Flann-based descriptor matcher. More...

#include <opencv2/features2d.hpp>

Collaboration diagram for cv::FlannBasedMatcher:

Public Member Functions
	FlannBasedMatcher (const Ptr< flann::IndexParams > &indexParams=makePtr< flann::KDTreeIndexParams >(), const Ptr< flann::SearchParams > &searchParams=makePtr< flann::SearchParams >())

virtual void	add (InputArrayOfArrays descriptors) CV_OVERRIDE
	Adds descriptors to train a CPU(trainDescCollectionis) or GPU(utrainDescCollectionis) descriptor collection.

virtual void	clear () CV_OVERRIDE
	Clears the train descriptor collections.

virtual CV_NODISCARD_STD Ptr< DescriptorMatcher >	clone (bool emptyTrainData=false) const CV_OVERRIDE
	Clones the matcher.

virtual bool	isMaskSupported () const CV_OVERRIDE
	Returns true if the descriptor matcher supports masking permissible matches.

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

virtual void	train () CV_OVERRIDE
	Trains a descriptor matcher.

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

Public Member Functions inherited from cv::DescriptorMatcher
virtual	~DescriptorMatcher ()

virtual bool	empty () const CV_OVERRIDE
	Returns true if there are no train descriptors in the both collections.

const std::vector< Mat > &	getTrainDescriptors () const
	Returns a constant link to the train descriptor collection trainDescCollection .

void	knnMatch (InputArray queryDescriptors, InputArray trainDescriptors, std::vector< std::vector< DMatch > > &matches, int k, InputArray mask=noArray(), bool compactResult=false) const
	Finds the k best matches for each descriptor from a query set.

void	knnMatch (InputArray queryDescriptors, std::vector< std::vector< DMatch > > &matches, int k, InputArrayOfArrays masks=noArray(), bool compactResult=false)

void	match (InputArray queryDescriptors, InputArray trainDescriptors, std::vector< DMatch > &matches, InputArray mask=noArray()) const
	Finds the best match for each descriptor from a query set.

void	match (InputArray queryDescriptors, std::vector< DMatch > &matches, InputArrayOfArrays masks=noArray())

void	radiusMatch (InputArray queryDescriptors, InputArray trainDescriptors, std::vector< std::vector< DMatch > > &matches, float maxDistance, InputArray mask=noArray(), bool compactResult=false) const
	For each query descriptor, finds the training descriptors not farther than the specified distance.

void	radiusMatch (InputArray queryDescriptors, std::vector< std::vector< DMatch > > &matches, float maxDistance, InputArrayOfArrays masks=noArray(), bool compactResult=false)

void	read (const String &fileName)

void	write (const Ptr< FileStorage > &fs, const String &name) const

void	write (const String &fileName) const

void	write (FileStorage &fs, const String &name) const

Public Member Functions inherited from cv::Algorithm
	Algorithm ()

virtual	~Algorithm ()

virtual String	getDefaultName () const

virtual void	save (const String &filename) const

void	write (const Ptr< FileStorage > &fs, const String &name=String()) const

void	write (FileStorage &fs, const String &name) const

Static Public Member Functions
static Ptr< FlannBasedMatcher >	create ()

Static Public Member Functions inherited from cv::DescriptorMatcher
static Ptr< DescriptorMatcher >	create (const DescriptorMatcher::MatcherType &matcherType)

static Ptr< DescriptorMatcher >	create (const String &descriptorMatcherType)
	Creates a descriptor matcher of a given type with the default parameters (using default constructor).

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

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

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

Protected Member Functions
virtual void	knnMatchImpl (InputArray queryDescriptors, std::vector< std::vector< DMatch > > &matches, int k, InputArrayOfArrays masks=noArray(), bool compactResult=false) CV_OVERRIDE

virtual void	radiusMatchImpl (InputArray queryDescriptors, std::vector< std::vector< DMatch > > &matches, float maxDistance, InputArrayOfArrays masks=noArray(), bool compactResult=false) CV_OVERRIDE

Protected Member Functions inherited from cv::DescriptorMatcher
void	checkMasks (InputArrayOfArrays masks, int queryDescriptorsCount) const

Protected Member Functions inherited from cv::Algorithm
void	writeFormat (FileStorage &fs) const

Static Protected Member Functions
static void	convertToDMatches (const DescriptorCollection &descriptors, const Mat &indices, const Mat &distances, std::vector< std::vector< DMatch > > &matches)

Static Protected Member Functions inherited from cv::DescriptorMatcher
static CV_NODISCARD_STD Mat	clone_op (Mat m)

static bool	isMaskedOut (InputArrayOfArrays masks, int queryIdx)

static bool	isPossibleMatch (InputArray mask, int queryIdx, int trainIdx)

Protected Attributes
int	addedDescCount

Ptr< flann::Index >	flannIndex

Ptr< flann::IndexParams >	indexParams

DescriptorCollection	mergedDescriptors

Ptr< flann::SearchParams >	searchParams

Protected Attributes inherited from cv::DescriptorMatcher
std::vector< Mat >	trainDescCollection
	Collection of descriptors from train images.

std::vector< UMat >	utrainDescCollection

Additional Inherited Members
Public Types inherited from cv::DescriptorMatcher
enum	MatcherType { FLANNBASED = 1 , BRUTEFORCE = 2 , BRUTEFORCE_L1 = 3 , BRUTEFORCE_HAMMING = 4 , BRUTEFORCE_HAMMINGLUT = 5 , BRUTEFORCE_SL2 = 6 }

Detailed Description

Flann-based descriptor matcher.

This matcher trains cv::flann::Index on a train descriptor collection and calls its nearest search methods to find the best matches. So, this matcher may be faster when matching a large train collection than the brute force matcher. FlannBasedMatcher does not support masking permissible matches of descriptor sets because flann::Index does not support this. :

Examples: samples/cpp/snippets/epipolar_lines.cpp.

Constructor & Destructor Documentation

◆ FlannBasedMatcher()

cv::FlannBasedMatcher::FlannBasedMatcher	(	const Ptr< flann::IndexParams > &	indexParams = `makePtr< flann::KDTreeIndexParams >()`,
		const Ptr< flann::SearchParams > &	searchParams = `makePtr< flann::SearchParams >()`
	)

Python:
	cv.FlannBasedMatcher(	[, indexParams[, searchParams]]	) ->	<FlannBasedMatcher object>

Member Function Documentation

◆ add()

virtual void cv::FlannBasedMatcher::add ( InputArrayOfArrays descriptors )

virtual

Adds descriptors to train a CPU(trainDescCollectionis) or GPU(utrainDescCollectionis) descriptor collection.

If the collection is not empty, the new descriptors are added to existing train descriptors.

Parameters

descriptors Descriptors to add. Each descriptors[i] is a set of descriptors from the same train image.

Reimplemented from cv::DescriptorMatcher.

◆ clear()

virtual void cv::FlannBasedMatcher::clear ( )

virtual

Clears the train descriptor collections.

Reimplemented from cv::DescriptorMatcher.

◆ clone()

virtual CV_NODISCARD_STD Ptr< DescriptorMatcher > cv::FlannBasedMatcher::clone ( bool emptyTrainData = false ) const

virtual

Clones the matcher.

Parameters

emptyTrainData If emptyTrainData is false, the method creates a deep copy of the object, that is, copies both parameters and train data. If emptyTrainData is true, the method creates an object copy with the current parameters but with empty train data.

Implements cv::DescriptorMatcher.

◆ convertToDMatches()

static void cv::FlannBasedMatcher::convertToDMatches	(	const DescriptorCollection &	descriptors,
		const Mat &	indices,
		const Mat &	distances,
		std::vector< std::vector< DMatch > > &	matches
	)

staticprotected

◆ create()

static Ptr< FlannBasedMatcher > cv::FlannBasedMatcher::create ( )

static

Python:
	cv.FlannBasedMatcher.create(		) ->	retval
	cv.FlannBasedMatcher_create(		) ->	retval

◆ isMaskSupported()

virtual bool cv::FlannBasedMatcher::isMaskSupported ( ) const

virtual

Returns true if the descriptor matcher supports masking permissible matches.

Implements cv::DescriptorMatcher.

◆ knnMatchImpl()

virtual void cv::FlannBasedMatcher::knnMatchImpl	(	InputArray	queryDescriptors,
		std::vector< std::vector< DMatch > > &	matches,
		int	k,
		InputArrayOfArrays	masks = `noArray()`,
		bool	compactResult = `false`
	)

protectedvirtual

In fact the matching is implemented only by the following two methods. These methods suppose that the class object has been trained already. Public match methods call these methods after calling train().

Implements cv::DescriptorMatcher.

◆ radiusMatchImpl()

virtual void cv::FlannBasedMatcher::radiusMatchImpl	(	InputArray	queryDescriptors,
		std::vector< std::vector< DMatch > > &	matches,
		float	maxDistance,
		InputArrayOfArrays	masks = `noArray()`,
		bool	compactResult = `false`
	)

protectedvirtual

Implements cv::DescriptorMatcher.

◆ read()

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

virtual

Reads algorithm parameters from a file storage.

Reimplemented from cv::DescriptorMatcher.

◆ train()

virtual void cv::FlannBasedMatcher::train ( )

virtual

Trains a descriptor matcher.

Trains a descriptor matcher (for example, the flann index). In all methods to match, the method train() is run every time before matching. Some descriptor matchers (for example, BruteForceMatcher) have an empty implementation of this method. Other matchers really train their inner structures (for example, FlannBasedMatcher trains flann::Index ).

Reimplemented from cv::DescriptorMatcher.

◆ write()

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

virtual

Stores algorithm parameters in a file storage.

Reimplemented from cv::DescriptorMatcher.

Member Data Documentation

◆ addedDescCount

int cv::FlannBasedMatcher::addedDescCount

protected

◆ flannIndex

Ptr<flann::Index> cv::FlannBasedMatcher::flannIndex

protected

◆ indexParams

Ptr<flann::IndexParams> cv::FlannBasedMatcher::indexParams

protected

◆ mergedDescriptors

DescriptorCollection cv::FlannBasedMatcher::mergedDescriptors

protected

◆ searchParams

Ptr<flann::SearchParams> cv::FlannBasedMatcher::searchParams

protected

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

opencv2/features2d.hpp

Public Member Functions

Static Public Member Functions

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ FlannBasedMatcher()

Member Function Documentation

◆ add()

◆ clear()

◆ clone()

◆ convertToDMatches()

◆ create()

◆ isMaskSupported()

◆ knnMatchImpl()

◆ radiusMatchImpl()

◆ read()

◆ train()

◆ write()

Member Data Documentation

◆ addedDescCount

◆ flannIndex

◆ indexParams

◆ mergedDescriptors

◆ searchParams