FLASH: FPGA Locality-Aware Sensitive Hash for Nearest Neighbor Search and Clustering Application

A locality sensitive hash (LSH) is a function to identify similar items in data sets. However, traditional LSH based algorithms are rarely implemented on hardware due to the high demand of computation, which limits its usage. In this paper, we propose a novel LSH design and hardware implementation called FPGA locality-aware sensitive hash (FLASH). With the unique hardware delay generated during the fabrication process, a FLASH can reduce the dimensionality of coordinate distance calculation and improve the efficiency of nearest neighbor search (NNS). It is also applied to 2-D image clustering. The experimental results show the practical value of our FLASH applications.