Apple Motion 4 - Manual (Page 962)

Circle Blur
Creates a circular blur within an image, specified by a center point that sets the center
of the blur effect, and a radius that sets the size of the affected region. The amount of
blur within the affected area can also be customized.
This filter is useful for quickly blurring a limited area within an image. For more
sophisticated control of the image region to be blurred, try the Compound Blur filter.
This filter causes rasterization in 3D groups.
Original image Center of Circle Blur on the right side of crab
Parameters in the Inspector
Center: Sets the position of the center of the blur effect.
Amount: Sets the amount of the blur.
Radius: Sets the radius of the circle defining the blurred area.
Crop: Sets whether or not the image is cropped beyond its original borders.
Mix: Sets the percentage at which the original image is blended with the blurred image.
HUD Controls
The HUD contains the following controls: Amount, Radius, and Crop.
Compound Blur
Blurs an object using the specified channel of a designated map image. You can use any
shape, still image, or movie file as the map image. You can select any or all of the red,
green, blue, alpha, or luminance channels to create the overall shape of the blur.
One of the fastest ways to use this filter is to create a shape object, and trace the subject
of the image you want to blur. Then, assign this shape as the Blur Map image, using either
its Luminance or Alpha channel to define the blurred area, and turn off the original shape
object in the Layers tab or Timeline to reveal the new blur effect.
When this filter is applied, Compound Blur uses the original image as the map to create
the initial blur. Drag any image into the Blur Map well to assign a different image.
962 Chapter 16 Using Filters