 6x3 or 5x3 size kernels advertised in the past, which will do a good job in one direction (probably the rows), and a poorer job along the verticals. Any kernel that has 4x4 or better is going to be awesome, provided it doesn't add too much extra sharpening (though you might be able to compensate by turning down the TV's sharpening setting).
I would much rather have a display that has to scale-up some signals, to one that has to scale-down others. It makes no sense to believe that because the eye can only resolve 720p signals at 10 feet on a 50" screen, that a 720p-native display is best, even for 1080 signals. This is crazy. Unlike the scale-up process, scale-down is both a lossy process, and extremely difficult to do without artifacts! Moire is almost a given -- it is exceedingly difficult to prevent in certain scenes and test patterns. Stairstepping artifacts are a possibility. And, if the processing tries to minimize moire, it can usually only do it by further softening the image.
No, use the highest resolution screen. If your eye can't resolve it, your eye will be the ultimate image processor, giving you an artifact-free view at the maximum resolution of your visual perception.
I also think that people who quote "maximum eye resolution" numbers don't understand that these aren't a hard limit. People's visual acuity are different, and many people will be able to see beyond this. Resolution describes the ability of the eye to distinguish 2 points of light, separated by an angular distance, as 2 distinct objects. When a person hits the resolution limit for his/her eyes, it does not mean that the 2 points of light look like one point. It means that they can no longer be disinguished as separate, but they may still look elongated, with a slight darkening between. Your eyes will be able to see the fact that they aren't a perfect single point for angles smaller than the resolution limit.
If we take this back the TV, our visual system is able to perceive things about a picture beyond the standard 60 arc seconds. It is quite easy for me to look at the planet Venus, and see that it is not a circular shape when in crescent. The size is about 60 arc seconds at that point. It is clearly not a point, and yet that is at the limit of resolution. This limit is not a hard number! It is also possible for me to notice that a 1080p panel has more natural edges, better high-rrequency contrast, and lack of any rainbow effects compared to a 720p panel. The differences may not be night and day, but they can be there. Also, sometimes kids sit on the floor and watch the screen. I want the TV to give the best possible picture at all viewing positions.
I also want bigger than a 50" TV. So, bring on the 1080p large-size plasmas! I'm waiting to buy one.
First, thank you for the kind supportive comments that came in after all seemed to find respect for the other side having it's moments.
They just couldn't let it be after all agreed, this will prove my point on how far they will go to try to prove 1080p resolution supremacy.
" It is quite easy for me to look at the planet Venus, and see that it is not a circular shape when in crescent. The size is about 60 arc seconds at that point. "
I will file this post forever.
I can tear your argument apart about what you called down scaling... first of all 1080i to 720p is really cross conversion, as some 1080p proponents try to call it down conversion. We will get back into filler pixels.... ETC.
You will get the best 480i signal you ever seen from a 720p or 1080 signal, (converting 1080 or 720p to 480) is far better than seeing 480i in 480i. You can down & cross convert, never fully up convert as up-scaling systems to 720p or 1080 have been proven to never match the actual true 720p or 1080i signal. Your point is flawed.
You're just re-hashing a 7 pages back debate.
The human eyes is always the deciding and conclusive factor rather than what is made up on paper or demonstrated by other illustrations.
What can be demonstrated with many pixels and other statements on paper proved to be a non factor in relation to the human eyes in conclusive tests.
Side by side tests are conclusive and shown no differences with the 1080i signal going into the 1080p next to the 768 one.
"We've done side-by-side tests between two 46-inch LCD HDTVs, one with 1366x768 resolution and the other with 1080p resolution, using the same 1080i source material, and it was extremely difficult for us to see any difference. It becomes even more difficult at smaller screen sizes or farther seating distances--say, more than 1.5 times the diagonal measurement of the screen."http://www.cnet.com/4520-7874_1-5137915-1.html
When they were up close they said it was
"was extremely difficult for us to see any difference"
As they moved back to 6 and a half feet (1.5 times the diagonal measurement of the screen) it became even "more difficult" than what they said was "extremely difficult"
"The good news is that amongst the 1080p sets they used (the 47-inch Westinghouse and the 50-inch Pioneer) the level of detail was "virtually identical." However, when they compared the image to sets with lower resolutions, they noticed it was harder to pick up on the differences in detail. Overall, they concluded it would be "practically impossible" to tell the difference between the image on a 1080p vs a 1080i or 720p. "http://gizmodo.com/gadgets/1080p/108...-it-213983.php
"Surely, you will not perceive any difference in image detail between 720p and 1080i/p HDTV material on the smaller sets from 10-feet away. You need to sit closer and feed your 1080p HDTV set with a good quality HD source to possibly start to see any difference."http://www.practical-home-theater-gu...080p-HDTV.html
As it was agreed that there are times that 720p is clearly better, to reach as far as you did simply proves my point on how far some 1080p proponents will go.
As far as resolution... the eye can pull in more, but there is a limit when you're talking about the resolution within a certain diagonal area at certain distances.
Once again at 10 feet, the pixels are bigger on a 720p set, which means the max resolution of the eye will appear better at this distance.
"No, use the highest resolution screen.
LOL... then make sure you get the 2160p set when it comes out...http://en.wikipedia.org/wiki/2160p
That will give you a true 2160p with all signals going into it...LOL. It will do wonders for the the two fields of 240 (480i).
"If your eye can't resolve it, your eye will be the ultimate image processor, giving you an artifact-free view at the maximum resolution of your visual perception."
A statement lacking any professional verification sources.
Again the highest resolution screen uses filler pixels to many signals and does not fit the 720p signal like a glove as 720p set, and as I have quoted in many professional conclusive tests, cross conversion did not show any differences with 1080i signals on the 720p set next to the 1080p one at average distances.
Your above quote is not proven in fact and goes against the facts and results of the demonstrative and professional side by side tests that I have provided with links. All your doing is bringing back the same arguments from 7 pages back that went no where.
Your comments opinions and experiences such as "It is also possible for me
to notice that a 1080p panel has more natural edges, better high-rrequency contrast" or "My experience is that"
....are bias and opinionated and and go against the many professional and conclusive side by side tests.
To go as far as mentioning kids sitting on the floor proves how far you will reach...
if you read through the thread it was agreed that 1080p sets will see benefits with a 1080p signal within 6 feet.
Also as far as bigger sets, lets not get into the facts about loss of quality when pixels get stretched for bigger screens. Do some research on that.
Again your reach was a classic, and proves my point once again, and this is not a knock to those to whom we all agreed to disagree.
Nice try... or reach. To be honest I never thought one would reach that far.
If you really think a neutral person reading this can't see that, makes you extremely comical. As I said this to another post before....and as we seen some of the comments starting to come in after both sides appeared to respect the other side.
Because it obvious, it would be more of an insult for any 720p proponent to answer you back after this point.
"My eye happily resolves 1080p well at 8-9 feet, and I can't imagine running my PC desktop or my BluRay movies at 720p!"
It is amazing how 1080p proponents resolve 1080p at 8 feet, I guess they get vision that goes against all the math facts quoted from multiple sources once they buy a 1080p set. This is a classic example of... stop B...Sn yourself!
Taking they are talking about a 50 inch set.
Please see the chart below as to when certain resolutions START to become noticeable!http://www.carltonbale.com/wp-conten...tion_chart.png
Running Blue Ray... Hummm if you RUN the player at a 1080 setting, the 720p set will display it at the max eye resolution for 10 feet if you have a 50 inch set.
On a closing note, I would like to say to all the 1080p proponents that have agreed to disagree, that I do not hold his comments as reflective of your views.
We have found respect for each other moments, without literally having to reach for Venus!