This software implements a method for smoothing 2D and 3D objects in binary images while preserving topology. Here, objects are defined as sets of grid points, and topology preservation is ensured by the exclusive use of homotopic transformations defined in the framework of digital topology. Smoothness is obtained by the use of morphological openings and closings by metric discs or balls of increasing radius, in the manner of alternating sequential filters from the field of mathematical morphology.