Codes for Multiplexing Images and Lighting
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                   Yoav Schechner*
             Dept. of Electrical Engineering
          Technion - Israel Inst. of Technology
               www.ee.technion.ac.il/~yoav


Imaging of objects under variable lighting directions is an important and frequent practice
in computer vision and image-based rendering. We introduce an approach that significantly
improves the quality of such images, practically at no cost. 

Traditional methods for acquiring images under variable illumination directions use only 
a single light source per acquired image. In contrast, our approach is based on a multiplexing 
principle, in which multiple light sources illuminate the object simultaneously from different 
directions. Thus, the object irradiance is much higher. The acquired images are then computationally 
demultiplexed. 

We give the optimal code by which the illumination should be multiplexed to obtain the
highest quality output. We then demonstrate its utility in experiments using high directional 
resolution lighting. The mathematical principle behind this approach is useful in other domains 
of imaging, unrelated to the regime of illumination.

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* Joint work with Shree Nayar and Peter Belhumeur