An Output-Sensitive Algorithm for the Minimization of 2-Dimensional String Covers

  • Alexandru PopaEmail author
  • Andrei Tanasescu
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11436)


String covers are a powerful tool for analyzing the quasi-periodicity of 1-dimensional data and find applications in automata theory, computational biology, coding and the analysis of transactional data. A cover of a string T is a string C for which every letter of T lies within some occurrence of C. String covers have been generalized in many ways, leading to k-covers, \(\lambda \)-covers, approximate covers and were studied in different contexts such as indeterminate strings.

In this paper we generalize string covers to the context of 2-dimensional data, such as images. We show how they can be used for the extraction of textures from images and identification of primitive cells in lattice data. This has interesting applications in image compression, procedural terrain generation and crystallography.


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.University of BucharestBucharestRomania
  2. 2.National Institute of Research and Development in InformaticsBucharestRomania
  3. 3.Politehnica University of BucharestBucharestRomania

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