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Erode (filter)

Filters input pixels relative to the size control, and is particularly useful with mattes. Negative values cause brighter areas to expand into darker areas and positive values cause darker areas to expand into lighter areas. Use the filter dropdown to control the erode computation speed (box) versus quality (gaussian).

Erode (filter) is similar to Erode (fast), but can be computationally more expensive because you can select the filter type to improve the erode quality.

Inputs and Controls

Connection Type	Connection Name	Function
Input	unnamed	The image or matte to erode.

Control (UI)	Knob (Scripting)	Default Value	Function
FilterErode Tab
channels	channels	none	The effect is only applied to these channels. If you set this to something other than all or none, you can use the checkboxes on the right to select individual channels.
size	size	1	Adjusts the size of pixels within the channel defined by the channels control. Values less than 1 increase the light pixels and vice versa.
filter	filter	box	Select the filter algorithm to use: • box • triangle • quadratic • gaussian NOTE: Box is the fastest to render, whereas Gaussian blur is the smoothest.
mask	N/A	disabled	Enables the associated mask channel to the right. Disabling this checkbox is the same as setting the channel to none.
mask	maskChannelInput	none	The channel to use as a mask. By default, the effect is limited to the non-black areas of this channel.
inject	inject	disabled	Copies the mask input to the predefined mask.a channel. Injecting the mask allows you to use the same mask further downstream.
invert	invert_mask	disabled	Inverts the use of the mask channel, so that the effect is limited to the non-white areas of the mask.
fringe	fringe	disabled	Blurs the edges of the mask.
mix	mix	1	Dissolves between the original image at 0 and the full effect at 1.