SmoothType Fields

(bilateral filter) - applying bilateral 3x3 filtering with color sigma=param1 and space sigma=param2. Information about bilateral filtering can be found

(simple blur) - summation over a pixel param1 x param2 neighborhood with subsequent scaling by 1/(param1 x param2).

(simple blur with no scaling) - summation over a pixel param1 x param2 neighborhood. If the neighborhood size may vary, one may precompute integral image with cvIntegral function

(Gaussian blur) - convolving image with param1 x param2 Gaussian kernel.

(median blur) - finding median of param1 x param1 neighborhood (i.e. the neighborhood is square).