MED3x3 filter
The MED3x3 filter is a standard rank order filter which works in a 3 by 3 environment.
When 9 pixel values encountered in the input map are:
|
9 |
12 |
9 |
|
|
11 |
5 |
7 |
|
|
8 |
8 |
13 |
Then the median filter orders these 9 values as:
5, 7, 8, 8, 9, 9, 11, 12, 13
The value at rank order 5 is assigned to the pixel in the output map: 9.
Input pixel value 5 is smaller than the value of surrounding pixels in this example, while the output pixel value 9 is the median value of the 9 pixels examined.
See also: