Importance of Luminance and Chrominance in Image Processing

    The human eye is more sensitive to the luminance(brightness) in an image as compared to the chrominance(color) information in an image. Thus, image recovery algorithms define a cost function in such a way that the regularization term applied to luminance component tries to preserve edges(high frequency information), while the regularization term applied to the chrominance component tries to ensure smoothness. The chrominance regularization thus removes color artifacts which are more sensitive and objectionable to the human eye.

(Source: S. Farsiu, D. Robinson, M. Elad, and P. Milanfar, “Advances and challenges in super-resolution,” International Journal of Imaging Systems and Technology 14, 47–57 (2004).)