Hue-preserving image enhancement via complementary enhancing terms

Abstract

Hue-preserving image enhancement is a very challenging and important research topic in image/video processing and computer vision fields. In the past decades, spectral methods, histogram-based methods, and spatial methods are proposed to partially tackle this problem. However, most of them still suffer from the challenges in enhancing color images while preventing hue shift. In this paper, we build two complementary terms in a variational framework for enhancing images: one is for increasing the image brightness, and the other is for strengthening the edge structure. The two enhancing terms are adaptively united to enhance color images and preserve the original hue simultaneously. The existence and uniqueness of minimizer for the proposed variational model are rigorously established. An efficient numerical implementation of our model is also accomplished via the popular split Bregman method. A number of numerical experiments and comparisons with some state-of-the-art methods are conducted to demonstrate the good performance of the newly proposed model.