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.
The different versions of the original document can be found in:
Published on 01/01/2016
Volume 2016, 2016
DOI: 10.1007/978-3-319-46049-9_21
Licence: Other
Are you one of the authors of this document?