4k by 2k or Quad HD...lots of rumors? thoughts? - Page 22 - AVS Forum
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post #631 of 3692 Old 01-25-2012, 09:41 AM
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There have been some discussions in this thread about how to deliver 4K content without "unmanageable" bit rates.

Recently MIT researchers revealed new faster compression algorithms.

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The faster-than-fast Fourier transform

The Fourier transform is one of the most fundamental concepts in the information sciences. It's a method for representing an irregular signal such as the voltage fluctuations in the wire that connects an MP3 player to a loudspeaker as a combination of pure frequencies.

The reason the Fourier transform is so prevalent is an algorithm called the fast Fourier transform (FFT), devised in the mid-1960s, which made it practical to calculate Fourier transforms on the fly. Ever since the FFT was proposed, however, people have wondered whether an even faster algorithm could be found.

At the Symposium on Discrete Algorithms (SODA) this week, a group of MIT researchers will present a new algorithm that, in a large range of practically important cases, improves on the fast Fourier transform. Under some circumstances, the improvement can be dramatic a tenfold increase in speed.

Indeed, many of the frequencies may have such low weights that they can be safely disregarded. That's why the Fourier transform is useful for compression. An eight-by-eight block of pixels can be thought of as a 64-sample signal, and thus as the sum of 64 different frequencies. But as the researchers point out in their new paper, empirical studies show that on average, 57 of those frequencies can be discarded with minimal loss of image quality.

Much more; http://web.mit.edu/newsoffice/2012/f...orms-0118.html

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post #632 of 3692 Old 01-25-2012, 12:52 PM
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Originally Posted by coolscan; View Post

The writer of the article doesn't show that he has any more idea of what he is writing about than that he is just repeating some info he has found her and there.

CNET is a respected source, Ty Pendlebury is a respected tech-reporter.
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post #633 of 3692 Old 01-25-2012, 06:00 PM
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Originally Posted by 8mile13 View Post

CNET is a respected source, Ty Pendlebury is a respected tech-reporter.

Oh really? Then why is this article so full of misrepresentations?
http://reviews.cnet.com/8301-33199_7...#ixzz1kT5Bk1Mq
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Still, if you listen to the industry, it'll tell you it's the last resolution you'll ever need.

He opens well. It is a good illustration of the short-sightedness of people "in the industry".

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Despite the industry's best intentions, there is still no single 4K standard-

The two needed standards are in place. One is the DCI standard for movies based in "4x" up-conversion of the DCI 2K standard, and the "4x" up-conversion of the HD/TV home media standard.
SMPTE have just finished or are in the finishing stages for the UHDTV-1 (4K) and UHDTV-2 (8K) broadcast standards.
Basic standards are needed but because of variations of Aspect Ratios nothing will be "pixel accurate".

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-there are five or more different shooting resolutions available.

Capture/shooting resolutions do not need to be standardised as long as they can deliver the minimum within the standards.
Shooting resolutions are camera dependent, and all quality cameras will have much higher resolution than the output resolution they are shooting for.
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In cinemas you see projectors based on the DCI specification, which supports both 4K and 2K, while Sony sports its own standard (also 4,096x2,190-pixel resolution) and series of projectors.

Sony projectors conform to the horizontal part of the 4K DCI cinema standard for 4K. As long as the minimum display resolution is within the standard it doesn't matter if it is higher.
Again; the aspect ratio rules the total amount of pixels displayed.

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Things are a little simpler in the home. The HDMI organization recently added two types of 4K support to its latest 1.4 specification: Quad HD (3,840x2,160 pixels) and 4K/2K, also called 4Kx2K (4,096x2,160 pixels).

So what's his point? The HDMI organization just added to their standard the existing two standards mentioned above.

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Only Quad HD conforms to the classic 16:9 ratio of modern television screens.

4K/2K (4,096x2,160 pixels) has an aspect ratio of 1:89:1, so it has some more "wriggle room" for projection on a screen and aspect ratio variations.
Quad HD (3,840x2,160 pixels) has an aspect ratio of 1:77:1, the most used aspect ratio for broadcast, documentaries and movies. (although most of the most seen movies in the cinema are mostly 2:35-40:1)

The horizontal pixel variations between the two standards are 256 pixels in favour of the 4K cinema standard. On a 8 million pixels display that's nothing much to "quibble about".

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Meanwhile, some industry experts have questioned the necessity of 4K as a home format given the lack of content and the need for very large displays to appreciate the extra resolution.

Because it take longer to develop, manufacture and sell 4K TV's than it takes to produce 4K material or a 4K home format should the 4K display manufacturers wait for the content before they manufacture displays?
One big reason there are not more 4K content is because the content makers don't see the point of 4K material before there are more 4K displays. The lack of 4K displays also slow down the release of 4K home media solutions and hardware releases.

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"There was a huge, noticeable leap from standard definition to HD, but the difference between 1080p and 4K is not as marked," said researcher Dave Lamb of 3M Laboratories.

Is Dave Lamb some sort of authority on 4K?
Compared to a "camera nerd" like Jim Jannard of RED Digital Camera company that has used his own money to build a whole company making 4K and higher resolution digital motion cameras, 4K support software&hardware,4K home delivery format and hardware and projector based solely on " 1080 is not good enough".
Or Sony that have manufactured 4K projectors for years, and now Barco, Christie and NEC are following up.
Or NHK that have been developing 4K Broadcast solutions for many years but now have shifted their focus to 8K broadcast.

All of those who have put "the money where their mouth is" would disagree with David Lamb from 3M. A company AFAIK have no 4K products.
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Lamb added that "4K is at the point of diminishing returns," but there could be some benefits for screens over 55 inches.

I guess that's why we see 20" 4K prototypes from Panasonic. 4K displays on smaller than 55" can also display passive 3D in full HD for each eye compared to the SD resolution of today.
So 4K has many benefits for all screen sizes.

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Did you see James Cameron's "Avatar 3D" in the theater? Then you've seen 4K in action. Cameron's movie about "giant blue dudes" helped drive high-resolution 4K Sony projectors into theaters around the world, and made a lot of money in the process.

"Avatar" was not shot, made or released in 4K, so no one has seen the movie in 4K.
It didn't drive Sony 4K projectors into theatres. The Sony 4K projector can not display 3D in 4K resolution. It can only display 2K for each eye passively.
Only DLP 4K projectors can display 4K 3D with active shutter glasses (also now at higher framerates which the Sony can't).

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Sony announced its 4K home theater projector, the VPL-VW1000ES, in September, but does not make the product available through its Web site or stores and instead sells it directly to custom installers.

The VPL-VW1000ES can be bought through most projector resellers, including AVSciences that own this forum, but at the moment the availabilty might be small.
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Meanwhile, JVC announced four projectors in 2011 that upscale 1080p content to 4K but currently are unable to display native 4K content.

The JVC projector is not a projector with native 4K resolution but make "4K" by some "interpolation".

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Even with reference-quality native 4K material, however, a 4K-resolution TV or projector won't provide nearly the visible improvement over a standard 1080p model that going from standard-def to high-def did.

As he has seen very little good 4K material (or any native 4K material at all) on a good 4K display it is impossible to conclude that the difference will not be as big as from SD to HD. But it will also depend on the type of material, just as it does comparing SD to HD.
When 4K displays are mass produced (not the prototypes we have seen recently) and improved and good 4K native material is available we can start to conclude how large are the benefits.

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To appreciate it you'll have to have sit quite close to a large screen--sort of like being in the front few rows of a movie theater.

That is the same distance to screen "talking point" that is also frequently repeated in this thread.
Won't comment on that now, except to say that "distance to screen" is a very small part of the advantage of the improved quality of 4K imagery.

All in all I find the author of this article as uninformed as most people that write about the "questionable benefit" of 4K and higher resolutions and should not be taken for more than an "popular science" information article about 4K.
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post #634 of 3692 Old 01-25-2012, 08:47 PM
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Quote:
Originally Posted by coolscan; View Post

"

Ty Pendlebury wrote that article not me. If you find the article to be full of misrepresentations then you should mail him and while you're add it you should also mail his boss Katzenmaier, since Pendlebury has no idea what he is talking about i'm shure he will fire him.

If you want to mail Pendlebury yuo must be logged in in the CNET Forum
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post #635 of 3692 Old 01-26-2012, 01:07 AM
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Quote:
Originally Posted by coolscan View Post

There have been some discussions in this thread about how to deliver 4K content without "unmanageable" bit rates.

Recently MIT researchers revealed new faster compression algorithms.

It seems one can not expect wonders from this. Compression is well developed area and it is definitely in the region of removing visually meaningful things for achieving low bit rates

Another problem is that if one has (highly) compressed 4K at a bit rate X then in the TV viewing scenarion 2K compressed at the same bit rate X will be looking not worse and most likely better.

Facing the costly bit rate/bandwidth problem the 4K propaganda machine will be saying: but original 4K compression/transmission is not needed, 2K with upconversion is enough.
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post #636 of 3692 Old 01-26-2012, 02:16 AM
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At a certain point, there is little benefit to higher bitrates. In fact, there are many examples of lower bitrate titles exhibiting less compression artefacts than higher bitrate titles because they used a better tool for encoding the video. (this makes a huge difference)

And keep in mind that when you increase the resolution, you drastically reduce the size any compression artefacts there may be—they don't scale up in size. If the display size stays the same, macroblocking on a 4K display with a 4K source, will be 1/4 the size of 1080p.

At the same file size, higher resolution generally beats lower compression when it comes to image detail.
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post #637 of 3692 Old 01-26-2012, 03:04 AM
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Quote:
Originally Posted by Chronoptimist View Post

At a certain point, there is little benefit to higher bitrates. In fact, there are many examples of lower bitrate titles exhibiting less compression artefacts than higher bitrate titles because they used a better tool for encoding the video. (this makes a huge difference)

And keep in mind that when you increase the resolution, you drastically reduce the size any compression artefacts there may bethey don't scale up in size. If the display size stays the same, macroblocking on a 4K display with a 4K source, will be 1/4 the size of 1080p.

This is true....

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Originally Posted by Chronoptimist View Post

At the same file size, higher resolution generally beats lower compression when it comes to image detail.

..but this is questionable. Simply there will be a region where the 2K is compressed at essentially contribution (transparent) quality while 4K is not.
Say, 2K@100Mb/s is transparent while 4K at this rate is not.
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post #638 of 3692 Old 01-26-2012, 03:35 AM
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Originally Posted by irkuck View Post

..but this is questionable. Simply there will be a region where the 2K is compressed at essentially contribution (transparent) quality while 4K is not.
Say, 2K@100Mb/s is transparent while 4K at this rate is not.

What are you basing this on?

Especially if you are talking about both examples being displayed on a 4K native screen, the 4K source at 100mbps will look considerably better. (let's put aside the fact that you're never going to get a 100mbps 1080p source)

Or do you find that compression artefacts are problematic with 1080p video at 25mbps? (in reality, the 4K source is better off than this, but lets just assume it scales linearly for an easy comparison)
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post #639 of 3692 Old 01-26-2012, 05:31 AM
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Quote:
Originally Posted by Chronoptimist View Post

What are you basing this on?

Especially if you are talking about both examples being displayed on a 4K native screen, the 4K source at 100mbps will look considerably better. (let's put aside the fact that you're never going to get a 100mbps 1080p source)

Or do you find that compression artefacts are problematic with 1080p video at 25mbps? (in reality, the 4K source is better off than this, but lets just assume it scales linearly for an easy comparison)

It is simple: 2K @100 megs is about 10:1 compression, one can even then use simple intraframe compression then. For 4K corresponding bit rate is 400 megs. I am talking about 2K on 2K and 4K on 4K displays.

What I am saying is that, roughly, 25 megs for 2K has 100 megs 4K equivalent. But then if one is talking about 4K @100 megs one should also take 2K @ 100 megs. This is because of logic why to go to 4K @ 100 megs before trying 2K @100 megs? 2K @ 100 megs is transparent studio quality, there will be no need to go to 4K then.

Thus b4 talking about 4K it would much more constructive to talk about increasing the 2K bit rate and frame rate.
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post #640 of 3692 Old 01-26-2012, 06:15 AM
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Originally Posted by irkuck View Post

What I am saying is that, roughly, 25 megs for 2K has 100 megs 4K equivalent. But then if one is talking about 4K @100 megs one should also take 2K @ 100 megs. This is because of logic why to go to 4K @ 100 megs before trying 2K @100 megs? 2K @ 100 megs is transparent studio quality, there will be no need to go to 4K then.

1080p at 100mbps is not "studio quality." If you have a 4K master, as an increasing number of films do, you are throwing away 75% of the resolution. Current Blu-rays are still limited to 8-bit 4:2:0 data in the BT.709 colourspace, increasing the bitrate does nothing to fix that. (and I doubt any stand-alone players could handle 100mbps)

With a good encoder, people would argue that we are approaching visually lossless compression (by that, I mean not having visible compression artefacts) with dual-layer Blu-ray. There will be almost no benefit doubling that to 100mbps. I don't know what you hope to gain from doubling the bitrate limits for 1080p.

Quadrupling the resolution will provide far greater benefits and, especially if better compression is used, will be equivalent to far more than 1080p at 25mbps with the current Blu-ray spec.

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Originally Posted by irkuck View Post

Thus b4 talking about 4K it would much more constructive to talk about increasing the 2K bit rate and frame rate.

Framerate may increase, though it would only apply to new films such as Avatar 2 and The Hobbit, bitrate will not. We are not going to see more than dual layer Blu-rays used for 1080p content.

Furthermore, we aren't even close to filling 50GB Blu-ray discs with film data. I currently have about 150 Blu-rays on my HTPC. The average disc size is less than 30GB. The average film on those discs, without the extras, is under 21GB. Assuming the average length is 90 minutes (I actually suspect the average of the films I have to be closer to 120) That puts the average bitrate at 23mbps 31.4mbps (bad math there)but that includes audio, subtitles, additional commentary tracks or even languages.

So if things scaled linearly you would need 126mbps. But audio isn't going to increase in size, we're already using lossless compression. Skip the useless audio tracks (some films have LPCM, DTS-HD MA and Dolby TrueHD!) and I'm sure you could get that down at or near 100mbps.

Furthermore, I'm not convinced that films do have 4x more resolution there to be exploited. I do believe there's more than 1080p allows for, but complexity is not going to increase 4x, so bitrate demands are not going to scale linearly.

And that assumes you're going to use the same compression scheme. I would expect 4K to improve compression over current Blu-ray, so 100mbps 4K should not suffer any more from compression than Blu-ray currently does, and any compression artefacts that are there, are going to be 1/4 the size of those at 1080p.
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post #641 of 3692 Old 01-26-2012, 01:12 PM
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Increasing 2K BluRay to 100Mbps will not achieve the same thing as running 4K BluRay at that bitrate. Sorry irkuck.

Each "vector" of improvement has a diminishing-returns effect which is why you ultimately need the extra pixels and the information they contain.

There is no difference in HDMI cables. If you can see the picture without visible dropouts or sparklies, the cable is working at 100%. No other cable will display a better version of that picture. You're simply wrong if you think there is a better digital cable than one that is already working. (Oh, and plasma didn't die because of logistics problems, nor does OLED ship in big boxes because it comes from Korea.)
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post #642 of 3692 Old 01-26-2012, 01:12 PM
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Quote:
Originally Posted by Chronoptimist View Post

1080p at 100mbps is not "studio quality." If you have a 4K master, as an increasing number of films do, you are throwing away 75% of the resolution. Current Blu-rays are still limited to 8-bit 4:2:0 data in the BT.709 colourspace, increasing the bitrate does nothing to fix that. (and I doubt any stand-alone players could handle 100mbps)

With a good encoder, people would argue that we are approaching visually lossless compression (by that, I mean not having visible compression artefacts) with dual-layer Blu-ray. There will be almost no benefit doubling that to 100mbps. I don't know what you hope to gain from doubling the bitrate limits for 1080p.

What I am saying is that when having (visually) lossless 2K there is no need of having non-lossless 4K for TV viewing scenario. One can not overcome the human visual system limitations where the benefits of 4K show up at 2.5PH.


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Originally Posted by Chronoptimist View Post

Quadrupling the resolution will provide far greater benefits and, especially if better compression is used, will be equivalent to far more than 1080p at 25mbps with the current Blu-ray spec.

Framerate may increase, though it would only apply to new films such as Avatar 2 and The Hobbit, bitrate will not. We are not going to see more than dual layer Blu-rays used for 1080p content.

Furthermore, we aren't even close to filling 50GB Blu-ray discs with film data. I currently have about 150 Blu-rays on my HTPC. The average disc size is less than 30GB. The average film on those discs, without the extras, is under 21GB. Assuming the average length is 90 minutes (I actually suspect the average of the films I have to be closer to 120) That puts the average bitrate at 23mbps 31.4mbps (bad math there)but that includes audio, subtitles, additional commentary tracks or even languages.

So if things scaled linearly you would need 126mbps. But audio isn't going to increase in size, we're already using lossless compression. Skip the useless audio tracks (some films have LPCM, DTS-HD MA and Dolby TrueHD!) and I'm sure you could get that down at or near 100mbps.

Furthermore, I'm not convinced that films do have 4x more resolution there to be exploited. I do believe there's more than 1080p allows for, but complexity is not going to increase 4x, so bitrate demands are not going to scale linearly.

And that assumes you're going to use the same compression scheme. I would expect 4K to improve compression over current Blu-ray, so 100mbps 4K should not suffer any more from compression than Blu-ray currently does, and any compression artefacts that are there, are going to be 1/4 the size of those at 1080p.

Here you undermine the case for 4K even further: if there is no real 4K source then why go to 4K. I see it differently: one can produce real 4K at least in animated movies but benefits of it comparing to the (visually) lossless 2K will be nil due to the vision limitations. From your arguments it follows that any increase in resolution is beneficial, why not 8K then. From my argument it follows that increase in resolution is irrelevant. Before talking about it would be logical to talk about producting real 2K content (movies are not 1920 but 1440), visually lossless and increase the frame rate. That would fill absolute limits of visual perception for video.
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post #643 of 3692 Old 01-26-2012, 01:25 PM
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Quote:
Originally Posted by irkuck View Post

Here you undermine the case for 4K even further: if there is no real 4K source then why go to 4K.

There is more than 1080p information in the film source. I don't believe that most films would benefit much from going beyond 4K right now. Films shot on digital cameras with modern lenses, or films shot on large formats, well that's another matter.

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Originally Posted by irkuck View Post

I see it differently: one can produce real 4K at least in animated movies but benefits of it comparing to the (visually) lossless 2K will be nil due to the vision limitations.

1080p is not "visually lossless" at all.

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Originally Posted by irkuck View Post

From your arguments it follows that any increase in resolution is beneficial, why not 8K then.

I will be lining up to buy an 8K display as soon as they're available & affordable. Until we have new content though, there will be little benefit to having an 8K display purely for video purposes.

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Originally Posted by irkuck View Post

Before talking about it would be logical to talk about producting real 2K content (movies are not 1920 but 1440), visually lossless and increase the frame rate. That would fill absolute limits of visual perception for video.

Every single Blu-ray I have is 1920x1080.

1440x1080 is broadcast 1080i on some stations (some are 1920x1080) and cheap consumer-grade camcorders.
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post #644 of 3692 Old 01-26-2012, 03:49 PM
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More info on the new H.265 standard promising a 40% reduction in needed bitrate. Let's start streaming those 4K studio masters.

http://www.vcodex.com/h265.html
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Even if that's 40% with absolutely no negative effects, we will need quad-layer BluRay to enjoy 4K properly. Currently, movies routinely use mid-30s megabits/second (not all of them) which puts a 2-hour film north of 30GB. Even if you could get 40% more efficient, since you are dealing with 4x as much data, you'd have math like 4 x (34 x .6) = 80+ GB.

If you tried to cram this onto a 50GB disc, the benefits of 4K will be lost.

There is no difference in HDMI cables. If you can see the picture without visible dropouts or sparklies, the cable is working at 100%. No other cable will display a better version of that picture. You're simply wrong if you think there is a better digital cable than one that is already working. (Oh, and plasma didn't die because of logistics problems, nor does OLED ship in big boxes because it comes from Korea.)
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post #646 of 3692 Old 01-26-2012, 11:38 PM
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Originally Posted by Chronoptimist View Post

I will be lining up to buy an 8K display as soon as they're available & affordable. Until we have new content though, there will be little benefit to having an 8K display purely for video purposes.

There is thus no base for further discussion: your position of "the more pixels the better" is defying elementary logic, laws of physics, and knowledge of human vision. This belief in the improvement of PQ by multiplying pixels 2K, 4K, 8K,... is digital equivalent of creationism belief .

Anyone who believes in pixel miracles should read hard-core information.
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post #647 of 3692 Old 01-26-2012, 11:42 PM
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Originally Posted by sytech View Post

More info on the new H.265 standard promising a 40% reduction in needed bitrate. Let's start streaming those 4K studio masters.
http://www.vcodex.com/h265.html

To see problems here answer this question: Why Blu-rays are not compressed to the same bit rate as in the HDTV broadcast? (We assume you know what are the rates used).
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post #648 of 3692 Old 01-27-2012, 07:36 AM
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Originally Posted by rogo View Post

Even if that's 40% with absolutely no negative effects, we will need quad-layer BluRay to enjoy 4K properly. Currently, movies routinely use mid-30s megabits/second (not all of them) which puts a 2-hour film north of 30GB. Even if you could get 40% more efficient, since you are dealing with 4x as much data, you'd have math like 4 x (34 x .6) = 80+ GB.

If you tried to cram this onto a 50GB disc, the benefits of 4K will be lost.

With my previous post, I was going off estimates based on what my collection seemed to be. Filesize was correct, but I used an average of 90 minutes, which was completely wrong as it turned out. I've now spent far too much time (much longer than I expected) cataloguing the majority of my collection, which is 138 titles. (some of it is still on discs that have not yet been stored away, and they have not been included)

Previously with my HTPC, I was ripping just the film off the disc with the primary audio track, subtitles and nothing else. (no extras, menus etc) Now, I just rip the entire disc, as that's quicker & easier. (even though it's far less efficient on space)

Of the ripped titles, which are the film with one audio and subtitle track, the average size is 20.35GB. As I had expected, the average length is far more than 90 minutesit's 01:56:34. That works out as being around 24.26mbps average, though that includes the audio data as well.

Including everything, the majority of which are full discs with multiple audio tracks, subtitles etc, the average filesize is 24.83GB. The average length is 01:59:53, and so the average bitrate there is 28.44mbps. Again, that is including multiple audio tracks, and several of the discs I have, have multiple HD tracks on them. (either offering an English dub, or simply different formats such as LPCM and Dolby TrueHD/DTS HD MA)


So if you are looking at a 4x increase in resolution, and a 40% increase in compression efficiency, that works out to be 59.59GB for 4K at the same quality as Blu-raynot too far off a dual-layer disccertainly not requiring quad-layer.

While resolution will be going up 4x, detail/complexity will not. Audio quality is not going to change, and if you look at the numbers posted above, as much as 4.5GB is unnecessary audio, which would bring that number down to 48.84GB. It will not require 4x the filesize to go to 4K with the same compression quality of current discs.

I'm sure it would be much easier & cheaper to use a dual-layer disc for the film itself, and include a single layer disc for any extras. And as I keep saying, any compression artefacts that do appear at 4K will be 1/4 the size of those at 1080p, so you could probably get away with slightly worse compression (not that I think that will actually be the case) while still ending up with a better image on the display.

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To see problems here answer this question: Why Blu-rays are not compressed to the same bit rate as in the HDTV broadcast? (We assume you know what are the rates used).

Blu-rays are compressed using MPEG2, VC-1 or H.264
H.265 is a more advanced compression algorithm that does not require bitrates as high as any of these, for the same quality image.

Bitrates really don't matter. It's the quality of the codec, and the encoder used that matters the most when it comes to image quality.

In fact, almost universally, the highest bitrate titles, are far from being the best looking discs. Many times, they are some of the worst looking discs I own. The reason that the bitrates are so high, is because whoever did the mastering added a lot of edge enhancement, used a poor encoder, and simply cranked up the bitrate as an attempt to compensate. They also tended to be shorter in length, closer to 90 minutes rather than the average of 120.

Of the discs which had high bitrates, but actually looked good, they were films which had a dual-layer disc, and barely any extras, so it's clear that they simply wanted to fill the disc, rather than it actually being necessary.

Some of the best discswhich many consider to be reference quality titlesare in the 20-25mbps range, and often the lower end of it. Virtually all of the discs which actually look really good, are compressed using H.264 at 30mbps or less. (and really, it's even lower than that if you were to take out the extra audio tracks)

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There is thus no base for further discussion: your position of "the more pixels the better" is defying elementary logic, laws of physics, and knowledge of human vision. This belief in the improvement of PQ by multiplying pixels 2K, 4K, 8K,... is digital equivalent of creationism belief .

Anyone who believes in pixel miracles should read hard-core information.

You assume that everyone owns small televisions and sits very far from their displays. I don't.

The kind of person to buy a 4K display, is the kind of person likely to buy larger screens, and wants a home theatre experience, sitting up close, rather than a television experience, looking at a postage-stamp sized image across a room.

As I've said many times in here, 4K is not going to be replacing 1080p any time soon. It will be a level above 1080p displays, and there's far more use to a 4K display than simply watching films.

If you are satisfied by 1080p, so be it. Many of us are not.
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Even if that's 40% with absolutely no negative effects, we will need quad-layer BluRay to enjoy 4K properly. Currently, movies routinely use mid-30s megabits/second (not all of them) which puts a 2-hour film north of 30GB. Even if you could get 40% more efficient, since you are dealing with 4x as much data, you'd have math like 4 x (34 x .6) = 80+ GB.

If you tried to cram this onto a 50GB disc, the benefits of 4K will be lost.

Not only that, but if the industry starts to move to 48fps, that instantly doubles the space required.
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Not only that, but if the industry starts to move to 48fps, that instantly doubles the space required.

Did moving to stereoscopic 3D double the space required? It would double the space required if you were storing uncompressed video, but not with compressed.
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There is thus no base for further discussion: your position of "the more pixels the better" is defying elementary logic, laws of physics, and knowledge of human vision. This belief in the improvement of PQ by multiplying pixels 2K, 4K, 8K,... is digital equivalent of creationism belief .

Anyone who believes in pixel miracles should read hard-core information.

There is lot of nonsense on the web, your reference notwithstanding. I vaguely remember one professor referring to 4000x4000 pixels black and white CRT monitor back in the 80s. His quote: "This is as much resolution as human eye can possibly digest". Indeed, knowing that human eye resolve 1 arc minute we have 60x60=3600 linear pixels for 60 degree point of view.
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Chron wrote:

"So if you are looking at a 4x increase in resolution, and a 40% increase in compression efficiency, that works out to be 59.59GB for 4K at the same quality as Blu-ray—not too far off a dual-layer disc—certainly not requiring quad-layer."

So in your world, you've now stripped off all the extras and the average movie doesn't fit on a BluRay. By the way, no BluRay player supports 4K anyway.

Since even by your math we need 3-layer to do movies with no extras -- something the industry won't support -- we need quad layer, which I've stated from the beginning and you've proved.

I'm not sure why you don't get that, but that's what we need -- a 100GB disc format.

By the way, I'm not worried about making quad-layer BluRay work for 4K. It's just the format we're going to need.

There is no difference in HDMI cables. If you can see the picture without visible dropouts or sparklies, the cable is working at 100%. No other cable will display a better version of that picture. You're simply wrong if you think there is a better digital cable than one that is already working. (Oh, and plasma didn't die because of logistics problems, nor does OLED ship in big boxes because it comes from Korea.)
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IMHO I think we need to settle somewhere in the middle and be pragmatic.

1) bit rate is not everything, though like resolution, it is an easy heuristic conclusion. If higher bit rate means better picture then less efficient compression will be "bettter". To complicate matters, even with same codec, my home video will not look better than Hollywood even if it has high bitrate.

2) that said, higher resolution does mean higher bit rate and storage space, that is a given. But it doesn't mean 4X resolution or info means 4X bitrate or storage. That's not how lossy compression works. Thats another heuristic conclusion. Lossless OTOH is different.

3) you should find out why string theory was developed and what is the implication of space-time singularity or schrodinger's cat, before you ironically arrive at a convenient heuristic conclusion that you trying to dispel.

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is digital equivalent of creationism belief

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"So if you are looking at a 4x increase in resolution, and a 40% increase in compression efficiency, that works out to be 59.59GB for 4K at the same quality as Blu-raynot too far off a dual-layer disccertainly not requiring quad-layer."

So in your world, you've now stripped off all the extras and the average movie doesn't fit on a BluRay. By the way, no BluRay player supports 4K anyway.

Well that number was for films where I hadn't stripped them down. Stripped down, it worked out to be 48.84GB, and in reality it would be even less than that, as that number still includes the audio track (audio size will not change going from 1080p to 4K) and image complexity is not going to scale up 4x, even though resolution is, which means that you won't actually need 4x the size for the same image quality.

Make it so that the new spec for 4K requires the player to decode losslessly compressed audio (perhaps move to multichannel FLAC, which is license free and more efficient) rather than wasting space with LPCM, and have it properly downmix surround sound rather than include separate stereo tracks, and the only time additional audio tracks are required would be for multiple languages or commentaries, rather than having several different versions of an English audio track wasting space on the disc for the sake of redundancy.

I'm not saying it's going to happen, just that it would certainly be possible to put 4K on a dual-layer Blu-ray disc without any real compromises, as long as you don't waste space on the disc with extras and trailers, putting them on a separate disc if necessary. (right now I would expect a package with a dual-layer and single-layer disc to be cheaper to produce than a quad-layer disc) Personally I don't consider that to be a compromise as I never watch/listen to any of that stuffit used to be interesting when it was a new thing with DVD back before it was manufactured alongside the film as part of the process, now I couldn't care less, and I'd rather spend the time watching another film instead.


With a quad-layer disc, 4K becomes easy. My main point is that storage space is not going to be a problem for 4K films, and it could be done without a new disc format. (but will require new players)


The biggest problem with 4K would be marketing. Not trying to convince people that there is a benefit to it (I'm sure that people will be able to see that for themselves) but if we have 4K home releases, that means putting out another disc, as the 4K Blu-ray isn't going to work on a 1080p Blu-ray player, and they'll probably still want to have DVD releases. Frankly, I'm surprised that we haven't yet reached the point where it's cost prohibitive to manufacture DVDs in addition to a Blu-ray release. The format is 16 years old, and should be dead at this point. Studios just need to put an end to it, and stop putting out new releases on DVD.
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DVD outsells BluRay. The studios like money.

I expect the 4K discs will be readable in older players which can only see the 2 layers and have a BluRay on them as well.

There is no difference in HDMI cables. If you can see the picture without visible dropouts or sparklies, the cable is working at 100%. No other cable will display a better version of that picture. You're simply wrong if you think there is a better digital cable than one that is already working. (Oh, and plasma didn't die because of logistics problems, nor does OLED ship in big boxes because it comes from Korea.)
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Did moving to stereoscopic 3D double the space required? It would double the space required if you were storing uncompressed video, but not with compressed.

I believe you're wrong there. Why would it matter if it was compressed or not? For a 2hr movie at 24fps, you're looking at 172,800 frames, each of those frames has a certain amount of 1s and 0s associated with it. Double the frame rate, double the amount of frames, double to amount of data, double the amount of space required. Now, if you can provide a reason why I am wrong, I'll be happy to be proven wrong as that means moving to 48fps would be even less of an issue of studios.

I'm not sure about 3D as I'm not a fan of it, but if it doesn't require more space, it might have something to do with the fact that it's basically displaying the same frame in different ways so it doesn't need any more data.
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DVD outsells BluRay. The studios like money.

Surely that's only because it's there as a cheaper alternative though? It's not like Blu-ray players are costing hundreds any more.

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I expect the 4K discs will be readable in older players which can only see the 2 layers and have a BluRay on them as well.

Makes sense.
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Surely that's only because it's there as a cheaper alternative though? It's not like Blu-ray players are costing hundreds any more.

No, it's installed base + inertia + places where BluRay ain't.

People have portable DVD for their kids, DVD players in their homes they see no need to replace, a lack of interest in change for change sake, confusion that the new BluRay player will handle their DVDs, etc.

It's not about cost, it's that technology transformations take time -- especially when the new good is not very different from the old one. Most people don't consider the BluRay upgrade very important. It happens when it happens, not through an affirmative step -- for most people.

For this reason, I expect 4K adoption to be glacially slow as far as media goes. It's questionable whether it can sustain a market (think DVD-Audio / SACD). I hope it does, but it's definitely questionable.

There is no difference in HDMI cables. If you can see the picture without visible dropouts or sparklies, the cable is working at 100%. No other cable will display a better version of that picture. You're simply wrong if you think there is a better digital cable than one that is already working. (Oh, and plasma didn't die because of logistics problems, nor does OLED ship in big boxes because it comes from Korea.)
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Quote:
Originally Posted by Joe Bloggs View Post

Did moving to stereoscopic 3D double the space required? It would double the space required if you were storing uncompressed video, but not with compressed.

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Originally Posted by Ryan711 View Post

I believe you're wrong there. Why would it matter if it was compressed or not?

Because with uncompressed video, more frames would mean more bitrate needed. If you had twice as many frames in the video it would take about twice as much space (might not be exactly twice as much as you might only need things like the video header stored once, and it wouldn't alter the space needed for audio).
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For a 2hr movie at 24fps, you're looking at 172,800 frames, each of those frames has a certain amount of 1s and 0s associated with it. Double the frame rate, double the amount of frames, double to amount of data, double the amount of space required. Now, if you can provide a reason why I am wrong, I'll be happy to be proven wrong as that means moving to 48fps would be even less of an issue of studios.

The reason is, with compressed video, the person doing the encoding can select the bitrate (or target, max bitrate etc.) that is used for the video (it actually can depend on the codec but they can for things like H264/AVC as used by Blu-ray). Now it's true that if they told it to encode at a bitrate that was too low for a particular video it may lead to visible artefacts, but with higher fps video, all other things being equal, the amount of movement between each frame would be less, so should be easier to compress (ie. wouldn't need twice the bitrate to achieve the same quality). Also, even if there were more artefacts in the compressed video at 48 fps vs 24 fps, each frame would be displayed for half the time at 48 fps, so any problems with any frames should be less noticable (as it would go by faster) - unless the next frame had the same artefacts at the same locations.

Here are some examples:

Uncompressed
* 10 seconds of 1280x720p video (no audio) at 30 fps, 8 bit RGB colour takes about 791 MB
* 10 seconds of 1280x720p video (no audio) at 60 fps, 8 bit RGB colour takes about 1.54 GB
So this shows that for uncompressed video, doubling the frame rate does double the amount of space required (all other things being equal, and except things like the header will only be once in the file, but things like that are only a small amount of the file, and this is only talking about the video - the size occupied by the audio wouldn't increase).

Compressed
Video can be compressed at about whatever target compression bitrate the person compressing the video decides (depending on the codec and allowed bitrate ranges).

Telling it to compress at 25.1183 Mbps, Constant Bitrate (though Variable Bitrate should give the best picture quality for a particular file size):
* 10 seconds of 1280x720p video (no audio) at 23.976 fps using H.264 (as used by Blu-ray) gave a file size of 29.6 MB (in theory it should have been about 31.4 MB if it actually compressed it at exactly the rate told)
* 10 seconds of 1280x720p video (no audio) at 59.94 fps using H.264 (as used by Blu-ray) gave a file size of 29.6 MB (in theory it should have been about 31.4 MB if it actually compressed it at exactly the rate told)

So as we see above, for the above compressed files, both of which are the same duration, the 720p file at 59.94 fps has exactly the same file size as the one with the same resolution at 23.976 fps, even though the frame rate has more than doubled.
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I'm not sure about 3D as I'm not a fan of it, but if it doesn't require more space

They say 3D using the codec they're currently using (MVC) needs around 50% more bitrate (though it would depend on picture content too) to achieve the same picture quality as the 2D version (though again, they can choose the bitrate - they could choose to use the same bitrate as the 2D version - but picture quality may be visibly reduced).
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The kind of person to buy a 4K display, is the kind of person likely to buy larger screens, and wants a home theatre experience, sitting up close, rather than a television experience, looking at a postage-stamp sized image across a room.

As I've said many times in here, 4K is not going to be replacing 1080p any time soon. It will be a level above 1080p displays, and there's far more use to a 4K display than simply watching films.

If you are satisfied by 1080p, so be it. Many of us are not.


Ah, now we arrived at full agreement. If 4K is intended for people wanting to watch in scenario like cinema front rows then 4K is absolute necessity. Since almost all people don't buy TVs for this kind of watching then either 4K will be a fad or a niche. Notice also that manufs do not advertise this viewing scenario since people would reject 4K immediately.


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There is lot of nonsense on the web, your reference notwithstanding. I vaguely remember one professor referring to 4000x4000 pixels black and white CRT monitor back in the 80s. His quote: "This is as much resolution as human eye can possibly digest". Indeed, knowing that human eye resolve 1 arc minute we have 60x60=3600 linear pixels for 60 degree point of view.

Full agreement here! TV scenario assumes 30 deg and this is why there is 1920 (not 1800/2000 since 1920 was nicer as being multiple of VGA 640). The point is that 60 deg viewing means viewing distance about 2PH which is not how people are viewing in their sitting rooms.

What is being endlessly repeated here is that resolution required depends on the viewing scenario. For the computer monitor scenario 4K is really a necessity, for standard TV 2K is enough, but for immersive TV and games the 4K is also necessary. The point is the 4K scenario is not how people watch their TVs.
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