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``nonmax suppression'' - non-maximum suppression

VFX name:
iNonmaxSuppress
IMPROMPTU Equivalent:
Nonmaxima_Suppression
purpose:
Zero out a voxel if it is not a local maximum in some sense.

For ``connectivity = 6'', a voxel will not be set to 0 if it is a local maximum in either the x , y, or z directions. For ``connectivity = 26'', the voxel must be a local maximum within its local 3x3x3 neighborhood.

The operation is typically used in conjunction with edges detection. For example, a typical edge-detection sequence is

1.
Calculate edge strengths using the ``Kirsch edge operator'', zeroing out voxels having low-valued edge strengths.
2.
Apply a 6-connected ``non-maxima suppression'' to the volume.
The result is a grayscale volume containing a thinned-down set of edges.
input:
An 8-bit volume.
output:
An 8-bit volume.
parameters:
Default parameters menu is
connectivity = 6
comments:
See below.
1.
This operation takes a little more computation than a typical 3x3x3 local maximum (``max'').



MultiDimensional Image Processing Lab, Penn State University