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arXiv · 1612.03308

GraCT: A Grammar based Compressed representation of Trajectories

Nieves R. Brisaboa·Adrián Gómez-Brandón·Gonzalo Navarro·José R. Paramá
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Abstract

We present a compressed data structure to store free trajectories of moving objects (ships over the sea, for example) allowing spatio-temporal queries. Our method, GraCT, uses a $k^2$-tree to store the absolute positions of all objects at regular time intervals (snapshots), whereas the positions between snapshots are represented as logs of relative movements compressed with Re-Pair. Our experimental evaluation shows important savings in space and time with respect to a fair baseline.

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Nieves R. Brisaboa, Adrián Gómez-Brandón, Gonzalo Navarro, José R. Paramá. 2016-12-10. GraCT: A Grammar based Compressed representation of Trajectories. https://doi.org/10.1007/978-3-319-46049-9_21

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