Apple Shake 4 - Manual (Page 458)

458 Chapter 16 Compositing With Layer Nodes
Parameters
This node displays the following control in the Parameters tab:
clipMode
Toggles between the foreground (0) or the background (1) image to set the output
resolution.
Common
The Common node compares two images and extracts or hides common elements. Use
Common to create difference mattes. The extracted elements are taken if the difference
between the two images is less than the set tolerances. A similar node is ISubA, which
subtracts two images and returns the absolute value of these images.
Parameters
This node displays the following controls in the Parameters tab:
clipMode
Toggles between the foreground (0) or the background (1) image to set the output
resolution.
mode
Tells Shake what to do with common elements.
• 0: “show” keeps common elements only, turning the rest black.
• 1: “hide” hides common elements, leaving different elements untouched.
• 2: “white” turns the image to black and white, keeping common elements white.
• 3: “black” is the inverse of “white.”
• 4: “proportion” takes the difference between the values, averages the values, and
then inverts the values.
rTol
The red color channel tolerance. If pixels between the two images are less than the
tolerance value, they are considered common.
gTol
The green color channel tolerance. If pixels between the two images are less than the
tolerance value, they are considered common.
bTol
The blue color channel tolerance. If pixels between the two images are less than the
tolerance value, they are considered common.
aTol
The alpha channel tolerance. If pixels between the two images are less than the
tolerance value, they are considered common.