Rank Filter

Creates a box of a user-defined size around each pixel, sorts all of the pixels in that box into a list in order of intensity, selects a pixel at a user-defined position in that list and replaces the initial pixel with that color. Useful for shrinking or growing images or masks, stripping out areas of extreme high or low intensity, and creating artistic effects. The Rank filter includes all of the functionality of the Median and Min Max Filters, and additionally allows other levels to be emphasized.

Requires an Input (Any).

Produces an Output (Any).

Filter

Width, Height	Sets the size of the box. Set a pixel values using the slider.
Tolerance	Protects areas where the change in intensity is small. If the minimum or maximum value determined within the box falls within the set Tolerance from the initial pixel value in any component, the pixel will not be replaced. Set a value between 0 and 1 using the slider.
Level	Sets the position or rank in the list of sorted pixels at which the pixel value will be selected. Set a value between 0 and 1 using the slider. A value of 0 will give the same effect as a minimum filter (erode), 0.5 produces a median filter, and 1.0 produces a maximum filter (dilate).
Search Mode	Sets the criteria on which the pixels are sorted. Select Red, Green, Blue, Alpha or Luminance.

Mask

Controls this operator's Mask Options.

Output

Controls this operator's Output Options.

Except where otherwise noted, this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License