Beyond Grading - Blender Compositing and Post Processing - page 57

The Directional Blur node
The Directional Blur node can be used to create a fake motion blur effect by blurring
an image in a specified direction and magnitude. This can be used as a faster solu-
tion for Vector Blur, in specific cases. Since this is a fake blur, it blurs all points on
the image, without considering the movement of the points. Its parameters are as
follows:
• Iterations : This controls the number of times the image is duplicated to cre-
ate the blur effect. Higher values give smoother results.
• Wrap : This wraps the image on the x and y axis to fill in areas that become
transparent from the blur effect.
• Center : This sets the position for the blur center. It makes a difference if
Angle, Spin, and/or Zoom options are used.
• Distance : This regulates the largeness of the blur effect.
• Angle : This blurs the image at the angle specified from the center.
• Spin : This rotates the image at each iteration to create a spin effect from the
center point.
• Zoom : This scales the image at each iteration, creating the effect of a zoom.
The following screenshot illustrates the utilization of the Directional Blur node. It can
be observed that all the spheres are now blurred in a specified direction, unlike
in Vector Blur, where only the center sphere was in motion. In many rapid motion
scenes in which the scene subjects are far from the camera, this effect can give a
believable and faster result.