Characterization of associative recall in a volume holographic database system for multimedia applications
Pericles A. Mitkas, George A. Betzos, S. Mailis, Nikolaos A. Vainos · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1998
Multimedia applications require high capacity and data transfer rates from secondary storage. Volume holographic memories are attractive because they can satisfy these requirements in the near future. These memories use a 2D page-oriented data format and they can perform associative recall of the data stored in them which is an important operation in a database system. We have conducted a set of experiments to characterize the associative recall in a volume holographic database system set up in our laboratory. We show that associate recall is very feasible and can perform with binary and grey scale data or a combination of both. We present results from experiments in terms of three applications: a) database management, b) interactive video, and c) video indexing. We show that the search argument can be quite small, however problems with sufficient optical power arise when the search argument is too small. For this reason we have also conducted experiments with optical amplification of the output signal from an optical memory. These experiments also indicate that photorefractive amplifiers perform well in such a system and can be used to increase the associative recall signal levels.