Illumination Normalization using Quotient Image-based Techniques

This chapter focuses on correctly recognizing faces in the presence of large illumination variation. Our aim is to do this by synthesizing an illumination normalized image using Quotient Image-based techniques (Shashua et al., 2001, Wang et al., 2004, Chen et al., 2005, Nishiyama et al., 2006, Zhang et al., 2007, and An et al., 2008). These techniques extract an illumination invariant representation of a face from a raw facial image. To discuss the variation of facial appearances caused by illumination, the appearances are classified into four main components: diffuse reflection, specular reflection, attached shadow and cast shadow (See Figure 1) as described in (Shashua, 1999).