Fast Fourier transform-based Retinex and alpha-rooting color image enhancement
Artyom M. Grigoryan, Sos С. Agaian, Analysa M. Gonzales · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2015
Efficiency in terms of both accuracy and speed is highly important in any system, especially when it comes to image processing. The purpose of this paper is to improve an existing implementation of multi-scale retinex (MSR) by utilizing the fast Fourier transforms (FFT) within the illumination estimation step of the algorithm to improve the speed at which Gaussian blurring filters were applied to the original input image. In addition, alpha-rooting can be used as a separate technique to achieve a sharper image in order to fuse its results with those of the retinex algorithm for the sake of achieving the best image possible as shown by the values of the considered color image enhancement measure (EMEC).