OpenCV ArUco marker tracker class derived from CVTracked. More...

#include <CVTrackedAruco.h>

Inheritance diagram for CVTrackedAruco:

Public Member Functions
	CVTrackedAruco (int arucoID, string calibIniPath)

const CVArucoParams &	params () const

bool	track (CVMat imageGray, CVMat imageBgr, CVCalibration *calib)
	Tracks the all Aruco markers in the given image for the first sceneview. More...

Public Member Functions inherited from CVTracked
	CVTracked ()

virtual	~CVTracked ()=default

void	drawDetection (bool draw)

bool	isVisible ()

bool	drawDetection ()

CVMatx44f	objectViewMat ()

Static Public Member Functions
static void	drawArucoMarkerBoard (int dictionaryId, int numMarkersX, int numMarkersY, float markerEdgeLengthM, float markerSepaM, const string &imgName, float dpi=254.0f, bool showImage=false)
	Helper function to draw and save an aruco marker board image. More...

static void	drawArucoMarker (int dictionaryId, int minMarkerId, int maxMarkerId, int markerSizePX=200)
	Helper function to draw and save an aruco marker set. More...

Static Public Member Functions inherited from CVTracked
static cv::Matx44f	createGLMatrix (const CVMat &tVec, const CVMat &rVec)
	Create an OpenGL 4x4 matrix from an OpenCV translation & rotation vector. More...

static void	createRvecTvec (const CVMatx44f &glMat, CVMat &tVec, CVMat &rVec)
	Creates the OpenCV rvec & tvec vectors from an column major OpenGL 4x4 matrix. More...

static CVMatx44f	calcObjectMatrix (const CVMatx44f &cameraObjectMat, const CVMatx44f &objectViewMat)

static CVVec3f	averageVector (vector< CVVec3f > vectors, vector< float > weights)

static SLQuat4f	averageQuaternion (vector< SLQuat4f > quaternions, vector< float > weights)

static void	resetTimes ()
	Resets all static variables. More...

Protected Member Functions
bool	trackAll (CVMat imageGray, CVMat imageBgr, CVCalibration *calib, CVRect roi=CVRect(0, 0, 0, 0))

Protected Attributes
vector< int >	arucoIDs
	detected Aruco marker IDs More...

CVVMatx44f	objectViewMats
	object view matrices for all found markers More...

Protected Attributes inherited from CVTracked
bool	_isVisible
	Flag if marker is visible. More...

bool	_drawDetection
	Flag if detection should be drawn into image. More...

CVMatx44f	_objectViewMat
	view transformation matrix More...

HighResTimer	_timer
	High resolution timer. More...

Private Attributes
CVArucoParams	_params
	Aruco parameters. More...

int	_arucoID
	Aruco Marker ID for this node. More...

string	_calibIniPath

Additional Inherited Members
Static Public Attributes inherited from CVTracked
static AvgFloat	trackingTimesMS
	Averaged time for video tracking in ms. More...

static AvgFloat	detectTimesMS
	Averaged time for video feature detection & description in ms. More...

static AvgFloat	detect1TimesMS
	Averaged time for video feature detection subpart 1 in ms. More...

static AvgFloat	detect2TimesMS
	Averaged time for video feature detection subpart 2 in ms. More...

static AvgFloat	matchTimesMS
	Averaged time for video feature matching in ms. More...

static AvgFloat	optFlowTimesMS
	Averaged time for video feature optical flow tracking in ms. More...

static AvgFloat	poseTimesMS
	Averaged time for video feature pose estimation in ms. More...

Detailed Description

OpenCV ArUco marker tracker class derived from CVTracked.

Tracking class for ArUco markers tracking. See the official OpenCV docs on ArUco markers: http://docs.opencv.org/3.1.0/d5/dae/tutorial_aruco_detection.html The aruco marker used in the SLProject are printed in a PDF stored in the data/Calibration folder. They use the dictionary 0 and where generated with the functions CVTrackedAruco::drawArucoMarkerBoard and CVTrackedAruco::drawArucoMarker.

Definition at line 130 of file CVTrackedAruco.h.

Constructor & Destructor Documentation

◆ CVTrackedAruco()

CVTrackedAruco::CVTrackedAruco	(	int	arucoID,
		string	calibIniPath
	)

explicit

Definition at line 23 of file CVTrackedAruco.cpp.

   : _calibIniPath(calibIniPath),
     _arucoID(arucoID)
 {
     SLbool paramsLoaded = _params.loadFromFile(_calibIniPath);
  
     if (!paramsLoaded)
         Utils::exitMsg("SLProject",
                        "CVTrackedAruco::track: Failed to load Aruco parameters.",
                        __LINE__,
                        __FILE__);
 }

Member Function Documentation

◆ drawArucoMarker()

void CVTrackedAruco::drawArucoMarker	(	int	dictionaryId,
		int	minMarkerId,
		int	maxMarkerId,
		int	markerSizePX = `200`
	)

static

Helper function to draw and save an aruco marker set.

Definition at line 251 of file CVTrackedAruco.cpp.

 {
     assert(dictionaryId > 0);
     assert(minMarkerId > 0);
     assert(minMarkerId < maxMarkerId);
  
 #if CV_MAJOR_VERSION < 4 || CV_MINOR_VERSION < 7
     cv::Ptr<cv::aruco::Dictionary> dict = getPredefinedDictionary(cv::aruco::PREDEFINED_DICTIONARY_NAME(dictionaryId));
     if (maxMarkerId > dict->bytesList.rows)
         maxMarkerId = dict->bytesList.rows;
  
     CVMat markerImg;
  
     for (int i = minMarkerId; i < maxMarkerId; ++i)
     {
         cv::aruco::drawMarker(dict, i, markerSizePX, markerImg, 1);
 #    ifndef __EMSCRIPTEN__
         imwrite(Utils::formatString("ArucoMarker_Dict%d_%dpx_Id%d.png",
                                     dictionaryId,
                                     markerSizePX,
                                     i),
                 markerImg);
 #    endif
     }
 #else
     cv::aruco::Dictionary dict = getPredefinedDictionary(cv::aruco::PredefinedDictionaryType(dictionaryId));
     if (maxMarkerId > dict.bytesList.rows)
         maxMarkerId = dict.bytesList.rows;
  
     CVMat markerImg;
  
     for (int i = minMarkerId; i < maxMarkerId; ++i)
     {
         cv::aruco::generateImageMarker(dict,
                                        i,
                                        markerSizePX,
                                        markerImg,
                                        1);
 #    ifndef __EMSCRIPTEN__
         imwrite(Utils::formatString("ArucoMarker_Dict%d_%dpx_Id%d.png",
                                     dictionaryId,
                                     markerSizePX,
                                     i),
                 markerImg);
 #    endif
     }
 #endif
 }

◆ drawArucoMarkerBoard()

void CVTrackedAruco::drawArucoMarkerBoard	(	int	dictionaryId,
		int	numMarkersX,
		int	numMarkersY,
		float	markerEdgeM,
		float	markerSepaM,
		const string &	imgName,
		float	dpi = `254.0f`,
		bool	showImage = `false`
	)

static

Helper function to draw and save an aruco marker board image.

CVTrackedAruco::drawArucoMarkerBoard draws and saves an aruco board into an image.

Parameters

dictionaryId	integer id of the dictionary
numMarkersX	NO. of markers in x-direction
numMarkersY	NO. of markers in y-direction
markerEdgeM	Length of one marker in meters
markerSepaM	Separation between markers in meters
imgName	Image filename inclusive format extension
dpi	Dots per inch (default 256)
showImage	Shows image in window ( default false)

Definition at line 184 of file CVTrackedAruco.cpp.

 {
 #if CV_MAJOR_VERSION < 4 || CV_MINOR_VERSION < 7
     cv::Ptr<cv::aruco::Dictionary> dictionary = cv::aruco::getPredefinedDictionary(cv::aruco::PREDEFINED_DICTIONARY_NAME(dictionaryId));
     cv::Ptr<cv::aruco::GridBoard>  board      = cv::aruco::GridBoard::create(numMarkersX,
                                                                        numMarkersY,
                                                                        markerEdgeM,
                                                                        markerSepaM,
                                                                        dictionary);
     CVSize                         imageSize;
     imageSize.width  = (int)((markerEdgeM + markerSepaM) * 100.0f / 2.54f * dpi * (float)numMarkersX);
     imageSize.height = (int)((markerEdgeM + markerSepaM) * 100.0f / 2.54f * dpi * (float)numMarkersY);
  
     imageSize.width -= (imageSize.width % 4);
     imageSize.height -= (imageSize.height % 4);
  
     // show created board
     CVMat boardImage;
     board->draw(imageSize, boardImage, 0, 1);
  
     if (showImage)
     {
         imshow("board", boardImage);
         cv::waitKey(0);
     }
 #else
     cv::aruco::Dictionary dictionary = cv::aruco::getPredefinedDictionary(cv::aruco::PredefinedDictionaryType(dictionaryId));
     cv::aruco::GridBoard  board      = cv::aruco::GridBoard(cv::Size(numMarkersX, numMarkersY),
                                                       markerEdgeM,
                                                       markerSepaM,
                                                       dictionary);
  
     CVSize imageSize;
     imageSize.width  = (int)((markerEdgeM + markerSepaM) * 100.0f / 2.54f * dpi * (float)numMarkersX);
     imageSize.height = (int)((markerEdgeM + markerSepaM) * 100.0f / 2.54f * dpi * (float)numMarkersY);
  
     imageSize.width -= (imageSize.width % 4);
     imageSize.height -= (imageSize.height % 4);
  
     // show created board
     CVMat boardImage;
     cv::aruco::drawPlanarBoard(&board,
                                imageSize,
                                boardImage,
                                0,
                                1);
 #    ifndef __EMSCRIPTEN__
     if (showImage)
     {
         imshow("board", boardImage);
         cv::waitKey(0);
     }
 #    endif
 #endif
  
 #ifndef __EMSCRIPTEN__
     imwrite(imgName, boardImage);
 #endif
 }

◆ params()

const CVArucoParams& CVTrackedAruco::params ( ) const

inline

Definition at line 136 of file CVTrackedAruco.h.

136 { return _params; }

◆ track()

bool CVTrackedAruco::track	(	CVMat	imageGray,
		CVMat	imageBgr,
		CVCalibration *	calib
	)

virtual

Tracks the all Aruco markers in the given image for the first sceneview.

Implements CVTracked.

Reimplemented in CVTrackedArucoCube.

Definition at line 37 of file CVTrackedAruco.cpp.

 {
     if (!trackAll(imageGray, imageBgr, calib))
     {
         return false;
     }
  
     if (!arucoIDs.empty())
     {
         // Find the marker with the matching id
         for (size_t i = 0; i < arucoIDs.size(); ++i)
         {
             if (arucoIDs[i] == _arucoID)
             {
                 _objectViewMat = objectViewMats[i];
                 return true;
             }
         }
     }
  
     return false;
 }

◆ trackAll()

bool CVTrackedAruco::trackAll	(	CVMat	imageGray,
		CVMat	imageBgr,
		CVCalibration *	calib,
		CVRect	roi = `CVRect(0, 0, 0, 0)`
	)

protected

Definition at line 62 of file CVTrackedAruco.cpp.

 {
     PROFILE_FUNCTION();
  
     assert(!imageGray.empty() && "ImageGray is empty");
     assert(!imageBgr.empty() && "ImageBGR is empty");
     assert(!calib->cameraMat().empty() && "Calibration is empty");
  
 #if CV_MAJOR_VERSION < 4 || CV_MINOR_VERSION < 7
     if (_params.arucoParams.empty() || _params.dictionary.empty())
     {
         Utils::warnMsg("SLProject",
                        "CVTrackedAruco::track: Aruco paramters are empty.",
                        __LINE__,
                        __FILE__);
         return false;
     }
 #endif
  
     ////////////
     // Detect //
     ////////////
  
     CVMat croppedImageGray = roi.empty() ? imageGray : imageGray(roi);
  
     float startMS = _timer.elapsedTimeInMilliSec();
  
     arucoIDs.clear();
     objectViewMats.clear();
     CVVVPoint2f corners, rejected;
  
 #if CV_MAJOR_VERSION < 4 || CV_MINOR_VERSION < 7
     cv::aruco::detectMarkers(croppedImageGray,
                              _params.dictionary,
                              corners,
                              arucoIDs,
                              _params.arucoParams,
                              rejected);
 #else
     cv::aruco::ArucoDetector detector(_params.dictionary,
                                       _params.arucoParams);
     detector.detectMarkers(croppedImageGray,
                            corners,
                            arucoIDs,
                            rejected);
 #endif
  
     for (auto& corner : corners)
     {
         for (auto& j : corner)
         {
             j.x += (float)roi.x;
             j.y += (float)roi.y;
         }
     }
  
     CVTracked::detectTimesMS.set(_timer.elapsedTimeInMilliSec() - startMS);
  
     if (!arucoIDs.empty())
     {
         if (_drawDetection)
             cv::aruco::drawDetectedMarkers(imageBgr,
                                            corners,
                                            arucoIDs,
                                            cv::Scalar(0, 0, 255));
  
         /////////////////////
         // Pose Estimation //
         /////////////////////
  
         startMS = _timer.elapsedTimeInMilliSec();
  
         // find the camera extrinsic parameters (rVec & tVec)
         CVVPoint3d rVecs, tVecs;
         cv::aruco::estimatePoseSingleMarkers(corners,
                                              _params.edgeLength,
                                              calib->cameraMat(),
                                              calib->distortion(),
                                              rVecs,
                                              tVecs);
  
         CVTracked::poseTimesMS.set(_timer.elapsedTimeInMilliSec() - startMS);
  
         // Get the object view matrix for all aruco markers
         for (size_t i = 0; i < arucoIDs.size(); ++i)
         {
             CVMatx44f ovm = createGLMatrix(cv::Mat(tVecs[i]), cv::Mat(rVecs[i]));
             objectViewMats.push_back(ovm);
  
             if (_drawDetection)
             {
 #if CV_MAJOR_VERSION < 4 || CV_MINOR_VERSION < 6
 #else
                 cv::drawFrameAxes(imageBgr,
                                   calib->cameraMat(),
                                   calib->distortion(),
                                   cv::Mat(rVecs[i]),
                                   cv::Mat(tVecs[i]),
                                   0.01f);
 #endif
             }
         }
     }
  
     return true;
 }

Member Data Documentation

◆ _arucoID

int CVTrackedAruco::_arucoID

private

Aruco Marker ID for this node.

Definition at line 169 of file CVTrackedAruco.h.

◆ _calibIniPath

string CVTrackedAruco::_calibIniPath

private

Definition at line 170 of file CVTrackedAruco.h.

◆ _params

CVArucoParams CVTrackedAruco::_params

private

Aruco parameters.

Definition at line 168 of file CVTrackedAruco.h.

◆ arucoIDs

vector<int> CVTrackedAruco::arucoIDs

protected

detected Aruco marker IDs

Definition at line 164 of file CVTrackedAruco.h.

◆ objectViewMats

CVVMatx44f CVTrackedAruco::objectViewMats

protected

object view matrices for all found markers

Definition at line 165 of file CVTrackedAruco.h.

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

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ CVTrackedAruco()

Member Function Documentation

◆ drawArucoMarker()

◆ drawArucoMarkerBoard()

◆ params()

◆ track()

◆ trackAll()

Member Data Documentation

◆ _arucoID

◆ _calibIniPath

◆ _params

◆ arucoIDs

◆ objectViewMats