Picture editing by simultaneously smoothing figure protrusions and dents

A smoothing method based on the simultaneous processing of the distance transforms of the figure and of its complement is described. This method can be regarded as a tool to enrich the set of the picture modifications that are achievable by using distance transformations. Both figure protrusions and dents are modified within the same process in a parallel fashion. In the standard method based on the application of a suitable sequence of shrink and expand operations, figure protrusions and dents are modified within two distinct processes. Thus, the proposed method is computationally more convenient than the sequence of the two previous processes