Implementation of the Shape Context descriptor and matching algorithm. More...

#include "shape_distance.hpp"

Inheritance diagram for cv::ShapeContextDistanceExtractor:

Collaboration diagram for cv::ShapeContextDistanceExtractor:

Public Member Functions
virtual void	clear ()
	Clears the algorithm state. More...

virtual float	computeDistance (InputArray contour1, InputArray contour2)=0
	Compute the shape distance between two shapes defined by its contours. More...

virtual bool	empty () const
	Returns true if the Algorithm is empty (e.g. More...

virtual int	getAngularBins () const =0

virtual float	getBendingEnergyWeight () const =0

virtual Ptr< HistogramCostExtractor >	getCostExtractor () const =0

virtual String	getDefaultName () const
	Returns the algorithm string identifier. More...

virtual float	getImageAppearanceWeight () const =0

virtual void	getImages (OutputArray image1, OutputArray image2) const =0

virtual float	getInnerRadius () const =0

virtual int	getIterations () const =0

virtual float	getOuterRadius () const =0

virtual int	getRadialBins () const =0

virtual bool	getRotationInvariant () const =0

virtual float	getShapeContextWeight () const =0

virtual float	getStdDev () const =0

virtual Ptr< ShapeTransformer >	getTransformAlgorithm () const =0

virtual void	read (const FileNode &fn)
	Reads algorithm parameters from a file storage. More...

virtual void	save (const String &filename) const
	Saves the algorithm to a file. More...

virtual void	setAngularBins (int nAngularBins)=0
	Establish the number of angular bins for the Shape Context Descriptor used in the shape matching pipeline. More...

virtual void	setBendingEnergyWeight (float bendingEnergyWeight)=0
	Set the weight of the Bending Energy in the final value of the shape distance. More...

virtual void	setCostExtractor (Ptr< HistogramCostExtractor > comparer)=0
	Set the algorithm used for building the shape context descriptor cost matrix. More...

virtual void	setImageAppearanceWeight (float imageAppearanceWeight)=0
	Set the weight of the Image Appearance cost in the final value of the shape distance. More...

virtual void	setImages (InputArray image1, InputArray image2)=0
	Set the images that correspond to each shape. More...

virtual void	setInnerRadius (float innerRadius)=0
	Set the inner radius of the shape context descriptor. More...

virtual void	setIterations (int iterations)=0

virtual void	setOuterRadius (float outerRadius)=0
	Set the outer radius of the shape context descriptor. More...

virtual void	setRadialBins (int nRadialBins)=0
	Establish the number of radial bins for the Shape Context Descriptor used in the shape matching pipeline. More...

virtual void	setRotationInvariant (bool rotationInvariant)=0

virtual void	setShapeContextWeight (float shapeContextWeight)=0
	Set the weight of the shape context distance in the final value of the shape distance. More...

virtual void	setStdDev (float sigma)=0
	Set the value of the standard deviation for the Gaussian window for the image appearance cost. More...

virtual void	setTransformAlgorithm (Ptr< ShapeTransformer > transformer)=0
	Set the algorithm used for aligning the shapes. More...

virtual void	write (FileStorage &fs) const
	Stores algorithm parameters in a file storage. More...

Static Public Member Functions
template<typename _Tp >
static Ptr< _Tp >	load (const String &filename, const String &objname=String())
	Loads algorithm from the file. More...

template<typename _Tp >
static Ptr< _Tp >	loadFromString (const String &strModel, const String &objname=String())
	Loads algorithm from a String. More...

template<typename _Tp >
static Ptr< _Tp >	read (const FileNode &fn)
	Reads algorithm from the file node. More...

Protected Member Functions
void	writeFormat (FileStorage &fs) const

Detailed Description

Implementation of the Shape Context descriptor and matching algorithm.

proposed by Belongie et al. in "Shape Matching and Object Recognition Using Shape Contexts" (PAMI 2002). This implementation is packaged in a generic scheme, in order to allow you the implementation of the common variations of the original pipeline.

Member Function Documentation

virtual void cv::Algorithm::clear ( )

inlinevirtualinherited

Clears the algorithm state.

Reimplemented in cv::FlannBasedMatcher, cv::DescriptorMatcher, and cv::cuda::DescriptorMatcher.

virtual float cv::ShapeDistanceExtractor::computeDistance	(	InputArray	contour1,
		InputArray	contour2
	)

pure virtualinherited

Compute the shape distance between two shapes defined by its contours.

Parameters

contour1	Contour defining first shape.
contour2	Contour defining second shape.

virtual bool cv::Algorithm::empty ( ) const

inlinevirtualinherited

Returns true if the Algorithm is empty (e.g.

in the very beginning or after unsuccessful read

Reimplemented in cv::DescriptorMatcher, cv::ml::StatModel, cv::Feature2D, cv::BaseCascadeClassifier, and cv::cuda::DescriptorMatcher.

virtual int cv::ShapeContextDistanceExtractor::getAngularBins ( ) const

pure virtual

virtual float cv::ShapeContextDistanceExtractor::getBendingEnergyWeight ( ) const

pure virtual

virtual Ptr<HistogramCostExtractor> cv::ShapeContextDistanceExtractor::getCostExtractor ( ) const

pure virtual

virtual String cv::Algorithm::getDefaultName ( ) const

virtualinherited

Returns the algorithm string identifier.

This string is used as top level xml/yml node tag when the object is saved to a file or string.

virtual float cv::ShapeContextDistanceExtractor::getImageAppearanceWeight ( ) const

pure virtual

virtual void cv::ShapeContextDistanceExtractor::getImages	(	OutputArray	image1,
		OutputArray	image2
	)		const

pure virtual

virtual float cv::ShapeContextDistanceExtractor::getInnerRadius ( ) const

pure virtual

virtual int cv::ShapeContextDistanceExtractor::getIterations ( ) const

pure virtual

virtual float cv::ShapeContextDistanceExtractor::getOuterRadius ( ) const

pure virtual

virtual int cv::ShapeContextDistanceExtractor::getRadialBins ( ) const

pure virtual

virtual bool cv::ShapeContextDistanceExtractor::getRotationInvariant ( ) const

pure virtual

virtual float cv::ShapeContextDistanceExtractor::getShapeContextWeight ( ) const

pure virtual

virtual float cv::ShapeContextDistanceExtractor::getStdDev ( ) const

pure virtual

virtual Ptr<ShapeTransformer> cv::ShapeContextDistanceExtractor::getTransformAlgorithm ( ) const

pure virtual

template<typename _Tp >

static Ptr<_Tp> cv::Algorithm::load	(	const String &	filename,
		const String &	objname = `String()`
	)

inlinestaticinherited

Loads algorithm from the file.

Parameters

filename	Name of the file to read.
objname	The optional name of the node to read (if empty, the first top-level node will be used)

This is static template method of Algorithm. It's usage is following (in the case of SVM):

Ptr<SVM> svm = Algorithm::load<SVM>("my_svm_model.xml");

In order to make this method work, the derived class must overwrite Algorithm::read(const FileNode& fn).

References cv::Ptr< T >::empty(), cv::FileNode::empty(), cv::FileStorage::getFirstTopLevelNode(), and cv::FileStorage::READ.

Here is the call graph for this function:

template<typename _Tp >

static Ptr<_Tp> cv::Algorithm::loadFromString	(	const String &	strModel,
		const String &	objname = `String()`
	)

inlinestaticinherited

Loads algorithm from a String.

Parameters

strModel	The string variable containing the model you want to load.
objname	The optional name of the node to read (if empty, the first top-level node will be used)

This is static template method of Algorithm. It's usage is following (in the case of SVM):

Ptr<SVM> svm = Algorithm::loadFromString<SVM>(myStringModel);

References CV_WRAP, cv::Ptr< T >::empty(), cv::FileNode::empty(), cv::FileStorage::getFirstTopLevelNode(), cv::FileStorage::MEMORY, and cv::FileStorage::READ.

Here is the call graph for this function:

virtual void cv::Algorithm::read ( const FileNode & fn )

inlinevirtualinherited

Reads algorithm parameters from a file storage.

Reimplemented in cv::FlannBasedMatcher, cv::DescriptorMatcher, and cv::Feature2D.

template<typename _Tp >

static Ptr<_Tp> cv::Algorithm::read ( const FileNode & fn )

inlinestaticinherited

Reads algorithm from the file node.

This is static template method of Algorithm. It's usage is following (in the case of SVM):

cv::FileStorage fsRead("example.xml", FileStorage::READ);

Ptr<SVM> svm = Algorithm::read<SVM>(fsRead.root());

In order to make this method work, the derived class must overwrite Algorithm::read(const FileNode& fn) and also have static create() method without parameters (or with all the optional parameters)

References cv::Ptr< T >::empty().

Here is the call graph for this function:

virtual void cv::Algorithm::save ( const String & filename ) const

virtualinherited

Saves the algorithm to a file.

In order to make this method work, the derived class must implement Algorithm::write(FileStorage& fs).

virtual void cv::ShapeContextDistanceExtractor::setAngularBins ( int nAngularBins )

pure virtual

Establish the number of angular bins for the Shape Context Descriptor used in the shape matching pipeline.

Parameters

nAngularBins The number of angular bins in the shape context descriptor.

virtual void cv::ShapeContextDistanceExtractor::setBendingEnergyWeight ( float bendingEnergyWeight )

pure virtual

Set the weight of the Bending Energy in the final value of the shape distance.

The bending energy definition depends on what transformation is being used to align the shapes. The final value of the shape distance is a user-defined linear combination of the shape context distance, an image appearance distance, and a bending energy.

Parameters

bendingEnergyWeight The weight of the Bending Energy in the final distance value.

virtual void cv::ShapeContextDistanceExtractor::setCostExtractor ( Ptr< HistogramCostExtractor > comparer )

pure virtual

Set the algorithm used for building the shape context descriptor cost matrix.

Parameters

comparer Smart pointer to a HistogramCostExtractor, an algorithm that defines the cost matrix between descriptors.

virtual void cv::ShapeContextDistanceExtractor::setImageAppearanceWeight ( float imageAppearanceWeight )

pure virtual

Set the weight of the Image Appearance cost in the final value of the shape distance.

The image appearance cost is defined as the sum of squared brightness differences in Gaussian windows around corresponding image points. The final value of the shape distance is a user-defined linear combination of the shape context distance, an image appearance distance, and a bending energy. If this value is set to a number different from 0, is mandatory to set the images that correspond to each shape.

Parameters

imageAppearanceWeight The weight of the appearance cost in the final distance value.

virtual void cv::ShapeContextDistanceExtractor::setImages	(	InputArray	image1,
		InputArray	image2
	)

pure virtual

Set the images that correspond to each shape.

This images are used in the calculation of the Image Appearance cost.

Parameters

image1	Image corresponding to the shape defined by contours1.
image2	Image corresponding to the shape defined by contours2.

virtual void cv::ShapeContextDistanceExtractor::setInnerRadius ( float innerRadius )

pure virtual

Set the inner radius of the shape context descriptor.

Parameters

innerRadius The value of the inner radius.

virtual void cv::ShapeContextDistanceExtractor::setIterations ( int iterations )

pure virtual

virtual void cv::ShapeContextDistanceExtractor::setOuterRadius ( float outerRadius )

pure virtual

Set the outer radius of the shape context descriptor.

Parameters

outerRadius The value of the outer radius.

virtual void cv::ShapeContextDistanceExtractor::setRadialBins ( int nRadialBins )

pure virtual

Establish the number of radial bins for the Shape Context Descriptor used in the shape matching pipeline.

Parameters

nRadialBins The number of radial bins in the shape context descriptor.

virtual void cv::ShapeContextDistanceExtractor::setRotationInvariant ( bool rotationInvariant )

pure virtual

virtual void cv::ShapeContextDistanceExtractor::setShapeContextWeight ( float shapeContextWeight )

pure virtual

Set the weight of the shape context distance in the final value of the shape distance.

The shape context distance between two shapes is defined as the symmetric sum of shape context matching costs over best matching points. The final value of the shape distance is a user-defined linear combination of the shape context distance, an image appearance distance, and a bending energy.

Parameters

shapeContextWeight The weight of the shape context distance in the final distance value.

virtual void cv::ShapeContextDistanceExtractor::setStdDev ( float sigma )

pure virtual

Set the value of the standard deviation for the Gaussian window for the image appearance cost.

Parameters

sigma Standard Deviation.

virtual void cv::ShapeContextDistanceExtractor::setTransformAlgorithm ( Ptr< ShapeTransformer > transformer )

pure virtual

Set the algorithm used for aligning the shapes.

Parameters

transformer Smart pointer to a ShapeTransformer, an algorithm that defines the aligning transformation.

virtual void cv::Algorithm::write ( FileStorage & fs ) const

inlinevirtualinherited

Stores algorithm parameters in a file storage.

Reimplemented in cv::FlannBasedMatcher, cv::DescriptorMatcher, and cv::Feature2D.

void cv::Algorithm::writeFormat ( FileStorage & fs ) const

protectedinherited

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

shape/include/opencv2/shape/shape_distance.hpp

Public Member Functions

Static Public Member Functions

Protected Member Functions

Detailed Description

Member Function Documentation