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``diff. of Gaussians'' -- difference of Gaussians

purpose:
Locate edges in a grayscale volume using the difference of Gaussians operator (an excellent approximation to the Laplacian of Gaussians operator) [20].

MORE CHECKING NEEDED HERE!

input:
An 8-bit volume.
output:
An 8-bit volume.
parameters:
Default parameters menu is
Detector width = 0
connectivity = 6
min dog value = 0
input from vol # = 0
copy output to vol # = 0
comments:

  1. It does not provide very meaningful results unless you use an operator having a detector width of at least 9 voxels (a number like 13 or so is preferable).
  2. It does not provide very meaningful results for small objects; e.g., objects that are <30 or so voxels in diameter.
  3. This is a fairly slow operation.



Updated: Fri May 19 14:39:07 CDT




Copyright 1994-99 Division of Physiologic Imaging, Dept. of Radiology, Univ. of Iowa


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