MMult

Function
The MMult function multiplies the color channels by the matte. This function is used to premultiply an image. When compositing with the Over node, Shake expects all images to be premultiplied. Premultiplication is usually automatic with 3D-rendered images, but not for scanned images. Also, use this to color correct a 3D-rendered image. Add an MDiv node to the image, perform your color corrections, and then add an MMult node into an Over operation.

Note: You can also choose to not insert a MMult node, and instead enable preMultiply in the Over node’s parameters.

For more information on premultiplication, see “About Premultiplication and Compositing”.

 

Parameters
Type
Defaults
Function
ignoreZero
int
0

Tells Shake to ignore pixels with an alpha value of 0.

0 = Multiplies entire image.
1 = Ignore zero-value pixels.

Synopsis

image MMult( image, int ignoreZero);

Script

image = MMult( image, ignoreZero);

Command Line

shake -mmult ignorezero

See Also
MDiv, IDiv, IMult