Goal of the softwares GammaAdjuster (GA) and Output Linearization (OL)

The goal of both software tools is the equally spaced visual display output for equally spaced rgb* data in the file according to IEC 61966-2-1 (sRGB colour space). For applications the ergonomic standard ISO 9241-306:2018 defines 9 step achromatic and chromatic colour scales, download ISO-test charts AE49 of

https://standards.iso.org/iso/9241/306/ed-2/index.html

The output quality is specified by the regularity index g* according to ISO/IEC 15775:2022, download the ISO-test charts https://standards.iso.org/iso-iec/15775/ed-2/en

The regularity index g* depends on colour differences DE*ab in the colour space CIELAB. It is valid g*=100 (DE*min / DE*max). If the eight colour differences DE*ab of the nine step series are equal, then g*=100. If two steps are not distinguishable, then g*=0.

The visual output spacing is mainly changed by the display reflection of the ambient light. This change is known as gamma change and is described by a power function.

Software GammaAdjuster (GA, rgb*-colour management for the consumer area)

The software GammaAdjuster is a useful tool for changing the gamma value of the whole display output. A special Gamma value is determined, which produces approximately an equally spaced visual display output. The change is possible for three rgb* values together or individually for r*, g*, and b*.

The original gamma value is automatically restored by macOS when you exit the software.

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Remark: The software GA corrects the values 0 <= rgb*=w* <= 1 by a power function, for example by w=w*0,5, if the too dark actual output has been produced by the inverse function w=w*2.

Software Output Linearization (OL, rgb *-color management for the professional area)

The software Output Linearization is a useful tool for producing the visual output of many 9 step colour series  of a test file. The software OL may produce one individual function w=f(w*) for the achromatic series Black N - White W. In many cases this individual function produces also an approximately equally spaced display output for 12 other chromatic series.

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Colour series N-W, N-RGBCMY, and RGBCMY-W and different viewing parameters. 
The individual function of any series depends on many viewing parameters, for example adaptation luminance, and adjacent or separated samples.

Remark: For professional and research applications of rgb* colour management, see for example a paper of K. Richter (2025, 2,6 MB, 23 pages)
https://color.li.tu-berlin.de/tubws25e.pdf