This paper presents a new technique for segmenting images only on the basis of color information. It is shown how segmentation can bene t from splitting color signals into chromatic and achromatic channels and separately smoothing them through anisotropic di usion. Operatively, this is accomplished through two independent di usion rocesses: one involves only the chromatic information, conveniently embeddedin a complex function, while the other a ects the lightness information. The results of the two di usions are separately segmented by k-means clustering techniques and their combination yields the nal image partition into homogeneous regions. Some experimental results are reported in the paper which verify the e ectiveness of the proposed technique.