GraCT: A Grammar based Compressed representation of Trajectories
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.
- Publication:
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arXiv e-prints
- Pub Date:
- December 2016
- DOI:
- 10.48550/arXiv.1612.03308
- arXiv:
- arXiv:1612.03308
- Bibcode:
- 2016arXiv161203308B
- Keywords:
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- Computer Science - Data Structures and Algorithms
- E-Print:
- This research has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sk{\l}odowska-Curie Actions H2020-MSCA-RISE-2015 BIRDS GA No. 690941