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Conic Fitting Problem

The problem is to fit a conic section to a set of n points tex2html_wrap_inline2565 ( tex2html_wrap_inline2549 ). A conic can be described by the following equation:


where A and C are not simultaneously zero. In practice, we encounter ellipses, where we must impose the constraint tex2html_wrap_inline2573 . However, this constraint is usually ignored during the fitting because

As the data are noisy, it is unlikely to find a set of parameters (A, B, C, D, E, F) (except for the trivial solution A=B=C=D=E=F=0) such that tex2html_wrap_inline2579 , tex2html_wrap_inline2581 . Instead, we will try to estimate them by minimizing some objective function.

Zhengyou Zhang
Thu Feb 8 11:42:20 MET 1996