A Simple Solution to the Six-Point Two-View Focal-Length Problem

  • Hongdong Li
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3954)


This paper presents a simple and practical solution to the 6-point 2-view focal-length estimation problem. Based on the hidden-variable technique we have derived a 15th degree polynomial in the unknown focal-length. During this course, a simple and constructive algorithm is established. To make use of multiple redundant measurements and then select the best solution, we suggest a kernel-voting scheme. The algorithm has been tested on both synthetic data and real images. Satisfactory results are obtained for both cases. For reference purpose we include our Matlab implementation in the paper, which is quite concise, consisting of 20 lines of code only. The result of this paper will make a small but useful module in many computer vision systems.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Hongdong Li
    • 1
  1. 1.RSISEThe Australian National University, National ICTAustralia

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