A Single-Scan Algorithm for Connected Components Labelling in a Traffic Monitoring Application

  • Alessandro Bevilacqua
  • Alessandro Lanza
  • Giorgio Baccarani
  • Riccardo Rovatti
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2749)


This paper presents a fast algorithm based on sequential local operations which aims at labelling connected components in binary images. While classical algorithms scan the image twice and utilize an equiv alencetable to store and resolve label redundancies, our method performs just a single scan, relying on the idea of labelling a whole blob at a time. In this way, we avoid label redundancies. As a consequence, the use of both equivalence tables and algorithms to resolve them becomes unnecessary. This leads our labelling algorithm to attain even more significant performances in the case of images characterized by blobs generating a large number of label equivalences. The proposed labelling algorithm has been successfully utilized in our visual surveillance system.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Alessandro Bevilacqua
    • 1
  • Alessandro Lanza
    • 1
  • Giorgio Baccarani
    • 1
  • Riccardo Rovatti
    • 1
  1. 1.ARCES - Centre of Excellence, DEIS (Department of Electronics, Computer Science and Systems)University of BolognaBolognaItaly

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