Creating Motion Graphics with After Effects, 5th Edition

11 All About Track Mattes

Mastering track mattes is a prerequisite for creating complex multilayered compositions

We’ve been reinforcing the idea throughout this book that managing transparencies is the cornerstone of creating composite images. But not all images come with their own transparencies – or ones we necessarily want to use. Sometimes, we’d prefer to borrow another image to create those transparencies. This second image is called a matte.

A matte can be a grayscale still image, another movie, or an animated graphic such as text. At the end of the day, After Effects sees it as a collection of grayscale levels which it uses to define the transparency of another layer. Understanding matte logic and how to use mattes in a hierarchy of comps ...