boofcv.alg.geo.pose

Class Relinearlize

java.lang.Object

boofcv.alg.geo.pose.Relinearlize

public class Relinearlize
extends Object

Used in case 4 of EPnP. See [1] for details. This technique appears to not be all that accurate in practice, but better than nothing. Or maybe there is a bug in the implementation below since even with perfect data it appears to generate large errors. One possible source of implementation error is that the entire null space is not being used. More of the null space (particularly in the planar case) could be used if more relinearization was run multiple times.

[1] Aviad Kipnis and Adi Shamir, "Cryptanalysis of HPE Public Key Cryptosystem" 1999

Author:

Peter Abeles

Constructor Summary

Constructors

Constructor and Description
Relinearlize()

Method Summary

Methods

Modifier and Type	Method and Description
void	process(org.ejml.data.DenseMatrix64F L_full, org.ejml.data.DenseMatrix64F y, double[] betas) Estimates betas using relinearization.
void	setNumberControl(int numControl) Specified the number of control points.
protected org.ejml.data.DenseMatrix64F	solveConstraintMatrix() Apply additional constraints to reduce the number of possible solutions x(k) = x_{ij} = bi*bj = x0(k) + a1*V0(k) + a2*V1(k) + a3*V2(k) constraint: x_{ii}*x_{jk} = x_{ik}*x_{ji}
double	valueNull(int which, int index)

Methods inherited from class java.lang.Object

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

Constructor Detail

Relinearlize

public Relinearlize()

Method Detail

setNumberControl

public void setNumberControl(int numControl)

Specified the number of control points.

Parameters:

numControl - 3 = planar, 4 = general

process

public void process(org.ejml.data.DenseMatrix64F L_full,
           org.ejml.data.DenseMatrix64F y,
           double[] betas)

Estimates betas using relinearization.

Parameters:

L_full - Linear constraint matrix

y - distances between world control points

betas - Estimated betas. Output.

solveConstraintMatrix

protected org.ejml.data.DenseMatrix64F solveConstraintMatrix()

Apply additional constraints to reduce the number of possible solutions x(k) = x_{ij} = bi*bj = x0(k) + a1*V0(k) + a2*V1(k) + a3*V2(k) constraint: x_{ii}*x_{jk} = x_{ik}*x_{ji}

valueNull

public double valueNull(int which,
               int index)