Next: ``Average_Minimum'' -- average/minimum
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- purpose:
- This filter first applies a window average
and then a local maximum operation to an input volume. It reduces
noise and makes a volume easier to segment. Use this filter when
the regions of interest are bright (the filter favors bright
regions).
- 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 maximum operations use the same
operator size.
- comments:
-
- The filter is similar to a lowpass filter, yet the
maximum operation makes it nonlinear. Use it to bring out
bright regions.
- 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 maximum (``max'' in the ``morphology'' category).
- Moderate computation required.
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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