Facial Feature Extraction using Eigenspaces and Deformable Graphs
Jörgen Ahlberg · 2007
In model-based coding of image sequences containing human faces, eg videophone sequences, the detection and location of the face as well as the extraction of facial features from the images are crucial. The facial feature extraction can be regarded as an optimization problem, searching the optimum adaptation parameters of the model. The optimum is defined as the parameter set describing the face with the minimum distance to a face space. There are different approaches to reduce the high computational complexity, and here a scheme using deformable graphs and dynamic programming is described. Experiments have been performed with promising results. 1. MODEL-BASED CODING Since the major application of the techniques described in this document is model-based coding, an introduction to that topic will follow here. For more details, see eg [8] or [12]. The basic idea of model-based coding of video sequences is illustrated in Figure 1. At the encoding side of a visual communication system (...