White balancing is performed using a mapping that maps the visible gamut's boundary into itself. A predefined color Win is mapped into a color Wout which is a white color or a color perceived as white under some viewing conditions. If Sin is some other color, a corresponding color Pin is determined on the visible gamut's boundary. Pin can be on the intersection of the visible gamut's boundary with a plane containing Sin and Win in a linear color coordinate system. Sin is mapped into a color Sout obtained from Wout and a value of the mapping on Pin.