In this work we present a new algorithm for digital images unsupervised enhancement, called ACE for Automatic Color Equalization. It is based on a new computational approach that merges the “Gray World” and “White Patch” equalization mechanisms, while taking into account the spatial distribution of color information. Inspired by some adaptation mechanisms of the human visual system, ACE is able to adapt to widely varying lighting conditions, and to extract visual information from the environment efficaciously. ACE has shown promising results in solving the color constancy problem and performing an image dynamic data driven stretching. Tests and results are presented.