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3.2.9 Automatic Kappa

<automatic_kappa></automatic_kappa>

  • on Default Setting
  • off

During the automatic noise computation process the images are smoothed using Perona-Malik anisotropic diffusion filtering. As previously explained, this algorithm requires a parameter "kappa" to automatically smooth homogeneous regions and strengthen edges.

This parameter, "automatic_B0_kappa", determines the kappa parameter in that process. If it is set to on, the program automatically determines a suitable kappa. This is the default value and is highly recommended.

If this is set to any other value, that value will be used for the "kappa" parameter. Reasonable values for this parameter are completely dependent on your data, and are generally determined using trial and error. A good starting value is ~40. If your images come out looking too smoothed (such that the center of mass of the image is not preserved) than use a lower number. If the images are not smoothed at all, then user a higher number. Note: We highly recommend using the default value for this tag.