SmoothAnisotropic node


This documentation is for version 2.0 of SmoothAnisotropic.


Smooth/Denoise input stream using anisotropic PDE-based smoothing.

Uses the ‘blur_anisotropic’ 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
Amplitude / amplitude Double 60 Amplitude of the smoothing, in pixel units (>=0). This is the maximum length of streamlines used to smooth the data.
Sharpness / sharpness Double 0.7  
Anisotropy / anisotropy Double 0.3 Smoothing anisotropy (0<=a<=1)
Gradient Smoothness / alpha Double 0.6  
Tensor Smoothness / sigma Double 1.1 Geometry regularity, in pixels units (>=0)
Spatial Precision / dl Double 0.8 Spatial discretization, in pixel units (0<=dl<=1)
Angular Precision / da Double 30 Angular integration step, in degrees (0<=da<=90). If da=0, Iterated oriented Laplacians is used instead of LIC-based smoothing.
Value Precision / prec Double 2 Precision of the diffusion process (>0).
Interpolation / interpolation Choice Nearest-neighbor
Interpolation type
Nearest-neighbor: Nearest-neighbor.
Linear: Linear interpolation.
Runge-Kutta: Runge-Kutta interpolation.
Fast Approximation / is_fast_approximation Boolean On Tells if a fast approximation of the gaussian function is used or not
Iterations / iterations Integer 1 Number of iterations.
Set Thin Brush Defaults / thinBrush Button   Set the defaults to the value of the Thin Brush filter by PhotoComiX, as featured in the G’MIC Gimp plugin.
(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.