Methods and apparatuses are disclosed for assessing pigmentation of skin based on images thereof. In disclosed implementations, a cross-polarized blue image of skin is obtained and processed to extract pigment distribution information. Useful applications include assessing depigmentation, as in the skin condition vitiligo, as well as assessing re-pigmentation such as due to treatment. In addition to the spatial extent of depigmentation, implementations of the present disclosure can also provide the degree of depigmentation. The degree and area of depigmentation can be measured with better accuracy and sensitivity than known techniques.
