9. Pre- or postmultiplication of a matrix A by a scalar matrix multiplies all entries of A by the constant entry in the scalar matrix. It is equivalent to scalar multiplication of the matrix, by that scalar appearing on the diagonal.

What is Premult and Unpremult in nuke?

By Pluralsight on November 30, 2014

Premult and Unpremult in NUKE are nodes that can sometimes be overlooked. This is because the effects of using them or the lack of using them may not seem to be too apparent until you get up close or make drastic changes.

What is a Premult in nuke?

The simple definition of premult is to multiply the alpha and the RGB of the input together. Therefore if you multiply anything by 0, you will receive a value of 0 and that area will remain black. ... But if you multiply it by 1, the area will keep the original RGB since any number multiplied by 1 stays the same.