SmoothRollingGuidance node


This documentation is for version 2.0 of SmoothRollingGuidance (net.sf.cimg.CImgRollingGuidance).


Filter out details under a given scale using the Rolling Guidance filter.

Rolling Guidance is described fully in

Iterates the ‘blur_bilateral’ function from the CImg library.

CImg is a free, open-source library distributed under the CeCILL-C (close to the GNU LGPL) or CeCILL (compatible with the GNU GPL) licenses. It can be used in commercial applications (see


Input Description Optional
Source   No
Mask   Yes


Parameter / script name Type Default Function
Spatial Std Dev / sigma_s Double 10 Standard deviation of the spatial kernel, in pixel units (>=0). Details smaller than this size are filtered out.
Value Std Dev / sigma_r Double 0.1 Standard deviation of the range kernel, in intensity units (>=0). A reasonable value is 1/10 of the intensity range. In the context of denoising, Liu et al. (“Noise estimation from a single image”, CVPR2006) recommend a value of 1.95*sigma_n, where sigma_n is the local image noise.
Iterations / iterations Integer 4 Number of iterations of the rolling guidance filter. 1 corresponds to Gaussian smoothing. A reasonable value is 4.
(Un)premult / premult Boolean Off Divide the image by the alpha channel before processing, and re-multiply it afterwards. Use if the input images are premultiplied.
Invert Mask / maskInvert Boolean Off When checked, the effect is fully applied where the mask is 0.
Mix / mix Double 1 Mix factor between the original and the transformed image.