sRGB to wide gamut mapping in GPU?

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Warpscan

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With vast amount of wide gamut monitors available on the market but still using mostly sRGB for most of the contents (including games), isn't there a need for GPU solution to map sRGB to wide gamut space?

I know that most monitors have sRGB settings, but on mine Dell U2713H wide gamut, uniformity compensation only works on wide gamut (the only reason I was willing to throw close to a $1000 for a monitor was the "screen uniformity compensation")

some apps (photoshop) can remap color space but this is done in the software and things slow down.

I've looked at Radeon HD 6800 or 7700 (or higher) series having claims to linearly convert sRGB color space to wide gamut space. But has anybody tested this?.
Have anybody tried aforementioned AMD cards to compensate for wide gamut?
 
I am afraid i am not going to make a helpful contribution, but it needs to be said:
PEOPLE SHOULD USE A MONITOR WITH THE SAME COLOR GAMUT OF THE CONSUMER.

I am tired of being forced to consume videos and games designed in " high color gamut" monitors. There is simply no way to make content produced in a high color gamut monitor to look good in normal gamuts monitors. And the reverse can be even worse: use a high gamut monitor to emulate a lower gamut one for content production.
A friend of mine runs a small marketing company and has quite a few times tried to make me sell my Apple 30". Every single time i explain that webmarketing content must be produced and color calibrated at a 1080p TN panel, that is, afetr all, the type of screen that most target audience will use to read the content.

As far as i understand software color compensations are gimmicks that either display saturated/ wrong colors or end up with a smaller number of color tones to work with.

In 2005 there was a low cost CCFL backlight capable of high color gamut. delll upgraded the 3007 and months later apple didi the same. After that using high color CCFLs became "mainstream", and people started to buy high color monitors thinking they would get a better image, but instead they were got a display that showed the wrong colors for 99,9999% of everything they used.

Unless the work is to produce printable content, there is no reason any sane professional would opt for a high color gamut monitor. Still, web get lots and lots of gaming and web desingners spending thousands of dollars of corporate money to delivers us consumers games and webpages with wrong color spaces.
 
I agree that wide gamut should be for professionals that use prints as their target medium.
For video game graphics pro like me should use stndard gamut (sRGB).

But only reason I was willing to spend extra $300 for wide gamut is "uniformity compensation"
Since my other 2 PVA and 2 IPS monitors all have color uniformity problem across screen (I knwo its the nature of the beast). yellowish or pinkish tinge to the left, or lower corner...etc
I was willing to spend extra chunk of money to guarantee I get uniform color across screen. But high end wide gamuts are the only ones with uniform compensation...

At current state of LCD mfg technology, 22" or smaller IPS do have acceptable color uniformity across entire screen. for 27" 2560x1440 we are not even close.
 
Hello. I don't think I've ever heard of such a specific feature native to any of the newer AMD Radeon graphics cards - of course I could just be out of the loop, but maybe they're referring to powerstrip? It's a program that creates a LUT based on whatever color profile is being used and writes it to the GPU, at which point you can block changes from external programs.
 
Warpscan. If its a problem why not run the screen in sRGB mode? Have you even confirmed or verified the uniformity compensation feature is doing anything at all? Looking at results in reviews it doesn't seem to function on the U2713H so may be nothing more than a gimmick / placebo anyway.
 
M$ and VGA manufacturers should pay more attention to color management imho. If M$ demanded such feature for it's new Windows then we would have it. If AMD or NV made such feature we would have it. But as it is now, only means to correct colors system wide is 2D-LUT and it's not even working everywhere because games override it most of the time

It would be possible to make OS level or driver level 3D-LUT that would do the job and then any wide-gamut monitor would be sRGB monitor in every application. Either HW or SW solution would be acceptable. But as it is right now nobody care at all...

But there is a catch. 2D-LUT and 3D-LUT also will always introduce banding which is especially visible on 8bit connections (no consumer level VGA support >8bit on digital connection !) so it would not be perfect solution anyway. Nothing beats native gamut emulation of monitor (that is if it's done right)

BTW. is this uniformity compensation any good on this Dell ?
 
Drags,
Something is not right with the TFTCentral review on U2713H perhaps because they are reviewing version A01 whereas mine is version A00. They observed that uniformity compensation is availabel for both sRGB and wide gamut but they confirmed that it doesn't do anything. However on my U2713H (rev A00), the uniformity function does work dramatically! however only works on "standard" preset which is wide gamut and 50% bright & constrast.

After further research, there are no claims from AMD nor Nvidia to support wide gamut to sRGB re-mapping in GPU LUT. Only thing I can find is literature on AMD HD7700 series: page 18 on following link.
http://www.amd.com/us/Documents/DisplayTechnology_whitepaper.pdf
But it only must be implemented in the hardware and there are no drivers to support this yet...

I guess I'll just use sRGB mode without the uniform compensation:(
 
Warpscan said:
...Have anybody tried aforementioned AMD cards to compensate for wide gamut?
Click to expand...
I've got a Radeon 6870 running an HP ZR30w (wide gamut.) In the Catalyst Control under Color Temp there is a checkbox to "use extended display data (EDID)." With this checked, it quite effectively neutralizes the over-saturation due to wide gamut. I don't know if this is the intended effect or just a happy by-product, but for practical purposes it appears to me to be remapping to sRGB. (Whether it is happening in "linear" or "non-linear" space as in that white paper, I've no clue... I don't see any gradient banding.) I've also got a ZR2740w, and it makes the two panels look very comparable. (Without the EDID, I would consider the ZR30w essentially unusable.)

I briefly had a Dell U2711, I couldn't deal with the wide gamut, and the sRGB mode looked like crap, basically just knocking down the saturation on everything. The ZR30w (with EDID) takes down the hot primary colors, but leaves the midrange stuff looking as it should. It definitely looks better than the Dell did in sRGB mode. Unfortunately I didn't have the Radeon at the time, so I can't say for sure how it will work with Dell, but it is worth a shot imho.


geok1ng said:
...and has quite a few times tried to make me sell my Apple 30". Every single time i explain that webmarketing content must be produced and color calibrated at a 1080p TN panel, that is, afetr all, the type of screen that most target audience will use to read the content....dell upgraded the 3007 and months later apple didi the same.
Click to expand...
I'm not quite following your comments on the ACD, are you saying it is a TN panel? Or wide-gamut? As far as I know, the Apple 30" has always been IPS, standard gamut. In general I think content production on a 100% sRGB IPS panel is the way to go. And the 30" ACD would qualify in that regard. Or something like the HP ZR2740w or Dell U2713HM. I don't think you want to be calibrating content to a TN panel... having one on hand to check against isn't a bad idea, but you can't anticipate the average user's crappy screen. I do agree that many of the wide gamut displays out there are quite likely not being managed correctly, and they really have not much use outside of a professional print environment. (well, and for Warpscan, apparently.) ;)
 
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Warpscan said:
Drags,
Something is not right with the TFTCentral review on U2713H perhaps because they are reviewing version A01 whereas mine is version A00. They observed that uniformity compensation is availabel for both sRGB and wide gamut but they confirmed that it doesn't do anything. However on my U2713H (rev A00), the uniformity function does work dramatically! however only works on "standard" preset which is wide gamut and 50% bright & constrast.
Click to expand...


What I mean is, have you actually verified it's doing anything in practice. I know the screen takes a hit in contrast when the feature is turned on and will change in appearance as a result. However it may not actually be doing anything to change the uniformity variation in real life

TFTCentral did test it in standard preset too and at default settings including 50% brightness with same results. That's linked in the review too. Anyway it's pretty pointless if you can only use it at default brightness as that's far too high and standard mode isn't really very accurate anyway

Would have thought you'd be better using sRGB like you say without the feature. It may not have been doing anything other than dropping your contrast anyway :)
 
...Sorry forum seemed to crash and decided to repost me three times!
 
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On revA00, yes the uniformity comepnsation does work:
The overall brightness does dim a little from default 50% but thats not what Im talking about.
color consistency is much more uniform (tested with gray, white: most offending colors for typical IPA panels) across entire panel. luminance too is much more consistent across the screen.

And I undertand your skeptism I may just repoting "dimming" as "working" Not so.
Im very sensitive to color hue shifts as I have PVA, MVA + 2 IPA monitors as result.
 
AMD video cards years ago (then ATI) used to have post-processing filters in the driver that could apply effects like greyscale to everything (including games). I don't know what happened to that since perhaps it would have been great for color corrections.

Monitors using a wide gamut like AdobeRGB can't be mapped down to sRGB using 1D look-up-tables because the AdobeRGB primaries are actually different hues and not just more saturated sRGB primaries. A 3D LUT solves this problem nicely, though typically only very high-end monitors have it and good calibration data is needed to build the LUT. I wish AMD/Nvidia would implement a way to force a color transformation onto everything output to each display, but considering how many bugs there are just with color profile handling right now I'm not holding my breath.
 
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