A Simple Approach to Recognise Geometric Shapes Interactively

  • Joaquim A. Jorge
  • Manuel J. Fonseca
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1941)


This paper presents a simple method to recognise multistroke sketches of geometric shapes. It uses temporal adjacency and global geometric properties of figures to recognise a simple vocabulary of geometric shapes including solid and dashed line styles, selection and delete gestures. The geometric features used (convex hull, smallest-area regular polygons, perimeter and area scalar ratios) are invariant with rotation and scale of figures. We have found the method very usable with acceptable recognition rates although the multi-stroke approach poses problems in choosing appropriate values for time-outs. Although we have privileged simplicity over robustness, the method has proved suitable for interactive applications.


Convex Hull Recognition Rate Geometric Shape Thinness Ratio Handwriting Recognition 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • Joaquim A. Jorge
    • 1
  • Manuel J. Fonseca
    • 1
  1. 1.Departamento de Engenharia InformáticaIST/UTLLisboaPortugal

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