cv::aruco::ArucoDetector Class Reference

The main functionality of ArucoDetector class is detection of markers in an image with detectMarkers() method. More...

#include <opencv2/objdetect/aruco_detector.hpp>

Collaboration diagram for cv::aruco::ArucoDetector:

Public Member Functions
	ArucoDetector (const Dictionary &dictionary=getPredefinedDictionary(cv::aruco::DICT_4X4_50), const DetectorParameters &detectorParams=DetectorParameters(), const RefineParameters &refineParams=RefineParameters())
	Basic ArucoDetector constructor.
void	detectMarkers (InputArray image, OutputArrayOfArrays corners, OutputArray ids, OutputArrayOfArrays rejectedImgPoints=noArray()) const
	Basic marker detection.
const DetectorParameters &	getDetectorParameters () const
const Dictionary &	getDictionary () const
const RefineParameters &	getRefineParameters () const
virtual void	read (const FileNode &fn) override
	Reads algorithm parameters from a file storage.
void	refineDetectedMarkers (InputArray image, const Board &board, InputOutputArrayOfArrays detectedCorners, InputOutputArray detectedIds, InputOutputArrayOfArrays rejectedCorners, InputArray cameraMatrix=noArray(), InputArray distCoeffs=noArray(), OutputArray recoveredIdxs=noArray()) const
	Refine not detected markers based on the already detected and the board layout.
void	setDetectorParameters (const DetectorParameters &detectorParameters)
void	setDictionary (const Dictionary &dictionary)
void	setRefineParameters (const RefineParameters &refineParameters)
virtual void	write (FileStorage &fs) const override
	Stores algorithm parameters in a file storage.
void	write (FileStorage &fs, const String &name)
	simplified API for language bindings
Public Member Functions inherited from cv::Algorithm
	Algorithm ()
virtual	~Algorithm ()
virtual void	clear ()
	Clears the algorithm state.
virtual bool	empty () const
	Returns true if the Algorithm is empty (e.g. in the very beginning or after unsuccessful read.
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

Protected Attributes
Ptr< ArucoDetectorImpl >	arucoDetectorImpl

Additional Inherited Members
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 inherited from cv::Algorithm
void	writeFormat (FileStorage &fs) const

Detailed Description

The main functionality of ArucoDetector class is detection of markers in an image with detectMarkers() method.

After detecting some markers in the image, you can try to find undetected markers from this dictionary with refineDetectedMarkers() method.

See also

DetectorParameters, RefineParameters

Constructor & Destructor Documentation

ArucoDetector()

cv::aruco::ArucoDetector::ArucoDetector	(	const Dictionary &	dictionary = getPredefinedDictionary(cv::aruco::DICT_4X4_50),
		const DetectorParameters &	detectorParams = DetectorParameters(),
		const RefineParameters &	refineParams = RefineParameters()
	)

Python:
	cv.aruco.ArucoDetector(	[, dictionary[, detectorParams[, refineParams]]]	) ->	<aruco_ArucoDetector object>

Basic ArucoDetector constructor.

Parameters

dictionary	indicates the type of markers that will be searched
detectorParams	marker detection parameters
refineParams	marker refine detection parameters

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Member Function Documentation

detectMarkers()

void cv::aruco::ArucoDetector::detectMarkers	(	InputArray	image,
		OutputArrayOfArrays	corners,
		OutputArray	ids,
		OutputArrayOfArrays	rejectedImgPoints = noArray()
	)		const

Python:
	cv.aruco.ArucoDetector.detectMarkers(	image[, corners[, ids[, rejectedImgPoints]]]	) ->	corners, ids, rejectedImgPoints

Basic marker detection.

Parameters

image	input image
corners	vector of detected marker corners. For each marker, its four corners are provided, (e.g std::vector<std::vector<cv::Point2f> > ). For N detected markers, the dimensions of this array is Nx4. The order of the corners is clockwise.
ids	vector of identifiers of the detected markers. The identifier is of type int (e.g. std::vector<int>). For N detected markers, the size of ids is also N. The identifiers have the same order than the markers in the imgPoints array.
rejectedImgPoints	contains the imgPoints of those squares whose inner code has not a correct codification. Useful for debugging purposes.

Performs marker detection in the input image. Only markers included in the specific dictionary are searched. For each detected marker, it returns the 2D position of its corner in the image and its corresponding identifier. Note that this function does not perform pose estimation.

Note

The function does not correct lens distortion or takes it into account. It's recommended to undistort input image with corresponding camera model, if camera parameters are known

See also

undistort, estimatePoseSingleMarkers, estimatePoseBoard

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getDetectorParameters()

const DetectorParameters & cv::aruco::ArucoDetector::getDetectorParameters

(

)

const

Python:
	cv.aruco.ArucoDetector.getDetectorParameters(		) ->	retval

getDictionary()

const Dictionary & cv::aruco::ArucoDetector::getDictionary

(

)

const

Python:
	cv.aruco.ArucoDetector.getDictionary(		) ->	retval

getRefineParameters()

const RefineParameters & cv::aruco::ArucoDetector::getRefineParameters

(

)

const

Python:
	cv.aruco.ArucoDetector.getRefineParameters(		) ->	retval

read()

virtual void cv::aruco::ArucoDetector::read ( const FileNode &  fn )

overridevirtual

Python:
	cv.aruco.ArucoDetector.read(	fn	) ->	None

Reads algorithm parameters from a file storage.

Reimplemented from cv::Algorithm.

refineDetectedMarkers()

void cv::aruco::ArucoDetector::refineDetectedMarkers	(	InputArray	image,
		const Board &	board,
		InputOutputArrayOfArrays	detectedCorners,
		InputOutputArray	detectedIds,
		InputOutputArrayOfArrays	rejectedCorners,
		InputArray	cameraMatrix = noArray(),
		InputArray	distCoeffs = noArray(),
		OutputArray	recoveredIdxs = noArray()
	)		const

Python:
	cv.aruco.ArucoDetector.refineDetectedMarkers(	image, board, detectedCorners, detectedIds, rejectedCorners[, cameraMatrix[, distCoeffs[, recoveredIdxs]]]	) ->	detectedCorners, detectedIds, rejectedCorners, recoveredIdxs

Refine not detected markers based on the already detected and the board layout.

Parameters

image	input image
board	layout of markers in the board.
detectedCorners	vector of already detected marker corners.
detectedIds	vector of already detected marker identifiers.
rejectedCorners	vector of rejected candidates during the marker detection process.
cameraMatrix	optional input 3x3 floating-point camera matrix \(A = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{1}\)
distCoeffs	optional vector of distortion coefficients \((k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6],[s_1, s_2, s_3, s_4]])\) of 4, 5, 8 or 12 elements
recoveredIdxs	Optional array to returns the indexes of the recovered candidates in the original rejectedCorners array.

This function tries to find markers that were not detected in the basic detecMarkers function. First, based on the current detected marker and the board layout, the function interpolates the position of the missing markers. Then it tries to find correspondence between the reprojected markers and the rejected candidates based on the minRepDistance and errorCorrectionRate parameters. If camera parameters and distortion coefficients are provided, missing markers are reprojected using projectPoint function. If not, missing marker projections are interpolated using global homography, and all the marker corners in the board must have the same Z coordinate.

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setDetectorParameters()

void cv::aruco::ArucoDetector::setDetectorParameters

(

const DetectorParameters &

detectorParameters

)

Python:
	cv.aruco.ArucoDetector.setDetectorParameters(	detectorParameters	) ->	None

setDictionary()

void cv::aruco::ArucoDetector::setDictionary

(

const Dictionary &

dictionary

)

Python:
	cv.aruco.ArucoDetector.setDictionary(	dictionary	) ->	None

setRefineParameters()

void cv::aruco::ArucoDetector::setRefineParameters

(

const RefineParameters &

refineParameters

)

Python:
	cv.aruco.ArucoDetector.setRefineParameters(	refineParameters	) ->	None

write() [1/2]

virtual void cv::aruco::ArucoDetector::write ( FileStorage &  fs ) const

overridevirtual

Python:
	cv.aruco.ArucoDetector.write(	fs, name	) ->	None

Stores algorithm parameters in a file storage.

Reimplemented from cv::Algorithm.

write() [2/2]

void cv::aruco::ArucoDetector::write ( FileStorage &  fs, const String &  name  )

inline

Python:
	cv.aruco.ArucoDetector.write(	fs, name	) ->	None

simplified API for language bindings

Member Data Documentation

arucoDetectorImpl

Ptr<ArucoDetectorImpl> cv::aruco::ArucoDetector::arucoDetectorImpl

protected

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

• opencv2/objdetect/aruco_detector.hpp