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

VFX name:

i4D_Filter

IMPROMPTU Equivalent:

4D_Filtering

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 = mean
target_img = 4D_image_in
image_out = 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.