Forum Jump: 
 342Likes
Reply
 
Thread Tools
post #1 of 359 Old 04-14-2016, 07:19 PM - Thread Starter
AVS Forum Special Member
 
Scott Wilkinson's Avatar
 
Join Date: Sep 2001
Location: Burbank, CA
Posts: 3,256
Mentioned: 89 Post(s)
Tagged: 0 Thread(s)
Quoted: 1879 Post(s)
Liked: 4884
Determining Display-Panel Bit Depth

In the world of high definition, the brightness of each primary color (red, green, and blue) in each pixel is represented with 8 bits, providing a maximum of 256 discrete brightness levels from 0 to 255. (In practice, consumer-video signals typically use the range from 16 to 235, though the high end sometimes extends above 235.) Combined with specs for peak brightness and color gamut, this is known as standard dynamic range (SDR), and it has worked relatively well for HD and its color gamut of BT.709. All HD displays can accept and render video signals with 8-bit precision.

But Ultra HD includes the possibility of high dynamic range (HDR) and wide color gamut (WCG), and 8 bits per color are no longer sufficient. HDR means there is a greater range from darkest to brightest, and WCG means there is a greater range of colors that can be more saturated than BT.709. If this information is represented and displayed with 8-bit precision, the "distance" between consecutive brightness levels is larger than it is with SDR. The result is clearly visible as banding in areas of the image with gradual gradations in brightness, such as sunsets, blue sky, and underwater shots. Consequently, HDR content is represented with at least 10 bits per color.


The 8-bit version of this image has clear banding, while the 10-bit version does not.

Because of this, you'd think that all HDR-capable displays must have at least 10-bit precision from the input through the electronics to the raw display panel itself, but that is not necessarily true. Of course, the input must be able to accept a signal with at least 10-bit precision, though there are several places along the signal path—such as some HEVC decoders—where the bit depth might be reduced to 8 bits.

Then there's the actual display panel (e.g., LCD, OLED, or projector imager). It turns out that some panels in HDR-capable TVs have 8-bit native precision, because 10-bit panels are more expensive to manufacture and therefore increase the price of the final product.

In a Dither

How can an 8-bit panel—or any other 8-bit step in the signal path—reproduce a 10-bit HDR image without banding? There are two main techniques to do this. One is spatial dithering, in which neighboring pixels are assigned color values in such a way that the banding is obscured. But this sometimes results in visible artifacts such as a checkerboard effect or what looks like noise, so it isn't used much in consumer TVs.

The other, more common technique is temporal dithering, often called frame-rate control (FRC). In this process, a pixel rapidly alternates between two colors to give the impression of a third color. Depending on the specific algorithm used, this can work much better than spatial dithering, but it can also result in visible artifacts such as twinkling, especially in dark areas. Still, this process works so well, it's even used in some professional monitors that are widely used in color grading.

In my recent article listing HDR-capable displays, one of the most heated discussions in the comments is about the native bit depth of the panel used in this or that model of TV. Unfortunately, some manufacturers, such as Samsung and Sony, do not officially reveal the bit depth of the panels in their HDR displays, saying that an 8-bit panel with good processing can perform better than a 10-bit panel with poor processing.

That may well be true, but I maintain that an 8-bit panel is an inherent bottleneck in the HDR signal chain, and compensating for it with dithering—even high-quality dithering—is not as desirable as using a 10-bit panel with good processing. Such a TV is generally more expensive to manufacture and purchase, but in my view, it's worth it to get the best possible HDR image.

Manufacturer Specs

Is it possible to determine the native bit depth of a display's panel? If the manufacturer clearly specifies it, great. But in some cases, a manufacturer's marketing department might not know, or it might be misinformed. And as mentioned earlier, some manufacturers, such as Samsung and Sony, do not officially reveal this information.

One of models most often cited in that heated discussion about HDR-capable displays is the Samsung HU9000, the 2014 flagship UHDTV with no HDR capabilities when it was introduced. Those capabilities were added when owners upgraded the outboard One Connect Evolution Kit to the 2015 SEK-3500. But what is the native bit depth of the HU9000's panel itself?

To answer this question, some AVS members pointed to a video interview from SPSN (Samsung Product Support Network)—a Samsung-sponsored YouTube channel—in which National Product Testing Manager Scott Cohen clearly states that the HU9000 has a 10-bit panel. Also, some members have cited the spec sheet for a replacement panel for the HU9000 from third-party supplier TV Service Parts, which clearly indicates that it's a 10-bit panel.

However, it turns out that the panel within the HU9000 is, in fact, 8-bit, and that Scott Cohen and TV Service Parts were mistakenly misinformed. (There was no intent to deceive; it was a clerical error.) You can verify this by going to Samsung's own replacement-part site and searching for part number BN95-01688A, which is the replacement panel for the UN78HU9000. As you can see on that page, the panel is specified as 8-bit. This info has also been corrected on the TV Service Parts site.





EDID

So is there a way to determine the native bit depth of a TV's panel on your own? Some AVS members use a program like Monitor Asset Manager, which queries the TV about its capabilities via EDID (Extended Display ID). This causes the TV to send information about its capabilities back along the HDMI cable to the computer running the software.



The screen shot above is the result of an AVS member using Monitor Asset Manager with an HU9000 and the 2015 SEK-3500 One Connect Evolution Kit. The EDID reports that the TV supports 30 and 36 bpp (bits per pixel), which translates to 10 and 12 bits per color, respectively. However, this does not reveal anything about the LCD panel's native bit depth, only that the SEK-3500 can accept 10- and 12-bit signals. As we now know, the panel's native bit depth is actually 8 bits, and the SEK-3500 dithers 10- and 12-bit signals to 8 bits.



One member posted the screen shot above from the software control panel of his GeForce 750 graphics card, which was connected to an HU9000 with SEK-3500. The software allowed him to select the card's maximum bit depth for that display, 32 bits per pixel, which was claimed to indicate that the TV can accept a 10-bit signal (30 bpp). However, this probably means that the card can send no more than 24 bpp plus an 8-bit "alpha" channel. Also, if the HDMI bandwidth of this card is 10.2 Gbps (which I haven't yet verified), it can't send any more than 8 bits per color at 4K/60p, as the control panel indicates.

Photos

Some members post photographic screen shots of their TVs showing HDR content to demonstrate that they are HDR-capable—and in some cases, to ask other members if the TV is HDR-capable based on the photos. Unfortunately, this is a completely useless exercise because there are so many unknowns. What's the dynamic range captured by the camera? What's the dynamic range of the monitor or display used to view the photos on AVS? (It's probably not HDR.) There is no well-defined way to do this, so it's not valid proof of anything—except perhaps to illustrate that one TV looks different than another if the photos were taken with the same camera using the same settings under the same conditions.

Test Patterns

Tyler Pruitt (WiFi-Spy), technical liaison at SpectraCal, started a thread in the Display Calibration forum that offers a short test clip with two 2160p 10-bit gradient ramps—that is, 3840x2160 images with smooth gradients from black to white and black to 75% gray created and encoded with 10-bit precision. (The pattern also includes a simulated 8-bit gradient for comparison.) The purpose of the test is to determine if a TV's panel is 10-bit or 8-bit; if it's 8-bit, you should see banding in the image.


Here is one frame from Tyler's 10-bit gradient pattern.

In the same thread, Tyler also included a similar test pattern created by Stacey Spears (sspears), chief color scientist at SpectraCal and co-creator of the Spears & Munsil HD Benchmark set-up Blu-ray. It includes two gradient ramps—one encoded with 10-bit precision and the other with the 10-bit values rounded to 8 bits. Both gradients slowly rotate, which makes it much easier to see any banding.


In this pattern from Stacey Spears, the two gradients rotate to more easily see any banding. The one of the right is encoded with 10-bit precision, and the one on the left uses 10-bit values that have been rounded to 8 bits.

These test patterns are all well and good—in fact, they're excellent—but they do not directly address the question of the raw panel's native bit depth. They only assess the performance of the display system as a whole, including the processing and panel. For example, if the panel has a native bit depth of 8 bits, it might perform these tests well if the dithering algorithm is good.

To illustrate this point, a new test pattern from Stacey includes three rotating gradients—one with 10-bit precision, one with rounded 8-bit values, and one with 8-bit spatially dithered values. The 8-bit rounded pattern should exhibit obvious banding in most cases, while the 10-bit and 8-bit dithered patterns should look close to the same, though the 10-bit should look a bit cleaner because compression filters out some of the dither via quantization.


In this pattern, Stacey illustrates the difference between rounding and dithering 10-bit values to 8 bits. In some cases, such as the Panasonic DX800 LCD TV for the European market, he says the 8-bit dithered pattern actually looks better than the straight 10-bit pattern.

Bottom Line

As Stacey Spears has pointed out to me, there is no way to definitively measure the native bit depth of a display panel without physically dismantling the TV and testing the panel directly, which is clearly impractical. So I'm afraid those who believe that the tests mentioned in this article can provide this information are mistaken. Instead, these tests measure the performance of the system as a whole.

An HDR display with an 8-bit panel and good dithering algorithms can certainly display HDR content in a way that looks better than the best SDR presentation. But I would prefer a panel with a native bit depth of at least 10 bits, along with a signal path that maintains 10-bit precision from one end to the other. I wish there was a foolproof way for consumers to determine this for all displays, but in some cases, there isn't.

Still, the bottom line is how it looks displaying real program material. If you like what you see, there's no need to stress about the panel's bit depth—just sit back and enjoy!

Many thanks to Stacey Spears and Tyler Pruitt of SpectraCal for their generous help with this article.

Note: Please do not quote this entire article when posting a comment. Feel free to quote the relevant portion that pertains to your comment, but wading through the entire thing in the comments is quite annoying. Thanks!

Last edited by Scott Wilkinson; 04-15-2016 at 12:59 PM.
Scott Wilkinson is offline  
Sponsored Links
Advertisement
 
post #2 of 359 Old 04-14-2016, 08:03 PM
AVS Forum Special Member
 
Woobieizer's Avatar
 
Join Date: Jun 2007
Posts: 1,627
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 479 Post(s)
Liked: 228
Thanks Scott, I'll give up the ghost on peering at macros of pixels; counting segments of RGB/RBG. Shucks




I don't mean to split hairs Scott but this is a excerpt of your article.

Quote:
Originally Posted by Scott Wilkinson View Post
(There was no intent to deceive; it was a clerical error.) You can verify this by going to Samsung's own replacement-part site and searching for part number BN95-01688A, which is the replacement panel for the UN78HU9000.
Whereas J & J International is An "Authorized Reseller" the link/site is not Samsungs owned.


Last edited by Woobieizer; 06-17-2016 at 02:32 PM.
Woobieizer is offline  
post #3 of 359 Old 04-14-2016, 08:55 PM
AVS Forum Special Member
 
Woobieizer's Avatar
 
Join Date: Jun 2007
Posts: 1,627
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 479 Post(s)
Liked: 228
You don't know how long we've been waiting for this article

Quote:
Originally Posted by Scott Wilkinson View Post

Bottom Line

As Stacey Spears has pointed out to me, there is no way to definitively measure the native bit depth of a display panel without physically dismantling the TV and testing the panel directly, which is clearly impractical.

Hate being such a nag Scott. But you of all people should know this statement begs the question of HOW. Cause we are not ALL practical members.
Woobieizer is offline  
Sponsored Links
Advertisement
 
post #4 of 359 Old 04-14-2016, 09:48 PM
Member
 
Bloodwound's Avatar
 
Join Date: Apr 2007
Posts: 198
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 128 Post(s)
Liked: 37
Great article but I have to correct you on this point:
Quote:
One member posted the screen shot above from the software control panel of his GeForce 750 graphics card, which was connected to an HU9000 with SEK-3500. The software allowed him to select the card’s maximum bit depth for that display, 32 bits per pixel, which indicates that the TV can accept a 10-bit signal (30 bpp). But again, this applies to what the SEK-3500 can accept; it reveals nothing about the native bit depth of the TV’s LCD panel by itself, which we now know to be 8 bits.
It does NOT indicate that the TV (SEK-3500) can accept 10-bit signal. 32bit is 24bit + alpha. Transparency is handled before it reaches the HDMI output so it's basically the same as 24bit.

Besides, I think it's wrong to assume that a display that accepts 32bit color (if that was true, which it isn't, and it's not even possible for all intents and purposes), would accept a lower "random" bitdepth.

Furthermore HDMI 2.0 @ 40K60 (as the screenshot shows) has only the bandwidth to support 24bit RGB. A higher bitdepth just isn't possible.
zim2411 and nj1420 like this.
Bloodwound is offline  
post #5 of 359 Old 04-14-2016, 10:43 PM - Thread Starter
AVS Forum Special Member
 
Scott Wilkinson's Avatar
 
Join Date: Sep 2001
Location: Burbank, CA
Posts: 3,256
Mentioned: 89 Post(s)
Tagged: 0 Thread(s)
Quoted: 1879 Post(s)
Liked: 4884
Quote:
Originally Posted by Woobieizer View Post
I don't mean to split hairs Scott but this is a excerpt of your article.

Whereas J & J International is An "Authorized Reseller" the link/site is not Samsungs owned.

I'm not sure what you're getting at here...
Scott Wilkinson is offline  
post #6 of 359 Old 04-14-2016, 10:45 PM - Thread Starter
AVS Forum Special Member
 
Scott Wilkinson's Avatar
 
Join Date: Sep 2001
Location: Burbank, CA
Posts: 3,256
Mentioned: 89 Post(s)
Tagged: 0 Thread(s)
Quoted: 1879 Post(s)
Liked: 4884
Quote:
Originally Posted by Bloodwound View Post
Great article but I have to correct you on this point:


It does NOT indicate that the TV (SEK-3500) can accept 10-bit signal. 32bit is 24bit + alpha. Transparency is handled before it reaches the HDMI output so it's basically the same as 24bit.

Besides, I think it's wrong to assume that a display that accepts 32bit color (if that was true, which it isn't, and it's not even possible for all intents and purposes), would accept a lower "random" bitdepth.

Furthermore HDMI 2.0 @ 40K60 (as the screenshot shows) has only the bandwidth to support 24bit RGB. A higher bitdepth just isn't possible.
Very good point! I'll update the article accordingly.
Scott Wilkinson is offline  
post #7 of 359 Old 04-14-2016, 10:48 PM - Thread Starter
AVS Forum Special Member
 
Scott Wilkinson's Avatar
 
Join Date: Sep 2001
Location: Burbank, CA
Posts: 3,256
Mentioned: 89 Post(s)
Tagged: 0 Thread(s)
Quoted: 1879 Post(s)
Liked: 4884
Quote:
Originally Posted by Woobieizer View Post
Hate being such a nag Scott. But you of all people should know this statement begs the question of HOW. Cause we are not ALL practical members.
How what? How does one physically dismantle a screen and measure the bit depth directly? I have no idea, but it's certainly nothing I would ever want to do. I get it that some AVS members would want to do it, but it's up to them to learn how...
Scott Wilkinson is offline  
post #8 of 359 Old 04-15-2016, 12:09 AM
AVS Forum Special Member
 
Woobieizer's Avatar
 
Join Date: Jun 2007
Posts: 1,627
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 479 Post(s)
Liked: 228
Quote:
Originally Posted by Scott Wilkinson View Post
I'm not sure what you're getting at here...
J & J International, the parts site you linked is not owned by Samsung; hence not Samsung's own site.

Quote:
Originally Posted by Scott Wilkinson View Post
How what? How does one physically dismantle a screen and measure the bit depth directly? I have no idea, but it's certainly nothing I would ever want to do. I get it that some AVS members would want to do it, but it's up to them to learn how...
I don't know where you would find the time honestly, even if you had a desire. For sake of thoughtlessness and since it is the mother of all caveats on this subject; challenging the statement made by Stacey Spears of direct panel testing could extinguish all FUD. Imagine if this impractical testing became practical. Would you not want to be the messenger?

I may not be the one that can afford testing equipment, or even have (yet) the technical fortitude.

IMHO a method left unexplained that could be elaborated on; its the elephant in the room.
Woobieizer is offline  
post #9 of 359 Old 04-15-2016, 02:19 AM
AVS Forum Special Member
 
mightyhuhn's Avatar
 
Join Date: Nov 2013
Posts: 1,952
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 1028 Post(s)
Liked: 356
Quote:
Originally Posted by Scott Wilkinson View Post
One member posted the screen shot above from the software control panel of his GeForce 750 graphics card, which was connected to an HU9000 with SEK-3500. The software allowed him to select the card's maximum bit depth for that display, 32 bits per pixel, which indicates that the TV can accept a 10-bit signal (30 bpp). But again, this applies to what the SEK-3500 can accept; it reveals nothing about the native bit depth of the TV's LCD panel by itself, which we now know to be 8 bits.
like said before the 32 bit is with the alpha channel.
but this nvidia page is still a start.

this is the bit deep setting from the same page:
http://abload.de/img/bitdeepsettingscws81.png

unlike AMD you can choice 8 bit or the highest possible which is nearly always 12 bit.
i haven't seen a 1080p screen without 12 bit input support BTW.

sending 10/12 bit to the display is one thing. but getting 10 bit in the GPU driver is another thing. video renderer that can do this are using a fullscreen exclusive directx 10/11 mode the normal windows desktop can't do that.

and all this doesn't mean a display is even 8 bit. 6 bit isn't rare for laptops, very cheap TVs or PC monitors.
VBB likes this.
mightyhuhn is online now  
post #10 of 359 Old 04-15-2016, 06:01 AM
AVS Forum Special Member
 
thomasfxlt's Avatar
 
Join Date: Nov 2009
Posts: 4,880
Mentioned: 117 Post(s)
Tagged: 0 Thread(s)
Quoted: 3254 Post(s)
Liked: 6062
Nice Job Scott!

SONY Z9F LCD Master Series Owners Thread
Vizio 2016 P series FAQ, general info and Help
Sony Z9F 75, Vizio P75C1 UHD/HDR/DV, Pioneer Elite SC-95, Samsung UHD Bluray K8500, AppleTV 4K, CC Ultra
thomasfxlt is online now  
post #11 of 359 Old 04-15-2016, 06:09 AM
AVS Forum Special Member
 
6athome's Avatar
 
Join Date: Mar 2006
Posts: 1,523
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 630 Post(s)
Liked: 172
Scott it was nice to know that a Vizio representative was honest and forthright in the new P series being 10 bit all the way from the internal 10 bit processing to the 10 bit panel.
When the first Vizio P series came out, I found out that it had a 10 bit Sharp 70 inch panel, but was unsure about the internal processing.
GrandPixel likes this.
6athome is offline  
post #12 of 359 Old 04-15-2016, 06:49 AM
 
RLBURNSIDE's Avatar
 
Join Date: Jan 2007
Posts: 3,901
Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 2012 Post(s)
Liked: 1401
Excellent breakdown! This, like many others on the front page at AVS, should be considered required reading for graphics industry professionals IMO, and even consumers who want a little help in decoding the acronym soup.

I think 10bit over 8bit is far more important, even for 1080p SDR, than UHD resolution is on its own.

With AMD Polaris supporting HDR via HDMI 2.0a and DisplayPort 1.3 officially, and windows 10 also adding support for HDR on the desktop in 2017, things are moving along nicely. Especially when you add in the super cheap 55 inch Vizio P series that does 10bit as well as 120hz (if I'm not mistaken) at 1080p. This is fantastic for gamers. Higher framerate and higher bit depth are far more crucial to gaming than static resolution.

Especially since motion resolution on these LCDs doesn't even pass FHD (even on FALD sets). Actually, Scott, for a follow up article, I think it would be a good idea to delve into what the motion resolution on all these UHD TVs is, because it's a recurring theme on this forum that people refer to UHD as if its benefits are visible during motion. As soon as you have even 1 pixel of added motion blur coming from the display itself, you've immediately dropped from UHD to FHD levels of motion resolution. Watching static screenshots is not what most people use their TVs for, aside from gamers, who play games that aren't static either. Although, to be fair to UHD movies, most movie scenes are shot with the camera held motionless so that at least objects that are in focus do benefit from static resolution. The question is, how often is that? Things in the foreground like people are usually in motion, ergo motion blur from low framerate. Even at 60hz UHD on a movie or TV show, there is added motion blur from the TV itself and that's where I get dubious about UHD mattering much. We all know that UHD barely matters in static resolution at most seating distances, but in motion resolution? I don't think it matters at all. However I'd like to see some hard data on it. Most LCDs AFAIK only do 300 lines of motion resolution, or perhaps 600 with FALD and 120hz panels. That's not even FHD let alone UHD.

I'm not anti-UHD I just want to spend my GPU resources where they count (on higher framerate and bit depths at 1080p instead).
RLBURNSIDE is offline  
post #13 of 359 Old 04-15-2016, 10:43 AM
AVS Forum Special Member
 
KidHorn's Avatar
 
Join Date: Nov 2003
Location: Derwood, Maryland
Posts: 5,205
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 1733 Post(s)
Liked: 1151
Great. So there's no easy way to tell what the bit depth of a panel is. Manufacturers can lie or be mistaken and no one can tell.

I guess we'll just have to rely on picking that TV that has the best picture in our price and size range.
Woobieizer likes this.
KidHorn is offline  
post #14 of 359 Old 04-15-2016, 11:29 AM
Super Moderator
 
markrubin's Avatar
 
Join Date: May 2001
Location: Jersey Shore
Posts: 20,925
Mentioned: 48 Post(s)
Tagged: 0 Thread(s)
Quoted: 1653 Post(s)
Liked: 3377
no doubt AVS members can figure this out...and post a spreadsheet on the results...it would be a work in progress

we are all entitled to this information
Woobieizer likes this.

please take the high road in every post:do not respond to or quote a problematic post: report it
HDMI.org:what a mess
HDCP = Hollywood's Draconian Copy Protection system

markrubin is offline  
post #15 of 359 Old 04-15-2016, 12:03 PM - Thread Starter
AVS Forum Special Member
 
Scott Wilkinson's Avatar
 
Join Date: Sep 2001
Location: Burbank, CA
Posts: 3,256
Mentioned: 89 Post(s)
Tagged: 0 Thread(s)
Quoted: 1879 Post(s)
Liked: 4884
Quote:
Originally Posted by Woobieizer View Post
J & J International, the parts site you linked is not owned by Samsung; hence not Samsung's own site.
Ah, well, it may be a third-party site, but Samsung must contract with them to provide replacement parts.

Quote:
Originally Posted by Woobieizer View Post
I don't know where you would find the time honestly, even if you had a desire. For sake of thoughtlessness and since it is the mother of all caveats on this subject; challenging the statement made by Stacey Spears of direct panel testing could extinguish all FUD. Imagine if this impractical testing became practical. Would you not want to be the messenger?

I may not be the one that can afford testing equipment, or even have (yet) the technical fortitude.

IMHO a method left unexplained that could be elaborated on; its the elephant in the room.
Such a method is way beyond the scope of this article, and certainly way beyond the capabilities of most AVS members. Not all members, of course, but certainly most. And I seriously doubt that it will ever become practical, since dismantling a TV will never be an easy task, and I would never recommend it for anyone but a trained, professional technician. If you don't know exactly what you're doing, it seems to me that you could easily "brick" the TV. Also, as you point out, there's the issue of the testing equipment, which is undoubtedly expensive and out of reach for most members. So in my view, elaborating on this procedure would be pointless. If someone else wants to do so, go for it!
Scott Wilkinson is offline  
post #16 of 359 Old 04-15-2016, 12:09 PM - Thread Starter
AVS Forum Special Member
 
Scott Wilkinson's Avatar
 
Join Date: Sep 2001
Location: Burbank, CA
Posts: 3,256
Mentioned: 89 Post(s)
Tagged: 0 Thread(s)
Quoted: 1879 Post(s)
Liked: 4884
Quote:
Originally Posted by KidHorn View Post
Great. So there's no easy way to tell what the bit depth of a panel is. Manufacturers can lie or be mistaken and no one can tell.

I guess we'll just have to rely on picking that TV that has the best picture in our price and size range.
Exactly!
Scott Wilkinson is offline  
post #17 of 359 Old 04-15-2016, 12:18 PM - Thread Starter
AVS Forum Special Member
 
Scott Wilkinson's Avatar
 
Join Date: Sep 2001
Location: Burbank, CA
Posts: 3,256
Mentioned: 89 Post(s)
Tagged: 0 Thread(s)
Quoted: 1879 Post(s)
Liked: 4884
Quote:
Originally Posted by markrubin View Post
no doubt AVS members can figure this out...and post a spreadsheet on the results...it would be a work in progress

we are all entitled to this information
I'm afraid that, in some cases, it will be impossible to figure out completely without analyzing each and every step in the signal path, which would mean dismantling a TV and employing expensive test gear, a very time-consuming process that requires lots of training. How many AVS members have that capability, and how many of those are going to actually take the time to do it?

We may be entitled to this information, but that doesn't mean we can actually determine it; life is sometimes unfair. On the other hand, AVS members have surprised me on many occasions, so who knows? Maybe such a spreadsheet will appear. One can hope...
markrubin likes this.
Scott Wilkinson is offline  
post #18 of 359 Old 04-15-2016, 12:27 PM - Thread Starter
AVS Forum Special Member
 
Scott Wilkinson's Avatar
 
Join Date: Sep 2001
Location: Burbank, CA
Posts: 3,256
Mentioned: 89 Post(s)
Tagged: 0 Thread(s)
Quoted: 1879 Post(s)
Liked: 4884
Quote:
Originally Posted by 6athome View Post
Scott it was nice to know that a Vizio representative was honest and forthright in the new P series being 10 bit all the way from the internal 10 bit processing to the 10 bit panel.
I applaud Vizio for being very transparent about this, and I wish other manufacturers would follow suit.
MCaugusto likes this.
Scott Wilkinson is offline  
post #19 of 359 Old 04-15-2016, 12:37 PM
AVS Forum Special Member
 
helvetica bold's Avatar
 
Join Date: Oct 2004
Location: NYC
Posts: 1,906
Mentioned: 1 Post(s)
Tagged: 1 Thread(s)
Quoted: 1158 Post(s)
Liked: 663
Great article Scott! l own Sony's 2013 KDL 55W900a. It's one of the first Quantum Dot (by QD Vision) TVs and I always wondered what is the panel bit depth. The TV has beautiful PQ so much so that I see no need to upgrade to 4K anytime soon. Anyway, I sent a tweet to Color IQ (QD Vision) and they kindly replied that the W9 is a "true 10 bit display". Now they provided Sony with the QD tech so I figured they would know! But you know what, Im still skeptical but who really knows! Im just enjoying my TV.
helvetica bold is online now  
post #20 of 359 Old 04-15-2016, 01:31 PM
AVS Forum Special Member
 
poppagene's Avatar
 
Join Date: Apr 2006
Location: Bethesda. MD
Posts: 1,472
Mentioned: 31 Post(s)
Tagged: 0 Thread(s)
Quoted: 817 Post(s)
Liked: 658
Quote:
Originally Posted by Scott Wilkinson View Post
One of models most often cited in that heated discussion about HDR-capable displays is the Samsung HU9000, the 2014 flagship UHDTV with no HDR capabilities when it was introduced. Those capabilities were added when owners upgraded the outboard One Connect Evolution Kit to the 2015 SEK-3500. But what is the native bit depth of the HU9000's panel itself?

To answer this question, some AVS members pointed to a video interview from SPSN (Samsung Product Support Network)—a Samsung-sponsored YouTube channel—in which National Product Testing Manager Scott Cohen clearly states that the HU9000 has a 10-bit panel. Also, some members have cited the spec sheet for a replacement panel for the HU9000 from third-party supplier TV Service Parts, which clearly indicates that it's a 10-bit panel.

However, it turns out that the panel within the HU9000 is, in fact, 8-bit, and that Scott Cohen and TV Service Parts were mistakenly misinformed. (There was no intent to deceive; it was a clerical error.) You can verify this by going to Samsung's own replacement-part site and searching for part number BN95-01688A, which is the replacement panel for the UN78HU9000. As you can see on that page, the panel is specified as 8-bit. This info has also been corrected on the TV Service Parts site.


Note: Please do not quote this entire article when posting a comment. Feel free to quote the relevant portion that pertains to your comment, but wading through the entire thing in the comments is quite annoying. Thanks!

FWIW, your illustration is for the 78 incher. If you go to Samsung Parts (your source) and look for the UN65HU9000 panel

http://www.samsungparts.com/PartsLis...ch=BN95-01379A

or for the UN55HU9000

http://www.samsungparts.com/Products...95-01378A.aspx

both say 10 bit

Disclaimer, I don't own an HU9000 nor do I have a panel listed as 10 bit on either part site.

Quote:
Originally Posted by Scott Wilkinson View Post
Note: Please do not quote this entire article when posting a comment. Feel free to quote the relevant portion that pertains to your comment, but wading through the entire thing in the comments is quite annoying. Thanks!
The above note is spot on and should be added to all posts over a certain length.

UN48JS8500 UN55HU6950 w/SEK-3500U UN40HU6950 w/SEK-3500U UBD-K8500 UN37C5000
poppagene is online now  
post #21 of 359 Old 04-15-2016, 02:01 PM
AVS Forum Special Member
 
Woobieizer's Avatar
 
Join Date: Jun 2007
Posts: 1,627
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 479 Post(s)
Liked: 228
Quote:
Originally Posted by markrubin View Post
no doubt AVS members can figure this out...and post a spreadsheet on the results...it would be a work in progress

we are all entitled to this information
We actually have members that keep the books. One such member keeps presence on SetComb and here @hristoslav2 , manages to keep up a Samsung library, so to speak, yet is his observations and research are not limited to just Samsung. His work will be no stranger to those that frequent Samsung Panel Version Thread or just google about some keywords. .


Using SamsungParts, Panelook and samsungonderdelen.com for research into parts is no stranger to most on this site. I stumbled upon my own answers researching a HDTV As far back as 12/19/2013 using just this technique.

Nothing's more encouraging than crowd sourcing information to help push the envelope. One might yet punch thru and answer the question How to Determine Display-Panel Bit Depth. Till then it's back to the my corner of AVS.
markrubin and Mike_WI like this.

Last edited by Woobieizer; 06-17-2016 at 02:32 PM.
Woobieizer is offline  
post #22 of 359 Old 04-15-2016, 03:41 PM
Advanced Member
 
Larry Rosenberg's Avatar
 
Join Date: Feb 2016
Location: Los Angeles, California
Posts: 557
Mentioned: 21 Post(s)
Tagged: 0 Thread(s)
Quoted: 458 Post(s)
Liked: 334
Quote:
Originally Posted by Scott Wilkinson View Post
Bottom Line

Still, the bottom line is how it looks displaying real program material. If you like what you see, there's no need to stress about the panel's bit depth—just sit back and enjoy!
Wonderful article! Wow. This goes a long way to fill the void and end the guessing games that "early adapters" were prone to do, especially after investing in very expensive and "future proof" 4k TVs only to find out a year later that 4k isn't important unless their TV also does HDR - with a 10 bit panel.

Having just added the Samsung K8500 4K/HDR Blu Ray Player to my UN65HU9000, after adding the SEK 3500 to that, I can say that 4k/HDR discs look amazing and that by the criteria I read here, the TV is, indeed, reading and displaying HDR. So I will also say that Samsung basically kept its word to us about "the future" when this TV was marketed that with the addition of a new HDMI connection box, it would not soon become obsolete.

Are there now/will there later be better TVs? Of course and I will no doubt be interesting in buying one someday, but whether my panel is 8 or 10 bit, it still is the best looking TV I have ever owned and continues to amaze with 4K discs and HDR with the SEK 3500, as promised when we purchased it. That really is all that is important to me as a consumer.
nc88keyz and poppagene like this.

Last edited by Larry Rosenberg; 04-15-2016 at 04:09 PM.
Larry Rosenberg is offline  
post #23 of 359 Old 04-15-2016, 04:45 PM
Member
 
JakeRobb's Avatar
 
Join Date: Mar 2012
Location: Okemos, MI
Posts: 111
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Liked: 14
It seems to me like those test patterns are looking in the wrong place.

High dynamic range, compared tonstandard, accommodates TWO notable differences with its 4x increase in the number of colors it can represent (2^8 = 256, whereas 2^10 = 1024).

The first difference is that the difference between two "adjacent" colors is smaller. This is why a 10-bit system can display those sunset pictures without banding, and banding is what all of the test patterns are testing for. However, because an 8-bit panel has colors available on both "sides" of all of these new HDR colors, temporal dithering makes it possible to switch back and forth quickly between SDR colors on either side of the intended color.

But HDR also brings with it colors entirely outside the range available in SDR -- especially in the greens. There are much "brighter" greens available in HDR than in SDR (note: "brighter" is not necessarily the correct technical term). There's no way for temporal dithering to simulate these extra-bright greens, and so all you can do on an 8-bit panel is pick the closest green available and stick with it. You could test this with a trivial pattern: two large, green regions, where one is specified at the extreme of SDR color space, and the other at the extreme of HDR color space. On an 8-bit panel, I'm pretty sure you would see one large region, all the same color; on a 10-bit panel, they would be clearly differentiated.

Maybe I'm wrong about this; someone please tell me why. I figure, if I am wrong, it's because there's a way to dither to this extra color and I don't know enough about color science to recognize it.

I've attached an image representing the difference in the color space, showing that green has the most potential increase in range. Note that nearly all of us will be viewing this on SDR displays, and, in fact, the PNG I uploaded is encoded with 8-bit color, so you can't actually see what's so special about the extra greens in this image. It's just to illustrate my point.
Attached Thumbnails
Click image for larger version

Name:	AAEAAQAAAAAAAAVIAAAAJDE2MjM3MmM4LTgwMDktNGNhZi05MDQ0LTk2YTdmNWUxZmUzNg.png
Views:	1018
Size:	163.4 KB
ID:	1382690  

Living Room: Denon 2113ci + BIC V1020 + Panasonic BDT220 + AppleTV + uVerse DVR + Panasonic P42S2 plasma
Theater: Denon 2313ci + Klipsch RW12d + Panasonic BDT220 + Mac mini + uVerse wired receiver + Epson 8350 PJ + 100" screen

Last edited by JakeRobb; 04-15-2016 at 04:50 PM. Reason: Added image
JakeRobb is offline  
post #24 of 359 Old 04-15-2016, 07:36 PM - Thread Starter
AVS Forum Special Member
 
Scott Wilkinson's Avatar
 
Join Date: Sep 2001
Location: Burbank, CA
Posts: 3,256
Mentioned: 89 Post(s)
Tagged: 0 Thread(s)
Quoted: 1879 Post(s)
Liked: 4884
Quote:
Originally Posted by poppagene View Post
FWIW, your illustration is for the 78 incher. If you go to Samsung Parts (your source) and look for the UN65HU9000 panel

http://www.samsungparts.com/PartsLis...ch=BN95-01379A

or for the UN55HU9000

http://www.samsungparts.com/Products...95-01378A.aspx

both say 10 bit

Disclaimer, I don't own an HU9000 nor do I have a panel listed as 10 bit on either part site.
I will alert Samsung to the fact that the smaller replacement panels are still listed as 10-bit. I'm sure they will correct that error as well.
Scott Wilkinson is offline  
post #25 of 359 Old 04-15-2016, 07:41 PM - Thread Starter
AVS Forum Special Member
 
Scott Wilkinson's Avatar
 
Join Date: Sep 2001
Location: Burbank, CA
Posts: 3,256
Mentioned: 89 Post(s)
Tagged: 0 Thread(s)
Quoted: 1879 Post(s)
Liked: 4884
Quote:
Originally Posted by Woobieizer View Post
We actually have members that keep the books. One such member keeps presence on SetComb and here @hristoslav2 , manages to keep up a Samsung library, so to speak, yet is his observations and research are not limited to just Samsung. His work will be no stranger to those that frequent Samsung Panel Version Thread or just google about some keywords. .


Using SamsungParts, Panelook and samsungonderdelen.com for research into parts is no stranger to most on this site. I stumbled upon my own answers researching a HDTV As far back as 12/19/2013 using just this technique.

Nothing's more encouraging than crowd sourcing information to help push the envelope. One might yet punch thru and answer the question How to Determine Display-Panel Bit Depth. Till then it's back to the my corner of AVS.
This is great! However, if he and others are relying on manufacturer-supplied information (which I assume they must be, at least for certain pieces of info), that info cannot necessarily be considered foolproof, as we've seen in this article.
Scott Wilkinson is offline  
post #26 of 359 Old 04-15-2016, 07:47 PM
AVS Forum Special Member
 
HockeyoAJB's Avatar
 
Join Date: Dec 2013
Posts: 2,024
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 976 Post(s)
Liked: 816
Quote:
Originally Posted by JakeRobb View Post
It seems to me like those test patterns are looking in the wrong place.

High dynamic range, compared tonstandard, accommodates TWO notable differences with its 4x increase in the number of colors it can represent (2^8 = 256, whereas 2^10 = 1024).

The first difference is that the difference between two "adjacent" colors is smaller. This is why a 10-bit system can display those sunset pictures without banding, and banding is what all of the test patterns are testing for. However, because an 8-bit panel has colors available on both "sides" of all of these new HDR colors, temporal dithering makes it possible to switch back and forth quickly between SDR colors on either side of the intended color.

But HDR also brings with it colors entirely outside the range available in SDR -- especially in the greens. There are much "brighter" greens available in HDR than in SDR (note: "brighter" is not necessarily the correct technical term). There's no way for temporal dithering to simulate these extra-bright greens, and so all you can do on an 8-bit panel is pick the closest green available and stick with it. You could test this with a trivial pattern: two large, green regions, where one is specified at the extreme of SDR color space, and the other at the extreme of HDR color space. On an 8-bit panel, I'm pretty sure you would see one large region, all the same color; on a 10-bit panel, they would be clearly differentiated.

Maybe I'm wrong about this; someone please tell me why. I figure, if I am wrong, it's because there's a way to dither to this extra color and I don't know enough about color science to recognize it.

I've attached an image representing the difference in the color space, showing that green has the most potential increase in range. Note that nearly all of us will be viewing this on SDR displays, and, in fact, the PNG I uploaded is encoded with 8-bit color, so you can't actually see what's so special about the extra greens in this image. It's just to illustrate my point.
You are half right. It is true that a panel with a smaller color gamut cannot use dithering to reproduce colors outside of its gamut. As you mentioned, it can only use dithering to reproduce a color that lies between two colors that the panel is otherwise capable of reproducing. However, the size of a display's native color gamut has no direct connection to its bit depth. An 8-bit panel can have a wider color gamut than a 10-bit panel. Therefore, you can't determine bit depth by looking at the size of the color gamut.
King Richard likes this.
HockeyoAJB is offline  
post #27 of 359 Old 04-15-2016, 07:52 PM
AVS Forum Special Member
 
Woobieizer's Avatar
 
Join Date: Jun 2007
Posts: 1,627
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 479 Post(s)
Liked: 228
Wink

Quote:
Originally Posted by Scott Wilkinson View Post
This is great! However, if he and others are relying on manufacturer-supplied information (which I assume they must be, at least for certain pieces of info), that info cannot necessarily be considered foolproof, as we've seen in this article.
Precisely why we try our best to cross reference information and ask the supposed authorities to help.
Woobieizer is offline  
post #28 of 359 Old 04-15-2016, 07:54 PM
AVS Forum Special Member
 
poppagene's Avatar
 
Join Date: Apr 2006
Location: Bethesda. MD
Posts: 1,472
Mentioned: 31 Post(s)
Tagged: 0 Thread(s)
Quoted: 817 Post(s)
Liked: 658
Quote:
Originally Posted by Scott Wilkinson View Post
I will alert Samsung to the fact that the smaller replacement panels are still listed as 10-bit. I'm sure they will correct that error as well.
If it is an error.

UN48JS8500 UN55HU6950 w/SEK-3500U UN40HU6950 w/SEK-3500U UBD-K8500 UN37C5000
poppagene is online now  
post #29 of 359 Old 04-15-2016, 08:57 PM
AVS Forum Special Member
 
Woobieizer's Avatar
 
Join Date: Jun 2007
Posts: 1,627
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 479 Post(s)
Liked: 228
Placemarker to see if the product codes and descriptions change.

Quote:
Originally Posted by poppagene View Post
If it is an error.
Screenshots for future reference. Duct referenced as 10bit.. Tcon referenced as 8bit

Spoiler!

Last edited by Woobieizer; 06-17-2016 at 02:32 PM.
Woobieizer is offline  
post #30 of 359 Old 04-16-2016, 12:07 AM - Thread Starter
AVS Forum Special Member
 
Scott Wilkinson's Avatar
 
Join Date: Sep 2001
Location: Burbank, CA
Posts: 3,256
Mentioned: 89 Post(s)
Tagged: 0 Thread(s)
Quoted: 1879 Post(s)
Liked: 4884
Quote:
Originally Posted by Scott Wilkinson View Post
I will alert Samsung to the fact that the smaller replacement panels are still listed as 10-bit. I'm sure they will correct that error as well.
Quote:
Originally Posted by poppagene View Post
If it is an error.
I'm certain that it is an error. I've alerted Samsung to it; they say they will correct it on their parts site and inform third-party sites.
Scott Wilkinson is offline  
Sponsored Links
Advertisement
 
Reply High Dynamic Range (HDR) & Wide Color Gamut (WCG)

Tags
<<. , bit depth , hdr



Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off