Introduction - If you have any usage issues, please Google them yourself
A bilateral filter is an edge-preserving smoothing filter. Whereas many filters are convolutions in the image domain, a bilateral filter also operates in the image s range—pixel values. Rather than simply replace a pixel s value with a weighted average of its neighbors, as for instance the Gaussian filter does, The bilateral filter replaces pixel s value by a weighted average of its neighbors in both space and intensity. This preserves sharp edges by systematically excluding pixels across the discontinuity from consideration.