How to get rgb value by cimg?

Question

CImg src(\"image.jpg\");
int width = src.width();
int height = src.height();
unsigned char* ptr = src.data(10,10); 

How can I

Answer 1

@wamp: I don't know about CImg but grayscale images in RGB have:

R = G = B

and in CMYK:

C = M = Y = 0

K = luminance

So you don't even need a function for that...