Abstract: Ever since the advent of histogram equalization algorithms (“HE”) for image enhancements, there has been numerous variants of HE been proposed to improve or overcome the problems of the traditional HE. One of the drawbacks of the traditional HE is that the amount of enhancement is not adjustable. This invention gives a simple and efficient method to generalize the traditional HE to become a variable histogram equalization (“VHE”) by a single parameter, Q. Q ranges from 0 to 1 such that when Q equals 0, there is no enhancement and when Q reaches 1, the enhancement of VHE becomes the same as that of traditional HE. Therefore, the amount of image enhancement can be controlled by changing the parameter Q to achieve better visually appealing image enhancements.