Accuracy Improvement of Estimated Perceived Brightness Maps by Helmholtz-Kohlrausch Effect Using a Correction Coefficient. - Shinichi Hashimoto; Takaya Shizume; Hiroaki Takamatsu; Yoshifumi Shimodaira; Gosuke Ohashi (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2017)