How to find pixel value of different face skin colors?

Hi, i am quite new to image processing. I would like to know how can i detect area of different skin colours. For example, causcassion, asian, etc

Answer 1

[Image Analyst]

First get a mask of the face - a binary image that's true where there is face and false elsewhere. Then...

% Extract the individual red, green, and blue color channels using imsplit() (introduced in R2018b).
[redChannel, greenChannel, blueChannel] = imsplit(rgbImage);
meanR = redChannel(faceMask)
meanG = greenChannel(faceMask)
meanB = blueChannel(faceMask)