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3.2.5 Smoothing Algorithm

<smoothing_algorithm></smoothing_algorithm>

  • gaussian
  • PM
  • area
  • rician

This setting is ONLY active when the "smoothing" setting is turned on. Otherwise, it does not have any effect on the algorithm.

If the "smoothing" option is turned on, the user is able to choose from a couple of options.

  1. Gaussian: When this option is chosen, all images are smoothed with a Gaussian kernel. Please note that this option will blur edges and might destroy some image structures.
  2. PM: Perona-Malik Anisotropic gradient based filtering (edge favoring). This smoothing algorithm smoothes the image on regions where the image gradient is low (non-edge regions) and enhances the regions with high gradients (edge regions).1
  3. area: Perona-Malik Anisotropic gradient based filtering (area favoring). This algorithm is similar to PM but it favors homogeneous regions instead of edges.
  4. rician: Anisotropic filtering with Rician noise bias corrector. THIS OPTION IS NOT TESTED YET and MAY CAUSE THE PROGRAM TO CRASH.

References

  1. P. Perona, J. Malik, Scale-space and edge detection using anisotropic diffusion, (1990) PAMI 12(7), pp. 629-639. Abstract