Falconn++: A Locality-sensitive Filtering Approach for Approximate Nearest Neighbor Search

Falconn can filter out potential far away points in any hash bucket before querying, which results in higher quality candidates compared to other hashing-based solutions. Theoretically, Falconn asymptotically achieves lower query time complexity than Falconn, an optimal locality-sensitive hashing scheme on angular distance. Empirically, Falconn achieves a higher recall-speed tradeoff than Falconn on many real-world data sets. Falconn is also competitive with HNSW, an efficient representative of graph-based solutions on high search recall regimes.