Ellipse Fitting with Hyperaccuracy

  • Kenichi Kanatani
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3951)


For fitting an ellipse to a point sequence, ML (maximum likelihood) has been regarded as having the highest accuracy. In this paper, we demonstrate the existence of a “hyperaccurate” method which outperforms ML. This is made possible by error analysis of ML followed by subtraction of high-order bias terms. Since ML nearly achieves the theoretical accuracy bound (the KCR lower bound), the resulting improvement is very small. Nevertheless, our analysis has theoretical significance, illuminating the relationship between ML and the KCR lower bound.


Thick Solid Line Thin Solid Line Order Error Point Sequence True Shape 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Kenichi Kanatani
    • 1
  1. 1.Department of Computer ScienceOkayama UniversityOkayamaJapan

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