Abstract: Enhancement algorithm of images based on Retinex theory is proposed.The essence of Retinex theory is to gain the reflection property R from image I,i.e.,to gain the original image of an object without the properties of incident lignt.To improve multi-scale Retinex algorithm is to use histogram equalization algorithm in multi-scale Retinex algorithm.Images gained by that method have lifelike colors and large dynamic range.Experiments show that the algorithm has enhancing effect on color images.

Key words: image enhancement, Retinex theory, color constancy, multi-scale, histogram equalization, dynamic compression range