Previsualization is used as a planning tool, as seen here in the previs (left) and the finished images from Panic Room. All Panic Room images © Columbia Pictures. Courtesy of Softimage|XSI.

Keyframe helped X-Men save on time and money with previs. © 20th Century Fox. All rights reserved. Courtesy of Keyframe Digital Prods. Inc.

You hear a lot about previsualization these days; it’s also called “previs” or “previz.” There are even highly visible specialists in the field, called “previsualization supervisors,” a job category that did not even exist a few years ago. What exactly is previs, and how does it relate to animation and gaming?

What it is?
A little history is in order to illustrate the basic functions of previs. Long ago (and far away), classic animation started the formal process that led to previs, because animation directors, unlike their live film counterparts, did not have actors that could “walk through” a scene to try different ideas before shooting began. Perhaps the first rudiments of it were the “story scripts” generated for Steamboat Willie, which combined key staging sketches with detailed typewritten instructions. These were the predecessors to the storyboard, which Walt Disney developed for planning all of his animated films; they quickly became a standard tool for live-action features as well.

With the dawn of digital animation and gaming came animatics. These are not to be confused with “rough draft” post-production VFX scenes — by the time these are generated, the film is typically in the can. “Modern previsualization is a planning tool for the film itself, before a particular sequence is shot,” says Ron Frankel, a previsualization supervisor on major films such as Panic Room and Minority Report. “It starts out with 3D storyboards, which are then animated. The sets created in previs are very exact replicas of the film production environment, including the limits of the stage, used to help the director design the film and tell the story in a particular way. After the sets are built, rough computer versions of the actors are created and inserted into the scenes.”