User guide

Viewing and Editing Images
12-35
• Median. Also useful for suppressing salt-and-pepper noise, this filter
calculates the median value of the pixels within the filtering window and
uses it to replace the value of the pixel being processed. The median filter
produces very little blurring if a small-sized window is selected.
• Maximum. This filter is useful for eliminating pepper noise in an image
(it worsens the effect of salt noise). It replaces the value of the pixel being
processed with the maximum value of the pixels within the filtering
window.
• Minimum. This filter replaces the value of the pixel being processed with
the minimum pixel value within the filtering window. This filter is useful
for eliminating salt noise in an image (it worsens the effect of pepper).
• MidValue. This filter is useful for suppressing uniform noise within an
image; however, it worsens the effect of pepper and salt. This filter
replaces the value of the pixel being processed with the mean of the
maximum and minimum pixel values within the filtering window.
• PowerMean. This filter is useful for suppressing salt and Gaussian noise
within an image (it worsens the effect of pepper noise). It replaces the
value of the pixel being processed with the power mean of the pixel
values within the filtering window.
• ContraMean. This filter is useful for suppressing pepper and Gaussian
noise within an image (it worsens the effect of salt). It replaces the value
of the pixel being processed with the contra-harmonic mean of the pixel
values within the filtering window.
• Adaptive. This filter is useful for suppressing Gaussian noise and salt
and/or pepper within an image. If your image contains a mix of salt and
pepper, select this filter.
To begin filtering, select a filter type from the pull-down list. A pop-up box
will ask you to select a filter size.