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I recently replaced my laptop screen, and when it was first installed, its color was too greenish. I go into Windows 10 and use dccw.exe(a windows built-in color calibration tool) adjust the gamma and RGB of the display by looking at some pictures with the naked eye, so that the screen displayed more normal. And then dccw generated an icc profile. Later, I go into Pop OS, imported the icc profile to gnome's settings->color, and gnome told me "full screen display correction not possible with this profile". So I'm now looking for other ways to adjust the display color on linux.

I am not an artist, I just want my screen to display a bit more normal, so I don't plan to buy any hardware, it would be too much trouble. Pop OS did Pre-installed NVIDIA driver, but my laptop are using Intel core graphics output, NVIDIA graphics calculation, so the NVIDIA X Server Settings told me the display can't control by nvidia. I have also tried searching the icc profile shared by others on the Internet. I can’t find the model of mine(BOE NV156FHM-N69), only find the NV156FHM-N61 and used it. The effects not perfect but ok, but I prefer to customize by self. I've also tried redshift and gnome night lights, and customized color temperature, but it's not as good as using other screens' icc profile. I wonder if there is a better and easier way customize the display color RBG and Gamma like using dccw.exe on windows.

Any thoughts and ideas on that topic would be highly appreciated.

Thanks in advance!

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Scroll down to #9 if you know basics.

  1. colour is a thing created by weighted RELATIVE measurement in the human brain. It is per-human specific, and very dependent on ambient light conditions (luminant). Even a thin tinted paper sheet at the back of the monitor influences perception.

  2. CIE has developed methods and references of measuring colour in a way that most people may compare, and find acceptable for perception.

  3. ICC has developed methods and formats of characterising devices using CIE measurement methods. There is no difference, where you have created ICC files, in Windows, Linux or MAC. So you can try Windows tools without worry.

  4. HP and MS under IEC has developed standards (main is sRGB) of colour and brightness scale measured by CIE rules, which may be managed using ICC methods.

//it was based on typical CRT screen electron beam voltage to brightness transfer function, and initially on colour reproduction space (gamut) of some mediocre RGB display from 80s. The other common brightness transfer function is gamma-exponent in the power of 2.2.

//Apple never follows other specialists' efforts and was using gamma 1.8, making people climb on the wall. Still the high quality of Mac software, and uncertainty of 80s computing, allowed the 1.8 standard to infiltrate the professional market.

  1. The device conforming to 2.2, or sRGB, which are almost the same, may show different colours when comparing to another device placed nearby. That is because of different "luminant" characteristics of CRT phosfor, Light diode, or CCFL lamp; the same goes for white paper of different tint under different ligh conditions.

  2. For comparative equivalence you can correct your monitor/printer per-channel colour reproduction, bringing it closer to standard lluminant. Common luminants are D50 (5000K colour temp) for paper printing, D65 (6500K) for monitor(image editing), and D75 (7500K) often suitable for common gamers and video watchers. Please keep in mind that natural backlight of LCD monitors and TVs can climb as high as 9000K, so the calibrated panels are tightly squeezed in colour reproduction in order to bring them down to common colours. In addition, you can apply more rigorous correction at PC side.

//But it does not mean that 9000K is bad. For nonprofessional purpose, high colour temperature monitors generally produce stronger and deeper color perception of an image; most consumers find "bluish white" more white than "yellowish white" outdoors (D65). The BEST CRT monitors in 2000s from Hitachi had typical color temp as high as 9300K, with corresponding ICC profiles shipped along. When viewing such monitors you could fall to nirvana. But you could never get the same result as on paper or on TV when editing content. So people were often using a TV attached in parallel for color proofing. That's why TV component outputs were popular in 90s and 2000s.

  1. Bringing your colour reproduction to standard requires a CIE conformant measurement equipment. Generally a "calibrator" (x-rite or spider, etc.) does all the math giving out standard ICC, with CIE and HP/MS RGB compatible tables.

  2. But it is not necessary using the absolute CIE conformant measuring, when you are "calibrating" using non-standard luminant; basically using the "white" back-lightof your monitor as-is. In that case the calibrator will help you to get a uniform "gray" colour along the whole brightness range, and even correct the brigtness transfer function (gamma ramp) fo the monitor... Even with non standard liminant - it is just stretching and pushing RGB curves for keeping them in ballance according to sRGB, or "2.2". That is called calibration, because influences per channel one-dimensional transfer Keep in mind that monitor calibration ICC files are not the same as full color profiles. These contain the three "gamma ramp" one-dimensional vectors directly loaded into your graphics card.

(!!!)

  1. Now, (8) can be performed without the calibrator at all under premice that you know the R+G+B colour mixing capabilities of your display. Most displays (but not every) and not many TVs(related to the pixel structure, or to lossy signal encoding at high resolutions) have uniformly weighted colour mixing. Therefore you can synthesize any colour with a mix of pixels of fixed brightness, and compare it with the coloured pixel (a coloured rectangle) nearby on the same screen. One of the tools I know is CLTest, another is Pixperan, both discontinued. There are paid tools like Atrise Lutcurve and some rare others. This calibrates the display card LUT to monitor sRGB gamma curves only, and makes gradients uniform in color. The color tone is corrected by your own monitor controls manipulation. This method is HATED by most color maniacs and pro-photographers. The reason is that it gives pleasant brightness and grays reproduction, despite ignorance of many factors like black&white points and colour primaries(subpixel filters' natural colours). And since specialists can not apply all their vast knowledge about colour standards here, they will abuse you every time you mention tools like CLTest. Windows7-10 method is just a one step of the full process these programs perform.

  2. Another process is profiling. Since monitor color mixing can be a complex thing, and it is always very complex for printers, the calibration software builds large profiles of conformance of many possible color codes to the expected CIE values. Then the photo editing software may use a look-up table approach based on these profiles, for replacing every pixel with the color closely matching the CIE standard reproduction at the specific monitor/printer. Either calculated absolutley, or shifted basing on luminant and color width (gamut) perception. That is a resource-hungry per-pixel process not available in hardware on todays GPU boards. This is a necessary thing for any ink-jet printer (usually created at the factory for some average unit)

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