Module imagingbook.common

Package imagingbook.common.geometry.fitting.circle.algebraic

Class CircleFitTaubin

java.lang.Object

imagingbook.common.geometry.fitting.circle.algebraic.CircleFitTaubin

All Implemented Interfaces:

CircleFitAlgebraic

public class CircleFitTaubin
extends Object
implements CircleFitAlgebraic

This is an implementation of the algebraic circle fitting algorithm by Taubin [1], following the description in [2] (Sec. 5.9-5.10).

The algorithm uses singular-value decomposition (SVD). Fits to exactly 3 (non-collinear) points are handled properly. Data centering is used to improve numerical stability (alternatively, a reference point can be specified).

[1] G. Taubin. "Estimation of planar curves, surfaces, and nonplanar space curves defined by implicit equations with applications to edge and range image segmentation". IEEE Transactions on Pattern Analysis and Machine Intelligence 13(11), 1115–1138 (1991).
[2] N. Chernov. "Circular and Linear Regression: Fitting Circles and Lines by Least Squares". Monographs on Statistics and Applied Probability. Taylor & Francis (2011).

Nested Class Summary

Nested classes/interfaces inherited from interface imagingbook.common.geometry.fitting.circle.algebraic.CircleFitAlgebraic

CircleFitAlgebraic.FitType

Constructor Summary

Constructors

Constructor	Description
CircleFitTaubin(Pnt2d[] points)	Constructor.
CircleFitTaubin(Pnt2d[] points, Pnt2d xref)	Constructor.

Method Summary

Modifier and Type	Method	Description
double[]	getParameters()	Returns parameters (A, B, C, D) of the AlgebraicCircle or null if the fit was unsuccessful.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface imagingbook.common.geometry.fitting.circle.algebraic.CircleFitAlgebraic

getAlgebraicCircle, getGeometricCircle, normalizeP

Constructor Details

CircleFitTaubin

public CircleFitTaubin(Pnt2d[] points)

Constructor. The centroid of the sample points is used as the reference point.

Parameters:

points - sample points

CircleFitTaubin

public CircleFitTaubin(Pnt2d[] points,
 Pnt2d xref)

Constructor. The centroid of the sample points is used as the reference point for data centering if null is passed for xref.

Parameters:

points - sample points

xref - reference point or null

Method Details

getParameters

public double[] getParameters()

Description copied from interface: CircleFitAlgebraic

Returns parameters (A, B, C, D) of the AlgebraicCircle or null if the fit was unsuccessful. Parameters are not normalized.

Specified by:

getParameters in interface CircleFitAlgebraic

Returns:

the algebraic circle parameters or null