Erode node — Natron 2.5.0 documentation

# Erode node

This documentation is for version 2.1 of Erode (net.sf.cimg.CImgErode).

## Description

Erode (or dilate) input stream by a rectangular structuring element of specified size and Neumann boundary conditions (pixels out of the image get the value of the nearest pixel).

A negative size will perform a dilation instead of an erosion.

Different sizes can be given for the x and y axis.

Uses the ‘erode’ and ‘dilate’ functions from the CImg library.

CImg is a free, open-source library distributed under the CeCILL-C (close to the GNU LGPL) or CeCILL (compatible with the GNU GPL) licenses. It can be used in commercial applications (see http://cimg.eu).

## Inputs

Input | Description | Optional
--- | --- | ---
Source |  | No
Mask |  | Yes

## Controls

Parameter / script name | Type | Default | Function
--- | --- | --- | ---
Size / `size` | Integer | x: 1 y: 1 | Width/height of the rectangular structuring element is 2*size+1, in pixel units (>=0).
Expand RoD / `expandRoD` | Boolean | On | Expand the source region of definition by 2*size pixels if size is negative
(Un)premult / `premult` | Boolean | Off | Divide the image by the alpha channel before processing, and re-multiply it afterwards. Use if the input images are premultiplied.
Invert Mask / `maskInvert` | Boolean | Off | When checked, the effect is fully applied where the mask is 0.
Mix / `mix` | Double | 1 | Mix factor between the original and the transformed image.