Fan Zhang Yang Mo Yoo Yongmin Kim Lichen Zhang Liang Mong Koh Multiscale Nonlinear Diffusion and Shock Filter for Ultrasound Image Enhancement. 1972-1977 2006 conf/cvpr/2006 CVPR (2) http://doi.ieeecomputersociety.org/10.1109/CVPR.2006.203 db/conf/cvpr/cvpr2006-2.html#ZhangYKZK06