Introduction - Computer Animation: Algorithms and Techniques - page 9

Willis O'Brien of King Kong fame is generally considered the dean of this type of stop-motion ani-
mation. His understudy, who went on to create an impressive body of work in his own right, was Ray
Harryhausen ( Mighty Joe Young , Jason and the Argonauts , and many more). More recent impressive
examples of three-dimensional stop-motion animation are Nick Park's Wallace and Gromit series and
Chicken Run and Tim Burton's projects such as The Nightmare Before Christmas , James and the Giant
Peach , Corpse Bride , and Alice in Wonderland .
Because of computer animation's close association with video technology, it has also been
associated with video art, which depends largely on the analog manipulation of the video signal in
producing effects such as colorization and warping [ 12 ]. Because creating video art is inherently a
two-dimensional process, the relationship is viewed mainly in the context of computer animation
post-production techniques. Even this connection has faded because the popularity of recording
computer animation by digital means has eliminated most analog processing.

1.3 Animation production
Although producing a final animated film is not the subject of this topic, the production process merits
some discussion in order to establish the context in which an animator works. It is useful for technical
animators to have some familiarity with how a piece of animation is broken into parts and how a fin-
ished piece is produced. Much of this is taken directly from conventional animation and is directly
applicable to any type of animation.
A piece of animation is usually discussed using a four-level hierarchy, although the specific naming
convention for the levels may vary. 6 Here, the overall animation—the entire project—is referred to as
the production. Typically, productions are broken into major parts referred to as sequences . A sequence
is a major episode and is usually identified by an associated staging area; a production usually consists
of one to a dozen sequences. A sequence is broken down into one or more shots ; each shot is the record-
ing of the action from a single point of view. A shot is broken down into the individual frames of film.
A frame is a single recorded image. This results in the hierarchy shown in Figure 1.4 .
Several steps are required to successfully plan and carry out the production of a piece of animation
[ 23 ][ 44 ] . Animation is a trial-and-error process that involves feedback from one step to previous steps

Production

Sequence 1
shot 1

Sequence 2

shot 2 shot 1 shot 2 shot 3 shot 4

Frame 1 Frame 2 … Frame n

FIGURE 1.4
Sample hierarchy of a simple animation production.

6 Live-action film tends to use a five-level hierarchy: film, sequence, scene, shot, and frame [ 9 ]. Here, the terminology, which
is often used in feature-length computer animation, is presented.