# Harmonic Mean Filter

## Command

Image

Filters

Harmonic Mean Filter

## Description

Applies a harmonic mean filter to an image.

In the harmonic mean method, the color value of each pixel is replaced with the harmonic mean of color values of the pixels in a surrounding region.

The harmonic mean is defined as:

A larger region (filter size) yields a stronger filter effect with the drawback of some blurring.

The harmonic mean filter is better at removing Gaussian type noise and preserving edge features than the arithmetic mean filter. The harmonic mean filter is very good at removing positive outliers.

## Dialog box

**Filter Size**: larger filter yields stronger effect.

Click Preview to judge the results.

Click OK to proceed.

## Examples

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