Smoothing vs. sharpening of color images: Together or separated

[EN] It is still a challenge to improve the efficiency and effectiveness of image denoising and enhancement methods. There exists denoising and enhancement methods that are able to improve visual quality of images. This is usually obtained by removing noise while sharpening details and improving edges contrast. Smoothing refers to the case of denoising when noise follows a Gaussian distribution. Both operations, smoothing noise and sharpening, have an opposite nature. Therefore, there are few approaches that simultaneously respond to both goals. We will review these methods and we will also provide a detailed study of the state-of-the-art methods that attack both problems in colour images, separatelyThe second author acknowledges the support of grant MTM2015-64373-P (MINECO/FEDER, UE) and the third author acknowledges the support of grant TEC2016-79884-C2-2-R (MICINN/FEDER).Pérez-Benito, C.; Morillas, S.; Jordan-Lluch, C.; Conejero, JA. (2017). Smoothing vs. sharpening of color images: Together or separated. Applied Mathematics and Nonlinear Sciences. 2(1):299-316. doi:10.21042/AMNS.2017.1.00025S2993162