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Blur

Adds blur to an image or matte using box, triangle, quadratic, or gaussian filter algorithms. The blur value is calculated for image pixels by examining their neighbors within the constraints of the size control (in pixels), and applying the selected algorithms. The default, gaussian, produces the smoothest blur, but takes longer to render.

You can also create this node by pressing B on the Node Graph.

Inputs and Controls

Connection Type	Connection Name	Function
Input	unnamed	The image sequence to blur.
mask	An optional image to use as a mask. By default, the blur effect is limited to the non-black areas of the mask. At first, the mask input appears as triangle on the right side of the node, but when you drag it, it turns into an arrow labeled mask. If you cannot see the mask input, ensure that the mask control is disabled or set to none.

Connection Type

Connection Name

Function

Input

unnamed

The image sequence to blur.

mask

An optional image to use as a mask. By default, the blur effect is limited to the non-black areas of the mask.

At first, the mask input appears as triangle on the right side of the node, but when you drag it, it turns into an arrow labeled mask. If you cannot see the mask input, ensure that the mask control is disabled or set to none.

Control (UI)	Knob (Scripting)	Default Value	Function
Blur Tab
channels	channels	all	The blur 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	0	Sets the radius within which pixels are compared to calculate the blur. Higher values widen the compare area, producing more blur.
filter	filter	gaussian	Select the filter algorithm to use: • box • triangle • quadratic • gaussian NOTE: Box blur is the fastest to render, whereas Gaussian blur is the smoothest.
quality	quality	15	Controls the trade off between faster processing time at lower values, and smoothness at higher values. The image is scaled down so the blur filter is no larger than this number, and then scaled up with linear interpolation after filtering.
crop to format	crop	enabled	When enabled, the bounding box cannot grow past its incoming size. This avoids creating oversized bounding boxes that can take longer to compute.
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 filter 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 filter 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 blur effect at 1.