Algorithm to desaturate RGB color-CodePudding

I have a question. Is there some way or some algorithm that I can use to desaturate an RGB value without converting the color to HSV or HSL? My RGB input is going to be fully saturated, therefore I just need a way to desaturate my color.

I'm working on a color picker and I need a fast and efficient way of doing this. Any suggestions would be much appreciated:)

CodePudding user response：

Simple approach (ignoring perceived lumunance like 0.3R 0.6G 0.11B and other formulas):

Initial color (r,g,b)
Gray color of the same intensity (i,i,i)
where i = (r g b) / 3

Deviations from gray components:

dr = i - r
dg = i - g
db = i - b

Let parameter t changes from 0 for initial saturated color to 1 for gray color. So

r' = r   dr * t  
g' = g   dg * t
b' = b   db * t