CE VS - Contrast Enhancement - Variance smoothing

(9/30/04)

PURPOSE

Creates variance smoothed image/volume. May be useful for removing outlying values. Works on images and volumes.   Example.

SEE ALSO

CE VAR [Contrast Enhancement - Variance]

USAGE

.OPERATION: CE VS
  <or> CE VS [npix]

.INPUT FILE: VOL001
[Enter the name of the input file.]

.OUTPUT FILE: VOL002
[Enter name for output file.]

.NEIGHBORHOOD X, Y, & Z: 3 3 3
[Length of the neighborhood around a pixel. Must be odd numbers.]

NOTES

  1. Image/volume is "circularly closed" so that pixels on boundaries have a neighbor on opposite boundary.

  2. 'Variance' is (1/N-1) * summation (over the neighborhood) of the square of the difference between the pixel's intensity and the average intensity of pixels in the neighborhood. (Where N is the number of pixels in the the neighborhood.) When the difference between the pixel intensity and the local variance is greater than the local variance and the local variance is greater than the image variance the pixel intensity is set to the local median.

  3. Optional output register (if given on operation line) will receive number of altered pixels/voxels.

SUBROUTINES

FILTER

CALLER

UTIL2

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