g2o::RobustKernelHuber Class Reference

Huber Cost Function. More...

#include <robust_kernel_impl.h>

Inheritance diagram for g2o::RobustKernelHuber:

Collaboration diagram for g2o::RobustKernelHuber:

Public Member Functions
virtual void	robustify (double e2, Vector3D &rho) const
Public Member Functions inherited from g2o::RobustKernel
	RobustKernel ()
	RobustKernel (double delta)
virtual	~RobustKernel ()
virtual void	setDelta (double delta)
double	delta () const

Additional Inherited Members
Protected Attributes inherited from g2o::RobustKernel
double	_delta

Detailed Description

Huber Cost Function.

Loss function as described by Huber See http://en.wikipedia.org/wiki/Huber_loss_function

If e^(1/2) < d rho(e) = e

else

          1/2    2

rho(e) = 2 d e - d

Definition at line 77 of file robust_kernel_impl.h.

Member Function Documentation

void g2o::RobustKernelHuber::robustify ( double  squaredError, Vector3D &  rho  ) const

virtual

compute the scaling factor for a error: The error is e^T Omega e The output rho is rho[0]: The actual scaled error value rho[1]: First derivative of the scaling function rho[2]: Second derivative of the scaling function

Implements g2o::RobustKernel.

Definition at line 65 of file robust_kernel_impl.cpp.

References g2o::RobustKernel::_delta.

{
  double dsqr = _delta * _delta;
  if (e <= dsqr) { // inlier
    rho[0] = e;
    rho[1] = 1.;
    rho[2] = 0.;
  } else { // outlier
    double sqrte = sqrt(e); // absolut value of the error
    rho[0] = 2*sqrte*_delta - dsqr; // rho(e)   = 2 * delta * e^(1/2) - delta^2
    rho[1] = _delta / sqrte;        // rho'(e)  = delta / sqrt(e)
    rho[2] = - 0.5 * rho[1] / e;    // rho''(e) = -1 / (2*e^(3/2)) = -1/2 * (delta/e) / e
  }
}

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The documentation for this class was generated from the following files:

• /home/xuezhisd/CLionProjects/g2o/g2o/core/robust_kernel_impl.h
• /home/xuezhisd/CLionProjects/g2o/g2o/core/robust_kernel_impl.cpp