Game Development Reference
Figure 4.16 The results of
changing the Blur Dimensions
value to Vertical.
not achieve this boxy result with other blur effects, although you
can alter the blur dimensions in other effects (Fig. 4.16).
The Channel Blur Effect
The Channel Blur effect is really useful, and for multiple pur-
poses. First, we'll examine how to use it creatively, then we'll use
it for a great utilitarian purpose.
Open the Channel Blur.aep project from the Chapter 4 folder.
We're going to start out in the Static Logo for AE comp. This comp
contains a logo I created in Adobe Illustrator. Apply the Channel
Blur effect to the Bkgrd layer. The isolated Bkgrd layer is seen in
Fig. 4.17 .
The Channel Blur effect is easy to understand, although its
practical uses may not be as readily apparent. This effect can
individually blur each channel—red, green, blue, and also the
alpha channel. Increase the Red Blurriness value, for example,
to blur only the red channel. This creates some interesting color
variations. In Fig. 4.18, I took the Red Blurriness value to 100.
This dissipates the red in the image, and seems to add green to
the result as more cyan is added on top of the yellow background.
Note that in this fi gure, all the logo elements have their visibility
turned back on, and the blur is only applied to the background
layer seen in Fig. 4.17 .
Likewise, having a Green Blurriness value of 100 blurs the
green, which in effect, adds magenta (Fig. 4.19).
One of the most unique aspects of this effect is that you can
also use it to blur the edges of a layer's alpha channel using the
Alpha Blurriness property. This creates a soft transparency around
You might have
noticed that even
though the red
in the background layer
was blurred, the red in the
text remained crisp. You
could blur it by applying
the Channel Blur effect
to the text layer. Or you
can create an adjustment
layer, then apply the
Channel Blur effect to the
adjustment layer. Then, all
the changes that you make
to the effect will adjust the
composite color and alpha
channels of the entire