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``4D_Filtering'' -- 4D mean filter and grayscale inversion

purpose:
Performs 4D filtering on 4D volume sequences stored in ANALYZE format. Mean filtering or grayscale inversion can be selected.

For mean filtering, an 8-connected structuring element is used. Edges are handled in the following manner: At the first and last time-points, 3D (xyz) processing is used. At the first and last slices of each time-point, 3D (xyt) processing is used. At the first and last slices of the first and last time-points, 2D (xy) processing is used.

For grayscale inversion, each hypervoxel of the output image is set to the grayscale value 255 minus the input hypervoxel's grayscale value.

input:
An 8-bit 4D volume sequence, read from disk.
output:
An 8-bit 4D volume sequence, written to disk.
parameters:
Default menu parameters are
Method of 4D filtering = mean
input filename = 4D_image_in
output filename = 4D_image_out
``Method of 4D filtering'' can be set to either ``mean'' or ``grayscale inversion.'' The filenames of the 4D input and output images should be entered in the appropriate slots.
comments:

  1. ``Mean'' performs quick and easy 4D low-pass filtering.
  2. Moderate computation time required.



Updated: Fri May 19 14:39:07 CDT




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