Statistical modeling of facial aging based on 3D scans

This thesis presents an approach to the modeling of facial aging using and extending the Morphable Model technique. For modeling the face variation across individuals, facial expressions, and physical attributes, we collected 3D face scans of 298 persons. The 3D face scans where acquired with a structured light 3D scanner, which we improved in collaboration with the manufacturer to achieve superior geometry and texture quality. Moreover, we developed an efficient way to measure fine skin structure and reflection properties with the scanner. The collected face scans have been used to build the Basel Face Model, a new publicly available Morphable Model.
Using the 3D scans we learn the correlation between physical attributes such as weight, height, and especially age and faces. With the learned correlation, we present a novel way to simultaneously manipulate different attributes and demonstrate the capability to model changes caused by aging. Using the attributes of the face model in conjunction with a skull model developed in the same research group, we present a method to reconstruct faces from skull shapes which considers physical attributes, as the body weight, age etc.
The most important aspect of facial aging that can not be simulated with the Morphable Model is the appearance of facial wrinkles. In this work we present a novel approach to synthesize age wrinkles based on statistics. Our wrinkle synthesis consists of two main parts: The learning of a generative model of wrinkle constellations, and the modeling of their visual appearance. For learning the constellations we use kernel density estimation of manually labeled wrinkles to estimate the wrinkle occurrence probability. To learn the visual appearance of wrinkles we use the fine scale skin structure captured with our improved scanning method. Our results show that the combination of the attribute fitting based aging and the wrinkle synthesis, facilitate a simulation of visually convincing progressive aging. The method is without restrictions applicable to any face that can be represented by the Morphable Model.