Abstract: In a method and apparatus for extreme-light image enhancement, an input image is passed to a lighting classification module in order to be classified into two categories: an under-exposed lighting condition and an over-exposed light condition. Then the classified image is subsequently passed to an enhancement module which comprises a first image enhancement unit and a second image enhancement unit using a mapping function based on a gamma mapping function for mapping the classified image to an output image, respectively. A parameter of the gamma mapping function is estimated by a parameter estimation network, based on the classified image. The parameter estimation network may be a lightweight CNN network which is trained by an unsupervised approach.