Common
Function
This function compares two images and extracts or hides common elements. Use
this to do Difference mattes. The extracted elements are taken if the difference
between the two images is less than the Tolerances you set. A similar function
is ISubA, which will subtract
two images and return the absolute value of these images.
Parameters
|
Type
|
Defaults
|
Function
|
clipMode |
int
|
0 | Toggles between foreground (0) and background resolution (1) |
mode |
int
0 - 5 |
0 |
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" turn 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 them, and then inverts it. |
Tol |
float
|
0, rTol, rTol, rTol |
The Tolerance values. If pixels between the two images are less than the Tolerance value, they are considered common. |
Synopsis
image Common( image Foreground, image Background, int clipMode, int mode, float redTol, float greenTol, float blueTol, float alphaTol );
Script
image = Common( Foreground, Background, clipMode, mode, redTol, greenTol, blueTol, alphaTol );
Command Line
shake -common image clipMode "mode" redTol etc...
Example
shake lisa.iff -solarize .5 -common lisa.iff 1 4 .1
shake lisa.iff -mmult -common lisa.iff 1 2