Morph targeting the mouth

Silva_Spoon

I am in the process of morph targeting a face for animation and have a few questions.

THe character has a mouth cavity and teeth. Should I make the teeth a seperate object?

if so how will they animate when the jaw opens since the morpher modifier will be on the lips and face but not on the teeth obj?

Should the jaw opening be a bone animation or should I not have a jaw bone and do jaw opening animations with a morph target?

How many morph targets do you guys do? So far I did: Mouth open/close, "Oooohhh" (pursed lip), smile left, smile right, frown left, frown right, sneer left, sneer right, eye brows down, eye brow up left, eyebrow up right, blink left, and blink right. Do you think these are suitable for facial animation. I know I can create a number of emotions with this set but do you feel I should create any more custom targets that I cant do by adjusting the sliders that I currently have?

SkullboX

I would never make the jaw open using morph targets, a bone will give you more accurate deformation for that (as it's a joint, not muscle/group of muscles like the lips) and much more control.

I personally use 2 joints for the jaw area. One to which the jaw bone is skinned to and one to which the lips are skinned to. This easily takes care of one of the most common mistakes in especially lipsync, which is that often the jaw opens and closes without the lips moving along with it. You could even consider adding a third bone, to which both the upper ald lower lips are skinned to, and link the bone for the lower lip to that. The bone for the jaw and the one for the lip(s) should both have the same parent.

Here is an example of an old, unfinisched lipsync that demonstrates this. If you look at for example the end of hello, you'll see that the 'llo' part is animated almost entirely done by doing nothing but making the jaw (without the lips) open. You'll see the opposite at '...men', where the jaw is already shut, and only the lips move.

As for the amount of morph targets, there really is no telling how much you're going to need. I guess it depends on the amount of detail and realism you'd want and how much the model allows in the first place. Apart from that, a large quantity of morphs will make the process of animating more tedious and you'll find that the degree the morphs make a difference in quality is mainly how well they blend with eachother instead of how the look in a static, extreme pose, so I'd say less is more - especially if you're doing this for game use.

In the end you'll most likely learn most by selecting some voice fragment, and make morphs along with creating a test animation. Good luck!