将机械工程中的有限元方法用于人脸的三维建模,利用人脸上提取的99个特征点和一些辅助点,用光滑的样条曲线模拟人脸表情肌分布位置连结成线,由线生成三角面片和四角面片组合的有限元建立的人脸几何模型。给该模型定义合适的单元类型、实常数等参数,定义能与人脸皮肤等效的材料属性,并在眼睛、嘴等动作敏感位置加一定量载荷求解,模拟人脸表情动作。从求解的应力图中可以看出,该几何模型变形均与人脸表情动作时皮肤弹性变形一致。该方法可以快速、准确的进行三维人脸参数化建模,可方便提取特征点进行人脸识别。这种建模方法为人脸三维建模提供了一种新的思路和可靠的理论依据,同时降低了后期人脸识别的难度。
Finite element method applied in mechanical engineering is adopted to construct 3D facial model. Firstly, simulated facial expression muscle distribution, 99 key points is which are extracted from face and some auxiliary points composed lines by smooth spline curve. Secondly, the geometry model is then produced by triangle curved surfaces and quadrilateral ones being composed of the former lines. After that, 3D facial model is given some parameters such as suitable element type, constant and equivalent skin material attribute, and then is applied the load on eyes, mouth, etc to simulate the expression action of personal face. It is shown from the result of stress diagram that the deformation of facial geometry model coincided with real facial expression skin elastic-deformation. It has been proved to be set up 3D facial parameterized model more rapidly and exactly, and much easier to extract facial characteristic points to be recognized. Meanwhile, it has been proved to be a new idea and reliable theoretical base to 3D facial modeling and make the later face recognition easier.