The facial expressions are one of the most important parts inside the animation of a character in 3D, we are certain that every work done in order to get the character’s animation is important, all the parts together make a good character animation, however, the facial expressions reflects the emotions of a person. By just looking at his face, or even just the eyes, you may know how he’s feeling. The body movements may help emphasizing the action, but it could be not necessary for understanding it.
It hasn’t been an easy task, due to the complexity that the characters got when they are interacting with others. Nowadays, characters made by computer are very often, they aren’t just in the animated movies; they also appear other sections as videogames, so making every part as detailed as possible is crucial, due to the viewers may notice the slightly change in the character’s face.
The facial expression has always been studied by the animators, so they could improve it later on, and the two areas that always take part are the physiology and phycology. But depending on what kind of animation we are making, the expressions will be different, some will be more realistic and others more exaggerated. In this dissertation will go through the different kinds of animation and how they use the facial expression. We will go through the cartoonish and the realistic character animation, as well as the common techniques used in order to achieve the expected result.
2 Facial animation techniques
First of all, for getting a good facial expression, we have to model the character’s face, and there are two ways of doing it, the ones which are based on geometric manipulations and the based on image manipulations. Every style has its subcategories, for instance, in geometric manipulation we can find key-framing, muscle based modeling, parameterization or interpolation, and others. And for image manipulations we find the morphing, texture manipulation, image blending and else. In this section we will see some of the techniques.
The interpolation is one of the common techniques inside the 3D facial modelling, although, it is usually made for achieving a simple expression. The technique is about using two key-frames, one the first frame and the other on the last one, or on the next ones. This way we will get a sensation of continuity and it will seem as the character is making an emotion. It is also known as linear interpolation, and the most intuitive technique when someone starts animating.
We model a closed mouth, with a sad shape, we...