Color image sharpening based on collective time-evolution of simultaneous nonlinear reaction-diffusion
Takahiro Saito, Jun Satsumabayashi, Hiroyuki Harada, Takashi Komatsu · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2003
Previously we have presented a method for selective sharpness enhancement of monochrome images. Our method is based on the simultaneous nonlinear reaction-diffusion time-evolution equipped with a nonlinear diffusion term, a reaction term and an overshooting term, and it can sharpen only degraded edges blurred by several causes without increasing the visibility of nuisance factors such as random noise. This paper extends our method to selective sharpening of color images. As to the how to extend it, we take into accounts some variations about the treatment of three color components and the selection of the color space. By experiments, we quantitatively evaluate performance of these variations. Among them, the collective treatment of color components based on the simultaneous full-nonlinear reaction-diffusion time-evolution achieves the best performance, and sharpens blurred color edges selectively much better than the existing sharpness enhancement methods such as the adaptive peaking method.