@InProceedings{Bujnak-Kukelova-Pajdla-CVPR-2008-InProceedings,
  IS = { zkontrolovano 30 Dec 2008 },
  UPDATE  = { 2008-05-13 },
  key =         {Bujnak-Kukelova-Pajdla-CVPR-2008},
  author =      {Bujnak, Martin and Kukelova, Zuzana and Pajdla, Tomas},
  title =       {A general solution to the p4p problem for 
    camera with unknown focal length},
  year =        {2008},
  pages =       {8},
  booktitle =   {CVPR 2008: Proceedings of the 2008 IEEE Computer Society
    Conference on Computer Vision and Pattern Recognition},
  isbn = {978-1-4244-2243-2},
  issn = {1063-6919},
  book_pages =  {2954},
  publisher = {Omnipress},
  address =  {Madison, USA},
  month =       {June},
  day =         {24-26},
  venue =       {Anchorage, USA},
  organization ={IEEE Computer Society},
  annote = {This paper presents a general solution to the
    determination of the pose of a perspective camera with unknown
    focal length from images of four 3D reference points. Our problem
    is a generalization of the P3P and P4P problems previously
    developed for fully calibrated cameras. Given four 2D-to-3D
    correspondences, we estimate camera position, orientation and
    recover the camera focal length. We formulate the problem and
    provide a minimal solution from four points by solving a system of
    algebraic equations. We compare the Hidden variable resultant and
    Gr\"{o}bner basis techniques for solving the algebraic equations
    of our problem.  By evaluating them on synthetic and on real-data,
    we show that the Gr\"{o}bner basis technique provides stable
    results.  },
  keywords =    {P3P, P4P, Gr\"{o}bner basis, minimal problems, hidden variable},
  authorship =  {34-33-33},
  project =     {MRTN-CT-2004-005439 VISIONTRAIN, FP6-IST-027787 DIRAC, 
    MSM6840770038, STINT Dur IG2003-2 062, MSMT Kontakt 9-06-17},
  psurl       = { [PDF] },
  www         = {  Martin Bujnak ,  Zuzana Kukelova ,  Tomas Pajdla },
  prestige    = { important },
  note        = { CD-ROM },
}