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8■n Chapter 1: Learning the Basics of Lip Sync
What this tells us is that G has few visual requirements, so it won’t be something we
build a specific shape for. Further, we just proved that any single pose we picked would
already be wrong two-thirds of the time, even in our small test. Given that, even if we did
want to build a G, how would we ever pick a single shape?
Both G sounds are created invisiblysolely using mechanisms inside the mouth, not
by the lips or even noticeable open/closed cues. This G example is here to begin to illus-
trate what is and, more importantly, what is not a viseme.
Starting with Whats Most Important: Visemes
For this noninclusive approach, where you’re trying to exclude extraneous mouth-to-
sound pairings, something youll need to know is what must be included. There are
certain sounds that we make that absolutely need to be represented visually, no matter
what. These are called visemes. Examples of visemes are Narrow for OO, as in food, and
Closed for M, as in mom. You just can’t make those sounds without those contortions.
Looking back, do you think G is a viseme? It isn’t. It couldn’t possibly be any less of a
viseme. It requires no contortion, and it did not suffer from any other contortions. It
is visually meaningless. There are going to be more visemes to address than the Open,
Closed, Wide, and Narrow variety I’ve touched on, but even this greater list of must-see
shapes can be “cheated” to fit into the simple circle-mouth setup you’ve seen and are
about to build.
Why Phonemes Aren’t Best for CGI
Phonemes work fantastically in classical animation, where nothing comes for free and
every frame has to be drawn. Used merely as a guide, with an animator drawing a new
picture for each frame, phonemes are great. In CGI, when you’re working with phonemes
as actual shapes, each a discreet pose in the rig, sync animation tends to end up overly
choppy, and counteranimation becomes too large a portion of the work. In other words,
when phonemes are an idea, they can and do work very well. When phonemes are unique
physical manifestations built deep into the core of a character rig, they can and often do
just get in the way of good sync.
Figure 1.3
All varieties of G
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