itk::SobelOperator< TPixel, VDimension, TAllocator > Class Template Reference

ITK 4.1.0

Insight Segmentation and Registration Toolkit

#include <itkSobelOperator.h>

Inheritance diagram for itk::SobelOperator< TPixel, VDimension, TAllocator >:

Collaboration diagram for itk::SobelOperator< TPixel, VDimension, TAllocator >:

List of all members.

Public Types
typedef SobelOperator	Self
typedef NeighborhoodOperator < TPixel, VDimension, TAllocator >	Superclass
Public Member Functions
virtual void	CreateDirectional ()
virtual const char *	GetNameOfClass () const
	SobelOperator ()
	SobelOperator (const Self &other)

Self &	operator= (const Self &other)

virtual void	PrintSelf (std::ostream &os, Indent i) const
Protected Types
typedef Superclass::CoefficientVector	CoefficientVector
typedef Superclass::PixelType	PixelType
Protected Member Functions
void	Fill (const CoefficientVector &c)
CoefficientVector	GenerateCoefficients ()

Detailed Description

template<class TPixel, unsigned int VDimension = 2, class TAllocator = NeighborhoodAllocator< TPixel >>
class itk::SobelOperator< TPixel, VDimension, TAllocator >

A NeighborhoodOperator for performing a directional Sobel edge-detection operation at a pixel location.

SobelOperator is a directional NeighborhoodOperator that should be applied a NeighborhoodIterator using the NeighborhoodInnerProduct method. To create the operator:

1) Set the direction by calling

 SetDirection

2) call

 itk::Size<2> radius;
 radius.Fill(1);
 sobelOperator.CreateToRadius(radius);

3) You may optionally scale the coefficients of this operator using the

 ScaleCoefficients

method. This is useful if you want to take the spacing of the image into account when computing the edge strength. Apply the scaling only after calling to

 CreateToRadius

.

The Sobel Operator in vertical direction for 2 dimensions is

 *             -1  -2  -1
 *             0    0   0
 *             1    2   1
 *
 *

The Sobel Operator in horizonal direction is for 2 dimensions is

 *             -1   0   1
 *             -2   0   2
 *             -1   0   1
 *

The current implementation of the Sobel operator is for 2 and 3 dimensions only. The ND version is planned for future releases.

The extension to 3D is from the publication "Irwin Sobel. An Isotropic 3x3x3 Volume Gradient Operator. Technical report, Hewlett-Packard Laboratories, April 1995."

The Sobel operator in 3D has the kernel

 * -1 -3 -1   0 0 0  1 3 1
 * -3 -6 -3   0 0 0  3 6 3
 * -1 -3 -1   0 0 0  1 3 1
 *
 *    x-1       x     x+1
 *

The x kernel is just rotated as required to obtain the kernel in the y and z directions.

See also:: NeighborhoodOperator; Neighborhood; ForwardDifferenceOperator; BackwardDifferenceOperator

Wiki Examples:

All Examples

Create the Sobel kernel

Definition at line 96 of file itkSobelOperator.h.

Member Typedef Documentation

template<class TPixel, unsigned int VDimension = 2, class TAllocator = NeighborhoodAllocator< TPixel >>

typedef Superclass::CoefficientVector itk::SobelOperator< TPixel, VDimension, TAllocator >::CoefficientVector [protected]

Typedef support for coefficient vector type. Necessary to work around compiler bug on VC++.

Reimplemented from itk::NeighborhoodOperator< TPixel, VDimension, TAllocator >.

Definition at line 153 of file itkSobelOperator.h.

template<class TPixel, unsigned int VDimension = 2, class TAllocator = NeighborhoodAllocator< TPixel >>

typedef Superclass::PixelType itk::SobelOperator< TPixel, VDimension, TAllocator >::PixelType [protected]

External support for pixel type

Reimplemented from itk::NeighborhoodOperator< TPixel, VDimension, TAllocator >.

Definition at line 154 of file itkSobelOperator.h.

template<class TPixel, unsigned int VDimension = 2, class TAllocator = NeighborhoodAllocator< TPixel >>

typedef SobelOperator itk::SobelOperator< TPixel, VDimension, TAllocator >::Self

Standard typedefs

Reimplemented from itk::NeighborhoodOperator< TPixel, VDimension, TAllocator >.

Definition at line 102 of file itkSobelOperator.h.

template<class TPixel, unsigned int VDimension = 2, class TAllocator = NeighborhoodAllocator< TPixel >>

typedef NeighborhoodOperator< TPixel, VDimension, TAllocator > itk::SobelOperator< TPixel, VDimension, TAllocator >::Superclass

Reimplemented from itk::NeighborhoodOperator< TPixel, VDimension, TAllocator >.

Definition at line 103 of file itkSobelOperator.h.

Constructor & Destructor Documentation

template<class TPixel, unsigned int VDimension = 2, class TAllocator = NeighborhoodAllocator< TPixel >>

itk::SobelOperator< TPixel, VDimension, TAllocator >::SobelOperator ( ) [inline]

Definition at line 107 of file itkSobelOperator.h.

template<class TPixel, unsigned int VDimension = 2, class TAllocator = NeighborhoodAllocator< TPixel >>

itk::SobelOperator< TPixel, VDimension, TAllocator >::SobelOperator ( const Self & other ) [inline]

Definition at line 108 of file itkSobelOperator.h.

Member Function Documentation

template<class TPixel, unsigned int VDimension = 2, class TAllocator = NeighborhoodAllocator< TPixel >>

virtual void itk::SobelOperator< TPixel, VDimension, TAllocator >::CreateDirectional ( ) [inline, virtual]

Creates the operator with length only in the specified direction. For the Sobel operator, this The radius of the operator will be 0 except along the axis on which the operator will work.

See also:: CreateToRadius; FillCenteredDirectional; SetDirection(); GetDirection()

Reimplemented from itk::NeighborhoodOperator< TPixel, VDimension, TAllocator >.

Definition at line 117 of file itkSobelOperator.h.

template<class TPixel, unsigned int VDimension = 2, class TAllocator = NeighborhoodAllocator< TPixel >>

void itk::SobelOperator< TPixel, VDimension, TAllocator >::Fill ( const CoefficientVector & c ) [protected, virtual]

Arranges coefficients spatially in the memory buffer.

Implements itk::NeighborhoodOperator< TPixel, VDimension, TAllocator >.

template<class TPixel, unsigned int VDimension = 2, class TAllocator = NeighborhoodAllocator< TPixel >>

CoefficientVector itk::SobelOperator< TPixel, VDimension, TAllocator >::GenerateCoefficients ( ) [protected, virtual]

Calculates operator coefficients.

Implements itk::NeighborhoodOperator< TPixel, VDimension, TAllocator >.

template<class TPixel, unsigned int VDimension = 2, class TAllocator = NeighborhoodAllocator< TPixel >>

virtual const char* itk::SobelOperator< TPixel, VDimension, TAllocator >::GetNameOfClass ( ) const [virtual]

template<class TPixel, unsigned int VDimension = 2, class TAllocator = NeighborhoodAllocator< TPixel >>

Self& itk::SobelOperator< TPixel, VDimension, TAllocator >::operator= ( const Self & other ) [inline]

Creates the operator with a specified radius ("square", same length on each side). The spatial location of the coefficients within the operator is defined by the subclass implementation of the Fill method.

See also:: CreateDirectional; Fill Assignment operator

Reimplemented from itk::NeighborhoodOperator< TPixel, VDimension, TAllocator >.

Definition at line 131 of file itkSobelOperator.h.

template<class TPixel, unsigned int VDimension = 2, class TAllocator = NeighborhoodAllocator< TPixel >>

virtual void itk::SobelOperator< TPixel, VDimension, TAllocator >::PrintSelf	(	std::ostream &	os,
		Indent	i
	)		const `[inline, virtual]`

Prints some debugging information

Reimplemented from itk::NeighborhoodOperator< TPixel, VDimension, TAllocator >.

Definition at line 141 of file itkSobelOperator.h.

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

itkSobelOperator.h