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arXiv · 1809.02350

FRESH: Fr\'echet Similarity with Hashing

Matteo Ceccarello·Anne Driemel·Francesco Silvestri
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Abstract

This paper studies the $r$-range search problem for curves under the continuous Fr\'echet distance: given a dataset $S$ of $n$ polygonal curves and a threshold $r>0$, construct a data structure that, for any query curve $q$, efficiently returns all entries in $S$ with distance at most $r$ from $q$. We propose FRESH, an approximate and randomized approach for $r$-range search, that leverages on a locality sensitive hashing scheme for detecting candidate near neighbors of the query curve, and on a subsequent pruning step based on a cascade of curve simplifications. We experimentally compare \fresh to exact and deterministic solutions, and we show that high performance can be reached by suitably relaxing precision and recall.

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Matteo Ceccarello, Anne Driemel, Francesco Silvestri. 2018-09-07. FRESH: Fr\'echet Similarity with Hashing. https://arxiv.org/abs/1809.02350

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