Research Of Virtual Eye Model & Eye Movements And Expressions

As the leading role of the real world, human is also the active agent in the virtual world. Due to the rapid development of computer vision (CV) and virtual reality (VR), virtual face design has been receiving significant attention lately. People's eyes can be windows into their hearts. The realism and emotion representation ability of eye model directly influence the results of facial model and facial animation. As a result, it is significative for both theory research and potential application to study virtual eye modeling as well as the representation and animation of eye movements and expressions.Four aspects are described in this dissertation:1. A 3D muscle controlled eye (3D-MCE) model is presented. Based on anatomy theory and motoric characteristics, 3D-MCE model consists of two parts: the internal part which is constructed as rigid body of eyeball, and the external part which is constructed as flexible body of eyelids, eyebrow, forehead and nose, etc. This method improves the flexibility and realism of eye model when the data quantity is small.2. A 3D muscle control method is presented. According to the principle of volume invariance in deformation, this method adds cross-wise direction movement to the length-wise direction movement which is defined by Waters' muscle model. So the displacement of feature points caused by muscle contraction can be divided into three orthogonal component motions. This method can be applied to 3D-MCE model, and be used to control eye movements and expressions.3. A method called multi-curve spectrum to represent and animate eye movements and expressions is described. This method describes and animates eye movements and expressions with a group of time-varying curves of normalized muscle contraction. A method of capturing multi-curve spectrum from single video is presented.4. The relationship among 3D-MCE model, multi-curve spectrum and MPEG-4 standard facial model is studied. Based on the correspondences between 3D-MCE (3D Muscle Controlled Eye) model and MPEG-4 in feature points, animation parameters of eye movements and expressions, coordinates and scales, a method of two-way data transformation between MPEG-4 standard video stream and multi-spectrum is presented.The above-mentioned methods have been testified by sets of experiments. The experiment results show small data quantity, low computing complexity, low computing time, realistic eye model and vivid eye movements and expressions. Compared with single mesh model, 3D-MCE model has the advantage of good fidelity and enhanced flexibility. Multi-curve spectrum is simple, universal and easy to apply.The primary contents of this thesis are eye modeling, representation and animation. The methods mentioned above can also be used to facial modeling and animation.