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``Average_Minimum'' -- average/minimum filter

purpose:
This filter first applies a window average and then a local minimum operation to an input volume. It reduces noise and makes a volume easier to segment. Use this filter when the regions of interest are dim (the filter favors dim regions). Also, see the function ``ave_max''.
input:
An 8-bit volume.
output:
An 8-bit volume.
parameters:
Default parameters menu is
x filter dim = 3
* y filter dim = 3
* z filter dim = 3
* no. of iterations = 1
* input from vol # = 0
* copy output to vol # = 0
*
The window average and local minimum operations use the same operator size.
comments:

  1. The filter is similar to a lowpass filter, yet the minimum operation makes it nonlinear. Use it to bring out dim regions.
  2. You can do a better version of this function by first doing a hamming lowpass filter (``lowpass'' in the ``enhance'' category) and then running a local minimum (``min'' in the ``morphology'' category).
  3. Moderate computation required.



Updated: Fri May 19 14:39:07 CDT




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