Homotopy in Digital Spaces

  • Rafael Ayala
  • Eladio Domínguez
  • Angel R. Francés
  • Antonio Quintero
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1953)


The main contribution of this paper is a new “extrinsic” digital fundamental group that can be readily generalized to define higher homotopy groups for arbitrary digital spaces. We show that the digital fundamental group of a digital object is naturally isomorphic to the fundamental group of its continuous analogue. In addition, we state a digital version of the Seifert-Van Kampen theorem.


Digital homotopy digital fundamental group lighting functions Seifert-Van Kampen theorem 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • Rafael Ayala
    • 1
  • Eladio Domínguez
    • 2
  • Angel R. Francés
    • 2
  • Antonio Quintero
    • 1
  1. 1.Dpt. de Geometría y Topología, Facultad de MatemáticasUniversidad de SevillaSevillaSpain
  2. 2.Dpt. de Informática e Ingeniería de Sistemas, Facultad de CienciasUniversidad de ZaragozaZaragozaSpain

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