Smoothing

Anisotropic filters are a class of filter that reduces noise in an image while trying to preserve sharp edges

There are two implementations of Tschumperle/ R. Deriche filter ("anisotropic diffusion") for ImageJ Plugin

1. in the "imaging book" codes: see the javadoc here.

2. in Xlib

The Graph Cut plugin provides a way to obtain a globally smooth binary segmentation. As input, you have to provide a gray-scale image that represents the pixel affinities for belonging to the foreground. Via a single parameter you can adjust the smoothness of the segmentation.