Apple Shake 4 - Manual (Page 85)

Chapter 1 An Overview of the Shake User Interface 85
Combining images with a DOD is an excellent way to optimize greenscreen or
bluescreen images that need to be cropped via a garbage matte anyway, because it
simultaneously removes the garbage areas and assigns an efficient DOD to the image.
The node tree above produces the folowing effect:
With a good understanding of the role of the DOD, you can optimize the tree before
and after the node in question. The above example not only optimizes any nodes you
attach to Inside1, but executes the Primatte and reads in the part of the image that is
inside of the DOD, reducing processing and I/O activity.
Keying, Color Correcting, and the Background Color
This section discusses the area outside of the DOD, which is called the Background
Color (BGColor).
Building QuickShape1
Primatte1 Inside1