Pa r t I we start animating, building, or rigging anything, let’s be sure we’re speak- RI Before AL Getting to Know the Face TE ing the same language. In Chapter 1, I talk about talking, pointing out the things that are MA important in speech visually and isolating the things that are not. Narrowing our focus to lip sync gives a good base from which to build the more complicated aspects of the work D later. In Chapter 2, I define and outline, in the same focused way, the top half of the face.
Chapter 1 Learning the Basics of Lip Sync In modeling for facial animation, mix and match is the name of the game. Instead of building individual specialized shapes for every phoneme and expression, like for an F or a T, we’ll build shapes that are broader in their application, like wide or narrow, and use combinations of them to create all those other specialized shapes. On the animation front, it’s all about efficiency.
■ Chapter 1: Learning the Basics of Lip Sync The Essentials of Lip Sync Figure 1.1 A human mouth in the four basic poses People overcomplicate things. It’s easy to assume that anything that looks good must also be complex. In the world of 3D animation, where programs are packed with mile after mile of options, tools, and dialog boxes, overcomplication can be an especially easy trap to fall into.
The Essentials of Lip Sync At its core, that’s really all that speech entails. When lip-syncing a character with a plain circle for a mouth (which we’ll do in just a minute), the shapes in Figure 1.2 are all that’s needed to create the illusion of speech. Your reaction to this very short list of two motions might be, “What about poses like F where I bite my lip, or L where I roll up my tongue?” Ignoring that kind of specificity is precisely the point right now.
■ Chapter 1: Learning the Basics of Lip Sync the pursing of your lips for P is different than for B; how your tongue starts its way to the roof of your mouth early in the B sound and stays there until just a split second after the end of the word. You’d think that all these details give you a better idea of how to re-create the word pebble in animation, right? Wrong! Most often, that would be exactly the wrong way to do it.
Speech Cycles shape, but as the sum of its critical components. To start, let’s talk about the two major speech cycles. In its simplest form, there are two distinct and separate cycles in basic sync: open and closed, as in jaw movement, and narrow and wide, as in lip movement. When I use the word cycle, I’m merely referring to how the mouth will go from one shape to the other and then back again. There are no other shapes along the way.
■ Chapter 1: Learning the Basics of Lip Sync Figure 1.3 All varieties of G 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.
Starting with What’s Most Important: Visemes In the search for a better system for CGI sync, something became very apparent: There are three different kinds of sounds you can make during speech, and not all of them are easy to see! You’ve got lips, a tongue, and a throat. Phoneme-based systems lump all of these sounds together, and that is where the problems start. The only sounds you absolutely have to worry about are the sounds made primarily with the lips.
■ Chapter 1: Learning the Basics of Lip Sync Open Mouth Sounds Table 1.2 Example open mouth sounds Many sounds have no real shape to them, so they’re out as visemes. Another group of sounds have no shape in the sense that the lips aren’t contorting in a particular way, but they have the common characteristic that the mouth must be open. These sounds are listed in Table 1.2. I don’t consider these visemes but instead refer to them as open or jaw sounds.
Starting with What’s Most Important: Visemes ■ 11 Visemes Aren’t Tied to Individual Sounds One viseme shape can represent several sounds as read. For example, you might not read the AW in spa and draw as the same letters, but you can represent them with the same visual components. This is going to give you fewer things to animate and keep track of, leaving you more time to be a performer. Visemes have certain rules that must be followed.
■ Chapter 1: Learning the Basics of Lip Sync Most of these are what I’ll call “absolute” shapes: EEs are wide, but they don’t necessarily need to be the widest shape ever—they just need to be identified as being wide. Same with OOs or OHs. They don’t need to be the narrowest, just easily identifiable as a narrow pose. That’s how the system works.
Starting with What’s Most Important: Visemes The term rest in the following chart refers to the width of the mouth as it is at rest, in the default position, but it does not necessarily mean Closed. Another way to describe rest would be to say it is neither particularly Wide nor Narrow.
■ Chapter 1: Learning the Basics of Lip Sync is called (not surprisingly) opposites, and it’s explained in Chapter 4. Opposites is an idea not unlike anticipation. what This has two shapes. With the w portion of the word, we need an OO shape—it’s a viseme. With the ut portion of the word, UH-T, we’ve hit T. Like R, the T is relative. We widen the mouth on this sound to show that another viseme besides UH is present. This shape doesn’t need to be anything specific; it’s just wider than UH.
The Simplest Lip Sync Hmm, that’s interesting. It looks like we’re seeing the same motion over and over. This is a bit of an oversimplification because of timing and strength of the motions, but in essence, the Open/Closed cycle is going to be a function of syllables. The Open/Closed should be treated like a sock puppet. If all we had as a tool to work with was Open/ Closed, we should still be able to convince people that the words are coming out of the character’s mouth.
■ Chapter 1: Learning the Basics of Lip Sync 6. Select one of the duplicates and name it OpenClosed. In component mode, reshape it to look like an open mouth. 7. Select the other duplicate and name it WideNarrow. In component mode, reshape it to be wider. Be sure to include all the points in the widening, not just the end ones. 8. Now that you have your shapes, select the two duplicates and then Shift+select Mouth last.
The Simplest Lip Sync 5. Check all the boxes and fill them in as shown in the screen shot, limiting the motion in X from –1 to 1, in Y from –1 to 0, and in Z from 0 to 0. 6. Move locator1 out of the way of the mouth. MouthControl, being the child, should follow. (As I’m sure you’ve guessed, MouthControl will be how we manipulate the shapes on Mouth.) 7. Select Mouth, and then in the Channel Box under Inputs, highlight MouthShapes. 8. Go to Window ➔ Animation Editors ➔ Expression Editor. 9.
■ Chapter 1: Learning the Basics of Lip Sync Using the Sync Tool In this Maya scene, we’re going to continue using the slider, the shapes that slider controls, and what we’ve learned about syncing by viseme to take all of it for a test run. Let’s do a silent practice word, why, which is one of the easiest for this particular rig. If you’re finding that the frame numbers aren’t lining up for you, give your preferences a look and make sure they’re at 24 fps; film.
The Simplest Lip Sync concepts of both shapes and controls before we get too crazy. With some patience, I think you’ll amaze yourself with your work in a surprisingly short time. On the book’s website, there’s some sound for you to play with. Files for each of the examples we’ve already walked through are in the Chapter 1 folder, named sentenceName.wav. (If you need help loading sounds into your software, please see Chapter 4.
