EllipseDirectFit {conicfit} | R Documentation |
Algebraic ellipse fit method by Fitzgibbon-Pilu-Fisher
Description
EllipseDirectFit
applies the algebraic ellipse fit method
by Fitzgibbon-Pilu-Fisher
Usage
EllipseDirectFit(XY)
Arguments
XY |
array of sample data |
Value
vector(A , B , C , D , E , F) |
vector of algebraic parameters of the fitting ellipse: ax^2 + bxy + cy^2 +dx + ey + f = 0 |
Author(s)
Jose Gama
Source
Nikolai Chernov, 2014 Fitting ellipses, circles, and lines by least squares http://people.cas.uab.edu/~mosya/cl/
A. W. Fitzgibbon, M. Pilu, R. B. Fisher, 1999 Direct Least Squares Fitting of Ellipses IEEE Trans. PAMI, Vol. 21, pages 476-480
A. W. Fitzgibbon, M. Pilu, R. B. Fisher, "Direct Least Squares Fitting of Ellipses", IEEE Trans. PAMI, Vol. 21, pages 476-480 (1999) Halir R, Flusser J (1998) Proceedings of the 6th International Conference in Central Europe on Computer Graphics and Visualization, Numerically stable direct least squares fitting of ellipses (WSCG, Plzen, Czech Republic), pp 125–132.
References
Nikolai Chernov, 2014 Fitting ellipses, circles, and lines by least squares http://people.cas.uab.edu/~mosya/cl/
A. W. Fitzgibbon, M. Pilu, R. B. Fisher, 1999 Direct Least Squares Fitting of Ellipses IEEE Trans. PAMI, Vol. 21, pages 476-480
A. W. Fitzgibbon, M. Pilu, R. B. Fisher, "Direct Least Squares Fitting of Ellipses", IEEE Trans. PAMI, Vol. 21, pages 476-480 (1999) Halir R, Flusser J (1998) Proceedings of the 6th International Conference in Central Europe on Computer Graphics and Visualization, Numerically stable direct least squares fitting of ellipses (WSCG, Plzen, Czech Republic), pp 125–132.
Examples
xy<-calculateEllipse(0,0,200,100,45,50, randomDist=TRUE,noiseFun=function(x)
(x+rnorm(1,mean=0,sd=50)))
plot(xy[,1],xy[,2],xlim=c(-250,250),ylim=c(-250,250),col='magenta');par(new=TRUE)
ellipDirect <- EllipseDirectFit(xy)
ellipDirectG <- AtoG(ellipDirect)$ParG
xyDirect<-calculateEllipse(ellipDirectG[1], ellipDirectG[2], ellipDirectG[3],
ellipDirectG[4], 180/pi*ellipDirectG[5])
plot(xyDirect[,1],xyDirect[,2],xlim=c(-250,250),ylim=c(-250,250),type='l',
col='cyan');par(new=TRUE)