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itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage > Class Template Reference

#include <itkCannyEdgeDetectionImageFilter.h>

Inheritance diagram for itk::CannyEdgeDetectionImageFilter:

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Collaboration diagram for itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >:

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List of all members.

Public Types

typedef CannyEdgeDetectionImageFilter Self
typedef ImageToImageFilter<
TInputImage, TOutputImage > 
Superclass
typedef TInputImage InputImageType
typedef TOutputImage OutputImageType
typedef SmartPointer< SelfPointer
typedef SmartPointer< const
Self
ConstPointer
typedef TInputImage::PixelType InputImagePixelType
typedef TOutputImage::PixelType OutputImagePixelType
typedef ZeroFluxNeumannBoundaryCondition<
OutputImageType
DefaultBoundaryConditionType
typedef ConstNeighborhoodIterator<
OutputImageType
NeighborhoodType
typedef ConstSmartNeighborhoodIterator<
OutputImageType, DefaultBoundaryConditionType
BoundaryNeighborhoodType
typedef TOutputImage::RegionType OutputImageRegionType

Public Methods

virtual const char * GetClassName () const
 itkStaticConstMacro (ImageDimension, unsigned int, TInputImage::ImageDimension)
virtual void SetThreshold (OutputImagePixelType _arg)
virtual OutputImagePixelType GetThreshold ()
virtual void SetOutsideValue (OutputImagePixelType _arg)
virtual OutputImagePixelType GetOutsideValue ()
virtual void GenerateInputRequestedRegion () throw (InvalidRequestedRegionError)
virtual void SetVariance (double data[])
virtual const double * GetVariance () const
virtual void SetMaximumError (double data[])
virtual const double * GetMaximumError () const
void SetVariance (const double v)
void SetMaximumError (const double v)

Static Public Methods

Pointer New ()

Protected Methods

 CannyEdgeDetectionImageFilter ()
 CannyEdgeDetectionImageFilter (const Self &)
void PrintSelf (std::ostream &os, Indent indent) const
void GenerateData ()

Detailed Description

template<class TInputImage, class TOutputImage>
class itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >

This filter is an implementation of a Canny edge detector for scalar-valued images. Based on John Canny's paper "A Computational Approach to Edge Detection"(IEEE Transactions on Pattern Analysis and Machine Intelligence, Vol. PAMI-8, No.6, November 1986), there are four major steps used in the edge-detection scheme: (1) The input image is smoothed using a Gaussian filter. (2) The zero-crossings of the second derivative of the smoothed image are found. (3) The zero-crossing image is multiplied (pixel-wise) with the second-derivative gradient image of the smoothed image. (4) The resulting image is thresholded to eliminate uninteresting edges.
Inputs and Outputs
The input to this filter should be a scalar, real-valued Itk image of arbitrary dimension. The output should also be a scalar, real-value Itk image of the same dimensionality.
Parameters
There are four parameters for this filter that control the sub-filters used by the algorithm.

Variance and Maximum error are used in the Gaussian smoothing of the input image. See itkDiscreteGaussianImageFilter for information on these parameters.

Threshold is the lowest allowed value in the output image. Its data type is the same as the data type of the output image. Any values below the Threshold level will be replaced with the OutsideValue parameter value, whose default is zero.

Todo:
Edge-linking will be added when an itk connected component labeling algorithm is available.

See also:
DiscreteGaussianImageFilter , ZeroCrossingImageFilter , ThresholdImageFilter

Definition at line 71 of file itkCannyEdgeDetectionImageFilter.h.


Member Typedef Documentation

template<class TInputImage, class TOutputImage>
typedef ConstSmartNeighborhoodIterator<OutputImageType, DefaultBoundaryConditionType> itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::BoundaryNeighborhoodType
 

The type of data structure that is passed to this function object to evaluate at a pixel that lies on a data set boundary.

Definition at line 104 of file itkCannyEdgeDetectionImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef SmartPointer<const Self> itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::ConstPointer
 

Reimplemented from itk::ImageToImageFilter< TInputImage, TOutputImage >.

Definition at line 85 of file itkCannyEdgeDetectionImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef ZeroFluxNeumannBoundaryCondition<OutputImageType> itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::DefaultBoundaryConditionType
 

The default boundary condition is used unless overridden in the Evaluate() method.

Definition at line 94 of file itkCannyEdgeDetectionImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef TInputImage::PixelType itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::InputImagePixelType
 

Define pixel types.

Reimplemented from itk::ImageToImageFilter< TInputImage, TOutputImage >.

Definition at line 88 of file itkCannyEdgeDetectionImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef TInputImage itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::InputImageType
 

Image typedef support

Reimplemented from itk::ImageToImageFilter< TInputImage, TOutputImage >.

Definition at line 80 of file itkCannyEdgeDetectionImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef ConstNeighborhoodIterator<OutputImageType> itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::NeighborhoodType
 

The type of data structure that is passed to this function object to evaluate at a pixel that does not lie on a data set boundary.

Definition at line 99 of file itkCannyEdgeDetectionImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef TOutputImage::PixelType itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::OutputImagePixelType
 

Reimplemented from itk::ImageSource< TOutputImage >.

Definition at line 89 of file itkCannyEdgeDetectionImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef TOutputImage::RegionType itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::OutputImageRegionType
 

Typedef to describe the output image region type.

Reimplemented from itk::ImageToImageFilter< TInputImage, TOutputImage >.

Definition at line 110 of file itkCannyEdgeDetectionImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef TOutputImage itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::OutputImageType
 

Some convenient typedefs.

Reimplemented from itk::ImageSource< TOutputImage >.

Definition at line 81 of file itkCannyEdgeDetectionImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef SmartPointer<Self> itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::Pointer
 

SmartPointer typedef support

Reimplemented from itk::ImageToImageFilter< TInputImage, TOutputImage >.

Definition at line 84 of file itkCannyEdgeDetectionImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef CannyEdgeDetectionImageFilter itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::Self
 

Standard "Self" & Superclass typedef.

Reimplemented from itk::ImageToImageFilter< TInputImage, TOutputImage >.

Definition at line 76 of file itkCannyEdgeDetectionImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef ImageToImageFilter<TInputImage, TOutputImage> itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::Superclass
 

Reimplemented from itk::ImageToImageFilter< TInputImage, TOutputImage >.

Definition at line 77 of file itkCannyEdgeDetectionImageFilter.h.


Constructor & Destructor Documentation

template<class TInputImage, class TOutputImage>
itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::CannyEdgeDetectionImageFilter   [protected]
 

template<class TInputImage, class TOutputImage>
itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::CannyEdgeDetectionImageFilter const Self   [inline, protected]
 

Definition at line 165 of file itkCannyEdgeDetectionImageFilter.h.

References HardConnectedComponentImageFilter::GenerateData().


Member Function Documentation

template<class TInputImage, class TOutputImage>
void itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::GenerateData   [protected, virtual]
 

A version of GenerateData() specific for image processing filters. This implementation will split the processing across multiple threads. The buffer is allocated by this method. Then the BeforeThreadedGenerateData() method is called (if provided). Then, a series of threads are spawned each calling ThreadedGenerateData(). After all the threads have completed processing, the AfterThreadedGenerateData() method is called (if provided). If an image processing filter cannot be threaded, the filter should provide an implementation of GenerateData(). That implementation is responsible for allocating the output buffer. If a filter an be threaded, it should NOT provide a GenerateData() method but should provide a ThreadedGenerateData() instead.

See also:
ThreadedGenerateData()

Reimplemented from itk::ImageSource< TOutputImage >.

template<class TInputImage, class TOutputImage>
virtual void itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::GenerateInputRequestedRegion   throw (InvalidRequestedRegionError) [virtual]
 

CannyEdgeDetectionImageFilter needs a larger input requested region than the output requested region ( derivative operators, etc). As such, CannyEdgeDetectionImageFilter needs to provide an implementation for GenerateInputRequestedRegion() in order to inform the pipeline execution model.

See also:
ImageToImageFilter::GenerateInputRequestedRegion()

Reimplemented from itk::ImageToImageFilter< TInputImage, TOutputImage >.

template<class TInputImage, class TOutputImage>
virtual const char* itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::GetClassName   const [virtual]
 

Run-time type information (and related methods).

Reimplemented from itk::ImageToImageFilter< TInputImage, TOutputImage >.

template<class TInputImage, class TOutputImage>
virtual const double* itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::GetMaximumError   const [virtual]
 

Standard get/set macros for filter parameters.

template<class TInputImage, class TOutputImage>
virtual OutputImagePixelType itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::GetOutsideValue   [virtual]
 

template<class TInputImage, class TOutputImage>
virtual OutputImagePixelType itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::GetThreshold   [virtual]
 

template<class TInputImage, class TOutputImage>
virtual const double* itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::GetVariance   const [virtual]
 

Standard get/set macros for filter parameters.

template<class TInputImage, class TOutputImage>
itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::itkStaticConstMacro ImageDimension   ,
unsigned    int,
TInputImage::ImageDimension   
 

ImageDimension constant

Reimplemented from itk::ImageToImageFilter< TInputImage, TOutputImage >.

template<class TInputImage, class TOutputImage>
Pointer itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::New   [static]
 

Method for creation through the object factory.

Reimplemented from itk::ImageToImageFilter< TInputImage, TOutputImage >.

template<class TInputImage, class TOutputImage>
void itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::PrintSelf std::ostream &    os,
Indent    indent
const [protected, virtual]
 

Methods invoked by Print() to print information about the object including superclasses. Typically not called by the user (use Print() instead) but used in the hierarchical print process to combine the output of several classes.

Reimplemented from itk::ImageToImageFilter< TInputImage, TOutputImage >.

template<class TInputImage, class TOutputImage>
void itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::SetMaximumError const double    v [inline]
 

Set/Get the MaximumError paramter used by the Gaussian smoothing filter in this algorithm

Definition at line 138 of file itkCannyEdgeDetectionImageFilter.h.

template<class TInputImage, class TOutputImage>
virtual void itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::SetMaximumError double    data[] [virtual]
 

Standard get/set macros for filter parameters.

template<class TInputImage, class TOutputImage>
virtual void itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::SetOutsideValue OutputImagePixelType    _arg [virtual]
 

template<class TInputImage, class TOutputImage>
virtual void itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::SetThreshold OutputImagePixelType    _arg [virtual]
 

template<class TInputImage, class TOutputImage>
void itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::SetVariance const double    v [inline]
 

Set/Get the Variance parameter used by the Gaussian smoothing filter in this algorithm

Definition at line 128 of file itkCannyEdgeDetectionImageFilter.h.

template<class TInputImage, class TOutputImage>
virtual void itk::CannyEdgeDetectionImageFilter< TInputImage, TOutputImage >::SetVariance double    data[] [virtual]
 

Standard get/set macros for filter parameters.


The documentation for this class was generated from the following file:
Generated at Wed Mar 12 01:14:54 2003 for ITK by doxygen 1.2.15 written by Dimitri van Heesch, © 1997-2000