Vibrance: Adjusts the saturation so that clipping is minimized as colors approach full saturation. This setting changes the saturation of all lower-saturated colors with less effect on the higher-saturated colors. Vibrance also prevents skin tones from becoming oversaturated.
From the code in PhotoDemon, it is the adjustment of the saturation of the HSL curve.The curve of krita is a mixture of hsv and lab. Its effect is a bit far from each other. It is mainly the determination of “low saturation”.
So we use gmic’s “curve”. It has several models, we choose hsl. from -100 to 100 is roughly moving the point from (192, 95) to (62, 160).Of course, you can also move it more freely
