The blur effect smoothes the image by blending adjacent pixels. This produces a smoother image and sometimes can be used to anti-aliase the image. For example texture flickering of insufficiently anti-aliased animations can be reduced this way.
The Blur effect can be controlled using the following settings:
Blur Level: Defines the amount of blur. Increasing the value makes images more blurred.
Width Channel: An optional channel for controlling blur size. For example, to obtain selective blurring, the user can add a channel property to part of scene objects and then apply blur to only those parts of the image where the channel values are set. The total blur size is computed as the following product:
blur size = Iterations * Blur Level * Blur Width channel
Geometric Weight: If set to one, blurring happens only across connected, continuous surface areas. Dislocated objects will not blur together. This is a useful option when anti-aliasing object specific channel information (such as ambient lighting) by averaging in post processing phase.
Normal: The channel, which defines surface normal continuity.
Distance: The channel, which defines distance continuity.