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post #1 of 26 Old 09-04-2013, 12:51 PM - Thread Starter
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http://www.hdmi.org/press/press_release.aspx?prid=133

4K @ 60hz.

Uses same connectors as current HDMI 1.4.

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post #2 of 26 Old 09-05-2013, 04:02 PM
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Too bad they are just as sloppy as everybody else about differentiation of UHD and 4K when they are NOT the same thing! These people are supposed to be "the pros" and are supposed to understand all these finer points with great clarity.

4K is 4096 horizontal pixels with variable vertical pixels depending on aspect ratio. UHD is 2160 vertical pixels with 3840 horizontal pixels, or 4-times HD resolution, though some horizontal lines of pixels will always be black if the aspect ratio is larger than 1.78:1.

Doesn't give much hope that implementation of HDMI 2.0 will be any better than previous versions with all the compatibility issues.

I also question their statement that 2160p has 4 times the clarity of HD video... 4 times the pixels, yes. 4 times the clarity? I don't think so and I have no idea how you would ever quantify such a statement anyway. Not many would argue that HD is "clearer" than SD, but the number of pixels is about 5.9 times greater for HD vs SD. Would anybody ever say HD has 5.9 times more clarity than SD? I don't think so since there are no measures of "clarity". Resolution does not equal clarity, there are many other variables.

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post #3 of 26 Old 09-05-2013, 07:54 PM
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There is too much put into resolution. Going from 1080p to 2160p might not be very noticeable. We will see in 12-18 months when we have quality 4k sources to judge a good 1080p transfer to a 2160p transfer. I'm curious, after having 3 jvc eshift projectors and seeing the Sony 1000ES, I don't see upscaled 2k to 4k being a reason to jump into 4k until you can go to Best Buy and pick up a 4K blu ray
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post #4 of 26 Old 09-05-2013, 07:57 PM
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Also, is the color bit still at 8 bits? I thought the higher bits of color was going to make more of a difference between 2k and 4k than resolution. So, it too so long to do 60hz in 4k. Well, I guess 3D is in 4k.
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post #5 of 26 Old 09-06-2013, 12:28 AM
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?
Since HDMI 1.3 you can have up to 16 bits.
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post #6 of 26 Old 09-06-2013, 12:52 AM
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Originally Posted by AV-Freak View Post

?
Since HDMI 1.3 you can have up to 16 bits.

So, why do blu ray only use 8 bits?
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post #7 of 26 Old 09-06-2013, 01:20 AM
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Because the Blu-ray Disc Association defined it so.
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post #8 of 26 Old 09-06-2013, 01:20 AM
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Quote:
Originally Posted by AV-Freak View Post

?
Since HDMI 1.3 you can have up to 16 bits.

blee0120, is talking about movie color depth which is 8bit for Blu-Ray (4:2:0).

I believe the next improvement will be the transition from Blu-Ray's Chroma Subsampling 4:2:0 to 4:4:4. This change will need a lot of more space but the difference will be more noticed.







4:4:4 Original still image.


4:2:0 progressive sampling applied to a still image.


4:4:4 Moving Text Still Image. The moving text has some motion blur applied to it.


4:2:0 progressive sampling Moving Text Still Image. *Note that the chroma leads and trails the moving text.

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post #9 of 26 Old 09-06-2013, 01:43 AM
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Maybe, but that are restrictions of the BluRay standard and not HDMI level.
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post #10 of 26 Old 09-06-2013, 01:53 AM
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Originally Posted by AV-Freak View Post

Maybe, but that are restrictions of the BluRay standard and not HDMI level.

Exactly

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post #11 of 26 Old 09-06-2013, 02:38 AM
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Quote:
Originally Posted by ConnecTEDDD View Post

blee0120, is talking about movie color depth which is 8bit for Blu-Ray (4:2:0).

I believe the next improvement will be the transition from Blu-Ray's Chroma Subsampling 4:2:0 to 4:4:4. This change will need a lot of more space but the difference will be more noticed.







4:4:4 Original still image.


4:2:0 progressive sampling applied to a still image.


4:4:4 Moving Text Still Image. The moving text has some motion blur applied to it.


4:2:0 progressive sampling Moving Text Still Image. *Note that the chroma leads and trails the moving text.

thats really noticeable
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post #12 of 26 Old 09-06-2013, 10:28 AM
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Originally Posted by Doug Blackburn View Post


I also question their statement that 2160p has 4 times the clarity of HD video... 4 times the pixels, yes. 4 times the clarity? I don't think so and I have no idea how you would ever quantify such a statement anyway. Not many would argue that HD is "clearer" than SD, but the number of pixels is about 5.9 times greater for HD vs SD. Would anybody ever say HD has 5.9 times more clarity than SD? I don't think so since there are no measures of "clarity". Resolution does not equal clarity, there are many other variables.

what if they used the term sharpness instead?

from (http://www.avsforum.com/t/852536/basic-guide-to-color-calibration-using-a-cms-updated-and-enhanced)

Sharpness is the quality of an image that gives it clearly defined boundaries. This should not be confused with the type of artificial sharpening that you often see in poor DVD transfers an excessive use of the sharpness control on the display. These only result in ringing and edge enhancement, which makes the image worse instead of better. A good example of sharpness can be had by comparing a good plasma or LCD display with a good CRT. CRTs can look very nice, but they simply cannot complete with the sharpness of a plasma or LCD.

Clarity is the quality of an image that appears when the image is free of artifacts. These artifacts come in a wide variety of types and for a wide variety of reasons. They include: poor focus, poor geometry, poor convergence, chromatic aberration, ringing, moire, line twitter, and interference/ghosting/snow (for over-the-air broadcast).
Problems with image clarity are result of the quality of the optics, processing, or mechanical alignment, and involve the display adding something to the image that is not originally there. Problems with sharpness can be influenced by the resolution, optics, and other inherent properties of the display device, and involve the display removing from the image something that was originally there.

The importance of these two factors is perhaps best illustrated by thinking back to the first time you saw a good plasma display fed by a good source. Compared to CRT images, plasmas could produce an image with startling clarity and sharpness that results in an almost scary looking-though-a-window quality that CRTs simply cannot match. The important fact to note for this discussion is that these relatively early plasma displays offered lower resolution, much lower contrast, and often worse color accuracy than the CRTs of the day and they still could look better, sometimes much better.
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post #13 of 26 Old 09-06-2013, 03:51 PM
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Blu-ray has 8-bit color because when the format was released, there were only single-layer 25GB discs. When you reserve some space for special features, reserve some space for a DTS HD MA or TrueHD soundtrack (and maybe a few other languages in DD), there's only enough space left on a single-layer Blu-ray disc for a 2.5 hour movie if the video is in decimated (i.e. 4:2:0) 8-bit video. The committee probably knew that adding a second layer was inevitable, but at the time the standard was set, there were only single-layer discs. For a 4K disc format, there's really nowhere to go to make the pit size smaller on the discs... the blue laser has the smallest diameter laser unless something like an ultraviolet laser is developed. So optical disc layers are going to be stuck pretty close to 25 GB for a while. With 4-times more pixels for UHD (home video is not 4K and it appears it will never be 4K, so it shouldn't be called 4K, 4K is a digital cinema format though), you'd need either 100 GB for a single sided disc (with no extras, probably) or you'd need 4 layers for the movie and additional layers for other features. Disc manufacturing now allows more than 4 layers so a new disc format would have to be adopted in order for us to have a movie format with more than 8-bit color. Call it Ultra-Blu-Ray (to go with Ultra HD) for the time being. Not only could it support more bits per color, but it could also make use of a much larger color space than the Rec. 709 space used for HDTV and Blu-ray.

More bits per color will FINALLY allow us to have video without contouring. Well... hypothetically anyway. 8-bit color using 16-235 has 219 levels. Human vision has been measured as being able to see 200 shades of gray plus or minus a few depending on which study you look at. So hypothetically, 8-bits should be enough to avoid contouring. But that doesn't seem translate to real-world HD video, at least not very often. It may be possible to master a disc in 8-bit space without visible contouring, but each component that touches the video from the disc player to AVR/processor, to video display likely does SOMETHING to the video even in bypass mode and if that isn't controlled perfectly (and typically video processing is done in 10 bit space with some exceptions at 12 bits and Samsung at 18-bits internally... but those processing steps have to be down-converted back to 8-bits and that's another point where it has to be done perfectly or you end up with contouring again. So 10-bit color SHOULD be enough to avoid visible contouring entirely, but with all the vagarities of video processing, I think it's possible that people could still screw-up 10-bit video so it's likely that it will take 12-bit video to really make all contouring issues a thing of the past. But the leap from 8-bits to 12-bits takes a LOT more storage space on the disc also... so now you want UHD on disc PLUS you want it in 12-bits so now you're up against the limits of what can be manufactured with current technology. I think I read something that indicated 8 layers was about the limit foreseen for economical production of discs and players. That just might be enough to accommodate HD at 12-bits but may not be much room for extras (additional languages, special features, etc.).

So we're on the threshold of moving on to a completely new video standard... HDMI 2.0 is just the first piece of the puzzle. We also need a new standard for the UHD format, presumably with more bits and a larger color space. Then we need a disc format that will support the new standard, and probably be backward compatible. After we get the new disc format, we then need new disc players and discs that support the new format. There are many steps to getting to the next video standard and things are just getting started that will let us get to this new standard.

Someone mentioned that 3D was already a 4K format... no it is not. 3D is achieved by sending a "regular" HD frame plus about 20%-25% more data that describes the differences seen by the "other" eye so that second frame can be "built" with very little additional data. 3D is an HDTV format with 1920x1080 resolution. But we are seeing 48 frames per second from a 24 frame per second Blu-ray disc. The right eye image is displayed for 1/48 of a second, and the left eye image is displayed for 1/48 of a second so you get the same 24 fps/Hz you get from a 2D Blu-ray movie. UHD 3D will require some sort of specification for 3D as well as 2D... that could be something similar to the HDTV frame-packed 3D format or it could be achieved some different way.

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post #14 of 26 Old 09-06-2013, 04:11 PM
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Quote:
Originally Posted by Doug Blackburn View Post

8-bit color using 16-235 has 219 levels.

You forgot to count the '16' as a level, it's 220 in total, for 16-235 Video Range. 220×220×220 or 10.648.000 possible colors (8bit).

BTW Full Range 0-255 has 256 levels in total.

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post #15 of 26 Old 09-07-2013, 05:52 AM
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Doug: Is the HDMI 2.0 pipeline size of ~ 18 Gbit large enough to accommodate both 12 bit color and UHD? Thanks
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post #16 of 26 Old 09-07-2013, 03:52 PM
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Is 18 Gbps enough for 12-bit color...

Simple math problem

36 bits per (white) pixel. 3820x2160 pixels per frame times (up to) 60 frames per second

3820x2160 = 8251200

36 x 8251200 x 60 = 17,822,592,000 bits per second, almost 18 Gbps

So, yes, it would appear 12-bit would be supported, but JUST BARELY. No room for audio, not much room for "overhead" or "housekeeping". If that's just the limit for VIDEO, no problem, additional bandwidth would be available for audio and, presumably 4K 3D would be supported somehow also, but it would need something like an additional 3.6 Gbps or so for the extra overhead for the "second eye" frame.

Of course, that assumes uncompressed video, like RGB or YCbCr 4:4:4. Just changing to 4:2:2 is a big savings in bandwidth, but not sure that's enough savings to include lossless audio within the entire 18 Gbps budget. Need more specifics.

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post #17 of 26 Old 09-07-2013, 04:00 PM
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Quote:
Originally Posted by Doug Blackburn View Post

Is 18 Gbps enough for 12-bit color...

Simple math problem

36 bits per (white) pixel. 3820x2160 pixels per frame times (up to) 60 frames per second

3820x2160 = 8251200

36 x 8251200 x 60 = 17,822,592,000 bits per second, almost 18 Gbps

So, yes, it would appear 12-bit would be supported, but JUST BARELY. No room for audio, not much room for "overhead" or "housekeeping". If that's just the limit for VIDEO, no problem, additional bandwidth would be available for audio and, presumably 4K 3D would be supported somehow also, but it would need something like an additional 3.6 Gbps or so for the extra overhead for the "second eye" frame.

Of course, that assumes uncompressed video, like RGB or YCbCr 4:4:4. Just changing to 4:2:2 is a big savings in bandwidth, but not sure that's enough savings to include lossless audio within the entire 18 Gbps budget. Need more specifics.


17.822.592.000 bits per second for uncompressed 4:4:4 12bit
13.366.944.000 bits per second for compressed 4:2:2 12bit
8.911.296.000 bits per second for compressed 4:2:0 12bit

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post #18 of 26 Old 09-07-2013, 09:36 PM
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Quote:
Originally Posted by ConnecTEDDD View Post

17.822.592.000 bits per second for uncompressed 4:4:4 12bit
13.366.944.000 bits per second for compressed 4:2:2 12bit
8.911.296.000 bits per second for compressed 4:2:0 12bit
HDMI 2.0 has a bit rate of 18 Gbps but after taking out the overhead for TMDS that leaves a bit rate of 14.4 Gbps. I did the calculations for 3840 x 2160 x 60 x (bits per pixel) and what I got was:

17.9 Gbps for 12-bit 4:4:4
11.9 Gbps for 12-bit 4:2:2
8.9 Gbps for 12-bit 4:2:0

12-bit 4:2:2 should be possible with HDMI 2.0. It would be nice if that was confirmed though and I am also curious to know if HDMI 2.0 will support the Rec. 2020 color space.
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post #19 of 26 Old 09-08-2013, 01:34 PM
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I am also curious to know if HDMI 2.0 will support the Rec. 2020 color space.

Yes it will. I asked an engineer this question after press conference on IFA 2013. Although, he couldn't tell me if the mechanism will be resolution-independent.
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post #20 of 26 Old 09-08-2013, 02:31 PM
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is all this talk about *the implementation* of stuff like 4:4:4 and 12-bit color confirmed by hdmi.org/major consumer electronics manufacturers or is it merely speculation at this point based on supported features of the current HDMI spec?
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post #21 of 26 Old 09-08-2013, 04:12 PM
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Is more info on hdmi 2.0 coming out later? I thought we would have all info now
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post #22 of 26 Old 09-09-2013, 02:24 AM
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Quote:
Originally Posted by PlasmaPZ80U View Post

is all this talk about stuff like 4:4:4 and 12-bit color based on hard evidence or is it merely an educated guess/speculation?
What exactly do you mean with your question?
All this features are supported since 1.3 - so this is old "evidence".
But supported does not mean that anybody will be using them.
With HDMI 2.0 only 480p with 2 audio channels is obligatory the rest is complimentary (now they even establish 4:2:0 as supported format).
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post #23 of 26 Old 09-09-2013, 10:34 AM
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What exactly do you mean with your question?
All this features are supported since 1.3 - so this is old "evidence".
But supported does not mean that anybody will be using them.
With HDMI 2.0 only 480p with 2 audio channels is obligatory the rest is complimentary (now they even establish 4:2:0 as supported format).

that's what I meant to say... is there any clear indication that things like 12-bit color and YCbCr 4:4:4 will be used anytime soon (in the next few years or so)?
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post #24 of 26 Old 09-09-2013, 01:43 PM - Thread Starter
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that's what I meant to say... is there any clear indication that things like 12-bit color and YCbCr 4:4:4 will be used anytime soon (in the next few years or so)?

I don't believe so.

Compression is king in transmitting data and large optical storage seems to be going away. There may be products like Red's redray that are native 12bit 4:2:2, but we'll see if anything gets enough consumer adoption to make a non-trivial amount of content available with that kind of definition.

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post #25 of 26 Old 09-09-2013, 03:40 PM
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Quote:
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that's what I meant to say... is there any clear indication that things like 12-bit color and YCbCr 4:4:4 will be used anytime soon (in the next few years or so)?

While 12-bit color will be useful to make contouring nearly impossible in content mastered for a new standard, 4:4:4 has absolutely ZERO impact on image quality. RGB and YCbCr 4:4:4 contain FAR more color information than the human vision system can perceive. Decimating color to 4:2:2 is perceptually lossless... we can't tell the difference between 4:2:2 video and 4:4:4 video because our color vision simply does not benefit from un-decimated color information. In fact, 4:2:0 is barely detectable compared to 4:4:4. 4:2:2 would produce perfect-looking images if we had that from beginning to end in a home video format.

Now, that's not to say you cannot produce magnified still video frames that show differences between 4:2:0 and 4:2:2 and 4:4:4... but those still-frame differences won't be visible in real-world viewing conditions at home unless your normal viewing mode is to pause images frame-by-frame and examine every detail of every frame before moving on. And they won't even be visible in a full-frame image viewed at any reasonably normal distance... like arm's length for a 4x6 photo or 7 feet from a 60" flat panel TV.

Most people are going to sit too far from their TVs to see much real benefit from 4K just because they have "habits" that are hard to break... like TV on one side of the room, sofa on the other side of the room and whether that results in an 8-foot, 10-foot, 12-foot or larger viewing distance. To benefit from 4K you want to move closer than the optimum distance for HD... and 7 feet for a 60" diagonal flat panel is actually a little far to experience maximum resolution from HDTV. For 4K, you should sit even closer... like 4 feet from the screen for a 60" diagonal display... which is problematic because loudspeakers for home use sound their best when you sit between 7 and 10 feet for decent-size floor standing loudspeakers (a bit closer works for physically smaller speakers). So if you want a great 4K experience, you'll want a 10-foot diagonal screen and sit maybe 8 feet from it. With 4:4:4 vs 4:2:2 you just can't see the difference at all... 4:4:4 requires more bandwidth to transmit with no visual benefit.

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post #26 of 26 Old 09-10-2013, 08:19 AM
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When you perform calculations for UHD, you have to include the blanking. For 3840x2160, the entire raster is really 4400x2250. The rate for 12-bit 4:2:2 would be 14.256 Gbps.

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