Method of and apparatus for image smoothing along a tangential direction of a contour

摘要

Smoothing in a tangential direction of a contour and detail enhancement in its perpendicular direction are simultaneously achieved with spatial filters having prescribed weighing factor distribution. An area including a contour is first designated, and a direction of the contour is detected. A weighted mean value of an image signal is computed with weighing factors distributed in the spatial filter. The weighing factors have an effect of smoothing in the tangential direction of the contour and an effect of detail enhancement in the perpendicular direction.