A Review of Selected Multiple Light Source Detection Methods

1 Hougen and Ahuja This 1993 paper [2] is the first method to approach the multiple light source problem. It uses a combination of stereo, light source estimation, and shape from shading methods for determining the shape of objects. This summary will focus on the proposed light source estimation technique and it’s integration in the system. Four main assumptions are stated: 1. The light sources are distant point light sources. 2. There is no shadowing on visible objects. 3. There are no interreflections between visible objects. 4. The luminance must appear as a multiplicative constant in the reflectance function. They also mention that the technique works best if the reflectance function is not highly specular. For a single light source the irradiance from a surface region is defined by